The Scientific Committee on Solar-Terrestrial Physics (SCOSTEP) / Predictability of the variable solar-terrestrial coupling (PRESTO) is hosting online seminars to deliver the latest scientific topics and/or instructive review presentations on solar-terrestrial physics related to SCOSTEP’s PRESTO program. This online seminar is organized with the support of the Institute for Space-Earth Environmental Research (ISEE), Nagoya University, Japan. The seminar details with recordings will also be available at this link.
This online seminar titled: “It’s YES for NO, O/N2 and e: Perturbative and transport effects by gravity waves in the mesosphere, thermosphere and ionosphere” and will feature Dr. Hanli Liu a senior scientist at the High Altitude Observatory, NCAR, USA.
Abstract
WACCM-X (Whole Atmosphere Community Climate Model with thermosphere/ionosphere extension) shows significance biases in representing several key constituents in the middle and upper atmosphere, including nitric oxide (NO) in the mesosphere and lower thermosphere (MLT), the O/N2 in the thermosphere, and the plasma density in the ionosphere F-region. These biases are thought to be related to transport, though the exact causes are not well understood.
Moreover, perturbative effects of the gravity waves are not accounted for in current parameterization schemes, but they are known to be important for processes in the middle and upper atmosphere, for example temperature dependent chemical reactions, traveling atmospheric/ionospheric disturbances (TADs/TIDs), and ionospheric irregularities. These challenges motivate the development of the high-resolution (HR) capability of WACCM-X, and in this study the HR simulation results are examined.
The resolved gravity waves and characteristics of TIDs from the HR simulations compare well with available observations in the middle and upper atmosphere. MLT NO, column integrated O/N2 and F-region plasma density show overall improvements. By analysing the high-resolution simulation results and comparing with control simulations at regular resolution, the effects of the resolved gravity waves is elucidated on the transport from the MLT to the upper thermosphere, by altering both mean circulation and wave mixing.