Fossil fuel combustion global climate change

In spite of the occurrence of natural events such as the eruption of Krakatoa, scientists are now well aware that human activities can have serious long-term effects on the Earth s atmosphere. The hrst such effect to be noticed historically was the increase in acid precipitation resulting from the combustion of fossil fuels. Acid precipitation is also known as acid rain or acid deposition. The second, discovered in the mid-20th century, was the depletion of stratospheric ozone. More recently, atmospheric scientists established a link between so-called greenhouse gases and global climate change. 

The consumption of fossil fuels is not sustainable. With business as usual, the proven and economically recoverable fossil reserves will be exhausted in little more than 100 years. Substitution of fossil fuels is therefore required anyway on the long term. If CO2 emission from fossil fuel combustion is responsible for adverse climate changes like global wanning, substitution is desirable on the short term. The share of the renewable energy sources like wind, hydropower and biomass may be increased in a relatively short time. Each of these traditionally well known sources can contribute a... 

Humanity s major sources of energy are derived from fossil fuels, principally oil, gas, coal, and wood. The major combustion by-products of fossil fuel burning include sulfur dioxide (SO2), carbon dioxide (CO2), and nitric oxide (NO2), and partially oxidized hydrocarbons. The process of burning fossil fuels in thermal power plants, factories, homes, and motor vehicles emits enormous amounts of the aforementioned pollutants. The most important environmental concerns resulting from fossil fuel use are global climate change, acid rain, surface ozone, and partic-ulate-Zaerosol-bound toxins. 

Fig. 7.6 Global annual emissions of C02 from fossil-fuel combustion and cement manufacture. After IPCC (1990). With permission of the Intergovernmental Panel on Climate Change.

Between 1850 and 1998 atmospheric carbon dioxide levels have risen from 285 to 366 ppm, mainly because of the combustion of fossil fuels and changes in land use from forestry to agriculture. This unbalanced release of stored carbon is now generally accepted as setting us on a global climate change journey with an unknown but likely to be unpleasant destination. Combustion of fossil fuels alone contributed 6.3 Gt (gigatonnes or 10 tonnes) of carbon dioxide emissions annually between 1989 and 1998. 

In his cover letter to President Clinton, John Gibbons, director of the White House Office of Science and Technology and PCAST s co-chairman, said the country needed to improve its R D effort, especially in relation to the challenge of responding responsibly and cost-effectively to the risk of global climate change from society s greenhouse gas emissions, in particular, carbon dioxide from combustion of fossil fuels. ... 

Fossil fuels release energy in combustion reactions, which ideally produce only CO2 and H2O. The production of CO2 has become a major issue that involves science and public policy because of concerns that increasing concentrations of atmospheric CO2 are causing global climate changes. We will discuss the environmental aspects of atmospheric CO2 in Chapter 18. 

Global climate change has been identified as perhaps the most important environmental issue of this century." Greenhouse gas emissions are not exactly the same as combusted fossil fuel emissions, because several noncombustion gases can contribute to global climate change as well. For example,... 

The other major problems associated with fossil fuel use stem from the products of combustion. The chemical equations shown for fossil fuel combustion all produce cartxM dioxide and water. However, these equations represent the reactions under ideal conditions and do not account for impurities in the fuel, side reactions, and incomplete combustion. When these are taken into account, we can identify three major awiron-mental problems associated with the emissitxis of fossil fuel combustion air pollution, acid rain, and global climate change. We discussed acid rain in Chjpter 3 (see Chemistry in the Environment Acid Rain in Section 3.6). Here we will address air pollution and global climate change, which we first touched on in Section 4.1. 

In addition to their limited supply, the products of the combustion of fossil fuels—directly or indirectly formed—contribute to environmental problems including air pollution, acid rain, and global climate change, which involves an increase in Earth s average temperature caused by CO2 emission. 

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