Climate Change Chart of Chennai, India

Overview of climate changes

Changes in rainfall

Mean daily rainfall increased on average across calendar months, with a difference of +0.72 mm/day compared with the earlier period. This is an unweighted mean of monthly means, not a change in annual rainfall totals, and does not imply an increase in every month. The largest monthly increase was in November, with a difference of +2.86 mm/day, while the largest decrease was in March, with a difference of -1.12 mm/day. These contrasting monthly differences show why the overall mean should not be read as a uniform shift across the calendar.

Changes in sunshine duration

Mean daily sunshine duration decreased on average across calendar months, with a difference of -0.13 hours/day. This unweighted summary of monthly means describes an aggregate rather than every month, and the largest monthly decrease was in November, with a difference of -0.49 hours/day. In contrast, September recorded the largest monthly increase, at +0.11 hours/day, so the monthly differences were not all in the same direction.

Temperature changes

Monthly mean temperatures were higher on average across calendar months in the more recent reference period, with a difference of +0.38 °C; this unweighted mean summarizes the monthly means and is not a measure of daytime maximum temperatures. The largest monthly increase was in October, at +0.69 °C, illustrating that the size of the difference varied by month.