IPCC Carbon Cycle AR5


The caption from page 471 of the IPCC Report AR5.


Figure 6.1 | Simplified schematic of the global carbon cycle.


Numbers represent reservoir mass, also called ‘carbon stocks’ in PgC (1 PgC = 10^15 gC) and annual carbon exchange fluxes (in PgC yr–1).


Black numbers and arrows indicate reservoir mass and exchange fluxes estimated for the time prior to the Industrial Era, about 1750 (see Section for references).


Fossil fuel reserves are from GEA (2006) and are consistent with numbers used by IPCC WGIII for future scenarios.


The sediment storage is a sum of 150 PgC of the organic carbon in the mixed layer (Emerson and Hedges, 1988) and 1600 PgC of the deep-sea CaCO3 sediments available to neutralize fossil fuel CO2 (Archer et al., 1998).


Red arrows and numbers indicate annual ‘anthropogenic’ fluxes averaged over the 2000–2009-time period.


These fluxes are a perturbation of the carbon cycle during Industrial Era post 1750.

These fluxes (red arrows) are: Fossil fuel and cement emissions of CO2 (Section 6.3.1), Net land use change (Section 6.3.2), and the Average atmospheric increase of CO2 in the atmosphere, also called ‘CO2 growth rate’ (Section 6.3).


The uptake of anthropogenic CO2 by the ocean and by terrestrial ecosystems, often called ‘carbon sinks’ are the red arrows part of Net land flux and Net ocean flux.


Red numbers in the reservoirs denote cumulative changes of anthropogenic carbon over the Industrial Period 1750–2011 (column 2 in Table 6.1).


By convention, a positive cumulative change means that a reservoir has gained carbon since 1750. The cumulative change of anthropogenic carbon in the terrestrial reservoir is the sum of carbon cumulatively lost through land use change and carbon accumulated since 1750 in other ecosystems (Table 6.1).


Note that the mass balance of the two ocean carbon stocks Surface ocean and Intermediate and deep ocean includes a yearly accumulation of anthropogenic carbon (not shown).  Uncertainties are reported as 90% confidence intervals.


Emission estimates and land and ocean sinks (in red) are from Table 6.1 in Section 6.3. The change of gross terrestrial fluxes (red arrows of Gross photosynthesis and Total respiration and fires) has been estimated from CMIP5 model results (Section 6.4).


The change in air–sea exchange fluxes (red arrows of ocean atmosphere gas exchange) have been estimated from the difference in atmospheric partial pressure of CO2 since 1750 (Sarmiento and Gruber, 2006).


Individual gross fluxes and their changes since the beginning of the Industrial Era have typical uncertainties of more than 20%, while their differences (Net land flux and Net ocean flux in the figure) are determined from independent measurements with a much higher accuracy (see Section 6.3).


Therefore, to achieve an overall balance, the values of the more uncertain gross fluxes have been adjusted so that their difference matches the Net land flux and Net ocean flux estimates.  Fluxes from volcanic eruptions, rock weathering (silicates and carbonates weathering reactions resulting into a small uptake of atmospheric CO2), export of carbon from soils to rivers, burial of carbon in freshwater lakes and reservoirs and transport of carbon by rivers to the ocean are all assumed to be pre-industrial fluxes, that is, unchanged during 1750–2011.  Some recent studies (Section 6.3) indicate that this assumption is likely not verified, but global estimates of the Industrial Era perturbation of all these fluxes was not available from peer-reviewed literature.  


The atmospheric inventories have been calculated using a conversion factor of 2.12 PgC per ppm (Prather et al., 2012).


Section for a video or follow-on comment

We should revisit occasionally what the proper role of government is.   As the constitution was a good sense of direction, we need a core set of principles to add in order to deal with the future.


So many want to engineer society, remove risk, assist certain groups, rather than let individuals thrive and raise communities.  Why?


Is Democracy where we all "get it good and hard" or is it the best means to a free society?


Should we roll with the special interests, or make the government achieve its proper role, what is that role, and how to do this?


When do deficits and governments become too large?


Government is becoming more elitist while trying to sell corrections to problems it created, what makes this possible?


Could include a pic

This could also be inserted into the field above, or erased


Currently as a society, we are having a most difficult time discussing political issues.  What is driving this?   And why a rebirth in political culture would be a good thing.


Market Economy

Are "markets" dead as some would conjecture? Or is free enterprise what got us here?


Economic Theories

At the heart of economics there are several possible economic schools of thought, the essence of these schools of thought and how they relate to our lives.


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