final report, bsee contract number: e13pc00014
TRANSCRIPT
Physical Oceanographic and Meteorological Data for the Beaufort and Chukchi Seas to
Support Reliability-Based Design Criteria for Arctic Offshore Oil and Gas Structures
BSEE contract number E13PC00014
Presented by University of Alaska Fairbanks
Project Team Oceana Francis (UH Manoa) Andrew T Metzger (UAF)
Hank Statscewich (Akka LLC) Peter Winsor (Akka LLC)
February 2016
Abstract
The intent of this project was to produce information that will facilitate implementation of the ISO 19906 Standard Petroleum and Natural Gas Industries - Arctic Offshore Structures (ie the Normative) The information collected in this effort consists of meteorological and oceanographic (metocean) information for US waters in both the Chukchi and Beaufort seas in a format consistent with the philosophy of the Normative Currently implementation of ISO 19906 in US waters is questionable due the lack of meteorological and oceanographic design criteria Appendices B7 (Beaufort Sea) and B8 (Chukchi Sea) of ISO 19906 provide only cursory information that is not necessarily intended for implementation of the Normative ndash ie a reliability-based format A full complement of design values for the regions covered in B7 and B8 is required to implement the normative provisions and ultimately produce safe and reliable offshore structure designs This project included identification of metocean data of good quality and sufficient quantity to serve as an adequate statistical sample of data The data was identified acquired and processed After processing into a common format bulk statistics were calculated from the samples These statics included quantile values corresponding to parameter values with a low rate of occurrence The purpose was to identify those values of metocean parameters that have occurred but occur infrequently This approach was implemented after it was determined that fitting probability density functions to the data was not a reasonable description for metocean phenomenon in the region This is the best compromise that could be achieved while still supporting the ISO 19906 which is reliability (Probability Theory) based in philosophy
Section Page Introduction 3
Section 1 M eteorological Data 4
Meteorological BEAUFORT SEA 6
Meteorological CHUKCHI SEA 18
Section 2 Oceanographic Data 31
Oceanographic BEAUFORT SEA 36
Oceanographic CHUKCHI SEA 41
Section 3 Limitations amp
Recommendations 51
Section 4 Source Data Narrative 55
Section 5 Bibliography 77
Table of Contents
2
Introduction
The intent of this project is to produce information that will facilitate implementation of the ISO 19906 Standard Petroleum and Natural Gas Industries - Arctic Offshore Structures (ie the Normative) The information collected in this effort consists of meteorological and oceanographic (metocean) information for US waters in both the Chukchi and Beaufort seas in a format consistent with the philosophy of the Normative Currently implementation of ISO 19906 in US waters is questionable due the lack of meteorological and oceanographic design criteria Appendices B7 (Beaufort Sea) and B8 (Chukchi Sea) of ISO 19906 are intended to provide this information but numerical values are sparse and the format of the data is not consistent with the philosophy of the Normative ndash ie a reliability-based format A full complement of design values for the regions covered in B7 and B8 is required to implement the normative provisions and ultimately produce safe and reliable offshore structure designs
This project included a literature review The review summarized the general metocean conditions in the region of the study and is divided into two main sections correspond to meteorological and oceanographic condition Each of those sections is divided into discussions of each sea
This project included identification of metocean data of good quality and sufficient quantity to serve as an adequate statistical sample From the sample values that occur infrequently could be identified This was typically achieved by identifying quantile values ndash 95th quantile 99th quantile 9999th quantile etc The number of data points dictated the highest quantile value that could be achieved For example the 9999th quantile requires more than 10000 data points to be meaningful Minimum and maximum values are also cited in the report The samples acquired for this project generally cover multiple years Data collected prior to 1990s [with a few exceptions] was not used The purpose of this was to avoid the impacts of any climatic changes while still maintain a robust statistical sample
Data was identified acquired and processed After processing into a common format bulk statistics were calculated from the samples These statistics included quantile values corresponding to parameters values with a low rate of occurrence The purpose was to identify those values of metocean parameters that have occurred but occur infrequently This approach was implemented after it was determined that fitting probability density functions to the data was not a reasonable description of data in the region This is the best compromise that could be achieved while still supporting the ISO 19906 which is reliability-based (Probability Theory) in philosophy Because reliability theory that is the probability of non-failure (non-exceedance of a limit state) is fundamental to the Normative a reasonable statistical sample of relevant parameters needed to be acquired The statistics of the samples was used to estimate magnitudes of metocean parameters with a low rate of occurrence
It was the intent of this project to produce results that may be readily implemented by the reader Analysis of the implications of the statistical results is not part of this project The data acquired for this study was acquired from publically available sources and was of such integrity as to be trust worthy It is known there is much additional data in the private domain and the results here are not comprehensive However a relatively robust set of measurements was acquired for most of the critical metocean metrics from the perspective of offshore structures
3
Section 1 Meteorological Data
General Regional Meteorological Conditions Surface wind is the dominant load type of all meteorological conditions affecting offshore structures The highest offshore surface winds can be linked to synoptic and mesoscale weather systems In the BeaufortndashChukchi Seas (BCS) most storm systems do not form locally but move into the region when upper-level winds are favorable and the storm end point depends on the large scale pressure systems acting on it (Francis and Atkinson 2012)
In the BCS region two storm paths are generally found (Francis and Atkinson 2012) The first path includes North Pacific systems which move into the Bering Sea and transit the Bering Strait and then move up into the Chukchi Sea A secondary storm path runs roughly east to west across the north Alaskan coast These large weather systems (1000s of km in extent) in general depend on baroclinic atmospheric conditions which explain their greater frequency in the non-summer period (Mesquita et al 2010) The most powerful systems which can attain central mean sea level pressures (MSLPs) down into the 930 hPa range with winds of +50 ms form under less-common conditions when large quantities of water vapor are available in the mid-troposphere and dynamical support is available in the form of a suitably situated upper-air trough (Francis and Atkinson 2012)
Synoptic scale pattern Synoptic scale patterns (horizontal dimensions 1000 km+) affecting the BCS are characterized by the Beaufort High (BH) and the Aleutian Low (AL) The BH represents anticyclonic high pressure weather patterns that rotate in a clockwise direction The AL represents the impact of cyclonic low pressure systems that rotate in a counter clockwise direction In a cyclone air moves upwards in the center of the pattern bringing stormy wet weather (NSIDC 2016) Traveling cyclones formed in subpolar latitudes in the North Pacific usually slow down and reach maximum intensity in the area of the Aleutian Low Therefore the AL is dominant in southern Alaska and high pressure BH is prevalent over the BCS High winds are associated with a strong pressure gradient between the AL and the BCS and also with a low pressure system to the north of Barrow (Cassano et al 2006) High (low) air temperature extremes are associated with patterns that produce strong southerly (northerly) air flow (Cassano et al 2006)
The largest driver of surface winds is due to BCS cyclone activity generated from the AL There has also been an increase in cyclonic activity thus creating greater surface winds speeds From 1948ndash2002 there has been an increase in Arctic cyclone activity (Zhang et al 2004) Zhang et al (2004) found that the number and intensity of cyclones entering the Arctic from the mid-latitudes has increased particularly in summer Also the positive tendencies of mid-latitude cyclone activity correlate with variations of cyclone activity in the North Atlantic and Eurasian sectors Synchronized phase and amplitude variations play a critical role in determining the variations of cyclone activity During 1948-2002 the Arctic cyclone activity displayed significant low-frequency variability and corresponded to the alternation of the cyclonic and anticyclonic regimes of sea ice and the ocean
The cyclones of October 1963 and August 2000 produced the highest winds (25 ms gusts 33 ms) ever recorded in Barrow Alaska which displayed unusual behavior as they tracked eastward from the East Siberian Sea into the Chukchi and Beaufort Seas rather than following a more
4
typical northward track into the Arctic Ocean (Lynch et al (2003) Lynch et al (2003) believed that ice retreat north of Eurasia may have an impact on the increasing cyclonic activity in BCS region
Anticyclonic activity becomes notable during the strengthening of the BH which is generally in summer and autumn For the period of 1979ndash2012 in the BCS region Wu et al (2014) found significant anticyclonic trend among surface wind fields associated with a strengthened BH during summer and autumn but significant cyclonic trends associated with a weakened BH during early midwinter consistent with significant trends in sea level pressure (SLP) gradients between western Arctic Ocean and the adjoining landmass
Surface winds Stegall and Zhang (2012) observed the wind field climatology changes and extremes from 1979 to 2009 for the BCS regionAlaska North Slope Monthly averaged and 95th percentile wind speeds show a seasonal cycle with a minimum of 2ndash4 ms in May and a maximum up to 9 ms (15 ms in October for 95th percentile) and the prevailing wind direction is northeast at a frequency of 40ndash60 for most of the year The wind speeds showed a clear diurnal cycle over land and sea ice areas during the warm seasons There has also been an increasing trend in averaged monthly mean and 95th percentile wind speeds for July through November particularly in October from 7 ms in 1979 to 105 ms in 2009 The frequency of extreme wind events (above the 95th percentile winds) shows an increasing trend in all months greatest increase in October with 8 more extreme wind events in 2009 compared to 1979
During 1979 to 2009 the climatology also illustrated strong distinctions between coastal and interior locations strong seasonal characteristics and diurnal cycles in wind speed (Baule and Shulski 2014) (Baule and Shulski 2014) found negative trends in wind speed particularly in Alaska Also trends in reanalysis data opposed in situ trends at most locations justifying the need for further in situ studies
Wind speeds in the BCS region over the period 1970ndash2013 show significant increases over the Bering Sea to the north of Alaska in July and over the central part of BCS in August and September with decreases in the region off the Canadian coasts in August (Wang et al 2015) In the region west of the Canadian coast the climatological mean wind direction has rotated clockwise in July and August with the climatological anticyclonic center being displaced northeastward in August
Other factors influencing surface winds and atmospheric circulation The geography plays an important role in the Beaufort-Chukchi Seas (BCS) The geography in the region is characterized by a seasonally ice-covered ocean along with high mountains inland eg Brooks Range in northern Alaska There is also temperature considerations especially in the winter where there is little-to-no sunlight during the winter months which can cause the surface to become extremely cold and often results in temperature inversions The geographic features and temperature influence the weather systems that are generated yielding a complex mesoscale circulation which influences the surface winds in the region
5
Cloud cover also influences atmospheric circulation There have been have been changes in the atmospheric circulation thus changes in cloud cover which has a major impact to the surface energy balance (Schweiger 2004) In ocean areas north of 60degN a 5decade decrease in cloud cover during winter (December January February) and up to a 15decade increase in spring (March April May) in cloud cover especially in the Central Arctic was found (Schweiger 2004)
Mesoscale patterns Less common to the BCS region are the mesoscale patterns (horizontal dimensions 5 km to several 100s of km) which are characterized by polar lows (PL) PLs are small intense cyclones that are short-lived which form over the open ocean during cold seasons PLs form when cold Arctic air flows over relatively warm open water A PL ranges in size from around 100 to 500 km in diameter The storms can develop and dissipate rapidly reaching their maximum strength within 12 to 24 hours of formation lasting on average 1-2 days (CPC 2016) Wind speeds average around 22 ms although they can occasionally reach hurricane strength of 29 ms (CPC 2016) However examples of extreme cases of polar lows in the BCS region include an event that occurred on 14-15 September 1970 and another event that occurred on 27 July 1982 (Rasmussen and Turner 2003) The event that occurred on 14-15 September 1970 included three separate hurricanes that formed in the southern Beaufort Sea One of the 1970 hurricanes had winds of +50 ms The 1970 event also generated a storm tide that caused loss of life and property damage Another example of a PL event occurred in 1982 which produced strong winds of up to 30 ms over a drilling area in the Beaufort Sea It had initially developed as a trough which intensified dramatically in the MacKenzie Bay
