Study On The Upper Atmosphere Of Venus At The Terminator
Abstract
Observations have been made using the SOIR instrument aboard the Venus Express (VEx) mission characterizing the temperature and carbon dioxide profiles at the terminators. Using the Venus Thermospheric General Circulation Model (VTGCM), these profiles can also be modeled at the terminators for many latitudes. For this research, the SOIR and VTGCM profiles are averaged in the following northern latitude bins; 0-30, 30-60, 70-80, 80-90. Using the data from SOIR and outputs from the VTGCM, one can determine how well the current model reproduces the observations at the terminator. In the current VTGCM model, the temperature maximum and minimums characteristic of the data profiles are the same if not very similar with the exception of the magnitude of these characteristic features. The SOIR data tends to reveal more extreme maximum and minimum temperatures as compared to the simulated VTGCM values. Some assumptions made in the data processing technique used to determine the SOIR profile retrievals may not be valid. This causes temperatures around 125 km and above 140 km to not be as accurately represented. VTGCM thermal balance plots help address this problem. In addition, these balances provide insight as to why the model may not be in complete agreement with these SOIR profiles while also determining any missing physical processes that are not included in the current VTGCM framework. Data-model comparisons will also be considered for variable VTGCM parameters, including solar minimum and moderate fluxes as well as extremes of the wave drag parameter yielding minimum and maximum terminator winds. Using the VTGCM model in correspondence with data collected from the SOIR instrument, this study will characterize the overall climate at the Venus terminators and give insight into the physical mechanisms responsible.
- Publication:
-
AAS/Division for Planetary Sciences Meeting Abstracts #44
- Pub Date:
- October 2012
- Bibcode:
- 2012DPS....4441604F