This is a collaborative proposal by Principal Investigators from the Oregon State University and Pennsylvania State University. During this project, they will evaluate trends, mechanisms and sources of atmospheric methane loading through the Holocene. Their approach will include a detailed sampling of previously recovered ice cores from Greenland and modeling experiments to document long-term trends in the Holocene as well as during critical periods such as the early Holocene, the 8.2 ka event, the last 5,000 years (a period of proposed anthropogenic input), and the last 200 years. The use of specific methane isotopes, modeling, and comparison of interpolar gradients through time will allow more accurate determination of sources and causes of atmospheric methane concentrations archived in polar ice cores. This further analysis of the interpolar methane gradient, presumably controlled by larger northern hemisphere sources, is anticipated to shed light on changing methane sources through the Holocene.
