Heat Wave ? The Silent Killer

Heat Wave – The Silent Killer
 

News: Recently, India’s Meteorological Department issued Heatwave alert across India.
 

What is a Heat Wave?
 There is no universal definition of heatwaves but prolonged period of excessive heat is referred to as Heat Wave.
 However, IMD has set certain criteria to declare heat wave.
 

IMD criteria:
 Heat Wave need not be considered till maximum temperature of a station reaches at least 40°C for Plains and at-least 30°C for Hilly regions.
 If the normal maximum temperature of a station is less than or equal to 40°C, then an increase of 5°C to 6°C from the normal temperature is considered to be heat wave condition.
 Further, an increase of 7°C or more from the normal temperature is considered a severe heat wave condition.
 If the normal maximum temperature of a station is more than 40°C, then an increase of 4°C to 5°C from the normal temperature is considered to be heat wave condition. Further, an increase of 6°C or more is considered a severe heat wave condition.
 Additionally, if the actual maximum temperature remains 45°C or more irrespective of normal maximum temperature, a heat wave is declared.
 

What are the concerns for India?
 According to a study, 90% of India is in ‘Danger Zone’, vulnerable to intense heat waves.
 Around 49% of Indian workers work outdoor (230 million plus workers) – Source Hindustan Times 2022.
 Since 1992, over 24,000 people have died in India due to extreme heat.
 15% decline in outdoor working capacity and extreme heat could lead potential loss in GDP of 2.8% by 2050. (Source - Al Jazeera)
 

What are the causes of Heat waves?
 Little pre-monsoon showers
 Decrease in moisture content in many parts of India.
 Impact of El-Nino
 Global warming and climate change 

Impact of Heat Waves

Heat stroke, Fatigueness, headache, nausea

Impact on labor and productivity

Food insecurity - Due to Drought events, crop loss

More energy demand, more carbon emissions

Crop yields suffer, farmer loses out on incom

Loss to Indian economy - Less productivity, decrease in agriexports etc

What actions should we take?
 Greener and more permeable urban surfaces can help reduce urban heat.
 Policies and guidelines on weather variability and urban heat management are needed at various levels.
 Restoration of ponds, lakes, wetlands can provide cooling effect in urban areas. Amrit Sarovar mission is a step in right direction in this context.
 Promoting the use of renewable energy sources such as solar and wind energy for cooling and electricity needs.
 Supporting farmers with resilient farming practices that take into account the risks of heatwaves, droughts, and water scarcity.
 Promoting the use of green roofs and cool roofs in buildings, increasing ventilation, and setting up green spaces.
 Passive cooling techniques such as natural ventilation, shading, and thermal insulation can significantly reduce indoor temperatures and energy consumption.
 Basic guidelines that pertain to people can be communicated well with people. For example, drinking butter milk, having onions in your diet, hydrating yourself at sufficient intervals, not roaming out in the noon hours, asking elderly people to stay indoors can be life-saving advices at times.