Scientific objectives

Key issues adressed by POLSTRACC are:

• Improving the understanding of chemical and physical processes involved in polar ozone loss
• Detailed investigation of structure and composition of the climate-sensitive UTLS region at high latitudes with focus on the LMS region, the direct interface between stratosphere and tropopause
• Investigation of the outflow of the Arctic polar vortex into the LMS region, subsequent transport to lower latitudes and mixing with extra-vortex air
• Improving the knowledge on the properties of polar stratospheric clouds (PSCs) and vertical redistribution of nitrogen-containing compounds by PSC particles into the lower stratosphere
• Investigation of the role of Arctic cirrus clouds affecting the chemical composition and radiative budget of the Arctic UTLS
• Monitoring of the spatial and temporal variability of trace constituents and aerosols in the Arctic UTLS region during different phases of the polar winter
• Improving model simulations for the evolution of the ozone layer and the knowledge on the role of the Arctic UTLS region in the climate system