CAIRT FL2S case-study results of major stratospheric warming 2019

Results of the Fast Level-2 Simulator (FL2S) of CAIRT developed within the Earth Explorer 11 Phase 0 Science and Requirements Consolidation Study (SciReC) and the Phase A Mission Performance and Requirement Consolidation (PerReC) activities. The scenario corresponds to the dynamically perturbed 2019 Northern hemisphere (NH) winter. That winter was characterized by a major stratospheric warming event in January, followed by strongly enhanced polar mesospheric descent and the formation of an elevated stratopause in the recovery phase. The scenario is based on an extended Whole Atmosphere Community Climate Model (WACCM-X) simulation with a verticalextension from the ground to the exobase and generated by nudging WACCM-X to Modern-Era Retrospective analysis for Research and Applications Version 2 (MERRA-2) reanalysis data up to about 45 km altitude. The specific scenario dataset is based on interpolating from the model’s native cubed-sphere grid ( 25 km resolution) to a 0.25°× 0.25° horizontal grid and interpolated from model levels to equidistant 1 km vertical grid in the altitude range of 0 to 200 km. We used a reduced dataset of 1.5 hours duration on 18 February 2019, 0:00–1:30 UT. It contains all CAIRT L2 targets and has the necessary high time resolution (5 min) to resolve atmospheric variabilitydown to minute scale.