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The interesting observation is, the CO2 levels of the earth were flat for 2014. There was no net gain.
The earth naturally produces about 150 billion tons of CO2 per year. While human add about 5 billion tons of CO2 per year.
I am not sure where they get the 150 years CO2 dwell time, since that would mean 155 billion tons, times 150 year, builds up before any CO2 is reabsorbed? This is not observed. The dwell time for all the CO2 is closer to one year.
Quote from: puppypower on 09/01/2016 13:05:55The interesting observation is, the CO2 levels of the earth were flat for 2014. There was no net gain. Just plain wrong.http://co2now.org/Do you understand that making false claims like that mikes you look like you are a liar or an idiot?
Quote from: puppypowerThe earth naturally produces about 150 billion tons of CO2 per year. While human add about 5 billion tons of CO2 per year.It seems that there is a fair spread in estimates (estimates in different years will differ, since the emission rate is increasing year-on-year):Wikipedia suggests numbers like 210 gigatonnes exchanged with the atmosphere per year, but the atmosphere absorbs 6-10 gigatonnes more than it loses, every year. Skepticalscience suggests that the atmosphere exchanges about 200 Gt per year, gaining about 3 gigatonnes per year. But the key is that about 60% of human-produced CO2 remains in the atmosphere, without being absorbed. This leads to a steady increase in atmospheric CO2.QuoteI am not sure where they get the 150 years CO2 dwell time, since that would mean 155 billion tons, times 150 year, builds up before any CO2 is reabsorbed? This is not observed. The dwell time for all the CO2 is closer to one year. The CO2 concentration in the atmosphere does show a cyclic annual variation of about 1%, with dips attributed to the summer season in the northern hemisphere. Some of the carbon turned into leaf mass in spring gets turns back into CO22 in the fall and winter.If humans were not contributing extra CO2 by burning coal, and cutting down forests, you would expect that the summer dips would roughly equal the winter peaks.But we see that humans are unbalancing this, by burning fossil fuels, by producing cement, and by cutting down forests.As Mark suggests, something like 30-40% of emitted CO2 is absorbed in the ocean. But that does not mean it is "gone" - it acidifies the ocean waters, which will cause increasing problems for corals and shellfish. If and when the atmospheric CO2 drops, CO2 will be released from the oceans back into the atmosphere, where any remaining land plants will attempt to turn it into plant matter.So if a pulse of CO2 is injected into the atmosphere (as humans have been doing for a few hundred years, and as volcanoes do occasionally), it will take something like 100 years to return half way to the previous levels after the pulse ends.See the diagram & explanation at: http://www.skepticalscience.com/co2-residence-time.htm