Winter Temperature Trends for Chennai

In the series of understanding long term temperature trends across various cities today we take up Chennai winter temperature trends.  Using the temperature data for the period 1980 to 2016 from the Observatory at Chennai Airport we have tried to infer if there is any learning which we need to take into account.  A couple of days back we did for Bengaluru where a clear indication appeared on possible long term warming of the city in particular to the Winter Months.

In the days to come we will try to provide similar analysis for other major cities of the region time and data permitting.  Unlike the Bengaluru story we will restrict ourselves to only the winter months of Chennai in this post with possibly a separate post for Summer a little later on a more detailed manner.

In what could be a surprise for most Chennaites it appears the night time temperatures during the winter months of January & February is showing a very stable trend.  While we might be seeing lesser nights of extreme dips it appears  the minimum temperature seems to be staying closer to normal for more days during these months possibly indicating a gradual but very slow reduction in the mean minimum temperatures.

But if one were to look at the Day Time Temperature trends there is a clear warming showing over the last decade or so.  Since 1995 the average day time temperatures during the winter months of January& February has not dropped lower than 30°C while to the contrary it has crossed 31°C during 9 out of the 17 years since the turn of the millennium which happened only once in 1998 on the back of a fading strong El Nino.

It is interesting to note that the warmest winter years for Chennai AP just like Bengaluru seems to have happened during fading El Nino years once again indicating there are both Local & Global factors always to these warming trends.