Here’s What You Need to Know About Heat Waves as Summer Heat Begins

Heatwaves are becoming more intense and more frequent with climate change. Heat is rarely listed as the cause of death, making it an indirect killer with over 500,000 deaths each year. Most heat deaths come from illnesses that are made worse in warm weather, such as heart, lung and kidney disease.

Heat and Health Risks

High heat stresses the human body. Hot days with nights not cool enough to recover make the heart and kidneys work extra hard to keep the body cool. Heat also gives way to secondary health effects, such as more accidents, dirtier air, bigger wildfires and more frequent blackouts.

Those most at risk are people that are outside. Builders and farmers are most likely to suffer from heat exhaustion and heatstroke. Older people and those with underlying illnesses make up a bulk of the heat-related deaths. Women are more likely than men to die from heat. Poorer people without air conditioning, well-insulated homes and access to green spaces are also at a greater risk.

Sweat is the body’s best defense against heat. Sweating lowers internal temperatures as it evaporates. High humidity coupled with hot, sticky air makes the body struggle to keep cool since sweat clings to skin. Humidity in the heat makes a perceived temperature difference of a few degrees Celsius.

Heatwaves in a Changing Climate

Heatwaves are getting hotter. Over a century’s worth of fossil fuel pollution is clogging the atmosphere, which traps sunlight and heats the entire planet. Average global temperatures have risen by 1.3 degrees Celsius since preindustrial times; average land temperatures have risen by more than that.

There is evidence that climate change makes heatwaves worse by weakening the jet stream. This increases the occurrence of heat domes, which are areas of high pressure and heat that get stuck over a region for days or weeks. In order to adapt to heatwaves, cutting fossil fuel pollution is a huge first step. Protecting forests and wetlands that take CO2 out of the atmosphere is imperative.

Redesigning cities to have less concrete and cars and have more parks and water negates the urban heat island effect, which makes cities hotter than the surrounding rural areas. Buildings with air conditioning will lower deaths. Strong healthcare systems and swift emergency warning systems are also important.

To stay safe in the heat, it is best to stay out of the heat and avoid the outdoors during the hottest part of the day. If you do have to be outside, stay in the shade. Closing windows during the day and opening them after dark when outdoor temperatures are cooler than indoor temperatures. Remember to drink water frequently and wear loose clothing.