climate change and its impacts on pnw...

Acknowledgements: Walt Nelson, Cheryl Brown, & Chris Janousek for assistance with slides

Climate Change and Its Impacts on PNW Estuaries

Henry LeeU.S. EPA

Western Ecology DivisionPacific Coastal Ecology Branch

Newport, Oregon

Many Issues

Many Partners

Multi-agency Climate ResearchPredicting climate change threats to key estuarine

habitats and ecosystem services in the Pacific Northwest

ParticipantsUSGS: Debbie Reusser, Rebecca Loiselle, Meredith Payne, two students (SLAMM, SST, Arctic fish, species at risk)

EPA: Henry Lee, Cheryl Brown, Chris Janousek, Pat Clinton, Melanie Frazier, Dave Young, new post-doc (SLR model, water quality, marshes, SAV, species at risk)

Forest Service: Rebecca Flitcroft (SLAMM & salmon)

USF&W: Roy Lowe (marshes & restoration)

USDA: Brett Dumbauld & Lee McCoy (oysters & SAV)

The Nature Conservancy: Dick Vander Schaaf (native oysters)

NERR/OSU: Steve Rumrill (native oysters, marshes, SAV)

OSU/OCCRI: Phil Mote (downscaled climate predictions)

National Coastal Assessment Surveys (EMAP): 1999-2006 (Walt Nelson)

Classification of PNW Estuaries (Henry Lee & Cheryl Brown)

Impacts of SLR and Precipitation on Estuarine Water Quality (Cheryl Brown)

Development of a SLR Model for SAV the Yaquina Estuary (Henry Lee, Pat Clinton, Cheryl Brown)

Mapping Emergent Marsh Assemblages & Impacts of SLR on Marshes (Chris Janousek)

Near-Coastal Species at Risk (Henry Lee)

Patterns of SST in North Pacific (M. Payne, D. Reusser, H. Lee, & C. Brown)

Past and Ongoing Climate Related Research by EPA

www.epa.gov/wed/pages/publications/authored.htm




Development of a SLR Model for SAV the Yaquina Estuary (Henry Lee, Pat Clinton, Cheryl Brown)








Impacts of Sea Level Rise (SLR) & Precipitation on Estuarine Water Quality (Cheryl Brown)

Development of a SLR Model for SAV in the Yaquina Estuary (Henry Lee, Pat Clinton, Cheryl Brown)













SIXTH WAVE OF SIXTH WAVE OF EXTINCTIONEXTINCTION









Patterns of near-coastal SST in North Pacific (M. Payne, D. Reusser, H. Lee, & C. Brown)

Inventory of 62 Oregon Estuaries as Defined by the National Wetland Inventory (NWI) and Their Watersheds

by the National Land-Cover Database (NLCD)

Characteristics of PNW Estuaries Affecting Their Vulnerability to Climate

Change & Types of Ecosystem Services

Impacted

Most of the 103 PNW estuaries are small.

Most PNW estuaries have relatively large intertidal areas and relatively small areas of emergent marshes.

Num

ber o

f est

uarie

s

14 16 18 20 22 24 260

10

20

30

40

Rogue River EstuaryOregon

Tillamook EstuaryOregon

RiverDominated

OceanDominated

Ocean vs. River Influence= Area Normalized Flow =

Netarts EstuaryOregon

Volume rainfall on watershed (m3)

Estuary area (km2)Ln ( )

Seasonal and Spatial Salinity Patterns in PNW

Estuaries• Plots show the median salinity with

distance along each estuary with the 25th and 75th percentiles.

• Netarts lagoonal nature is illustrated by the minimal variation in salinity both in space and with seasons.

• Difference between marine- vs. riverine-dominated estuaries is illustrated by the large difference in how far salt is transported into Yaquina compared to the Coquille.

• Use hydrodynamic models to project how spatial and seasonal salinity patterns will change by estuary type in response to SLR and changes in precipitation.

During the Growing Season, the Lower Portions of PNW Estuaries are Dominated by Advected Ocean Nutrients

While Only the Upper Portions are Dominated by Nutrients Associated with River Flow

Yaquina Estuary

Demarcation Oceanv. River Dominance

Most of the native Zostera marina occurs in the Ocean Dominated segment

Emergent marshes showsame pattern?

