And when that huge pile of trees finally started to burn, we got our first case of rapid global warming from burned carbon. The second one is done by humans right now.
Actually, burning of trees helped reduce CO2 over the long term. That's because burning is incomplete and produces charcoal. Charcoal doesn't decay, so when it is buried it semi-permanently takes carbon out of the biosphere. Over extended time, this would draw down atmospheric CO2. Some coal deposits from that period have a significant fraction of charcoal in them.
This doesn’t sound right. Iirc there have been many periods in earth’s history warmer than today, and carbon was part of the climate feedback for all of them, but this is the first time that warming is coming from direct forcing via co2.
Are you sure? Because my understanding is, in the past what has happened is that some other force causes a bit of warming, and then the oceans heat up, which causes co2 to bubble out, which then causes more warming, which causes more co2 to bubble out, and so on. So co2 is an active part of the picture but it wasn’t the independent variable, so to speak. Whereas now we’re mining fossil carbon and squirting it directly into the atmosphere, which is new.
And climate scientists are very smart and have worked out how much the added co2 amplified the original warming, and have been able to work out how much warming you would get by doubling co2 levels, which appears to be around 3 degrees C.
Hmm, I don’t think you read what I wrote very carefully. I’m making a very specific and rather technical point about the feedback loops in the climate.
Basically the amount of co2 that the ocean can have dissolved in it is a function of temperature and the relative co2 concentration of the air. When the temperature of the water increases it can hold less co2. Just like when soda gets warm and isn’t pressurized, it gets flat.