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National Atmospheric Deposition Program 2002 Annual Summary
1985 - 1987 1990 - 1992
1995 - 1997 2000 - 2002
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0.150.10 0.20 0.25 0.30 0.35 0.40 0.45|
Average Ammonium Ion Concentration as NH (mg/L)
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0.50 0.55
4+
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2002 Highlights
In 2002, scientists, students, educators, andothers interested in the National AtmosphericDeposition Program (NADP) logged more than150,000 sessions on the NADP Internet site (seethe back cover for the address). This site hadmore than 52,000 unique visitors, a 23 percentincrease since 2001, and now receives more thana million hits annually. Records show that about60 percent of users study atmospheric depositionor its effects on aquatic and terrestrial eco-systems and cultural resources, and 40 percentuse NADP data for educational purposes. Color-contour pH maps from the NADP NationalTrends Network (NTN) appeared in two newcollege textbooks: Meteorology andEnvironmental Geology.
Federal agencies continued to rely on NADPdata to monitor the nation’s air quality andevaluate policy decisions. For example:
Recently, the U.S. Environmental ProtectionAgency used NTN maps to describe sulfatedeposition decreases since sulfur dioxideemissions reductions began under the cap-and-trade program established in the 1990Clean Air Act Amendments.In its report, Air Quality in the NationalParks (second edition), the National ParkService used NTN sulfate, nitrate, andammonium concentration and deposition datato characterize current air-quality conditionsand trends.
Scientists published more than 80 journalarticles using or citing NADP data. Two journaleditions were of special note:
In March, a special issue of Ambio,“Optimizing Nitrogen Management in Foodand Energy Productions, and EnvironmentalChange,” featured papers from “N2001: The2nd International Nitrogen Conference.” Morethan a third of the papers addressed nitrogendeposition and used or cited NADP data.
In April, Atmospheric Environment featured aspecial section “NADP 2000 - Ten Years Afterthe Clean Air Act Amendments” of ninearticles presented at the 2000 NADP TechnicalCommittee meeting.
The NADP is in its third decade of recordinghigh-quality precipitation chemistry data. Afeature article on “Environmental Monitoring andNational Security: Is There a Connection?” in arecent issue of EM suggested ways that monitor-ing networks, such as the NADP, could assist in anational surveillance system for biological, chemi-cal, or radiological agents spread by terrorists. TheNADP has a well-developed communicationsnetwork and management infrastructure, and hasprevious experience with special efforts tomonitor disasters, such as the Chernobyl nuclearaccident in April 1986.
NADP Past
In 1977, U.S. State Agricultural ExperimentStations (SAES) organized a project, later titledNADP, to measure atmospheric deposition andstudy its effects on the environment. Sites in theNADP precipitation chemistry network begancollecting samples in 1978. The goal was toprovide data on the amounts, temporal trends, andgeographic distributions of acids, nutrients, andbase cations in precipitation. In the early 1980s,the network expanded its coverage to the entirecountry. The National Acid Precipitation Assess-ment Program, established in 1981 to improveunderstanding of the causes and effects of acidicprecipitation, provided funding for much of thisexpansion. Today the NTN has about 250 sites.
[About the cover: Pictured are annual precipitation-weighted mean ammonium concentrations for four3-year averaging periods: 1985-1987, 1990-1992, 1995-1997, and 2000-2002. Map animations of con-centration changes for sulfate, nitrate, and ammoniumfrom 1985 to the present are available athttp://nadp.sws.uiuc.edu/amaps/.]
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AK
01
03
Alaska Hawaii#
Puerto Rico Virgin Islands
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3
ÊÚ
ÊÚ
ÊÚ
ÊÚ
ÊÚ
ÊÚ
ÊÚ
ÊÚÊÚ ÊÚ
ÊÚ
ÊÚ
ÊÚÊÚ
ÊÚ ÊÚÊÚ
ÊÚ
ÊÚ
ÊÚ
Years of operation at NTN sites as of December 31, 2002.
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$ 20
5 - 15
1978 - present
15 - 20
Years of operation
ÊÚ
National Trends Network
The NTN is the only network providing a long-term record of precipitation chemistry across theUnited States. Sites predominantly are locatedaway from urban areas and point sources ofpollution. Each site has a precipitation chemistrycollector and gage. The automated collectorensures that the sample is exposed only duringprecipitation (wet-only-sampling).
Site operators collect samples weekly onTuesday morning. They transfer each samplefrom the collection bucket to a shipping bottle,and send it to the Central Analytical Laboratory(CAL) at the Illinois State Water Survey foranalysis, and data entry, verification, andscreening. All sample containers are cleaned atthe CAL, the sole analytical laboratory since theprogram began. The CAL measures sample volume, conductivity, and the following
concentrations: calcium (Ca2+), magnesium(Mg2+), sodium (Na+), potassium (K+), ammonium(NH4
+), sulfate (SO42-), nitrate (NO3
-), chloride(Cl-), and H+ as pH. The CAL also measuresorthophosphate, but only for quality assurancepurposes as an indicator of sample contamination.
