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AASE
AASE Mission Overview NASA is addressing the crucial scientific issue of global ozone depletion. A major airborne campaign was planned and executed in August and September of 1987 to study the sudden and unanticipated decrease observed in the abundance of ozone over Antarctica in the Austral spring since 1979. Results from that study have provided data which directly implicate man-made chemical compounds, chlorofluorocarbons, in the enormous ozone loss over this remote region in the southern hemisphere. To continue the study of the production and loss mechanisms for ozone in the polar stratosphere and to assess man's growing influence on his environment, NASA is planning a follow-on experiment to the one conducted over the Antarctic. A second major aircraft-campaign is planned for January - February 1989. The recently published Ozone Trends Panel Report found that the largest decreases in total ozone occurred during January-February at latitudes near the edge of the Arctic vortex. This experiment! will investigate the Arctic polar stratosphere from a base in Norway. Objectives The primary objectives of the 1989 Airborne Arctic Stratospheric Expedition are: To study the production and loss mechanisms of ozone in the north polar stratospheric environment. To study the effect on ozone distribution of the Arctic polar vortex and of the cold temperatures associated with the formation of Polar Stratospheric Clouds (PSC's). Approach The Upper Atmospheric Research Program sponsored by the NASA Office of Space Science and Applications has supported the development of instrumentation specifically designed to measure trace species critical to the understanding of stratospheric photochemistry and dynamics. This airborne instrumentation has been flown in two previous experiments: the Stratosphere-Troposphere Exchange Project and the Airborne Antarctic Ozone Experiment. We propose to use the suite of instruments flown in these earlier experiments to address the objectives defined for the Arctic Ozone Expedition. We propose to operate the ER-2 out of Stavanger, Norway (59 N, 5 degrees 38"E). We are planning 10 missions, each with a duration of 7 hours, allowing a range of about 20 degrees of latitude. The field experiment will last approximately 7-8 weeks from the last week of December 1988 through the middle of February 1989. This time period should allow us to make measurements during the statistically most active period for the formation of Polar Stratospheric Clouds in the Arctic. The DC-8 will be deployed for the same period of time as the ER-2, and while most of the flights will be closely coordinated with those of the ER-2, many flights will be quite independent. The data from the two aircraft will be complementary. Because of its limited range, the ER-2 will not be able to survey the entire Arctic region of interest, whereas the greater range of the DC-8 will enable it to survey the polar vortex and air processed through the cold temperature region of the polar vortex. The number of flights would be comparable to those of the ER-2; the prime operating site the same as the ER-2: Stavanger, Norway. METEOROLOGICALLY GUIDED FLIGHT TRACKS In addition to normal weather forecast products to aid in flight planning from the scientific point of view, the mission will have available forecasts of air parcel trajectories and potential vorticity maps, which can be used to follow the movement of air masses of interest, and to define the vortex dynamics. For more information, link to http://cloud1.arc.nasa.gov/aase/