USA– This years catastrophic wildfire season — with more than 7.6 million acres already burned — could be just a glimpse at what the future holds.
The risk of so-called very large wildfires could increase as much as six times in the U.S. by mid-century as a result of man-made global warming, researchers concluded in a study announced by the National Oceanic and Atmospheric Administration on Wednesday.
Very large fires are defined as the top 10% of fires based on acreage. Such blazes account for the majority of burned acres across the U.S. each year. There are currently 66 large fires burning, a step down from very large.
Climate change is expected to both intensify fire-friendly weather conditions such as heat and drought — and lengthen the season during which these fires tend to spread, according to the study, which was published in the International Journal of Wildland Fire.
Huge sections of the western U.S. would see the risk of very large fires increase by as much as 200% to 500%. The highest risk area includes the Great Basin and Northern Rockies, as well as the Sierra Nevada and Northern California.
Scientists in the study used computer models to simulate future climate conditions, based on projections of greenhouse gas emissions from the continued burning of fossil fuels such as coal, oil and gas.
Over the past couple of decades, wildfires have charred more and more of the U.S. Nine of the 10 years with the largest number of acres burned on record have occurred since 2000, according to the National Interagency Fire Center.
Several states, including Washington, Colorado, New Mexico, Texas and Oregon have all seen their largest or most destructive wildfires on record in this decade alone.
A separate study out Wednesday from NASA and several universities showcased global warming’s opposite concern: Increased risk of coastal flooding due to higher-than-predicted sea-level rise by 2100.
Given what we know now about how the ocean expands as it warms and how ice sheets and glaciers are adding water to the seas, its pretty certain we are locked into at least three feet of sea level rise, and probably more, said Steve Nerem of the University of Colorado, Boulder, and leader of NASA’s Sea Level Change Team.
Previously, the Intergovernmental Panel on Climate Change estimated a one-to-three-feet sea-level rise by the end of the century, so NASA’s study is on the highest end of that prediction.
Heat-trapping greenhouse gases from the burning of fossil fuels are causing more glaciers and ice sheets in Greenland and Antarctica to melt. The process causes the water to expand, because warmer water takes up more space than cooler water.
Globally, sea level has risen about eight inches since the beginning of the 20th century and more than two inches in the last 20 years alone.
The higher sea levels will lead to flooding of coastal cities around the world, both due to tidal cycles and storm surges from ocean storms. U.S. cities at risk include Miami, Norfolk, New Orleans and New York.