When Bruce Springsteen sang “I’m on fire” in 1984, little did he know that three decades later, his son would be tasked with putting fires out. This year Sam Springsteen and his 1.2 million colleagues in the US Fire Department will likely have their hands full with the West Coast preparing for what could be its potentially worst fire season till date.
Already this year, the California Department of Forestry and Fire Protection (CAL FIRE) is reporting more than 16,000 acres burned across the state. Around the same time last year, that number was 3,600. Drought, increasingly late monsoons and extreme heat conditions have prompted CAL FIRE to predict a harsher and longer fire season than last year, which itself was the worst on record thus far. The forecast is grim. The Pacific Gas and Electric Corporation (PG&E,) California’s largest utility company, has already started preparing for fire season, weeks before they normally would and in a blunt assessment of the situation, California’s Natural Resources Secretary Wade Crowfoot lamented that “we can’t sugar-coat the fact that this summer is going to be challenging.”
Concrete predictions are hard to come by however, as fire depends on both underlying conditions (moisture in the soil and the amount of flammable vegetation, often called ‘fuel’) and random occurrences such as wind events and ‘ignitions’, both human and natural. There are three primary environmental factors that contribute to wildfires, namely, drought, heat and wind. Drought and heat exacerbate fires by drying out the landscape, thus making vegetation more flammable. Wind in turn helps to spread fires and can occasionally cause them as well by knocking down power lines.
What are wildfires?
A wildfire can be defined as any type of uncontrolled fire that spreads across wildland, including pastureland, forests, grasslands and peatlands. Not all wildfires are bad and indigenous populations and forest management departments have long used controlled or prescribed fires to preserve natural lands. Controlled fires are set systematically under optimal weather conditions and can be an essential tool in clearing adapted ecosystems and limiting the amount of dry vegetation in areas prone to wildfires. However, most intentional wildfires are ill-advised because if done incorrectly, they can destroy large parts of forests, displace local ecosystems and in some cases, spiral out of control. Notably, in 1997, a fire set intentionally to clear forest land in Indonesia escalated into one of the largest wildfires in history. Hundreds of people died, millions of acres burned, at-risk species perished from the flames and smoke and haze lingered over Southeast Asia for months, causing acute health conditions.
Globally wildfires have many impacts on humans, wildlife and the economy. Wildfires are responsible for 5-8% of the 3.3 million annual premature deaths from air quality and are a large driver of greenhouse gas emissions. Though fires happen across the globe, the largest and fastest spreading wildfires mostly occur in the grasslands of Australia, Africa and Central Asia according to NASA’s fire datasets. Some researchers estimate that up to 70% of the world’s fires occur on the African continent, largely due to the fact that slash and burn agriculture is a common practice there. In 2019 and 2020, wildfires dominated headlines following high-profile events in Australia, the Arctic, the Amazon and North America.
While fires have been worsening in some regions, globally the total area burned from wildfires has decreased over the past 20 years according to the Global Fire Emissions Database. This is partially because areas like rainforests that are prone to fires are now being converted into agricultural land. However, in regions of the world that are drying out due to global warming, extreme fire seasons have increased in recent years.
California is one such region that has been particularly affected. Before the Americas were colonised, Native Americans deliberately and routinely burned large parts of what is now California land. But as fire suppression techniques improved, the intensity of fires decreased in the short to medium term. Over the decades, this resulted in the build-up of ‘fuel’ causing forests to grow denser and bushier than they were before. This, combined with increasing drought and heat has created an ecosystem ripe for extreme wildfires in the state.
2020 was the worst year on record for California with more than 4 million acres lost to wildfires. No other year dating back to the start of reliable records in 1933, surpassed 2 million acres. The 2020 California wildfires were so intense that they even generated a new term, gigafire, to describe a single blaze burning over a million acres. The impacts of these fires were vast. In addition to the land lost, 31 people and 10% of the world’s redwoods died in the flames, and the smoke generated resulted in an estimated 112 million metric tons of carbon dioxide entering the atmosphere. In context, this is equivalent to the emissions generated by 24.2 million passenger cars driven in a single year according to a calculator from the US Environmental Protection Agency.