low dissolved oxygen in hood canal hood canal dissolved oxygen program jan newton, ph.d. applied...
Post on 19-Dec-2015
216 views
TRANSCRIPT
Low Dissolved Oxygen in Hood Canal
Hood Canal Dissolved Oxygen Program
Jan Newton, Ph.D.
Applied Physics Laboratory
University of Washington
Tuesday, September 16, 2003
Hood Canal marine life struggling for oxygen
By LISA STIFFLERSEATTLE POST-INTELLIGENCER REPORTER
Yesterday, the state Department of Fish and Wildlife indefinitely closed commercial and recreational fishing throughout the canal for all finfish except salmon and trout, as well as octopus and squid…
U.S. Coastal ‘Dead Zones’ Associated with Human Activity
National attention in 2003
Pew Oceans Commission, 2003
Low oxygen in Hood Canal is not a new observation
- UW: 1950’s observations (Collias et al., 1974 Washington Sea Grant)
- UW-OSU 1970-80’s observations (e.g. Curl and Paulson, 1991, Puget Sound Research Conference Proceedings; Paulson, 1993, Mar. Chem.)
- PSAMP comparison of Ecology (90’s) and UW (50’s) data (Newton et al., 1995, Puget Sound Research Conference Proceedings)
- Ecology’s “Washington State Marine Water Quality during 1998 through 2000” (Newton et al., 2001):
“Similar to our previous assessment (Newton et al., 1998a), four observations from the monitoring data indicate the possibility that DO conditions may be deteriorating in southern Hood Canal, that the spatial extent of low DO may be increasing northwards, and that eutrophication could be one of the processes contributing to this change. Impacts of other human activities (e.g., freshwater diversions) as well as natural cycles must also be fully evaluated.”
• Hypoxia more frequent. • Northward increase in the horizontal extent of hypoxia. • High chlorophyll a concentrations observed when nutrient limitation of phytoplankton
growth expected. • Nutrient-addition experiments show that primary productivity was increased as much as
three-fold (Newton et al., 1995).
http://www.ecy.wa.gov/programs/eap/mar_wat/gradientofconcern.html
Index of concern
What controls oxygen ?
• Seawater density stratification• Seawater flushing/circulation• Organic production and respiration
• Eutrophication/nutrient loading• Organic loading
Start with basics….
WARM
COLD
temperature salinity determine density
FRESH
SALTY
+
less dense
more dense “thermocline” or “pycnocline”
WARM
FRESH
COLD
SALTY
“stratified” “mixed”
Density structure can be two different ways:
Lo nutrient Hi oxygen
Phytoplankton present
Hi nutrient Lo oxygen
No phytoplankton
Organic (primary) production:
Phytoplankton present
No phytoplankton
{ CO2 + H2O C(H2O) + O2 }
sunlight nutrients
“pycnocline”
Respiration
Photosynthesis
WELL-MIXED OXYGEN
HIGH OXYGEN
LOW OXYGEN
“stratified” “mixed”
Oxygen structure can be two different ways:
So why sub-surface low oxygen ?
• Light + nutrients algae• Algae accumulate and eventually settle to
seabed• Organic material decomposition requires oxygen
Lo nutrient Hi oxygen
Hi nutrient Lo oxygen
Which process dominates ?
Phytoplankton present
No phytoplankton
{ CO2 + H2O C(H2O) + O2 }
Photosynthesis
Respiration
P R
. R
O2
So why sub-surface low oxygen ?
• Light + nutrients algae• Algae accumulate and eventually settle to
seabed• Organic material decomposition requires oxygen
• If water is stable, oxygen consumed at depth• If water is mixed/flushed, surface oxygen
replenishes the deep oxygen concentration
Hood Canal attributes
• Strong stratification – distinct layers maintained with different character
(the deep waters with low oxygen don’t get mixed up)
• High productivity – high organic load (that will be respired away during decomposition)
• Slow circulation – long residence time (the bulk of the waters are “old”; lots of respiration has occurred w/o PS or air contact)
Dense (colder, salty) ocean water Intermediate (warming,
freshening) water
Dense (colder, salty) ocean water
Light (warmer, fresher) canal/river water
Hood looks like this:
Dense (cold, salty) ocean water Intermediate (warming,
freshening) water
Dense (cold, salty) ocean water
Light (warmer, fresher) canal/river water
NEW
MEDIUM
OLDEST
NEW
Compare residence times or “age” of waters
Low-ish O2 during upwelling; higher O2 else
Lowest O2, isolated and old water with respiration only
Lower O2, respiration, no air contact
O2 rich, Photosynthesis and air contact
LOW
LOWEST
HIGH
And what about the oxygen ?
