The sun was dimmer in the past, so similar co2 levels as then mean more warning. https://www.skepticalscience.com/co2-higher-in-past.htm https://www.skepticals

The sun was dimmer in the past, so similar co2 levels as then mean more warning. https://www.skepticalscience.com/co2-higher-in-past.htm https://www.skepticalscience.com/co2-higher-in-past.htm