Moirera (2011) studied a polar low in the BCS region which had a hybrid development and that surface forcings were not important for its formation and intensification The polar low was believed to have been triggered by the interaction of an upper-level potential vorticity anomaly over a low-level baroclinic zone which was favored by the synoptic environment in which the polar low formed Thus there may be other polar lows formed in such a manner
Meteorological BEAUFORT SEA
The meteorological data utilized in this study were taken from (NDBC 2014) and (Zhang et al 2013 2016) These stations include offshore data from buoys ships and exploration well sites Observed variables include surface air temperature (degC) dew point temperature (degC) relative humidity () wind speed (m s-1 ) wind direction (degrees) station pressure (hPa) sea level pressure (hPa) altimeter (in Hg) shortwave radiation (W m-2 ) longwave radiation (W m-2 ) 1-hr accumulated precipitation (mm) 6-hr precipitation (mm) 24-hr precipitation (mm) and snow depth (cm) ]
6
Figure 11 location of Beaufort Sea meteorological buoys
Figure 11 shows the locations at which the data was collected
Air Temperature Air temperature data from the following sources was plotted checked for integrity and collated
buoyPRDA20 4 samples buoyPRDA21 5 samples
Cabot 1 sample Cottle Island 4 samples
Drew Point 13 samples Endicott 6 samples
McCovey 1 sample Northstar 6 samples
Phoenix 1 sample Prudhoe Bay 3 samples
Pt McIntyre Pad 1 sample Reindeer Is 1 sample
Each lsquosamplersquo corresponds to measurements collected over a calendar year Years that data was collected ranged from 1999 to 2014 The data was separated by month and histograms were plotted From inspection of the monthly histograms no apparent uniformity or trend was revealed See Figure 12
While it is possible to fit the data to a probability density function for the purposes of extrapolating extreme values the results would be questionable due to the irregularity of the histogram Such irregularity indicates is does not conform to a standard pdf However the variability in temperature for each month may be assessed qualitatively from Figure 12
7
Figure 12 Monthly histograms of air temperature data
Because of the difficulty in formulating a probability-based approach with these results bulk statistics for the air temperature data have been provided Table 11 summarized the data by month Temperature extremes are characterized with quantile values as well as the maximum and minimum observed As an example for March statistically speaking only 1 of the observed values are colder than -397degC Correspondingly 99 of the temperatures are warmer than -397degC Figure 13 is a plot of the results from Table 11
Average monthly freezing thawing degree days were estimated using mean monthly air temperature values and the number of days in each month The results are shown in Figure 14
8
No Month Data Pts Min 1st th Mean Median 95th 99th Max
1
2
January
February
103339
94006
-477
-479
-422 5 -416
-385
-38
-26
-247
-259
-254
-142
-101
-42
-46
3
33
3 March 90604 -451 -397 -367 -264 -265 -153 -111 -35
4 April 75545 -377 -296 -258 -149 -149 -42 08 81
5 May 84891 -285 -185 -143 -53 -47 2 39 12
6 June 83153 -74 -34 -18 17 14 66 117 20
7 July 89579 -3 -04 1 56 52 121 156 233
8 August 129157 -3 -04 09 51 46 117 154 252
9 September 153307 -116 -36 -21 19 15 69 103 175
10 October 114205 -259 -171 -121 -46 -38 03 32 113
11 November 101957 -388 -35 -295 -159 -154 -57 -31 28
12 December 112462 -41 -379 -341 -204 -196 -76 -35 3
Table 11 Beaufort Sea monthly air temperature results temperatures are in degC
9
Figure 13 Beaufort Sea bulk statistics for air temperature data
10
Figure 14 Beaufort estimated monthly mean freezing thawing degree days
Wind Speed Wind speed data from the following sources was plotted check for viability in this study collated and separate by month
buoyPRDA20 4 samples buoyPRDA21 5 samples
Cabot 1 sample Cottle Island 4 samples
Drew Point 13 samples Endicott 6 samples
McCovey 1 sample Northstar 6 samples
Phoenix 1 sample Prudhoe Bay 3 samples
Each lsquosamplersquo corresponds to measurements collected over one or more calendar years Years that data was collected ranged from 1999 to 2014 The data was separated by month and histograms were plotted See Figure 15 From the histograms it can be seen that a one-sided pdf may be appropriate for the data However some months appear to be more consistent than others from this perspective
For each month mean and quantile statistics were calculated and are shown in Table 12 Figure 16 is a plot of the Table 12 data
11
Figure 15 Monthly histograms of wind speed for Beaufort Sea collection sites
A histogram for the combined data is shown in Figure 17 Based on the corresponding probability plot the associated distribution may be a reasonable approximation of the uncertainty in wind speed Of the pdfs applied to the combined data the Max-Stable Distribution of the following form appeared to fit the data well
1 1 x 1 x
1 e
Where = location parameter 468454
= scale parameter 312926
= shape parameter 00567011
12
Figure 16 Plot of Beaufort monthly wind speed statistics
The Max-Stable Distribution represents a generalized extreme value distribution
Table 12 Beaufort monthly wind speed statistics values in ms
No Month Data Pts Mean Median 95th 99th 9999th Max
1 January 94125 66 57 16 204 267 281
2 February 89927 69 62 152 184 265 28
3 March 93993 65 58 139 175 226 241
4 April 97103 64 59 13 171 225 254
5 May 96962 63 55 144 176 218 234
6 June 94300 68 62 142 181 242 259
7 July 91851 66 62 123 151 19 218
8 August 125908 6 54 125 166 236 274
9 September 153434 72 63 155 192 274 275
10 October 118275 78 68 183 237 318 325
11 November 107413 67 55 168 204 276 288
12 December 99358 62 51 155 197 313 329
Mathematically extreme value distributions are the limiting distributions for the minimum or maximum of a very large collection of random observations from the same [arbitrary]
13
Figure 17 Combined Beaufort wind speed data fit to Max-Stable Distribution
distribution The values for the distribution parameters shown above were calculated with the combined wind speed data
A summary of bulk statistics for the combined data is shown in Table XX The table compares the statistical quantile values and those determined with the theoretical pdf fitted to the data
Table 13 is a summary of bulk statistics for combined wind speed data and values corresponding to Max-Stable Distribution lsquopdf valuesrsquo correspond to Max-Stable Distribution with parameters shown with equation values in ms
Table 13 Summary of bulk statistics for combine wind speed data and theoretical pdf
Combined Data Pts Mean Median 95th 99th 999th 9999th Max Data 1262649 67 59 149 193 251 294 329
pdf 148 211 311 425 Wind Direction The wind data used in the previous section also included wind direction data The direction data represents the direction the wind is coming from in degrees clockwise from True North Figure 18 shows the wind directionality for the entire wind data set East-west wind are dominant with easterly winds being more frequent on an annual basis
Figure 19 is the wind direction frequency by month From the figure it is apparent the wind exhibits east-west directionality However easterly winds are predominate in the summer months
14
Figure 18 Wind rose for combined Beaufort data
Wind Speed vs Wind Direction Wind speed and direction measurement allow examination of the relationship between the two Figure 110 is a plot of the frequency of wind magnitude and direction
The graphic confirms that the strongest and most frequent winds are from the east Westerly winds are the next most predominant direction Table 14 and Figure 111 further summarize the results and provide quantile values from the data for wind speed versus direction
15
Figure 19 Beaufort wind direction frequency by month
16
Beaufort Wind Speed vs Direction
002frequency
360 330
001 300 270 240
000 210 0
4 8
12 120 150 180
di recti on deg
16 90
m s 20 24
28 30
60
32 0
Figure 110 Beaufort wind speed vs direction
Precipitation amp Visibility
The samples used for the Beaufort meteorological portion of the prject did contain fields for precipitation However most the entries were ldquoNullrdquo or the numbers did not appear to be meaningful No precipitation results were acquired in this effort
The data search effort was not able to identify any relevant data regarding visibility
17
ms
Beaufort Sea Wind Speed vs Direction34 34
agrave agrave aelig
agrave aelig
agrave agrave aelig aelig
agrave aelig
aelig agrave
aelig agrave
Max agrave aelig aelig
agrave
aelig999 th 9 aelig aelig Max
aelig aelig aelig agrave
aelig agrave aelig9999 th
aelig aelig
aelig aelig aelig aelig99th
99th aelig aelig
aelig aelig aelig
95 th aelig aelig aelig aelig aelig aelig95th
aelig aelig
aelig aelig aelig
aelig
aelig aelig aelig
aeligMean aeligMean aelig aelig aelig
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
32
30
28
26
24
22
20
18
ms
16
14
12
10
8
6
4
2 2
0deg 30deg 60deg 90deg 120 deg 150 deg 180 deg 210 deg 240 deg 270 deg 300 deg 330 deg
Table 14 Beaufort Wind Speed vs Direction values in ms
Direction Mean 95th 99th 9999th Max 0 34 76 113 185 206 30 39 84 109 225 237 60 65 129 165 269 288 90 9 175 207 297 325 120 8 17 219 313 329 150 34 67 84 143 175 180 33 71 95 19 256 210 42 91 119 19 211 240 53 113 154 224 238 270 63 124 163 243 28 300 51 11 143 274 284 330 42 87 127 162 176
wind direction
Figure 111 Summary of Beaufort wind speed vs direction values
Meteorological CHUKCHI SEA
Like the Beaufort meteorological section the meteorological data utilized in this portion of the project were taken from (NDBC 2014) and (Zhang et al 2013 2016) These stations include offshore data from buoys ships and exploration well sites Observed variables include surface air temperature (degC) dew point temperature (degC) relative humidity () wind speed (m s-1 ) wind direction (degrees) station pressure (hPa) sea level pressure (hPa) altimeter (in Hg) shortwave radiation (W m-2 ) longwave radiation (W m-2 ) 1-hr accumulated precipitation
18
Figure 112 Location of Chukchi data collection
(mm) 6-hr precipitation (mm) 24-hr precipitation (mm) and snow depth (cm) ] Figure 112 shown the location at which the Chukchi data was collected
Air Temperature Air temperature data from the following sources was plotted checked for integrity and collated
Barrow 14 samples Point Lay 16 samples
Popcorn 1 sample Shell Buoy 2 samples
Wainright 1 sample
Each lsquosamplersquo corresponds to measurements collected over a calendar year Years that data was collected ranged from 1991 to 2013 The data was separated by month and histograms were plotted From inspection of the monthly histograms no apparent uniformity or trend was revealed See Figure 113
While it is possible to fit the data to a probability density function for the purposes of extrapolating extreme values the results would be questionable due to the irregularity of the histogram Such irregularity indicates is does not conform to a standard pdf However the variability in temperature for each month may be assessed qualitatively from Figure 113
Because of the difficulty in formulating a probability-based approach with these results bulk statistics for the air temperature data has been provided Table 15 summarized the data by month Temperature extremes are characterized with quantile values as well as the maximum and
19
temperature values and the number of days in each month The results are shown in Figure 115
Figure 113 Chukchi monthly temperature histograms
minimum observed As an example for October statistically speaking only one percent of the observed values are colder than -294degC Correspondingly 99 of the temperatures are warmer than -294degC Figure 114 is a plot of the results from Table 15
Average monthly freezingthawing degree days were estimated using mean monthly air
20
Table 15 Chukchi Sea monthly air temperature results temperatures are in degC
Data No Month Pts Min 1st 5th Mean Median 95th 99th Max
1 January 19520 -428 -406 -367 -251 -256 -138 -57 11
2 February 16659 -483 -413 -372 -251 -26 -99 -22 28
3 March 18321 -428 -372 -339 -241 -25 -10 -39 11
4 April 19020 -356 -294 -256 -148 -151 -31 11 39
5 May 19516 -265 -183 -146 -53 -44 22 61 156
6 June 17714 -72 -39 -22 29 22 106 139 222
7 July 17035 -72 -39 -22 46 33 139 183 261
8 August 19392 -39 -16 -01 57 5 133 172 228
9 September 19717 -138 -5 -28 18 12 78 10 172
10 October 20692 -294 -20 -161 -56 -4 1 26 72
11 November 20470 -372 -317 -256 -145 -15 -33 -06 5
12 December 19133 -41 -357 -322 -201 -206 -61 -22 39
21
Figure 114 Chukchi Sea bulk statistics for air temperature data
22
Figure 115 Chukchi estimated monthly mean freezing thawing degree days
Wind Speed Wind speed data from t he following sources was plotted check for viability in this study collated and separate by month
Barrow 14 samples Point Lay 16 samples
Conoco Ship 1 sample Crackerjack 1 samples
Shell Buoy 2 sample buoy48012 1 sample
buoy48213 1 sample buoy4814 1 sample
Diamond 1 sample buoy8211 2 samples
Popcorn 1 sample Wainright 1 sample
Each lsquosamplersquo corresponds to measurements collected over one or more calendar years Years that data was collected ranged from 1989 to 2013 The data was separated by month and histograms were plotted See Figure 116 From the histograms it can be seen that a one-sided pdf may be appropriate for the data However some months appear to be more consistent than others from this perspective
For each month mean and quantile statistics were calculated and are shown in Table 16 Figure 117 is a plot of the Table 16 data
