The wildfires that have swept through the Okefenokee this year are the largest in the lower 48 states in nearly a century. Do they portend a hotter future?
June 13, 2007
The wildfires that have swept through the Okefenokee this year are the LARGEST IN THE LOWER 48 STATES OF THE U.S. IN NEARLY A CENTURY, since 1918. The state sees an average of 8,000 forest and brush fires a year, but the vast majority are doused before they can burn an acre. The typical wildfire can be contained by a single ranger armed with a fire plow. But not the fire that started April 16. High winds toppled a tree into a power line, fanning the resulting sparks to ignite nearby brush left dry by the lack of rain. The same winds then urged the flames deep into the surrounding longleaf and loblolly pine forests. The air itself was arid, with no hint of the humidity that usually accompanies the beginning of the oppressive South Georgia summer. The fire raged through 18,000 acres in its first day – roughly 26 square miles. Two months later, the fire has consumed more than 600,000 acres on both sides of the Georgia/Florida border, including most of the Okefenokee and tens of thousands of acres of commercial pine forests. Commonly referred to as a swamp, the Okefenokee is technically a bog, because its moisture comes from rainwater rather than a spring or river. When there's meager rainfall, as in recent months, the water table drops, drying out the peaty, compostlike soil. After the bog catches fire, it usually continues to burn for a year, spreading underground until all available fuel has been depleted. As global warming continues, the semipermanent high-pressure weather cells covering the planet are expected to expand, with much of the rainfall occurring at the edges of those cells, leaving their cores drier. Since, during summer months, the Southeast is at the center of such a cell – called the Bermuda high – Georgia will gradually, and perhaps irreversibly, lose rainfall to the Northeast and Canada. As the state becomes hotter and drier, wildfires will become more frequent and more intense.