The world is experiencing extreme heatwaves and rising temperatures, with Europe facing a heatwave dubbed the "week of hell" in Italy, China and the US recording temperatures above 50C, and the UK recently experiencing its hottest June ever.

The United Nations has warned that we are now in the era of "global boiling," emphasizing the urgency of the climate crisis.

As temperatures soar, the impact on human health becomes a critical concern. A heatwave experiment conducted by Prof Damian Bailey from the University of South Wales offers insights into how the human body reacts to extreme heat.

The experiment takes the participant, in this case, a reporter, through a controlled increase in temperature, simulating typical heatwave conditions.

At 21C, the reporter begins to experience changes in their body as the temperature rises. Blood vessels near the skin's surface dilate to facilitate heat loss, resulting in a reddening of the skin. Sweating increases to help regulate body temperature, with evaporation providing a cooling effect.

However, at higher temperatures, such as 40.3C (equivalent to the UK's hottest day), the body faces greater challenges.

Heart rate increases significantly, and the brain's blood flow decreases, affecting short-term memory.

The experiment highlights the importance of managing both temperature and humidity during heatwaves. High humidity levels can impair the body's ability to cool down effectively, making it dangerous when core body temperature rises rapidly.

With heatwaves becoming more frequent, longer, and more severe, this poses a serious health risk.

The human body is designed to operate at a core temperature of about 37C, but as temperatures approach 40C, the risk of heat-related illnesses and organ failure becomes critical.

Vulnerable populations, such as the elderly and those with pre-existing health conditions, face greater risks during heatwaves.

Coping with extreme heat requires staying in the shade, wearing loose-fitting clothes, avoiding alcohol, keeping homes cool, refraining from exercise during peak heat hours, and staying hydrated. Sunburn should also be avoided, as it can impair the body's ability to regulate temperature and sweat.

Addressing climate change is crucial to mitigate the impact of heatwaves.

Without action, temperatures are projected to increase significantly by the end of the century, making extreme heat events more frequent and severe.

Understanding the effects of heat on human health and taking appropriate measures to adapt and protect vulnerable populations is vital in this changing climate scenario.