Carbon emissions atmospheric concentration

Key I. Billion persons 2. cities with population greater than 8 million 3. average daily food production in caloriescapita 4. annual fish catch in million tons 5. annual water use in cubic kilometers 6. index of forest cover, 1950 = 100 7. annual CO2 emissions in billion tons of carbon 8. atmospheric concentration of CFCs in parts/billion. 

The rollback approach assumes that emissions and atmospheric concentrations are linearly related, i.e., that a given percentage reduction in emission will result in a similar percentage reduction in atmospheric concentrations. This is most likely a valid assumption for a nonreactive gas such as carbon monoxide, whose principal source is the automobile. The model is... 

Future emissions and concentration of carbon dioxide Key ocean/atmosphere/land analyses. Tech. Pap. 31, Div. of Atmos. Res., Comm. Sci. and Ind. Res. Org., Melbourne, Victoria, Australia. 

As was stated in Chapter 9, fossil fuels will remain the mainstay of energy production well into the twenty-first century. The availability of these fuels to provide clean, affordable energy is essential for the prosperity and economic endeavor. However, increased concentrations of COz due to carbon emissions are expected unless energy systems reduce the carbon emissions to the atmosphere. 

Trends in atmospheric concentrations and anthropogenic emissions of carbon dioxide. (From Oak Ridge National Laboratory, Carbon Dioxide Information Analysis Center, http //cdiac. 

It is debatable what the emission rate is that would stabilize the atmospheric C02 concentration at an acceptable level. Similarly, it is not known how much the emission charge should be to reach that target rate. According to an MIT study released in March 2007, if a global carbon emission charge of 25/ton was applied, this would result in stabilizing the global C02 emission at today s rate of 28 billion tons per year by 2050. 

Section 7.2.2. The reservoir of carbon in fossil fuels and mudrocks is also substantial and a major portion of the latter is thought to be recoverable and thus available for burning. The smallest reservoirs are the land biosphere (2000 GtC) and the atmosphere (749 GtC, equivalent to an atmospheric concentration of about 3 54 ppm). It is the small size of the latter which makes it sensitive to even small percentage changes in the other larger reservoirs, where these changes result in emissions to the atmosphere, as, for example, in the burning of fossil fuels. 

The atmospheric concentration of CO2 rose from 280 ppm in 1800 to 370 ppm in 2000, mainly due to the consumption of fossil fuels. This increase in CO2 concentration is expected to have various environmental and ecological effects. For example, doubling of the CO2 concentration in the atmosphere reduces the rate of calcium carbonate deposition in coral reefs by 30-40%.Most of this rise has occurred over the last few decades, and, unless action is taken, the projected growth over the 21st century could lead to a doubling or tripling of the preindustrial level of C02. Unlike for SO2 emission, the total accumulation of CO2 matters rather than the rate of CO2 emission. Oceanic uptake of CO2 can compensate for some emissions, but this uptake will collapse once CO2... 

Carbon monoxide (CO) is also formed in aquatic environments from the photochemical degradation of DOM [3,4,8,22,94-105]. Strong gradients of CO have been observed in the lowest 10 metres of the atmosphere over the Atlantic Ocean [97]. The samples nearest the ocean surface were some 50 ppb higher than at the 10-metre altitude-sampling inlet. This implies that the ocean is a source of CO to the atmosphere and that this source can increase the atmospheric concentration. CO is reactive in the troposphere and thus its emissions from the ocean may influence the hydroxyl radical (OH) and ozone concentrations in the marine atmospheric boundary layer that is remote from strong continental influences. 

The 11-15 year Kyoto targets are clearly inadequate to make any dent in future atmospheric concentrations, which is the crucial measure of danger to climate. Even if the protocol were fully implemented, it would only serve to delay by less than a decade the date in the next century at which global carbon dioxide concentrations, under current emissions trends projected by IPCC, would cross the 550 parts per million (ppm) mark that represents a doubling of preindustrial concentrations... 

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