Analysis of the combined data did not reveal a pdf that might serve as a reasonable for the combine Chukchi wind speed data The histogram for the combined data is shown in Figure 118 Bulk statistics for the combined wind speed data are shown in Table 17
23
Figure 116 Chukchi monthly wind speed histograms
24
Figure 117 Plot of Chukchi monthly wind speed statistics
Table 16 Chukchi monthly wind speed statistics values in ms
No Month Data Pts Mean Median 95th 99th 9999th Max
1 January 18545 59 49 134 17 237 237
2 February 17448 65 58 134 165 241 241
3 March 18694 59 49 134 17 206 215
4 April 19027 54 48 107 139 20 201
5 May 19281 55 49 107 139 197 206
6 June 18182 54 49 10 123 228 255
7 July 25345 62 58 126 161 208 247
8 August 32062 54 49 103 128 231 277
9 September 79868 57 52 112 141 216 226
10 October 49041 63 59 122 149 221 255
11 November 18254 59 51 124 148 197 20
12 December 17776 58 49 125 156 215 228
25
Figure 118 Histogram for combined Chukchi wind speed data
Table 17 Bulk statistics for combined Chukchi wind speed data
Combined Data Pts Mean Median 95th 99th
Data 333523 58 52 116 149
999th
189
9999th
219
Max
277
26
Figure 119 Wind rose for combined Chukchi data
Wind Direction The wind data used in the previous section also included wind direction data The direction data represents the direction the wind is coming from in degrees clockwise from True North Figure 119 shows the wind directionality for the entire wind data set East-Northeast amp West-Southwest appear to be the dominant wind direction with the former being most dominant
Figure 120 is the wind direction frequency by month From the figure it is apparent the wind exhibits east-west directionality However easterly winds are predominate in the summer months
27
Figure 120 Chukchi wind direction frequency by month
28
Wind Speed vs Wind Direction Figure 121 is a representation of the combined wind speed versus direction The graphic confirms that the strongest and most frequent winds are East-Northeast and West-Southwest Table 8 and Figure 122 further summarize the results and provide quantile values from the data for wind speed versus direction
Chukchi Wind Speed vs Direction
0020
0015frequency
360
0010 300 330
0005 270 240
0000 210 0
4 150 180
di rection deg
8 120 12 90
m s 16 60 20
30 24
28 0
Figure 121 Chukchi wind speed vs direction
Precipitation amp Visibility
The samples used for the Chukchi meteorological portion of the project did contain fields for precipitation However most the entries were ldquoNullrdquo or the numbers did not appear to be meaningful No precipitation results were acquired in this effort
The data search effort was not able to identify any relevant data regarding visibility
29
Figure 122 Summary of Chukchi wind speed vs direction values
Table 18 Chukchi Wind Speed vs Direction values in ms
Direction Mean 95th 99th 9999th Max
0 52 105 13 226 232
30 6 116 142 206 255
60 7 134 165 215 241
90 59 116 148 237 241
120 51 108 139 176 178
150 45 96 123 206 255
180 44 98 143 197 247
210 52 116 161 215 228
240 61 114 142 202 209
270 64 12 15 222 231
300 54 107 14 216 221
330 54 113 158 207 277
30
Section 2 Oceanographic Data
General Regional Oceanographic Conditions The Chukchi and Beaufort Seas are atmospherically and oceanographically linked to the Pacific Ocean This basin-scale connection strongly influences the wind regime the seasonal distribution of sea ice the regional hydrologic cycle and the water masses and circulation of the Chukchi shelf The atmospheric connection is primarily via the Aleutian Low whose time-varying position strength and interactions with the anticyclonic Beaufort High (Zhang et al 2013) affect regional meteorological conditions The mean northward ocean flow through Bering Strait connects the Bering Sea shelf and basin with the Chukchi Sea and is sustained by a large-scale pressure gradient between the Pacific and Atlantic oceans (Coachman et al 1975 Aagaard et al 2006 Figure X [a map of the study area]) that opposes the prevailing northeasterly winds The circulation and water properties of the Chukchi Sea shelf are profoundly influenced by the northward flow from Bering Strait The physical characteristics of the Chukchi shelf are established by the highly variable northward flux of mass heat and salt through the Bering Strait There is presently no reliable means for predicting these fluxes which are due to a variety of complex processes occurring south of the Strait (Weingartner et al 2005 Aagaard et al 2006 Danielson et al 2006) all of which set the heat and salt budgets of the Chukchi Sea shelf (Coachman et al 1975 Woodgate et al 2005)
Bering Strait inflow ~800000 m3 s-1 on average varies seasonally from a maximum in summer to a minimum in winter The accompanying freshwater and heat fluxes vary seasonally (again being a maximum in summer) and average ~2500 km3 yr-1 and 2-3 x 1020 J respectively (Woodgate et al 2006 Woodgate et al 2012) The bulk of the Bering Strait heat flux occurs between May and September and it takes ~3-6 months for waters entering Bering Strait in mid-summer to reach the northern portions of the Chukchi shelf (Winsor and Chapman 2004 Weingartner et al 2005) The heat flux exerts a critical control on the seasonal retreat and formation of sea ice on the shelf Ice begins retreating northward from Bering Strait in early May about one to two months before ice begins retreating over the adjacent shelf seas The northward heat transport is not uniformly distributed across the Chukchi Sea shelf but is steered by the shelf topography along three pathways Herald Valley in the west the Central Channel midshelf and Barrow Canyon in the northeast These pathways lead to differential oceanic heat flux convergences that result in spatially varying patterns of ice retreat which were known to 19th century whaling crews (Bockstoce 1986) Because of the northward heat flux through Bering Strait the spring retreat of sea ice occurs earlier and the fall onset occurs later compared to most other Arctic shelves Woodgate et al (2006) estimate that summer Pacific waters provide a heat source capable of melting nearly the entire (~640000 km2) two meter thick ice cover of the Chukchi Sea and Shimada et al (2006) contend that this flux may be an important source of interannual variability in the ice cover of the western Arctic Ocean The heat flux through Bering Strait maintains subsurface temperatures well above the freezing point in much of the Chukchi Sea through November and possibly longer (Weingartner et al 2005 Weingartner et al 2013) This results in ice formation occurring in late October and November even though vigorous atmospheric cooling begins in late September ndash early October (Weingartner et al 2013) Consequently broad expanses of the Chukchi Sea remain ice-free through autumn even though extensive ice covers have formed on the East Siberian and Alaska Beaufort shelves by this time
31
Mean Circulation and Water Masses The ocean circulation flows over the shallow (~50m) Chukchi Sea shelf which extends ~800 km northward from Bering Strait to the shelfbreak at about the 200 m isobath A western branch flows northwestward from the strait and exits the shelf through Herald Canyon While most of this outflow probably descends through Herald Canyon some of it may spread eastward across the central shelf A second branch flows northward through the Central Channel and then splits some water continues eastward toward the Alaska coast along the south flank of Hanna Shoal (Weingartner et al 2005 Weingartner et al 2013) while the remainder flows northeastward toward the continental slope The third branch flows northeastward along the Alaska coast to Barrow Canyon at the junction of the Chukchi and Beaufort shelves In summer this flow includes the northward extension of the Alaskan Coastal Current (ACC) that originates south of Bering Strait At the head of Barrow Canyon the ACC is joined by waters flowing eastward from the central shelf with the merged flow then continuing down canyon as a narrow but strong coastal jet (Pickart et al 2005) From summer through early fall Bering Strait transport is northward on average and includes three major water masses Following the nomenclature of Coachman et al (1975) and Walsh et al (1989) they are cold salty Anadyr Water warm fresh Alaskan Coastal Water (ACW) and Bering Shelf Water The latter has properties intermediate between but nonetheless distinct from the Anadyr and Alaskan Coastal water masses Coachman et al (1975) maintain that the Anadyr and Bering Shelf water masses mix to form Bering Sea Water (BSW) north of the Strait whereas ACW maintains its properties on the Chukchi shelf In summer and fall Chukchi bottom waters often include dense near-freezing saline waters that formed in winter by freezing over both the Bering and Chukchi seas In addition shallow (surface) plumes of cool dilute surface waters formed by ice melt may also be present BSW is transported to the northwest Chukchi over the central shelf and northward through the Central Channel (Weingartner et al 2005 Woodgate et al 2005) Weingartner et al (2005) and Weingartner et al (2013) suggest that south of Hanna Shoal some central-shelf waters flow eastward toward the coast in agreement with circulation models (eg Winsor and Chapman 2004 Spall 2007) North of the Central Channel both models of Winsor and Chapman (2004) and Spall (2007) suggest the average flow follows the bathymetry around the western and northern flanks of Hanna Shoal before turning southward along the eastern side of the Shoal and then eventually entering Barrow Canyon
In summer and fall Chukchi bottom waters often include near-freezing saline (dense) waters that formed in the previous winter during freezing over both the Bering and Chukchi seas In addition shallow plumes of cool dilute surface waters formed by ice melt may also be present BSW is transported to the northwest Chukchi over the central shelf and northward through the Central Channel (Weingartner et al 2005 Woodgate et al 2005a 2005b) Weingartner et al (2005) suggested that south of Hanna Shoal some central-shelf waters flow eastward toward the coast in agreement with the circulation models of Winsor and Chapman (2004) and Spall (2007) North of the Central Channel where there are no long-term current measurements both models suggest the average flow follows the bathymetry around the western and northern flanks of Hanna Shoal From here the flow moves southward along the eastern side of the Shoal (presumably between the 40 m and 60 m isobaths) before eventually entering Barrow Canyon However the models also predict that some of the water along the east side of Hanna Shoal penetrates southwestward along the southern edge of the Shoal before turning eastward towards the coast The ACW flows northeastward within the Alaskan coastal current toward the head of Barrow Canyon Here it merges with waters flowing eastward from the central shelf to form the
32
canyon outflow Hence in summer and fall the canyon outflow contains a horizontally- and vertically-structured complex of water masses (Pickart et al 2005 Shroyer and Plueddemann 2012) that include ACW meltwater dense winter waters BSW and mixtures of each
To a large extent the Chukchi circulation appears consistent with barotropic geostrophic dynamics in which the shelf pressure field arises as a response to wind-forced convergences and divergences and to the mean pressure difference between the Pacific and Arctic oceans The latter provides the impetus for the northward transport through Bering Strait Even though much of the Chukchi shelf has a gently varying bathymetry topographic control appears to exert an important influence on the shelf dynamics Thus north of the Strait the model streamlines parallel contours of f h (where f is the Coriolis parameter and h is the water depth) Over the northeastern shelf mean winds are from the east-northeast so that in the mean the flow opposes the winds Nevertheless flow variations are primarily wind-forced and occasionally the wind stress can be sufficiently strong to reverse the flow (Weingartner et al 1998 2005)
Recently collected year-long current meter data (Weingartner unpublished data) from the 50 m isobath on the northwest and northeast sides of Hanna Shoal allow some preliminary comparisons with this aspect of the model-predicted circulation In accordance with the models the flow on the northwest side of Hanna Shoal is eastward on average and in fact remarkably steady in spite of substantial variability in the wind field In contrast to the model which suggests southerly mean flow on the northeast side of the Shoal the observations indicate that the flow is zero in the mean and far more variable than the flow northwest of the Shoal However the models also predict that some of the water along the eastern flank of Hanna Shoal penetrates southwestward along the southern flank of the Shoal before turning eastward towards the coast Hydrography suggests that this indeed does occur at least episodically (Weingartner et al 2013) The ACW flows northeastward within the Alaskan Coastal Current toward the head of Barrow Canyon where it merges with waters flowing eastward from the central shelf to form the canyon outflow Hence in summer and fall the canyon outflow contains a horizontally- and vertically-structured complex of water masses (Pickart et al 2005 Shroyer and Plueddemann 2011) that include ACW meltwater dense winter waters BSW and mixtures of each
Wind-Forced Variability The mean ocean circulation due to the large-scale pressure head difference between the Pacific and Arctic Oceans opposes the mean winds which are from the northeast at ~4 m s-1 Wind forcing the principal cause of the substantial flow variations varies seasonally with the largest variations being in fall and early winter and the smallest being in summer Weingartner et al (2005) found that current fluctuations were coherent with wind velocity variations over the northeast shelf over spatial scales of at least 300 km and reflect wind-induced coastal convergences and divergences to the shelf pressure field Both the wind-forced and mean currents are more vigorous in regions of steep topography (Central Channel and Barrow Canyon) than in areas of gentler bottom relief On occasion and most frequently in fall and winter strong northeasterly storm winds can reverse the shelf flow field or even re-distribute the flow from one of the main flow pathways to another That the time-varying shelf pressure field may result in forces that oppose the surface wind stress has important implications for the work proposed here In particular it suggests that the flow in a ldquothinrdquo surface layer which absorbs the bulk of the momentum imparted by the wind to the water column may differ from deeper currents driven by
