CSA Xpert

Heat wave occurrence depends upon certain thresholds of maximum temperature over a region. According to India Meteorological Department (IMD), to declare a heatwave, at least 2 stations in a Meteorological sub-division for at least two consecutive days should either record temperature departure from normal by 4.5°C to 6.4°C or record the actual maximum temperature ≥ 45°C in the plains. Similarly, a severe heatwave is declared when the temperature is departed from normal by >6.4°C or actual maximum temperature of ≥47°C. 

The daily mean temperatures both the maximum and the minimum have been gradually increasing in Odisha (average 0.42 °C increased in the last 15 years). Heatwaves affect most of the districts in Odisha (Government of Odisha, 2015). The overwhelming majority of people employed in the unorganized sector working for long-duration are affected the most. Heatwaves force people to stay indoors and lose out on income-earning opportunities (OSDMA, 2016). A major heatwave in 1988 killed around 1500 people, mostly in the coastal Odisha region. The highest maximum temperature during 1988 was 42.6°C. Again in 2002, the peak temperature was 44.5°C in May but the human loss was less because of increasing adaptive capacity and enhancing protective measures. The extreme temperature events have a varying adverse impact on agriculture. The loss in net revenue at the farm level is estimated to a range between 9% and 25% for a temperature rise of 2°C to 3.5°C (Devagowda et al., 2019).