S.C. Forestry Commission bulldozer at fire (copy)

A specially equipped enclosed-cab bulldozer creates a firebreak around a wildfire in this undated photo. S.C. Forestry Commission/Provided

A national report on the country's future climate paints a dire picture for the Southeast, including South Carolina, which in addition to increased coastal flooding is expected to see a more aggressive wildfire season, sharp risks to human health and steep economic losses. 

A warming world, driven by emissions of greenhouse gasses that trap heat in the atmosphere, is already leading to sea level rise, which has become increasingly noticeable in low-lying coastal areas like Charleston. 

In addition to flooding, the Southeast should expect more frequent fires as droughts worsen and lengthen, according to the fourth National Climate Assessment, a report mandated by Congress and released by President Donald Trump's administration Friday. The work is the effort of 13 federal agencies. 

For this region, it's not simply a matter of bearing down and dealing with hotter, more volatile weather.

Because the Southeast is a "transition zone," a region between tropical and temperate climates, it will be smacked harder than other regions, the report said. The finding echoes earlier reports and studies.

Already the impacts of climate change have arrived as gradually rising seas have helped make high-tide flooding a regular nuisance that can snarl traffic and trash properties around Charleston.

The vast majority of scientists who study the issue agree the steady rise in average global temperatures is due to the gasses that are released when fossil fuels are burned. Researchers say average temperatures have risen enough that some impacts from global warming are unavoidable. 

But the severity of effects felt around the world depend on future emissions. 

"It's already bad but it can get worse, and the sooner we act, the more likely we are to avoid the worst of what might happen," said Kirsten Dow, a USC professor and one of the authors of the report's section on the Southeast. "So it’s definitely not time to give up." 

A fiercer fire season

As temperatures rise and droughts persist longer, fires could become a more regular part of life.

"In the future, rising temperatures and increases in the duration and intensity of drought are expected to increase wildfire occurrence and also reduce the effectiveness of prescribed fire," the report said. 

South Carolina already has a fire season, roughly from late fall to the spring. It's not nearly as intense as in the West, where California's Camp Fire was only contained Sunday after killing dozens of people and destroying thousands of homes. 

Historically, fires have been an important part of the ecosystem, said Darryl Jones, fire chief for the S.C. Forestry Commission. They are crucial to species like the red-cockaded woodpecker or the Venus flytrap.

Forestry officials use prescribed burns to improve habitat for those species and others. The management technique is also crucial to stopping huge, unmanageable fires because it eats up fuel on the forest floor that might feed a full-on inferno in drier situations, Jones said. 

"When we do a prescribed burn now, we’re trying to mimic that pattern that used to happen hundreds of years ago," he said.

Managing forests well doesn't just decrease the likelihood of fires, said Doug Wood, a spokesman for the forestry commission. Forests can function as carbon "sinks," as trees intake carbon dioxide and release oxygen during photosynthesis. 

"Trees are the ultimate carbon storage machines," Wood said.

In 2009, South Carolina saw its biggest wildfire in more than three decades. The Horry County blaze burned a path 4 miles wide and 6 miles long, destroyed dozens of homes and forced about 2,500 residents to evacuate. No one was killed.

Risk to economies, security 

In both its effects on human health and infrastructure, climate change has the potential to suck money out of the economy of the Southeast. 

Shipping hubs like the port of Charleston will be threatened as the adjacent infrastructure needed to move goods through the coast is threatened by flooding and sea level rise. Flood events are already costly — the report estimates the damage from Hurricane Florence in early October at $2.1 billion.

On top of the infrastructure damage, national security is threatened, because the coast is home to several key military bases.

"This report reinforces what the U.S. military and the intelligence community have been telling us for years," said Frank Femia, the Center for Climate and Security co-founder and a chief executive officer. "Climate change presents a serious risk to both our military and our overall national security."

Among the biggest potential economic drags are those that stem from worsening human health. Rising temperatures threaten industries that depend on outdoor work, such as agriculture. 

That means the region could lose a half a billion labor hours by the end of the century. 

"The South is disproportionately getting those lost labor impacts," Dow said. "You’re going to have more occupational injuries and you’re going to need to do more to make sure people have adequate cooling time during the day."

Under the worst emissions scenarios, increased temperatures could cost the Southeast $47 billion in lost labor annually. 

A warmer climate also means that tropical, disease-carrying species, like the Aedes aegypti mosquito, will march north, increasing the incidence of diseases such as dengue fever. 

The pace 'is much faster'

Climate change threatens to make the diverse ecosystems of the Southeast less livable. 

Familiar animal and plant species will disappear. Fewer and different species will take over — something South Carolina already is seeing with cogongrass and the armadillo. Growing crops will get harder, as will managing forests and waters.

"As a result, the ecological resources that people depend on for livelihood protection and well-being are increasingly at risk, and future generations can expect to experience and interact with natural systems that are much different than those that we see today," the report said.

The report cites the extreme rainfall and flooding that South Carolina already is experiencing, with heavy rainfall events doubling by the end of this century. During the worst storms, 20 percent more rain will fall than does now.

The record-breaking rains and flooding from Florence came with the state still reeling from three years and hundreds of millions of dollars of flooding and damage spurred by hurricanes or tropical storms.

Warming seas already are disrupting marine species including food fish. Coral bleaching, long considered a tropical threat, has been found on reefs offshore.

Meanwhile, the region's cycles of rain and drought spells will worsen. Stronger, slower hurricanes and rising seas will worsen flooding. The seas will swamp coastal marshes that are invaluable sea-life and seafood nurseries. Saltwater will move inland, making it more difficult to handle wastewater disposal.

While some ecosystems will adapt readily, others will change drastically, especially in the places where wetlands give way to open ocean, said Adam Terando, another author of the report. 

"Our wetlands and estuaries, they also have a very large adaptive capacity, but the pace of the change, that’s much faster than these ecosystems have really been used to (dealing) with," he said. 

Reach Chloe Johnson at 843-735-9985. Follow her on Twitter @_ChloeAJ.

Science and environment reporter. Author of Washing Our Hands in the Clouds.