Improvement, coupling, and validation of the MESORAC-HIAMCM for simulating accurate thermospheric GWs from the most common tropospheric/stratospheric GW sources
Abstract
PROJECT/ABSTRACT#Approved for Public ReleaseResearch Problem and Objectives:Primary atmospheric gravity waves (GWs) are created by deep convection, orographic forcing, the polar vortex jet, and jets and fronts. Most of these GWs break/dissipate in the middle atmosphere/lower thermosphere. GW dissipation results in the deposition of momentum and energy, which unbalances the atmosphere. The atmosphere responds by generating #higher-order# GWs via a process called #multi-step vertical coupling# (MSVC). Recent studies using the nudged HIgh Altitude Mechanistic general Circulation Model (HIAMCM) and the Sami3 is Also a Model of the Ionosphere (SAMI3) have shown that the thermospheric GWs from the polar vortex jet and orographic forcing are higher-order (not primary) GWs, and that the TIDs generated by these higher-order GWs agree well with GNSS data. Therefore, MSVC is an essential component of a successful whole atmosphere model (WATM). Currently, the HIAMCM is the only proven WATM that includes MSVC. In addition, WATMs cannot resolve deep convection. Although most WATMs parameterize GWs from deep convection, this method 1) does not provide an accurate representation of the convective GWs important for the thermosphere and 2) does not include higher-order GWs from deep convection. The Model for gravitywavE SOurce, Ray trAcing and reConstruction (MESORAC) simulates the convectively-generated GWs most important for the mesosphere/thermosphere. A recent study using MESORAC, HIAMCM and SAMI3 calculated the GWs and TIDs generated by the Tonga volcanic eruption. Good agreement was found withICON-MIGHTI and GNSS data worldwide. Although a volcanic eruption is not common, 1) the vertical updrafts are similar to those from deep convection (although with larger scales and amplitudes), and 2) the convective GWs modeled by MESORACagree well with those observed by OH airglow. Therefore, the MESORAC, HIAMCM and SAMI3 likely provide the most accurate simulationsof thermospheric GWs and TIDs from common troposphere/stratosphere GW sources to date. If funded, our research will improve, coupleand validate the MESORAC and HIAMCM,as well as address some significant science questions. Our main objectives are:OB1: Write software to automatically extract convective plume parameters fromsatellite weather data;OB2: Incorporate simplified chemistry for O2, N2, and O into the HIAMCM;OB3: Couple the MESORAC and HIAMCM on NASA Pleiades HPC supercomputer;OB4: Run MESORAC-HIAMCM for targeted quiet-time case studies and compare/validate the results with observations.Technical Approaches: Our methodology involves our in-house MESORAC and HIAMCM models, and publiclyavailabledata from weather satellites, GEOS forecast, ICON-MIGHTI, and the Madrigal CEDAR database. Our team covers the expertise needed to successfully complete this research: PI Vadas developed/runs the MESORAC and Co-I Becker developed/runs the HIAMCM.Anticipated Outcome: Our research will result in 1) a coupled, improved, accurate, and validated WATM whichsimulates the most important quiet-time thermospheric GWs; 2) knowledge about seasonal, local time and latitudinal characteristics of thermospheric GWs; and 3) improved understanding of thevertical coupling from the lower to upper atmosphere via quiet-time GWs.Impact on DoD Capabilities: The MESORAC and HIAMCM are the only models proven to simulate MSVC and the resultingthermospheric GWs from the most common tropospheric/stratospheric primary GW sources on a global scale. Experience with and tools developed for thisadvanced model suite could, in the future, greatly help to improve the predictive capability of the DoD/ONR model #NIMO#, which is an ionospheric forecast model that contains data assimilation and SAMI3 but which does not contain realistic simulations of GWs and MSVC. ONR Code 322MM Program Officers Bruce Fritz and Daniel Eleuterio recently stated this need in a presentation given at the 2023CEDAR workshop.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Nov 08, 2024
- Source ID
- N000142412367
Entities
People
- Sharon L. Vadas
Organizations
- Northwest Research Associates
- Office of Naval Research
- United States Navy