ATMOSPHERIC ENVIRONMENT SERVICE DOWNSVIEW (ONTARIO)
An examination of detrended atmospheric C02 time series from two arctic monitoring stations, Alert and Mould Bay, shows a very prominent seasonal cycle with a very broad maximum in the winter and a very sharp minimum in the late summer. The amplitude of the cycle is about 15 to 16 ppmv parts per million by volume. This seasonal cycle is a reflection of the metabolic cycle of the land biota in the northern hemisphere. During the period of broad maximum concentration in winter, the time series of C02 shows, in some years, a bimodal feature, with a relative minimum in late winter. The bimodal distribution is difficult to explain in terms of 1 photosynthetic respiratory cycle of terrestrial biospheric activities in the middle latitudes, and 2 anthropogenic activities. In this paper, we will speculate and discuss the bimodal feature in terms of the evolution of the atmospheric circulation in the Arctic.
This article is from 'Proceedings of the International Conference on the Role of the Polar Regions in Global Change Held in Fairbanks, Alaska on 11-15 June 990. Volume 2', AD-A253 028, p412-415. See also Volume 1, AD-A253 027.