[palmer]

There has been a 1 or 2 C rise in ocean temperatures over the last century, mostly as the result of coming out of the Little Ice Age. That would cause a 5 to 10 ppm rise in CO2. Instead we have seen a 110 ppm rise in CO2. There is clearly an effect from rising ocean temperatures but there is a bigger effect from manmade emissions.

The oceans no longer emit CO2 as they warm, they now absorb some of our extra CO2 although they absorb less of our extra than they would if they were not warming.

[aruanan]

There has been a 1 or 2 C rise in ocean temperatures over the last century, mostly as the result of coming out of the Little Ice Age. That would cause a 5 to 10 ppm rise in CO2. Instead we have seen a 110 ppm rise in CO2. There is clearly an effect from rising ocean temperatures but there is a bigger effect from manmade emissions.

There has been a 0.7C rise in atmospheric temperatures since about 1850, though we're still considerably below the high of the Medieval warm period. We haven't had a rise of 110 ppm. The 280 ppm for the 19th century was cherry-picked. The average was somewhere between 300-340 ppm. We've gone up slightly since then and the increasing CO2 is coincident with stable (since 1998) and falling (since 2009 or so) atmospheric temperatures. Since 2009, there has been a global decrease of about 0.6C, almost as much as was gained through the three warming periods after 1880. The rise in atmospheric CO2 started before the beginning of the Industrial Revolution. Human contribution is a minor portion of the total increase. Its effects on temperature cannot be distinguished from background noise. Compared to annual fluctuations due to seasonal change, they are minuscule. Most of the effects of CO2 on atmospheric temperature is over the first 100 ppm. The larger the amount, the increasingly smaller the effect by unit. We'd all be better off with 600-800 ppm.