India Has Three New Heatwave Hotspots, Raising Mortality Risks
A new study, published in the International Journal of Climatology, analyzed heatwave trends over seven decades in India and identified northwestern, central, and south-central India as new heatwave hotspots. The findings have prompted concerns over greater mortality risks associated with heatwaves. Heatwaves have been rising in intensity and frequency in recent years.
In July, another study found that heatwaves killed more than 17,000 people in the last 50 years. These deaths comprise approximately 12% of all deaths due to extreme weather events (EWE) in the same time frame.
Further, the Intergovernmental Panel on Climate Change (IPCC) predicted worse heat extremes for the Indian subcontinent in the 21st century. “Heat extremes have increased while cold extremes have decreased, and these trends will continue over the coming decades,’’ it said.
The present study noted that it is important to recognize heatwaves as a human health emergency and adopt heat resilient strategies in vulnerable regions. Accordingly, the researchers identified the best performing regional climate models to predict how heatwaves will occur in the future.
Related on The Swaddle
A heatwave is declared in the plains when the temperature is above 40 degrees Celsius and rises by 4.5 degrees Celsius from normal. A “severe” heatwave is when it rises by 6.5 degrees Celsius.
Given the mounting loss of life and destruction, identifying vulnerable regions and designing interventions is crucial, according to the Department of Science and Technology (DST).
The research found that there is a southern expansion of severe heatwave events. Heatwaves (HWs) and severe heatwaves (SHWs) were correlated with high mortality rates in Andhra Pradesh and Odisha.
This “may put a greater population at additional risk of heat stress in a region already characterized by low diurnal temperature range or the difference between the maximum and minimum temperatures within one day, and high humidity,” the Ministry of Science and Technology said.
Related on The Swaddle
Heatwaves are caused by several factors, many of which are driven by human activities and climate change. High atmospheric pressure creating a “dome” over a region that doesn’t allow heat to escape is one factor. Changing precipitation patterns are another. The delay in the arrival of the southwest monsoon this year caused a nine-year temperature high in northern India. Hot, dry winds from the northwest also contributed to the extreme conditions.
Further, India’s average surface temperature increased by 0.8 degrees Celsius from 1880 to 2018, according to an El Dorado Weather report. An increase in greenhouse gases exacerbates the risks and effects of heatwaves, according to a 2004 study in Science journal.
Human-made changes to landscapes also play a role, according to an analysis of the deadly 2015 heatwaves in India that killed more than 2,000 people.
The worsening situation in India corresponds with current global trends. Recently, record-breaking temperature highs claimed hundreds of lives in the Pacific Northwest. A heatwave in British Columbia killed more than 400 people in a span of five days, and more than 60 deaths in Portland, USA. A 35-degree heatwave is also sweeping Europe, leading to concerns over increasingly unpredictable heatwaves triggering health catastrophes in the years to come.