Preparing for more summer heat waves

Heat Wave PhotoClimate change is causing longer and hotter heat waves that take a toll on public health and on a community’s economy, prompting some local governments to take action.

Heat can be deadly. From 2006-2010, exposure to extreme heat resulted in 3,332 U.S. deaths. The elderly and the poor are among the most vulnerable due to pre-existing health issues and limited access to air conditioning. But young outdoor enthusiasts are also at risk. Five hikers died during a heat wave this summer in Arizona, where it got as hot as 120 degrees F.

Heat waves are not only dangerous, they’re also expensive. Extreme heat can damage crops and livestock, reduce worker productivity, drive up energy costs, and increase demand for water resources. A 2011 heat wave and associated drought in the Southwest and Southern Plains cost $12.7 billion.

A hotter, drier Southwest

While it’s hard to determine how climate change influences individual extreme weather events, we do know climate change exacerbates both their frequency and intensity.

In the Southwest, residents are expected to see an additional 13 to 28 extremely hot days (temperatures of 95F or hotter) by mid-century, and 33 to 70 additional days by the end of the century. Higher temperatures will also exacerbate droughts and fire cycles.

How to prepare

The Southwest region has already taken steps to prepare for the impacts of more extreme heat. This is especially critical for urban areas, where stretches of heat-absorbing concrete and asphalt create a heat island effect, increasing temperatures in some cities by up to 15 degrees above surrounding areas

In Southern California, the city government in Chula Vista is working to implement 11 strategies to help adapt to the impacts of climate change. They include using reflective or “cool” paving and roofing to reduce the urban heat island effect, and amending building codes to incentivize water reuse and lower demand for imported water.

In Arizona, the city of Phoenix’s Water Resource Plan includes short- and long-term strategies to deal with water shortage scenarios, including monitoring supplies and managing demand, developing increased well capacities for water storage, and coordinating with neighboring counties to secure additional water resources.

A council of local governments in Central New Mexico is working to determine the impacts of heat waves on infrastructure, including the role of extreme heat in degrading asphalt and pavement, and what types of pavement materials are most resilient to extreme heat.

Early efforts to improve climate resilience can help a community prepare for costly extreme weather events and more quickly bounce back from them. Local governments like the cities of Phoenix and Chula Vista and those in New Mexico are demonstrating strong leadership that can be an example for others. Coordinating with partners in state government and the business community, including through the C2ES Solutions Forum, can ensure local governments’ resilience plans provide maximum protection against the heat waves of the future.