A tinder-dry Southeast, baked by abnormally high temperatures and mired in drought, has burst into a series of deadly and destructive wildfires, including a recent one that has already killed at least three people near Gatlinburg, Tenn.
From Kentucky and Tennessee across the Carolinas to Georgia and Virginia, the National Interagency Fire Center reports 15 large wildfires that had burned at least 155,000 acres as of Tuesday. Several fires have been burning since late October, and the big one in Tennessee is among four new large fires reported by the National Interagency Fire Center.
Now being called the Chimney Top fire, it has destroyed hundreds of structures and for a time was threatening downtown Gatlinburg. The intense surge of fire activity came after weeks of drought and unusually warm temperatures across the region. The Tennessee fires have burned at least 15,000 acres in Great Smoky Mountains National Park, the nation's most visited national park, which was closed as of late Tuesday.
The long drought in the Southeast left dead leaves, grass and underbrush in the forests of the Southern Appalachian Mountains tinder-dry and ready to burn with the slightest spark, said U.S. Forest Service scientist Jeff Prestemon.
"Certainly since I started studying this in 1990, I've not seen this before, this many large fires burning at the same time. But the regional data are incomplete, so it's really hard for me to say that this is unprecedented," he said.
With the world headed for what will likely be its warmest year ever, topping last year's record, the Southeast has followed that trend with its second-warmest January through October on record, according to the National Centers for Environmental Information (NCEI), which said that both Carolinas are also having their warmest period on record.
The cost of the fires burning into bustling tourism and resort communities like Gatlinburg and Pigeon Forge will easily run into tens of millions of dollars and there are widespread human health impacts from choking smoke, Prestemon said. Much of the region has been under air quality alerts for the past several weeks. Outside of Texas, the Southeast suffered the highest number of billion-dollar weather and climate-related disasters between 1980 and 2012, according to the National Climate Assessment.
The National Drought Monitor shows some level of drought across 73 percent of the Southeast, affecting 24 million people, with several areas suffering through extreme drought. Average temperatures at many weather stations in the region have been ranging from 5 to 15 degrees above normal for several weeks, and some sites have not seen any measurable precipitation for more than a month.
According to the Southeast Regional Climate Center, drought conditions have prevailed across parts of the region since early May. In many locations, no measurable precipitation was recorded on 70 to 80 percent of the days during this period.
Climate change is expected to bring more extreme droughts, and while scientists work to explain the exact ties between global warming and any particular drought, people are left to deal with the impacts.
"The question is, is this a new normal?" said North Carolina forest researcher James Vose. "That's when you start looking at projections into the future, and that's a tricky one.
"The one thing that the models do seem to converge on is that dry periods will become drier and last longer, and wet periods become wetter and more extreme. If the predictions for climate change models play out, these kind of weather patterns that led to these fires will become more common. We've had droughts here before, we've had fires here before, but this is a pretty rare event due to a combination of factors."
According to Prestemon, projections of future wildfire activity in the region are still unclear because climate scientists aren't sure if the Southeast will become wetter or drier. But it will definitely be warmer. In a recent study with other researchers, he concluded that the annual acreage burned by wildfires will increase by 4 percent across the Southeast by mid-century, but there are wide geographic variations within the region.
"But the temperature increase is pretty well settled. Temperatures are rising, and will rise inexorably," he said. "The precipitation changes are an open question. With more research we'll get a better handle on whether these kinds of extraordinary patterns happen more often or less often."
In western North America, the wildfire season has lengthened by more than two months since the 1970s and the average amount of annual acreage burned has increased steadily.
This year's fire season started in January, where bushfires burned 235,000 acres in the Australian island of Tasmania. Those fires destroyed parts of rare forest ecosystems in a vast World Heritage area. A few months later, the Fort McMurray Fire burned about 1.5 million acres between May 1 and July 5 around the tar sands fields of Alberta, Canada.
Alaska had its second biggest wildfire season on record in 2015, and the Indonesia fires in the autumn of 2015 emitted more greenhouse gases than the entire U.S. economy on a daily basis, according to the World Resources Institute. Australia and Siberia have also seen record wildfire seasons in recent years.