HAO Colloquium - McArthur Jones Jr, NRL

Nudging the TIME-GCM with NAVGEM: Initial results and future steps

During the past two decades, and especially during the most recent solar minimum period, there has been a paradigm shift from a mainly solar forced ionosphere-thermosphere (IT) system to an IT system that is also subject to persistent meteorological forcing via a spectrum of different wave components. Considerable progress has been made in modeling lower atmospheric drivers of the IT, but the mechanisms that connect the mesosphere, thermosphere, and ionosphere are still poorly understood, particularly on time scales of months to years. To address this, the overarching goal of our study is to uncover the links that connect the mesospheric composition to the F-region ionosphere. To accomplish this goal we have performed numerical experiments using the National Center for Atmospheric Research (NCAR) Thermosphere-Ionosphere-Mesosphere-Electrodynamics General Circulation Model (TIME-GCM) nudged by 3-hourly Navy Global Environmental Model (NAVGEM) analyses (i.e., winds and temperatures) in the stratosphere and mesosphere, and examine the consequences for the seasonal and intra-annual variations in the thermosphere and F-region ionosphere. In this seminar, we show preliminary results from a January-March 2010 TIME-GCM simulation designed as a proof-of-concept in order to assess the nudged TIME-GCM’s capability in reproducing a sudden stratospheric warming (SSW) in late January/early Feburary 2010 and compare our initial results with TIMED (Thermosphere Ionosphere Mesosphere Energetics and Dynamics) SABER (Sounding of the Atmosphere using Broadband Emission Radiometry) atomic oxygen near 97 km, GUVI (Global Ultraviolet Imager) O/N2 ratios, and available ionospheric profile measurements.

Date and time: 
Wednesday, May 24, 2017 - 1:30pm to 2:30pm