The CAL reviews field and laboratory data forcompleteness and accuracy, and flags samples thathave been mishandled, grossly contaminated, orcompromised by precipitation collector failures.The CAL delivers all data and information to theNADP Program Office, which applies a final setof checks and resolves remaining discrepancies.Data then are made available on the NADPInternet site.
The map below shows NTN sites and their yearsof operation as of December 31, 2002. Twentysites have operated continuously since 1978.
4
N(kg/ha)
1.01.0 - 2.02.0 - 3.03.0 - 4.04.0 - 5.05.0 - 6.06.0 - 7.0> 7.0
Inorganic nitrogen wet deposition from nitrate and ammonium, 2002.
National Atmospheric Deposition Program/National Trends Network
Sites not pictured:Alaska 01 0.4 kg/haAlaska 03 0.6 kg/ha
0.9 kg/haVirgin Islands 01 0.9 kg/haHawaii 99
0.1 kg/haCalifornia 95
NTN Maps
The NTN maps show spatial variability in theannual concentration and wet deposition ofselected acidic ions, nutrients, and base cationson regional and national scales. Only sitesmeeting prescribed data completeness criteriaare included. In 2002, 195 sites met thesecriteria. Black dots mark site locations, andannual concentration or deposition valuesappear next to each site. Concentrations are precipitation-weighted averages. (For anexplanation of the data completeness criteria orhow the precipitation-weighted averages ordeposition fluxes were calculated, see theNADP Internet site.)
Color contours on the NTN maps were createdby using site values to compute an array of regularly spaced grid-point values across thenation. Sites within 500 kilometers (km) of each grid point were used in computations. Color
contours represent the classes of concentrations ordepositions indicated in the legend. (For informa-tion about the algorithm used to compute grid-point values, see the NADP Internet site.)
In addition to the map of inorganic nitrogen wetdeposition, below, concentration and depositionmaps show NH4
+, NO3-, SO4
2-, Ca2+, andlaboratory pH. Also shown is a map of totalprecipitation. Maps of Mg2+, Na+, K+, Cl-, fieldpH, and field H+ deposition are not included butare available from the NADP Internet site.
Explanation of NTN Color Contours: Referto the figure below, which has eight inorganic nitrogen deposition classes or contours. Thelightest green color in the legend represents 3.0 - 4.0 kilograms per hectare (kg/ha).Nitrogen deposition values in the area coveredby this contour are greater than 3.0 kg/ha andless than or equal to 4.0 kg/ha.
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2.4
4.4
4.4
1.6
1.91.3
2.9
3.0
5.6
6.4
1.6
3.7
3.9
0.1
4.1
2.72.8
3.5
6.7
6.7
4.5
0.1
4.7 3.9
6.4
3.6
2.5
3.6
3.11.5
1.0
5.3
4.7
6.1
2.3
0.9
2.2
6.2
5.4
1.3
1.2
4.8
1.1
1.7
1.5
5.8
4.9
4.7
4.6
3.1
2.0
3.4
4.6
6.0
6.1
4.6
5.3
3.7
1.3
3.5
4.4
3.7
5.54.2
3.53.9
0.20.9
1.1
0.3
1.9
1.1
1.01.3
1.7
0.9
2.02.0
1.0
3.7
3.4
3.3
2.6
3.6
3.1
2.7
3.04.6
2.6
6.0
5.9
0.90.4
5.6
4.5
4.8
7.5
4.7 5.7
6.2
5.3
5.1
6.24.8
6.34.9
3.8
3.4
3.4
3.2
3.36.4
5.96.2
9.1
4.43.0
4.52.9
5.77.8
4.3
5.2
1.3
1.5
1.1
1.2
4.7
3.9
3.4
5.74.13.3
3.82.4
5.2
4.6
5.3
1.1
0.5
5.8
9.8
5.111.3
4.26.3
6.0
4.6
4.9
6.26.5
5.5
5.3
4.2
4.2
0.3
0.7 0.41.0
1.7
6.37.6
7.1
5.1
1.8 3.7
3.7
5.94.6
2.0
2.5
2.92.0
3.2
1.0
0.9
3.5
4.7
7.2
6.0
1.8
1.2
6.4
6.6
6.4
7.4
6.7 5.7
5.4
1.1
+4
(mg/L)
5
0.100.10 - 0.150.15 - 0.200.20 - 0.250.25 - 0.300.30 - 0.350.35 - 0.400.40 - 0.450.45 - 0.500.50 - 0.55> 0.55
0.50.5 - 1.01.0 - 1.51.5 - 2.02.0 - 2.52.5 - 3.03.0 - 3.53.5 - 4.04.0 - 4.5> 4.5
(kg/ha)
Ammonium as NH
+4Ammonium as NH
Ammonium ion concentration (top) and wet deposition (bottom), 2002.
