Air pollution increases the melting of Arctic ice
Whilst increased human-induced emissions of long-lived greenhouse gases (GHGs) are certainly the main driving factor, air pollutants, such as aerosols and ozone, are also important.
Already, significant warming trends have been observed in the Arctic. Future increases in pollutant emissions locally or in midlatitudes could further accelerate global warming in the Arctic.
Air pollutants are transported to the Arctic, most notably from Eurasia, leading to high concentrations in winter/spring (Arctic Haze). Local ship emissions and summertime boreal forest fires may also be important pollution sources.
Aerosols and ozone are perturbing the radiative budget of the Arctic through processes specific to the region:
- absorption of solar radiation by aerosols is enhanced by highly reflective snow and ice surfaces
- deposition of light absorbing aerosols on snow or ice can decrease surface albedo
- tropospheric ozone forcing is more efficient in the dry Arctic winter