Publication Name

Extreme rainfall events – Ganges

Differences in highest rainfall baseline 1961–1990

Percentage

1971–2000

1981–2007

-50 -25 -5 0 5 25 50

Differences in rainfall intensity baseline 1961–1990

Millimetres per day

1971–2000

1981–2007

-5.0 -2.5 -0.5 0 0.5 2.5 5.0

being the hottest month in the upper basin and May the hottest in the lower basin. The coldest month is January across the whole basin. Over the last decades, there has been no significant trend in terms of changes in maximum temperatures, but there has been an increase in minimum temperatures in every season across the Ganges basin, with as much as a 0.7°C increase in winter minimum temperature. Night-time temperatures are also showing an increasing trend. Extreme high temperatures (highest maximum) are generally increasing across the basin. Extreme low temperatures are rising (getting warmer) in most parts of the basin with more severity over the central part of the basin, while in the northern-most part temperatures are decreasing (getting colder).

There are changes in extreme rainfall events and the number of rainy days, but these changes vary across the basin, increasing in some locations and decreasing in others. Rainfall intensity shows a decreasing trend over the western section of the southern part of the basin. Temperature Over the past decades and across the Ganges basin, winters are getting warmer, but summer average temperatures have remained constant. Summer extremes are becoming more intense, while winter extremes are showing mixed trends across the basin. The average maximum temperature across the basin is 30.3°C in summer and 21.1°C in winter. The average minimum temperature across the basin is 21.5°C in summer and 6.4°C in winter. The pre- monsoon season is the hottest in the Ganges basin with an average temperature of 31.4°C, with June

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