fire season

Hurricanes and wildfires

April 3, 2025 By EarthWise Leave a Comment

Early March saw more than 200 wildfires break out in the southeastern U.S. – a busy start to the region’s annual fire season. One fire in the Carolina Forest near Myrtle Beach scorched over 2,000 acres over a two-week period and firefighters were busy containing it and many other blazes.

Strong winds and an unusually long dry period have made fires more likely to ignite and be spread. Lightning strikes, power line sparking, backyard fire pits and leaf burning all can lead to wildfires under these conditions.

A weather disaster last year may be helping to make this fire season worse than usual. Hurricane Helene ravaged the Southeast last September, dumping more than a foot of rain in some locations and knocking over hundreds of thousands of acres of trees across the region.

Lots of dead trees lying on the ground allow sunlight to reach the ground and dry out all the biomass, including the trees. All of this desiccated plant material acts as kindling, providing fuel for wildfires. Fallen trees can be a fire nuisance for years after a hurricane, especially in the Southeast, where dried out pine needles are highly combustible. All it takes is an ignition.

In addition, all the fallen trees represent an access issue for firefighters as the logs block roads needed to reach the fires.

Research has shown that climate change is fueling more intense fires in the West. Whether the changing climate is having a major effect in the Southeast isn’t clear. But droughts are expected to become more intense and more frequent in the Southeast because of climate change and that isn’t good news for the likelihood of wildfires.

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How Hurricanes Can Fuel Wildfires in the Southeast

Photo, posted March 5, 2025, courtesy of the U.S. Army National Guard / Roberto Di Giovine via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

South American drought

November 13, 2024 By EarthWise Leave a Comment

Vast areas of South America have been gripped in drought conditions for months. Rivers in the Amazon basin fell to record-low levels in October. The drought has amplified wildfires, parched crops, disrupted transportation networks, and interrupted hydroelectric power generation in parts of Brazil, Bolivia, Colombia, Ecuador, Peru, and Venezuela.

The drought is related to the impact of the El Niño that was present for the latter part of 2023 and the first half of this year. El Niño typically shifts rainfall patterns in such a way that there is reduced rainfall in the Amazon. This is especially true during the dry season months of July, August, and September.

Forecasts earlier in the year warned that there would be extreme fire conditions during the dry season. Indeed, the Pantanal region that spans parts of southern Brazil, Paraguay, and Bolivia has experienced one of its worst fire seasons in decades. The lack of rainfall, low soil moisture, and drawdowns of groundwater helped to amplify fires and caused them to spread faster and farther.

The drought has strained power supplies in Brazil and Ecuador because hydroelectric power stations are producing less electricity. Snarled transportation networks with impassible rivers have left some communities struggling to get supplies.

Brazil’s National Center for Monitoring and Early Warning of Natural Disasters has called the current drought the most intense and widespread Brazil has ever experienced. Late October saw 293 Brazilian municipalities facing extreme drought.

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Intense, Widespread Drought Grips South America

Photo, posted August 13, 2010, courtesy of Colm Britton via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Canadian zombie fires

April 8, 2024 By EarthWise Leave a Comment

Canada’s 2023 wildfire season was the most destructive ever recorded. Over 6,000 fires burned nearly 71,000 square miles of land from the West Coast to the Atlantic provinces. The burned areas are roughly the size of the entire country of Finland and represent almost triple the amount burned in the previous year, which itself was a lot. Smoke from Canadian fires, particularly those in Quebec, blanketed many cities in the United States and made its way as far south as Florida.

An alarming aspect of the Canadian fire season is that it didn’t ever really end. Late in the winter, 149 active wildfires are still burning across Canada. 92 are in British Columbia, 56 in Alberta, and one in New Brunswick. In these places, the wildfire season is yearlong.

These overwintering fires have come to be known as zombie fires. They burn slowly below the surface during the winter. Many areas in the north contain porous peat and moss ground cover and these act as underground fuel for smoldering fires.

Wildfires have become more prevalent in Canada because the changing climate has brought about increases in the hot, dry, and gusty conditions that lead to drought.

Many of the zombie fires don’t pose an increased threat of triggering wildfires in the spring because they are in places that are already so charred that there is nothing left to burn. But others are in drought areas that are basically tinder boxes ready to burst into flame once spring arrives.

Overall, Canadian government officials are warning that this year’s wildfire season is likely to be even worse than last year’s, particularly in the Western provinces of British Columbia and Alberta.

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As ‘Zombie Fires’ Smolder, Canada Braces for Another Season of Flames

Photo, posted June 30, 2023, courtesy of P. McCabe / EU via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Overwintering Fires | Earth Wise

July 6, 2021 By EarthWise Leave a Comment

Fires that go on for long periods of time, surviving the snow and rain of winter to reemerge in the spring, are becoming more common in high northern latitudes as the climate warms. Such fires are called holdover fires, hibernating fires, overwintering fires, or even zombie fires. Whatever people choose to call them, this type of wildfire is occurring more often.

These smoldering fires start out as flaming fires but then enter an energy-saver mode. They start above ground but then smolder in the soil or under tree roots through the winter. They barely survive based on the oxygen and fuel resources that they have but can transition back into flaming fires once conditions are more favorable.

Dutch researchers used ground-based data with fire detection data from NASA’s Moderate Resolution Imaging Spectroradiometer instruments on the Terra and Aqua satellites to study fires in the boreal forests of Alaska and Canada’s Northwest Territories. They found a way to identify overwintering fires based on their unique characteristics.

