Transcript National Health and Environmental Effects Research Laboratory Office of Research and Development

Office of Research and Development
National Health and Environmental Effects
Research Laboratory
Gulf of Mexico Hypoxia Monitoring & Modeling
Water Quality Issues in
the Gulf of Mexico
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Reduce coastal nutrient loads
Reduce hypoxia in northern Gulf
Improve water quality
Restore wetlands
Preserve habitats
Sources:
Gulf Alliance, draft report
NCCR2, 2005
Hypoxia Action Plan, 2001
Office of Water Needs
Office of Wetlands, Oceans
& Watersheds
MS River/Gulf of Mexico
Watershed Nutrient Task Force
2001 Hypoxia Action called for
reassessment in 5 years – assess
progress towards goals and revise if
needed
SAB will conduct assessment of Gulf
hypoxia science (beginning in 2006) - SAB
will require information update (GED lead
for Hypoxia Science Symposium)
MS River Basin and Gulf receiving water
focus for EcoProtection MYP revision
Office of Science & Technology
National Nutrient Criteria
Nutrient criteria recommendations for
freshwater systems by ecoregion released in
2001 - States are working to revise FW criteria
OST required to release estuarine nutrient
criteria recommendations by 2007
OST required to release nutrient criteria
recommendations for wetlands and coastal
marine waters by ???
Gulf Hypoxia Monitoring and Modeling
Western Ecology Division
Newport, Oregon
Peter M. Eldridge
MED Field Station
Grosse Ile, Michigan
Russell G. Kreis Jr.
Office of Water
Washington DC
Gulf of Mexico Program Office
Stennis, Mississippi
Gulf Ecology Division
Gulf Breeze, Florida
Richard M. Greene
Gulf Hypoxia Monitoring and Modeling
Goal:
Develop consensus modeling framework targeting Gulf hypoxia
o to reduce uncertainty and enhance credibility
of model estimates of nutrient load reductions
required to meet Action Plan goals
o provide defensible options to guide
restoration and decision-making
CENR National Hypoxia
Assessment Report (1999)
o Primary obstacle to reducing model uncertainties … is lack of a
sufficiently comprehensive database
o Existing database not designed to quantify load-response
relationships – new monitoring approaches needed
o Comprehensive monitoring programs alone will not be sufficient
for developing, calibrating and validating quantitative WQ
models – relevant and targeted research needed
o Future modeling should include linkages of WQ/Eutro and
hydrodynamics, expansion of spatial domain, and refinement of
temporal and spatial resolution – new integrated, multimedia
modeling constructs needed
ORD Objectives
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Establish an integrated multimedia, mathematical modeling
framework that incorporates monitoring, condition assessment,
diagnosis, and research
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Support the framework with a statistically-based, seasonal
field monitoring design and targeted research
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Integrate physical, chemical, biological components with
external and internal nutrient loads
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Establish stressor-response relationships for nutrient loads &
concentrations, Chl a, and DO
•
Develop predictive capability to forecast the benefits of risk
reduction options and the time to realize the benefits
•
Examine stressor-response relationships using forecasting to
provide bases for biologically-based, nutrient criteria for
ambient nutrients, Chl a, and DO
•
Provide managers with defensible methods, tools, and options
to aid and guide the environmental decision-making process
ORD Gulf Hypoxia Modeling Framework
Meteorological
data
Surface
Wave
Model
Hydrodynamic
Model
Wave direction,
height, period
Mass
Balance
Sediment
Transport &
Diagenesis Model
Advective/
Dispersive
Transport
Water
Quality
Model
