Northern hemisphere concentrations of methane and nitrous oxide since 1800: Results from the Mt. Logan and 20D ice cores

• Published in: Chemosphere
• Main Authors: Dibb, Jack E., Rasmussen, R A, Mayewski, Paul A, Holdsworth, G
• Format: Text
• Language: unknown
• Published: University of New Hampshire Scholars' Repository 1993
• Subjects: Atmospheric Sciences; Yukon; Greenland; Greenland ice cores; ice core
• Online Access: https://scholars.unh.edu/earthsci_facpub/156; https://doi.org/10.1016/0045-6535(93)90263-5

Concentrations of CH4 and N2O have been determined in bubbles extracted from the Mt. Logan (Yukon) and 20D (south Greenland) ice cores. The enclosure dates of the trapped gas samples range from 1802 to 1960; thus these data help to document the anthropogenic increases of these two greenhouse gases in the Northern Hemisphere atmosphere. In general, the new data are in accord with previous ice core studies showing accelerating increases in concentration of both gases since 1900. The Mt. Logan records appear to be the first for any trace gases from alpine glacial ice. The present data set is too sparse to be conclusive, but suggests generally higher CH4concentrations over south Greenland than Mt. Logan, particularly for the 1850 - 1900 period.