Earths Cracks May Contribute to Global Warming

Michael Reilly, Discovery News

Feb. 19, 2009 -- Whether devastating faults, dank caves or mud cracks on a drying desert plain, Earth's surface is riddled with fractures. Now a new study had found that the cracks exhale large quantities of gas, perhaps enough to affect global warming.

Noam Weisbrod of Ben Gurion University of the Negev and a team of researchers monitored a crack about 2 meters long (6.5 feet) and 1 meter (3.3 feet) deep for two years in the Negev Desert is Israel. Each night, they watched as warm air in the crack drew water vapor out of the surrounding rock, and lifted it into the cold evening air.

If air in the crack is just 7 degrees warmer than the ambient temperature, it is buoyant enough to rise out of any crack in the ground bigger than 1 centimeter (0.4 inch) across, bringing with it any gases that leak out of the surrounding soil or rock.

But the team was surprised to find that the crack they studied gave off water vapor up to 200 times faster than areas without fractures.