1. Ocean acidification in Puget Sound: Recent observations on water chemistry and implications for larval oyster success Jan Newton 1,2, Simone Alin 3, Richard Feely 3, Chris Sabine 3, Al Devol 2, Andrew Suhrbier 4, Dan Cheney 4, Benoit Eudeline 5, Joth Davis 5, Brian Allen 6, Betsy Peabody 6, and Christopher Krembs 7 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

2. Ocean acidification (OA) Diffusion of increased atmospheric CO 2 into marine waters, results in increase of aqueous CO 2 (pCO 2 ), decrease in pH and CO 3 2-, and thus decreased saturation state of carbonate materials (Ω aragonite and calcite). Wolf-Gladrow et al. (1999) 2− [CO 3 ][CO 2 ]  100−150%  50% 2100 8.2 8.1 8.0 7.9 7.8 1800190020002100 50 40 30 20 10 0 300 240 180 120 60 0 pH μmol kg −1 Year pH CO 2(aq) CO 3 2−  30% acidity  16% [CO 3 ] 2000 2−

3. 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

4. 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 CO 2 Chemistry Feely et al. (2004) Feely (NOAA)

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

6. Is OA affecting oyster survival?

7. Coastal upwelling - Linked to high mortality events Figure courtesy of Alan Barton, in press Upwelling favorable winds Higher salinity High mortality Low Ω arag Winds from S Lower salinity High survival High Ω arag Saturation (Ω arag )

8. CO 2 Production−Respiration Cycle CO 2 + H 2 O  CH 2 O + O 2 production CH 2 O + O 2  CO 2 + H 2 O respiration Processes that lead to hypoxia or high CO 2 also yield low pH, [CO 3 2- ], and Ω values Feely (NOAA)

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

11. Question: How much of the corrosive conditions in Hood Canal result from ocean acidification? ** Respiration (DIC ΔR ) = DIC HC(deep) − DIC AI(avg) Respiration accounts for 54 and 18 μmol kg -1 CO 2 in summer and winter, respectively. OA accounts for 17 μmol kg -1 higher average CO 2 at Admiralty Inlet in 2008 relative to pre-industrial times. * * Ocean acidification (DIC ΔOA ) = DIC AI(avg 2008) − DIC AI(avg PI) PI** 2008 ** PI = Pre-industrialAI = Admiralty Inlet Ocean acidification accounts for 24% and 49% of corrosive conditions in summer and winter, respectively. Under 2xCO 2 conditions (atmo. CO 2 = 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.

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

13. 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

14. Twanoh, S. Hood Canal

17. 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.

18. 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 Sound UW, NOAA, PSI, Taylor, Baywater, PCSGA, PSRF, Ecology Two-year study to examine whether or not changing water conditions are affecting shellfish populations

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

20. Totten Inlet Summer 2010 Importance of benthic respiration? Alin (NOAA)

21. Both upwelling and respiration processes are major contributors to the high pCO 2 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.

22. 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