On modes of tropical circulation and climate anomalies.

Abstract

Large-scale departure maps of sea level pressure (SLP) and sea surface temperature (SST) are presented for the tropical Atlantic and eastern Pacific Oceans, as obtained by stratification with respect to extreme climatic events in key regions of the tropical Americas. Drought in the Central American-Caribbean region is characterized by an equatorward expansion of the N Atlantic high, a band of anomalously cold water extending across the N Atlantic and a positive SST anomaly in the eastern Pacific. The stratification and principal component analyses are complementary approaches, in that they yield realistic and physically plausible patterns. It is hypothesized that mass exchanges on the scale of the near global tropics dominate the pressure pattern and are related to regional circulation changes and climate anomalies. -from Author