Forty people have died and many more are missing in a series of wildfires that have swept across California's Napa Valley this week. At least fifteen fires are still burning across the northern part of the state, where over 890 square kilometres of farmland and 5700 buildings have been destroyed. More than 10 000 firefighters from California and neighbouring states are currently fighting the fires.
Fires burning in Peters Canyon Regional Park in Orange County, California, earlier this week. Irfan Khan/Los Angeles Times.
The worst of this fires is in Sonoma County, where an incident named the Nuns Fire, started by a downed power line hitting tree, has destroyed almost 200 square kilometres of land have been burned and the outskirts of the cities of Sonoma and Santa Rosa affected, and a second incident, the Tubbs Fire, so called because it started near Tubbs Lane near the city of Calistoga has destroyed over 140 square kilometres of land between Calistoga and Sonoma, resulting in 22 deaths.
Burning buildings to the east of Healdsburg in Sonoma County earlier this week. J Morris/San Francisco Chronicle.
In Mendocino County a fire named the Redwood Fire has destroyed around 130 square kilometers of land and destroyed around 90 buildings. Eight people are understood to hav edied on the first day of this fire, prompting the evacuation of a further 5000 from homes in its path. A further six people have died and a further 76 are missing in Napa County, where a blaze called the Atlas Fire has destroyed around 200 square kilometers of land, including much of the county's winelands. In Yuba County four people have died in the Cascade Fire, which has destroyed around 40 square kilometres of land.
The remains of the Signorello Estate Winery in Napa County, California, destroyed by wildfires this week. Justin Sullivan/Getty Images.
The fires have a variety of causes and have been fueled by dry winds blowing from the mountains in the northeast of the state, but are essentially due to a prolonged drought in the state, which has been experiencing dry conditions since 2011, the longest such drought in the state's recorded history. This drought has killed vegetation, including thousands of trees, across much of central California, providing dry tinder to fuel the fires, despite high rainfall that caused flooding in parts of the state in the winter of 2016-7. The draught has been made worse by the diversion of water to suit Human purposes, such as agriculture, industry and leasure, which has taken water away from other ecosystems, resulting in the build-up of dead, dry vegetation that has produced fuel for the fires.
Dry vegetation near Shandon in San Luis Obispo County, California, in May 2015. Al Seib/Los Angeles Times.
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