Target EstuariesFor New Climate Research

*Coquille: Highly river-dominated (VNFI = 143)

*Yaquina: Tide-dominated (VNFI = 42)

Coos: Tide-dominated (VNFI = 14)

Willapa: Tide-dominated (VNFI = 6)

Netarts: Bar built (VNFI = 8)

* = High priority estuaries for hydrodynamic modeling

VNFI = Volume normalized freshwater inflow = Annual volume of precipitation falling on watershed divided by

volume of estuary (Lee and Brown, 2009).

High Priority Impact: Sea level rise and coastal habitats

Both models and measurements indicate that sea level is rising. Both natural and constructed features in the coastal zone of the Pacific Northwest will be affected.

Sea level rise and coastal habitats

(=27 cm per century)

High Marsh

Road

LowMarsh

Tide Flat

Zosteramarina

Sea level rise and coastal habitatsMarsh may migrate landward unless constrained by topography or development.

Community shifts may occur (for example shifting from high to low marsh).

Loss of deeper SAV may be compensated by expansion onto the inundated flats.

Rise in sea level will change the spatial & temporal salinity regime.

Low Marsh

Sea Level Affecting Marshes Model (SLAMM)A Generalized Model to Predict Effects of

Sea Level Rise on Wetlands

SLAMM utilizes existing NWI classifications as the basis of its predictions of SLR effects on wetlands.

Depending upon the habitat, NWI classes may be aggregated into coarser resolution habitats.

SLAMM has a salinity module for salt-wedge estuaries that is not appropriate for most PNW estuaries.

SLAMM does not predict effects on submerged aquatic vegetation (SAV).

SLAMM is open source so it can be modified.

More on the SLAMM modeling effort by Rebecca Loiselle on Tuesday

Sea level rise and coastal habitatsPredictions from SLAMM

Losses for 0.69 m rise by 2100include:-25% of tidal fresh marsh-31% of tidal swamp-32% of brackish marsh-63% of tidal flats

For Willapa, Columbia, & Tillamook:

Local tectonic & ATM. values in OR & N. CA

SLR projections intarget estuaries

SLAMM Model

BATHTUB Model

Loss of tidal marshes by NWI class

Loss of seagrass,

oyster beds, & tidal marsh

Compare preditions & management utility

SLR Projections for Central WA Coast

NRC

Incorporate better regional estimates for default parameters (e.g., sediment accumulation).

Develop more realistic salinity models for PNW estuaries.

Modify SLAMM to incorporate higher resolution emergent marsh assemblage distributions.

Develop SLR model for SAV and other intertidal habitats.

Generate add-on modules for SLAMM (EPA/USGS)?

Generation of SLR Projections for PNW Estuaries and Prediction of Effects on SAV, Marshes, & Oysters

Bathymetry in Yaquina, Tillamook, & Alsea

Depth Distribution of Z. marina in Yaquina

Predicting Change in Area of Zostera marina –

“Bathtub” Assumptions (estuary configuration fixed)

Seagrass Percent Change with Different Levels of Sea Level RiseAssuming Fixed Estuary Area ("Bathtub" Assumptions)

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

0 m + 0.25m + 0.50m + 0.75m + 1.00mSea level Rise

Perc

ent C

hang

e

TillamookYaquinaAlsea

Under these assumptions, area of SAVincreases with small to moderate levelsof SLR.

Geographically Weighted Regression ToolMarine Geospatial Ecology Tools - ArcRStats

Rule set based on inequalities

Niche models – CART, MARS , Logistic Regression

Great Minds Don’t Always Think AlikeNext Steps in Developing SLR Model for SAV

Dinner

Don’t forget Debbie’s b

Next Steps in Developing a Generalized SLR Model for SAV

Intertidal vs. Subtial Area - Tide Dominated

y = 1.7197x - 0.3064R2 = 0.9861

0

50

100

150

200

250

300

0 20 40 60 80 100 120 140 160Subtidal Area

Inte

rtid

al A

rea

Develop Niche Models for SAV

GIS-based vs. regression based

Incorporate changes in salinity

Incorporate estuary classes

Predict Changes in Estuarine Geomorphology

Consistent geomorphology by estuary class?

Sediment accumulation rates

Shoreline modification (“squeeze”)

Can We Generate Higher Resolution and/or More Accurate Predictions of the Effects on Emergent Marshes Then the Current Version of SLAMM?

Map specific emergent marsh assemblages in the Yaquina Estuary and incorporate into SLAMM or other model.

Develop realistic salinity models for classes of PNW estuaries incorporating both advection of ocean water and changes in river flow.

Quantify/model the actual tidal and seasonal salinity patterns for emergent marshes.