33
pressure gradients The thickness of this wind-shear layer will vary due to wind velocity bathymetry and the stratification Understanding the surface circulation is critical for assessing potential pathways of drifting ice and ocean heat fluxes but also challenging because moored current meters have difficulty measuring the uppermost ~5 m
In summary the modeled and observed mean circulation are in broad agreement with one another In the northeast Chukchi Sea the area of greatest variability (and possibly the greatest uncertainty) is in the region south and east of Hanna Shoal These regions are likely to be among the first areas where ice forms in fall on the shelf Aspects of this variability are described next The Chukchi Sea Environmental Studies Program has collected hydrographic data in this region between August and early October annually since 2008 These and other hydrographic data collected under BOEM sponsored programs indicate that in general a front extending across Statoil and Burger and the region to the east of Burger separating unstratified or weakly stratified waters south of the front from stratified waters to the north This front and year-to-year water property variations are illustrated by a comparison of two vertical sections taken in 2011 and 2012 that extend northeastward from Klondike diagonally across Burger and along the eastern flank of Hanna Shoal Fronts in the Chukchi Sea are numerous and can occur over a large range of spatial scales as narrow as ~ 1 km across (Timmermanns and Winsor 2012)
Temperature and salinity distributions In this section we describe briefly the spatial seasonal and interannual variations in temperature and salinity of the northeastern Chukchi Sea area We first consider the temperature and salinity sections as shown in Gall et al (2015) The section nomenclature follows Table 1 of Weingartner et al (2015) AS09 implies that the data along this transect were collected on the AugustndashSeptember cruise in 2009
In 2008 the JA08 sections show that waters within 10ndash20 m of the bottom consisted of cold (leminus1 degC) and salty (ge325) dense waters formed over the previous winter Warmer (ge0 degC) and fresher (le31) waters enveloped the upper half of the water column of Burger Over the remainder of Klondike lease area the upper layer waters were warmer (2ndash4 degC) and moderately saline (315ltSlt325) Klondike waters warmed and freshened throughout 2008 Below ~20 m these changes reflect the replacement of winter waters by BSW
Within the upper layer of Klondike some dilution occurred due to infiltration of low-salinity (le31) waters most likely meltwater filaments that were advected into the area and warmed by solar heating Within Burger the bottom waters remained cold and salty and meltwaters occupied the upper 15 m throughout 2008
Conditions in 2009 were very different from those in 2008 in several ways During A09 the uppermost 15 m included shallow low-salinity (lt30) plumes with temperatures generally gt5 degC Below the plumes and to 25 m depth (and elsewhere at the surface) warmer (5ndash6 degC) and saltier (31ndash315) waters were present Bottom water temperatures and salinities were also substantially warmer and less saline in 2009 temperatures ranged from minus1 to 2 degC and salinities varied from 32 to 325 with the densest bottom waters in the northeastern half of Burger By the S09 survey the low-salinity surface plumes were absent from Klondike and the upper 30 m had nearly vertically-uniform temperatures (5ndash6 degC) and salinities (31ndash315) Bottom waters had warmed also and were generally lt2 degC However Burger bottom waters still consisted of cold salty
34
winter water By the time of the SO09 survey upper ocean temperatures had cooled to
3ndash4 1C across the section There was little change in salinity except in the northeast corner of Burger where low salinity (le30) waters protruded to the southwest
In August 2010 (A10) the upper 20 m included moderately warm (3ndash4 degC) low-salinity (lt30) meltwater pools interspersed within an otherwise homogeneous layer of warmer (5ndash6 degC) saltier (30ndash315) water The lower half of the water column contained cold (lt15 degC) salty (gt32) waters with the coldest and saltiest waters in Burger By the AS10 survey much of the winter water had been flushed from Klondike and replaced by a weakly stratified warm (6ndash8 degC) water column with salinities of ~315 In contrast Burger remained well stratified its surface waters had warmed only slightly since the A10 survey and there was little change in temperature and salinity of the bottom waters However the lower layer in Burger had thickened by ~10 m and the pycnocline had shoaled (but not weakened) by nearly 10 m The third survey included only Burger The upper half of the water column had freshened and cooled whereas bottom water properties registered little change
In 2011 water with temperatures between 35ndash7 degC and nearly uniform salinities of 315 occupied the upper 25 m of the entire transect Below 25 m depth warm waters occurred over the southwestern most portion (km 0 ndash 100) of the transect and were separated by a strong subsurface thermal front from much colder (325) waters to the northeast Properties in the upper 20 m in 2012 were substantially different especially between kilometers 100 and 300 Here cold (~1 degC) and fresh (lt30) waters derived from melting ice were separated from cold salty bottom waters by a strong but thin pycnocline Southwest of km 100 the upper 20 m were warm and moderately salty (~315) and were separated by a moderately strong pycnocline from colder saltier modified winter waters The upper ocean salinity distribution indicates a sequence of meltwater fronts at km 75 125 and 175 These fronts are baroclinically unstable and can generate eddies that transport warmer waters into the pycnocline The bolus of 25 degC water seen at km 225 is a possible signature of this process
Currents Time series of the meridional (V) and zonal (U) components of velocity at Klondike Burger and Crackerjack and the NARR wind velocity components in Klondike ( 7111 degN 16511 degW) for 1 Augustndash 6 October 2009 are plotted in Fig 11 and summary statistics given in Table 3 The plots include the near-surface record (~7 m depth) and the average of the two deep (~23 m and 35 m) records since there was little difference between these two
During a field campaign conducted during 1 Augustndash 6 October 2009 that generally covered the Klondike Burger and Crackerjack locations average winds were weak (~ 1 m sminus1) southwestward (248degT) and not significantly different from zero at the 95 confidence limit The mean currents within the Central Channel were north-northeastward at 5 cm sminus1 while those at Klondike were eastward at 4 cm sminus1 At both sites there was little current shear between the near- and sub-surface currents both on average and through time By contrast the flow at Burger was vertically sheared with southward flow of 5 cm sminus1 near the surface and southeastward flow of ~10 cm sminus1 at depth Although the mean flows were modest current speeds of 10ndash20 cm sminus1
were common with maximum values of ~40 cm sminus1 observed at Klondike and Burger over a 2-day period in early September Comparison of the mooring records at Klondike and Burger from
35
Figure 21 Location of Beaufort oceanographic records
September 8 to the end of the record is also of interest During this time the mean flow at all depths in Klondike was northward at 3 cm sminus1 At Burger the surface flow was southward at 5 cm sminus1 while the deeper flow was southeastward at ~10 cm sminus1
Oceanographic BEAUFORT SEA
Generally speaking there was not a great amount of oceanographic data available for the Beaufort Sea Seven records were located that covered years 1999 through 2004 They contained ~120000 data points for each of current speed current direction water temperature and salinity
Waves No wave date for the Beaufort Sea was located during this effort
Current Current Speed
A limited amount of current data was located for the Beaufort Sea The sample consisted of seven files with data collected from years 1999 to 2004 inclusive Current measurements were taken hourly and at depth between 3m and 9m Data was collected throughout the year Figure 21 shows the location where the samples were collected
Results from individual records are shown in Table 21 Table 22 is a summary for all the data Results shown are the mean and upper-end quantile values Figure 22 shows histograms of the data summary giving an indication of dispersion and frequency of the sample
36
Table 21 Current speed by record
Mean Record Name Latitude Longitude cms 95th 99th 999th Max O200108adcMcCl 70337 -147545 79 297 487 749 881 O200208adcArgo 70453 -148212 97 343 572 91 1246 O200208adcDink 70406 -147894 98 351 602 94 1164 O200208adcRein 70509 -14832 73 197 357 645 898 O200507adcSmit 70988 -154033 64 282 548 653 757 O200709adcCamd 70028 -144943 56 206 349 637 752 O200709adcCros 705 -147805 89 356 515 752 1073
Table 22 Summary of current speed samples
Mean Beaufort Sea Data Pts cms 95th 99th 999th 9999th Max all data 121617 81 296 526 814 1102 1246 Simpson Cluster 87048 9 324 554 861 1117 1246 O200507adcSmit 7883 64 282 548 653 757 757 O200709adcCamd 26849 56 206 349 637 746 752
Figure 22 Histograms for current speed summary
Current Direction
37
Figure 23 Current direction summary
Current direction was plotted and is summarized in the lsquocurrent rosersquo charts shown in Figure 23 From the figure it can be seen that east-west current are dominant These represent to direction the current is going to
Tidal Current No data for tidal current was located during this effort
Tide No tide data was located during this effort
38
Figure 24 Summary of salinity data
Wind-induced Surge No data for wind-induced surge was located during this effort
Water Salinity Salinity data was collected along with the current data described above The histograms in Figure 24 summarize the salinity data
Water Temperature Water temperature measurements were also collected with the current data Temperature measurements were taken at a depths of between 8m and 16m Figure 25 shown the distribution of water temperatures and summarizes the measurements The mean values shown refer to the statistical mean of the samples The mode value corresponds to the most common water temperature measured -18 C was the most common value
39
Figure 25 Water temperature summary
Seabed geotechnical ndash Ice-induced gouge Soil conditions vary throughout the region and description are best determined as part of a site-specific study No attempt was made to characterize the seabed soil conditions as part of this effort
Ice-induced gouge ice gouging is known to be prevalent in water shallower than the 60m and especially so in the so-called Stamukhi Zone A formal treatment of ice-gouging may be found in (C-CORE 2008) (C-CORE 2008) was a joint-industry-project (JIP) that focused specifically on ice gouging in the Chukchi and US Beaufort in the context of subsea pipeline construction
Seismic Earthquakes can occur in the nearshore region of the US Beaufort Figure 22-3 of (ASCE 2010) indicates that at approximately the shoreline in the Prudhoe Bay area a short period Ss (02s structure) Risk-Adjusted Maximum Considered Earthquake (MCER) Ground Motion Parameter of ~40g for 5 Critically Damped structure founded on a Site Class B The MCER appears to decrease in a radial pattern as one moves northward from this point A 1s structure in the same location will have an MCER of ~15g shown in Figure 22-4 of (ASCE 2010)
Because the offshore region is not as well studied as terrestrial location site-specific ground motion parameters may need to be established to establish a response spectrum for particular site Eg the Chapter 21 procedure of ACSE 7-10 to determine MCER Such information is
40
critical in determine the response of a structures during a seismic event Mapped MCER
generally do extend a great distance offshore
MCER values are for bedrock in the region Once established the values will have to be modified to account for the soil characteristics at the site in question The adjustment is generally based on the shear wave velocity of the soil underlying the construction Additional information about site classification may be found in (ASCE 10) Chapter 20
ASCE 7-10 generally relates to building structures on land and the reader is referred to ISO 19901-22004 for seismic design procedures and criteria for offshore structures
Oceanographic CHUKCHI SEA
For the Chukchi Sea forty-nine files of oceanographic data were acquired Seven of those files were strictly wave measurements The remaining files contained current speed current direction and water temperature and salinity measurements
Waves A limited amount of wave data was acquired for the Chukchi Sea During this study seven (7) files of wave measurements were acquired They were collected in years 2010 2011 and 2012 The files contain data for significant wave height maximum wave height peak wave period and wave direction Significant wave height is defined as the mean value of the highest third of the waves recorded in this case for each hour The maximum wave height is generally the maximum wave height recorded during each hour
Each of these values were recorded hourly Figure 26 is a map of the location where wave measurement were collected
Figure 26 Location of wave measurements
Wave Height
