edu.ucar.opensky::articles:25344 UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact 2025-12-24T22:45:32.954374 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) https://n2t.org/ark:/85065/d75q50s4 Effects of Subauroral Polarization Streams on the upper thermospheric winds during non-storm time 2022-05-01T00:00:00Z publication https://n2t.org/ark:/85065/d75q50s4 https://doi.org/10.1029/2021JA029988 Zou, Y. author Lyons, L. R. author Shi, Xueling author Liu, J. author Wu, Qian author Conde, M. author Shepherd, S. G. author Mende, S. author Zhang, Y. author Coster, A. author UCAR/NCAR - Library publisher Intense sunward (westward) plasma flows, named Subauroral Polarization Stream (SAPS), have been known to occur equatorward of the electron auroras for decades, yet their effect on the upper thermosphere has not been well understood. On the one hand, the large velocity of SAPS results in large momentum exchange upon each ion-neutral collision. On the other hand, the low plasma density associated with SAPS implies a low ion-neutral collision frequency. We investigate the SAPS effect during non-storm time by utilizing a Scanning Doppler Imager (SDI) for monitoring the upper thermosphere, SuperDARN radars for SAPS, all-sky imagers and DMSP Spectrographic Imager for the auroral oval, and GPS receivers for the total electron content. Our observations suggest that SAPS at times drives substantial (>50 m/s) westward winds at subauroral latitudes in the dusk-midnight sector, but not always. The occurrence of the westward winds varies with AE index, plasma content in the trough, and local time. The latitudinally averaged wind speed varies from 60 to 160 m/s, and is statistically 21% of the plasma. These westward winds also shift to lower latitude with increasing AE and increasing MLT. We do not observe SAPS driving poleward wind surges, neutral temperature enhancements, or acoustic-gravity waves, likely due to the somewhat weak forcing of SAPS during the non-storm time. 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