ATD Observer

ATD Observer, https://opensky.ucar.edu/solr-search/content?field_member_of=all&search_api_fulltext=%22atd%20observer%22&sort_by=search_api_relevance&sort_order=DESC&items_per_page=10&f%5B0%5D=date_range%3A%28min%3A1990%2Cmax%3A1993%29. National Center for Atmospheric Research (NCAR) Archives. https://aspace.archives.ucar.edu/repositories/2/digital_objects/4849 Accessed April 21, 2026.