Stratocumulus clouds become unstable and break up when CO2 rises above 1,200 ppm. The collapse of cloud cover increases surface warming by 8 C globally. This change persists until CO2 levels drop below 500 ppm.

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Stratocumulus clouds become unstable and break up when CO2 rises above 1,200 ppm. The collapse of cloud cover increases surface warming by 8 C globally. This change persists until CO2 levels drop below 500 ppm.