According to research released on May 17 by an international team of climate scientists working as part of the World Weather Attribution organization, human-induced climate change increased the likelihood of the April 2023 heat wave affecting Bangladesh and India by 30 times.
In their analysis, which also examined the recent heat wave that affected parts of Thailand and Laos, it was concluded that without climate change, the heat wave would have been “virtually impossible” in these nations. Additionally, the analysis stated that as global warming continues, there is a greater chance that an occurrence similar to the humid heat wave of April 2023 may occur again. If we go over the 2°C warming threshold, it will grow by three times in India and Bangladesh, indicating that such an event might happen every one to two years.
There are still improvements to be made, the authors noted, such as ensuring differentiated vulnerability assessments that take into account factors like gender, economic status, and occupation. The authors noted that while India is better off when it comes to having systems in place to prepare for and deal with heat waves (such as Heat Action Plans), there are still more improvements to be made. They said that policies should take into account social protection systems like the compensation measures set up for vulnerable groups.
The Heat Wave In April 2023:-
The second to fourth week of April this year saw warm temperatures across much of South Asia. Thailand and Laos saw extremely high temperatures around this period. The temperature in Tak, Thailand, as well as two cities in Laos, reached its highest level ever. Mercury reached 40.6°C during the hottest day in Bangladesh in several decades, and numerous incidences of heat stroke among individuals were reported.
April was very warm everywhere, including India. On April 17, Pragyaraj in Uttar Pradesh recorded 44.6°C. The north, center, and east of India, including the states of Maharashtra, Bihar, Odisha, and Delhi-NCR, experienced the heat wave conditions predicted by the India Meteorological Department (IMD) over the past few days. In April, 16, 13 individuals died in Navi Mumbai, Maharashtra, as a result of heat exhaustion at a public event; other reports indicated that over 600 people were hospitalized
23 climate scientists who are a part of the World Weather Attribution group (a collaborative project between several international institutes, including the Indian Institute of Technology that conducts rapid attribution analyses to assess the role of climate change in the occurrence of an extreme weather event) gathered to study this heat wave and see if it was connected to climate change in any way. The researchers investigated the extended heat wave conditions that occurred over areas of South Asia using observed temperature data and climate model simulations. They calculated an average Heat Index (HI) over four days for two distinct regions: central and southern India (the states of West Bengal, Rajasthan, and Uttar Pradesh)..
Climate change’s role :-
The team discovered that between the second and fourth weeks of April, considerable portions of both South Asian areas experienced an estimated HI values above 41°C, which is deemed “dangerous” for the human body to adapt to the temperature increase. It even got close to 54°C in a few places, which is “extremely dangerous” for human life.
They discovered that the likelihood of the April 2023 heat waves in Bangladesh and India was 30 times higher due to climate change. Such an event, which has the potential to happen once every five years, is now 2°C hotter than it was in the past due to climate change. According to Mariam Zacharias, one of the report’s co-authors, the heat waves that swept across Thailand and Laos would have been “virtually impossible” without climate change. Without climate change, the occurrence of this event in Thailand and Laos would have been extremely uncommon.
Their climate models predict that humid heat events like the one that occurred in both locations in April 2023 will “strongly increase in likelihood and intensity” in the future. If we achieve the 2°C warming levels above pre-industrial times, the risk that an event like the humid heat wave that hit India and Bangladesh in April 2023 will repeat would grow by three times (occurring once every one to two years), the report concluded. In such a case, it would be ten times more likely in Thailand and Laos.
The paper said that whereas Bangladesh and India have created heat action plans, Thailand and Laos have not. According to the report, heat-related mortality rates have declined in areas where HAPs have been implemented, including India’s Ahmedabad and Odisha.
However, the researchers noted that “these solutions are frequently out of reach for the most vulnerable people, highlighting the need to improve vulnerability assessments and create interventions that take particular needs of particular groups into account.”