On local and long-range transported air pollution in Svalbard

Abstract

Climate change, health of the residents and ecosystems in the Arctic region are impacted by local and long-range transported air pollution. Local emissions in the Arctic are important, but overlooked issue. Despite there have been extensive modelling and measurement studies of long-range transport of short-lived climate forcers to Svalbard, the effect of local emissions from diesel and coal power plants and ship traffic on the concentrations of these compounds in major settlements has not been investigated thoroughly. The scope of this work is to study temporal and spatial evolution of air pollutant concentrations in Svalbard using the historical chemical and meteorological data collected in Ny-Ålesund and newly obtained observations from three sites: Ny-Ålesund, Longyearbyen and Barentsburg. Remote and local emission sources, concentrations of anthropogenic short-lived climate forcers and environmental factors that promote long-range transportation and accumulation of local air pollution in the Svalbard settlements have been investigated. A strong seasonality in the concentrations of sulphur dioxide (SO2), nitrogen oxides (NOx), tropospheric ozone (O3) and black carbon (BC) in Svalbard has been observed. Measurements in Ny-Ålesund revealed that in autumn, winter and spring the concentrations of SO2, sulphate and particles of accumulation mode are dominated by the long-range transport of air pollution from remote and regional sources. In summer, the long-range transport of air pollution is limited, and local sources become more important. Indeed, ship traffic emissions in Longyearbyen and Ny-Ålesund promoted significant increase in SO2 and NOx concentrations and slight decrease of the O3 values. Measurements in Barentsburg revealed strong temporarily deterioration of local air quality because of adverse weather conditions promoting transport of polluted air from the local coal power plant to the town. The cases of enhanced accumulation of local ground-level pollution have been revealed in Longyearbyen as well. They have often coincided with long-range transport events when the advection of warm air from mid-latitudes to Svalbard promoted creation of strong temperature inversions and led to increased concentrations of BC detected by the ground-based instrument and in the vertical profiles below 1000 m.