The reason that global CO2 levels rise and fall in response to the global temperature is because cold water is capable of retaining more CO2 than warm water. That is why carbonated beverages loose their carbonation, or CO2, when stored in a warm environment. We store our carbonated soft drinks, wine, and beer in a cool place to prevent them from loosing their ‘fizz’, which is a feature of their carbonation, or CO2 content. The earth is currently warming as a result of the natural Ice Age cycle, and as the oceans get warmer, they release increasing amounts of CO2 into the atmosphere.
Because the release of CO2 by the warming oceans lags behind the changes in the earth’s temperature, we should expect to see global CO2 levels continue to rise for another eight hundred years after the end of the earth’s current Interglacial warm period. We should already be eight hundred years into the coming Ice Age before global CO2 levels begin to drop in response to the increased chilling of the world’s oceans.