Residence time and spatial variability for gases in the atmosphere

Abstract

The relation between spatial variability and residence time for gases in the atmosphere is studiedusing a two-dimensional numerical model. Results indicate that although the residence timeshows a strong dependence on the variability, other factors, mainly the distribution of sources, also play an important role. If nothing is known about the location of the sources and sinks, theuncertainty in the estimate of the residence time from variability measures will be at least a factorof 10. The situation is greatly improved when one has indications of where the source is located.

Verification of the model, usink: gases in the atmosphere for which variability estimates andindependent estimates of the residence time were available, proved difficult because of theuncertainties associated with thest: estimates. The general features of decreasing variability withincreasing residence time and a strong dependence on the source configuration were, however, confirmed.