Feeling the heat at George Mason University
Written by Dr. Luis E. Ortiz
Figure 1: The walking urban heat mappers. From left to right: Aahelee Sarker (Climate Dynamics PhD), Luis Ortiz (AOES Faculty), Ivy Stempkovski (Climate Dynamics PhD), Austin Reed (Climate Dynamics PhD), and Debanjana Das (AOES affiliate faculty).
As I stepped onto the blacktop of Parking Lot A on the afternoon of August 28th, I noticed something sticky on my shoe. Thinking I had stepped on gum, I checked my sole to find it clean. What I did notice, however, was that I had left a print on the sealant used to repair cracks in the pavement. Curious, I knelt and poked at it, and was shocked at how easily the very hot surface gave in. The material was melting below my very feet.
This wasn’t any ordinary afternoon. That day, temperatures at the nearby Ronald Reagan National Airport reached 101°F, beating the previous record for August 28th by 2 degrees. Over 75 million people in the US received heat alerts from the National Weather Service as forecasts predicted hazardous heat from St. Louis to Washington, DC. Humid air made things worse as the heat index, which describes how hot it feels when accounting for humidity, was forecasted to reach over 109°F in parts of the Washington, DC metro region that day.
For researchers at the Virginia Climate Center (VCC), this swelteringly hot day wasn’t just an inconvenience or a good reason to stay cool indoors. This was likely our team’s last chance to field test newly developed hardware that would allow us to measure temperatures in amazing spatial detail.
Figure 2: George Mason University Student Michael G. Clark, with an early prototype of the vehicle-based urban heat island sensor.
Earlier this year, VCC heard from communities throughout the Commonwealth that urban heat is a growing concern in the face of record-breaking temperatures. Municipalities needed data to inform decisions that would impact their communities for years to come, but this data was often out of reach due to the costs and technical expertise required to obtain it. George Mason Professor of Geography and Geoinformation Science Dr. Matt Rice saw an opportunity to put the incredible capacity of George Mason’s students to work on this issue. He headed to The MIX and there met student Michael Clark, who quickly agreed to help us design the sensor platform and data collection pipeline. Dr. Rice notes the importance of student involvement as Michael’s innovative system helped these efforts to be “inexpensive, dependable, and replicable” and his “valuable experience in sensor systems and field computing allowed him to quickly replicate a state-of-the-art device to collect ambient temperature, pressure, humidity, and location, similar to systems deployed for federally sponsored heat watch studies.”
With the help of local planners in the City of Fairfax, Dr. Rice and his students identified several key areas of the City to collect data. Dr. Rice explained, “I spend time with my kids all throughout the City, on foot, on bicycle, and on the CUE bus. We were already familiar with areas that tend to be much hotter and areas that are distinctly cooler. As a scientist, I wanted to validate my own experiences with sensor data.”
By August, Michael and Dr. Rice had two working prototypes; one for pedestrians mounted in a backpack, and another to be fixed to a car. The forecast for Wednesday August 28th set off a flurry of communications that ended with a solid plan: Dr. Rice and I would organize students and others to measure temperatures throughout campus and nearby Fairfax City using a combination of driving, walking, and biking. A team of students would cover the main Fairfax campus by foot, while others would take the morning and afternoon driving shifts.
Figure 3: Backpack and Vehicle Urban Heat Sensors.
The participation of the volunteers here was not only a learning experience, but a critical component of the field campaign. They used their expertise navigating the campus to guide our path and took additional notes and measurements needed to validate our results. Maybe more importantly, working as a team kept our spirits up as we walked for over two hours in the blazing heat (with frequent stops for cold drinks and rest, of course).
The urban heat island collection effort on August 28th produced 15,670 individual point-based observations of temperature, pressure, humidity, location, and time. Moving forward, these observations will be processed with additional high-resolution land use data to create a detailed heat map for the local region and shared with our partners in the City of Fairfax, Fairfax County, and George Mason University. These maps will become a uniquely useful tool in, as Dr. Rice states, “helping GMU and the City of Fairfax formulate common-sense mitigation strategies for climate change.”
Figure 4: Temperature data collected by the Virginia Climate Center team.
Author
Dr. Luis E. Ortiz
Dr. Ortiz is a co-PI for the Virginia Climate Center and Assistant Professor in the Department of Atmospheric, Oceanic, and Earth Sciences at George Mason University
