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Atmospheric gravity waves (AGWs) are among the important energy and momentum transfer mechanisms from the troposphere to the middle and upper atmosphere. Despite their understood importance in governing the structure and dynamics of these regions, mesospheric AGWs remain poorly measured globally, and largely unconstrained in numerical models. Since late 2011, the Suomi National Polar-orbiting Partnership (NPP) Visible/Infrared Imaging Radiometer Suite (VIIRS) day–night band (DNB) has observed global AGWs near the mesopause by virtue of its sensitivity to weak emissions of the OH* Meinel bands. The wave features, detectable at 0.75 km spatial resolution across its 3000 km imagery swath, are often confused by the upwelling emission of city lights and clouds reflecting downwelling nightglow. The Ionosphere, Mesosphere, upper Atmosphere and Plasmasphere (IMAP)/ Visible and near-Infrared Spectral Imager (VISI) O2 band, an independent measure of the AGW structures in nightglow based on the International Space Station (ISS) during 2012–2015, contains much less noise from the lower atmosphere. However, VISI offers much coarser resolution of 14–16 km and a narrower swath width of 600 km. Here, we present preliminary results of comparisons between VIIRS/DNB and VISI observations of AGWs, focusing on several concentric AGW events excited by the thunderstorms over Eastern Asia in August 2013. The comparisons point toward suggested improvements for future spaceborne airglow sensor designs targeting AGWs.
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High‐Spatial Resolution Space‐Based Observations in the Upper Troposphere and Upper Mesosphere of Wavelike Features Produced by Hurricane Ian
Abstract A new high‐spatial resolution camera on the International Space Station used OH nightglow in the H‐band to image the ground at an 70 m pixel footprint over an 280 km swath and maintained this resolution during its 1.5 s exposure. Near 0405 UT on 28 September 2022 moon down images obtained over the eyewall of the category 4 Hurricane Ian revealed short‐horizontal wavelength (5 km) instabilities with even finer scale (1–2 km) perpendicular structures, similar to those identified in recent modeling. Images taken (10 s apart) are used to separate these tropospheric features from atmospheric gravity waves (AGWs) imaged at 87 km. Geostationary Operational Environmental Satellite 16 (GOES‐16) data were used to estimate the altitudes of the tropospheric features. Available auxiliary data were used to show that the AGWs plausibly originated from close to Ian's eyewall 1–2 hr earlier.
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- Award ID(s):
- 2334173
- PAR ID:
- 10642714
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 52
- Issue:
- 19
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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