OCEAN ACIDIFICATION The Other CO2 Problem Outline Overview ofocean acidification science Results of ocean acidification surveys What are the potential biological impacts? Where do we go from here? Richard A. Feely, Ph.D. NOAA Pacific Marine Environmental Laboratory Northwest Indian Fisheries Commission Workshop August 12, 2010
Atmospheric accumulation 234 Pg C (46%) Land-use change 160 Pg C (31%) Terrestrial sink 147 Pg C (29%) Fossil emission 348 Pg C (69%) Ocean sink 127 Pg C (25%) Cumulative carbon sources and sinks over the last two centuries SINKS SOURCES Ocean CO2 Chemistry Global Carbon Project (2008) Carbon Budget and trends 2007, www.globalcarbonproject.org, 26 September 2008
Rates of increase are important Ocean CO2 Chemistry atmospheric CO2 global temperature Hoegh-Guldberget al. 2007, Science
CO2 emissions (GtC/yr) Atmospheric CO2 concentration (ppm) IPCC TAR Emission Profiles from Pre-Industrial Levels Ocean CO2 Chemistry Turley (2006) Drivers for a change in energy policy
Saturation State [ ] [ ] + - 2 2 Ca CO 3 = W * K phase sp , phase Saturation State Ocean CO2 Chemistry W > = 1 precipitation calcium carbonate calcium carbonate W = = 1 equilibrium W < = 1 dissolution
Field Observations Ocean CO2 Chemistry WOCE/JGOFS/OACES Global CO2 Survey ~72,000 sample locations collected in the 1990s DIC ± 2 µmol kg-1 TA ± 4 µmol kg-1 Sabine et al. (2004)
Observed aragonite & calcite saturation depths Ocean CO2 Chemistry Feely et al. (2004) The aragonite saturation state migrates towards the surface at the rate of 1-2 m yr-1, depending on location.
pH distribution in surface waters from the NCAR CCSM3 model projections using the IPCC A2 CO2 Emission Scenarios Projections pH warm water corals deep water corals Feely, Doney and Cooley, Oceanography (2009)
Natural processes that could accelerate the ocean acidification of coastal waters Projections brings high CO2, low pH, low Ω, low O2 water to surface CoastalUpwelling
NACP West Coast Survey Cruise 11 May – 14 June 2007 Newport Aberdeen UCLA MBARI
Seasonal invasion of corrosive waters on west coast North America
NACP West Coast Survey Cruise 11 May – 14 June 2007 Vertical sections from Line 5 (Pt. St. George, California) .... sample locations Feely et al. (2008) The ‘ocean acidified’ corrosive water was upwelled from depths of 150-200 m onto the shelf and outcropped at the surface near the coast.
North American Carbon Program Continental carbon budgets, dynamics, processes & management surface 120m Aragonite saturation state in west coast waters
Summer 2008 transect: Coast to Hood Canal Lower pH and lower saturation states in subsurface waters of Hood Canal than along the Washington Coast Feely et al. (2010)
Reduced growth, production and life span of adults, juveniles & larvae
Reduced tolerance to other environmental fluctuations
Uncertainties great RESEARCH REQUIRED Changes to ecosystems & their services
Experiments on many scales Biosphere 2 (provided by Mark Eakin) Aquaria & small mesocosms SHARQ Submersible Habitat for Analyzing Reef Quality
Major planktoniccalcifers extant species mineralform generation time Coccolithophores ~ 200 calcite days algae Foraminifera ~ 30 weeks calcite protists Pteropods ~ 32 months to year? aragonite snails
Coccolithopores Single-cell algae manipulation of CO2 system by addition of HCl or NaOH pCO2 280-380 ppmv 780-850 ppmv Emiliania huxleyi Gephyrocapsa oceanica Calcification decreased - 45% - 9 to 18% Riebesell et al.(2000); Zondervan et al.(2001)
Formanifera single-celled protists -4 to -8% decline in calcification at pCO2= 560 ppm -6 to -14% decline in calcification at pCO2= 780 ppm Bijma et al. (2002) Shell mass is positively correlated with [CO32-]
Shelled pteropods planktonic snails Whole shell: Clio pyramidata Arag. rods exposed Prismatic layer (1 µm) peels back Respiratory CO2 forced ΩA <1 Shells of live animals start to dissolve within 48 hours Aperture (~7 µm): advanced dissolution Normal shell: nodissolution Orr et al. (2005)