Wave measurement were separated by month July August September and October were the only months for which measurements were reported This generally corresponds to the lsquoopen waterrsquo season Table 23 and Figure 27 provide a summary of all the wave height data acquired during the project Figure 28 provides histograms of both significant wave height and maximum wave height by month
41
Figure 27 Summary of monthly wave heights
Table 23 Wave height summary wave heights in meters max
Data max max max max ht No Month Pts SWHmn SWHmax htmn ht95th ht99th ht999th recorded 7 July 131 06 17 1 26 3 3 3 8 Aug 2256 12 34 19 42 51 55 56 9 Sept 3608 15 42 24 48 61 73 84 10 Oct 685 13 4 22 4 54 59 59 - All 6680 13 42 22 46 58 71 84
42
Figure 28 Wave height histograms
Wave Period
Values for peak wave period we collected with the wave height data Peak wave period is defined as the wave period associated with the most energetic waves in the total wave spectrum For this sample the value corresponds to the most energetic waves during an hour of wave monitoring
43
Figure 29 Summary of monthly peak wave period data
Wave Direction
Results for wave period data were separated by month as well as combined An attempt was made to fit the combined data to the Normal Distribution The Probability plot appears favorable but did not pass a goodness-of-fit test Table 24 and Figure 29 summarize the peak wave period data
Table 24 Summary of peak wave period data
Month Tmin T1st T5th Tmean Tmode T95th T99th Tmax
Jul 19 2 22 41 4 63 65 66 Aug 21 27 35 56 6 77 85 91 Sep 19 25 42 7 7 95 111 125 Oct 34 38 47 65 6 83 91 95 All 19 26 38 64 6 91 105 125
Wave direction is shown on the charts in Figure 210 The July sample of wave measurements did not contain any direction data The charts reflect the direction if coming from
44
Figure 210 Wave direction charts
Current Current Speed
Thirty-eight files of oceanographic data were acquired for this study Most of the samples were collected between 1992 and 1995 inclusive with one set from 2003 Depth of the instruments were between 40m and ~100m Figure 211 shows the location where the samples were collected Tables 25 and 26 summaries current speed measurements
45
Figure 211 location of Oceanographic samples
Table 25 Summary of current speed data by region Chukchi Sea Mean Spd cms 95th 99th Eastern Data 277 639 846 Western Data 118 339 505
All Data 207 563 802
999th 976 732 956
9999th 1115 883
1098
Max Spd 1266 947
1266
46
Table 26 Summary of current speed for each record Mean Spd Max
Record Name Latitude Longitude cms 95th 99th 999th Spd O199209RCM1301 71052 -159546 367 613 842 1057 1124 O199209RCM1303 69012 -168489 74 164 24 34 401 O199209RCM2011 69017 -166959 84 193 278 321 333 O199209RCM3901 71052 -159546 325 584 732 883 947 O199209RCM4001 69012 -168489 92 226 307 392 418 O199209RCM4014 71052 -159546 179 312 33 333 333 O199209RCM5409 71332 -158166 284 527 699 812 876 O199209RCM5801 71332 -158166 314 653 842 932 999 O199209RCM5901 70661 -167027 117 238 305 357 389 O199209RCM6401 71332 -158166 325 646 803 915 954 O199209RCM6915 71332 -158166 227 423 57 676 729 O199209RCM6991 69017 -166959 10 25 345 414 457 O199209RCM7312 70661 -167027 76 156 234 289 326 O199209RCM9220 71332 -158166 14 273 307 331 333 O199309RCM5410 7103 -159567 403 899 952 969 97 O199309RCM6916 7103 -159567 322 606 737 1031 1113 O199309RCM9221 7103 -159567 46 248 318 333 333 O199409RCM1201 71054 -159532 356 764 956 1081 1136 O199409RCM1302 71165 -159743 209 482 685 982 1054 O199409RCM2001 71054 -159532 296 496 749 935 99 O199409RCM3902 71165 -159743 211 363 453 895 895 O199409RCM4002 71001 -17457 93 194 228 268 286 O199409RCM5802 70661 -167016 10 284 345 389 421 O199409RCM6402 71279 -164272 88 187 235 33 334 O199509RCM1500 71346 -15762 27 633 857 1162 1267 O199509RCM1502 71346 -15762 231 409 496 717 813 O199509RCM5203 71255 -157523 156 429 656 828 967 O199509RCM5270 70617 -167084 109 264 348 464 491 O199509RCM5330 71335 -164453 8 165 209 31 325 O199509RCM5350 71685 -16719 69 162 229 296 319 O199509RCM5902 6999 -166225 66 183 232 278 331 O199509RCM6916 71052 -159528 323 608 699 841 941 O199509RCM9222 71415 -157745 194 434 556 671 707 O199609RCM0102 70751 -163291 125 235 348 464 505 O199609RCM0402 71346 -15762 25 563 738 918 976 O199609RCM0502 71346 -15762 248 496 618 813 863 O199609RCM5133 7105 -159527 404 807 877 944 964 O200309rcmsbi4 73611 -166042 59 141 217 291 325
47
Figure 212 demonstrates the dispersion and frequency of the current speed data
Figure 212 Histograms of current speed data
Current Direction
Figure 213 shows the directionality of the current data The charts show the direction the current is going to
Figure 213 Current direction charts
Tidal Current No data for tidal current was located during this effort
Tide No tide data was located during this effort
Wind-induced Surge No data for wind-induced surge was located during this effort
Salinity Salinity data was collected along with the current data described above The histograms in Figure 214 summarize the salinity data
48
Figure 214 Summary of salinity data
Water Temperature No useable surface water temperature data was located in this effort However a considerable amount of data at depth was located Depth of the instruments used to collect temperature data were from 40m to ~100m These were the same instrument used to collect the current data Figure 215 summarizes the water temperature data
49
Figure 215 Summary of water temperature at depths ranging from 40m to ~100m
Seabed geotechnical ndash Ice-induced gouge (See corresponding comments for Beaufort Sea)
Seismic Earthquakes can occur in the nearshore region of the US Beaufort Figure 22-3 of (ASCE 2010) indicates that at southern portion of the Chukchi Sea (as one nears the Bering Strait) a short period Ss (02s structure) Risk-Adjusted Maximum Considered Earthquake (MCER) Ground Motion Parameter of ~35g for 5 Critically Damped structure founded on a Site Class B The MCER be minimal off the North Slope gradually increasing as one moves toward the Bering Strait The 1s MCER is proportionally smaller as well
See additional comments in the corresponding section for the Beaufort Sea
50
Section 3 Limitations amp Recommendations
Meteorological Data
In general a robust sample of wind and temperature measurements were located for this project Wind speed is necessary for determining wind loads on structures Temperature information is also necessary for a number of instances in the design of offshore structures This would include fracture toughens requirements for steel as well as cold temperature performance of mechanical and electrical systems
During this effort we were unable to locate any reliable precipitation information This information can be critical in terms of rain and snow loads for the design of structures BSEE may wish to consider filling this gap in knowledge in subsequent studies
Oceanographic Data
Oceanographic data for the Beaufort Sea is sparse and not readily available A reasonably sized sample for current water temperature and salinity was acquired However most of the sample is relatively close to shore
Perhaps the most critical parameter in terms of design of offshore structures that was missing from the sample is wave data Wave data in the region is quite scarce Acquiring wave information should be a priority for future oceanographic studies in the region A technical point of concern is the manner in which wave data is typically disseminated The Scientific Community generally characterizes wave environments by Significant Wave Height ndash the mean of the top 13 of wave heights measured over some timeframe In the context of forces [actions] from waves the extreme quantiles are of greatest concern Identifying the extremes should be a priority in any future work Because extremes are by definition rare multiple seasons of monitoring at a particular site are warranted As an alternative a smaller sample of wave data may be used to inform regional wave modeling Such modeling can provide values for extreme wave conditions but prudence requires they still be vetted with actual measurements
Wave period is another critical parameter for offshore structure design and offshore operations Knowing the most dominant wave periods will allow operators to assess the vulnerability of an offshore structure or vessel to excitation by waves If the dominant wave period(s) are near a natural frequency of the structure or vessel (Eg natural period of roll or pitch) excessive deformation or movement may occur
In general the designer of an offshore structures in this region is most concerned with external actions sources of external forces In the context of metocean the most critical sources of external lateral forces are wind current waves Design values associated with any of these parameters must come from a reliable sources with an understanding of the uncertainty associated with those values is one is to implement the ISO 19906 normative
Tables 31 through 34 show a comparison of the parameters from this study to the values provided in annexes B7 and B8 of ISO 19906
51
‐ ‐
‐ ‐
‐ ‐
‐ ‐
‐ ‐
Table 31 Comparison for Beaufort meteorological parameters B7 Beaufort Meteorological Parameters
Parameter Max (deg C)
Air Temp Min Freezing days Thawing days
Wind Speed
Wind Direct Winter
Summer Precipitation Rainfall (mm)
Snowfall
Visibility days lt 5mi
ISO 199
Average Annual Value
20 ‐30 4500 ‐
24 95
degrees 50 N and NW 150 750
20 of time
06 Annex B7
Range of Values
10 to 30 ‐20 to ‐40
3500 to 5500 ‐
18 to 32
‐
‐
100 to 200 600 to 1100
‐
BSEE E13PC00014 Study
Average Annual Value Range of Values 105 ‐35 to 252 ‐28 ‐3 to ‐479 4180 ‐
440 ‐
67 329 (max)
generally east‐west year round
‐ ‐
‐ ‐
‐ ‐
Table 32 Comparison for Chukchi meteorological parameters B8 Chukchi Meteroligical Parameters
Parameter Max (deg C)
Air Temp Min Freezing days Thawing days
Wind Speed
Wind Direct Winter Summer
Precipitation Rainfall (mm) Snowfall
Visibility days lt 5mi
ISO 19906 Annex B8 NE Region
Average Range of Annual Value Values
16 10 to 20 ‐44 ‐40 to ‐50 4000 3500 to 4500
SE25 to 30 ‐
deg E 25 to 40 deg ‐
157 100 to 200 530 300 to 700
gt30 of time 20 to 40
BSEE E13PC00014 Study
Average Annual Value Range of Values
105 ‐35 to 252 ‐28 ‐39 to ‐483 4070 ‐
460 ‐
58 277 (max)
genrally E‐NE to W‐SW
52
‐ ‐
Table 33 Comparison for Beaufort oceanographic parameters B7 Beaufort Oceanographic Parameters
Parameter Waves (gt100m water depth)
Current
Water Salinity Water Temperature
Seabed geotech ice gouge
Seimic
max wave ht (m) sig wave height period near‐surface max cms bottom max Average Surface ppt summer surface max (deg C)
‐summer surface ave gouge depth (m) water dpeth (m) magnitude
ISO 19906 Annex B7 Average
Range of Annual
ValuesValue
‐
37 18 to 85 67 45 to 98 40 20 to 100
2 to 5 1 to 50 ‐2 to 30 0 to 33 ‐10 2 to 12
5 to 7 0 to 10 ‐
06 01 to 5 ~30 ~50 3 to 5 55 amp 65
BSEE E13PC00014 Study
Average Range of Values
Annual Value
‐
‐
81 1246 (max) ‐
312 14 to 37 at depth Mean ‐12 Mode ‐18
Max 57
see notes in Section 2
53
Table 34 Comparison for Chukchi oceanographic parameters B8 Chukchi Oceanographic Parameters
Parameter Waves (gt100m water depth) max wave ht (m)
sig wave height period
Current near‐surface max cms bottom max
Water Salinity Average Surface ppt Water Temperature summer surface max (deg C) ‐
summer surface ave Seabed geotech ice gouge gouge depth (m)
water dpeth (m) Seimic magnitude
ISO 19906 Annex B7
Average Range of Values
Annual Value
‐
37 18 to 85 67 45 to 98 40 20 to 100
2 to 5 1 to 50 2 to 30 0 to 33 10 2 to 12
5 to 7 0 to 10 06 01 to 5
‐~30 ~50 3 to 5 55 amp 65
BSEE E13PC00014 Study
Average Range of Annual Value Values
22 84 13 up to 42 64 19 to 125 207 1266 (max)
‐
326 (at depth) 247 to 404 at depth Mean ‐11 Mode ‐
18 Max 91
see notes in Section 2
54
Section 4 Source Data Narratives
This section is a detailed list of the data sources used for this project
Metrological data Narrative BEAUFORT SEA
buo48211csv
Date uploaded 3232014 Owned and maintained by Shell Arctic Moored meteorological buoy (Shell Arctic) Camden Bay Beaufort Sea Organized as follows station_id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute WDIR (deg) WSPD (ms) GST (ms) PRES (hPa) ATMP (degC) WTMP (degC) 70370 N 146040 W (70deg2212 N 146deg223 W) No elevation height listed No data for last 45 days or more WDIR ndash Wind direction (the direction the wind is coming from in degrees clockwise from true N) during the same period used for WSPD WSPD - Wind speed (ms) averaged over an eight-minute period for buoys and a two-minute period for land stations Given Hourly GST - Peak 5 or 8 second gust speed (ms) measured during the eight-minute or two-minute period PRES - Sea level pressure ATMP - Air temperature WTMP - Sea surface temperature Note Values of 99999 are NULL httpwwwndbcnoaagovstation_pagephpstation=48211 buo48212csv Date uploaded 3232014 Owned and maintained by Shell Arctic Moored meteorological buoy (Shell Arctic) Harrison Bay Beaufort Sea Organized as follows station_id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute WDIR (deg) WSPD (ms) GST (ms) PRES (hPa) ATMP (degC) WTMP (degC) 70874 N 150279 W (70deg5227 N 150deg1646 W) No elevation height listed No data for last 45 days or more WDIR ndash Wind direction (the direction the wind is coming from in degrees clockwise from true N) during the same period used for WSPD WSPD - Wind speed (ms) averaged over an eight-minute period for buoys and a two-minute period for land stations Given Hourly GST - Peak 5 or 8 second gust speed (ms) measured during the eight-minute or two-minute period PRES - Sea level pressure ATMP - Air temperature (Celsius) WTMP - Sea surface temperature (Celsius) Note Values of 99999 are NULL httpwwwndbcnoaagovstation_pagephpstation=48212 buoPRDA2csv
55
