Is Methane The Cause Of Past Ice Age Global Warming?
By studying gas bubbles frozen in ancient Greenland ice, University of Victoria researchers have dispelled a popular theory that marine gas hydrates caused a significant release of methane gas into the Earth’s atmosphere, triggering a period of global warming at the end of the last ice age. “Understanding the behaviour of global atmospheric methane is important because it’s the third strongest greenhouse gas after carbon dioxide and water vapour,” says biogeochemist Dr. Michael Whiticar, part of the Canada-U.S. team that conducted the study. “Atmospheric methane concentrations have increased about 250 per cent in the last 250 years, and they continue to rise about one per cent a year.” Methane in the Earth’s atmosphere is an important greenhouse gas with a global warming potential of 25 over a 100-year period. This means that a methane emission will have 25 times the impact on temperature of a carbon dioxide emission of the same mass over the following 100 years. Methane has a large ef
