Not wise
It's well known and undisputed that the last few million years in comparison to the recent hundreds of millions [or the starting point of multicellular life] that it has generally been much cooler.
I would be VERY interested in any serious attempt which disputes this. The reason it is undisputed is because there has a lot of scientific work in this area [and people like Al Gore have very little interest in this science].
On Earth there is no such thing as 5 million year old ice- which has been discovered so far. Whereas on Mars it might possible [and probable] to have ice 5 million years old or much older.
Of course ice isn't the only record, mud is also good.