Ocean Acidification: What It Means To Alaska

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1 Ocean Acidification: What It Means To Alaska Ocean Research and Resources Advisory Panel Alaska Sea Life Center July 27 th, 2010 Jeremy T. Mathis Institute of Marine Science School of Fisheries and Ocean Sciences Outline Too Much CO 2 What is ocean acidification? What do we currently know? What are the impacts on marine organisms? What studies are underway in Alaskan waters? How could it affect Alaskan ecosystems?

2 Atmospheric CO 2 Concentrations year ppm y 1 Data Source: Pieter Tans and Thomas Conway, NOAA/ESRL : 1.3 ppm y : 1.6 ppm y : 1.5 ppm y : 2.0 ppm y : 2.3 ppm y Fossil Fuel Consumption: Top Emitters Carbon (tons x 1000) China USA Russian Fed. Japan India Time Gregg Marland et al., CDIAC; Global Carbon Project 2009

3 The CO 2 Problem It is very likely that [manmade] greenhouse gas increases caused most of the average temperature increase since the mid 20 century IPPC 4th Assessment Report The ocean has taken up 1/3 to 1/2 of all anthropogenic CO 2 emissions. However, since the ocean mixes slowly it is concentrated in the upper 10%. Sabine et al. Science (2004) Creating a More Acidic Ocean

4 What is Ocean Acidification? As more CO 2 dissolves into the ocean, more H + ions are given off. As the concentrations of H + ions increase, the ph of the water decreases. A More Acidic Ocean Under the Business As Usual scenario, ocean acidity will likely increase rapidly over the next 25 years.

5 Ocean Acidification Since the beginning of the industrial age, the ph and CO 2 chemistry of the oceans (ocean acidification) have been changing because of the uptake of anthropogenic CO 2 by the oceans. These Decrease changes in ph in ph 0.1 and over carbonate the last two chemistry centuries may have serious impacts on open ocean and coastal marine ecosystems. 30% increase in acidity; decrease in carbonate ion of about 16% Photo: Missouri Botanical Gardens Corals Calcareous Plankton Carbonate Mineral Saturation Depth Depth at which calcite and aragonite become undersaturated and potentially corrosive to shell building organisms Saturation Depth: The closer to the surface the saturation depth, the more likely organisms will be exposed to undersaturated waters

6 A More Acidic Ocean 200 Glacial X 3X CO 2 CO Calcification rate, mmol m 2 d R 2 = CO 2 level in atmosphere Net Calcification Net Dissolution Carbonate ion concentration Low CO 2 High CO Biosphere 2 Results Langdon & Atkinson, (2005) Coccolithophore (single celled algae)

7 Bivalves (e.g. clams) Oysters on the West Coast Now 5 th year of reproductive failure in Pacific Northwest oyster industry. Larval die offs at Whiskey Creek Shellfish Hatchery (Oregon) clearly from acidification. Deaths follow summer upwelling of corrosive, CO 2 acidified seawater. Growers normally rely on hatchery stock; now gleaning wild oysters to grow out. Whiskey Creek Shellfish Hatchery Photo: Robert Emanuel, Oregon Sea Grant

8 The response of juvenile walleye pollock to projected increases in ocean acidification Hatching success, % mortality, growth rate, and body condition Metabolic enzyme activity in age 1 juveniles Analysis of stress hormones ph levels at 8.05, 7.9, 7.6, and 7.2 Eggs hatched under these conditions The response of juvenile walleye pollock to projected increases in ocean acidification A Panel A B A Panel C C C B B C A Panel B B C D Fernandez, Mathis, Hurst, The response of juvenile walleye pollock (Theragra chalcogramma) to projected increases in ocean acidification. Fisheries Oceanography, In Prep.

9 Potential Impacts on Food Webs Physiological Response of OA

10 Coastal Zones at Risk from OA Alaskan coastal waters are cold and highly productive. Both of these increase the amount of CO2 that is absorbed by the water. Upwelling also bring high CO2 water to the surface More CO2 = More Acidic Seasonal Dynamics in the Northern GOA and PWS Mathis, J.T., Shake, K., Wiengartner, T.J., Juranek, L., Feely, R.L., Carbon Biogeochemistry of the Northern Gulf of Alaska and Prince William Sound Part I: Ocean Acidification and the Seasonal Undersaturation of Aragonite. (Submitted Continental Shelf Research)

11 Aragonite Saturation States on the GOA Shelf RB GAK 1 GAK 8 GAK 1 GAK 13 May 2008 Sept Surface Float GAK 1 GAK 13 GAK 1 SAMI ph Sensor Bechtel pco2 System GAK 13 SAMI ph Sensor SAMI pco2 Sensor GAK 1 Mooring Mathis, J.T., Shake, K., Wiengartner, T.J., Juranek, L., Feely, R.L., Carbon Biogeochemistry of the Northern Gulf of Alaska and Prince William Sound Part I: Ocean Acidification and the Seasonal Undersaturation of Aragonite. (Submitted Continental Shelf Research) Terrestrial Preconditioning of Carbonate Parameters pco 2 ph Spring Summer Winter Striegl et al., 2007 PARTNERS Data These river basins are rich in organic matter, but low in carbonate. In winter, ice cover prohibits out gassing of CO 2, driving down ph. 700 samples were collected for DIC and TA in spring and summer of 2008 across the shelf

