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Current atmospheric CO_2 concentrations are the highest on record in the last half a millionyears and are expected to reach between 540 and 970 ppm over the next one hundred years. Thisunprecedented increase is linked to human activities including fossil fuel combustion anddeforestation. The increase in CO_2 concentrations, and to a lesser extent in other greenhouse gases,is linked to changes in climate patterns and variability, and to an average global warming of 0.6℃during the 20th Century (IPCC 2001). Changes in land use and cover are critical controls of the distribution and strength of carbon
Current atmospheric CO_2 concentrations are the highest on record in the last half a million years and are expected to reach between 540 and 970 ppm over the next one hundred years. Thisunprecedented increase is linked to human activities including fossil fuel combustion and before. , and to a lesser extent in other greenhouse gases, is linked to changes in climate patterns and variability, and to an average global warming of 0.6 ° C during the 20th Century (IPCC 2001). Changes in land use and cover are critical controls of the distribution and strength of carbon