Have you ever wondered how lightning forms? Have you thought about how meteorologists can detect lightning? Lightning is a mysterious phenomenon in weather prediction; it is impossible to predict accurately but can be tracked with a lightning detector. Lightning strikes occur thousands of times a day, and these devices provide earlier warning for severe storms, making lightning detection equipment a useful tool. How do lightning detectors work? We’ll answer that in this article.
Weather forecasters can predict the likelihood of a storm with heavy lightning. Unfortunately, individual lightning strikes are currently impossible to forecast, and the strikes are seemingly random and occur too quickly and frequently to predict. The lightning flash is really our only warning, except for the buildup of static electricity that sometimes precedes a strike.
What is lightning?
Lightning is a powerful electric bolt. Lightning occurs when there is a difference in the electrical charge in a thunderstorm cloud. The negatively charged particles move to the bottom of the cloud, drawn to the positively charged particles in the ground. Cloud-to-ground lightning channels electrons from the cloud to the ground, balancing the charge. Cloud to cloud lightning happens much in the same way, except this happens between two clouds.
How do lightning detectors detect lightning?
Lightning strikes are like giant electrical sparks, and each time lightning occurs, electromagnetic pulses are emitted that are detectable nearby on a radio. You’ve heard them before if you’ve listened to AM radio, the pulse is the crash of static you hear.
But there’s one problem with using these frequencies for lightning detection. There are other potential sources of electromagnetic interference. For example, other sources that emit strong electromagnetic signals could cause the detector to give a false reading, such as electric motors or even cell phones. Your car alternator can even interfere: that’s the low-pitched whine you hear sometimes on AM radio as your car accelerates.
So how can we tell where a lightning strike hits?
When lightning flashes occur, it produces an electromagnetic wave. This wave pattern is detected at an ultra-low frequency of 500Hz. Tuning the antenna to 500Hz is one way to filter out as many interference signals as possible.
There are three types of lightning detectors: mobile-based, ground-based, and space-based. Mobile and ground-based systems use similar methods to detect lightning and share data to determine the lightning strike location.
Handheld lightning detectors are mobile-based lightning detectors. These personal lightning detectors use a 500Hz antenna to detect radio waves that indicate lightning. While handheld detectors are less accurate than a system of ground, mobile, or space-based lightning detectors, they are still a more affordable option to detect a lightning strike. Other mobile-based detectors use the same method to locate lightning strikes.
One of the more accurate ways to detect lightning is using the triangulation method. The triangulation method uses two or more ground-based lightning detectors to approximate the distance and magnitude of the lightning strike. Additionally, using multiple devices reduces the errors caused by signal interference. The National Lightning Detection Network uses this method, which up until the launch of the new GOES satellites, was the most accurate form of lightning detection available.
The most modern method of lightning detection is the use of satellites. GOES uses radiation to determine the location of a lightning strike using a tool called the Geostationary Lightning Mapper (GLM), which detects lightning from space. Satellite detectors provide more accurate information on the intensity of the lighting because we can observe them directly.
Why is lightning detection important?
Global lightning fatalities range from 6,000 to 24,000 per year, according to the International Lightning Detection Conference. Lightning safety has become more important, and while the saying “when thunder roars, go indoors” is something you should follow, if you’re hearing thunder the lightning strikes are already too close. That’s why we recommend a lightning detector if you spend a significant amount of time outside during the spring and summer.
While we may not have an accurate method for predicting lightning strikes, where and when a lightning strike occurs is valuable data, forecasters can create more effective storm warnings with more data about where lightning strikes more commonly occur.
A more recently developed lightning prediction method
In a 2019 publication, researchers utilize air pressure, temperature, wind speed, and relative humidity data to predict lightning. They use artificial intelligence to correlate atmospheric conditions with records of lightning data to predict the location of a lightning strike. This method can detect lightning within a 30km radius in 10-30 minutes. While this method is not very accurate, it can predict the affected area and time range much faster than other prediction methods.
Over time and with more data, this method will become more accurate and precise. Since weather station data is readily available, weather station data can be paired with lightning detection data to improve the accuracy of the algorithms.
We hope we’ve answered your questions on how does a lightning detector work. Lightning detection technologies are constantly evolving. The more methods we have to forecast the location of a lightning strike accurately, the more accurate future lightning weather advisories can be in the future.