SAN FRANCISCO -- Deadly wildfires in California have burned more than 4 million acres this year - more than double the previous record for the most land burned in a single year in the state.
California fire officials said the state hit the astonishing milestone Sunday with about two months remaining in the fire season. The previous record was set two years ago when wildfires destroyed 1.67 million acres (2,609 square miles).
Flames have scorched an area larger than Connecticut. About 17,000 firefighters are still battling nearly two dozen major blazes throughout the state.
Virtually all the damage has occurred since mid-August, when five of the six largest fires in state history erupted. Lightning strikes caused some of the most devastating blazes. The wildfires have incinerated hundreds of homes and killed 31 people but large parts of them are burning in largely unpopulated land.
Many of the most destructive fires sparked in Northern California, where hills and mountains dotted with many dead trees have provided plenty of fuel for fires igniting amid high temperatures and strong winds fanning the flames. Thick, gray smoke from the blazes has fouled the air in many hill communities and major cities in the San Francisco Bay Area and beyond.
Numerous studies have linked bigger wildfires in America to climate change from the burning of coal, oil and gas. Scientists say climate change has made California much drier, meaning trees and other plants are more flammable.
Fire officials said the Glass Fire burning in wine country for the past week was their top priority.
Three fires, driven by strong winds and high temperatures, merged into one tearing into vineyards and forested mountain areas, including part of the city of Santa Rosa. Thousands of people were under evacuation orders, including the entire population of Calistoga, a town of 5,000.
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