John Metcalfe was CityLab’s Bay Area bureau chief, covering climate change and the science of cities.
People often compare highways to arteries; Max Galka decided to make that literal.
Max Galka has dropped this one a little early for Halloween, but nonetheless it should be a timely distraction for both transpo nerds and fans of body horror. “Hourly Traffic on the U.S. Interstate, Visualized as a Living Circulatory System” is exactly what it sounds like—a portrayal of traffic volume on American highways that’s as bloody and vital as an open chest cavity on the operating table.
Galka, a data visualizer who lives in New York, writes on Metrocosm about the time-worn comparisons between interstate and circulatory systems. Each has passages of varying widths and complexity—veins and capillaries versus highways and residential streets—and each is responsible for ferrying resources to where they’re needed, whether it be cargo and the kids or oxygen and nutrients.
The information is submitted by each state [to the DOT] on a monthly basis. It includes hourly traffic counts for each hour of each day of the month at approximately 4,000 continuous traffic counting locations nationwide. The traffic counts are also broken down by road lane and direction of traffic, which, for the one month of data used here, amounts to a total of 14 million traffic count readings and a total of 6 billion vehicles counted.
The map includes only the U.S. Interstate. So unlike local traffic, which exhibits two daily “heart beats,” morning and evening rush hour, this map follows a 24 hour cycle with only one peak. On the Interstate, traffic bottoms out at 2am and steadily climbs until reaching its highest point at 4pm.
A quick scan reveals massive traffic flows—arteries that look like they’re about to bust and spray corpuscles everywhere—in Southern California, Dallas/Fort Worth, all along the Northeast Corridor, and throughout the Midwest. Head to the full-screen version for options to pan and rotate, as well as zoom in for grody scenes like this: