The Role of SST in the East Pacific Warm Pool in the Interannual Variability of Central American Rainfall Journal Article uri icon

Overview

abstract

  • Satellite- and gauge-based precipitation and sea surface temperature (SST) are analyzed to understand the role of SST in the east Pacific warm pool (EPWP) in the interannual variability of Central American rainfall. It is shown that, during the rainy season following the mature phase of an El Niño event, an anomalously warm EPWP can cause a rapid enhancement of the eastern Pacific intertropical convergence zone (EP ITCZ), which directly leads to a positive rainfall anomaly over Central America. Moreover, the timing and amplitude of the SST-enhanced EP ITCZ depends on the persistence of the El Niño event. The longer the equatorial SST anomaly persists, the longer the EPWP is subject to anomalous shortwave heating, and thus the stronger (and later) the subsequent SST enhancement of the EP ITCZ. The implications for regional climate monitoring and predictability are explored; potential predictability of seasonal rainfall is demonstrated 4 months in advance using an SST-based index designed to capture the essence of the above-mentioned mechanism.

publication date

  • May 1, 2009

Full Author List

  • Karnauskas KB; Busalacchi AJ

Other Profiles

Additional Document Info

start page

  • 2605

end page

  • 2623

volume

  • 22

issue

  • 10