Your out of date dude. We're coming up on 397 now.<quoted text>
You should have stopped at "I'm not sure"
It would have been the smartest thing you have said thus far.
Earth's atmosphere today contains about 380 ppm CO2 (0.038%). Compared to former geologic times, our present atmosphere, like the Late Carboniferous atmosphere, is CO2- impoverished! In the last 600 million years of Earth's history only the Carboniferous Period and our present age, the Quaternary Period, have witnessed CO2 levels less than 400 ppm.
CO2, warmth, ocean levels have been different in the past, but so was the Earth. Comparing our earth with the one 60 mya, or 200 mya, or 600 mya, is like comparing apples and orangutans.