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[1] Marked differences from global trends in terms of diurnal asymmetry of temperature trends were reported earlier for India, indicating that the warming over India was solely contributed by maximum temperatures. We report substantial recent changes in the nature of trends, using updated data sets up to 2003, with special focus on the last three decades. While all-India mean annual temperature has shown significant warming trend of 0.05°C/10yr during the period 1901 -2003, the recent period 1971 -2003 has seen a relatively accelerated warming of 0.22°C/10yr, which is largely due to unprecedented warming during the last decade. Further, in a major shift, the recent period is marked by rising temperatures during the monsoon season, resulting in a weakened seasonal asymmetry of temperature trends reported earlier. The recent accelerated warming over India is manifest equally in daytime and nighttime temperatures.Citation: Kothawale, D. R., and K. Rupa Kumar (2005), On the recent changes in surface temperature trends over India, Geophys.

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Seasonal and annual trends in surface air temperature over India and 7 homogeneous regions (western Himalaya, northwest, north-central, northeast, east coast, west coast and interior peninsula) were assessed during 3 periods: 1901-2007, 1971-2007 and 1998-2007. Indian annual mean (average of maximum and minimum), maximum and minimum temperatures showed significant warming trends of 0.51, 0.72 and 0.27°C 100 yr , with a much steeper increase in minimum temperature than maximum temperature. In the most recent decade, maximum temperature was significantly higher compared to the long-term (1901-2007) mean, with a stagnated trend during this period, whereas minimum temperature showed an increasing trend, almost equal to that observed during 1971-2007. On a seasonal scale, pronounced warming trends in mean temperature were observed in winter and monsoon seasons, and a significant influence of El Niño Southern Oscillation events on temperature anomalies during certain seasons across India was observed. The composites of maximum and minimum temperatures of El Niño years showed positive anomalies during monsoon, post-monsoon and subsequent year winter and pre-monsoon seasons. However, statistically significant positive anomalies were observed only during monsoon and post-monsoon seasons over large areas of the country. The composite temperature anomalies of La Niña years were almost opposite to El Niño composites: the negative temperature anomalies associated with La Niña events persisted from the current monsoon season to the subsequent year pre-monsoon season.KEY WORDS: India · Temperature trend · Decadal average temperature · Global warming · ENSO Resale or republication not permitted without written consent of the publisher

Abnormalities in the performance of the Indian summer monsoon (June to September) rainfall, which provides 75-90 per cent of annual rainfall, have been studied during the period 1871 to 1984 over different meteorological subdivisions into which the country has been divided. Long homogeneous monsoon rainfall series of 29 subdivisions, prepared on the basis of a constant 306 rain gauges, have been tabulated for the users in view of their great importance. The criterion adopted in identification of droughtlflood over a subdivision is the percentage of rainfall departures from normal, as officially used in the India Meteorological Department.The worst drought years were