Infrastructure protectionSeeping Arctic methane to pose serious problems for Florida coastline
Large quantities of methane gas are buried under the Arctic permafrost; the melting of ice caps in the Arctic causes this gas to escape into the atmosphere through vents; until recently, cryosphere (frozen soil and ice) has served to plug or block these vents, but thawing conditions have allowed the conduits to open, and deep geologic methane now escapes; methane is a very strong greenhouse gas, and its presence in the atmosphere has grown three times faster than carbon dioxide since the industrial era
Melting Arctic permafrost // Source: tehrantimes.com
The ancient reserves of methane gas seeping from the melting Arctic ice cap told Jeff Chanton and fellow researchers what they already knew: As the permafrost thaws, there is a release of methane, a powerful greenhouse gas that causes climate warming.
The trick was figuring out how much, said Chanton, the John W. Winchester Professor of Oceanography at Florida State University.
A Florida State University release reports that the four-member team — whose findings were published in the respected journal Nature Geoscience — documented a large number of gas seep sites in the Arctic where permafrost is thawing and glaciers receding (they found seventy-seven previously undocumented seep sites, comprising 150,000 vents to the atmosphere). Until recently, the cryosphere (frozen soil and ice) has served to plug or block these vents. Thawing conditions, however, have allowed the conduits to open, and deep geologic methane now escapes.
The team studied the link between natural gas seepage and the melting ice cap, using aerial photos and field data to figure out the number — and location — of seep holes.
What is the relationship between methane gas in the arctic and Florida? The more the ice cap melts, the more methane is released into the atmosphere — and the more the climate warms. The more the climate warms, the higher sea levels rise. Chanton and his team of researchers believe coastal areas in Florida could be severely affected by this problem within the next 50 to 100 years.
People who live in coastal areas of Florida could be directly affected, said Chanton, who analyzed the methane and dated it to more than 40,000 years old. All this seeping methane causes more melting ice, Chanton said, which causes sea levels to rise and could affect coastal real estate values —sooner rather than later.
“Methane is a very strong greenhouse gas that’s grown three times faster than carbon dioxide since the industrial era,” Chanton said. “As the Arctic warms, the ice caps melt and the fissures open, so methane escapes and causes more warming.”
This phenomenon causes sea levels to rise, which is particularly problematic in Florida: “Along the flat Florida coastline, a 1-foot rise in sea level could cause anywhere from 10 to 100 feet of shoreline retreat — erosion,” Chanton said. “For us here in Florida, this is really important because we can expect the coast to recede.”
That beach house, he warned, might be in peril: “It may not be there for your grandchildren.”
— Read more in Katey M. Walter Anthony et al., “Geologic methane seeps along boundaries of Arctic permafrost thaw and melting glaciers,” Nature Geoscience (20 May 2012) (doi:10.1038/ngeo1480)
