Tropical Storm Isaac, which became a Category 1 hurricane as it marched across the Gulf of Mexico Tuesday, is threatening a long stretch of the coast from Louisiana through the Florida Panhandle. Residents of those states are anxiously following the path of the storm, but beyond Google and Weather.gov, how will we know the trajectory of this particular hurricane?
Hurricane prediction is not always an exact science -- back in 2005, Hurricane Rita was projected to hit Houston, but missed the region entirely -- but the U.S. National Oceanographic and Atmospheric Administration (NOAA) is already on the case, developing new ways to forecast the track of hurricanes. The agency launched an experimental Wave Glider robot named Alex into the ocean weeks ago, hoping the unmanned drone can forecast the direction of future storms.
The Wave Glider: How It Works
The Wave Glider, which was built and introduced by Sunnyvale, Calif.-based Liquid Robotics in 2008, is an autonomous ocean vehicle designed to measure everything from wave movements to air pressure, which is completely powered by the waves and the sun.
"This allows it to run for long periods of time, because it never runs out of fuel," said Roger Hine, founder and CTO of Liquid Robotics.
The float, which is adorned with solar panels, contains most of the vehicle's major electronics, including its GPS unit, its satellite communications systems, and most of its sensors for measuring water temperature, wind speed, and various wave characteristics.
The Wave Glider can travel from point to point or remain stationary, and the highly configurable platform can continuously transmit data, even as it's collecting data of its own.
The Wave Glider has two components: a float on the surface, a glider on the bottom.
"As the waves move up and down, it holds the glider up and down through water that's not moving as much down below," Hine said. "So the glider turns that that up and down motion into forward thrust, and it swims along."
The rudder is the only actuator in the whole system, which goes left, right and center, and that points the wave runner where we want it to go.
"We basically came up with this concept for making wave energy into propulsion," Hine said. "It can be autonomous, or it can also be controlled from somebody sitting on shore. We've got satellite communications. For the first time, we can put instruments in the ocean without a ship to deploy them."
Wave Gliders: The Future Of Hurricane Path Measurement?
The violence associated with hurricanes -- high winds and thrashing waters -- are typically prohibitive for humans, and even air vehicles like helicopters. But these wave glider robots, which can theoretically drift in the ocean endlessly without refueling, could be able to monitor not just one storm, but storms occurring over an entire seasonal period.
Alex, which is actually the 100th Wave Glider robot built by Liquid Robotics, is currently adrift in the ocean north of Puerto Rico, measuring the wind, the temperature of the water and the barometric pressure, as well as the many features of waves like their direction and height. The NOAA believes Alex will find itself in a hurricane this coming fall.
The NOAA isn't quite ready to use Wave Glider robots like Alex to directly determine hurricane warnings and watches, but at the moment, the organization is taking notes and testing the device to assume these roles sometime in the near future.
Ed Lu, Liquid Robotics' chief of innovative applications, says his company plans to compare the hurricane predictions without Alex to predictions with the Wave Glider's help, and see if their solution results in an improvement in the data.
"If this works as well as we think it might, that'll be a strong case for putting a lot of these systems out in the oceans," Lu said.