Warner et al., 2001
Apr
Jun
Aug
Sep
Oct
Dec
Apr
Jun
Aug
Dec
Nov
Sep
Apr
Jun
Oxygen
In collaboration with UW and PRISM we have learned oxygen dynamics with finer detail.
Hood Hood CanalCanal
•Geology
•Strong Stratification
•High Productivity
•Slow Circulation
Understanding the underlying factors
0
2
4
6
8
10
12
1992 1994 1996 1998 2000 2002 2004
dis
solv
ed o
xyg
en (
mg
/L)
inner Adm iralty
PS Main Bas in
outer Adm iralty
Bellingham B
Budd Inlet
Com m 'm ent B
Dana Passage
Elliott B
Str Georgia
S Hood Canal
N. Hood Canal
Oakland B
West Point
Possess ion S
Pt Townsend
Saratoga P
Sinclair In
Annual mean DO averaged over the bottom half of the water column
S. Hood is different than other Puget Sound locales:
WA Ecology-PSAMP data; Newton (APL-UW) analysis
Lo nutrient Hi oxygen
Phytoplankton present
Hi nutrient Lo oxygen
No phytoplankton
{ CO2 + H2O C(H2O) + O2 }
How do humans affect this??
Lo oxygen can get lower !!!
*sunlight nutrients
Add “new” nutrients from human activity: stormwater, agriculture, fertilized lawns, sewers, septic tanks, animals, etc.
Respiration
Photosynthesis
Lo nutrient Hi oxygen
Phytoplankton present
Hi nutrient Lo oxygen
No phytoplankton
{ CO2 + H2O C(H2O) + O2 }
Add “new” nutrients from human activity: stormwater, agriculture, fertilized lawns, sewers, septic tanks, animals, etc.
How do humans affect this??
Lo oxygen can get lower !!!
*
sunlight nutrients
Respiration
Photosynthesis
Hi carbon Hi oxygen
Hi carbon Lo oxygen
{ CO2 + H2O C(H2O) + O2 }
Add carbon load: carcasses, yard wastes, failing septic tanks, etc.
How do humans affect this??
Lo oxygen can get lower !!!
*
sunlight nutrients
Respiration
Photosynthesis
What controls oxygen ?WHAT SELECTS FOR LOW OXYGEN?
• Stratification STRONG
• Organic production and respiration HIGH
• Flushing/circulation SLOW
• Nutrient or carbon loading OCCURING
What controls oxygen ?WHAT SELECTS FOR LOW OXYGEN?
• Stratification
• Organic production and respiration
• Flushing/circulation
• Nutrient or carbon loading
What controls oxygen ?WHAT SELECTS FOR LOW OXYGEN?
• Stratification STRONG
• Organic production and respiration HIGH
• Flushing/circulation SLOW
• Nutrient or carbon loading OCCURING
Hood Canal attributes:
• Stratification STRONG
• Organic production and respiration HIGH
• Flushing/circulation SLOW
• Nutrient or carbon loading OCCURING
How do we know what we know?
