Impacts of Ocean Acidification on Water Chemistry and Larval Oysters in Puget Sound

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 Laboratory 2: University of Washington, School of Oceanography 3: NOAA, Pacific Marine Environmental Laboratory 4: Pacific Shellfish Institute 5: Taylor Shellfish 6: Puget Sound Restoration Fund 7: Washington Department of Ecology

[CO2] 50 300 pH 8.2 40 240 2− CO3 2− 8.1 30 180 μmol kg−1 pH 8.0 20 120 CO2(aq) 7.9 10 60 0 0 7.8 1800 1900 2000 2100 Year Wolf-Gladrow et al. (1999) Ocean acidification (OA) 2000 30% acidity Diffusion of increased atmospheric CO2 into marine waters, results in increase of aqueous CO2 (pCO2), decrease in pH and CO32-, and thus decreased saturation state of carbonate materials (Ω aragonite and calcite). 16% [CO3 ] 2100 100−150%  50% [CO3 ] 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 Ocean CO2 Chemistry Feely et al. (2004) The aragonite saturation horizon (Ω = 1) migrates towards the surface at the rate of 1-2 m yr-1, depending on location. Feely (NOAA)

U.S. Pacific Coast Feely et al. (2008)

Is OA affecting oyster survival?

Upwelling favorable winds Winds from S Coastalupwelling Higher salinity Lower salinity High mortality High survival - Linked to high mortality events High Ωarag Saturation (Ωarag) Low Ωarag Figure courtesy of Alan Barton, in press

CO2 CO2 Processes that lead to hypoxia or high CO2 also yield low pH, [CO32-], and Ω values CO2 + H2O CH2O + O2 production CH2O + O2 CO2 + H2Orespiration CO2 Production−Respiration Cycle Feely (NOAA)

1. UW PRISM cruises in Puget Sound, Washington: UW, NOAA, Ecology Feely et al. (2010)

Feely et al. (2010)

Question: How much of the corrosive conditions in Hood Canal result from ocean acidification? Ocean acidification (DICΔOA) = DICAI(avg 2008) − DICAI(avg PI) * PI** Ocean acidification accounts for 24% and 49% of corrosive conditions in summer and winter, respectively. * 2008 ** PI = Pre-industrial AI = Admiralty Inlet • OA accounts for 17 μmol kg-1 higher average CO2 at Admiralty Inlet in 2008 relative to pre-industrial times. 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. Respiration (DICΔR) = DICHC(deep) − DICAI(avg) * * • Respiration accounts for 54 and 18 μmol kg-1 CO2 in summer and winter, respectively. If humans increase deep water respiration by adding carbon or nitrogen loads, this will increase corrosiveness. Feely et al. (2010)

2. OA monitoring in coastal WA and Puget Sound UW, NOAA, OSU UW NANOOS network of autonomous observing buoys UW NOAA Real-time data at: www.nanoos.org UW OSU

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 WA coast Gulf AK Hood Canal Hawaii Courtesy C. Sabine, NOAA PMEL

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.

3. OA monitoring in coastal WA and Puget Sound UW, NOAA, PSI, Taylor, Baywater, PCSGA, PSRF, Ecology Ocean Acidification Monitoring Project funded by the Puget Sound Partnership Two-year study to examine whether or not changing water conditions are affecting shellfish populations Index Sites where shellfish monitored: Dabob Bay: Deep, N-S fetch, stratified Totten Inlet: Shallow, protected, mixed

Dabob Bay Summer 2009 Importance of wind-induced local upwelling Alin (NOAA)

Totten Inlet Summer 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

Impacts of Ocean Acidification on Water Chemistry and Larval Oysters in Puget Sound

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