National Atmospheric Deposition Program/National Trends Network
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0.79
0.36
0.16
0.14
0.480.31
0.17
0.77
0.44
0.27
0.27
0.08
0.11
0.38
0.29
0.070.07
0.15
0.57
0.60
0.47
0.18 0.21
0.42
0.17
0.64
0.28
0.090.33
0.01
0.26
0.34
0.32
0.42
0.31
0.18
0.53
0.21
0.31
0.33
0.29
0.27
0.33
0.12
0.52
0.20
0.12
0.20
0.15
0.51
0.11
0.26
0.37
0.45
0.25
0.25
0.21
0.26
0.15
0.19
0.17
0.240.20
0.230.28
0.330.40
0.23
0.07
0.15
0.47
0.150.14
0.37
0.39
0.910.38
0.28
0.12
0.09
0.12
0.09
0.10
0.10
0.10
0.200.26
0.14
0.61
0.73
0.330.24
0.40
0.46
0.33
0.30
0.42 0.46
0.32
0.45
0.39
0.480.50
0.280.20
0.20
0.21
0.18
0.18
0.150.42
0.620.49
0.75
0.430.42
0.470.36
0.590.66
0.14
0.17
0.38
0.10
0.19
0.28
0.24
0.13
0.20
0.400.210.11
0.550.75
0.73
0.19
0.26
0.32
0.27
0.42
0.41
0.220.42
0.270.24
0.29
0.18
0.26
0.450.30
0.40
0.45
0.32
0.76
0.10
0.02 0.060.08
0.07
0.340.28
0.32
0.20
0.44 0.92
0.20
0.210.17
0.31
0.21
0.140.24
0.20
0.37
0.69
0.16
0.26
0.29
0.27
0.03
0.23
0.49
0.56
0.48
0.59
0.59 0.49
0.21
0.27
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2.2
2.7
2.3
1.2
1.90.8
1.4
2.4
3.5
3.9
1.0
1.6
1.9
0.1
2.7
1.11.1
2.0
4.6
4.9
2.9
2.1 2.3
4.0
1.9
2.0
2.5
1.41.1
0.4
3.0
3.1
4.6
1.6
0.6
1.1
4.4
2.8
0.8
0.9
3.2
0.6
1.1
0.7
3.8
2.9
2.3
2.2
1.5
1.5
1.7
3.0
3.3
3.5
2.5
2.5
2.1
0.8
2.1
2.0
1.9
3.62.4
2.22.8
0.10.6
0.8
0.2
1.4
0.9
0.50.5
1.0
0.6
1.61.3
0.6
1.5
1.2
1.8
1.2
1.7
1.3
1.2
1.93.2
1.4
4.4
4.4
0.70.3
3.6
3.0
3.2
4.9
3.2 3.8
4.0
3.4
3.3
4.63.6
4.12.4
2.1
1.9
1.7
1.6
1.63.9
3.73.8
7.2
3.42.1
3.42.0
4.66.1
2.3
3.1
1.0
0.8
0.7
0.9
2.7
2.2
1.9
4.72.41.9
3.32.0
4.0
2.2
2.8
0.7
0.4
3.5
5.1
2.45.5
2.23.3
3.4
2.2
3.0
3.93.4
3.2
3.6
2.9
3.6
0.2
0.3 0.20.8
1.0
3.53.8
3.7
2.3
1.4 3.0
2.0
3.42.6
1.4
1.7
1.71.4
2.0
0.6
0.7
1.9
2.9
3.7
3.4
0.6
0.9
4.4
4.9
4.6
5.7
4.8 3.9
2.7
0.8
Sites not pictured:Alaska 01 0.09 mg/LAlaska 03 0.11 mg/L
0.03 mg/LVirgin Islands 01 0.04 mg/LHawaii 99
1.10 mg/LCalifornia 95
Sites not pictured:Alaska 01 0.3 kg/haAlaska 03 0.5 kg/ha
0.6 kg/haVirgin Islands 01 0.3 kg/haHawaii 99
0.1 kg/haCalifornia 95
3-
6
0.600.60 - 0.750.75 - 0.900.90 - 1.051.05 - 1.201.20 - 1.351.35 - 1.501.50 - 1.651.65 - 1.80> 1.80
44 - 66 - 88 - 1010 - 1212 - 1414 - 1616 - 1818 - 20> 20
(kg/ha)
Nitrate as NO
3-Nitrate as NO
(mg/L)
Nitrate ion concentration (top) and wet deposition (bottom), 2002.
