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Title: Thermospheric Energy and Heating Due To Upward Propagating and in Situ Generated Tides During Solar Cycle 24
Abstract We investigate vertical and horizontal energy transport and associated heating in the thermosphere due to both upward propagating and in situ generated migrating and nonmigrating diurnal and semidiurnal tides over the solar cycle 24 (2009–2019). Upward propagating tidal fields are derived from wind and temperature observations from the TIDI and SABER instruments onboard the TIMED satellite, utilizing the Hough Mode Extension (HME) fitting approach. Using these observational tidal fields and fluid dynamic equations, we characterize both vertical and horizontal wave energy fluxes in the 80–250 km altitude range, providing a detailed view of how tidal energy varies throughout the thermosphere. Corresponding thermospheric heating rates are also derived from the observed tidal fields. To assess the contribution of in situ generated thermospheric tides to tidal energy and heat budget, we employ the same approach to the Specified Dynamics Whole Atmosphere Community Climate Model with thermosphere‐ionosphere eXtension (SD‐WACCM‐X) simulations for the same period and find that in situ generated tidal energy flux dominates the upper thermosphere. Our results reveal the temporal evolution of tidal energy fluxes across solar activity levels, as well as the complex interplay between vertical and horizontal energy redistribution, identifying regions of tidal energy sources and sinks. These findings improve our understanding of tidal energy transport in determining the dynamics and energetics in very low Earth orbit, the new frontier of space operations.  more » « less
Award ID(s):
2149695
PAR ID:
10680082
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
AGU Wiley
Date Published:
Journal Name:
Journal of Geophysical Research: Space Physics
Volume:
131
Issue:
3
ISSN:
2169-9380
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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