3 primary monitoring efforts
Core station
Rotational station
Washington State Department of Ecology
Marine Waters Monitoring Program
A component of the Puget Sound Ambient Monitoring Program
1. Monthly
2. 4 stations
3. Core since 1975
4. Depth profile
5. Conventional WQ variables
6. Data access via web
7. State funded
University of Washington
Puget Sound Regional Synthesis Model (PRISM)
A University Initiative Fund sponsored program
1. 2x per year
2. 11 stations
3. Since 1998
4. Depth profile
5. Conventional WQ variables
6. Data viewing via web
7. UW funded
HCDOP Citizen Monitoring:
50+ volunteers
Managed by: HCSEG
Direct support from:
UW Ecology PSAT USGS
A volunteer effort
1. Weekly
2. 4-7 stations
3. Since 8-15-03
4. 3 depths
5. Oxygen
6. Data viewing via web
7. Primarily donated, 50+ volunteers
0
2
4
6
8
10
12
19
53
19
54
# m
on
ths
Ecology-PSAMP Monitoring Data
0
2
4
6
8
10
12
19
53
19
54
# m
on
ths
0
2
4
6
8
10
12
19
91
19
92
19
93
19
94
19
95
19
96
19
97
19
98
19
99
20
00
20
01
20
02
20
03
20
04
# m
on
ths
South Hood Canal - Sisters Point – HCB004
UW Historic Data (Collias et al., 1974)
0
2
4
6
8
10
12
19
91
19
92
19
93
19
94
19
95
19
96
19
97
19
98
19
99
20
00
20
01
20
02
20
03
20
04
# m
on
ths
North Hood Canal - Bangor – HCB006/8
Black=no data
White=DO>5 mg/L
Yellow=DO>5 and >3 mg/L
Red=DO<3 mg/L
Newton (APL-UW) analysis
Southern Hood Canal (DB to GB)
Warner: PRISM & UW Collias data
PRISM station transect for inventory:
Southern Hood Canal (DB to GB)
Warner (UW) analysis of PRISM & UW Collias data
Average Dissolved Oxygen Measurements – 1950s - 2004
2003• Low DO was found higher in water column• Another very sunny summer• 50,000 Shiner perch fish kill in June• Very low DO (anoxia) develops• Substantial biota death observed by divers• Another fish closure by WDFW in September• Very large fish kill in October• HCDOP forms: work with ~20 entities to do what
is possible now and draft study plan for future• Developed a website• HCDOP Citizen Monitoring begins
HCDOP Citizen Monitoring Program
Hood Canal Dissolved Oxygen 2003-05 (center station - bottom samples)
0
1
2
3
4
5
6
7
8
9
A S O N D J F M A M J J A S O N D J F
2003 2004
Dis
solv
ed O
xyg
en
(mg
/L o
r p
pm
)
Bangor Hama Potlatch Sister's Point Lynch stress hypoxia
2005
Citizen Monitoring Time-series
Hannafious and Rose (HCSEG) analysis
Sund RockWest Station
0
2
4
6
8
10
12
14
16
18
S O N D J F M A M J J A S O N D J F
2003 2004
Dis
solv
ed O
xyg
en
(mg
/L o
r p
pm
)
surface at 3ft bottom at 20ft bottom 40-60ft bottom 70-90ft
stress hypoxia
Oct. 8th -Large Fish Kill
2005
Sept. 2nd - Small Fish Kill Sept. 25h - Biota Stress / No Kill
Hannafious and Rose (HCSEG) analysis
Most wolfeels were out of their dens, which is uncommon. Many were observed in water depth of less than 20 feet.
This live spot prawn is a very unusual occurrence in shallow waters during the day. Many spot prawn are observed in shallow water during the low dissolved oxygen event and many dead prawns were also observed.
Sightings of fish kills on Hood Canal, October 8-10, 2003
Dead copper rockfish were encountered mostly in waters between 5 and 40 feet in depth.
An astounding 80 copper rockfish were in this dense school in water depths of less than 20 feet.
Blackeyed gobies were found dead in a mat of decomposing material.
WDFW observations W. Palsson
What could cause lower oxygen in Hood Canal ?
• Stronger stratification – distinct layers maintained with different character– Less mixing
• Higher productivity – high organic load– More nutrients, light, stable environment
• Slower circulation – long residence time– Less density driven circulation
**
*
* *Change ocean input:
O2, density
Change river input:
flushing, stratification
Change light availability:
more sun
Change organic biomass/prod’n:
better growing conditions, dumping
Change nutrient availability:
septics, forest, dumping
What is the role of the ocean?
• There is no offshore oxygen time-series data from WA coast
• But do have data from JEMS (Joint Effort to Monitor the Strait) in the Strait of Juan de Fuca
Joint Effort to Monitor the Strait (JEMS)
JEMS Partners:
WA Dept. Ecology
UW PRISM
Friday Harbor Labs
Sea-Doc Society
King County
NOAA
JEMS line
JEMS
fresher, warmer water from Puget Sound and Georgia Basin flowing out
colder, salty water from Pacific Ocean flowing in
North Canada
South U.S.A.
Flow in Strait of Juan de Fuca:
Thomson, 1994
10
6
4
2
8
Oxy
gen
, m
g/L
D - 99 D - 00 D - 02 D - 03D - 01
Is it coming from the ocean input of low oxygen?
