Turning on the heat

A scorching heatwave hit Delhi on May 15 when temperature surpassed 49°C to record 49.2°C. The national capital has been experiencing high temperatures surpassing 40°C during May. Heat waves usually occur in the months of March to June and in some rare cases even in July. The peak month of the heat wave over India is May. A heatwave is considered if the maximum temperature of an IMD weather station reaches at least 40C or more for plains and at least 30C or more for hilly regions. A 4.5 to 6.4-degree departure from normal is considered to declare a heatwave and a more than 6.4-degree departure for a severe heatwave. India reported record temperatures in March 2022, making it the hottest in 122 years since records began. Scientists say the accumulation of greenhouse gases in the atmosphere is contributing to India’s increased temperatures. Extreme heat disproportionately affects the poor and marginalized, who often have labour-intensive jobs that require long hours in the heat. The states of Himachal Pradesh, Haryana, Uttarakhand, Punjab, and Bihar have particularly witnessed soaring temperatures in the past few days, India’s weather department said. The heat wave has adversely affected agriculture especially wheat growers. Farmers say the unexpected temperature spikes have affected their wheat harvest, a development that could potentially have global consequences given supply disruptions due to the Ukraine war. As a consequence of fall in wheat production, the government of India has prohibited wheat export till the situation improves. Neighboring Pakistan has already experienced 50°C. The extreme heat wave across South Asia is a direct manifestation of rising global temperatures, an impact that climate scientists had predicted with certainty years ago. The problem of extreme heat that lasts for weeks on end will only get worse as rising levels of greenhouse gases continue to trap more heat in the atmosphere, and it will be compounded by the arrival of more people to crowded cities in India and elsewhere. India’s urban population is expected to double by 2050 – and so too is the loss of productivity from people unable to work in the heat. The north east is facing consequences of climate change with abnormal weather causing heavy rains. Extreme rains upstream across the border in India and inside Bangladesh for the second consecutive day, has also triggered floods in the north-eastern region where water levels in more than 80 per cent of the rivers rose during the past 36 hours. Several states in the region experienced heavy rainfall, more than the usual for the month that triggered landslides, flooding and damages to infrastructure and properties besides resulting in several deaths. One of the reasons the short-lived spring season has metamorphosed into summer is the accumulation of greenhouse gases in the atmosphere, besides local weather conditions, scientists said. The number of heatwave days in India is increasing at a rapid pace every 10 years, an ongoing study by the Met Department showed. From 413 in 1981-90 to 575 in 2001-10 and 600 in 2011-20, the number of days that see extremely hot days is persistently increasing at 103 weather stations, mostly in inland areas, the study showed. These serve to remind on how human activities for development has instead contributed immensely towards climatic catastrophe and unless it is slowed, the green planet earth will turn desert yellow.