Carbon Cycles and Sinks

Carbon Cycles[1]

According to Wikipedia[1] "the carbon cycle is the biogeochemical cycle by which carbon is exchanged between the biosphere, geosphere, hydrosphere, and atmosphere of the Earth (other astronomical objects may have similar carbon cycles, but nothing is yet known about them).

The cycle is usually thought of as four major reservoirs of carbon interconnected by pathways of exchange. The reservoirs are the atmosphere, the terrestrial biosphere (which usually includes freshwater systems and non-living organic material, such as soil carbon), the oceans (which includes dissolved inorganic carbon and living and non-living marine biota), and the sediments (which includes fossil fuels). The annual movements of carbon, the carbon exchanges between reservoirs, occur because of various chemical, physical, geological, and biological processes. The ocean contains the largest active pool of carbon near the surface of the Earth, but the deep ocean part of this pool does not rapidly exchange with the atmosphere.

The global carbon budget is the balance of the exchanges (incomes and losses) of carbon between the carbon reservoirs or between one specific loop (e.g., atmosphere - biosphere) of the carbon cycle. An examination of the carbon budget of a pool or reservoir can provide information about whether the pool or reservoir is functioning as a source or sink for carbon dioxide."

The Global Carbon Cycle[2]

TecEco, a client company, plan through Gaia Engineering to modify the carbon cycle by creating a new sink in the built environment. The need for a new and very large sink can be appreciated by considering the balance sheet of global carbon in the crust depicted below

Global Carbon Sinks[3]

Carbon Sinks and Anthropogenic Actual and Predicted Consumption of Carbon[4]

According to Ziock, H. J. and D. P. Harrison "The size of natural carbon sinks or pools compared to fossil fuels reserves and to potential emissions in the new century. For emissions we show four blocks of 600 Gt each. 600 Gt would be the result of 100 years of constant emissions at the current rate. If the last century is any guide, the output could be five to six times larger. In the emission column below the zero line we show the far smaller total emissions of the 20th century, which in turn dwarfed the emissions of the 19th century. Individual blocks below the zero line represent 100 years of emission at the rate of 1900. The easily accessible carbon reservoirs with the exception of the ocean are comparable in size to the expected emissions of the next century. However, one would be hard pressed to actually double the existing biomass without substantively changing the environment. The ocean reservoir, at 39,000 Gt of carbon, is far larger, but its ability to take up carbon without environmental change is limited. Above the zero line, we are showing the amount of carbon that when dissolved in the ocean in the form of CO2 would change its pH from top to bottom by 0.3. .....The resource columns show that available fossil energy exceeds all likely demand for at least a century or two."

Why we Need Carbon Sinks

Assuming Kyoto commitments are met (which is unlikely) it is estimated that global emissions will be 41% higher in 2010 than in 1990.[5] We are making insufficient progress towards reducing emissions because we are too hooked on energy. We must also rapidly implement carbon sinks if we are to have any hope of arrresting runaway global CO2 increases.

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