Northern California is under a siege of wildfires and smoke, fueled by drought and heat made worse by human-caused climate change, and the list of cities and towns under evacuation orders is long. The Caldor Fire continued its rapid expansion Wednesday, growing at double the pace of firefighters’ models from roughly 30,000 acres on Tuesday to 62,586 acres Wednesday night. The even larger “megafires,” Dixie, McFarland, and Monument, have also continued growing.

The Dixie Fire has incinerated an additional 66,000 acres since Monday, becoming the first known fire in state history to burn all the way from the western slopes of the Sierra Nevadas, across the mountains, and into the eastern valley floor. As the fires roar through tinder-dry fuel, they are wiping out forests central to California’s plans to reduce the state’s carbon emissions, and filling the air with hazardous pollution.

Resources stretched thin

The fact that 30 fire engines and their firefighters were moved from the Dixie Fire to fight the Caldor Fire illustrates just how thin firefighting resources are stretched, due in part to the widespread conflagrations burning across the continent. (“Canada is burning as well,” Cal Fire director Thom Porter told the Sacramento Bee.) Though still much smaller, the exceptionally fast-burning Cache Fire destroyed dozens of homes and threatened an elementary school, forcing children to hurriedly flee as flames burned just across the street. Reaction to the fire near Clearlake was initially limited, officials said, because some local crews were already deployed to assist in fighting the Caldor Fire.

The extended drought and recent heat, both made worse by climate change, have created conditions ripe for the exceptionally destructive fires. “It’s important for all Californians to understand the severity of how our climate-driven conditions are altering the environment and are making these fires move faster and making them more complex and, ultimately, more dangerous than anything we’ve faced in the past,” Mark Ghilarducci, director of the emergency services office, told reporters.

(Fires: Washington Post $, AP, New York Times $, Axios, NBC; Caldor Fire growth: Washington Post $, SFGATE, Sacramento Bee $, San Francisco Chronicle $, ABC, CBS, Washington Post $; Dixie Fire: San Francisco Chronicle $, The Hill; Carbon emissions: AP; Air quality: New York Times $, Sacramento Bee $; Limited resources: Sacramento Bee $; Cache Fire: San Francisco Chronicle $, ABC-7; Climate Signals background: 2021 Western wildfire season, Drought)