Among other objectives, NASA's 1958 mission statement includes conducting aeronautical and space activities of the US for "the expansion of human knowledge of phenomena in the atmosphere and space".

So: atmospheric climate science directly falls under NASA's responsibilities.

https://en.wikipedia.org/wiki/National_Aeronautics_and_Space...

NASA launches and operates Earth-observing satellites for measuring the weather and climate.

Living on Mars long-term is a practical impossibility. Certainly much, much harder than living on even a climate-changed Earth.