Constituent
Mass
loadings
Atmospheric
Transport
Model
Computational
Transport
Deposition
Fluxes
Eutrophication
Model
Dissolved
Oxygen Model
(water/sediment)
Framework Models
Model Components
Partners
Atmospheric
CMAQ, CTM,
MM5
ORD/NERL
Hydrodynamic/
Meteorological
IAS NCOM
USN, NRL
Sediment
transport, fate,
and diagenesis
IPX-MT and
CE-QUAL-ICM hybrid
ORD/NHEERL
Water Quality/
Eutrophication/
WASP and
Dissolved Oxygen CE-QUAL-ICM hybrid
ORD/NHEERL
U.S. EPA-ORD/NERL
Establish a defensible nutrient loading target necessary to
reduce the areal extent of hypoxic bottom waters in the Gulf
Develop eco-forecasting capabilities to evaluate nutrient
management strategies and timelines to achieve results
Conceptual Relationship Between
Maximum Hypoxic Zone Size and
Load Reduction
Hypoxia Recovery Scenarios Under Gradual
Nutrient Reductions and Hydrologic
Variability
Hypoxic Area (103 km2)
30
No Change
-20% by 2015
-50% by 2015
20
10
0
2000
2005
2010
2015
Gulf Hypoxia Monitoring Surveys
Characterize the spatial and temporal variability in oceanographic state and process
variables, including resolution of the seaward and down-plume boundary conditions
of the model domain
Quantify key processes influencing hypoxia to improve predictive models
Develop geo-referenced database to support model development
Gulf Hypoxia Monitoring Surveys
Station Sampling Summary
CTD CTD+Water Benthic
17
19
0
Dec 2–15
2002
29
36
6
March 17–31 2003
26
25
7
June 9–23
2003
28
42
9
Nov 5–19
2003
0
22
4
April 2–7
2004
24
42
10
March 21-31 2005
Sept 26 – Oct 9, 2005 30.5
Surveys Completed
Map shows transect stations
and depth contours
30
29.5
29
28.5
28
27.5
-94.5
-94
-93.5
-93
-92.5
-92
-91.5
-91
-90.5
-90
-89.5
-89
-88.5
Gulf Hypoxia Monitoring
Data – discrete waters samples
collected at minimum of 2 and
maximum of 6 depths depending on
water column structure and depth
Parameter
Dissolved Inorganic –
nitrate, nitrite, phosphate,
ammonium, silicate
Particulate C, N, P
Total Dissolved N, P
Total N, P
Dissolved organic carbon
Total Suspended solids
Biogenic silica
Chlorophyll a
PAR, secchi depth, attenuation
Dissolved oxygen
T, S, turbidity, transmissivity
Phytoplankton taxonomy
Grain size, benthic taxonomy
Total organic matter/organic C
Bulk density, porosity, % water
Primary productivity (14C & FRRF)
Bacterial productivity (3H-Leucine)
Respiration rates
Sediment oxygen demand
Sulfate reduction rates
Benthic nutrient flux
Water Sediment
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Water column stratification
and Hypoxic Region
Bottom Dissolved Oxygen (mg/l)
LA Shelf / Gulf of Mexico -- 3/22 - 3/31/2005
30° N
June 9 – 19, 2003
10
30° N
8
6
29° N
29° N
4
2
D kg/m3
28° N
93° W
28° N
0
92° W
91° W
93° W
90° W
Surface Chlorophyll a
and Hypoxic Region
10
June 9 – 19, 2003
89° W
µg/L
28° N
20
16
7
12
8
29
4
4
0
3
-4
2
-8
1
0
90° W
30
8
5
91° W
90° W
9
6
29° N
92° W
91° W
Relative Chlorophyll-a Fluorescence
LA Shelf / Gulf of Mexico -- 3/22 - 3/31/2005
30° N
93° W
92° W
28
+++++ Ship Track
93
92
91
90
89
Resolving Seaward Boundary Conditions
Salinity distributions along transect D showing oceanic conditions seaward
0
20
June 2003
40
Depth (m)
60
80
100
0
120
20
140
0
March 2003
40
20
40
60
80
100
120
140
0
10
20
30
40
50
60
70
80
90
100
Transect Distance (km)
60
80
100
Continuous Surface Mapping Array MS River to Fourchon
29.4
29.2
Stop
Start
Cruise track
29
-90.5
-90.4
-90.3
-90.2
-90.1
Surface salinity and PO43-
30
25
-90
-89.9
-89.8
-89.7
-89.6
-89.5
-89.4
-89.3
-89.2
-89.1
-89
2.0
Mixing zone
3-
10
1
3-
1.0
15
PO4 (M)
Salinity
20
PO4 (M)
1.5
0.5
0
5
0
5
0.0
Not baseline corrected
0
09:00:00
11:00:00
13:00:00
Time
15:00:00
10
15
Salinity
20
25
Project Timelines
FY ‘02
FY ‘03
FY ‘04
FY ‘05
FY ‘06
FY ‘07
FY ‘08
Planning
Field Monitoring
Sample/Data Analysis
Database Development
Model Development
& Application
APM
Cruise
Report
APM
WQ
Trends
APM
Dbase