Read here. Back in 2009, NASA launched a new satellite that was supposed to locate the 'missing CO2' that the IPCC has found so elusive, to the point of embarrassment. Being unable to account for the still AWOL CO2, which of course is the main ingredient in the IPCC's AGW hypothesis, is well...er...an embarrassment. Unfortunately, the satellite launch failed. A failure likely due to Obama's NASA of HOPE, since they now think there is a higher calling than actual science and launch successes, which is a whole nother story.
With that snark accomplished, the major problem of the missing CO2 remains and there is now a new study (more on that later) that proffers a new hypothesis to the missing CO2 riddle.
Currently, what is absolutely known about the missing CO2 is that it implies the IPCC's AGW "settled" climate science is not really settled, by a long shot. Essentially here are the facts regarding the "missing CO2."
1. Scientists estimate that only 50% of each years new CO2 emissions can be accounted for - yes, that means the other 50% is missing.
2. Since pre-industrial times, some 499 billion tons of CO2 has been emitted by humans.
3. Since pre-industrial times some 266 billion tons have been stored in the atmosphere; some 118 billion tons has been stored in the oceans; and, these two figures combined represent 334 billion tons stored.
4. Since pre-industrial times, some 165 billion tons of human CO2 emissions have gone missing. (The 165 figure is the difference between 499 and 334 billion tons.)
5. The IPCC "scientists" claim that emitted human CO2 emissions remain in the atmosphere from hundreds to thousands of years.
6. The vast majority (see above chart) of peer-reviewed studies have determined that CO2 only remains in the atmosphere some 5 to 15 years. (click on chart to enlarge)
Based on all the above, how could any climate scientist, let a lone the IPCC, claim that the science is "settled"? Not only are vast amounts of CO2 emissions not accounted for on a yearly basis, there is also the known IPCC claim that human CO2 emissions are stored in the atmosphere for hundreds to thousand of years yet 50% goes "missing" each year - in other words, in reality, it ain't stored in the atmosphere.
Thus, not surprisingly, the IPCC and its quack climate scientists resort to a lot of hand-waving and mumbo-jumbo speculation to get around these known, major embarrassing CO2 issues with the AGW hypothesis.
Now comes a new study based on...ahem...a computer model that suggests the missing CO2 actually is being absorbed by the terrestrial biosphere. Esser et al. propose that a requisite combination of CO2 and nitrogen aerial fertilization explains how the "missing CO2" has actually been absorbed by vegetation, which means it's definitely not remaining in the atmosphere for hundreds or thousands of years.
As one can see, the science is far from settled and there is no current consensus as to where the 'missing CO2' goes - that's why scientists like Esser et al. keep performing new research.
"In pursuing this course of action, Esser et al. found that nitrogen fertilization of the biosphere in the absence of an increase in the air's CO2 concentration "would result in only minor additional carbon accumulation in plant biomass," while rising CO2 alone, without consideration of the nitrogen cycle, would bind roughly half of the carbon in the postulated carbon sink. And in the most realistic situation of all, they determined that "a complete ensemble of rising atmospheric CO2 and N2 fixation, denitrification, and leaching is necessary to achieve the 160 Pg [billion tons] C bound in the terrestrial biosphere between 1860 and 2002 as required by the missing sink concept." [GERD ESSER, JENS KATTGE, ABDULLA SAKALLI1 2011: Global Change Biology ]