Carbon dioxide and global temperature: The direction of causation

Carbon dioxide is a greenhouse gas. The increase of carbon dioxide increases the earth’s temperature. The increase of global temperature, by reducing the solubility of carbon dioxide in ocean water, increases the concentration of carbon dioxide in the atmosphere. In the graphs of carbon dioxide concentration and global temperature, they often move together. Which one is the primary driver? Or they reinforce each other with similar force?

Starting about 18,000 years ago, carbon dioxide and global temperature started to rise together. Around 12,000 years ago, they both plateaued and fluctuated somewhat since. From 18,000 to 12,000 years ago, the rise of carbon dioxide is from about 180 to 260 ppm. The temperature change is about 8 degrees. In the last two hundred years, the rise of carbon dioxide is from about 280 to 410 ppm. During the same period of time, the rise of global temperature is about 2 degrees. Hence, the primary driver between temperature and carbon dioxide is temperature. The rise of temperature drives the rise of carbon dioxide. The rise of carbon dioxide has relatively minor role in the rise of temperature. This is not surprising, since 95% of greenhouse effect is caused by water vapor.

More data and explanation can be found from the following websites.

https://geocraft.com/WVFossils/global_warming.html

https://geocraft.com/WVFossils/ice_ages.html#anchor2117056

https://geocraft.com/WVFossils/last_200_yrs.html

https://geocraft.com/WVFossils/last_50k_yrs.html