The impact of Arctic circulation on trace gas mesurements at Alert, Canada (scientific paper)

• Main Authors: Trivett,N. B. A., Higuchi,K., Yuen C. W., Worthy,D. E. J.
• Format: Report
• Language: English
• Published: Carbon Cycle Research Section, Air Quality Branch, Atmospheric Environment Service/Carbon Cycle Research Section, Air Quality Branch, Atmospheric Environment Service/Carbon Cycle Research Section, Air Quality Branch, Atmospheric Environment Service/Carbon Cycle Research Section, Air Quality Branch, Atmospheric Environment Service 1996
• Subjects: Arctic; Ellesmere Island; Canada; Memoirs of National Institute of Polar Research; Polar Research; Siberia
• Online Access: https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=2281; http://id.nii.ac.jp/1291/00002281/; https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=2281&item_no=1&attribute_id=18&file_no=1

The Canadian Baseline Observatory at Alert (82°28′N, 62°30′W) is situated at the northern tip of Ellesmere Island in the high arctic. It is the most northerly station in the WMO GAW network. Apart from the local camp, which is sectored out, the nearest major source region for anthropogenic material is over 2500km away, over the pole to northern Russia. Correlations of positive deviations from the modelled time series curves of measured values with 5 day back trajectories confirm that the short term variations in the concentrations of carbon dioxide and methane are due to long range transport of material from the temperate regions of Eurasia. To obtain a quantitative understanding of the relationship between the physical processes of long range tracer transport from the industrial emissions in Eurasia and the magnitude and duration of tracer gas measurement anomalies over the Canadian Arctic, a series of simulations using a regional atmospheric dynamical model is carried out to reproduce specific events of positive CO_2 anomalies observed at Alert. These simulations identify various distinctive tracer transport pathways from Eurasia to the Canadian Arctic. These pathways can be categorized into 3 distinctive groups : (1) direct transport pathway, (2) transport via northern Siberia, across the pole, and (3) recirculation of Arctic air mass.