Ocean acidification in Puget Sound: Recent observations on water chemistry and implications for

larval oyster success Jan Newton1,2, Simone Alin3, Richard Feely3, Chris Sabine3, Al Devol2, Andrew Suhrbier4,

Dan Cheney4, Benoit Eudeline5, Joth Davis5, Brian Allen6, Betsy Peabody6, and Christopher Krembs7  

1:  University of Washington, Applied Physics Laboratory2:  University of Washington, School of Oceanography3:  NOAA, Pacific Marine Environmental Laboratory

4:  Pacific Shellfish Institute5:  Taylor Shellfish

6:  Puget Sound Restoration Fund7:  Washington Department of Ecology

Ocean acidification (OA)Diffusion of increased atmospheric CO2 into marine waters, results in increase of aqueous CO2 (pCO2), decrease in pH and CO3

2-, and thus decreased saturation state of carbonate materials (Ω aragonite and calcite).

Wolf-Gladrow et al. (1999)

2−[CO3 ][CO2]

100−150% 50%

2100

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CO32−

30% acidity16% [CO3 ]

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2−

OA in Puget Sound ?• Most of our OA measurements come from the open ocean• Pacific Coast estuaries susceptible to effects from OA: 

– Deep Pacific Ocean waters are oldest (respiration)– Upwelling happens seasonally along west coast of U.S. – Estuaries have more carbon loading naturally, as well as loads from humans

• Estuaries host valuable economic and ecological resources• What are we learning locally re OA in Puget Sound?

– Puget Sound cruises (UW PRISM) documented OA status: • Demonstrable effect of anthropogenic OA in Puget Sound

– Buoys currently measuring OA variables:  • Temporal variation is high, implies complex dynamics in estuaries

– Studies with oyster growers on OA and larvae:  • Connection with biology; possible different mechanisms within Puget Sound

 

Observed aragonite & calcite saturation depths

The aragonite saturation horizon (Ω = 1) migrates towards the surface at the rate of 1-2 m yr-1, depending on location.

 Ocean CO2 Chemistry 

Feely et al. (2004)

Feely (NOAA)

U.S. Pacific Coast

Feely  et al. (2008)

Is OA affecting oyster survival?

Coastalupwelling - Linked to highmortality events

Figure courtesy of Alan Barton, in press

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High Ωarag

Saturation (Ωarag)

CO2 CO2

CO2

Production−Respiration Cycle

CO2 + H2O CH2O + O2

production

CH2O + O2 CO2 + H2O

respiration

Processes that lead to hypoxia or high CO2 also yield low pH, [CO3

2-], and Ω values

Feely (NOAA)

1. UW PRISM cruises in Puget Sound, Washington:UW, NOAA, Ecology

Feely et al. (2010)

Feely et al. (2010)

Feely et al. (2010)

Question: How much of the corrosive conditions in Hood Canal result from ocean acidification?

* *

Respiration (DICΔR) = DICHC(deep) − DICAI(avg)

• Respiration accounts for 54 and 18 μmol kg-1 CO2 in summer and winter, respectively.

• OA accounts for 17 μmol kg-1 higher average CO2 at Admiralty Inlet in 2008 relative to pre-industrial times.

**

Ocean acidification (DICΔOA) =DICAI(avg 2008) − DICAI(avg PI)PI**

2008 ** PI = Pre-industrial AI = Admiralty InletOcean acidification accounts for 24% and 49% of corrosive conditions in summer and winter, respectively.

Under 2xCO2 conditions (atmo. CO2 = 560 ppmv), the contribution of OA to corrosive conditions would rise to

approx. 50% and 80% in summer and winter, respectively.

If humans increase deep water respiration by adding carbon or nitrogen loads, this will increase corrosiveness.

NANOOS network of autonomous observing buoys

2. OA monitoring in coastal WA and Puget SoundUW, NOAA, OSU

UW

UW

UW

NOAA

OSU

Real-time data at:

www.nanoos.org

Variability is much larger in coastal waters than the open ocean, then there are estuaries

Variability is much larger in coastal waters than the open ocean, then there are estuaries

Courtesy C. Sabine, NOAA PMEL

Gulf AK

Hawaii

WA coast

Hood Canal

Twanoh, S. Hood Canal

Twanoh, S. Hood Canal

Twanoh, S. Hood Canal

   Estuaries have a complex story OA to tell, but correlations with forcing functions, e.g., river input, sunlight, winds, stratification/mixing, tides, etc. are allowing interpretation of variation and, moreover, may lead to forecasting of risk.

Index Sites where shellfish monitored:

Dabob Bay: Deep, N-S fetch, stratified

Totten Inlet:Shallow, protected, mixed

Ocean Acidification Monitoring Project funded by the Puget Sound Partnership

3. OA monitoring in coastal WA and Puget SoundUW, NOAA, PSI, Taylor, Baywater, PCSGA, PSRF, Ecology

Two-year study to examine whether or not changing water conditions are affecting shellfish populations 

Dabob BaySummer 2009 Importance of wind-induced local upwelling

Alin (NOAA)

Totten InletSummer 2010 Importance of benthic respiration?

Alin (NOAA)

Both upwelling and respiration processes are major contributors to the high pCO2  and low pH, undersaturated bottom waters that are highly vulnerable to further acidification in the future, there is need to better understand status, trends, and linkages with biological responses in Puget Sound.

Summary: OA in Puget Sound ?

• OA affects Puget Sound• Additional respiration matters • OA variable spatially and temporally but interpretable 

• Further monitoring of waters and biology needed to understand implications for organisms & food web