HR: 10:25h
AN: OS22B-01 INVITED     [Abstracts]
TI: Long-term Changes in the Climate of the California Current, With Biological Impacts
AU: * Miller, A J
EM: ajmiller@ucsd.edu
AF: Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92093, United States
AU: Kim, H
EM: h15kim@ucsd.edu
AF: Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92093, United States
AU: McGowan, J
EM: jmcgowan@ucsd.edu
AF: Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92093, United States
AU: Di Lorenzo, E
EM: edl@gatech.edu
AF: School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA 30332, United States
AB: The CalCOFI dataset in the southern California Current reveals a significant surface-intensified warming and stratification (buoyancy frequency) change across the 1976-77 climate regime shifts. However, the average depth of the thermocline, defined as the maximum gradient of temperature, did not change significantly across the regime shift. But as the surface heating changed the strength of stratification, it also changed the slope of the nitrate-temperature relation for the mid-depth waters (roughly 30m to 200m). This may have affected the quality of upwelled water and the depth from which it is drawn. These historical changes can be useful in anticipating the potential impact of global warming on the oceanic circulation off the coast of California. For example, an eddy- permitting ocean model forced with wind stresses, heat fluxes and open boundary conditions obtained from a global climate model forced by increased greenhouse gases predicts increased upper-ocean temperatures, and increased stratification along the coast. The vertical structure of the thermal response is similar to recent studies of global warming trends.
DE: 4500 OCEANOGRAPHY: PHYSICAL
DE: 4800 OCEANOGRAPHY: BIOLOGICAL AND CHEMICAL (0460)
SC: Ocean Sciences [OS]
MN: 2007 Joint Assembly