Climate Variability in Ocean Surface Turbulent Fluxes

Principal Investigator: Dr. Mark A. Bourassa, Center for Ocean-Atmospheric Prediction Studies
Project Summary

Florida State University (FSU) produces monthly in-situ fields of surface winds (the ‘FSU Winds’) for the tropical Pacific and Indian Oceans. We are developing a much higher quality product for air-sea interaction (fluxes of heat, moisture and momentum) that also uses satellite data. Our long-term monthly fields are available in time for monthly updated El Nino – Southern Oscillation (ENSO) forecasts, within eight days after the end of the month. The flux-related variables are useful for forcing ocean models, testing the realism of atmosphere and ocean prediction models that link the ocean and the atmosphere (which is important for longer weather forecasts and seasonal to interannual forecasts for variability like ENSO), and for understanding some aspects of climate related variability.

The FSU activity is motivated by a need to better understand interactions between the ocean and atmosphere on daily to interdecadal time scales, and on spatial scales from ocean basin wide phenomena like ENSO to small scale processes related to sea surface temperature fronts and surface current gradients. Air-sea exchanges (fluxes) are sensitive indicators of changes regional climate and weather patterns, with links to floods and droughts and East Coast storm intensity and storm tracks. On smaller spatial and temporal scales they can be related to the storm surge and tropical storm intensity. On longer temporal scales, several well-known natural climate variations have been identified as having direct impact on the U.S. economy and its citizens. For example, changes in the pattern of winds over the South Eastern United States change the amount of rain that falls in each region, and modifies the strength of the land sea breeze (which accounts for 40% of the precipitation in North Florida). Improved predictions of ENSO phase and associated impact on regional weather patterns could be extremely useful to the agricultural community.