What is Wildfire? What Causes Wildfire?

Wildfires erupt in many places these days. The Oak Fire in California has forced thousands residents to evacuate as it threatens to destroy more homes and challenges firefighters amid steep terrain.

This blog is to introduce some basic knowledge about wildfire, including causes and global map of wildfire. If you want to know more about wildfire, please scroll down!

#1 What is Wildfire and Wildfire season

According to World Health Organization(WHO)， a wildfire is an unplanned fire that burns in a natural area such as a forest, grassland, or prairie. Wildfires are often caused by human activity or a natural phenomenon such as lightning, and they can happen at any time or anywhere. In 50% of wildfires recorded, it is not known how they started.

Wildfire season is the range between what is typically the season’s first large fire to the season’s last. Wildfires are most prevalent in summer. In the early 1950s, wildfire season was typically five months long. As time has gone on and climate change has intensified, our current wildfire season has grown to seven months.

#2 Causes of Wildfire

Wildfires are caused when conditions are hot and dry. Regionally speaking, spring and winter are known to be damper and rainier or snowier in the Midwest, which is why there are minimal wildfires during this season compared to other regions. If we look at Northern California, their wetter seasons tend to be fall and winter, which is why you can find more wildfires there in the summer and spring.

• Nature and Wildfire

Some wildfires in the U.S. Northwest Territories are the result of lightning. Lightning-caused fires are a natural part of the ecosystem and are the primary source of natural disturbance and natural disturbance is required to maintain healthy forests. Without fire, forests would grow old and decadent, losing their capacity to support wildlife and increasing their susceptibility to other less desirable sources of disturbance, such as pest outbreaks.

Lightning can strike almost anywhere (up to 15 kilometers from a storm cell) so fires started by them may not be affected by rain from thunderclouds. Dry lightning can also occur and is a strong ignition source because there is not enough moisture with the storm to interfere with ignition or fire spread.

In Colorado, lightning accounts for only 15 percent of wildfires, with human ignitions accounting for the remainder (Colorado Natural Hazards Mitigation Plan, 2013). Human causes vary and can include escaped debris pile burning, campfires, fireworks, construction sparks, downed transmission lines, and arson.

• Wildfires and Human Behavior

Nearly 85 percent of wildfires in the United States are caused by humans. Human-caused fires result from campfires left unattended, the burning of debris, equipment use and malfunctions, negligently discarded cigarettes, and intentional acts of arson. (Date based on Wildfire Management Information (WFMI) and U.S. Forest Service Research Data Archive)

According to a press release, researchers from the University of Colorado, Boulder’s Earth Lab took a deep dive into the U.S. Forest Service’s Fire Program Analysis-Fire Occurrence Database, analyzing all wildfires recorded between 1992 and 2012. The researchers found that humans caused more than 1.2 million of the 1.5 million blazes in the database. Equipment use causes 11 percent of fires, while campfires and children playing with fireworks or matches each cause 5 percent of fires. The Fourth of July, predictably, is the biggest day for wildfires, with 7,762 fires ignited on that date over the 21-year study period.

# 3 Global Wildfire Map

• Wildfire in North America

According to data from the National Interagency Fire Center, in July 2022 nearly 90 large wildfires and complexes have burned 3,100,941 acres in 12 states. Six new large wildfires were reported, two in Alaska and one in Alabama, Idaho, Montana, and Oklahoma. More than 6,600 wildland firefighters and support personnel are assigned to incidents across the country. Critical weather conditions are expected in parts of the Great Basin, northern Rocky Mountains, and high plains of Nebraska and South Dakota in August 2022.

A report in Canada's National Observer showed several parts of Northern Canada are enveloped in smoke from wildfires along with unusually high seasonal temperatures. More wildfires tend to occur in British Columbia Province as well as the Boreal forest areas of the Canadian Prairies Region, Ontario and Quebec provinces, Northwest Territories, and Yukon Territory. Yukon has seen a huge leap in the number of blazes with just over 846 square kilometers of land scorched this year, while heat warnings and air quality statements are in effect in the Northwest Territories and part of Nunavut.

• Wildfires in Europe

As Western Europe enters its second heat wave in July 2022 the maximum temperatures are predicted to set records. Further south in Europe, in southwest France on Saturday there were temperature peaks of close to 108℉(42℃), as the city of Biarritz broke a maximum temperature record. Nearly three-quarters of the country’s population, 45 million people, were affected by red or orange heat alerts in what is the earliest heat wave ever recorded in France.

The hot, dry weather has resulted in numerous wildfires in Britain, Spain, Portugal, and France over the last several days, bringing an earlier than usual start of the fire season. Firefighters in London, yes, London, have dealt with more than 800 vegetation fires from the start of last month to July 12.

Two blazes near the coastal town of Arcachon in France’s southwest Gironde region have burned more than 24,000 acres since Tuesday. About 3,000 firefighters assisted by firefighting aircraft are battling the blazes in southern France.

Spain is also working on several large fires that have burned tens of thousands of acres. In southern Andalusia, 3,000 people were evacuated after a fire started near the village of Mijas in the province of Malaga.

Around 200 firefighters supported by 18 aircraft are assigned to the incident. According to the data provided by EFFI (European Forest Fire Information System), it shows that the overall number of wildfires in Europe from January to July 2022 is higher than the average of the same period from 2012 to 2021, and some months even exceeded the highest value of the past decade, and the danger of wildfires brought by this heat wave in Europe should not be underestimated.

No matter where you are remember to stay away from areas where there may be wildfires, wildfire season is upon us be safe and protect yourself at all times!