Its vegetation then spends much of the summer slowly drying out because of a lack of rainfall and warmer temperatures. That vegetation then serves as kindling for fires. That dries out vegetation even more, making it more likely to burn. But then climate change, in a few different ways, seems to also load the dice toward more fire in the future.
Even if the conditions are right for a wildfire, you still need something or someone to ignite it. Sometimes the trigger is nature, like a lightning strike, but more often than not humans are responsible. Many deadly fires have been started by downed power lines. People are increasingly moving into areas near forests, known as the urban-wildland interface, that are inclined to burn. In recent years, the U.
Each fall, strong gusts known as the Santa Ana winds bring dry air from the Great Basin area of the West into Southern California, said Fengpeng Sun, an assistant professor in the department of geosciences at the University of Missouri-Kansas City.
Sun is a co-author of a study that suggests that California has two distinct fire seasons. One, which runs from June through September and is driven by a combination of warmer and drier weather, is the Western fire season that most people think of.
Those wildfires tend to be more inland, in higher-elevation forests. But Sun and his co-authors also identified a second fire season that runs from October through April and is driven by the Santa Ana winds. But thinning small trees is not always a profitable enterprise—in some cases, ecological thinning projects may cost more to conduct than the timber value they generate. Any material that is cut either must be burned in place or removed and taken somewhere, such as a sawmill or a biomass power plant.
For many forested regions, however, the nearest mill or biomass plant is a long and expensive drive away. The collapse of sawmills is a story for another time. Native tribes have been skillfully burning landscapes in the West for thousands of years to benefit game animals and traditional food and basketry plants, and to maintain an open landscape for travel and protection from wildfires. To many Native peoples, the biggest fire-related risk is the negative effects caused by the absence of fire.
Cultural fire — the skilled, intentional use of fire, led by Native fire practitioners — is critical for preserving many Native communities and cultures and caring for the land.
Although European settlers largely removed Native tribes from most of their lands, some tribes persisted with fire stewardship, and there is now broad recognition among land managers and ecologists that intentionally setting fires can be a critically important forest management tool. Another form of intentional burning, prescribed fires are typically used to achieve ecological objectives e.
Prescribed fire is highly cost-effective for reducing the abundance of woody fuels across large areas of land while providing additional benefits to biodiversity.
Both cultural fire, which follows the leadership of Indigenous fire practitioners, and prescribed fire, which often burns at a larger scale, are essential for addressing the challenges we currently face with fire.
Along with instituting prescribed fire, for about the last 50 years land managers have allowed some wildfires to burn in certain places and under certain conditions. This typically occurs in more remote areas within National Parks and National Forests, far from human settlements, when there is little wind and the fire is not expected to exhibit extreme behavior.
The decision to manage fire, rather than to suppress it, is complicated, incorporating the location, weather conditions, topography, and firefighter availability and safety. Allowing fires to burn can have substantial benefits, such as increasing forest resilience to fire and drought, and reducing the severity of a future wildfire that may occur under more extreme weather conditions.
While there is some risk involved in managed fire — for example if weather conditions change suddenly — managed wildfire is an essential management option for remote areas where prescribed fire or mechanical thinning may not be feasible.
Since almost all landscapes will inevitably burn eventually, allowing fires to burn when conditions are mild can be less risky than a full fire suppression policy. Full fire suppression will eventually fail when extreme fire weather occurs, potentially resulting in less ecologically beneficial fire than a managed fire under mild conditions. The best example of an area with a full return of wildfire is the Illilouette Creek Basin in Yosemite National Park, where almost all lightning-ignited fires have been allowed to burn since the s.
The Illilouette Creek Basin has seen a remarkable increase in biodiversity and water availability, with lessened water stress for trees in the basin and an increase in downstream water flow. There are a variety of ways that you can be engaged, and in our experience, involvement may help stave off feelings of helplessness that creep up as we read the news about fire and see the smoke that settles over us.
Everyone can help by advocating for good fire policies. If you can vote, elect leaders who care about good fire and the protection of the most vulnerable. Reach out to community leaders and legislators to tell them that this is a priority. Advocating for broader use of prescribed fire is one important step anyone can take to help create a future where we have a better relationship with fire. If you live in the wildland-urban interface, you may have some work cut out for you.
Air can absorb about 7 percent more water for every degree Celsius it warms. Abatzoglou noted that some of the harrowing scenes across Northern California in were due to an extreme and unusual dry lightning siege in mid-August that ignited thousands of fires in one night. This is the first part of a story about fires in California. Read part 2 here. Photograph courtesy of InciWeb.
Story by Adam Voiland. View this area in EO Explorer. Heat waves and droughts supercharged by climate change, a century of fire suppression, and fast-growing populations have made large, destructive fires more likely.
Whether sparked by lightning, intentional land-clearing, or human-caused accidents, wildfires are burning longer and more often in some northern latitudes as the world warms. Following a notable increase in fire activity in August and a gradual rise in deforestation, scientists have been watching for signs of how might shape up. Several worrisome signs have emerged.
Image of the Day Land.
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