Watch Real-Time Lightning On Earth Using ‘Sferics’: Warning, It’s Addictive!
We have the ability to detect lightning in a variety of ways. The use of radio waves is one of the coolest. Yep, I said radio waves but more on that in a moment. My colleague Dr. Thomas Mote made me aware of LightningMaps.org last week, and I have been taking a peek at it pretty consistently since then. It is really cool. I wrote this article to make you aware of it, but I love to use my Forbes articles to teach.
I didn’t know much about the effort but after digging through their documentation I found out that Blitzortung.org is behind the effort. It is somewhat of an organized crowdsourcing project. The Blitzortung.org website states,
“Blitzortung.org” is a lightning detection network for locating electromagnetic discharges in the atmosphere (lightning discharges) with VLF receivers based on the time of arrival (TOA) and time of group arrival (TOGA) method. We are a community of station operators who send their data to the computing servers, programmers who develop and/or implement algorithms for locating and visualizing of sferic positions, and people who assist in any way to keep the system running. There is no restriction on membership. All people who keep the network in operation are volunteers. There are no fees, terms and conditions, and no contracts.
From what I can tell, they are detecting Very Low Frequency (VLF) signals associated with lightning discharges. These signals are typically in the 3 to 30 kHz frequency range. GPS receivers are used to register the arrival times and location of the signals. These lightning discharge impulses are called “sferics (short for atmospherics).” A group at Stanford has long pioneered lightning geolocation technology using VLF also..
Lightning over the United States on June 30 2016 via Blitzortung.org and contributors. LightningMaps.org and Iweathernet.com/lightning provided the map.
NASA has referred to sferics as one of the many classes of “Earth songs.” NASA points out that,
If humans had radio antennas instead of ears, we would hear a remarkable symphony of strange noises coming from our own planet. Scientists call them “tweeks,” “whistlers” and “sferics.” They sound like background music from a flamboyant science fiction film, but this is not science fiction. Earth’s natural radio emissions are real and, although we’re mostly unaware of them, they are around us all the time.
Lightning is the primary source of sferics or VLF impulses. Sferics can travel for thousands of kilometers and even around the world. The ionosphere, beginning some 90 km above the ground, is a good reflector of VLF waves. Lightning is happening somewhere on the planet at almost any time (roughly 100 times per second according to NASA) but the surface-to-ionosphere VLF wave guide is most optimized around sunset or dawn. That sizzling sound you may hear in a radio speaker after nearby lightning is a result of sferics. A good primer on the effects of Earth’s upper atmosphere on radio signals can be found here.
John Trostel, an atmospheric physicist and director of the Severe Storms Research Center at Georgia Tech Research Institute said,
While the data does not have the spatial precision of larger commercial networks, such as the National Lightning Detection Network used by the NWS (provided by Vaisala), the data from the Blitzortung network is freely available. It is useful as long as the reduced precision is understood. The estimated ground strike points are up to 5 km in error, versus less than 1 km error for the commercial CG lightning networks.I find the blitzortung.org data very useful as a check on the operations of the North Georgia Lightning Mapping Array (NGLMA).
Private sector meteorologist Chris Robbins, founder of www.Iweathernet.com (one of my go to weather sites) told me,
since lightning is an underrated hazard, I wanted to provide a free service to my users that will enable them to track areas of lightning down to street level. Users can animate 2-hours worth of lightning data, and even superimpose lightning density maps.
Radio waves in Earth’s Atmosphere. Courtesy of NASA.
As for Lightningmaps.org, they do offer this disclaimer,
The data provided by Blitzortung.org is for entertainment purposes only. We are not liable for the completeness, timeliness, quality and accuracy of the information on our website.
There are commercial lightning data providers that have been collecting lightning data for a long time. There are also various satellite systems that have (or will) provide lightning information as well. The National Weather Association has provided a relatively comprehensive list of lightning networks and providers. There are also several regional lightning mapping arrays, such as the North Georgia Lightning Mapping Array, emerging.
Before closing I must mention how excited many of us are about the next generation weather satellite GOES R, which NOAA plans to launch in November 2016. It will have many advanced features including a lightning mapper. Lightning mapping from geosynchronous orbit will be a game-changer in the weather enterprise as lightning activity has been shown to possibly be a predictor of some types of severe weather. The National Severe Storms Laboratory (NSSL) explicitly states,
(the) Geostationary Lightning Mapper (GLM) will detect both cloud-to-ground and inter-cloud lightning. This will help severe weather forecasters identify rapidly intensifying thunderstorms so they can issue accurate and timely severe thunderstorm and tornado warnings.
By the way, when you go to the Lightningmaps.org detection website, be sure your volume is up so you can “hear” the sferics…..It has audio.
Dr. Marshall Shepherd, Dir., Atmospheric Sciences Program/GA Athletic Assoc. Distinguished Professor (Univ of Georgia), Host, Weather Channel’s Sunday Talk Show, Weather (Wx) Geeks, 2013 AMS President