[indy]

"To throw around some numbers: about 220 petagrams (gigatonnes) of carbon dioxide will be released into the atmosphere this year; around 3% from burning fossil fuels; 44% from the ocean surface; and 53% from the land"

Does the 3% from burning fossil fuels seem too low? I thought that this would make up the majority of carbon dioxide released into the atmosphere every year

[Sharlin]

You’re confusing net and gross carbon release. In a balanced system, on average 100% of released carbon will be reabsorbed, by rocks, oceans, and (to a fairly small extent) plants, making the net rate of change of atmospheric carbon practically zero. Then humans began to meddle with things, starting to introduce extra carbon to the atmosphere from outside the primary carbon cycles. Carbon fixing rate has also increased to compensate (leading to further problems like acidification of the oceans) but has not been able to keep up, especially because the excess anthropogenic release rate has been growing exponentially. Thus the net release rate has been slightly above zero for the past 200+ years, and it’s starting to show.

[kiicia]

This is extra carbon that is excess to natural carbon cycle and it cumulates year to year. Now after 100+ years of carbon excess we are here…

[jrimbault]

Nope it's right. Consider that our atmosphere is a balancing act which we're just tipping.