- India has increasingly been in the grip of more frequent and intense heat waves, as per a recent study published in Science Advances.
- On average heatwaves have slowed down nearly 8 km/day each decade and lasted longer by about four days — the effects being particularly drastic in North America and Eurasia.
- Heatwaves have also increased in frequency, from about 75 events averaged over 1979-1983 to about 98 over 2016-2020.
- Over the years, the jet stream, a fast, narrow current of air that flows from west to east high up in the troposphere has become weaker.
- The jet stream guides atmospheric waves, waves that are caused by the earth’s rotation and which influence the earth’s surface temperature.
- As the jet stream weakens, these waves also move more slowly, leading to more persistent weather events, and more spells of high and slow-moving heat.
- Along with natural climate variability and natural events, human activity and greenhouse gas emissions have also played a dominant role in rendering the slower-moving and longer-lasting heat.
Dig Deeper: What is the Heat Dome and Omega block weather phenomenon?
