There’s a category 5 hurricane brewing in Florida, but it won’t be making landfall on any of the beaches or sweeping away any buildings. This hurricane is man-made, and contained in a 75 foot-long acrylic tank at the University of Miami Rosenstiel School of Marine and Atmospheric Science. This Surge-Structure-Atmosphere Interaction Facility (SUSTAIN for short) is the world’s largest hurricane simulator—six times the size of its closest rival—and after years of planning, it’s up and running

The simulator is one part of a new $50 million Marine Technology and Life Sciences Seawater Complex at the university. It is “the size of a small house,” as Brian Lam at Popular Science put it, and can hold 38,000 gallons of saltwater. A series of paddles create ripples and waves of different sizes and velocity, and with the flip of a switch, a 1700 horsepower fan (“originally suited for things like ventilating mine shafts”) sends 150mph winds whipping across the water, transforming the tank into a roiling tempest. 

By studying conditions inside the SUSTAIN simulator, researchers hope to make more accurate predictions about how strong a hurricane will be, where exactly it will land, and what it will do to buildings. "Over the last 20 years our track forecasts have been getting better and better,” Brian Haus, chair of the Division of Applied Marine Physics at Miami University told “But the thing that hasn't gotten any better over the past 20 years is hurricane intensity forecasts." 

Haus, a self-proclaimed “wave-junkie,” wants to know how, at a molecular level, hurricanes gain strength over warm water, without having to actually put himself or anyone else in the middle of a real storm. “At sea, you have to deal with the real beast, but in the lab, we have the opportunity to create the hurricane when and how we want it,” he says. The sheer size of the tank lets researchers recreate realistic oceanic conditions, and because the tank has see-through walls (made of 3-inch thick acrylic), they can get a good look at what’s happening inside the storm they’ve created. They’ll be using cameras and lasers to measure the changes in the water and atmosphere. 

According to the NOAA National Hurricane Center, a category 5 hurricane will destroy most of the framed homes in its path. But Haus says “most of our building codes and models for how we build in coastal areas are not based on any real information about what happens in these conditions. At one end of the giant tank sits a miniature house, which will be rigged with sensors and put to the test to help researchers get a better understanding of how man-made structures fare in large storms.

The complex has been open for a few months and has already yielded interesting information about improving hurricane forecasting.