Their data indicates that overwintering fires tend to be linked to high summer temperatures and large fire seasons. Between 2002 and 2018, overwintering fires generally accounted for a small amount of the total burned area in the region but in individual years with hot and severe fire seasons, the number can escalate. In 2008 in Alaska, for example, overwintering fires accounted for nearly 40% of the burned area.

Early detection of these overwintering fires could help with fire management and reduce the amount of carbon – which is stored in large amounts in the region’s organic soils – that gets released to the atmosphere during fires.

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Overwintering Fires on the Rise

Photo, posted September 14, 2017, courtesy of Andrew R. Mitchell/USDA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Turning Dead Trees Into Biomass Energy | Earth Wise

July 1, 2020 By EarthWise Leave a Comment

California has suffered from numerous large wildfires in recent years. The two largest in the past century took place in 2017 and 2018, and just these two alone burned nearly 750,000 acres, destroyed over 1,200 structures, and killed 24 people.

Apart from the fires, drought, the warming climate, and bark-beetle infestations have killed 147 million California trees since 2013, most of them along the spine of the Sierra mountains. These dead trees represent a significant danger in forthcoming fire seasons as they threaten to burn with enormous intensity.

There are now biomass projects in California that thin trees in overcrowded forests and remove dead and diseased trees and turn them into wood chips to supply community biomass facilities that burn them to produce heat and electricity.

Proponents say these projects help rebuild rural communities by creating jobs, while at the same time reducing fire risk.

There are critics of these programs who claim that they are damaging and destroying ecosystems. They also point out that burning forest fuels emits 50% more carbon than burning coal and three times as much as burning natural gas. This is true of biomass in general but is mitigated by the fact that it in principle the carbon can be recaptured by new forest growth.

However, the dominant argument about emissions is that wildfires emit far more carbon dioxide than biomass plants, or much of anything else, for that matter. In 2018 alone, California wildfires released 50% more carbon dioxide than California’s entire industrial sector. So, reducing the extent of wildfires is a big deal for many reasons.

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In California, A Push Grows to Turn Dead Trees into Biomass Energy

Photo, posted August 24, 2016, courtesy of the USDA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

More Extreme Wildfire Seasons | Earth Wise

April 29, 2020 By EarthWise Leave a Comment

According to a new study led by researchers at Stanford University, autumn in California feels more like summer now as a result of climate change, and this hotter and drier weather increases the risk of longer and more dangerous wildfire seasons.

The research team, whose work was recently published in the journal Environmental Research Letters, found that the frequency of extreme fire weather conditions in the fall in California has doubled since the early 1980s. Average temperatures during the season have increased by more than 2 degrees Fahrenheit, and rainfall has fallen by approximately 30%. The most pronounced warming has occurred in the late summer and early fall. That finding means that tinder-dry conditions coincide with the strong “Diablo” and “Santa Ana” winds that are typical in California at this time of year.

In recent years, these conditions have fed large and fast-moving wildfires across California. The state’s two largest wildfires, two most destructive wildfires, and the most deadly wildfire all occurred during 2017 and 2018, resulting in more than 150 deaths and $50 billion in damage.

Because summertime has typically been peak fire season, the recent spate of autumn fires is putting a strain on firefighting resources and funding. The ongoing COVID-19 pandemic could further strain emergency resources. Since fire-prone regions have historically shared wildfire-fighting resources throughout the year, the consequences of California’s extended wildfire season could have a global impact. (For example, California’s recent autumn wildfires have coincided with the beginning of wildfires in Australia).

The researchers highlight some opportunities to manage the intensifying wildfire risk in California, including limiting the trajectory of global warming in keeping with the targets identified in the United Nations’ Paris agreement.

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Researchers forecast longer, more extreme wildfire seasons

Photo, posted September 12, 2019, courtesy of the California National Guard via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Dangerous Smoke From Australia’s Wildfires | Earth Wise

January 13, 2020 By EarthWise Leave a Comment

Wildfires raging across Australia have devastated large swathes of land and prompted one of the largest evacuations in the country’s history. The fires, which have scorched approximately 20 million acres, have also killed 27 people and affected an estimated one billion animals at the time of this recording. The fire season, though still young, already ranks as among the worst in Australia’s recorded history.

Away from the flames, millions more in Australia are breathing unhealthy air as a result of the smoke from these wildfires. Wildfires release all sorts of dangerous air pollutants, like carbon monoxide and nitrous oxide. But wildfires also release fine particulate matter (more commonly referred to as PM2.5), which can be transported long distances. Breathing in these microscopic particles can lead to respiratory and cardiovascular problems. High levels of PM2.5 are particularly harmful to older people, young children, and those with weakened immune systems.

The Australian capital city of Canberra has been covered in a thick haze of smoke from nearby wildfires. Canberra recorded its worst air quality day on January 2nd, when levels of PM2.5 spiked to more than 200 micrograms per cubic meter during the worst hour.

Smoke has also been fouling Sydney’s air off and on for months, with PM2.5 readings hitting nearly 400 micrograms per cubic meter last month during the highest hour of pollution.

The U.S. EPA has in place an annual PM2.5 standard of 12 micrograms per cubic meter and a daily (or 24 hour) standard of 35.

According to the IPCC, southern Australia is expected to see increased risk of fire as the planet continues to warm. Regrettably, this could be the new normal.

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Millions of Australians Are Choking on Smoke From Wildfires

Photo, posted December 5, 2019, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.