the oceans were warmer and the climate was warmer when giant reptiles roamed the earth and swam the seas . and the earth was cooler 12 thousand yrs ago when mammoths walked the earth and a land bridge allowed eastern Europeans to cross over to North America .. the climate changes ! and no ! there is nothing you can do about it ! deal with it !
While that is true it was warmer 100 million years ago, we would not like it because there was constant cloud cover, and no one would ever see the stars again.
There also are at least 12 recorded cycles of ice age cooling and warming, but that is a 110,000 year cycle that right now is just after the hottest period, so we are adding another artificial warming on top of the warmest of the normal cycle.
There is plenty we can do about it.
We know what causes the 110k year long cycles.
It gets hot, the plants do so well, they use up all the CO2, that prevent global heat retention, the climate gets cold until the plants all freeze and die.
When they decompose, the CO2 is returned, and it warms up again.
By burning old, sequestered, fossil fuels that are carbon based, or instead growing more carbon capturing plants, we can decide whether to increase or decrease global warming.
The carbon content of our atmosphere is totally up to us.
When we mine or drill old sequestered fossil fuel, we are releasing hundreds of millions of years worth of old plants, all at once.