National Atmospheric Deposition Program/National Trends Network
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1.1
1.4
0.8
0.3
0.51.2
1.0
1.6
1.6
1.0
0.9
0.5
0.6
0.9
1.0
0.50.5
0.6
1.7
1.5
1.7
1.2 0.9
1.5
0.9
1.3
0.8
0.61.0
0.1
1.1
1.1
0.8
1.3
1.3
1.0
1.4
1.1
1.3
0.9
0.9
1.1
1.3
0.8
1.7
0.8
0.6
1.2
0.8
1.2
0.6
0.9
1.7
1.9
1.2
1.5
0.9
0.9
0.6
1.1
0.9
0.80.9
0.80.7
1.51.3
0.6
0.2
0.4
1.1
0.71.0
1.4
1.6
1.91.4
1.1
0.9
0.8
0.6
0.5
0.6
0.7
0.7
0.70.7
0.7
1.6
1.9
0.80.5
1.3
1.5
1.0
1.0
1.3 1.5
1.1
1.6
1.3
1.21.3
1.01.1
0.9
0.9
0.9
1.0
0.81.6
2.21.9
1.6
1.01.2
1.11.0
1.31.5
0.7
0.7
1.0
0.5
0.6
0.7
1.0
0.6
0.9
0.80.90.5
1.01.5
1.7
1.1
1.3
1.3
0.6
1.7
2.1
1.32.4
1.41.2
1.3
1.1
1.0
1.61.5
1.6
1.3
1.0
1.3
0.4
0.1 0.30.2
0.3
1.51.5
1.6
1.2
1.0 1.8
1.0
0.90.7
0.8
0.6
0.60.8
0.8
1.4
1.5
0.8
0.9
1.5
1.2
0.3
0.6
1.5
1.4
1.3
1.4
1.6 1.6
1.1
0.7
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3
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23
8
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4
11
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< 1
9
89
9
14
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10
14 9
14
10
4
7
93
3
13
10
12
5
2
6
12
14
3
2
10
3
4
4
12
12
13
13
8
4
9
10
15
15
12
15
9
3
8
12
10
1210
88
12
2
1
4
2
34
4
2
35
2
11
11
9
7
10
9
8
79
7
11
11
21
12
10
10
16
10 12
13
12
11
129
1413
9
8
9
9
915
1314
16
86
86
1014
11
12
2
4
2
2
11
10
8
9108
64
9
13
14
3
1
14
26
1431
1117
15
13
11
1417
13
11
9
6
1
2 12
4
1621
19
15
3 6
10
1411
4
5
74
7
2
2
9
11
19
15
6
2
13
13
12
13
13 12
14
2
Sites not pictured:Alaska 01 0.2 mg/LAlaska 03 0.2 mg/L
0.1 mg/LVirgin Islands 01 0.3 mg/LHawaii 99
4.3 mg/LCalifornia 95
Sites not pictured:Alaska 01 1 kg/haAlaska 03 1 kg/ha
2 kg/haVirgin Islands 01 3 kg/haHawaii 99
< 1 kg/haCalifornia 95
-24
(mg/L)
7
0.500.50 - 0.750.75 - 1.001.00 - 1.251.25 - 1.501.50 - 1.751.75 - 2.002.00 - 2.252.25 - 2.50> 2.50
33 - 66 - 99 - 1212 - 1515 - 1818 - 2121 - 2424 - 27> 27
(kg/ha)
Sulfate as SO
-24Sulfate as SO
Sulfate ion concentration (top) and wet deposition (bottom), 2002.
National Atmospheric Deposition Program/National Trends Network
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1.7
1.1
1.7
0.2
0.50.6
0.5
1.1
1.6
1.1
1.0
0.9
1.0
0.6
1.4
0.90.8
1.1
1.5
1.2
1.7
1.7 1.3
1.2
1.3
0.9
0.8
0.81.2
0.2
1.6
0.9
1.0
0.7
0.7
0.5
1.1
1.7
0.9
0.6
1.1
0.5
0.8
0.3
2.0
1.0
0.8
1.6
0.9
1.0
0.8
1.2
1.8
2.7
1.9
1.8
1.4
0.6
0.9
1.1
1.3
1.41.0
1.00.8
0.90.9
0.3
0.1
0.2
0.5
0.30.3
0.6
0.7
0.80.6
0.8
1.1
1.1
0.7
0.7
0.7
1.0
0.9
0.91.2
0.8
1.3
1.7
0.50.4
1.7
1.5
1.5
1.4
1.2 1.8
1.8
1.9
1.8
1.31.1
1.41.4
1.3
1.0
0.9
1.0
1.01.4
2.11.6
1.2
0.80.8
0.80.7
0.81.1
0.8
0.8
0.6
0.2
0.3
0.5
1.3
0.8
1.5
1.11.20.8
0.70.8
1.3
1.1
1.6
0.8
0.3
2.1
2.2
1.32.0
1.81.5
1.4
1.3
1.6
2.02.4
2.2
1.2
1.0
1.0
0.2
0.2 0.10.2
0.2
2.12.0
2.2
1.4
0.6 0.9
1.4
1.40.9
1.0
0.9
0.80.9
1.2
0.8
1.3
1.3
1.5
1.8
1.3
0.2
0.3
1.2
1.3
0.9
1.1
1.4 1.5
1.5
0.4
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< 1
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1313
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20 14
12
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3
8
124
8
19
9
14
3
1
3
9
22
2
2
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2
2
15
15
17
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9
3
13
13
16
20
19
19
14
2
12
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15
2012
98
< 11
1
< 1
2
1
11
2
1
12
2
14
15
11
9
11
13
10
815
8
9
10
1< 1
15
10
15
23
9 15
22
14
15
138
2016
13
9
9
9
1113
1213
12
64
64
610
14
15
1
2
1
2
15
14
15
131414
42
7
13
18
2
< 1
17
27
1326
1421
17
16
18
1727
18
9
9
5
< 1
3 12
3
2227
25
16
2 3
13
2214
4
8
105
11
1
1
15
17
23
16
4
1
10
11
9
11
11 12
19
1
Sites not pictured:Alaska 01 0.2 mg/LAlaska 03 0.3 mg/L
1.1 mg/LVirgin Islands 01 0.9 mg/LHawaii 99
2.3 mg/LCalifornia 95
Sites not pictured:Alaska 01 1 kg/haAlaska 03 1 kg/ha
27 kg/haVirgin Islands 01 8 kg/haHawaii 99
< 1 kg/haCalifornia 95
+2 Ca(mg/L)
Ca(kg/ha)
2+
8
0.100.10 - 0.150.15 - 0.200.20 - 0.250.25 - 0.300.30 - 0.350.35 - 0.40> 0.40
1.001.00 - 1.251.25 - 1.501.50 - 1.751.75 - 2.002.00 - 2.252.25 - 2.50> 2.50
Calcium ion concentration (top) and wet deposition (bottom), 2002.
