Oceans CO2 uptake

Gross Annual Ocean CO2 Uptake Net Ocean CO2 Uptake0 River Export of Carbon to Oceans... 

Matear R. J. and Hirst A. C. (1999) Climate change feedback on the future oceanic CO2 uptake. Tellus 51B, 722-733. 

The uptake flux for the Northern Hemisphere ocean (north of 14°N) is 1.2 Pg-C y, whereas that for the Southern Hemisphere ocean (south of 14°S) is 1.7Pg-Cy . Thus, the Southern Hemisphere ocean is astronger CO2 sink by about 0.5 Pg-C y . This is due partially to the much greater oceanic areas in the Southern Hemisphere. In addition, the Southern Ocean south of 50°S is an efficient CO2 sink, for it takes up about 26% of the global ocean CO2 uptake, while it has only 10% of the global ocean area. Cold temperature and moderate photosynthesis are both... 

Another model, first introduced by Moore, et al. (2i), was used to examine the role of terrestrial vegetation and the global carbon cycle, but did not include an ocean component. This model depended on estimates of carbon pool size and rates of CO2 uptake and release. This model has been used to project the effect of forest clearing and land-use change on the global carbon cycle (22, 23, 24). 

The initial decrease in ocean uptake rate will eventually be reversed once enough time has passed (millennia) for meridional overturning circulation to recycle the subsurface waters. This will serve to inject CO2 below the mixed layer. Once the surface waters have been sufficiently acidified and are transported into the deep sea, they will eventually start dissolving sedimentary calcium carbonate. The resupply of alkalinity via this route will provide sufficient enhancement to ocean carbon uptake capacity to... 

Nuclear weapons testing in the atmosphere introduced excess l4C that has proven to be an excellent tracer for processes that will be important in the uptake of fossil fuel CO2. For example, Peng (1986) mapped global uptake patterns of excess 14C and used these to calculate fossil fuel CO2 uptake by the oceans. His results indicate that about 10% of the fossil fuel CO2 is "missing". In the next chapter we will discuss the possibility that this missing CO2 may be the result of dissolution of highly soluble magnesian calcites from shallow water sediments. Also, Feely and... 

Inclusion of coastal ocean estimates of CO2 uptake for high-latitude regions into global ocean estimate increases the total uptake by 57% (—1.93 compared to -1.56 Pg C y-1). 

Robertson J. E. and Watson A. J. (1992) Thermal skin effect of the surface ocean and its implications for CO2 uptake. Nature 358, 738-740. 

In their hypothesis of a glacial decrease in Southern Ocean CO2 leak, early workers considered two causes (i) an increase in biological export production and (ii) a decrease in the exposure rate of deep waters at the polar surface (Figure 7). One can imagine processes that would have reduced the evasion of CO2 from the Southern Ocean by either of the two mechanisms mentioned above. For instance, an increase in the input of dust and its associated trace metals to the Southern Ocean might have driven an increase in the rate of nutrient and carbon uptake by phytoplankton (Martin, 1990). Alternatively, an increase in the salinity-driven stratification of the Antarctic and/or a decrease in wind-driven upwelling could have lowered the rate of nutrient and carbon dioxide supply to the surface... 

Rate of Removal of CO2 from Atmosphere Depends on Ocean Circulation Ocean circulation has a major impact on the distribution of carbon between the ocean and the atmosphere. Figure 15.20 is an extension of the two-box model used in Figure 15.16. The CO2 uptake is very rapid at first but... 

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