Oceanography and Marine Biology: An Annual Review, 2013, 51, 71-192 © Roger N. Hughes, David Hughes, and I. Philip Smith, Editors Taylor & Francis OCEANS AND MARINE RESOURCES IN A CHANGING CLIMATE* JENNIFER HOWARD1,*,†, ELEANORA BABIJ2,†, ROGER GRIFFIS1,†, BRIAN HELMUTH3,†, AMBER HIMES- C O R N E LL4,†, PAUL NIEMIER1,†, MICHAEL ORBACH5,†, LAURA PETES1,†, STEWART ALLEN6, GUILLERMO AUAD7, CAROL AUER1, RUSSELL BEARD8, MARY BOATMAN7, NICHOLAS BOND9, TIMOTHY BOYER1, DAVID BROWN10, PATRICIA CLAY1, KATHERINE CRANE11, SCOTT CROSS12, MICHAEL DALTON4, JORDAN DIAMOND13, ROBERT DIAZ14, QUAY DORTCH15, EMMETT DUFFY14, DEBORAH FAUQUIER1, WILLIAM FISHER16, MICHAEL GRAHAM17, BENJAMIN HALPERN18, LARA HANSEN19, BRYAN HAYUM2, SAMUEL HERRICK20, ANNE HOLLOWED4, DAVID HUTCHINS21, ELIZABETH JEWETT1, DI JIN22, NANCY KNOWLTON23, DAWN KOTOWICZ6, TROND KRISTIANSEN1,24, PETER LITTLE4, CARY LOPEZ1, PHILIP LORING25, RICK LUMPKIN26, AMBER MACE27, KATHRYN MENGERINK13, J. RU MORRISON28, JASON MURRAY29, KARMA NORMAN30, JAMES O’DONNELL31, JAMES OVERLAND4, ROST PARSONS8, NEAL PETTIGREW6, LISA PFEIFFER4, EMILY PIDGEON32, MARK PLUMMER30, JEFFREY POLOVINA33, JOSIE QUINTRELL34, TERESSA ROWLES1, JEFFREY RUNGE34, MICHAEL RUST30, ERIC SANFORD35, UWE SEND36, MERRILL SINGER37, CAMERON SPEIR38, DIANE STANITSKI11, CAROL THORNBER39, CARA WILSON40 & YAN XUE41 1National Oceanic and Atmospheric Administration, 1315 East West Hwy., Silver Spring, MD 20910, USA * E- mail: [email protected] (corresponding author) 2United States Fish and Wildlife Service, 4401 N. Fairfax Dr., Arlington, VA 22203, USA 3Northeastern University, Marine Science Center, Nahant, MA 01908, USA 4National Oceanic and Atmospheric Administration, 7600 Sand Point Way NE, Seattle, WA 98115, USA 5Duke University, 135 Duke Marine Lab Road, Beaufort, NC 28516, USA 6National Oceanic and Atmospheric Administration, 1601 Kapiolani Blvd., Honolulu, HI 96814, USA 7Bureau of Ocean Energy Management, 1849 C Street NW, Washington, DC 20240, USA 8National Oceanic and Atmospheric Administration, National Coastal Data Development Center, Stennis Space Center, MS 39529, USA 9University of Washington, 7600 Sand Point Way NE, Seattle, WA 98115, USA 10National Oceanic and Atmospheric Administration, 819 Taylor St., Fort Worth, TX 76102, USA 11National Oceanic and Atmospheric Administration, 1100 Wayne Ave., Silver Spring, MD 20910, USA * This document is one of the foundational Technical Input Reports for the 2013 National Climate Assessment conducted by the US Global Change Research Program. † Primary authors. 71 JENNIFER HOWARD ET AL. 12National Oceanic and Atmospheric Administration, 219 Ft. Johnson Rd., Charleston, SC 29412, USA 13Environmental Law Institute, 2000 L Street NW, Washington, DC 20036, USA 14Virginia Institute of Marine Science, 1375 Greate Rd., Gloucester Point, VA 23062, USA 15National Oceanic and Atmospheric Administration, 1305 East West Hwy., Silver Spring, MD 20910, USA 16Environmental Protection Agency, National Health and Environment Effects Research Laboratory, Gulf Breeze, FL 32561, USA 17Moss Landing Marine Laboratories, 8272 Moss Landing Rd., Moss Landing, CA 95039, USA 18National Center for Ecological Analysis and Synthesis, 735 State Street, Santa Barbara, CA 93101, USA 19EcoAdapt, P.O. Box 11195, Bainbridge Island, WA 98110, USA 20National Oceanic and Atmospheric Administration, 8604 La Jolla Shores Dr., La Jolla, CA 92037, USA 21University of Southern California, Department of Biological Sciences, Los Angeles, CA 90089, USA 22Woods Hole Oceanographic Institution, Mailstop 41, Woods Hole, MA 02543, USA 23Smithsonian Institute, P.O. Box 37012, MRC 163, Washington, DC 20013, USA 24Institute of Marine Research, P.O. Box 1870 Nordnes, 5817 Bergen, Norway 25University of Alaska, Fairbanks, P.O. Box 755910, Fairbanks, AK 99775, USA 26National Oceanic and Atmospheric Administration, 4301 Rickenbacker Cswy., Miami, FL 33149, USA 27University of California, Davis, One Shields Avenue, Davis, CA 95616, USA 28North East Regional Association of Coastal and Ocean Observing Systems, 570 Ocean Blvd., Rye, NH 03870, USA 29University of South Carolina, 1705 College Street, Columbia, SC 29208, USA 30National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. East, Seattle, WA 98112, USA 31University of Connecticut, 1080 Shennecossett Rd., Groton, CT 06340, USA 32Conservation International, 2011 Crystal Dr., Arlington, VA 22202, USA 33National Oceanic and Atmospheric Administration, 2570 Dole St., Honolulu, HI 96822, USA 34National Federation of Regional Associations for Coastal Observing, 205 Oakledge Rd., Harpswell, ME 04079, USA 34University of Maine, 350 Commercial St., Portland, ME 04101, USA 35University of California, Davis, Bodega Marine Laboratory, Bodega Bay, CA 94923, USA 36Scripps