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Better Planning for Coping With Heat Waves

Three Things You Should Know

1) The number of heat waves in the U.S. and around the world has increased, a likely consequence of rising average global temperatures.

2) Heat waves can cause heat-related illnesses and can increase the risk of death.

3) When preparing for a coming heat wave, policy makers should consider different communities’ needs and the socioeconomic links between heat waves and deaths, says a new study.

The Debrief

New Yorkers keep cool in a local fountain during a heat wave in the summer of 2010. Credit: Vasilios Sfinarolakis, flickr.

In the past few weeks, most of the country has been feeling the full force of winter, with both frigid weather and some big snowstorms. But less than six months ago, record-breaking heat waves struck many parts of the United States and around the world, as many as 19 countries set new all-time record high temperatures during the year. With such extreme temperatures can come heat-related health problems, and many regions of the world are just beginning to look at how to be better prepared to face more frequent and deadly heat waves in the future.

A new study published in the journal Global Environmental Change examines how important socioeconomic factors could be to planning for heat-related health problems. According to this review, a growing collection of data suggests that people’s susceptibility to heat isn’t limited to the outside temperatures, air quality, and their age — even though these are the kinds of factors that guide many heat wave emergency response plans. Research shows that the community a person lives in, how often they get out of their house, and their income level are all linked to how likely they are to suffer serious illness or death during a heat wave. Moreover, learning more about these additional factors could help planners better target those people in need of immediate help during extreme heat waves.

“An inner-city community with high rates of homelessness, poverty, over-crowding and substandard housing… will have very different needs from those residing in an affluent, verdant suburb where temperatures may actually be lower, air quality better and air conditioning far more widespread,” write the study's authors, from the University of Ottawa and the University of Calgary, in Canada. 

By reviewing a number of recent scientific studies, the authors of this new paper explain that people who are less likely to get out of their house during the heat wave are at greater risk for getting sick and that people living in the most densely populated areas, where closely-packed buildings can often raise the outside temperatures even higher, are also more likely to suffer. On the other hand, in suburban neighborhoods where people feel safer going outside their homes and have more access to clean water, people are at less risk.

Why This Science Matters

As the number of extreme heat waves has increased in recent years, so has awareness of just how deadly they can be. For example, a week of daily high temperatures between 90 and 105°F in Chicago in 1995 was attributed with causing over 700 deaths, and the 2003 European heat wave is credited with causing as many as 35,000 deaths. In response, a number of countries, regions, and cities around the world have implemented plans and response programs to cope with future extreme heat events and minimize their death tolls. 

In April 2010, the Interagency Working Group on Climate Change and Health released a report identifying areas where research can help inform how climate change is affecting human health. In one focus area on heat-related deaths, the working group pointed out that more research is needed to better understand which people are most at risk during extreme heat events. Though scientists have known for many years that people over the age of 65 are much more likely to die during a heat wave, a number of recent studies have uncovered that there are other factors that make people more susceptible to getting sick or dying during a heat wave.

Though many cities in the US, including Philadelphia, and Phoenix, Ariz., have plans in place to help deal with heat waves, only a few have begun to consider these newly identified socioeconomic risk factors. This new review of data on other risks may help planners develop more effective emergency response plans for future heat waves.

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