Charleston, MUSC participate in heat stress study to learn about the consequences of extreme heat

July 30, 2021
Measuring extreme heat using a Wet Bulb Globe Temperature measuring device.
Jordan Clark, a University of North Carolina geography doctoral student, sets up a Kestrel Wet Bulb Globe Temperature meter to measure the sun's heat as part of a national heat watch program. Photo by Sarah Pack

As they say in the South: It’s not the heat – it’s the humidity.

This describes Charleston’s muggy summers, especially during July and August when outside temperatures easily climb past the 90 degrees mark. Climate change driven by human-induced emissions of greenhouse gases can result in various changes, including sea-level rise, weather hazards and heat-related health risks to populations.

So, it’s no surprise that recent national and global weather events, such as extreme heat waves, hurricanes, droughts, wild fires and flash floods, are linked to climate change and global warming.

In recent years, climatologists and scientists have shown a growing interest in studying rising temperature changes and their causes, around coastal South Carolina, the Southeast and nationally. According to the National Oceanic and Atmospheric Administration (NOAA), 2019 was the second warmest year on record and the end of the warmest decade (2010- 2019) ever recorded. Extreme heat kills more Americans than any other weather event, but not everyone’s risk is the same.

“Every year, communities are noticing hotter temperatures that they’ve never seen before, and it’s happening in more places than usual,” said Charles “Chip” Konrad, Ph.D., director of the NOAA Regional Climate Center and professor of Geography at the University of North Carolina at Chapel Hill. “Temperatures are increasing and with potentially dire consequences to people, cities and the environment.”

On July 14, Konrad joined a cadre of collaborative experts as part of MUSC’s monthly Conversation Cafe series, addressing the topic of “Meteorology Behind Heat Stress.” The hour-long virtual presentation, hosted by MUSC Sustainability and Recycling, explored the latest heat research and the science behind it, how heat connects to health and an update on local projects addressing heat-related problems in Charleston in addition to other urban communities around the country.

Konrad, who is the principal investigator of the Carolinas Integrated Sciences and Assessments (CISA) team, arrived earlier that week to test customized equipment that measures heat stress, specifically Wet Bulb globe temperature (WBGT), around peninsular Charleston and surrounding locations. WBGT accounts for temperature, humidity, wind speed, sun angle and cloud cover (solar radiation) in direct sunlight. The heat index measures temperature and humidity in shady areas. Konrad and his team will use WBGT thermometers mounted to tripods. A separate research project will mount heat sensors on cars as they record temperature and humidity in various areas as part of NOAA’s HeatWatch Program, an urban heat island mapping campaign, which will occur July 31 in Charleston and participating cities.

According to Konrad, Charleston offers a unique geography and location to conduct this level of urban heat research. The city’s peninsular location – surrounded by a harbor with rivers, wetlands and ocean breezes – makes it ideal to study overall heat stress temperature and model it for future research. Results from Konrad’s data gathering research will be matched to satellite data to provide a more accurate picture of the city’s hottest locations, especially urban heat islands – areas of a city that are hotter than surrounding areas.

City planners, architects and community partners can use this information to make improvements, create environments and establish plans for future development, and specific groups and audiences can also benefit – from outside workers and people who exercise outside to student athletes who work out in practice fields during the summer. It also serves to make authorities aware of heat hazards so they are able to plan accordingly and protect the well-being of others.

Konrad’s team has created a useful WBGT forecast tool to monitor extreme heat. Combining WBGT data with the National Weather Service’s hourly forecasts for air temperature, relative humidity, dew point temperature, wind speed and degree of cloud cover and sun azimuth angle – researchers can determine a five-day forecast of WBGT for various Southeastern cities and locations.

In North Carolina, Konrad has successfully worked with coaches and high school athletic directors in public school districts to apply his forecast temperature tools to determine WBGT and other measurements that relate to temperatures at school practice fields. His team also established a color-coded warning system and guidelines to monitor heat throughout the day: green (80 to 84.9 degrees); yellow (85 to 87.9 degrees); red (88 to 89.9 degrees) and black (90 degrees and above. For example, if WBGT instruments measured black (90 degrees or higher), all outdoor sports practice would be suspended.

The Department of Labor’s Occupational Safety and Health Administration (OSHA) has set strict guidelines for employers to monitor the heat index, which protects outdoor workers from serious heat-related hazards and illnesses.

“Awareness of heat has always been a challenge. We need to do a better job communicating this to help audiences understand this and initiate important conversations within their own families, with coworkers, acquaintances and the general public. Our tool is geared toward high school athletics, but we’d like more people to understand its value and potential in improving the environment and communities we live in,” said Konrad.

Event co-speaker Jennifer Runkle, Ph.D., an environmental epidemiologist at North Carolina State University, spoke about the consequences of extreme heat and its direct and indirect impact on people’s health, especially during COVID-19.

According to Runkle, a warming climate can lead to increased premature heat-related deaths. Cold and hot temperature extremes can worsen conditions, such as diabetes, cardiovascular disease and mental health issues and pregnant women and their babies can be affected by hotter than average temperatures. Certain individuals with co-morbidities, by virtue of the medications they take, can have increased sensitivity to heat stress. Health effects of extreme heat, even small deviations from seasonal average temperatures in the summer are related to increases in population-level morbidity and mortality.

Runkle also spoke about the strain of 2020 with the pandemic, social injustices and natural disasters caused by the climate crisis. “The COVID-19 pandemic is a reminder that health risks must be continuously addressed as high priorities. The science is clear that the Earth’s climate will continue to change, and these changes will have adverse consequences to people’s health.”

Janice Barnes of Climate Adaptation Partners shared insights into what the City of Charleston is doing as a participant in several Charleston heat research programs, including Charleston HeatWatch. According to Barnes, Charleston is one of four cities in the Southeast selected to participate in this research and among a cohort of U.S. cities selected to study urban heat.

MUSC plays an active role in this project due in large part to its commitment to transforming the university campus into a place of optimal healing and learning through the creation of an urban landscape that invigorates, inspires and teaches through nature. This includes the Medical District Greenway as well as the MUSC Arboretum that boasts more than 2,500 trees located throughout the 90-acre main campus, a collection made possible with the support of individual donors who share the belief in the innate restorative power of nature and healing and wish to bring that healing to patients, families and caregivers.

Barnes also mentioned the value of incorporating heat-reduction strategies to counter identified heat risks in urban areas. As organizations and government agencies invest funds in building projects and improvements, landscaping spaces and future planning, she said that it’s also important to consider surface temperatures and select complementary materials for design.

Christine von Kolnitz is the director of MUSC Sustainability and Recycling and a proponent of providing a sustainable and healthy MUSC campus. She and several MUSC employees will serve as volunteers in this weekend’s Charleston HeatWatch data gathering, working with the City of Charleston and its team.

“I look forward to helping to gather crucial data on heat in the Charleston region,” von Kolnitz said. “This data will inform community leaders, businesses and the public in making many future decisions as to where to target resources to help any population that is not currently able to mitigate the health consequences of extreme heat.”

For more information, visit the CISA Heat Watch program.