Extreme Rainfall Events Throughout the Himalayas

Writing as background for their study, Nandargi and Dhar (2011) say that "currently there is much discussion regarding the impact of climate change and the vagaries of the weather, in particular extreme weather events," which climate alarmists generally contend will increase in both frequency and severity in response to global warming. And in light of this significant climate of interest, plus the fact that they say "the Himalayas form the main natural water resource of the major river systems of the Indian region," Nandargi and Dhar decided to present "a brief review of the available information and data for extreme rainfall events that were experienced in different sectors of the Himalayas during the last 137 years (1871-2007)," in an attempt to determine "the impact of climate change on the extreme one-day rainfall of the Himalayan region, in the context of rising temperatures."

Working with data obtained from 475 measurement stations, the two Indian researchers proceeded to tabulate the frequency of occurrence of extreme one-day rainfalls within four magnitude categories: 250-300 mm, 300-400 mm, 400-500 mm and greater than 500 mm, focusing on the period of 1951-2007, for which a greater number of stations had more complete records.

With respect to their findings, Nandargi and Dhar write that "to summarize, it may be said that there is an increase in the frequencies of extreme rainfall events from the 1951-1960 decade onwards," but only until "there was a sudden decrease in the frequency of extreme rainfall events in all the four categories in the recent period of 2001-2007, during which time the prevailing monsoon conditions were comparatively weak."

In the concluding words of the paper the two scientists say "it is somewhat baffling as to whether climate change has any impact on extreme rainfall events in the entire Himalayan region, especially in the recent years of the period 2001-2007," demonstrating yet another example of the fact that we still have a lot to learn about what makes the real world tick.