Real question is: What ended the last ice age?
All we can say for sure is that ocean currents changed and it was not due to a build up of global warming gases. Therefore there is far more complexity in climate change than just greenhouse gases. Simple answers seldom work for complex problems. In spite of extreme political pressure, scientists are still asking questions. It’s as if they didn’t know the “science is settled”.
Real question is: What ended the last ice age?
Orbital mechanics and long term solar cycles, and it did not have a damn thing to do with CO2 levels. CO2 was at a low level during the ice age as the ocean is where most CO2 lives. When the ocean is cold it can hold more CO2. When the ocean is warmer it can hold less CO2. This is very basic chemistry. Take two bottles of Coke, and put one in the refrigerator and the other your car on a sunny day. Open them both and the hot one will bubble and spill out bubbles of CO2 and the cold one will mildly fizz. It is that simple. CO2 levels are a function of the warmth of the ocean.
We swapped orbits with Mars, again.