HR: 14:00h
AN: OS12B-02 INVITED     [PDF]
TI: Recent Changes in Large Scale Ocean Salinity Distributions in the Context of Climate Variability
AU: * Curry, R G
EM: rcurry@whoi.edu
AF: Woods Hole Oceanographic Institution, MS #21, Woods Hole, MA 02543 United States
AB: The oceans serve both as a global reservoir and agent of redistribution for several important constituents of Earth's climate system, among them heat, freshwater, and CO$_{2}$. Whereas these ocean components are themselves freely exchanged with the atmosphere, salt is a component that is not. As a widely measured and approximately conserved property, the distribution of salinity in the ocean can be used to diagnose rates of freshwater transport, local ocean mixing, and surface freshwater fluxes. In the lengthening timeline of the instrumental record we are beginning to identify decadal to multi-decadal changes in ocean salinity distributions that appear to have a global structure. In particular, water masses ventilated in the low latitude oceans, where evaporation rates are strong, have become distinctly more saline and warmer in recent decades, while an opposite freshening has been observed in water masses ventilated at higher latitudes of both hemispheres. Because the tapestry of climate variability is richly colored by the interweaving of many threads, it has not yet been feasible to precisely partition the observed changes into their causal components. Nonetheless, certain aspects of the climate system -- regional modes of wind and precipitation patterns, a melting cryosphere and enhanced hydrologic cycle associated with warming surface temperatures -- stand out as leading candidates and will be discussed in a global ocean context.
DE: 4215 Climate and interannual variability (3309)
DE: 4271 Physical and chemical properties of seawater
DE: 4283 Water masses
DE: 4536 Hydrography
DE: 4572 Upper ocean processes
SC: Ocean Sciences [OS]
MN: 2003 Fall Meeting