Date uploaded 3232014 Owned and maintained by NOAArsquos National Ocean Service Moored meteorological buoy (9497645) Prudhoe Bay Beaufort Sea Organized as follows station_id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute WDIR (deg) WSPD (ms) GST (ms) PRES (hPa) ATMP (degC) WTMP (degC) 70400 N 148527 W (70deg240 N 148deg3136 W) Ongoing data Air temp height 2368 m above site elevation Anemometer height 5386 m above site elevation Barometer elevation 45 m above mean sea level Sea temp depth 326 m below site elevation WDIR ndash Wind direction (the direction the wind is coming from in degrees clockwise from true N) during the same period used for WSPD WSPD - Wind speed (ms) averaged over an eight-minute period for buoys and a two-minute period for land stations Given Hourly GST - Peak 5 or 8 second gust speed (ms) measured during the eight-minute or two-minute period PRES - Sea level pressure ATMP - Air temperature WTMP - Sea surface temperature Note Values of 99999 are NULL httpwwwndbcnoaagovstation_pagephpstation=prda2 Data uploaded 05092014 Values ldquo999rdquo for WDIR WTMP and ATMP changed to ldquo99999rdquo Values ldquo9999rdquo for PRES changed to ldquo99999rdquo
Auroracsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL Barter_Islandcsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL Belchercsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E)
56
Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL BOEM Buoycsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL Cabotcsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL Cottle Islandcsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL Cross Islandcsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL
57
Drew_Pointcsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL
Endicottcsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL Fireweedcsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL Galahadcsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL Komakuk Beach Autocsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg)
58
Kuvlum2csv
Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL
Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL Kuvlum3csv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL Lonelycsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL McCoveycsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL Northstarcsv
59
Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL
Phoenixcsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL
Point Thompsoncsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL Prudhoe Baycsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL Pt_McIntyre_Pad_2csv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow
60
Wild_Weasalcsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL
Depth (cm) Note Values of -999 are NULL Reindeer Islandcsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL SEDNAcsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL
Shell Buoy Beaufort 09csv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL
61
CHUKCHI SEA
buo48012csv Date uploaded 162014 Owned and maintained by University of Alaska Fairbanks Moored meteorological buoy (UAF) Point Lay Chukchi Sea Organized as follows station_id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute WDIR (deg) WSPD (ms) GST (ms) PRES (hPa) ATMP (degC) WTMP (degC) 70026 N 166069 W (70deg134 N 166deg410 W) No elevation height listed WDIR ndash Wind direction (the direction the wind is coming from in degrees clockwise from true N) during the same period used for WSPD WSPD - Wind speed (ms) averaged over an eight-minute period for buoys and a two-minute period for land stations Given Hourly GST - Peak 5 or 8 second gust speed (ms) measured during the eight-minute or two-minute period PRES - Sea level pressure ATMP - Air temperature WTMP - Sea surface temperature Note Values of 99999 are NULL httpwwwndbcnoaagovstation_pagephpstation=48012
buo48213csv Date uploaded 162014 Owned and maintained by Shell Arctic Moored meteorological buoy (MOB2) Burger Chukchi Sea Organized as follows station_id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute WDIR (deg) WSPD (ms) GST (ms) PRES (hPa) ATMP (degC) WTMP (degC) 71758 N 167952 W (71deg4530 N 167deg578 W) No elevation height listed WDIR ndash Wind direction (the direction the wind is coming from in degrees clockwise from true N) during the same period used for WSPD WSPD - Wind speed (ms) averaged over an eight-minute period for buoys and a two-minute period for land stations Given Hourly GST - Peak 5 or 8 second gust speed (ms) measured during the eight-minute or two-minute period PRES - Sea level pressure ATMP - Air temperature WTMP - Sea surface temperature Note Values of 99999 are NULL httpwwwndbcnoaagovstation_pagephpstation=48213
buo48214csv Date uploaded 162014 Owned and maintained by Shell Arctic Moored meteorological buoy (MOB1) Klondike Chukchi Sea Organized as follows station_id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute WDIR (deg) WSPD (ms) GST (ms) PRES (hPa) ATMP (degC) WTMP (degC) 70871 N 165246 W (70deg5217 N 165deg1447 W) No elevation height listed WDIR ndash Wind direction (the direction the wind is coming from in degrees clockwise from true N) during the same period used for WSPD
62
WSPD - Wind speed (ms) averaged over an eight-minute period for buoys and a two-minute period for land stations Given Hourly GST - Peak 5 or 8 second gust speed (ms) measured during the eight-minute or two-minute period PRES - Sea level pressure ATMP - Air temperature WTMP - Sea surface temperature Note Values of 99999 are NULL httpwwwndbcnoaagovstation_pagephpstation=48213
O201210buo8211csv [this was moved from the oceanographic data folder atm 3152014] This is data from the Shell Camden Bay meteorological Buoy The data is organized into the following fields station_id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute depth (meters) windto_direction (degrees) windspeed (ms)airtemperature (Celsius) watertemperature (Celsius) Web page here httpwwwndbcnoaagovstation_pagephpstation=48211
M201312METPABRcsv This file describes a re-processing of meteorological data from Barrow Alaska Meteorological data (wind speed direction and air temperature data) were obtained from the National Climate Data Center (httpwwwncdcnoaagov) Wind speed and direction measurements begin in 1940 with twice daily observations the recording interval was changed to hourly in mid-1946 Data resolution and quality changes through the years with different observers and different automated instrumentation systems in use Missing data is denoted by NaN The station name is officially referred to as 700260 Wiley Post Barrow AK it is located at +71283 North Latitude -156782 West Longitude
Approx Locationcsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL
Barrowcsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm)
63
Note Values of -999 are NULL Cape Kjangtokjnmankcsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL
Cape_Lisburnecsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL Conoco Buoycsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL
Conoco Shipcsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL Crackerjackcsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed
64
(ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL Diamondcsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL
Mys Billingsacsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL Point_Laycsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL Popcorncsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL
65
Red Dog Dockcsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL
Shell Buoy Chukchi 08csv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL Shell Buoy Chukchi 09csv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL Wainwright Permcsv Date uploaded 1152015 Organized as follows Year Month Day Hour (UTC) Minute Latitude (N) Longitude (E) Elevation (m) Temperature (deg C) Dew Point (deg C) Relative Humidity () Wind Speed (ms) Wind Direction (deg) Station Pressure (hPa) Sea-Level Pressure (hPa) Altimeter (in Hg) Downward Shortwave Radiation (Wm^2) Downward Longwave Radiation (Wm^2) 1-Hour Accumulated Precipitation (mm) 6-Hour Precipitation (mm) 24-Hour Precipitation (mm) Snow Depth (cm) Note Values of -999 are NULL
66
Oceanographic data narrative
his folder describes origin content and location of ocean data files All units in metric [m = meters degTr = degrees true UTC = Coordinated Universal Time C = degrees Celsius N = North W = West E= East PSU= Practical Salinity Unit]
---------
O201210buo8211csv
[This was moved to the meteorological data folder atm 3152014] This is data from the Shell Camden Bay meteorological Buoy The data is organized into the following fields station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute depth (m) wind to direction (degrees) wind speed (ms) air temperature (C) water temperature (C) Web page here httpwwwndbcnoaagovstation_pagephpstation=48211
O200309rcmsbi4csv
Moored current meter data from the Shelf Basin Interaction study Location 73611 N 166042 W Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute instrument depth (m) water current to direction (degTr) water current speed (ms)
O201212WLV1094csv
Water level data from 2006 ndash 2012 collected at the NOAA National Ocean Service site at the Red Dog Mine Location 71050 N 159527 W Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Water Level (m)
O199209RCM1301csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (C) Salinity (PSU) Direction Speed (cms)
O199209RCM1303csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199209RCM2011csv
67
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199209RCM3901csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199209RCM4001csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199209RCM4014csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199209RCM5409csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199209RCM5801csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199209RCM5901csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199209RCM6401csv
68
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199209RCM6915csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199209RCM6991csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199209RCM7312csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199209RCM9220csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199309RCM5410csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199309RCM6916csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199309RCM9221csv
69
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199409RCM1201csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199409RCM1302csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199409RCM2001csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199409RCM3902csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199409RCM4002csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199409RCM5802csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199409RCM6402csv
70
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199509RCM1500csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199509RCM1502csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199509RCM5203csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199509RCM5270csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199509RCM5330csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199509RCM5350csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199509RCM5411csv
71
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199509RCM5902csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199509RCM6916csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199509RCM9222csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199609RCM0022csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199609RCM0032csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199609RCM0102csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199609RCM0402csv
72
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199609RCM0502csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199609RCM5133csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O199609RCM6393csv
Moored current meter temperature and salinity data collected in the Chukchi Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Depth (m) Temperature (degC) Salinity (PSU) Direction Speed (cms)
O201009buoo101csv
Moored wave gauge data collected in the Chukchi Sea Organized as follows year month day hour (UTC) minute latitude (degrees north) longitude (degrees west) significant wave height (m) maximum wave height (m) peak wave period (sec) and wave direction (degrees from true north) Gaps in the data time series are represented by the value NaN
O201009buoo102csv
Moored wave gauge data collected in the Chukchi Sea Organized as follows year month day hour (UTC) minute latitude (degrees north) longitude (degrees west) significant wave height (m) maximum wave height (m) peak wave period (sec) and wave direction (degrees from true north) Gaps in the data time series are represented by the value NaN
O201110buoMOB2csv
Moored wave gauge data collected in the Chukchi Sea Organized as follows year month day hour (UTC) minute latitude (degrees north) longitude (degrees west) significant wave height (m) maximum wave height (m) peak wave period (sec) and wave direction (degrees from true north) Gaps in the data time series are represented by the value NaN
O201210buoB101csv
73
Moored wave gauge data collected in the Chukchi Sea Organized as follows year month day hour (UTC) minute latitude (degrees north) longitude (degrees west) significant wave height (m) maximum wave height (m) peak wave period (sec) and wave direction (degrees from true north) Gaps in the data time series are represented by the value NaN
O201210buoB102csv
Moored wave gauge data collected in the Chukchi Sea Organized as follows year month day hour (UTC) minute latitude (degrees north) longitude (degrees west) significant wave height (m) maximum wave height (m) peak wave period (sec) and wave direction (degrees from true north) Gaps in the data time series are represented by the value NaN
O201210buoB103csv
Moored wave gauge data collected in the Chukchi Sea Organized as follows year month day hour (UTC) minute latitude (degrees north) longitude (degrees west) significant wave height (m) maximum wave height (m) peak wave period (sec) and wave direction (degrees from true north) Gaps in the data time series are represented by the value NaN
O200208adcArgocsv
Moored current meter (ADCP) temperature and salinity data collected near Argo Island in the Beaufort Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Current Measurement Depth (topmost bin in m) Direction Speed (cms) CTD Depth (m) Temperature (degC) Salinity (PSU)