Sites not pictured:Alaska 01 0.03 mg/LAlaska 03 0.04 mg/L
0.02 mg/LVirgin Islands 01 0.16 mg/L
National Atmospheric Deposition Program/National Trends Network
Hawaii 99
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1.72
0.16
0.08
0.03
0.070.42
0.21
0.53
0.21
0.16
0.47
0.07
0.08
0.16
0.27
0.060.05
0.14
0.27
0.34
0.22
0.08 0.10
0.20
0.05
0.46
0.14
0.070.94
0.03
0.14
0.14
0.13
0.28
0.42
0.29
0.25
0.09
0.34
0.46
0.33
0.29
0.24
0.39
0.35
0.10
0.08
0.07
0.04
0.35
0.05
0.04
0.12
0.23
0.12
0.09
0.10
0.30
0.06
0.05
0.09
0.080.12
0.110.17
0.490.21
0.05
0.02
0.04
0.29
0.450.22
0.37
0.25
0.480.42
0.60
0.10
0.09
0.10
0.06
0.09
0.10
0.07
0.050.06
0.07
0.54
0.61
0.400.16
0.21
0.28
0.19
0.15
0.32 0.22
0.18
0.35
0.22
0.390.45
0.120.12
0.05
0.09
0.06
0.06
0.050.20
0.230.26
0.43
0.180.18
0.210.18
0.260.28
0.07
0.08
0.22
0.05
0.15
0.13
0.06
0.04
0.06
0.040.050.03
0.200.32
0.48
0.06
0.07
0.28
0.14
0.11
0.14
0.080.17
0.090.07
0.08
0.08
0.12
0.210.16
0.20
0.37
0.26
0.38
0.09
0.03 0.040.03
0.03
0.080.10
0.11
0.07
0.16 0.37
0.09
0.080.07
0.58
0.16
0.160.26
0.18
1.06
1.88
0.10
0.06
0.10
0.08
0.02
0.07
0.23
0.28
0.22
0.26
0.38 0.31
0.11
0.41
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4.7
1.2
1.2
0.3
0.31.1
1.7
1.7
1.7
2.4
1.8
1.4
1.5
< 0.0
2.4
0.90.8
1.9
2.2
2.8
1.3
1.0 1.0
1.9
0.5
1.4
1.3
1.13.0
1.1
1.6
1.3
1.9
1.0
0.7
1.8
2.1
1.1
0.8
1.2
3.6
0.7
0.8
2.1
2.6
1.4
1.6
0.8
0.4
1.0
0.8
0.5
1.1
1.7
1.2
0.9
1.0
1.0
0.8
0.6
1.0
1.21.5
1.01.7
0.20.3
0.2
0.1
0.4
0.5
1.70.8
1.0
0.4
0.91.4
1.3
1.2
1.3
1.5
0.9
1.5
1.3
0.8
0.40.8
0.7
3.9
3.6
0.80.2
1.9
1.8
1.9
2.5
2.4 1.8
2.2
2.6
1.9
3.73.2
1.71.4
0.5
0.8
0.6
0.5
0.61.9
1.42.0
4.2
1.40.9
1.51.0
2.02.6
1.2
1.4
0.5
0.4
0.6
0.4
0.7
0.7
0.6
0.50.50.6
1.20.8
2.6
0.7
0.8
0.6
0.2
0.91.7
0.92.2
0.70.9
1.0
1.0
1.3
1.81.8
1.6
3.0
2.4
1.8
0.1
0.4 0.20.3
0.4
0.81.4
1.3
0.8
0.5 1.2
0.9
1.31.1
2.7
1.3
1.91.5
1.7
1.8
2.0
1.2
0.7
1.3
1.1
0.4
0.3
2.1
2.4
2.1
2.6
3.1 2.4
1.4
1.2
2.91 mg/LCalifornia 95
Sites not pictured:Alaska 01 0.1 kg/haAlaska 03 0.2 kg/ha
0.2 kg/haVirgin Islands 01 1.3 kg/haHawaii 99
0.5 kg/haCalifornia 95
Lab H(kg/ha)
+
Lab pH
pH measurements made at the Central Analytical Laboratory, 2002.
