Learning from Lightning

Little by little, lightning sensors in space are revealing the inner workings of severe storms. Scientists hope to use the technique to improve forecasts of deadly weather.

For most people watching a thunderstorm roll in, the bolts of lightning are just streaks of white light setting the night on fire, ushering in the crackle and rumble of thunder. But these brilliant flashes of lightning - electrical discharges between the positive and negative regions of a thunderstorm - also illuminate the workings of the atmosphere, providing information about storms that can improve emergency response efforts, saving money and lives.

To harness this information, NASA utilizes a fleet of ground-based, airborne and space-based sensors to detect lightning and characterize the electrical behavior of storms - all in the pursuit of advances in climatology and "nowcasting."

More accurate and timely forecasting, or "nowcasting," would help people gauge evacuation measures, help aviation officials map routes and plan refueling operations, provide better storm tracking, prevent systems disruptions and minimize hazards to NASA's spacecraft launches. Another potential benefit is providing algorithms for forecasting the likelihood of forest fires.

"Incremental gains ... really translate into cost and life benefits," says Dr. Dennis Boccippio, an atmospheric scientist at NASA's Marshall Space Flight Center in Huntsville, Ala.

NASA The awesome power of nature.

Current ground observations require about five minutes to scan a storm and make a report on its characteristics. But, says Boccippio, "there's a lot of evolution that can go on in a storm within that five minutes." And infrared satellite observations - from which we get those famous hurricane tracking reports that dominate television weather coverage in the late summer and early fall - can take 20 to 30 minutes to scan the "disk" of the Earth that's visible to the satellite. As Boccippio says, and as many storm victims probably agree, "You pay the price for that." Updating lightning flash rates at one-minute intervals would benefit "nowcasting" efforts, according to Boccippio.