Atmospheric CO2 increases

Many climatically sensitive feedback processes could be described in addition to those outlined above. We have restricted our attention to processes that have potentially large effects. A large effect is defined as one that could change the current rate of atmospheric CO2 increase by at least 50% ( 1 Pg C-yr"" ). 

Box models have a long tradition (Craig, 1957b Revelle and Suess, 1957 Bolin and Eriksson, 1959) and still receive a lot of attention. Most work is concerned with the atmospheric CO2 increase, with the main goal of predicting global CO2 levels during the next hundred years. This is accomplished with models that reproduce carbon fluxes between the atmosphere and other reservoirs on time... 

Atmospheric CO2 increase = Fossil Fuel Emissions Land Use -Emissions Ocean Uptake — Presumed terrestrial sink... 

Long-term measurements of atmospheric CO2 are available for a few clean-air locations on an almost continuous basis since 1978 (Keeling et al. 1979,1984,1989, 1995 Ciais et al. 1995 Mook et al. 1983). These measurements clearly demonstrate that on average atmospheric CO2 increases by about 1.5 ppm per year while the isotope ratio shifts toward lower ratios. The annual combustion of 10 g of... 

Figure 9.8. Atmospheric CO2 increase in the past 200 years as indicated by measurements on air trapped in old ice from Siple Station, Antarctica, and by the annual mean values from Mauna Loa Observatory. The line is a spline fit through all data. (After Siegenthaler and Oeschger, 1987.)...

The common masonry materials as limestones, marble, sandstones basalt and granite as well as artificial materials as brick, concrete and mortar are composed primarily of carbonate and silicate mineral. The natural weathering of these materials, due mainly to atmospheric CO2, increases at an alarming rate due to atmospheric acidity and acid precipitation. 

Blunier T., Schwander J., Stauffer B., Stocker T., Dallenbach A., Indermuhle A., Tschumi J., Chappellaz J., Raynaud D., and Barnola J.-M. (1997) Timing of Antarctic Cold Reversal and the atmospheric CO2 increase with respect to the Younger Dryas event. Geophys. Res. Lett. 24, 2683-2686. 

The atmospheric burden of anthropogenic CO2 is very well known because it has been measured since 1958 and recent ice core studies indicate how the atmospheric CO2 evolved between the pre-industrial period and 1958 (Fig. 11.3). Because industries and governments keep records of the amount of fossil fuel recovered, this number is also known. The amount of atmospheric CO2 increase over the period 1860-1989 is estimated to be only 40% of total emissions (Table 11.1). Where has the rest gone ... 

Permanent growth - as stated by politicians - will not solve life problems such as employment this is a question of reorganizing society. After productivity (expressed as constant annual turnover) satisfies social consumption needs, stationary conditions are then achievable, i. e. A becomes zero in Eq. (2.143). Naturally, the human population will (and must) tend to a constant number. This limitation process is likely to go on over the next 200 years. Another limitation must be set through per capita consumption to provide social and cultural standards. The growth, however, is going on this century. Without revolutionary technological changes, the climate becomes out of control. As stated above, the atmospheric CO2 increase must be stopped within the next few decades. There are several ways ... 

Variations in atmospheric oxygen have provided unique insight into carbon sources and sinks. Between 1990 and 1997, the mixing ratio of atmospheric O2 decreased by 25 ppmv, when that of atmospheric CO2 increased by 9 ppmv. The decrease in O2 is less than expected from fossil fuel combustion, which has an 02 C02 ratio of 1.43 0.02. As air-sea exchange of CO2 has little impact on atmospheric oxygen, and net land uptake has a O2 CO2... 

FIGURE 7 Interannual variations in the fossil fuel emission and atmospheric increase in CO2. The difference between the two is the carbon sink. The varying rate of CO2 increase in the atmosphere reflects the response of the terrestrial biosphere and ocean to interannual climate variations. After 1988, global sink strength increased, while the atmosphere CO2 increase slowed down. 

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