Sunday, 9 February 2003
Analysis of Seasonal and Diurnal Trends in Surface Ozone Concentration at Arctic Sites (Summit/Greenland and Barrow/Alaska)
Tropospheric ozone (O3) is one of the most important atmospheric constituents. It is fundamental in determining oxidation processes in the atmosphere. It also serves as a major greenhouse gas, thus playing a key role in the energy balance of the atmosphere. Some recent research has revealed springtime ozone depletion at Arctic Sites. This evidence shows that the interaction of atmospheric gases and the Polar snowpack are linked by some photochemical processes. Previous measurements made at Summit, Greenland have demonstrated that ozone is rapidly destroyed in surface snow during periods of solar irradiance. In this study, temporal and spatial changes in surface ozone from Summit, Greenland and Barrow, Alaska were studied. The goal of this project was to better understand ozone depletion and its dependence on photochemical processes in the snowpacks. The diurnal and seasonal changes in surface ozone concentration and their dependence on solar radiation and meteorological parameters were investigated. The comparison of data from Barrow and Summit gave new insight into how surface ozone is influenced by proximity to the ocean, altitude, and solar radiation. Ozone depletion during the period of polar sunrise is a consistent phenomenon at coastal locations, whereas at Summit, opposite seasonal cycles with spring maxima are observed.