USAP-DC

Recent theoretical and experimental work indicates that in a wide range of altitudes and for periods from a few minutes to several hours, a significant part of the wave activity observed in the thermosphere is due to acoustic gravity waves radiated by infragravity waves in the ocean. It is proposed to study this impressive connection between geospheres in Antarctica, at the location where close proximity of the Ross Ice Shelf makes it very special. Infragravity waves are able to excite the fundamental mode and low-order oscillations in the Ross Ice Shelf at its resonance frequencies, with the latter creating standing wave structures throughout the atmosphere. It is likely that this effect was recently detected using lidar observations at McMurdo. This project will study implications of this phenomenon, as well as more general aspects of wave activity in Antarctic geospheres, using data from a unique combination of recently installed instruments: the Dynasonde at Korean Jang Bogo station, the NSF-sponsored network of seismographs and microbarometers on the Ross Ice Shelf, and the IMS-affiliated infrasound station near McMurdo. The goal of this research is to study atmospheric waves in the thermosphere in Antarctica and to investigate the roles that the Ross Ice Shelf and the Southern Ocean play in generation of the atmospheric waves. Anticipated results are of interest also for general aeronomy and for glaciology. This project will verify the hypothesis that the persistent atmospheric waves in mesosphere and lower thermosphere, which are observed with a lidar instrument at McMurdo, are related to the low-frequency vibration resonances of the Ross Ice Shelf excited by infragravity waves in the ocean. An accurate characterization will be achieved for low-frequency oscillations of the Ross Ice Shelf and the quality factors of its resonances will be assessed. Investigation of a consistency between observed and predicted vertical distributions of the wave intensity is expected to provide insights into where the horizontal momentum carried by AGWs is transferred to the mean motion, i.e., to the large-scale dynamics of the Antarctic thermosphere. A determination of whether accurate measurements of the acoustic resonant frequencies and their variations can provide useful constraints on the neutral temperature profile in the atmosphere will be done. Extensive use of Jang Bogo Dynasonde data in all mentioned tasks will allow further developing Dynasonde techniques.

Person	Role
Godin, Oleg	Co-Investigator
Zabotin, Nikolay	Investigator and contact

Antarctic Astrophysics and Geospace Sciences	Award # 1643119
Antarctic Glaciology	Award # 1643119

USAP-1643119_1

None in the Database

1. Negrea, C., Zabotin, N., & Bullett, T. (2018). Seasonal Variability of the Midlatitude Traveling Ionospheric Disturbances From Wallops Island, VA, Dynasonde Data: Evidence of a Semiannual Variation. Journal of Geophysical Research: Space Physics, 123(6), 5047–5054. (doi:10.1029/2017ja025164)
2. Moral, A. C., Kaymaz, Z., Kalafatoglu Eyigüler, E. C., Zabotin, N., & Livingston, R. (2020). First results from ITU-Dynasonde, Istanbul, Turkey on the ionospheric characteristics. Advances in Space Research, 66(11), 2537–2555. (doi:10.1016/j.asr.2020.08.034)
3. Helmboldt, J. F., & Zabotin, N. (2022). An Observed Trend Between Mid‐Latitudes Km‐Scale Irregularities and Medium‐Scale Traveling Ionospheric Disturbances. Radio Science, 57(5). Portico. (doi:10.1029/2021rs007396)