It is right there in history. The time of the Roman empire was before industrialization. If we return to the climate of that era then we are returning to “normal” are we not?
When the dinosaurs roamed the Earth, for hundreds of millions of years, there was no ice at the poles.
The combination of the formation of the Himalayas (accelerated weathering to take CO2 out of the atmosphere) and separation of South America from Antarctica (so the polar currents formed, trapping cold air there, turning it into an ice box) both made the world cool significantly starting 40 million years ago.
Ice ages are an aberration over most of Earth’s 4.5 billion year history.
Boy, are you ever confused, so let me set you straight.
The reason Romans suffered from AGW -- manmade global warming -- is the same reason we have it now: Romans drove SUV chariots, diesel powered wagons, they burned coal & trees to heat up their baths, and besides their horses farted constantly pumping greenhouse gasses into the atmosphere.
That's why it was so warm, but thankfully barbarians from the north & east finally put an end to all that, and Europe went back into Dark & Little Ice Ages, when everybody (those still living) were much happier!
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