edu.ucar.opensky::articles:27297 UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact 2025-12-24T18:46:25.965639 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) https://n2t.org/ark:/85065/d7db8635 Impact of the Polar Vortex on Sub-Seasonal O/N 2 Variability in the Lower Thermosphere Using GOLD and WACCM-X 2024-06-21T00:00:00Z publication https://n2t.org/ark:/85065/d7db8635 https://doi.org/10.1029/2024JA032724 Martinez, B. C. author Lu, X. author Pedatella, N. M. author Wu, H. author Oberheide, J. author UCAR/NCAR - Library publisher We provide observational evidence that the stability of the stratospheric Polar vortex (PV) is a significant driver of sub-seasonal variability in the thermosphere during geomagnetically quiet times when the PV is anomalously strong or weak. We find strong positive correlations between the Northern Annular Mode (NAM) index and subseasonal (10-90 days) Global Observations of the Limb and Disk (GOLD) O/N-2 perturbations at low to mid-northern latitudes, with a largest value of +0.55 at similar to 30.0 degrees N when anomalously strong or weak (NAM >2.5 or < -2.1) vortex times are considered. Strong agreement for O/N-2 variability and O/N-2-NAM correlations is found between GOLD observations and the Whole Atmosphere Community Climate Model with thermosphere-ionosphere eXtension (WACCM-X) simulations, which is then used to delineate the global distribution of O/N-2-NAM correlations. We find negative correlations between subseasonal variability in WACCM-X O/N-2 and NAM at high northern and southern latitudes (as large as -0.54 at similar to 60.0 degrees S during anomalous vortex times). These correlations suggest that PV driven upwelling at low latitudes is accompanied by corresponding downwelling at high latitudes in the lower thermosphere (similar to 80-120 km), which is confirmed using calculations of residual mean meridional circulation from WACCM-X. UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact PDF Text theme Resource Type 2016-01-01T00:00:00Z publication Copyright author(s). This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. None eng geoscientificInformation