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/a075e942-cfbd-4d7e-ac7c-9f031e7cb782 SPADE Date=2026-02-05 User Id=tstevens User Note=updated definition The Stratospheric Photochemistry Aerosols and Dynamics Expedition (SPADE) is the first in a series of field experiments designed to support the NASA High-Speed Research Program (HSRP). This program was designed to assess the impact of emissions from supersonic aircraft operating in the lower stratosphere. SPADE was tasked with determining the key chemical processes that affect ozone levels in the stratosphere. A variety of chemical measurements were made from NASA’s ER-2 high-altitude aircraft based at the NASA Ames Research Center. These measurements were used to address the fundamental reactions between various chemicals in the stratosphere. 2026-02-05T12:58:17.027Z