We’re bringing you exclusive content from our newsletter, The Forecast, right here on Medium. Sign up here. This story is from our feature called the Weather Corner, where we take a deep dive into weird weather around the world, from our June 7th, 2021, newsletter.
Nearly three-fourths of the Western U.S. has plunged into the most severe drought in the recorded history of the U.S. Drought Monitor. However, the ongoing drought is now poised to intersect with the region’s upcoming wildfire season, which threatens to exponentially intensify both of these weather phenomena’s impacts.
Wildfire season technically refers to the range between the year’s first large fire through the last; however, it can get a little more complicated than that. Wildfires are more likely to spark and spread when conditions are hot and dry. The West Coast typically experiences a rainy fall and winter, leading to blooming vegetation in the springtime, which slowly dries out during a warm, dry summer. The dry or dead brush becomes kindling for wildfires, sparked by a natural event, such as a lightning strike, or an accidental or intentional human-caused event, such as a downed power line, fireworks, or arson.
Drought creates conditions that make wildfires more dangerous and harder to contain. Less precipitation means that more vegetation is bone-dry and very flammable, plus water reservoirs are lower.
2020 saw the beginning of this current drought (as we’ve written about in newsletters in the past few months) and the West’s worst fire season in recent history.
How climate change adds fuel to the fire
Both droughts and wildfires are a normal part of life in the region and have occurred regularly throughout history — but climate change is worsening the situation. Higher temperatures, an effect of increased greenhouse gases in the atmosphere, mean more evaporation, drying out the moisture trapped in the ground in soils and reducing snowpack, lake and river levels, and groundwater availability.
In California right now, that’s led to state reservoirs clocking in at 50% lower than they should at this time of year, an Associated Press report reported.
Changing climatic conditions also mean altered precipitation circulation patterns, which impact characteristics of storms, such as where they develop and what path they take. For example, the 2020 summer monsoons never arrived in the Southwest, further exacerbating water stress there.
Other factors also worsen wildfires, such as the US’ history of suppressing wildfires, a larger population in the West developing previously untouched nature, and the strong Santa Ana winds, which, each fall, bring dry air from the Great Basin area of the West into Southern California.
With less favorable climate conditions, wildfire season is growing longer: In the early 1950s, it was typically five months long. Now, it’s seven months.
California is an agricultural powerhouse. It’s also a tinderbox.
Both drought and wildfire threaten the region’s booming farm economy and farmworkers. Over a third of vegetables and two-thirds of the fruits and nuts in the entire U.S. are grown in California alone.
The state accounts for over 13% of the nation’s total agricultural value.
Source: The OC Register
As we wrote previously about the close link between agriculture and water in the state:
Modern agriculture in the state began in the 1920s, when farmers began transforming the desert in the middle of the state, known as Central Valley, into verdant crop fields by pumping groundwater to the surface in the 1920s. In the 1970s, California undertook a massive water infrastructure project to deliver water from wetter parts of the state to the Central Valley and elsewhere, relieving some of their reliance on groundwater.
Currently, the state irrigates more than 9 million acres of cropland using roughly 34 million acre-feet of water diverted from rivers, lakes, and reservoirs that brings this water through an extensive network of aqueducts and canals. But it’s not enough anymore.
When these rivers, lakes, and reservoirs aren’t replenished and the state’s agricultural regions enter a drought — which is all happening more frequently, as described above — growers again face net water shortages. They resort back to pumping groundwater, drilling deep underground to pump water from aquifers in order to grow crops and water landscaping (this practice is largely unregulated in the state, so landowners are allowed to pump “reasonable” amounts of groundwater on their property). However, this groundwater depletion leads to the thousands of miles of land sinking.
Source: Interesting Engineers
Drought threatens this fragile system. With even less water available for the agricultural sector, farmers and ranchers face prolonged crop failure and pasture loss. Plus, droughts tend to evaporate water available for irrigation. And on a broad scale, drought, coupled with high temperatures, may expand the distribution and incidence of pests and diseases that affect crops, forage, and livestock.
Wildfires also threaten agricultural products, workers, and communities. They can cause widespread devastation from crops and soil damage to livestock injury and death to countless health risks for agricultural workers. In addition, wildfire smoke and ash, and even the chemicals used to fight fires negatively affect air and water quality.
How stakeholders are taking action
As Oregon’s local newspaper, the Statesman Journal, aptly put it:
There is often good predictive information, in the case of wildfires, including the dryness of fuels, mountain snowpack and temperature and rainfall, both observed and expected. But each season follows its own playbook, heavily influenced by lightning strikes, human-ignited fires and the actual observed weather — none of which can be predicted in advance.
Essentially: we have good weather predictions that describe the conditions a fire will meet. But it’s nearly impossible to predict the spark of a wildfire.
Still, the U.S. Forest Service (USFS) has said that its strategy this year will be to prioritize putting out fires when they’re small before they can grow into megafires like the ones we saw last year. (The USFS is an agency of the U.S. Department of Agriculture that administers the nation’s 154 national forests and 20 national grasslands, which is predominantly in the West. It’s responsible for wildfire management and response on them. In 2020, 70% of the nationwide acreage burned by wildfires was on federal lands, or 7.1 million acres.)
States carry out wildfire prevention and responses on their managed land too. As the Washington state local newspaper, the Kitsap Sun, reported, Washington state is already undergoing preparation efforts, such as prescribed burns and forest thinning. These are a part of the Washington Department of Natural Resources Commissioner Hilary Franz’s plan to boost forest health. These efforts received a cash infusion last year, when the state legislature approved $37 million more to carry out a more aggressive plan to take on the wildland blazes, a $71 million boost for direct wildfire response, like for firefighters, and $20 million for home protection programs over the next two years.
In California, as we wrote previously: “California is responding to its droughts (and by extension, climate change) by passing legislation. In 2015, amid the severe multi-year drought, the state made long-overdue groundwater and sustainable water investments. Many localities implemented water conservation plans, and the federal government provided millions in emergency grants to drought-stricken communities and farmers.”
The state is also planning to have its largest firefighting force in history working on the ground during peak fire season. CNBC reported that Alisha Herring, a communications representative for Cal Fire, said that the department has already completed dozens of fuel reduction projects, including controlled burns, to reduce the threat of fires this season.
Colorado is also already planning legislation for wildfire risk mitigation. The Colorado Recovery Plan aims to protect communities and create jobs, by investing $25 million in targeted wildfire risk mitigation, recovery, and workforce development.
Have any more questions about global weather events, their impacts, and how they’re linked to climate change? Send them to media@climate.ai — we will choose one to answer in the next newsletter.