lightning

Predicting Lightning Strikes

November 19, 2019 By EarthWise Leave a Comment

Lightning is one of the most unpredictable phenomena in nature. Approximately 100 lightning bolts strike earth’s surface every second, and each lightning bolt can contain up to one billion volts of electricity. Lightning regularly kills both people and animals and sets homes and forests on fire. It’s also been known to ground airplanes.

Researchers at EPFL – a research institute and university in Switzerland – have developed a novel way to predict where and when lightning will strike. The system relies on a combination of standard data from weather stations and artificial intelligence to predict lightning strikes to the nearest 10 to 30 minutes and within a radius of less than 20 miles. The simple and inexpensive system was outlined in a research paper recently published in Climate and Atmospheric Science, a Nature partner journal.

According to researchers, the current systems for predicting lightning strikes are slow, expensive, and complex, relying on external data acquired by satellite and radar. The new inexpensive system from EPFL uses real time data that can be obtained from any weather station, meaning it can cover remote regions that are out of radar and satellite range and where communication networks are lacking. The quick predictions from the system allow alerts to be issued before a storm has even formed.

The system uses a machine-learning algorithm that’s been trained to recognize conditions that lead to lightning. The researchers took into account atmospheric pressure, air temperature, relative humidity, and wind speed, among other things. After training the algorithm, the system was able to predict lightning strikes accurately nearly 80% of the time.

This system is a simple way to predict a complex phenomenon.

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Using AI to predict where and when lightning will strike

Photo, posted December 14, 2018, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Fire-Driven Thunderstorms

March 6, 2019 By EarthWise Leave a Comment

In 2016 and 2017, wildfires in western Canada spawned thunderstorms that ignited additional fires, in some cases tens of miles away from the original fire. These fire-triggered thunderstorms are technically known as pyrocumulonimbus clouds, or “pyroCb’s”.

The physics of pyroCb’s is complex. When super-heated updrafts from an intense fire suck smoke, ash, burning materials, and water vapor high into the air, these elements cool and form so-called fire clouds that look and act like the cumulonimbus clouds associated with classic thunderstorms. What is different is that the heat and particulates in the smoke almost always arrest the ability of the cloud to produce rain. Instead, what remains is a lightning storm that moves across the landscape, triggering more fires.

These PyroCb events appear to be happening far more often, producing more energy, and erupting in places where they have never been seen before. As the world warms, wildfires themselves are becoming larger and hotter. In the past decade, wildfires have been burning more than twice as many acres as they did before the turn of the 21^st century. Along with the growth in wildfire activity, there has been an increase in PyroCb events, and there are now an average of 25 per year in western North America.

Apart from starting new fires, pyroCb’s also have similar effects as moderate-sized volcanic eruptions. Smoke and aerosols from wildfires can rise high into the stratosphere, where they can linger for months. Eventually, the particles carried aloft in the atmosphere do come down, dumping dangerous chemicals on far flung regions of the earth. But unlike volcanic eruptions, which are relatively rare events, pyroCb’s are happening more and more each year.

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Fire-Induced Storms: A New Danger from the Rise in Wildfires

Photo, posted July 31, 2013, courtesy of Loren Kerns via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Spreading Like Wildfire

October 18, 2017 By EarthWise Leave a Comment

Last July 7th, 140 wildfires started up in British Columbia, triggering a state of emergency. By the end of the summer, more than 1,000 fires had been triggered across the Canadian province, burning nearly 3 million acres of forest, about 10 times more than the average over the past decade.