https://cdn.earthdata.nasa.gov/conduit/upload/5182/KeywordsCommunityGuide_Baseline_v1_SIGNED_FINAL.pdf draft 2025-07-25 https://gcmd.earthdata.nasa.gov/KeywordViewer/scheme/projects/885f9438-23f7-4433-b02e-d74305e8bdb9 AASE Date=2026-02-05 User Id=tstevens User Note=updated definition AASE Mission Overview: NASA addressed the crucial scientific issue of global ozone depletion. A major airborne campaign was planned and executed in August and September 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 human’s growing influence on the environment, NASA launched a follow-on experiment to the one conducted over the Antarctic. The second major aircraft-campaign occurred in January-February 1989. The Ozone Trends Panel Report published found that the largest decrease in total ozone occurred during January-February at latitudes near the edge of the Arctic vortex. This experiment investigated the Arctic polar stratosphere from a base in Norway. The primary objectives of the 1989 Airborne Arctic Stratospheric Expedition (AASE) 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 (STEP) and the Airborne Antarctic Ozone Expedition (AAOE). The instruments were flown in these earlier experiments to address the objectives defined for the Arctic Ozone Expedition. The field experiment lasted approximately 7-8 weeks from the last week of December 1988 through the middle of February 1989. The time period allowed measurements during the statistically most active period for the formation of Polar Stratospheric Clouds in the Arctic. The DC-8 was deployed at the same time period as the ER-2, with the data from the two aircraft being complementary. Due to its limited range, the ER-2 was not able to survey the entire Arctic region of interest, whereas the greater range of the DC-8 enabled it to survey the polar vortex and air processed through the cold temperature region of the polar vortex. 2026-02-05T13:13:52.407Z