It's not that I doubt you're assertion, but proof is required for those doubting Thomas's amongst us.
There are many other references if you look.
Actually a quick Google or even search of FR will show valid studies on warming of several planets, not just Mars.
The sun is in a warming cycle. We have no idea why and we still are mostly in the dark when it comes to the sun and its longer cycles, much less the shorter ones. Think harmonics and how different frequencies will dampen or increase the amplitude of the frequency. Same with the sun and its cycles.
Even more interesting is that every ice age was preceded by warming and an increase in CO2. At the time the temp dropped, so did CO2 concentrations. There is a self regulating mechanism in the earth's makeup, probably ocean currents.