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What isare the temperature and pressure inside the CO$_2$ deposit on Mars?

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What is the temperature and pressure inside the CO$_2$ deposit on Mars?

Within the CO$_2$ deposit near the south pole on Mars, according to this article 3 subunits have been found with one having a top CO$_2$ layer of about 300 meters thick covered by a water ice layer with a thickness of up to 20 meters (Figure 4).

Is it known what the temperature and pressure are within the subunits or could they be calculated or estimated ?