12 Distribution of ph in upper 30 m in 2008 Spring Summer ph was lowest in the coastal domain, and increased between spring and summer in response to DIC drawdown due to primary production. Mathis, J.T., Cross, J.N., Bates, N.R., Coupling Primary Production and Terrestrial Runoff to Ocean Acidification and Carbonate Mineral Suppression in the Eastern Bering Sea Journal of Geophysical Research Oceans (Submitted Journal of Geophysical Research). Net Community Production in 2008 Sprin g Sum mer Mathis, J.T., Cross, J.N., Bates, N.R., Lomas, M.L., Moran, S.B., Mordy, C.W., Stabeno, P., (2010). Seasonal Distribution of Dissolved Inorganic Carbon and Net Community Production on the Bering Sea Shelf (Biogeosciences, 7,

13 Carbonate Saturation States in Spring 2008 Mathis, J.T., Cross, J.N., Bates, N.R., Coupling Primary Production and Terrestrial Runoff to Ocean Acidification and Carbonate Mineral Suppression in the Eastern Bering Sea Journal of Geophysical Research Oceans (Submitted Journal of Geophysical Research). Carbonate Saturation States in Summer 2008 Mathis, J.T., Cross, J.N., Bates, N.R., Coupling Primary Production and Terrestrial Runoff to Ocean Acidification and Carbonate Mineral Suppression in the Eastern Bering Sea Journal of Geophysical Research Oceans (Submitted Journal of Geophysical Research).

14 Aragonite (Ω) in Spring 2008 (SL Line) Mathis, J.T., Cross, J.N., Bates, N.R., Coupling Primary Production and Terrestrial Runoff to Ocean Acidification and Carbonate Mineral Suppression in the Eastern Bering Sea Journal of Geophysical Research Oceans (Submitted Journal of Geophysical Research). Aragonite (Ω) Summer 2008 (SL Line) Mathis, J.T., Cross, J.N., Bates, N.R., Coupling Primary Production and Terrestrial Runoff to Ocean Acidification and Carbonate Mineral Suppression in the Eastern Bering Sea Journal of Geophysical Research Oceans (Submitted Journal of Geophysical Research).

15 Aragonite (Ω) in Spring 2008 (MN Line) Mathis, J.T., Cross, J.N., Bates, N.R., Coupling Primary Production and Terrestrial Runoff to Ocean Acidification and Carbonate Mineral Suppression in the Eastern Bering Sea Journal of Geophysical Research Oceans (Submitted Journal of Geophysical Research). Aragonite (Ω) Summer 2008 (MN Line) Mathis, J.T., Cross, J.N., Bates, N.R., Coupling Primary Production and Terrestrial Runoff to Ocean Acidification and Carbonate Mineral Suppression in the Eastern Bering Sea Journal of Geophysical Research Oceans (Submitted Journal of Geophysical Research).

16 Potential Impacts to the Crab Fisheries Mathis, J.T., Foy, R.J., Bates, N. R., Ocean Acidification in the Bering Sea: Potential Impacts to the Crab Fisheries (GRL In Prep.) Potential Impacts to the Crab Fisheries Mathis, J.T., Foy, R.J., Bates, N. R., Ocean Acidification in the Bering Sea: Potential Impacts to the Crab Fisheries (GRL In Prep.)

17 Remineralization and Export of High pco 2 Water The remineralization of exported organic matter in the bottom waters creates a high pco 2 environment that suppresses saturation states. These waters then condition the halocline of the Canada Basin. pco2 (µatm) Ar. Sat (Ω) Bates, N. R., J. T. Mathis, and L. W. Cooper (2009), Ocean acidification and biologically induced seasonality of carbonate mineral saturation states in the western Arctic Ocean, J. Geophys. Res., 114, C11007 PhyCaSS Interaction in the Chukchi Sea Bates, N. R., J. T. Mathis, and L. W. Cooper (2009), Ocean acidification and biologically induced seasonality of carbonate mineral saturation states in the western Arctic Ocean, J. Geophys. Res., 114, C11007

18 Decadal Changes in Surface Aragonite Saturation States Yamamoto-Kawai, 2009 Continuous subsurface and bottom pco 2 and ph OA Mooring Deployments Planned for 2011 Continuous bottom pco 2 and ph Continuous subsurface and bottom pco 2 and ph Seasonal surface pco 2 and ph Continuous subsurface and bottom pco 2 and ph Continuous surface and bottom pco 2 and ph

19 Conclusions Impacts of ocean acidification on marine ecosystems are largely unknown. Calcification in many planktonic organisms is reduced at elevated CO 2, but the response is not uniform. Possible responses of ecosystem are speculative, but could involve changes in species composition and abundances could affect food webs and biogeochemical cycles. Baseline data with sufficient resolution are lacking in some of the most sensitive regions (i.e. coastal Alaska). Future Priorities Climate change legislation unlikely to be taken up during this session of Congress. Increase monitoring of OA in key areas around Alaska UAF has created and OA Research Center Thanks to my staff, students and SFOS colleagues Funding from NSF, NOAA, NPRB, AOOS, and SFOS