JEMS
No evidence found
JEMS data; Newton (UW-APL) analysis
23.0
23.5
24.0
24.5
25.0
25.5
26.0
26.5
27.0
D-98 D-99 D-00 D-01 D-02 D-03 D-04
den
sit
y, kg
/m^
3
JEMS
22
22.2
22.4
22.6
22.8
23
23.2
23.4
23.6
23.8
Mar-97 Mar-98 Mar-99 Mar-00 Mar-01 Mar-02 Mar-03 Mar-04
50 m
Den
sity
at
50 m
2000 20041998 2002
Lower Admiralty Inlet Ecology-PSAMP
140
m
80 m
Den
sity
at
Strait Juan de FucaIncoming ocean water
Deep PS basin water
But what about density?
Newton (UW-APL) analysis
Potlatch Station
Staircase Station
What is role of the river input?
…timing of freshwater input into the lower portion of Hood Canal
USGS river stations
0
200
400
600
800
1000
1200
1400
Jan-41 Oct-54 Jun-68 Feb-82 Oct-95
Mo
nth
ly M
ean
Flo
ws
(ft
3 s-1
)
What is happening to have increased the minimum flow ? >1988 ?
Years with higher Skokomish River discharge to Hood Canal appear to be somewhat correlated with years with lower deep oxygen concentrations.
Potlatch River Station
USGS data; Newton (UW-APL) analysis
0
20
40
60
80
100
120
140
160
180
200
0 2 4 6 8 10 12
Calendar month
Mo
nth
ly m
ean
flo
w (
ft3
s-1)
1940's
1950's
1960's
1970's
1980's
1990's
2000's
See 600% higher flows during summer in 2000's than 1950-80’s
Skokomish River mean monthly flow at Potlatch station
USGS data; Newton (UW-APL) analysis
What about eutrophication?
20 Aug 1998
0
5
10
15
20
25
30
0 5000 10000
P.production (mgC m-3 d-1)
ambient
spike
Nutrient addition causes substantially more primary production
Newton et al., 1995
4625
3225
3412
2900
2360
19832340
2186
1500
~3000
~2000
n=19
n=19
n=5 x 80
n=30
n=8
Primary Production (mg C m-2 d-1)
>1000-2000 >2000-3000 >3000-4000 >4000-5000
Newton et al., 2000
Hood has high production:
32
28
13
10
159
4
1115
% increase in integrated prod’n
<5 >5-15 >15-25 >25-35
Newton et al., 2000
Nutrient sensitivity
Stormwater Impacts
Hydraulic and hydrologic modifications
Individual landscape practices
Agriculture wastes and practices
Aquatic habitat alterations
Commercial forest practices
Changes in aquatic biodiversity
Land-use development standards
Solid waste management
Marine and boat waste
Human sewage
Point sources
Commercial fishing practices
A Look at Factors Contributing to Nutrient Inputs
What we know
• Hood Canal is exhibiting during 2003-04 the lowest oxygen concentrations on record.
• Hood Canal, especially in south, has been showing a gradual increase in severity, persistence, and extent of low oxygen.
• There are likely both human and natural processes involved. Which are most influential needs to be quantified.
Hypotheses on possible causes for the lower oxygen concentrations in Hood Canal:
• Changes in production or input of organic matter, due to naturally better growth conditions such as increased sunlight or other climate factors;
• Changes in production or input of organic matter, due to naturally better growth conditions such as increased nutrient availability;
• Changes in production or input of organic matter, due to human-caused loading of nutrients or organic material;
• Changes in ocean properties, such as seawater density that affects flushing of the Canal’s waters, oxygen concentration, or nutrients in the incoming ocean water;
• Changes in river input or timing from natural causes (e.g., drought) or from human actions (e.g., diversion) that affect both flushing and mixing in the Canal.
• Changes in weather conditions, such as wind direction and speed, which affect the flushing and/or oxygen concentration distribution.
Information need
• What is responsible for the low oxygen and what could fix it ??