O200208adcDinkcsv
Moored current meter (ADCP) temperature and salinity data collected near Dinkum Island in the Beaufort Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Current Measurement Depth (topmost bin in m) Direction Speed (cms) CTD Depth (m) Temperature (degC) Salinity (PSU)
O200108adcMcClcsv
Moored current meter (ADCP) temperature and salinity data collected near McClure Island in the Beaufort Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Current Measurement Depth (topmost bin in m) Direction Speed (cms) CTD Depth (m) Temperature (degC) Salinity (PSU)
O200208adcReincsv
Moored current meter (ADCP) temperature and salinity data collected near Reindeer Island in the Beaufort Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Current Measurement Depth (topmost bin in m) Direction Speed (cms) CTD Depth (m) Temperature (degC) Salinity (PSU)
74
O200709adcCamdcsv
Moored current meter (ADCP) temperature and salinity data collected near Camden Bay in the Beaufort Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Current Measurement Depth (topmost bin in m) Direction Speed (cms) CTD Depth (m) Temperature (degC) Salinity (PSU)
O200709adcCroscsv
Moored current meter (ADCP) temperature and salinity data collected near Cross Island in the Beaufort Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Current Measurement Depth (topmost bin in m) Direction Speed (cms) CTD Depth (m) Temperature (degC) Salinity (PSU)
O200507adcSmitcsv
Moored current meter (ADCP) temperature and salinity data collected near Smith Island in the Beaufort Sea Organized as follows station id latitude (degrees north) longitude (degrees west) year month day hour (UTC) minute Current Measurement Depth (topmost bin in m) Direction Speed (cms) CTD Depth (m) Temperature (degC) Salinity (PSU)
Oceanographic Data Narrative ndash Wave Buoy Stations in Chukchi Sea Significant wave height (meters) is calculated as the average of the highest one-third of all of the wave heights during the 20-minute sampling period Maximum wave height (meters) is calculated as the average of the highest 110 waves Peak wave period wave period (seconds) is the period with the maximum wave energy Wave direction is the direction from which the waves at the dominant period (DPD) are coming The units are degrees from true North increasing clockwise with North as 0 (zero) degrees and East as 90 degree
O201212WLV1094wavecsv
Organized as follows year month day hour (UTC) minute latitude (degrees north) longitude (degrees west) Significant Wave Height (m) Maximum Wave Height (m) Peak Wave Period (s) Wave Direction (degrees from true North)
O201009buoo101wavecsv
Organized as follows year month day hour (UTC) minute latitude (degrees north) longitude (degrees west) Significant Wave Height (m) Maximum Wave Height (m) Peak Wave Period (s) Wave Direction (degrees from true North)
O201009buoo102wavecsv
75
Organized as follows year month day hour (UTC) minute latitude (degrees north) longitude (degrees west) Significant Wave Height (m) Maximum Wave Height (m) Peak Wave Period (s) Wave Direction (degrees from true North)
O201110buoMOB2wavecsv
Organized as follows year month day hour (UTC) minute latitude (degrees north) longitude (degrees west) Significant Wave Height (m) Maximum Wave Height (m) Peak Wave Period (s) Wave Direction (degrees from true North)
O201210buoB101wavecsv
Organized as follows year month day hour (UTC) minute latitude (degrees north) longitude (degrees west) Significant Wave Height (m) Maximum Wave Height (m) Peak Wave Period (s) Wave Direction (degrees from true North)
O201210buoB102wavecsv
Organized as follows year month day hour (UTC) minute latitude (degrees north) longitude (degrees west) Significant Wave Height (m) Maximum Wave Height (m) Peak Wave Period (s) Wave Direction (degrees from true North)
O201210buoB103wavecsv
Organized as follows year month day hour (UTC) minute latitude (degrees north) longitude (degrees west) Significant Wave Height (m) Maximum Wave Height (m) Peak Wave Period (s) Wave Direction (degrees from true North)
76
Section 5 Bibliography
Aagaard K T J Weingartner SL Danielson RA Woodgate G C Johnson T E Whitledge (2006) Some controls on flow and salinity in Bering Strait Geophysical Research Letters 33 L19602 doi1010292006GL026612
ASCE 7-10 (2010) ldquoMinimum Design Loads for Building and Other Structuresrdquo American Society of Civil Engineers Reston VA
Baule WJ and MD Shulski (2014) Climatology and trends of wind speed in the BeaufortChukchi Sea coastal region from 1979 to 2009 International Journal of Climatology 34101002joc201434issue-8 2819-2833
Carmack E P Winsor and W Williams (2015) The contiguous riverine coastal domain Progress in Oceanography in press
Cassano E Lynch A Cassano J and Koslow M (2006) Classification of synoptic patterns in the western arctic associated with extreme events at barrow Alaska USA Climate Research 30 pp 83ndash97
C-CORE (2008) Design Options for Offshore Pipelines in the US Beaufort and Chukchi Seas Prepared for Minerals Management Service US Department of the Interior Prepared by C-CORE Report No R- 07-078-519 v20 April 2008
Coachman LK Aagaard K and Tripp (1975) RB Bering Strait The Regional Physical Oceanography 172 pp University of Washington Press Seattle Washington
CPC (2016) Climate Prediction Center National Weather Service National Oceanic and Atmospheric Administration httpwwwcpcncepnoaagov
Dmitrenko I A et al (2010) Observations of supercooling and frazil ice formation in the Laptev Sea coastal polynya Journal of Geophysical Research-Oceans 115 Artn C05015 Doi 1010292009jc005798
Druckenmiller ML H Eicken J C George L Brower (2013) Trails to the whale Reflections of change and choice in an Intildeupiaq icescape Polar Geography 36 5-29
Druckenmiller M L H Eicken M A Johnson D J Pringle and C C Williams (2009) Toward an integrated coastal sea-ice observatory System components and a case study at Barrow Alaska Cold Regions Science and Technology 56(2-3) 61-72 Doi 101016JColdregions 200812003
Drucker R Martin S and Moritz R (2003) Observations of ice thickness and frazil ice in the St Lawrence Island polynya from satellite imagery upward looking sonar and salinitytemperature moorings Journal of Geophysical Research-Oceans 108 doi 1010292001JC001213 issn 0148-0227
Eicken H Kaufman MR Krupnik I Pulsifer P Apangalook L Apangalook P Weyapuk Jr W Leavitt J (2014) A framework and database for community sea ice observations in a changing Arctic An Alaskan prototype for multiple users Polar Geography 37 5-27
Eicken H A L Lovecraft and M L Druckenmiller (2009) Sea-ice system services A framework to help identify and meet information needs relevant for Arctic observing networks Arctic 62(2) 119-136
77
Francis OP and DE Atkinson (2012) Synoptic forcing of wave state in the southeast Chukchi Sea Alaska at an offshore location Natural Hazards Volume 62 Number 3 1169-1189
Fukamachi Y G Mizuta K I Ohshima T Toyota N Kimura and M Wakatsuchi (2006) Sea ice thickness in the southwestern Sea of Okhotsk revealed by a moored ice-profiling sonar Journal of Geophysical Research-Oceans 111(C9) Artn C09018 Doi 1010292005jc003327
George J C H P Huntington K Brewster H Eicken D W Norton R Glenn (2004) Observations on shorefast ice dynamics in Arctic Alaska and the responses of the Intildeupiat hunting community Arctic 57(4) 363-374
Johnson MA Eicken H Druckenmiller ML Glenn R (2014) Experts Workshops to Comparatively Evaluate Coastal Currents and Ice Movement in the Northeastern Chukchi Sea Barrow and Wainwright Alaska March 11-15 2013 University of Alaska Fairbanks Fairbanks Alaska 48pp
Ladd C Bond N (2002) Evaluation of the NCEPNCAR reanalysis in the NE Pacific and the Bering Sea Journal of Geophysical Research-Oceans 107 (C10) doi1010292001JC001157
Leonard G H C R Purdie P J Langhorne T G Haskell M J M Williams and R D Frew (2006) Observations of platelet ice growth and oceanographic conditions during the winter of 2003 in McMurdo Sound Antarctica Journal of Geophysical Research-Oceans - Doi 1010292005JC002952
Liu Y P MacCready BM Hickey EP Dever PM Kosro and M Banas (2009) Evaluation of a coastal ocean circulation model for the Columbia River plume in summer 2004 Journal of Geophysical Research-Oceans 114
Lynch A H Cassano E N Cassano J J and Lestak L R (2003) Case studies of high wind events in barrow Alaska Climatological context and development processes Monthly Weather Review 131(4) pp 719ndash732
Marko J R (2003) Observations and analyses of an intense waves-in-ice event in the Sea of Okhotsk Journal of Geophysical Research-Oceans 108(C9) 1010292001JC001214
Markus T J C Stroeve and J Miller (2009) Recent changes in Arctic sea ice melt onset freezeup and melt season length Journal of Geophysical Research-Oceans 114 C12024 Doi 1010292009jc005436
Mesinger F and 19 Coauthors (2006) North American regional re-analysis Bulletin of the American Meteorological Society 87 343ndash360
Mesquita MDS and DE Atkinson KI Hodges (2010) Characteristics and variability of storm tracks in the North Pacific Bering Sea and Alaska J Clim 23294ndash311
Moirera P (2011) Mesoscale modeling study of a polar low in the Chukchi and Beaufort Seas University of Alaska Fairbanks MS Thesis
Nelson RK 1969 Hunters of the northern ice University of Chicago Press Chicago
NDBC (2014) National Data Buoy Center httpwwwndbcnoaagov
NSIDC (2016) National Snow amp Ice Data Center httpsnsidcorgcryospherearctic-meteorologyindexhtml
PL Parker CD Wirick PG Shuert JM Grebmeier AM Springer RD Tripp DA
78
Hansell S Djenedi E Deleersnijder K Henriksen BA Lund P Andersen FE Muumlller-Karger and K Dean (1989) Carbon and nitrogen cycling within the BeringChukchi seas Source regions for organic matter affecting AOU demands of the Arctic Ocean Progress in Oceanography 22 277-359
Pickart RS T Weingartner LJ Pratt S Zimmermann and D J Torres (2005) Flow of winter- transformed Pacific water into the western Arctic Deep-Sea Research Pt II 52 3175 - 3198
Rasmussen EA and J Turner (2003) Polar Lows Mesoscale Weather Systems in the Polar Regions Cambridge University Press 624 pp
Schweiger A J (2004) lsquoChanges in seasonal cloud cover over the arctic seas from satellite and surface observationsrsquo Geophysical Research Letters 31(12)
Shimada K T Kamoshida M Itoh S Nishino E Carmack F McLaughlin S Zimmermann A Proshutinsky (2006) Pacific Ocean inflow Influence on catastrophic reduction of sea ice cover in the Arctic Ocean Geophysical Research Letters 33(8) doi101029 2005GL025624L08605
Shroyer E L and A J Plueddemann Wind-driven modification of the Alaskan coastal current Journal of Geophysical Research accepted
Spall M A (2007) Circulation and water mass transformation in a model of the Chukchi Sea Journal of Geophysical Research-Oceans 112 C05025doi1010292005JC002264
Stegall ST and J Zhang (2012) Wind field climatology changes and extremes in the chukchindash beaufort seas and alaska north slope during 1979ndash2009 J Climate 25 8075ndash8089
Tamura T K I Ohshima T Markus D J Cavalieri S Nihashi and N Hirasawa (2007) Estimation of thin ice thickness and detection of fast ice from SSMI data in the Antarctic Ocean Journal of Atmospheric and Oceanic Technology 24(10) 1757-1772 Doi 101175Jtech21131
Timmermans M-L and P Winsor (2012) Scales of density structure in the Chukchi Sea surface layer Continental Shelf Research 52 39-45 doi101016jcsr201210015
Walsh J E Chapman WL Portis D (2009) Arctic cloud fraction and radiative fluxes in atmospheric reanalyses Journal of Climate 22 2316ndash2334
Walsh JJ CP McRoy LK Coachman JJ Goering JJ Nihoul TE Whitledge TH Blackburn
Wang X L Feng Y Swail V R and Cox A (2015) Historical changes in the Beaufortndash ChukchindashBering seas surface winds and waves 1971ndash2013 Journal of Climate 28(19) pp 7457ndash7469
Weingartner T K Aagaard R Woodgate S Danielson Y Sasaki and D Cavalieri (2005) Circulation on the North Central Chukchi Sea Shelf Deep-Sea Research Pt II 52 3150-3174 doi101016jdsr2200510015
Weingartner T E Dobbins S Danielson R Potter H Statscewich and P Winsor (2013) Hydrographic variability over the northeastern Chukchi Sea shelf in summer-fall 2008ndash2010 Continental Shelf Research httpdxdoiorg101016jcsr201303012
Weingartner T J P Winsor R Potter H Statscewich and E Dobbins (2012) Application of
79
High Frequency Radar to Potential Hydrocarbon Development Areas in the Northeast Chukchi Sea OCS Study BOEM 2012-079 Final Report Bureau of Ocean Energy Management Anchorage Ak 165 p
Winsor P and D C Chapman (2004) Pathways of Pacific Water across the Chukchi Sea A numerical model study Journal of Geophysical Research-Oceans 109 C03002 doi 10292003JC001962
Woodgate RA KAagaard TJ Weingartner (2006) Interannual changes in the Bering Strait fluxes of volume heat and freshwater between 1991 and 2004Geophysical Research Letters 33 L15609 1010292006GL026931
Woodgate R A K Aagaard and T Weingartner (2005) A Year in the Physical Oceanography of the Chukchi Sea moored measurements from autumn 1990-91 Deep-Sea Research Pt II 52 3116-3149
Woodgate RA TJ Weingartner and R Lindsay (2012) Observed increases in Bering Strait oceanic fluxes from the Pacific to the Arctic from 2001 to 2011 and their impacts on the Arctic Ocean water column JGeophysRes 39 L24603 doi1010292012GL054092 2012
Wu Q J Zhang X Zhang W Tao (2014) Interannual Variability and Long-Term Changes of Atmospheric Circulation over the Chukchi and Beaufort Seas Journal of Climate 2713 4871-4889
Yu Y and D Rothrock (1996) Thin ice thickness from satellite thermal imagery Journal of Geophysical Research-Oceans 101(C11) 25753-25766
Zhang J F Liu W Tao J Krieger M Shulski and X Zhang (2016) Mesoscale Climatology and variation of surface winds over the Chukchi-Beaufort coastal areas Journal of Climate p 160128144619003 doi 101175jcli-d-15-04361
Zhang X JE Walsh J Zhang US Bhatt and M Ikeda (2004) Climatology and interannual variability of Arctic cyclone activity 1948-2002 Journal of Climate 17 2300-2317
