Cities are hot and getting hotter, thanks to global warming and the urban heat island effect.  With urbanization on the rise globally, extreme heat threatens human health, strains energy grids, and impacts global economies around the world.

Extreme heat is now ranked as the number one weather-related killer in the United States.  With over eighty percent of Americans now living in cities, urban heat islands and record high temperatures could cause serious health problems for hundreds of millions of people during the hottest months of the year.

Climate Central just released an analysis of government records for summer temperatures in 60 U.S. cities (1970 to date).  This study found that single-day heat island differences reached 27 degrees F in some cities, and that since 2004, at least 12 cities experienced 20 additional days a year above 90°F than surrounding rural areas.

This study also ranks the top ten urban heat islands in the United States.  Washington, DC ranks number 6 on this hit parade of urban heat.

Climate Central has prepared a useful interactive tool to help you learn more.

You can read more about the study here.

You can also read GCCA studies on heat health problems in Washington DC, and learn about strategies to lower urban temperatures and save lives.