Superbolt Lightning: The Sky's Sword Spanning Hundreds of Kilometers

4. The Science Behind Super Lightning

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Super lightning's scientific underpinnings show an intriguing junction of meteorology, electrical engineering, and atmospheric physics. We must explore the intricate mechanisms controlling the generation and spread of these large electrical discharges as well as the special circumstances enabling their reach across such great distances in order to grasp this remarkable phenomena. Fundamentally, super lightning is on a much larger scale yet follows the same basic ideas as ordinary lightning. The process starts with the separation of storm system electrical charges. Typical thunderstorms cause this charge separation mostly inside individual clouds. In the case of super lightning, however, the charge separation occurs across a far greater area—often spanning several storm cells inside a Mesoscale Convective System (MCS). The remarkable scale of super lightning is derived from the structure of these MCSs. These big, orderly storm systems can last many hours or even days and span hundreds of kilometres. Individual thunderstorm cells interact and mix within an MCS to produce a large, linked network of electrical charge. Super lightning events find their basis in this vast charge network. The existence of what scientists regard as "charge reservoirs" inside the MCS is one of the key elements allowing super lightning. These are areas where electrical charges gather to an abnormally great degree. The air's resistance to electrical flow over far larger distances than in a normal thunderstorm can be overcome when the electrical potential between these charge stores becomes sufficiently strong. Super lightning's intricate method of spreading over the atmosphere is yet not completely known. According to present ideas, it combines a process called "relativistic runaway electron avalanches" (RREAs) with normal lightning leader evolution. High-energy electrons driven by the intense electric fields inside the storm clash with air molecules to produce a cascade of more electrons known as RREAs. By means of this method, the reach of the electrical discharge can be efficiently extended much beyond what would be feasible using only conventional breakdown mechanisms. The interaction of super lightning with the upper layers of the atmosphere is another vital feature. Certain super lightning episodes have been noted to reach the stratosphere and even the mesosphere, areas much above the usual height of thunderstorms. Researchers have been prompted by this vertical reach to look at possible links between super lightning and other upper atmospheric events including elves and sprites. Another area of ongoing study is the length of several-second super lightning events. One hypothesis holds that rather than a single, continuous discharge, the prolonged duration is caused by a sequence of fast, sequential discharges along the same path. High-speed camera data supporting this "restrikes" theory shows pulsating behaviour in several super lightning incidents. The power involved in super lightning is rather amazing. Super lightning events are thought to include energy transfers on the order of gigajoules or perhaps terajoules, while a normal lightning bolt might transport a few hundred megajoules of energy. This massive energy release has consequences for our knowledge of atmospheric electricity as well as for possible effects on the environment and human infrastructure. Recent research have also started to investigate how super lightning is produced in relation to aerosols and particulate matter. Some scientists speculate that some forms of aerosols could improve charge separation mechanisms or change the electrical characteristics of the atmosphere in ways that help super lightning to occur. Our evolving knowledge of super lightning forces us to rethink basic features of atmospheric electricity. These large-scale discharges imply that the environment can enable electrical structures and processes on dimensions much beyond what was formerly believed to be conceivable. From plasma physics to global atmospheric circulation models, this insight has spurred fresh directions of research in several disciplines. The science underlying super lightning is evidence of the intricacy and connectivity of Earth's atmospheric systems. Deeper knowledge of this particular occurrence as well as insightful analysis of the more general operations of the electrical and climatic systems of our planet will help us as we keep deciphering its secrets. Super lightning reminds us strongly of how much still has to be discovered about the natural world, even in events we considered to be familiar.