Legend has it that Zeus hurled them impressively far across the sky – but what distances can lightning actually bridge and how long does the longest discharge take? Obviously, astonishing dimensions are possible, according to satellite data: According to the World Weather Organization WMO, the longest known lightning flashed over 709 kilometers far above the Brazilian sky. And in terms of duration, Argentina has a record holder: there a discharge lasted more than 16 seconds.
They twitch brightly out of the storm clouds, followed by a thunderclap: The energy of the lightning is provided by air turbulence, which causes large charge differences between certain areas of storm clouds. If they exceed a certain threshold value, there is a sudden discharge in which so much current flows that the flash channel lights up brightly and expands explosively due to the heat. The lightning bolts can not only strike the surface of the earth from the cloud, but can also twitch between storm clouds.
Targeting mega flashes
Nowadays, lightning can best be examined by looking from space: With the help of modern weather satellites, meteorologists can record the discharges and their characteristics in detail. Studies have already shown that, from a global perspective, there is a particularly violent crash in South America. As part of a study, the researchers led by Randall Cerveny from Arizona State University then specifically investigated the record holders among the flashes in the data from four modern satellites.
Her research revealed that the longest flash of lightning flashed across southern Brazil on October 31, 2018. He covered a horizontal distance of 709.8 kilometers. This corresponds approximately to the route from the south of England to the Swiss border.
The current record holder for the flash duration occurred on March 4, 2019 over the north of Argentina, the scientists report: its flash channel glowed for 16.73 seconds.
“These are amazing values for single-flash events. Such extremes impressively show what nature is capable of, ”says Cerveny. “However, there are likely to be even more spectacular flashes. We will be able to observe these when the lightning sensors become even better, ”says the scientist.
Source: World Meteorological Organization (WMO)