5.35.2 - 5.35.1 - 5.25.0 - 5.14.9 - 5.04.8 - 4.94.7 - 4.84.6 - 4.74.5 - 4.64.4 - 4.54.3 - 4.4< 4.3
0.100.10 - 0.150.15 - 0.200.20 - 0.250.25 - 0.300.30 - 0.350.35 - 0.400.40 - 0.450.45 - 0.500.50 - 0.55> 0.55
Hydrogen ion concentration as pH (top) and wet deposition (bottom) from
National Atmospheric Deposition Program/National Trends Network
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6.6
4.8
4.5
5.6
6.05.4
5.1
5.9
4.7
4.9
5.2
4.8
4.8
5.4
5.0
4.84.8
4.8
4.9
5.4
4.7
4.5 4.8
4.9
4.6
5.9
5.1
4.85.8
5.4
4.6
5.0
5.0
5.3
5.5
5.2
5.2
4.5
5.1
5.6
5.2
5.6
5.2
5.3
4.8
4.8
4.8
4.5
4.7
5.3
4.8
4.7
4.5
4.4
4.5
4.4
4.7
5.5
4.8
4.6
4.7
4.74.8
4.95.1
5.45.2
5.4
5.4
5.5
5.8
5.45.1
5.3
5.1
5.65.2
5.5
4.6
4.6
5.0
4.9
4.9
4.8
4.7
4.84.7
4.8
5.5
5.6
5.85.8
4.7
4.9
4.8
4.8
5.1 4.7
4.7
4.8
4.7
5.15.4
4.74.6
4.6
4.7
4.7
4.7
4.74.8
4.64.7
5.7
5.35.2
5.55.3
5.55.3
4.8
4.9
5.5
5.2
5.4
5.5
4.6
4.8
4.6
4.94.64.8
5.95.9
5.6
4.6
4.5
5.1
5.8
4.4
4.4
4.64.4
4.54.5
4.6
4.6
4.6
4.64.4
4.5
5.2
5.2
5.7
5.3
5.3 5.45.4
5.3
4.44.4
4.4
4.5
5.4 5.7
4.6
4.64.8
5.4
5.0
5.05.1
4.9
5.7
6.2
4.6
4.6
4.5
4.6
5.1
5.3
5.0
5.1
5.2
5.3
5.1 4.9
4.6
5.7
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< 0.01 0.01
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< 0.01
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0.19
0.02
0.33
0.31
< 0.01
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0.240.26
0.21
0.10
0.04
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0.41 0.19
0.11
0.31
< 0.01
0.07
0.230.01
0.13
0.31
0.09
0.14
0.02
0.01
0.04
0.06
0.43
0.02
0.01
0.07
0.01
0.02
0.03
0.13
0.23
0.31
0.35
0.19
0.01
0.24
0.22
0.29
0.29
0.33
0.37
0.21
0.01
0.21
0.27
0.23
0.310.19
0.130.07
< 0.010.01
0.01
0.01
0.03
< 0.01
0.010.03
0.01
0.01
< 0.010.02
0.01
0.29
0.33
0.15
0.17
0.20
0.23
0.22
0.150.23
0.14
0.02
0.02
< 0.01< 0.01
0.18
0.09
0.17
0.27
0.06 0.17
0.27
0.12
0.17
0.070.03
0.280.30
0.26
0.17
0.18
0.20
0.210.16
0.160.15
0.02
0.040.03
0.030.03
0.020.04
0.26
0.23
0.01
0.04
0.02
0.01
0.27
0.27
0.26
0.140.260.27
0.01< 0.01
0.01
0.30
0.36
0.02
< 0.01
0.29
0.53
0.290.50
0.280.43
0.31
0.33
0.28
0.230.49
0.28
0.05
0.06
0.01
0.01
0.08 0.020.03
0.07
0.410.54
0.48
0.35
0.01 0.01
0.26
0.400.24
0.02
0.09
0.130.04
0.13
< 0.01
< 0.01
0.27
0.29
0.44
0.30
0.14
0.02
0.09
0.06
0.06
0.05
0.06 0.10
0.36
0.01
Sites not pictured:Alaska 01 5.3Alaska 03 5.1
4.7Virgin Islands 01 4.8Hawaii 99
6.2California 95
Sites not pictured:Alaska 01 0.02 kg/haAlaska 03 0.04 kg/ha
0.54 kg/haVirgin Islands 01 0.13 kg/haHawaii 99
< 0.01 kg/haCalifornia 95
9
Total precipitation, 2002.
Precipitation (cm)
2020 - 4040 - 6060 - 8080 - 100100 - 120120 - 140140 - 160160 - 180180 - 200> 200
Sites not pictured:Alaska 01 37 cmAlaska 03 48 cm
245 cmVirgin Islands 01 85 cmHawaii 99
1 cmCalifornia 95
National Atmospheric Deposition Program/National Trends Network
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27
75
149
92
3925
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32
80
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39
200
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3
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153158
136
80
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117 107
96
112
31
90
15332
313
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93
145
37
18
63
85
130
25
26
110
24
32
55
74
144
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111
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29
159
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32
137
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146123
95100
416
36
32
95
18
3739
27
14
1834
22
125
138
151
137
159
128
116
94125
100
72
60
2113
91
66
99
164
77 81
125
75
84
9771
143119
104
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88
11093
5978
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7951
7356
7793
171
187
25
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39
34
113
170
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118114178
5926
55
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20
14
82125
107133
80138
118
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114
86113
80
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91
48
16
172 4295
138
103139
116
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31 33
98
165159
47
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12357
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17
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Years of operation
10
Years of operation at AIRMoN sitesas of December 31, 2002.