Institution of Oceanography, 9500 Gilman Dr., La Jolla, CA 92093, USA 37University of Connecticut, 354 Mans"eld Rd., Storrs, CT 06269, USA 38National Oceanic and Atmospheric Administration, 110 Shaffer Rd., Santa Cruz, CA 95060, USA 39University of Rhode Island, 120 Flagg Rd., Kingston, RI 02881, USA 40National Oceanic and Atmospheric Administration, 1352 Lighthouse Ave., Paci"c Grove, CA 93950, USA 41National Oceanic and Atmospheric Administration, 5200 Auth Rd., Suitland, MD 20746, USA The United States is an ocean nation—our past, present, and future are inextricably connected to and dependent on oceans and marine resources. Marine ecosystems provide many important services, including jobs, food, transportation routes, recreational opportunities, health bene!ts, climate regulation, and cultural heritage that affect people, communities, and economies across the United States and internationally every day. There is a wealth of information documenting 72 OCEANS AND MARINE RESOURCES IN A CHANGING CLIMATE the strong linkages between the planet’s climate and ocean systems, as well as how changes in the climate system can produce changes in the physical, chemical, and biological characteristics of ocean ecosystems on a variety of spatial and temporal scales. There is relatively little information on how these climate- driven changes in ocean ecosystems may have an impact on ocean services and uses, although it is predicted that ocean- dependent users, communities, and economies will likely become increasingly vulnerable in a changing climate. Based on our current understanding and future projections of the planet’s ocean systems, it is likely that marine ecosystems will con- tinue to be affected by anthropogenic- driven climate change into the future. This review describes how these impacts are set in motion through a suite of changes in ocean physical, chemical, and bio- logical components and processes in US waters and the signi!cant implications of these changes for ocean users and the communities and economies that depend on healthy oceans. US inter national partnerships, management challenges, opportunities, and knowledge gaps are also discussed. Effectively preparing for and responding to climate- driven changes in the ocean will require both limiting future change through reductions of greenhouse gases and adapting to the changes that we can no longer avoid. Introduction Marine ecosystems under US sovereignty, including areas under state and federal jurisdiction, gen- erally extend from the shore to 203 nautical miles seawards. The area under federal jurisdiction spans 3.4 million square nautical miles of ocean—an area referred to as the US Exclusive Economic Zone (EEZ). The United States has the largest EEZ in the world, an area 1.7 times the land area of the continental United States and encompassing 11 different large marine ecosystems (LMEs). In 2004, the ocean- dependent economy generated $138 billion, or 1.2% of US gross domestic product (GDP) (Kildow et al. 2009). US ocean areas are also inherently connected with the nation’s vital coastal counties, which make up only 18% of the US land area but are home to 36% of the US popu- lation and account for over 40% of the national economic output (Kildow et al. 2009). These valuable marine ecosystems and the services they provide are increasingly at risk from a variety of pressures, including climate change and the related issue of ocean acidi!cation (Osgood 2008, Doney et al. 2012). These pressures are affecting ocean physical, chemical, and biological sys- tems, as well as human uses of these systems. Increasing levels of atmospheric carbon dioxide (CO2) are one of the most serious problems because the effects are globally pervasive and irreversible on ecological timescales (National Research Council [NRC] 2011). The present CO2 concentration is the highest on record in at least the last 800,000 years (based on ice core data) (Lüthi et al. 2008). The two primary direct consequences of increased atmospheric CO2 in marine ecosystems are increased ocean temperatures (Bindoff et al. 2007) and higher acidity (Doney et al. 2009). Increased acidity of the ocean is directly related to oceanic absorption of CO2 from the atmosphere. The CO2 reacts with seawater to change the chemical environment of the oceans fundamentally (Feely et al. 2010). However, oceanic absorption of CO2 is dependent on water temperature and pH, and these mechanisms are likely to become less ef!cient as waters warm and pH decreases under future climate scenarios. Increasing temperatures produce a variety of ocean changes, including rising sea level, increased ocean strati!cation, decreased extent of sea ice, and altered patterns of ocean circulation, storms, precipitation, and freshwater