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. 2019 Nov;6(2):137-150.
doi: 10.1002/gdj3.77. Epub 2019 Aug 23.

The Ensemble Mars Atmosphere Reanalysis System (EMARS) Version 1.0

Steven J Greybush  1   2   3 , Eugenia Kalnay  3 , R John Wilson  4 , Ross N Hoffman  5 , Thomas Nehrkorn  5 , Mark Leidner  5 , Janusz Eluszkiewicz  5 , Hartzel E Gillespie  1 , Matthew Wespetal  3 , Yongjing Zhao  3 , Matthew Hoffman  6 , Patrick Dudas  2 , Timothy McConnochie  7 , Armin Kleinböhl  8 , David Kass  8 , Daniel McCleese  9 , Takemasa Miyoshi  3   10
Affiliations

The Ensemble Mars Atmosphere Reanalysis System (EMARS) Version 1.0

Steven J Greybush et al. Geosci Data J. 2019 Nov.

Abstract

The Ensemble Mars Atmosphere Reanalysis System (EMARS) dataset version 1.0 contains hourly gridded atmospheric variables for the planet Mars, spanning Mars Year (MY) 24 through 33 (1999 through 2017). A reanalysis represents the best estimate of the state of the atmosphere by combining observations that are sparse in space and time with a dynamical model and weighting them by their uncertainties. EMARS uses the Local Ensemble Transform Kalman Filter (LETKF) for data assimilation with the GFDL/NASA Mars Global Climate Model (MGCM). Observations that are assimilated include the Thermal Emission Spectrometer (TES) and Mars Climate Sounder (MCS) temperature retrievals. The dataset includes gridded fields of temperature, wind, surface pressure, as well as dust, water ice, CO2 surface ice and other atmospheric quantities. Reanalyses are useful for both science and engineering studies, including investigations of transient eddies, the polar vortex, thermal tides and dust storms, and during spacecraft operations.

Keywords: assimilation; atmosphere; ensemble; mars; reanalysis.

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Figures

Figure 1
Figure 1
Plot of observation availability for TES and MCS by Mars Year and Ls. Counts are number of temperature superobservations, given on a logarithmic (base 10) scale
Figure 2
Figure 2
Sample screenshot from the EMARS plotter
Figure 3
Figure 3
Sample screenshot from the EMARS animator depicting transient eddy temperature (colours), surface pressure (black contours; solid for positive, dashed for negative) and wind (vectors) anomalies
See this image and copyright information in PMC

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