– Need QUANTITATIVE modeling that is calibrated and verified with ADEQUATE data to run various scenarios in order to answer this question
HCDOP-IAM Strategy:
• Optimize monitoring: marine & fresh water; biota
• Evaluate nutrient loading to canal; all sources• Better constrain flushing estimates• Evaluate climate & ocean effects on water
properties• Understand biota sensitivities• Use computer modeling to mimic HC and then
run “what-if” scenarios• Evaluate potential corrective actions
HCDOP-IAM Study Development
• Late 2002: Briefed Congressman Norm Dicks on problem and need for study
• 2003: Developed plans:– Phase 1: do now with current resources– Phase 2: scientific study plan developed and
submitted with budget to Dicks
• 2004: Dicks secured $1.4M funds to UW-APL and $350K to USGS
• Early 2005: Scientific study to commence
Hood Canal Dissolved Oxygen ProgramHood Canal Dissolved Oxygen Program
HCDOP
Corrective Actions and Education team
(CAE)
Integrated Assessment and Modeling team
(IAM)
Coordinating Group
Structure:
Hood Canal Dissolved Oxygen ProgramHood Canal Dissolved Oxygen Program
HCDOP
IAM team
UW-APLUSGS
Coordinating Group
Tribes CountiesLocal
GroupsStateHCSEG USACE
Collaborating Partners:
UW Applied Physics Lab
UW
Oceanography
USGS
NOAA Fisheries
USFWS
Navy UWC Keyport
HCSEG
Skokomish
Tribe
LHCWIC
Port Gamble S’Klallam
Tribe
USACE
WA Ecology
WDFW
WA DNR
NWIFC
WA DOH
PSAT
UW-WA SeaGrant
Mason County
Kitsap County
Jefferson County
Mason CD
Kitsap CD
Jefferson CD
HCCC
Battelle
UW-PRISM
Planning Participants:
Hood Canal Dissolved Oxygen ProgramHood Canal Dissolved Oxygen Program
HCDOP-IAM Science Plan
• Program Administration
• Marine Water Monitoring Utilize profiling moorings and nearshore transects to measure circulation and water quality
• Fresh Water Flow & Nutrient Loading Monitor flow and water quality in rivers, streams, groundwater and map associated land use
• Marine Life StudiesAssess DO effect on biota and biota effect on DO
• Modeling and Analysis Develop and verify computer models of marine and terrestrial system, run scenarios and corrective action analysis
• Rapid Response & Diver Program Respond to fish kills and algal blooms, maintain diver observation records
Program Administration
“To be co-managed by UW-APL and HCSEG. Provide resources to support program oversight and administration, coordination of science activities among various partner organizations, and interaction of HCDOP-IAM with other efforts regarding Hood Canal.” *
* text from October 2003 Hood Canal Low Dissolved Oxygen white paper by Newton and Hager, as presented at HCDOP-IAM meeting July 28 2004
Task 1:
Marine Water Monitoring
Utilize profiling moorings and nearshore transects to measure circulation and water quality
“Establish permanent mooring buoys to obtain continuous marine water measurements at 5 locations in Hood Canal, to document oxygen and other water properties with appropriate temporal (including nighttime) and spatial resolution to allow for model operation and for assessing mechanisms of variability.”
Task 2:
Freshwater Flow and LoadingMonitor flow and water quality in rivers, streams, groundwater and map associated land use
“Establish the source, quantity, and timing of nutrient inputs and freshwater flow into Hood Canal including rivers, streams, groundwater, storm drains, septic systems, lawns, and agriculture. Data to be collected by participating groups using Ecology supported protocols and analysis (QAPP development) so that data will support use in potential TMDL integration.”
Task 3:
Marine Life Studies
Assess DO effect on biota and biota effect on DO
“Establish how various fish, shellfish, and other sea life respond to low oxygen concentrations, for both chronic and episodic exposure. Evaluate the historic and future marine life balance, evaluate differences with current marine life and recommend whether these changes may be partially responsible for low oxygen.”
Task 4:
Modeling and AnalysisDevelop and verify computer models of marine and terrestrial system, run scenarios and corrective action analysis
“Develop and verify detailed analytical models that represent the hydrodynamic and bio-chemical processes of the marine and watershed, including nutrient inputs in sufficient detail to identify the processes that define the dissolved oxygen concentrations throughout Hood Canal. Conduct studies with the verified model to establish future levels of dissolved oxygen with various corrective action concepts, as well as climate change, and land development changes. Review the analytical model information and the results of marine life studies and develop potential corrective actions. Study the effect of these actions using the analytical model and verify efficacy.”
Task 5:
Rapid Response and Diver Program
Respond to fish kills and algal blooms, maintain diver observation records
“Expand the diver observation plan and provide for rapid response to fish kills and other events.”
Task 7:
Hood Canal Low Oxygen
• Complex issue• Many contributing factors possible• Scientific understanding critical• Focused, collaborative effort
• Though HC most sensitive, other Puget Sound inlets/bays have sensitivity
• Understanding Hood Canal essential