UIUC grad has the remedy for surging urban temps

Let’s face it, cities are where it’s at. But these thriving metropolises are heating up and fast. It’s no wonder such a global warming problem has caused quite the raucous.

Making sense of all that fuss is none other than Sushobhan Sen, a University of Illinois at Urbana-Champaign Department of Civil and Environmental Engineering December doctoral graduate.

Sen devoted the last six years to studying urban heat islands ― the phenomenon where cities are much warmer than their surrounding rural counterparts given the sheer amount of increased human activity that occurs in them.

“Essentially my topic was: How much hotter do they (cities) get?” said Sen, who also holds bachelor’s and master’s degrees in civil engineering from the Indian Institute of Technology at Roorkee and UIUC, respectively.

“As civil engineers, we make decisions that influence how hot cities get,” he added. “At the design stage, we (need to) figure out what we are doing right or wrong, so we can get a cooler or warmer city.”

Sen was the perfect candidate for the job. When his advisor, UIUC CEE professor Jeffery Roesler, approached him about the topic, Sen couldn’t help but draw from his own experiences with urban heat islands while living in Hyderabad, India, during a five-year stint in his father’s military career.

“I remember the first year I was there, the weather wasn’t so bad ― it was a little hot, but not bad,” Sen said. “But by the fifth year I was there, it was like 120 degrees in the summer.”

“In those five years, the city doubled in its size and the country’s GDP (Gross Domestic Product) doubled,” he added. “The city would actually warn us between 2 and 4 p.m., do not go out.”

“I literally saw the global impact ― I lived through that,” Sen added.

That experience lit a fire in Sen so bright that it not only guided his doctoral degree, but his life’s work as well.

“For me, it’s important,” Sen said. “I totally believe that cities are where the future is. Everybody is moving to cities because that’s where the opportunity is.”

“But cities have to be livable,” he added. “You can’t have tortuous places where everybody suffers. So the vision in this research and other research that people are doing will help make cities better places to live, but at the same time do it in a way that’s cost effective.”

The result?

Sen proved that reflective surfaces, such as lighter pavements, aren’t a cure-all for lessening the urban heat island effect; rather, it’s a case-by-case scenario.

“You have to really understand the form of your city, where your buildings are, how widely spaced the buildings are, and where the roads are, and then you have to figure out which roads are actually going to be useful,” Sen said.

“(In other words), you can’t just put reflective surfaces in a random place and expect to get any results out of it. You have to be careful with what you do.”

As for what’s next for Sen?

That fire remains ablaze in his new journey as a postdoctoral researcher with UIUC alumnus and University of Pittsburgh professor Lev Khazanovich.

“One of the things we want to look at is: how do the difficulties and challenges in collecting weather data affect pavement design?” he said.

“The problem is if you put a weather station next to a building versus if you put it next to grass, you’ll get different results because the grass is cooling down the air and the building’s heating up the air,” Sen added. “So my challenge is: how do you account for this? How do we fix the weather data? How do we clean it up and make sure we get reasonable results?”

Sen is certainly up for the challenge. But before bidding farewell to his alma mater, he has something important he’d like to say: “I would really like to thank my advisor, Jeff Roesler.”

“I’m really thankful to him for everything ― the leadership, the guidance, the funding,” Sen added. “He’s been my bedrock — someone that I can go and talk to and we can get things done.”

As for the future?

Sen dreams of becoming a professor and continuing his efforts to better city living.

“That’s my bigger vision ― to see how we can make cities better using engineering techniques,” he said.