Atmospheric Gravity Wave Derived from the Neutral Wind with 5-Minute Resolution Routinely Retrieved by the Meteor Radar at Mohe

Abstract

Atmospheric gravity waves (GWs) in the mesosphere-lower thermosphere (MLT) are crucial for the understanding of general circulation. However, their dynamical characteristics are hardly retrieved due to the difficulty in the high-resolution observation of wind. Therefore, this paper uses eight years (2013–2020) of meteor radar measurements in the MLT region at Mohe station (53.5, 122.3), China, to retrieve high-temporal-resolution mesospheric wind data and further evaluate the temporal variation of GW kinetic energy. As the detected meteor trails exceed 6, the wind velocity is recalculated using the least square algorithm method, significantly increasing the temporal resolution of wind from 1 h up to 5 min. This resolution is sufficiently high for the investigation of GW kinetic energy, which exhibits a high spatial-temporal variability. For instance, it is enhanced in the winter season during the period of 0200–1400 UT and in the spring season during the period of 0800–1300 UT. The similarity between the climatological characteristics of GWs in MLT and the seasonal variation of GW total energy in the troposphere, determined from high-resolution radiosondes near to Mohe station, suggests that the meteorology in the lower atmosphere could be an important source of GWs in the MLT region.

Sub-Hourly Variations of Wind Shear in the Mesosphere-Lower Thermosphere as Observed by the China Meteor Radar Chain

“…N denotes the meteor counts in a certain height/time bin. This method is also mentioned in Long et al [58].…”

“…In our recent studies, as outlined in Long et al [58], the extraction of GW kinetic energy in the MLT region employs the broad spectral method, which will be explained in more detail later. The perturbations of the wind field are derived by removing the background states (u 0 , v 0 ) that are estimated by a polynomial fit from the meteor winds [61][62][63][64].…”

Mesospheric tide comparisons at low latitudes observed by two collocated meteor radars

“…Meteor radars operate around the clock, regardless of day or night, and function effectively under geographic conditions, allowing for robust long-term observations. Consequently, meteor radars have proven to be a potent technology for researching the dynamics and climate of the middle atmospheric region, including aspects like wind fields (Yi W et al, 2019;Gu SY et al, 2021;Stober et al, 2021;Zhou BZ et al, 2022;Long C et al, 2023), neutral density (Takahashi et al, 2002;Stober et al, 2014), temperature (Hocking, 1999;Hall et al, 2012), planetary waves (Kishore et al, 2018;Wang JC et al, 2021;He MS and Forbes, 2022) and tidal waves (Jacobi et al, 2017;He MS and Chau, 2019;Spargo et al, 2019;Liu GP et al, 2022).…”