This paper studies the interannual variability of pollution pathways from northern hemisphere (NH) conti-nents into the Arctic. Using a 15-year model simulation of the dispersion of passive tracers representative of anthro-pogenic emissions from NH continents, we show that the North Atlantic Oscillation (NAO) exerts a strong control on the pollution transport into the Arctic, particularly in win-ter and spring. For tracer lifetimes of 5 (30) days, surface concentrations in the Arctic winter are enhanced by about 70% (30%) during high phases of the NAO (in the following referred to as NAO +) compared to its low phases (NAO −). This is mainly due to great differences in the pathways of European pollution during NAO + and NAO − phases, respec-tively, but reinforced by North American pollution, which is also enhanced in the Arctic during NAO + phases. In con-trast, Asian pollution in the Arctic does not significantly de-pend on the NAO phase. The model results are confirmed us-ing remotely-sensed NO 2 vertical atmospheric columns ob-tained from seven years of satellite measurements, which show enhanced northward NO 2 transport and reduced NO 2 outflow into the North Atlantic from Central Europe during NAO + phases. Surface measurements of carbon monoxide (CO) and black carbon at high-latitude stations further cor-roborate the overall picture of enhanced Arctic pollution lev-els during NAO + phases.
Mendeley saves you time finding and organizing research
Choose a citation style from the tabs below