Is man-made CO2 different: 1000 years? Try 4 years.
That CO2 you emitted last Tuesday, is it coming back next month, next year or in March 3011?
Tim Flannery makes it clear that CO2 circulates o-so-slowly, circa “a thousand years”. Remember that CO2′s “greenhouse” effect occurs at speed-of-light timescales, so if the temperature is still affected, so must be the CO2 (according, at least, to the world-of-Flannery).
If we cut emissions today, global temperatures are not likely to drop for about a thousand years… Just let me finish and say this. If the world as a whole cut all emissions tomorrow the average temperature of the planet is not going to drop in several hundred years, perhaps as much as a thousand years because the system is overburdened with CO2 that has to be absorbed and that only happens slowly. [Thanks to Andrew Bolt]
There are a few clues that maybe CO2 doesn’t idle the centuries away aloft, and that (I know you’ll be shocked) the Climate Commission (and IPCC) have overstated things: if emissions are absorbed by the global system in a matter of months, it rather blows the idea that we have to act decades ahead to stop the catastrophe. If CO2 levels adjust quickly, our “sins” will be much more quickly forgiven, and we can wait-and-see.
The thousand year timeframe doesn’t fit very well with NASA’s official carbon cycle, and the empirical evidence.
You can see below in the NASA diagram that plants absorb 16% of all the carbon dioxide in the entire atmosphere each and every year (121Gt of the 750 Gt in the air) and oceans absorb 12%, meaning that 28% of all the CO2 in the global atmosphere is sucked down each year. Let’s call it “one quarter”.
In any given year, tens of billions of tons of carbon move between the atmosphere, hydrosphere, and geosphere. Human activities add about 5.5 billion tons per year of carbon dioxide to the atmosphere. The illustration above shows total amounts of stored carbon in black, and annual carbon fluxes in purple. (Illustration courtesy NASA Earth Science Enterprise)
If a quarter of all atmospheric CO2 is being turned over each year, that implies that if humans found the fountain-of -endless-energy, and stopped emitting any CO2 tomorrow, that within just four years, only about 30% of that co2 would remain. Indeed 90% of all the emissions that we’d ever put up there, since King Tut built a pointy-rock-house, would be gone by… 2020. (Jo Nova)