On the Interannual Variability of the Eastern Pacific Warm Pool
Abstract
The variability of the Eastern Pacific Warm Pool (EPWP) is studied analyzing observations from the Modular Ocean Data Assimilation System, results from the HYbrid Coordinate Ocean Model (HYCOM), and sea surface height anomaly data. Results indicate that the EPWP strengthens and weakens, but remains throughout the year. The monthly variability of the EPWP is primarily forced by the surface heat fluxes (SHF), which generate the EPWP's May (January) maximum (minimum) coverage of ~4,000,000 (~30,000) km2 and the July mid-summer minimum of ~2,300,000 km2. In addition to the SHF the interannual variability of the EPWP is influenced by the coastal-warm-water advected poleward by the Costa Rica Coastal Current and interannual coastally-trapped- waves (CTWs). During its poleward propagation the interannual CTWs generate westward propagating long Rossby waves that advect the coastal-warm-water offshore, contributing to the westward strengthening of the EPWP. Furthermore, it is shown that the dimensions of the EPWP increase (decrease) during El Niño (La Niña) years.
- Publication:
-
AGU Spring Meeting Abstracts
- Pub Date:
- May 2007
- Bibcode:
- 2007AGUSM.A32B..03Z
- Keywords:
-
- 4200 OCEANOGRAPHY: GENERAL;
- 4215 Climate and interannual variability (1616;
- 1635;
- 3305;
- 3309;
- 4513)