Using marsh data from Yaquina and other estuaries, develop niche models that convert existing NWI classes into specific wetland assemblages in PNW estuaries.

0

5

10

15

20

25

30

5/7/2009 5/12/2009 5/17/2009 5/22/2009 5/27/2009 6/1/2009

Salin

ity, p

su

-1.5

-1

-0.5

0

0.5

1

1.5

2

2.5

3

3.5

Wat

er L

evel

, m (M

LLW

Criteser's MarshSalinityChannel Salinity

Water Level

Elevation When MarshInundated

Salinity Patterns in the Channel May Not be Representative of Marsh Exposure

Marsh only inundatedon the highest high tides.

Deploying a Suite of Salinity Arrays in Yaquina, Coquille, and Netarts to Measure Actual Exposure in a

Suite of Marsh Assemblages

+ 2.25 m

+ 3.00 m (MLLW)

+ 2.50 m

+ 2.75 m

CONCLUSIONS/DIRECTIONS

Integrating several approaches – field work, data mining, hydrologic modeling, niche modeling, climate modeling, etc.

Requires a number of different skills and partners.

Expect different levels and types of impacts in different types of estuary classes.

Predicting effects across a suite of PNW estuaries requires a balance between generality versus site-specific details.

QUESTIONS?

Integration of downscaledclimate and SLR projections with hydrodynamic models to project changes in habitat type and environmental conditions.

Input projected changes into niche and habitat suitability models for SAV, marshes, oysters, salmon habitat, and burrowing shrimp

Generation of Climate Projections for PNW and

Coupling with Habitat and Niche Models

Niche Modeling to Evaluate Effects of Climate Change on Key Estuarine Species

Sea water, stream, air temperature increases

A1B scenario

Sea level rise varies along the Oregon coast

Source: Komar & Allen (2000)


Location Relative Sea Level Rise (mm/y)

Crescent City -0.54Port Orford -0.31Charleston 0.29South Beach 1.22Garibaldi 0.88Astoria 0.04

More recent study by Burgette et al. (2009)


Potential Effects on Coastal SystemsSea level rise/ coastal floodingWave heights increaseTemperature increase in ocean,

streams & airHydrological cycle modificationsChange in coastal upwellingOcean acidificationOcean dead zones??

Biological community changesRange shiftsPrimary productivity shiftsSpread of non-indigenous Species

Global Climate Change and the PNW

Modified from Harley et al. (2006)

Sea levelrise

IntensifiedUpwelling?

Human activities Increased greenhouseGas concentrations

IncreasedUV

Changes inriver inflow

Increasedair & streamtemperatures

Intensified atmosphericPressure gradients

Increase storm frequency

IncreasedCO2

Decreased pH

Increasedwater temperature

Coastal Upwelling:Influence on Water Quality In Estuaries

•Influences N, P, chlorophyll a, pH and dissolved oxygen levels in PNW estuaries.

•Results in high background nutrient loading.

•May obscure anthropogenic signatures.

Comparison among estuaries in the distribution of the non-native Japanese eelgrass, Zostera japonica among salinity zones among Oregon estuaries.

Distribution of eelgrass Zostera marinawith depth in Tillamook Estuary

Most of the seagrass occurs within a narrow depth range (-1 to +1 m).

As with a lawn, seagrass needs light to thrive.

Limited light penetration in the water column typically limits the depth to which seagrasses can grow.

Seagrass distributions would be sensitive to small changes in water depth resulting from sea level rise.

pH scale

What effects will this have on the estuary?

Research is only starting on this issue, and much is unknown.

The range of pH over latitude and depth in the Pacific spans ~ 7.5 – 8.2.

The span of pH in Tillamook Bay during EMAP sampling was 6.7 – 8.2.

The range of current natural variability in estuaries is much higher than for the open ocean.

Source: Kleypas et al. , 2006.

Ocean Acidification

pH of Sea Water Entering PNW Estuaries is Directly Influenced by Upwelling

5 /1 /2 0 0 4 6 /1 /2 0 0 4 7 /1 /2 0 0 4 8 /1 /2 0 0 4 9 /1 /2 0 0 4 1 0 /1 /2 0 0 4

7 .2

7 .4

7 .6

7 .8

8 .0

8 .2

-3 0

-2 0

-1 0

0

1 0

pH

D a te

p H

Integrated Wind Stress, m

2 s-1

W in d S tre s s

Ocean Acidification

Source: WED, USEPA

climate change and its impacts on pnw...

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