@article{766973215f8f4a479edfd695cecba582,
title = "Validation of ICON-MIGHTI Thermospheric Wind Observations: 2. Green-Line Comparisons to Specular Meteor Radars",
abstract = "We compare coincident thermospheric neutral wind observations made by the Michelson Interferometer for Global High-Resolution Thermospheric Imaging (MIGHTI) on the Ionospheric Connection Explorer (ICON) spacecraft, and four ground-based specular meteor radars (SMRs). Using the green-line MIGHTI channel, we analyze 1158 coincidences between Dec 2019 and May 2020 in the altitude range from 94 to 104 km where the observations overlap. We find that the two datasets are strongly correlated (r = 0.82) with a small mean difference (4.5 m/s). Although this agreement is good, an analysis of known error sources (e.g., shot noise, calibration errors, and analysis assumptions) can only account for about a quarter of the disagreement variance. The unexplained variance is 27.8% of the total signal variance and could be caused by unknown errors. However, based on an analysis of the spatial and temporal averaging of the two measurement modalities, we suggest that some of the disagreement is likely caused by temporal variability of the wind on scales ≲70 min. The observed magnitudes agree well during the night, but during the day, MIGHTI observes 16%–25% faster winds than the SMRs. This remains unresolved but is similar in certain ways to previous SMR-satellite comparisons.",
keywords = "ICON, MIGHTI, ground-space comparison, neutral wind, thermosphere",
author = "Harding, {Brian J.} and Chau, {Jorge L.} and Maosheng He and Englert, {Christoph R.} and Harlander, {John M.} and Marr, {Kenneth D.} and Makela, {Jonathan J.} and Matthias Clahsen and Guozhu Li and Ratnam, {M. Venkat} and {Bhaskar Rao}, {S. Vijaya} and Wu, {Yen Jung J.} and England, {Scott L.} and Immel, {Thomas J.}",
note = "Funding Information: The line of sight winds and metadata from all 1158 MIGHTI‐SMR coincidences are archived on Zenodo ( http://doi.org/10.5281/zenodo.4050607 ). This analysis used v03 of the Level 2.1 ICON‐MIGHTI data, which is available from the ICON website ( https://icon.ssl.berkeley.edu/Data ) and will soon be available at the Space Physics Data Facility ( https://spdf.gsfc.nasa.gov/ ). The Ledong, Wuhan, and Beijing meteor radars are supported by the NSFC (41727803), the Solar‐Terrestrial Environment Research Network of Chinese Academy of Sciences, and the Chinese Meridian Project. The meteor wind data from Ledong, Wuhan and Beijing are archived at the Data Center for Geophysics ( http://wdc.geophys.ac.cn/ ), National Earth System Science Data Sharing Infrastructure at BNOSE, IGGCAS. The Tirupati meteor radar data set used here is available on Zenodo ( https://doi.org/10.5281/zenodo.4433180 ). Funding Information: The authors are grateful to the broader ICON team. ICON is supported by NASA's Explorers Program through contracts NNG12FA45 C and NNG12FA42I. The participation of J. L. Chau and M. He in this work is part of the project supported by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under SPP 1788 (DynamicEarth)‐CH 1482/1‐2 (DYNAMITE2). Publisher Copyright: {\textcopyright} 2021. American Geophysical Union. All Rights Reserved.",
year = "2021",
month = mar,
doi = "10.1029/2020JA028947",
language = "English (US)",
volume = "126",
journal = "Journal of Geophysical Research: Space Physics",
issn = "2169-9380",
number = "3",
}