Tornados and powerful storms are becoming increasingly common in parts of the world, including the Midwest and southern states in the United States and parts of Europe. With climate change, such storms are not only more frequent but can have devastating economic and social consequences.
Often electrical storms and activity can be a key predictor for even more severe weather, providing some advance warning before a devastating storm hits. Now, satellites and remote sensing tools are providing a way to better forecast and determine the severity of lightning.
Using Remote Sensing Technologies to Map Lightning
Satellites systems to monitor lightning are in greater need. The need for lightning detection had been known for some time, with NASA having launched the Lightning Imaging Sensor (LIS) aboard the Tropical Rainfall Measuring Mission (TRMM) satellite back in 1997. The system was able to detect cloud-to-cloud, intracloud, and cloud-to-ground lightning strikes.
The earlier Optical Transient Detector (OTD) sensor was also mounted on the OrbView-1 satellite, with the data used to make in 2001 of lighting activity. That satellite and system were active between 1995-2005, with the data mostly showing where lightning strikes occurred. It was clear, already early on, that potentially some lightning was being missed, particularly those with low signal.
The earlier tools were good at detecting the location of lightning, but were limited where lightning could be monitored, focusing mostly in the middle latitudes.
New Lightning Sensors on the International Space Station
Since the first LIS, a new LIS system has been installed on the International Space Station (ISS). The main advantage of the new system is it can capture lightning in more northern and southern hemispheres, expanding out from the middle latitudes that the previous LIS focused on.
Scientists now can use the new data to better measure not only location but horizontal and vertical extent of lightning strikes, giving them far more information about the intensity of a given strike. Increased geographic coverage now also means we have a better understanding of the global pattern of lightning strikes.
For instance, areas such as Lake Maracaibo in Venezuela, which has the highest intensity of lightning strikes in the world, has been determined to average 389 strikes per day. It is also clear now that lightning can even expand tens or even, on rare occasions, across hundreds of kilometers.
Using Satellites to Map Lightning
More recent satellite systems are now planned to host improved instrumentation for detecting a greater portion or even nearly all lightning strikes.
ESA’s Third Generation Meteostat Satellites
One such system is the European Space Agency’s third generation Meteostat satellites. The new instrument monitors over 80% of the Earth with real-time lightning imaging capabilities that incorporate new infrared sounding capability that enables the detection of severe storms. The instrument also uses four identical optical telescopes that supplement the infrared capabilities.
The first satellite slated to carry the new equipment is the MTG-I1 satellite, which is scheduled to launch in the autumn of 2022.
Geostationary Lightning Mapper (GLM)
There are other systems and tools scientists have used to measure lightning, including the Geostationary Lightning Mapper (GLM) satellite system. The single-channel, near-infrared optical transient detector has been used, along with ground-based observation stations.
The use of GLM to monitor single, major storm events has been very successful and has enabled a much better understanding of hurricanes. For instance, in a recent article, researchers were able to determine that during Hurricane Harvey, flash and pulse rates increased substantially in the hurricane’s eyewall and rainband.
The data demonstrated that this intensification served as a predictor for when the storm would intensify. In other words, researchers could use lightning data to better understand how severe a major storm could become.
This video shows the first transmission of Geostationary Lightning Mapper (GLM) data from NOAA GOES-17. On May 9, 2018, the lightning data in this video shows storms rapidly increasing and forming a line across the United States Plains.
Fast On-orbit Recording of Transient Events (FORTE) satellite
Similarly, the Fast On-orbit Recording of Transient Events (FORTE) satellite has demonstrate utility in measuring cloud-to-ground strikes. In this case, radio frequency proved to be effective. Such data allow greater insight to optically observed strikes, in particular clarifying signatures from other optical measurements and helping to determine the origin of where a given strike starts, given the proclivity of strikes to spread horizontally and vertically that can make the origin hard to pinpoint.
Improved Geospatial Technologies for Mapping Lightning
Improved systems and an increasing number of satellite tools are enabling better measures of lightning globally. These tools are critical if life-threatening storms are to be understood and proper precaution can be developed. While many of the new satellites still need further real-world testing and publication of their results, the early potential means we might be better able to forecast and understand storms before and while they are developing.
 For more information on the LIS system, see NASA’s article, “Lightning Spies”. See also NASA’s “A New Look at Earth’s Lightning” for more information on OTD.
 For more information on storm severity of hurricane Harvey as measured by GLM, see: Ringhausen, J.S.; Bitzer, P.M. An In‐Depth Analysis of Lightning Trends in Hurricane Harvey Using Satellite and Ground‐Based Measurements. Geophys Res Atmos 2021, 126, doi:10.1029/2020JD032859.
 For more on the use of FORTE satellite data for measuring cloud-to-ground lightning strikes, see: Peterson, M.; Light, T.E.L.; Shao, X. Combined Optical and Radio‐Frequency Perspectives on a Hybrid Cloud‐To‐Ground Lightning Flash Observed by the FORTE Satellite. Geophys Res Atmos 2021, 126, doi:10.1029/2020JD034152.