Comparing EMARS Reanalysis with Independent Observations of the Martian Atmosphere
Open Access
Author:
Woods, Kaylen
Area of Honors:
Meteorology
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
Steven J Greybush, Thesis Supervisor Johannes Verlinde, Thesis Honors Advisor
Keywords:
Mars atmosphere EMARS radio occultation meteorology
Abstract:
The Ensemble Mars Atmosphere Reanalysis System (EMARS), which assimilates Thermal Emission Spectrometer (TES) spacecraft retrievals, is a useful tool for analyzing atmospheric conditions on Mars at hourly intervals on a regular grid, especially in places where there is a lack of spacecraft observations. In order to test the accuracy of this new product, independent observations of the Martian atmosphere were compared to EMARS outputs across several Mars years. A radio science instrument suite hosted aboard Mars Global Surveyor includes radio occultation experiments, which collect data used to retrieve temperature profiles. Comparison of these temperature profiles to interpolated EMARS temperatures yield a consistent negative bias, meaning EMARS overestimates radio occultation temperatures by 4 K to 7 K on average. Areas such as the top and bottom of the atmosphere, high Northern latitudes, winter seasons, and night local times either produced a more negative bias or a larger standard deviation that was of interest to this discussion. This study identifies and explains regions of higher bias which can be used for improvements in future versions of EMARS.
