Polar Satellite Precipitation Data Center

What's new in PSPDC?

What a difference in the rain pattern change in Pacific and Indian oceans (August 1997 vs. 1998). We are now in the La Nina cycle.

Difference of a La Nina August and an El Nino August

We have received and processed SSM/I data up to December 1998 for both 5° by 5° and 2.5° by 2.5° resolution monthly products.

The 1997 El Nino Southern Oscillation (ENSO) event is one of the major ENSO events in recent years. Higher than normal sea surface temperature occurs throughout the tropical Pacific in the summer of 1997. These SST anomalies are among the largest observed in the past 50 years. During the 1997 ENSO event (Total Rain, August 1997), our monthly means show a clear northward shift of both the South Pacific Convergence Zone (SPCZ) and the Atlantic Inter-tropical Convergence Zone (ITCZ), while the Pacific ITCZ expands and intensifies. These shifts and intensifications are clearly depicted in the rainfall anomaly map (See figure below) which shows the departure of the August 1997 mean from the ten year climatology. Drier-than-normal conditions occur around the Indonesia-Australia region while wetter-than-normal conditions appear in the northern Pacific.

Aug 1997 Precipitation Anomaly

Last Update: September 14, 2015
Research Scientist: Dr. Si Gao, AOES/GMU
Please send questions and comments to: Prof. Long S. Chiu