Heat wave Vulnerability Index

India has got its own Heat wave Vulnerability Index. A Heat Wave is a period of abnormally high temperatures, more than the normal maximum temperature that occurs during the summer season in the North-Western parts of India. Heat Waves typically occur between March and June, and in some rare cases even extend till July. The extreme temperatures and resultant atmospheric conditions adversely affect people living in these regions as they cause physiological stress, sometimes resulting in death.

The Indian Meteorological Department (IMD) has given the following criteria for Heat Waves :

• Heat Wave need not be considered till maximum temperature of a station reaches atleast 40*C for Plains and atleast 30*C for Hilly regions.
• When normal maximum temperature of a station is less than or equal to 40*C Heat Wave Departure from normal is 5*C to 6*C Severe Heat Wave Departure from normal is 7*C or more
• When normal maximum temperature of a station is more than 40*C Heat Wave Departure from normal is 4*C to 5*C Severe Heat Wave Departure from normal is 6*C or more

Key Facts

• The Heat Wave Vulnerability Index divided 10 Indian districts in a Very High Category: – 4 from Madhya Pradesh, 2 in Chhattisgarh, and one each from Jharkhand, Gujarat, Rajasthan and Odisha.
• Another 97 of districts are in the High Category, while a bulk of them belongs to High Normal to the Low Normal category. A total of 75 districts are in Low category, while 10 made it to the very low category. Districts of Kerala, Goa and Lakshadweep belong to the category of least risk.
• The research was proposed in an article published on March 30 in the “International Journal of Environmental Research and Public Health”, an open access platform for peer-reviewed research. The districts were selected as units for analysis, the researchers evaluated demographic, socioeconomic, and environmental vulnerability.
• Population health was evaluated on the basis of immunisation of children and the presence of a health facility within 3 kilometers.

It was observed that districts with higher heat vulnerability are located in the central part of the country. On further examination, it was found that these areas are less urbanised, have low literacy rate and have less access to water and sanitation and health amenities.