# Atmospheric Collapse

Under the right conditions, the atmosphere of a terrestrial planet can completely freeze and fall as snow/ice on the planet’s surface. This process is often called atmospheric'' collapse, a wonderfully omninous term for a pretty cool physical process. I am interested in how energy transport affects and is affected by atmospheric collapse. My work so far has focused on Mars, but Pluto, early Titan, and exoplanets are all locations where atmospheric collapse may be at work.

## Atmospheric Collapse on Mars

Due to the relatively high condensation temperature of carbon dioxide, the Martian atmosphere, which is 95% CO2, can almost completely condense (i.e., collapse) onto the planetary surface under the right conditions. Most of my PhD thesis work focused on understanding how the conditions for global atmospheric collapse of the Martian atmopshere are a function of CO2 inventory, planetary obliquity, solar luminosity, and atmospheric heat transport.

I investigated how the inclusion of non-parametric, time varying heat transport affects the onset of atmospheric collapse. I found that the range of obliquities and total CO2 inventories for which the Martian atmosphere collapses is larger than predicted. We used Reynolds decomposition to study the meridional eneragy transport in a collapsing atmosphere on Mars. The condensational flow due to CO2 condensation plays an important role in controlling the onset and maintenance of atmospheric collapse. I have published my first results on this work in Icarus.

I continue to investigate the dynamics of atmospheric collapse on Mars, with a particular interest in how collapse may have affected the evolution of the Martian climate.

##### Alejandro Soto
###### Senior Research Scientist

I am a planetary scientist and aerospace engineer.