Impact of the 1997-98 El Nino event on lightning activity over Indonesia

The 1997-98 El Nino was one of the strongest El Nino Southern Oscillation ( ENSO) events of this century. The major impact of the sea surface temperatu re (SST) change during this El Nino event was the shift in convection activ ity from the western to the central acid eastern Pacific ocean affecting th e response of rain-producing cumulonimbus. As a result, convective rainfall s were suppressed near the Western Pacific regions and the Maritime Contine nt including Indonesia. On the other hand, the lightning activity during th e El Nino period increased in contrast (on the average by 57%), As observed by the Tropical Rainfall Measuring Mission (TRMM) Lightning Imaging Sensor and Precipitation Radar, the convective storms during the El Nino were mor e intense. This was supported by the evidence that the El Nino storms had g reater vertical developments and thicker zones containing ice phase precipi tation.