Atmospheric Integrated Research Monitoring Network
The Atmospheric Integrated Research MonitoringNetwork (AIRMoN) joined NADP in 1992. As ofDecember 31, 2002, there were ten AIRMoNsites collecting samples within 24 hours of thestart of precipitation (see map at right). WhileAIRMoN measures the same chemicals as NTN,sampling is daily rather than weekly. These higherresolution samples enhance researchers’ ability toevaluate how emissions affect precipitationchemistry using computer models that simulateatmospheric transport and removal of pollutantson a storm-by-storm basis.
The AIRMoN samples are refrigerated aftercollection and until analysis at the CAL to retardchemical changes. Analyses and data screeningprocedures for AIRMoN and NTN are similar.The NADP Program Office makes the dataavailable on the NADP Internet site.
11
8.66.1 5.9 6.6
5.28.4
6.44.8 4.3 4.8
8.1
8.4 9.2
12.4
10.76.1
5.7
5.3 5.56.6
0
2
4
6
8
10
12
14
16
18
20
1993 1994 1995 1996 1997 1998 1999 2000 2001 2002Year
Sulfu
r Dep
ositi
on (k
g/ha
) Sulfate (Dry) and SulfurDioxide (Dry) as SSulfate (Wet) as S
Winter, spring, summer, and fall (top) and annual (bottom) wet and dry depositionof sulfur at the Bondville AIRMoN-wet and AIRMoN-dry site.
0
1
2
3
4
5
6
W S S F W S S F W S S F W S S F W S S F
Season
Sulfu
r Dep
ositi
on (k
g/ha
) Sulfate (Dry) as SSulfur Dioxide (Dry) as SSulfate (Wet) as S
1998 1999 2000 2001 2002
AIRMoN Data
The bar charts above show wet and dry depositionof sulfur (S) at the Bondville AIRMoN-wet andAIRMoN-dry site in central Illinois. Each bar inthe top chart depicts S deposition in kilograms perhectare (kg/ha) for a meteorological season. The1998 meteorological winter is December 1997through February 1998. Spring is March throughMay, etc. The AIRMoN-wet deposition (blue) isthe product of the seasonal precipitation amountand precipitation-weighted-mean S from sulfate.The AIRMoN-dry deposition is the S depositionfrom aerosol sulfate (dark red) and the Sdeposition from gaseous sulfur dioxide (red).Each bar in the bottom chart depicts the annual
(December - November) S deposition. Numbers onthe bars indicate wet or dry S deposition with nodistinction for aerosol or gaseous dry deposition.
Dry depositions of S from aerosol sulfate andgaseous sulfur dioxide were calculated usingatmospheric concentrations, meteorological data,and information on land use, vegetation, andsurface conditions. Individual measurementprograms use different methodologies, which canresult in large differences in S deposition esti-mates. The National Oceanic and AtmosphericAdministration, Air Resources Laboratory,sponsors the AIRMoN-dry program. For moreinformation, see http://www.arl.noaa.gov/research/projects/airmon_dry.html.
Years of operation at MDN sites as of December 31, 2002.
12
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Mercury Deposition Network
The Mercury Deposition Network (MDN), joinedNADP in 1996. As of December 31, 2002, therewere 73 active MDN sites, including ten sites inCanada (see map, below). All MDN sites collectsamples using a precipitation chemistry collectorespecially modified to preserve mercury andequipped with ultra-clean glassware. The auto-mated collector ensures that a sample is exposedonly during precipitation (wet-only sampling).Precipitation is measured with a recording gage.All samples are analyzed for total mercury and asubset of samples for the more toxic methylmercury at Frontier Geosciences, Inc., Seattle,Washington. Data are reviewed and validated bythe NADP Program Office before they are madeavailable on the NADP Internet site.
MDN Data
The MDN maps on page 13 show the 2002precipitation-weighted average concentrations andwet depositions of total mercury (Hg) in precipita-tion. Colored dots mark MDN sites meetingprescribed data completeness criteria. In 2002, 54
sites met these criteria. The colors representconcentration or deposition classes indicated in thelegend. Concentration and deposition values areprinted next to the colored dots. (For an explana-tion of the data completeness criteria and howprecipitation-weighted averages or depositionswere calculated, see the NADP Internet site.)
The maps also show where the U.S. EnvironmentalProtection Agency has posted fish or wildlife con-sumption advisories. These advisories warn thathigh concentrations of mercury have been found orare suspected in fish or wildlife from certain waterbodies in these areas, and that consumption ofthese fish or wildlife may pose health risks. Forty-three states and 8 Canadian Provinces haveadvisories (see www.epa.gov/ost/fish).
Mercury in fish and wildlife can come from manynatural processes, including precipitation. Theconnection between mercury deposition and mer-cury in fish or wildlife is under study. Researcherscan use MDN data to evaluate the role of mercurydeposition as a source of mercury in aquatic andterrestrial ecosystems.
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Total mercury concentration (top) and wet deposition (bottom), 2002.Mercury advisories are for fish and wildlife consumption, not deposition.
