Lightning can strike, but it cannot hide from an ESA satellite

Lightning comes and goes in brilliant, terrifying flashes. With powerful enough satellites in orbit, all that crackling static in the world’s skies is brought into view.

The latest view of atmospheric electricity comes from Meteosat Third Generation, a European satellite launched in December. Its cameras can track and record lightning strikes, even the smallest and fastest, day and night, over more than 80% of the earth’s surface. It was the first of six such satellites that will eventually monitor the weather around the world.

Last week the European Space Agency released the first batch of images from the Meteosat orbiter, revealing flashes of lightning over regions in Western Europe, Africa and South America. The agency shared images as it calibrated the satellite with its partners before making it fully operational later this year.

The satellite’s Lightning Imager has four cameras, each with five lenses. The cameras can capture a single flash that lasts as little as 0.6 millisecond, much faster than the blink of an eye, and can take sharp photos at 1,000 images per second.

The National Oceanographic and Atmospheric Administration in the United States has been monitoring lightning strikes in North and South America since 2017, using the Geostationary Lightning Mapper aboard Geostationary Operational Environmental Satellites, known as GOES. The European system extends lightning detection to regions of Europe, Africa and the Middle East (with overlapping coverage in parts of South America) and provides significant technological improvements that will produce a wealth of data for weather forecasting around the world. world.

“First, we have better resolution,” said Guia Pastorini, project engineering manager at Leonardo SpA, the aerospace company that developed the imager on Meteosat. “We can detect even a single lightning strike, while GOES can only detect a group of events. And in terms of energy, we can detect weaker lightning.”

The imager data will be useful for weather forecasting, said Carlo Simoncelli, Leonardo’s program manager. Lightning is associated with tornadoes, and there is a large increase in lightning that stays within clouds about half an hour before a tornado strikes. Being able to spot it from space, Simoncelli said, “gives us the ability for early warning of events that can be catastrophic.”

The fact that the system is always active and producing data under all conditions is a great advantage. “It’s quite simple to identify lightning at night in the desert,” Ms Pastorini said. “But if you’re looking at lightning reflecting off the ocean or just during the day, it’s much harder.”

Steve Goodman, a recently retired senior scientist at the National Oceanographic and Atmospheric Administration who has spent the past 10 years working on the GOES satellites’ Geostationary Lightning Mapper, noted that Europe’s systems were based on decades-old ideas. At some latitudes in the far north, he said, the resolution of the cameras will be no better than that of American satellites. But he also said that the European imager’s higher overall resolution helped detect smaller and fainter lightning strikes.

“They’ve built a great system and all their data will be shared,” he said.

Whichever system is used, tracking lightning and its relationship to the intensity of hurricanes and tornadoes has significant benefits for airplane pilots, climate scientists and ordinary citizens, said Dr. Goodman.

“Emergency workers need to warn people accurately,” he said, “not too early, because it costs money, and not too late, because it costs lives.”