A 3-dimensional dynamical regional atmospheric model was used to investigate the quantitative relationship between the physical processes of long range CO₂ transport from the emission region in Eurasia, and the magnitude and duration of a CO₂ anomaly measurement over the Canadian Arctic. We chose to simulate a positive CO₂ anomaly episode of about 5ppm observed at Alert, located at the northern tip of Ellesmere Island, during early December of 1990. The simulation allowed us to examine the evolution of the spatial distribution of the CO₂ anomaly field as it was being transported from the emission region in northern Europe to Siberia, and then across the Arctic Ocean to the Canadian Arctic. The anthropogenic CO₂ took more than a week to reach eastern Siberia, and stayed there until a synoptic situation evolved to finally advect it across the pole to the Canadian side.
With the industrial emission from the northern Eurasia as the only CO₂ source, the model was able to simulate an intrusion of a CO₂ anomaly field into the Canadian Arctic of little less than 2ppm. With the inclusion of land biospheric CO₂ sources, the model was able to account for much of the remaining 3ppm.
The positive CO₂ anomaly observed at Alert on December 1 represents a “classical” case of a low-level transport of CO₂ from Eurasia, via northern Siberia, to the Canadian Arctic during a winter season characterized by a very strong inversion in the lower troposphere.