Global Ocean Wind Stress Climatology Based on ECMWF (European Centre for Medium Range Weather Forecasts) Analyses

摘要

Computations of the surface wind stress over the global oceans have been made using surface winds from the European Centre for Medium Range Weather Forecasts for seven years. The drag coefficient is a function of wind speed and atmospheric stability, and the density is computed for each observation. Seven year climatologies of wind stress, wind stress curl and Sverdrup transport are computed and compared with those of other studies. The interannual variability of these quantities over the seven years is presented. Results of the long term and individual monthly means are archived and available at NCAR. It is anticipated that these fields will be useful for driving ocean general circulation models. The wind stress statistics over the southern oceans are believed to be the most reliable available because of the paucity of direct wind observations. The main shortcomings with the current results are in the tropics. The wind stress is shown to vary considerably from year to year and the mean values for the climatology (1980-86) differ significantly from those of previous periods. In the Northern Hemisphere, there is good reason to believe that these changes are mostly real and represent climate variations on interannual and decadal time scales that have major implications for the circulation of the oceans.