What kills more people than storms, floods and earthquakes? Heat.

A woman tries to cool off during a weeklong heat wave in downtown Milan, Italy, 2005. (Luca Bruno/AP)

By Jonathan Purtle

Hurricanes, tornados, floods, and earthquakes may be the most harrowing displays of Mother Nature’s power. But heat waves — with temperatures like today's possible record-breaker — are responsible for more deaths a year in the United States than all of the above combined.

About 700 people die each year from heat-related deaths — a toll that is projected to rise as global climate change brings heat waves that are hotter, longer, and more frequent.

Climate change is happening now, and existing data is sufficient to project the future impacts of excessive heat on the public’s health. The Centers for Disease Control and Prevention estimates that climate change will cause an additional 2,000 to 5,000 heat-related deaths annually by 2050. An article published Environmental Health Perspectives modeled seven climate change scenarios to estimate the number of excess heat wave-related deaths that are likely to occur in Chicago in the year 2100 — producing estimates that ranged from 166 to 2,217.

While it’s difficult to envision what anything will look like in the 22nd century, we can probably assume that socioeconomic inequalities will still exist and that future heat waves won’t affect all communities equally as a result. In his landmark book Heat Wave: A Social Autopsy of Disaster in Chicago, sociologist Eric Klinenberg showed how social forces shaped outcomes during the 1995 Chicago heat wave. Low-income, urban communities are at highest risk for excess heat-related mortality — in part due to lack of air conditioning access, trees, and green space.

People over the age of 65 are also at increased risk as they are less likely to sense and respond to temperature changes and more likely to have health conditions that can lead to complications in extreme heat. Checking in on elderly neighbors when temperatures rise is an easy way to say lives.

If you’re concerned about elderly loved one who might live too far away to check in on yourself, the Carrier Alert Program might be an option. A joint effort of the National Association of Letter Carriers and the U.S. Postal Service Postal, the program works by simply providing participants with stickers to put on their mailboxes. The sticker gives the go ahead for postal workers to contact local authorities if they notice unusual activity — such as elderly residents not picking up their mail for the first time in five years during a heat wave. The program saved the life of at least one California man during a heat wave.

While extreme heat poses a serious threat to public health, its consequences are largely preventable. Here are a few simple things you can do to stay safe:

  • Drink more fluids (non-alcoholic) than usual, and don’t wait until you’re thirsty to drink.
  • Stay in air conditioned places if you can, even if a mall or library for a few hours during the hottest part of the day.
  • Never, ever, never leave anyone (including pets) in a closed car. Kids die that way. A lot.

Check out the CDC’s heat web site for all sorts of details about the dangers of heat and how to deal with them.

Read more about The Public's Health.