@article{oai:nipr.repo.nii.ac.jp:00002469, author = {Stauffer,Bernhard and Fluckiger,Jacqueline and Monnin,Eric and Nakazawa ,Takakiyo and Aoki ,Shuji}, journal = {Memoirs of National Institute of Polar Research. Special issue}, month = {Mar}, note = {P(論文), Air in polar ice has about the same composition as atmospheric air at the time of ice formation. This allows to determine the composition, especially the concentration of greenhouse gases, in the past. However, the air composition in the ice can be slightly altered by chemical and biological processes in the ice. The reliability of long term trends can be determined by comparing records from different ice cores. For short duration details and time lags such comparisons are not possible due to uncertainties of the age scales of records from different cores. In this case very detailed records along sections of ice cores show whether the scatter of the results is larger than the theoretical expected one. A larger scatter is assumed to be caused by reactions between impurities in the ice which show generally short term variations. A low scatter of detailed high resolution records is therefore, a prerequisite for reliable records.}, pages = {139--152}, title = {Discussion of the reliability of CO2, CH4 and N2O records from polar ice cores (scientific paper)}, volume = {57}, year = {2003} }