Effect of Small‐Scale Gravity Waves on Polar Mesospheric Clouds Observed From CIPS/AIM

Abstract

Data from the Cloud Imaging and Particle Size experiment on the Aeronomy of Ice in the Mesosphere (AIM) satellite are employed to study the impact of small-scale gravity wave (GW) on albedo, ice water content (IWC), and particle radius (PR) of polar mesospheric clouds. Overall, 23,987 eligible GW events, with a horizontal wavelength of 20-150 km are eventually extracted from Cloud Imaging and Particle Size level 2 orbit albedo maps during 2007-2011. The overall statistical results show that when small-scale GWs travel horizontally in polar mesospheric clouds, they can amplify the albedo and IWC by a rate of 10.0-22.6%, while reducing the PR by as much as À7.01%. Owing to the strong temporal and spatial dependences, the albedo and IWC variations are larger on an average during the core of the season, while they decrease during the initial and final periods of the season. The obvious zonal asymmetries are also found. The albedo variations show a positive linear relation with the GW amplitudes in albedo, as opposed to a negative linear relation with GW horizontal wavelengths. In most of the GW events, the periodic variation in the trend of albedo exhibits an anticorrelation with that of PR. Combining previous research studies with our results, we deduce that the rapid change in particle concentration and the upward movement of water vapor by GWs may be very important aspects for explaining the influence mechanism.

Responses of CIPS/AIM noctilucent clouds to the interplanetary magnetic field

“…The long-term trends in NLCs are thought to be associated with global climate change. NLCs are susceptible to perturbations from loweratmospheric activities such as gravity waves (Gao et al, 2018) and planetary waves (France et al, 2018). NLCs are strongly influenced by both solar and lunar tides, with diurnal and semidiurnal variations observed in the NLC properties (Fiedler and Baumgarten, 2018;Stevens et al, 2017;.…”

The MATS Satellite Mission – Gravity Waves Studies by Mesospheric Airglow/Aerosol Tomography and Spectroscopy

“…The vertical structure of the NLC is strongly determined by the microphysics that governs cloud growth and sedimentation (Rapp and Thomas, 2006). The tomography will provide detailed insights in this vertical NLC evolution, including its possible modification by wave activity (Hultgren and Gumbel, 2014;Megner et al, 2016;Gao et al, 2018). However, since the vertical structure of the narrow NLC layers is dominated by microphysics rather than dynamical processes, a retrieval of vertical wavelengths of gravity waves will not be feasible from the NLC data.…”

Signatures of gravity wave-induced instabilities in balloon lidar soundings of polar mesospheric clouds

“…High-resolution observations of PMC are obtained using both active and passive remote sensing instruments that are based on ground or carried by satellite, aircraft or balloon (e.g. Baumgarten and Fritts, 2014;Gao et al, 2018;Miller et al, 2015;Reimuller et al, 2011;Schäfer et al, 2020). Lidar instruments allow for high vertical resolution down to few meters, revealing various stages in the approach to, or attainment of, gravity wave breaking and other nonlinear dynamics made visible by the PMC layer.…”