Gigantic jets have been observed and studied over the past two decades, but because there’s no specific observing system to look for them, detections have been rare. “More importantly, this is probably the first time that a gigantic jet has been three-dimensionally mapped above the clouds with the Geostationary Lightning Mapper (GLM) instrument set.” “The fact that the gigantic jet was detected by several systems, including the Lightning Mapping Array and two geostationary optical lightning instruments, was a unique event and gives us a lot more information on gigantic jets,” Mach said. “The VHF and optical signals definitively confirmed what researchers had suspected but not yet proven: that the VHF radio from lightning is emitted by small structures called streamers that are at the very tip of the developing lightning, while the strongest electric current flows significantly behind this tip in an electrically conducting channel called a leader,” Cummer said.ĭoug Mach, a co-author of the paper at Universities Space Research Association (USRA), said the study was unique in determining that the 3D locations for the lightning’s optical emissions were well above the cloud tops. He operates a research site where sensors resembling conventional antennas are arrayed in an otherwise empty field, waiting to pick up signals from locally occurring storms. ![]() Steve Cummer, professor of electrical and computer engineering at Duke, uses the electromagnetic waves that lightning emits to study the powerful phenomenon. 3 in Science Advances, a peer-reviewed, multidisciplinary, open-access scientific journal. Using satellite and radar data, we were able to learn where the very hot leader portion of the discharge was located above the cloud.”īoggs worked with a multi-organization research team, including the Universities Space Research Association (USRA), Texas Tech University, the University of New Hampshire, Politecnica de Catalunya, Duke University, the University of Oklahoma, NOAA’s National Severe Storms Laboratory, and the Los Alamos National Laboratory. ![]() “We were able to see very high frequency (VHF) sources above the cloud top, which had not been seen before with this level of detail. “We were able to map this gigantic jet in three dimensions with really high-quality data,” said Levi Boggs, a research scientist at the Georgia Tech Research Institute (GTRI) and the paper’s corresponding author. ![]() The upward discharge included relatively cool (approximately 400 degrees Fahrenheit) streamers of plasma, as well as structures called leaders that are very hot – more than 8,000 degrees Fahrenheit. Typical lightning bolts carry less than five coulombs between the cloud and ground or within clouds. The gigantic jet moved an estimated 300 coulombs of electrical charge into the ionosphere – the lower edge of space – from the thunderstorm. The Oklahoma discharge was the most powerful gigantic jet studied so far, carrying 100 times as much electrical charge as a typical thunderstorm lightning bolt. A detailed 3D study of a massive electrical discharge that rose 50 miles into space above an Oklahoma thunderstorm has provided new information about an elusive atmospheric phenomenon known as gigantic jets.
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