The first paper describing our newest climate model for Mars has just gone live at the journal Icarus as a paper-in-press.  You can access the paper here.  The model simulates the global Martian atmosphere – but unlike all prior full general circulation models for Mars (Mars GCM), it does so with a novel numerical approach and a novel (cube-sphere) computational grid.  The upshot of the improved numerics is much better treatment of things like dust and water vapour that are blown around in the atmosphere.  As the crucial elements of the Martian climate system, getting the transport of these systems right is central to proper simulation of the climate.  In the paper, we “calibrate” the model with Mars Odyssey Orbiter Gamma Ray / Neutron Spectrometer and Mars Exploration Rover Alpha Proton X-ray Spectrometer measurements of argon.  Argon is a really useful “tracer” as it has no chemical or physical sources or sinks – it is merely enriched or diluted by “freeze distillation” of the CO2 that makes up the majority of the Martian atmosphere.  The good news is that the new model does much better than all prior Mars GCMs.  The bad news is that the model still under-predicts argon in the southern polar winter.  There’s still obviously work to be done before we properly understand transport in the Martian atmosphere.

As with the WRF model that we also run at Ashima Research, the core MITgcm is primarily used for study of the Earth’s climate addressing crucial questions of atmospheric and oceanic circulation, regional and global climate, and climate change.

The figure, below, shows Martian topography and albedo (reflectivity) on the native cube-sphere grid.  The full globe can be constructed by “folding” the edges of the domain together.  The major advantage over standard grid-point models is the absence of two “convergence” points at the poles.

Our paper on data assimilation (DA) for Mars has just been published and this week we’re also speaking about it at the American Geophysical Union meeting in San Francisco. DA is a method for ‘fusing’ an atmospheric / climate model with data. If the model works well, DA allows the global extrapolation of observations that have incomplete or irregular coverage. If the model works poorly, DA provides a very efficient means of figuring out what’s wrong with the model and a framework for testing improvements. DA is widely used for Earth science for everything from recent climate reconstruction to weather forecasting. It’s only very rarely been used for other planets, though, because of the difficulty of developing and maintaining the DA capability (the software) and the computational demands. The DART DA system for Mars changes all of this by augmenting an open-source NCAR-developed DA system for planetary use. As a teaser, here’s an incomprehensible but colourful figure from the paper

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The Mars Science Laboratory was injected into interplanetary cruise just a few moments ago (early morning PST, Nov 26).  Next stop will be Mars in August 2012.  This is the most complex landed vehicle ever sent to another planetary object. It possesses a range of sophisticated instrumentation, mostly focused on understanding the geology, geochemistry, and mineralogy of rocks in the Gale Crater landing site.  It has a few auxiliary instruments: a surface radiation detector, an active neutron subsurface sounder (which looks for subsurface ice or hydrated minerals), and a Rover Environmental Monitoring Station (REMS).  Ashima Research has been involved with the REMS instrument as a Co-I investigator since 2004. Looking forward to doing some meteorology on Mars!

Back in June we published a paper on our successful efforts to model the way solar and thermal radiation maintain Venus’ extreme climate (you can find the paper here). We also just got word that we’ll be presenting this work at the AGU conference in December, so we thought it time to give some insight into what we’re doing.  The goal of the project was two-fold: to create a self-consistent model that could stand up against spacecraft observations (i.e. to test how well “we” – the science community and our predictive models – really understand the greenhouse effect and solar heating of the atmosphere) and to develop a baseline for faster radiative transfer models that can be used in comprehensive climate models.  Why model Venus?  It’s an extreme case, it really stretches our understanding of atmospheric and climate physics and dynamics and it provides a very extreme test of our ability to model climate.  And you all know why we might care about how well we can model climate, right?

Image from the ESA Venus Express Venus Monitoring Camera.

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Ashima Research’s marsclimatecenter.com website just had a major update, with the addition of seven years of full colour, global images of Mars.  The data were collected between 1999 and 2006 by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC).  The images were created by Huiqun Wang, our colleague at Harvard.  The website allows you to select images by Earth date (day – month – year style) and Mars date (using areocentric solar longitude and Martian year).  You can also select from northern and southern polar images, and traditional global map-style images.  To read more about the images, check out the image data set description page.  To get going browsing, selecting, and/or downloading the images, check out the image archive search tool.