Long-term Variations in Wintertime Arctic Frontal Positions and Their Mercury Anthropogenic Emission Impacts

• Main Author: Wang, Danhan
• Format: Text
• Language: unknown
• Published: Digital Commons @ ESF 2020
• Subjects: Arctic front; Arctic dome; Anthropogenic emission; Mercury; Interannual variation; Environmental Indicators and Impact Assessment; Environmental Monitoring; Arctic; Climate change
• Online Access: https://digitalcommons.esf.edu/etds/200; https://digitalcommons.esf.edu/cgi/viewcontent.cgi?article=1199&context=etds

Wintertime Arctic frontal positions are particularly important in determining the inclusion of mercury emissions from anthropogenic sources in the Arctic. Using the streamline confluence method, the 30-year average positions of wintertime (November-March) Arctic fronts exhibited similar spatial variability (39°N-67°N) over North America and Eurasia during 1988-2017 with considerable interannual variations up to 10° year-to-year shifts in latitude. The long-term variations in Arctic frontal positions partly superseded the impact of the decreasing North American anthropogenic mercury emissions by up to 30%, leading to no significantly detectable emission trend in the North American Arctic. The northward shifts in Arctic frontal positions in some winters in Eurasia have counteracted the impacts of anthropogenic emission changes by 5.3%. This is the first study to examine and quantify the impact of long-term variations in Arctic frontal positions on Arctic anthropogenic mercury emissions; it provides insight into the impact of climate change on Arctic anthropogenic emissions.