COLUMN 3

There is strong scientific consensus that marine ecosystems are threatened by climate change. In California, shoreline and nearshore ecosystems serve critical ecological and economic functions. Shoreline ecosystems include sandy beaches, rocky intertidal zones, mudflats, salt marshes, estuaries, and lagoons. State waters

Corynactus, Point Loma Photo © Edward Andrew Woods

extend three miles offshore and support a variety of ecosystems such as seagrass beds, kelp forests, rocky reefs, and sandy sea floor. As climate changes, many of these habitats and the organisms inhabiting them will be adversely impacted or eliminated due to shifts in ocean temperature, changes in ocean chemistry (e.g. increased sedimentation, decrease in pH), shoreline erosion, and sea level rise. Dunes and beaches will be lost as sea level rises and storm surges become more frequent. Wetland systems will also be lost, and saltwater intrusion into coastal aquifers will increase. Kelp forests, which decline in temperatures above 68° F, may be threatened. Fish stocks already in decline are predicted to be further reduced as a result of climate change impacts. Efforts to preserve and protect marine resources are likely to become more challenging because biological response to climate change, especially in the marine environment, involves a multitude of variables beyond temperature that are difficult to track and address. An increased ability to predict future impacts will be particularly important for conserving marine resources.

For more information:

• View a presentation given on May 23, 2007 at the San Francisco Bay Conservation and Development Commission titled, The Impact of Climate Change on California's Coasts and Oceans: Beyond Sea Level Rise, by Franklin B. Schwing, NOAA Fisheries Service, Environmental Research Division.

• Read the journal article, The impacts of climate change in coastal marine systems. Ecology Letters 9 (2), 228–241
• View video presentations on ocean acidification from Oregon Sea Grant