It’s no secret the Earth is getting warmer by the year, thanks largely to an international obsession with burning fossil fuels for automobiles.

That fact, among others, is why many urbanists are so dead-set on taking gas-powered cars off the roads and putting people on bikes and trains and other alternative modes of transportation.

Mapping out the next generation of transportation infrastructure, as researchers point out, will require planners to have a firm understanding of how heat travels based on vehicle use.

Now, thanks to new research by Geotab, a data analytics company focused on transportation-based research, hyper-local temperature differences are visible via interactive maps.

Geolab, for its “Heat in the City” map, studied data taken from hundreds of thousands of vehicles in order to illustrate temperature trends in the nation’s 20 most populous cities, per 2016 Census estimates.

Based on numbers drawn from June 21, 2017—the first day of summer and the longest day of the year—Atlanta clocked in at Number 8 on the scale of both highest temperature range and highest average temperature.

On that day, Atlanta’s temperature fluctuated a full 15 degrees, with 90 degrees being the highest and 75 degrees the lowest. The average temperature was 82 degrees.

Compare that to Los Angeles, which boasted a 37-degree temperature shift throughout the day, with an abnormal high of 108 and a low of 71 degrees.

Seattle, on the other hand, flaunted both the slightest temperature range and the lowest average temperature with 8 degrees and 67 degrees, respectively. At 111 degrees, Phoenix logged the country’s highest average temps.

Not surprisingly, Atlanta that day saw the highest temperatures north of Interstate 20, where the bulk of the region’s development and automobile traffic has been concentrated for decades.

It also appears that Atlanta is cooler near the Beltline’s Westside Trail and its Eastside Trail up until around Midtown, meaning the multi-use trail network’s area seems to be actually taking people from behind the wheel.

These kinds of realizations, according to Geotab’s vice president of data and analytics, Mike Branch, are crucial to developing transportation systems that help create energy-efficient urban landscapes and generally smarter cities.

“By leveraging data such as hyper-local temperature data,” Branch said in a press release, “cities are not only equipping themselves with the tools to make progressively informed decisions, but build safer and more sustainable communities for all.”