Study: Periods of extreme heat are increasing even on days not classified as hot - Sarmad

A recent scientific study has shown that the number of hours people are exposed to extremely high temperatures during the summer is increasing globally at a faster rate than the number of days classified as hot, which could intensify the health impacts of rising temperatures in the coming decades.

The US technology and science news website Ars Technica reported that researchers from China’s Sun Yat-sen University based their study on analyzing temperatures on an hourly basis, rather than relying solely on daily temperature data. They found that the average exposure to extreme heat during the summer, currently around 270 hours, is rising at a rate of approximately 62 hours per decade.

According to the study’s models, the number of hours of extreme heat exposure could triple its current levels by the end of the century under a medium emissions scenario, and could increase by a factor of 4.5 if high emission levels persist.

The study highlighted that the increase would be more pronounced during nighttime hours. Some days not classified as hot could still experience periods of extreme heat, a phenomenon that is not captured when relying solely on the number of hot days. This could lead to increased thermal stress on the body and reduced periods of recovery and rest at night.

The results indicated that residents of low-income countries may face the largest increase in the number of hours exposed to extreme heat, underscoring the need to improve monitoring of heat-related risks and take appropriate measures to protect the most vulnerable populations.

Researchers emphasized that analyzing temperatures on an hourly basis provides a more accurate picture of exposure patterns to extreme heat, which can contribute to improved health risk assessments, the development of early warning systems, and enhanced adaptation plans for the impacts of climate change.

The study underscores the importance of adopting hourly thermal measurements to better understand the effects of heatwaves and to implement more effective measures to mitigate their health risks.