thunderstorms

Rainforests and thunderstorms

August 6, 2025 By EarthWise Leave a Comment

Tropical forests are dying at an alarming rate, and not just from deforestation. Even intact forests are losing trees, threatening biodiversity, carbon storage, and the global climate. While drought and rising temperatures are often blamed, new research points to a surprising culprit: thunderstorms.

These intense, short-lived convective storms, common in the tropics, are increasing due to climate change. With strong winds and lightning, they can snap trees, strip canopies, and kill even the most robust tree specimens.

In a perspective paper recently published in the journal Ecology Letters, a research team led by the Cary Institute of Ecosystem Studies argues that thunderstorms, often overlooked in carbon storage research, may be the leading cause of tree death in tropical forests. The research team estimates that storms have caused 30 to 60% of tree mortality in the past, a number that is likely rising as storm activity increases 5 to 25% each decade.

Including storm data in forest carbon studies changes the picture significantly. Earlier models showed that carbon levels dropped sharply when temperatures rose beyond a certain point. But when storm impacts were added, that pattern disappeared, suggesting that storms – not just heat – may be a key factor in carbon loss.

Understanding which species are most vulnerable is critical for reforestation and conservation efforts. Mature trees store the most carbon, so if they’re lost to storms, future forests may fall short of their carbon storage potential.

As storm activity increases each decade, the stakes grow higher. Accounting for storms could reshape how we protect, restore, and plan for the future of our forests.

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Web Links

Are the Amazon’s biggest trees dying? Forest coroners investigate

Photo, posted July 2, 2017, courtesy of Anna & Michal via 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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Web Links

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.