I think there are a lot of errors in the models. Tree rings can only go back so far because most of the early trees are now coal. And trees, while they do live for a long time, don’t live forever. Fossilization is rare and I don’t know if we can get weather data from fossilized tree rings. Carbon dating is useful for organic matter up to 60,000 years ago. The other methods used to determine what the atmosphere was in the past include studying ice samples from Antarctica but that’s only good for the time Antarctica froze till now, it was tropical at some point. Since most scientist think complex life has been around for 500 million years I don’t think we can really say we know exactly what the climate was like and how it changed anywhere past a certain time period.
I think there are a lot of errors in the models. Tree rings can only go back so far because most of the early trees are now coal. And trees, while they do live for a long time, don’t live forever. Fossilization is rare and I don’t know if we can get weather data from fossilized tree rings. Carbon dating is useful for organic matter up to 60,000 years ago. The other methods used to determine what the atmosphere was in the past include studying ice samples from Antarctica but that’s only good for the time Antarctica froze till now, it was tropical at some point. Since most scientist think complex life has been around for 500 million years I don’t think we can really say we know exactly what the climate was like and how it changed anywhere past a certain time period.