Potential Economic Impacts 4 $4B primary commercial sales in 2007 fed a $70B industry, adding $35B to GNP Varying regional importance of fishery groups calls for local adaptation Total consequences could be far-reaching for ecosystems and marine-dependent societies 1.5 Uninfluenced Predators Crustaceans (crabs, etc) Bivalves (oysters, etc.) 3 1 Billions of U.S. $ 2 0.5 1 0 0 U.S. NewEngl. Mid-Atl. Gulf Pac. HI AK Cooley & Doney, 2009
Mussels & oysters Mytilusedulis& Crassostreagigas Decrease in calcification rates for the both species Significant with pCO2 increase and [CO32-] decrease At pCO2 740 ppmv: 25% decrease in calcification for mussels 10% decrease in calcification for oysters Gazeau et al., 2007
Bivalve juveniles Hard shell clam Mercenaria 0.3 mm newly settled clams
Massive dissolution within 24 hours in undersaturated water; shell gone within 2 weeks
Dissolution causes mortality in estuaries & coastal habitats
Common in soft bottom habitats
Potential food web impacts Coccolithophores ARCOD@ims.uaf.edu Copepods Barrie Kovish Pacific Salmon V. Fabry Vicki Fabry Pteropods
15% 60% 63% Diet of juvenile salmon Pteropod Impacts of increasing pCO2 on nearly 100% of prey types are unknown Barrie Kovish Food web impacts Vicki Fabry Armstrong et al., 2005
Winners & Losers Sea-grass shoot density epiphytic CaCO3 Differing pH levels in Mediterranean CO2 vents off Ischia Island (pH 8.17 to 6.57) Hall-Spencer et al. Nature (2008)
Ischia CO2 vents Variation in pH & species abundance Hall-Spencer et al. Nature (2008) Live Patella caerulea and Hexaplextrunculus (gastropods) showing severely eroded, pitted shells in areas of minimum pH7.4 Tipping point at around 7.8 or even higher
How do you differentiate between a threshold and new regime?
Different “pH Tipping Points” for different species?
Pacific Northwest oyster emergency Willapa Bay seed crisis
Failure of larval oyster recruitments in recent years
Commercial oyster hatchery failures threatens $100M industry (3000 Jobs)
Low pH “upwelled” waters a possible leading factor in failures
Larval oyster may be “canary in goldmine” for near-shore acidification?
Upwelling favorable winds Winds from S Coastal upwelling linked to high mortality events Higher salinity Lower salinity High mortality High survival High Ωarag Saturation (Ωarag) Low Ωarag Figure courtesy of Alan Barton
NOAA OA Research Implementation Plan Monitor trends Ecosystem responses Model changes & responses Develop adaptation strategies Conduct education and outreach
Importance of Moorings Preliminary results show a clear seasonal trend in pH and a strong correlation with pCO2 Note: pH scale is reversed 2007 – 1st OA mooring in Gulf of Alaska at Papa Station First ocean acidification mooring Gulf of Alaska at Station Papa - 2007 Collaboration and coordination across international, federal and state agencies is vital.
Biological impacts & sensitivity to CO2 perturbations Much of our present knowledge stems from…
Omnibus Land Management Act of 2009 2009 Introduced June & November 2007 Senate Bill passed House Billpassed Federal Ocean Acidification Research and Monitoring Acto of 2009 (H.R. 146) Presidentsigned
Since the beginning of the industrial age surface ocean pH (~0.1), carbonate ion concentrations (~16%), and aragonite and calcite saturation states (~16%) have been decreasing because of the uptake of anthropogenic CO2by the oceans, i.e., ocean acidification. By the end of this century pH could have a further decrease by as much as 0.3-0.4 pH units. Possible responses of ecosystems are speculative but could involve changes in species composition & abundances - could affect food webs, biogeochemical cycles. More research on impacts and vulnerabilities is needed. An observational network for ocean acidification is under development. Modeling studies need to be expanded into coastal regions. Physiological response, mitigation and adaptation studies need to be developed and integrated with the models. Conclusions