13
MercuryAdvisories
NoneAt least 1 inState/ProvinceStatewideCoastal
MercuryAdvisories
NoneAt least 1 inState/ProvinceStatewideCoastal
44 - 66 - 88 - 1010 - 1212 - 1414 - 1616 - 18> 18
Hg g/m ) 2(
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9.8 9.39.9
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Hg (ng/L)
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9.4
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9.8 14.111.4
17.4
10.3
18.7
18.2
9.910.2
7.8
9.2
9.4
6.2
10.0
6.1
5.64.9
5.7
4.18.0
6.0
7.8
3.6
3.3
5.7
2.1
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4%9%
46%
41%
14
1% 6%
34%59%
Frequency of population density classes.
UrbanSuburbanRuralIsolated
Contiguous United States NADP sites
Recent Developments
Most NTN sites were installed predominantlyaway from pollution sources, such as urban areas,industrial operations, power plants, and animalfeeding operations. The NADP siting criteriaspecify minimum separation distances from theseand other potential sources. More than a third ofthe NTN sites have operated for 20 years or more,and land-use changes have occurred at some sites,such that urban or industrial development hasencroached on these minimum separationdistances. In addition, important new environ-mental issues, requiring long-term wet depositiondata in coastal, urban, and suburban areas, haveemerged. The NADP is addressing these issues bylocating new sites in these areas, even though notall siting criteria could be met.
Recognizing that these changes can affect wetdeposition, the NADP developed a site classifi-cation and characterization scheme that providesdata users with information about potentialinfluences of human activities. This schemecomplements information that the NADP alreadycompiles: site latitude, longitude, elevation, water-shed, and ecoregion. (For a complete descriptionof this scheme, see the NADP Internet site.)
Site Classification
Sites are assigned to one of four classes, based onpopulation density within a 15-km radius:
Urban 400 or more people/km2
Suburban 100 - 399 people/km2
Rural 10 - 99 people/km2
Isolated fewer than 10 people/km2
Population density was based on year 2000 U.S.census data. The pie charts, below, display thefrequency of occurrence of population densityclasses in the contiguous United States and atNADP sites. The map on the back cover shows theclassifications for all NADP sites in the UnitedStates, Puerto Rico, and the Virgin Islands.
Site Characterization
Sites are characterized by four factors related to:(1) population density within 15 km, (2) roaddensity within 5 km, (3) sulfur dioxide emissionsdensity within 25 km, and (4) nitrogen oxideemissions density within 25 km. Each factor rangesfrom 0 to 99, the percentile rank of the density atthe site compared with the distribution of densitiesfor the contiguous United States. The map on page15 shows U.S. sulfur dioxide emissions densities;the plot shows percentile ranks for five sites withnearly 25 years of continuous operations.
0.1
1
10
100
1,000
10,000
100,000
1,000,000
0 20 40 60 80 100
15
MN16(36)
Percentile rank
NY20(50)
GA41(58)
CA88(73)
CO15(93)
Sulfur dioxide emissions densities in the contiguous United States (top) and percentileranks (bottom) of five NTN sites illustrate how site characterization factors are assigned
(see page 14 for explanation.)
Sul
fur d
ioxi
de e
mis
sion
s de
nsity
(tons
/km
)2
S S
S
S
S
< 100100 - 10001000 - 10000> 10000
Sulfur dioxideemissions (tons/km )2
MN16
NY20
GA41
CA88
CO15
NADP Data Report 2003-01
The NADP Program Office is located at the Illinois State Water Survey, an affiliated agency of theUniversity of Illinois and a Division of the Illinois Department of Natural Resources.All NADP data and information, including color contour maps in this publication, are available from the NADP Internet site:
http://nadp.sws.uiuc.eduFor further information, special data requests, or to obtain copies of this publication, contact theNADP Program Office, Illinois State Water Survey, 2204 Griffith Drive, Champaign, IL 61820. Telephone: (217) 333-2213 Fax: (217) 244-0220 e-mail: nadp@sws.uiuc.edu
The NADP is National Research Support Project
Note: When referencing maps or information in this report, please use the citation: National Atmospheric Deposition Program. 2003. National Atmospheric Deposition Program 2002 Annual Summary. NADP Data Report 2003-01. Illinois State Water Survey, Champaign, IL.
- 3: A Long-Term Monitoring Program in Support of Research on the Effects of Atmospheric Chemical Deposition. More than 250 sponsors support the NADP, including private companies and other nongovernmental organizations, universities, local and state government agencies, State Agricultural Experiment Stations, national laboratories, Native American organizations, Canadian government agencies, the National Oceanic and Atmospheric Administration, the Environmental Protection Agency, the Tennessee Valley Authority, the U.S. Geological Survey, the National Park Service, the U.S. Fish & Wildlife Service, the Bureau of Land Management, the U.S. Department of Agriculture - Forest Service, and the U.S. Department of Agriculture - Cooperative State Research, Education, and Extension Service (under agreement no. 2002-39138-11964) . Any findings or conclusions in this publication do not necessarily reflect the views of the U.S. Department of Agriculture or other sponsors.
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top related