In 2020, a team of researchers from the National Bureau of Economic Research found evidence suggesting that if greenhouse gas emissions are not reduced, future heat waves could kill millions of people around the world. In their article, the experts described how they compared heat-related deaths in various countries during past heatwaves with projected future temperatures to learn more about possible deaths in the future. The scenario is quite disturbing.
But how can heat kill us?
First, keep in mind that extreme heat can harm anyone of any age, including the elderly, people with chronic illnesses, those from low-income families, outdoor workers, and athletes. competing in extreme heat conditions are among those most at risk.
Hyperthermia occurs when the body’s heat regulation system is overwhelmed by external heat, causing a person’s internal temperature to rise. Our core body temperature is approximately 37 ° C and, under normal health conditions, our bodies can generally withstand variations of approximately 3.5 ° C. However, if we pass this threshold, the body begins to show signs of distress. The body sweats to stay cool, so the problem begins when we become dehydrated or when the external mix of heat and humidity becomes too high.
In this scenario, sweat is not enough. As the blood moves towards the skin, it becomes red in an attempt to transfer heat away from the core. As salt stores decrease, muscles contract, and as the body activates an immune response, organs begin to swell. At this point it is possible to have hallucinations and confused ideas. Then vomiting, seizures, and eventually death can ensue as a result of a heart attack or organ failure.
Also known as heat stroke, it can cause death or damage to the brain and other internal organs. It usually occurs as a progression of milder heat-related illnesses, such as heat cramps, fainting, and heat exhaustion. It is the result of prolonged exposure to high temperatures, usually in combination with dehydration, which leads to failures in the body’s temperature control system. Heatstroke can also increase your risk of developing a heart condition, stroke, or breathing problems.
Staying well hydrated can protect against heat, but it may not prevent your body temperature from rising if the internal or external heating is excessive.
By 2100, exposure to heat will threaten the health of approximately 4 billion people, according to an International Labor Organization report published in 2020. The report predicts that the world’s productive working hours will decline by 2.2% due to increased heat, leading to economic losses of $ 2.4 trillion, concentrated in South Asia and West Africa.