Mowing the Sky to Model Hurricane Ian’s Destruction

We’re at Autodesk University 2022 in New Orleans on a sunny Tuesday afternoon, but our attention is focused to the East, where Hurricane Ian has just ripped through Florida—from one side to the other—leaving behind unprecedented destruction.

We’ll be flying over the state, no question, said Kit Revell, VP of U.S. sales, at Nearmap’s booth in the exhibit hall. Nearmap is in the business of aerial photography.

At the request of Governor DeSantis?

We fly proactively, says Revell. We have the data available, so when governments and agencies need it, we can provide it.

While the aircraft may be ordinary, the camera is anything but. The most sophisticated camera Nearmap uses is capable of producing 3-inch resolution and could cost a million dollars.[i] It may not be able to read license plates like the spy technology you see in movies, but it is more than good enough to provide site planning and damage assessment—tasks that usually have to rely on low resolution, mostly flat imagery from Google Earth or Microsoft’s Bing Maps. On top of the 3D models, Nearmap adds an AI layer that helps identify objects on the ground.

Nearmap uses photogrammetry to create 3D models from photographs, unlike satellite imagery from Google Earth or Microsoft, which are 2D. With 3D models, the height of buildings and structures can be accurately measured.

The Cessna flies back and forth over a swath of land, in a technique Revell refers to as “mowing the sky.” Models can be viewed at a 45-degree angle. A toolbar has tools to help you measure distances, changes in height, areas and perimeters.

As you might imagine, the data storage requirement for all that imaging is immense.

“We’re in the top five of all AWS’ (Amazon Web Services’) customers for data storage customers,” says Revell.

Nearmap may not bother with a large part of the contiguous United States, but it covers most of what matters, say Revell. “We cover the land where 80-85% of the people live,” he says.

Nearmap flies over those lived-in areas repeatedly. This allows comparisons of before and after events. Events can be weather-related catastrophes, property crimes and insurance fraud.

“Our 3D models are used by insurance companies. Claims can be paid or denied based on our models. You don’t have to have a claims agent in the field.”

Customers subscribe to an area of coverage and are given access to every flyover for that area. You can use it like a time machine, according to Revell.

Nearmap does not use LiDAR, which would provide millimeter accuracy. That level of accuracy has not been requested by customers, says Revell.