‘Kolkata’s average summer temp rose by 0.2°C in 10 yrs’
Times of India | 7 July 2024
Kolkata: A senior official from Indian Meteorological Department (IMD), Alipore, highlighted the role of high humidity in exacerbating heat-related discomfort.
Kolkata’s average summertime temperature has risen by 0.2°C over the last decade compared to 2001-10 — it is 0.5°C for cities like Mumbai, Bengaluru, and Chennai — while relative humidity, too, has increased significantly in recent years.
A study led by environmentalist Anumita Roy Choudhury from Centre for Science and Environment (CSE) has found that Kolkata’s decadal average ambient air temperatures have showed insignificant change but relative humidity has increased by 5% between 2001-2010 and 2014-2023.
The study also found a 3.5% rise in the decadal heat index and a threefold increase in days with a daily heat index exceeding 41°C, indicating a dangerous heat level. Additionally, the study says monsoons in Kolkata are becoming more thermally uncomfortable than pre-monsoons due to a higher heat index.
The number of extremely hot and humid days, using 30°C wet-bulb temperatures (WBT) as a threshold, has also markedly increased. WBTs above 35°C are considered lethal for extended exposure.
As heatwaves may soon become more common, the report suggests the burden of power generation cannot rest solely on thermal plants, which are already operating near full capacity, and India should focus on expanding solar power capacity.