GLM will give scientists and forecasters the best view yet of total lightning activity, and provide an early indication of potentially intensifying storms before they produce severe weather at the ground. Understanding the frequency and location of lightning events is very important, since severe thunderstorms are often accompanied by a dramatic increase of the in-cloud lightning activity as they get stronger. Credit: David Selby. Alexander Popov.
Popov's lightning detector. A modern lightning detector at an airport. Credit: Famartin. Engineers inspect GLM instrument. It can record about images per second, which is fast enough to see the progression of lightning as it brightens different parts of a cloud.
The spatial resolution is about 8 km, which is about the size of a small thunderstorm, so each camera pixel can see about one whole small storm or part of a large storm. Some very large storm systems like squall lines have been seen to make lightning flashes that traverse s of kilometers across the storm! GLM lightning data provide many new applications for total lightning that were not possible over large areas of the country previously.
It can be used by aviation weather services to monitor the spatial coverage of lightning. It will be useful for climatological studies of total lighting and thunderstorm activity. It provides new information on the lightning in hurricanes before they make landfall. It provides information over a large area on storm conditions which may improve weather models and is currently being tested by NSSL scientists. When the ground is hot, it heats the air above it.
As the hot air rises, water vapor cools and forms a cloud. As air continues to rise the cloud gets bigger and bigger. In the top of the clouds the temperature is below freezing and water vapor turns to ice. Now this is what we consider a thundercloud. The ice particles then bump into each other as they move around and build up electric charges. Eventually, the entire cloud fills up with these electrical charges. The lighter, positive charges form at the top of the cloud while the heavier, negative charges sink to the bottom.
When these charges grow large enough, a giant spark occurs between them within the cloud. We call this in-cloud lightning. Some lightning happens in between the cloud and the ground. We call this cloud-to-ground lightning.
Total lightning is the combination of all in-cloud and cloud-to-ground lightning strikes. Lightning strikes give off pulses. When a cloud-to-ground lightning strike occurs it gives off a very large pulse of current. We call this large pulse of current a return stroke in cloud-to-ground lightning strikes. In-cloud strikes also have strokes, but on a much smaller scale. When a pulse happens, we can measure it in hertz like microwaves, AM bands, and FM bands. There are a lot of different bands within a radio we can use to detect lightning, including:.
Low frequency LF. Mid frequency MF. Very high frequency VHF. VHF is best for physics and scientific research, not operational lightning detection.
In fact, lightning prediction is a very misleading concept. While the name suggests the system can predict lightning before it happens, that is actually impossible. What these single-node prediction systems do is measure electrostatic force in the atmosphere.
This method has a few, huge problems. This can lead to a lot of false alarms. The last big issue with lightning prediction systems is that they are extremely difficult to place and maintain. To accurately detect lightning using radio waves, you need more than one sensor.
A lightning detection network is a great way to detect real-time lightning strikes because it has several sensors at least ours has over 1,! When lightning gives off radio waves in an electric field, we have lightning detection equipment to detect it. Our lightning sensors are antennae that look like metal cylinders. We have these cylinders all over the world. When lightning flashes and sends out a pulse, our lightning detectors pick up this pulse. Depending on where our sensors are, they will receive the pulse at different times: Those sensors located closest to the pulse will receive it first while those farther away will receive it later.
We will discuss the functionality and operation of lightning detectors and endeavor to unravel a few unanswered questions along the way. Lightning can be detected by detecting the radio waves emitted by lightning strikes in the concerned channels. This information is digitally converted for analysis. The lightning detector and the weather radar collaboration is what makes the detection easy.
In this combination, lightning detectors focusing on the electrical advances and weather radar focusing on the location and the amount of precipitation which allows us to assess the magnitude and the precise movement of the lightning.
Lightning is produced when a cloud takes a certain shape, and it is the weather radar that forewarns about the formation. It lets you know precisely when and where a shower cloud has taken the form of a thunderstorm. In some cases, lightning can occur outside the precipitation zone which rarely happens but happens. The sounds of these are still reverberated in the central zone of the precipitation.
Detection agencies across the United States, such as National Lightning Detection Network and Total Lightning Network, follow all kinds of lightning strikes, cloud to ground strike is most hazardous and can cause damage on a large scale.
Cloud to ground strikes has massive currents that can be detected in no time through these agencies operation. Nowadays, lightning detection can be done using phones and multiple portable detectors that can give you a vague picture of the thunderstorm and the lightning yet enough for you to assess the best course of action for yourself.
They use the same mechanism as professional detectors with a few variations. These personal lightning detectors are very basic in nature when comparing professional types of equipment. Moreover, professional detectors possess numerous sensors that give a lot of data with few clicks and snaps. Personal detectors lack largely behind in this sphere.
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