Source Alert

USC experts warn of summer heat waves and offer solutions

July 01, 2021

Summer is here and the heat is on for much of the United States. The U.S. West is experiencing extreme drought conditions while temperatures in the Pacific Northwest and parts of British Columbia soared to records of about 116 degrees this week. Rising global temperatures and urban heat island effects pose risks to human health and the environment. USC experts discuss the urban future, disparate impacts of heat and potential solutions.

Contact: Gary Polakovic (323) 527-7770 or


Light clothes, less booze and common sense help beat the heat

Dr. Carolyn Kaloostian is a clinical associate professor of family medicine and geriatrics at the Keck School of Medicine of USC.

“Heat waves can be very dangerous. When temperatures soar above 90 degrees, caregivers for young children and older adults should take precautions. It can lead to heat cramps, heat exhaustion and even heat stroke, which can be deadly. People need to take extra precautions during heat waves,” Kaloostian said.

She added:

  • Be careful consuming alcohol during Independence Day weekend as it can impair the body’s ability to regulate temperature.
  • Avoid strenuous physical activity, seek shade, drink cool water or sports drinks during the hottest part of the day.
  • Outdoors, wear light-colored and loose clothing, a hat and sunscreen level 15 SPF or greater.
  • Don’t linger in a parked car, which can gain 20 degrees in 15 minutes during summer, even with the windows cracked open.



Big cities will need lots of shady trees to keep cool


Esther Margulies is associate professor of landscape architecture and urbanism at the USC School of Architecture. She’s an expert in sustainability and open spaces.

“Urban heat waves haven’t really been on the radar for some of these cities in Canada or the Pacific Northwest as the climate changes, but they will experience more extreme heat waves,” Margulies said. “Cities are where the action will be in the 21st century, and the urban future means more people and density, so we’ve got to think about ways to make cities more habitable, greener and equitable.”

She added:

  • Trees are the most cost-effective protection against extreme heat.
  • A canopy of shade can cool pavement about 30 degrees compared to exposed surfaces.
  • Trees take decades to grow, so urban planning and infrastructure projects need to include space and funds for planting trees now and in the future.
  • Southwest cities such as Los Angeles, Phoenix and Las Vegas need to plan future water supplies to support urban forests as important tools to mitigate extreme heat.


It’s very hot, and going to get hotter, due to climate change

Julien Emile-Geay is an associate professor of Earth Sciences at the USC Dornsife College of Letters, Arts & Sciences. He’s an expert in climate change and droughts.

“It’s not surprising to see heat waves in the West during summer, but I wasn’t expecting the Pacific Northwest to be hotter than L.A. this week,” Emile-Geay said. “This is an example of the kind of surprises that climate change has in store for us.”

He added:

  • Record heat and extreme dry conditions pervade the U.S. West now.
  • Breaking heat records is becoming an annual occurrence, “a telltale sign that the climate is changing rapidly.”
  • Reducing greenhouse gases is the only way out of the climate emergency, yet it will take deep cuts for a long time to stop the warming trend.
  • Limiting warming to 2 degrees Celsius, as identified in the 2015 Paris climate accord, will likely require cutting carbon emissions in half by the end of this decade.
  • “Regenerative agriculture” is one solution; growing different crops while reducing waste, pesticides and fertilizers helps soil capture atmospheric carbon. It can benefit farmers and rural communities while helping the planet.



Photo credits: Emile-Geay photo by USC/Peter Zhaoyu Zhou; top photo by Pixabay.