Global warming on other planets (and moons) is one of the cute scientific observations that have amused many of us many times.
Mars for Martians
The topic got hotter in recent hours once again:
The observations erase the remaining doubts about the existence of the Martians. They also inform us about their skin color.
The Martians have to be old white male conservatives, otherwise their environment wouldn't be changing. Note that every change is bad.
But MRO isn't the only probe that is going to tell us something about the changes on Mars.
Mark Lemmon of Texas A&M – an atmospheric scientist – is participating in the mission involving the Curiosity rover whose aim is to "determine climate change and life on Mars": press release. Note that the spin is already incorporated to the definition of the problem, before they actually obtain any results.
The Curiosity rover, a part of the Mars Science Laboratory, is five times larger than the Spirit or the Opportunity rover. The weight of its mass instruments is higher by a factor of 10.
I want to say that lots of changes in the environment have been observed on Mars – not just the dunes on the move but also melting carbon dioxide polar caps and similar things.
And Mars seems like a more boring, static place than the Earth with its constantly varying cloud cover and turbulence in the atmosphere. The idea that the Earth should be naturally keeping its global mean temperature constant within tenths of a degree doesn't sound sensible given the facts we know, especially the big-picture physical facts that also involve those from other celestial bodies.
Some of the global warming on other planets (and our blue, not green planet) has been attributed to the Sun and/or nearby cosmic rays. The shared positive sign in most cases is suggestive but I remain an agnostic here. The internal, mostly random planetary variability is still a plausible explanation for all the changes.