As India endures a record-breaking heatwave, former director-general of India Meteorological Department (IMD) Dr KJ Ramesh says the country is witnessing impacts of global warming sooner than expected.
“We have already crossed the 1.2℃ warming from pre-industrial era so these changes are expected. But we did not anticipate them so soon,” Dr Ramesh told News18. “India is among the first countries to record such intense heatwaves so early on this year. The average mean monthly temperatures for April are around 30℃, but the anomalies we are seeing are much higher.”
Heatwaves are common in the sub-continent in April and May, but the way mercury has soared to record highs so early on this season has caught the attention of climate scientists worldwide.
March broke the record for highest-ever average maximum temperatures of 33.1℃ in last 122 years, with two long spells of heatwave that extended from the hilly areas of Himachal Pradesh to the coastal areas of Maharashtra.
According to Dr Ramesh, who has also served as advisor to the ministry of earth sciences on matters of atmospheric sciences and climate, the incidence of heatwaves in March was exceptional. “We were expecting these changes possibly after 2025, leading on to 2030. But they are happening now, and are likely to get intense and possibly more frequent in coming years,” he says.
The scorching heat coupled with a staggering rainfall deficit of 87% in the northwest also took a toll on the seasonal wheat harvest with the overall yield plummeting down by 6-8 quintals per acre. Such is the situation that farmers in Punjab and Haryana are even running out of fodder (wheat straw) for the cattle due to low yields, compelling the state governments to ban its inter-state transport. The power outages amid shortage of coal have worsened the woes across cities and towns in several states.
Accelerating Global Warming
According to the former IMD DG who led India’s weather department from 2016 to 2019, heatwaves are likely to get stronger with the rapid thinning of the Arctic Sea ice which is now at its all-time low due to global warming.
“The fast melting of Arctic Sea ice has affected the global circulation patterns and it is likely to lead to a warmer northern hemisphere. The solar radiations, which were otherwise reflected by the frozen ground, are now being absorbed by the oceans,” he contends. “All these changes are likely to make the weather extremes like heatwaves more intense and pronounced in coming years, especially in the tropics — South Asia including India.”
Will Fuel More Thunderstorms
Intense heating of the land will also fuel more thunderstorms, which is yet another weather extreme that continues to claim hundreds of lives every year. “As temperatures increase, and there are more heatwaves, these long spells will be broken by thunderstorms or dust-storms, which will also get intense and stronger,” he elaborates.
Such occurrences are common during hot and humid climate, when high temperatures on the land create massive amounts of warm, moist air that rises into the atmosphere, and forms a thunderstorm. This is also the reason why such storms are more common during periods of scorching heat. “Even some of the peninsular states like interior Karnataka and Maharashtra are witnessing more thunderstorm activity this summer,” he shares.
Human-led Ecological Changes
The climate change impacts have also become more pronounced due to the fast ecological changes, including deforestation, which has rendered vast areas of land exposed to direct sunlight that were earlier protected by green cover.
“Large-scale deforestation along the foothills of Himalayas for development purposes has disrupted the ecological balance and contributed to warmer conditions in those places. The situation in cities has worsened due to more dependency on air conditioners and the urban heat island effect which have increased temperatures,” says the former IMD DG. “It is just April, and we still have weeks before the monsoon hits the country.”