Nino3.4 warming trend and extreme rainfall events with flood and drought years over India

An analysis of historical sea surface temperatures provides evidence for global warming since 1900, in line with land-based analyses of global temperature trends, and also shows that over the same period, the eastern equatorial Pacific cooled and the zonal sea surface temperature gradient strengthened. Recent theoretical studies have predicted such a pattern as a response of the coupled ocean-atmosphere system to an exogenous heating of the tropical atmosphere. The authors examine the relationships between Central Pacific Ocean (Nino3.4) sea surface temperature (SST) and the interannual rainfall variability of Indian summer monsoon during 1975 to 2004 (30 years). Nino3.4 warming trend has a strong relation with extreme rainfall events with flood and drought years over India. It has been found that for normal/excess years a strong negative anomaly and for bad/below normal years a strong positive SST anomaly over Nino3.4 region.