Question

what is the difference between climate of the past and present

Answer 1

All the “pasts” are not of equal interest for us :

first of all the phenomenum we are presently considering is happening on a very short time scale compared to the billions of years our planet has already lived : a century represents only 0,0000025% of earth’s age ! It is of course possible to get some hints on what were the average climatic conditions on earth a very long time ago (say a couple millions years, or a couple of hundred million years), but it will not be possible to know precisely how things evolved over a century then. For example, it is not possible to know how the average climatic conditions evolved between 60.000.000 years before present and 60.000.100 before present (or between 60.000.000 years before present and 59.999.900 years before present).

,As we are basically interested in the survival and the comfort of our own species (the survival of the rest of the biosphere is meaningful only if we are still here : on a planet where humankind would have disappeared, knowing wether there would still be tigers seems a secondary question to me !), what happened before humankind existed (regarding the climate) is less interesting than what happened after.

Answer 2

The past climate is is 2 degrees cooler than present climate this is causing global warming