Odisha has grown warmer over the years. This is a proven reality that during the last 114-year period (1901-2015). The trend observed for the variance in the annual mean temperature of the State reveals a rise in the range of 1 -1.5 degree Celsius.
More so, it seems owing to a mix of the rising annual mean temperature coupled with the persistent decline in the Standard Precipitation Index during the year 2015-16 which measures the wet/arid status of a landscape together have made Odisha hotter this summer.
A look at the data available with IMD Pune throws more light on the rainfall and the growing aridity in Odisha in 2015-16. When a high of around six to seven districts of Odisha figured among the 99 moderately dry districts in the country during the last monsoon period, by the end of April 2016 the number swelled to around 11 and the number of severely dry districts rose to around eight (parts of Sundargarh, Deogarh, Keonjhar, Rayagada, Kandhamal, Nayagarh, Khordha and Cuttack) from a mere one in 2015. The remaining districts were declared as mildly dry.
Interestingly, the districts that figured as moderately dry during 2015 evolved into severely drier ones by April 2016 and they are the ones that are experiencing acute water crisis now, which sheds poor light on the State’s disaster monitoring and mitigation capabilities.
Significantly, the rainfall variance data with the IMD for the period March to mid-May 2016 puts in perspective on why Odisha was hotter than its neighbouring States this summer. It reveals Odisha has recorded the maximum deficient rainfall in the country during March 1-May 18, 2016.
While the normal rainfall the State receives during the period is around 106.5 mm, the actual rainfall it received was around 49.2 mm, a high deficit of 54 per cent not even recorded by desert States. On the contrary, neighbouring States like Chhattisgarh and Jharkhand have recorded almost normal rainfall during the specified period.
Above all, the IMD study on the trend in annual mean temperature variance in the country for the period of 1901-2015 reveals that India, except small pockets of Rajasthan, Gujarat and Bihar, is growing warmer as the annual mean temperature is rising. And, for Odisha, the bad news is the annual mean temperature variance was observed in the range of 1.5-1 degree C, the same as the rise in neighbouring States. But the aridity status as of April 2016, where more Odisha districts figured in moderate-severe dry list than its counterparts has worsened the weather phenomenon in the State comparably.
The prime reason behind the rising annual mean temperature in Odisha, as the IMD suggests, is the rise in both average maximum and minimum temperatures in the post-monsoon season in the State. This is a ‘red’ scenario for the State as it holds the risk of an increasing faceoff with tropical cyclones in the post-monsoon season.