Zhang X J Zhang J Krieger and M Shulski (2013) Beaufort and Chukchi Seas Mesoscale Meteorology Modeling Study Final Report Prepared for the Bureau of Ocean Energy Management Access Number 00018 wwwdataboemgovPIPDFImagesESPIS55301pdf
80
- Final Report BSEE contract No E13PC00014
-
- Abstract
-
- Abstract
- The intent of this project was to produce information that will facilitate implementation of the ISO 19906 Standard Petroleum and Natural Gas Industries - Arctic Offshore Structures (ie the Normative) The information collected in this effort consists of meteorological and oceanographic (metocean) information for US waters in both the Chukchi and Beaufort seas in a format consistent with the philosophy of the Normative Currently implementation of ISO 19906 in US waters is questionable due the lack o
- B8 is required to implement the normative provisions and ultimately produce safe and reliable offshore structure designs This project included identification of metocean data of good quality and sufficient quantity to serve as an adequate statistical sample of data The data was identified acquired and processed After processing into a common format bulk statistics were calculated from the samples These statics included quantile values corresponding to parameter values with a low rate of occurrence
- TOC
-
- Link
-
- P
-
- Link
-
- TOCI
-
- Link
-
- TOCI
-
- Link
-
- TOCI
-
- Link
-
- TOCI
-
- Link
-
- TOCI
-
- Link
-
- TOCI
-
- TOCI_Title
-
- Link
-
- TOCI
-
- Link
-
- Section 1 Meteorological Data
-
- Section 1 Meteorological Data
- General Regional Meteorological Conditions
- Surface wind is the dominant load type of all meteorological conditions affecting offshore structures The highest offshore surface winds can be linked to synoptic and mesoscale weather systems In the BeaufortndashChukchi Seas (BCS) most storm systems do not form locally but move into the region when upper-level winds are favorable and the storm end point depends on the large scale pressure systems acting on it (Francis and Atkinson 2012)
- In the BCS region two storm paths are generally found (Francis and Atkinson 2012) The first path includes North Pacific systems which move into the Bering Sea and transit the Bering Strait and then move up into the Chukchi Sea A secondary storm path runs roughly east to west across the north Alaskan coast These large weather systems (1000s of km in extent) in general depend on baroclinic atmospheric conditions which explain their greater frequency in the non-summer period (Mesquita et al 2010) The
- Synoptic scale pattern
- Synoptic scale patterns (horizontal dimensions 1000 km+) affecting the BCS are characterized by the Beaufort High (BH) and the Aleutian Low (AL) The BH represents anticyclonic high pressure weather patterns that rotate in a clockwise direction The AL represents the impact of cyclonic low pressure systems that rotate in a counter clockwise direction In a cyclone air moves upwards in the center of the pattern bringing stormy wet weather (NSIDC 2016) Traveling cyclones formed in subpolar latitudes in t
- The largest driver of surface winds is due to BCS cyclone activity generated from the AL There has also been an increase in cyclonic activity thus creating greater surface winds speeds From 1948ndash2002 there has been an increase in Arctic cyclone activity (Zhang et al 2004) Zhang et al (2004) found that the number and intensity of cyclones entering the Arctic from the mid-latitudes has increased particularly in summer Also the positive tendencies of mid-latitude cyclone activity correlate with varia
- The cyclones of October 1963 and August 2000 produced the highest winds (25 ms gusts 33 ms) ever recorded in Barrow Alaska which displayed unusual behavior as they tracked eastward from the East Siberian Sea into the Chukchi and Beaufort Seas rather than following a more
-
- The cyclones of October 1963 and August 2000 produced the highest winds (25 ms gusts 33 ms) ever recorded in Barrow Alaska which displayed unusual behavior as they tracked eastward from the East Siberian Sea into the Chukchi and Beaufort Seas rather than following a more
- typical northward track into the Arctic Ocean (Lynch et al (2003) Lynch et al (2003) believed that ice retreat north of Eurasia may have an impact on the increasing cyclonic activity in BCS region
-
- Anticyclonic activity becomes notable during the strengthening of the BH which is generally in summer and autumn For the period of 1979ndash2012 in the BCS region Wu et al (2014) found significant anticyclonic trend among surface wind fields associated with a strengthened BH during summer and autumn but significant cyclonic trends associated with a weakened BH during early midwinter consistent with significant trends in sea level pressure (SLP) gradients between western Arctic Ocean and the adjoining land
- Surface winds
- Stegall and Zhang (2012) observed the wind field climatology changes and extremes from 1979 to 2009 for the BCS regionAlaska North Slope Monthly averaged and 95 percentile wind speeds show a seasonal cycle with a minimum of 2ndash4 ms in May and a maximum up to 9 ms (15 ms in October for 95 percentile) and the prevailing wind direction is northeast at a frequency of 40ndash60 for most of the year The wind speeds showed a clear diurnal cycle over land and sea ice areas during the warm seasons There has al
-
- th
- th
- th
-
- During 1979 to 2009 the climatology also illustrated strong distinctions between coastal and interior locations strong seasonal characteristics and diurnal cycles in wind speed (Baule and Shulski 2014) (Baule and Shulski 2014) found negative trends in wind speed particularly in Alaska Also trends in reanalysis data opposed in situ trends at most locations justifying the need for further in situ studies
- Wind speeds in the BCS region over the period 1970ndash2013 show significant increases over the Bering Sea to the north of Alaska in July and over the central part of BCS in August and September with decreases in the region off the Canadian coasts in August (Wang et al 2015) In the region west of the Canadian coast the climatological mean wind direction has rotated clockwise in July and August with the climatological anticyclonic center being displaced northeastward in August
- Other factors influencing surface winds and atmospheric circulation
- The geography plays an important role in the Beaufort-Chukchi Seas (BCS) The geography in the region is characterized by a seasonally ice-covered ocean along with high mountains inland
- eg Brooks Range in northern Alaska There is also temperature considerations especially in the winter where there is little-to-no sunlight during the winter months which can cause the surface to become extremely cold and often results in temperature inversions The geographic features and temperature influence the weather systems that are generated yielding a complex mesoscale circulation which influences the surface winds in the region
- Cloud cover also influences atmospheric circulation There have been have been changes in the atmospheric circulation thus changes in cloud cover which has a major impact to the surface energy balance (Schweiger 2004) In ocean areas north of 60degN a 5decade decrease in cloud cover during winter (December January February) and up to a 15decade increase in spring (March April May) in cloud cover especially in the Central Arctic was found (Schweiger 2004)
- Mesoscale patterns
- Less common to the BCS region are the mesoscale patterns (horizontal dimensions 5 km to several 100s of km) which are characterized by polar lows (PL) PLs are small intense cyclones that are short-lived which form over the open ocean during cold seasons PLs form when cold Arctic air flows over relatively warm open water A PL ranges in size from around 100 to 500 km in diameter The storms can develop and dissipate rapidly reaching their maximum strength within 12 to 24 hours of formation lasting on
- Moirera (2011) studied a polar low in the BCS region which had a hybrid development and that surface forcings were not important for its formation and intensification The polar low was believed to have been triggered by the interaction of an upper-level potential vorticity anomaly over a low-level baroclinic zone which was favored by the synoptic environment in which the polar low formed Thus there may be other polar lows formed in such a manner
-
- Figure 11 shows the locations at which the data was collected
-
- Figure 11 shows the locations at which the data was collected
- Air Temperature
- Air temperature data from the following sources was plotted checked for integrity and collated
- Each lsquosamplersquo corresponds to measurements collected over a calendar year Years that data was collected ranged from 1999 to 2014 The data was separated by month and histograms were plotted From inspection of the monthly histograms no apparent uniformity or trend was revealed See Figure 12
- While it is possible to fit the data to a probability density function for the purposes of extrapolating extreme values the results would be questionable due to the irregularity of the histogram Such irregularity indicates is does not conform to a standard pdf However the variability in temperature for each month may be assessed qualitatively from Figure 12
- Because of the difficulty in formulating a probability-based approach with these results bulk statistics for the air temperature data have been provided Table 11 summarized the data by month Temperature extremes are characterized with quantile values as well as the maximum and minimum observed As an example for March statistically speaking only 1 of the observed values are colder than -397degC Correspondingly 99 of the temperatures are warmer than 397degC Figure 13 is a plot of the results from T
-
- -
-
- Average monthly freezing thawing degree days were estimated using mean monthly air temperature values and the number of days in each month The results are shown in Figure 14
- No
-
- No
-
- No
-
- No
-
- No
- Month
- Data Pts
- Min
- 1st
- th
- Mean
- Median
- 95th
- 99th
- Max
-
- 1 2
-
- 1 2
- January February
- 103339 94006
- -477 -479
- -422 5 -416
- -385 -38
- -26 -247
- -259 -254
- -142 -101
- -42 -46
- 3 33
-
- 3
-
- 3
- March
- 90604
- -451
- -397
- -367
- -264
- -265
- -153
- -111
- -35
-
- 4
-
- 4
- April
- 75545
- -377
- -296
- -258
- -149
- -149
- -42
- 08
- 81
-
- 5
-
- 5
- May
- 84891
- -285
- -185
- -143
- -53
- -47
- 2
- 39
- 12
-
- 6
-
- 6
- June
- 83153
- -74
- -34
- -18
- 17
- 14
- 66
- 117
- 20
-
- 7
-
- 7
- July
- 89579
- -3
- -04
- 1
- 56
- 52
- 121
- 156
- 233
-
- 8
-
- 8
- August
- 129157
- -3
- -04
- 09
- 51
- 46
- 117
- 154
- 252
-
- 9
-
- 9
- September
- 153307
- -116
- -36
- -21
- 19
- 15
- 69
- 103
- 175
-
- 10
-
- 10
- October
- 114205
- -259
- -171
- -121
- -46
- -38
- 03
- 32
- 113
-
- 11
-
- 11
- November
- 101957
- -388
- -35
- -295
- -159
- -154
- -57
- -31
- 28
-
- 12
-
- 12
- December
- 112462
- -41
- -379
- -341
- -204
- -196
- -76
- -35
- 3
-
- 9
- 10
-
- 10
-
- Wind Speed
- Wind speed data from the following sources was plotted check for viability in this study
- collated and separate by month
-
- collated and separate by month
-
- collated and separate by month
-
- buoyPRDA20 4 samples
-
- buoyPRDA20 4 samples
- buoyPRDA21 5 samples
-
- Cabot
-
- Cabot
- 1 sample
- Cottle Island
- 4 samples
-
- Drew Point
-
- Drew Point
- 13 samples
- Endicott
- 6 samples
-
- McCovey
-
- McCovey
- 1 sample
- Northstar
- 6 samples
-
- Phoenix
-
- Phoenix
- 1 sample
- Prudhoe Bay 3 samples
-
- Each lsquosamplersquo corresponds to measurements collected over one or more calendar years Years that data was collected ranged from 1999 to 2014 The data was separated by month and histograms were plotted See Figure 15 From the histograms it can be seen that a one-sided pdf may be appropriate for the data However some months appear to be more consistent than others from this perspective
- For each month mean and quantile statistics were calculated and are shown in Table 12 Figure
- 16 is a plot of the Table 12 data
- A histogram for the combined data is shown in Figure 17 Based on the corresponding probability plot the associated distribution may be a reasonable approximation of the uncertainty in wind speed Of the pdfs applied to the combined data the Max-Stable Distribution of the following form appeared to fit the data well
- 1
- 1
- x
-
- 1
-
- x
-
- 1 e
-
- Where = location parameter 468454
- = scale parameter 312926
- = shape parameter 00567011
- Table 12 Beaufort monthly wind speed statistics values in ms
- No Month Data Pts Mean Median 95th 99th 9999th Max 1 January 94125 66 57 16 204 267 281 2 February 89927 69 62 152 184 265 28 3 March 93993 65 58 139 175 226 241 4 April 97103 64 59 13 171 225 254 5 May 96962 63 55 144 176 218 234 6 June 94300 68 62 142 181 242 259 7 July 91851 66 62 123 151 19 218 8 August 125908 6 54 125 166 236 274 9 September 153434 72 63 155 192 274 275 10 October 118275 78 68 183 237 318 325 11 November 107413 67
- Mathematically extreme value distributions are the limiting distributions for the minimum or maximum of a very large collection of random observations from the same [arbitrary]
- distribution The values for the distribution parameters shown above were calculated with the combined wind speed data
- A summary of bulk statistics for the combined data is shown in Table XX The table compares the statistical quantile values and those determined with the theoretical pdf fitted to the data
- Table 13 is a summary of bulk statistics for combined wind speed data and values corresponding to Max-Stable Distribution lsquopdf valuesrsquo correspond to Max-Stable Distribution with parameters shown with equation values in ms
- Wind Speed vs Wind Direction
- Wind speed and direction measurement allow examination of the relationship between the two Figure 110 is a plot of the frequency of wind magnitude and direction
- The graphic confirms that the strongest and most frequent winds are from the east Westerly winds are the next most predominant direction Table 14 and Figure 111 further summarize the results and provide quantile values from the data for wind speed versus direction
- Beaufort Wind Speed vs Direction
-
- 002
- frequency
- 360 330
- 001
-
- 001
-
- 001
- 300
-
- TR