Acid deposition and the associated particulate nitrates and sulfates are implicated in the deterioration of certain sensitive ecosystems, decreased visibility, negative human health effects, and increased degradation of certain stone building materials and cultural resources, especially those made of limestone and marble. Fine particulate nitrate and sulfate particles associated with acid deposition are implicated in aggravating cardiorespiratory diseases such as asthma and chronic bronchitis, especially in urban areas. In many cases estimating the impact of acid deposition on various ecosystems can be a difficult process because acid deposition is only one of many impacts that can effect a response. However, wet and dry acid deposition has been documented as a major factor in the following ecosystem responses. (more…)

Although some scientists and critics still dispute that human caused greenhouse gases are causing climate change, the majority of scientists and climate experts assert that global warming is a serious problem that could have devastating consequences unless action is taken to reduce fossil fuel emissions. In 2007, for example, the Nobel Prize–winning Intergovernmental Panel on Climate Change (IPCC), a scientific body charged by the United Nations with summarizing the best climate science, concludes that evidence of the warming of our climate is “unequivocal.” (more…)

Electric utility deregulation offers the great promise of market forces leading to lower electric rates, lower air pollution environment, greater energy (and economic) efficiency, and perhaps greater use of renewable energy sources. Ideally, deregulation involves the restructuring of a previously monopolized or nationalized electric utility into separate generation, transmission, distribution, and marketing companies, and allowing wholesale and retail choice of generation company or power marketer. Deregulation has occurred to varying degrees since 1989 in the United Kingdom, Norway, Australia, New Zealand, Chile, Argentina, and about 20 states in the United States. There have been promising results in a few countries and in some U.S. states in some respects, especially lower rates and lower air pollution problems. In most cases, competitive markets have yet to be realized and lower rates can be attributed to other causes, such as previously planned amortization or retirement of expensive power plants, unexpected surplus in natural gas, rate caps, etc. In addition, deregulation has had only a slight beneficial effect on the use of renewable electricity sources. The promise of electric utility deregulation is thus unfulfilled and deserves further study.

Geopolitical considerations have played a major role in many renewable energy policy decisions, e.g., in domestic debates over gasoline taxes, pipeline construction, radioactive waste disposal, and acid rain control legislation in the United States, and in petroleumrelated violence in Nigeria. The most prominent role for geopolitics in energy policy has probably involved international discussions on controlling greenhouse gas emissions, and in oil markets. In the cases of the Kyoto Protocol of 1997 and the 1992 Framework Convention on Climate Change, nations carefully considered their national economic interests, domestic politics, and international trade during the negotiations. European countries, with the lowest rates of population and economic growth along with strong domestic environmental lobbies, have pursued a greater rate of greenhouse gas reduction.

The United States, in contrast, has been stubbornly cautious and backed out of the treaty in 2001 (arguing it is not in its economic best interests), and the oil-rich nations of the Middle East have been least supportive of any emissions controls. In the case of oil markets, with the United States now dependent on imports for over half its supply, energy policy and trade strategy have played major roles in the pursuit of new oil discoveries in Alaska and in warfare in Kuwait, Iraq, and perhaps Afghanistan.

Reductions in carbon intensity, C/E, the carbon emitted per unit of energy generated, reflect the degree to which societies decarbonize their energy sources. The long-term trend has been a shift from coal to oil to natural gas––hydrocarbons with decreasing C/H ratios emitting progressively less CO2 per joule. However, the increasing use of clean low-carbon fuels is not sustainable without somehow disposing of excess carbon because it opposes the trend in the abundance of fossil fuels, with coal resources being the most abundant followed by oil and gas. (more…)

Scientists study Earth’s climate not just from observation but also from a theoretical perspective. Modern-day climate models successfully reproduce the key features of Earth’s climate, including the variations in wind patterns around the globe, the major ocean current systems such as the Gulf Stream, and the seasonal changes in temperature and rainfall associated with Earth’s annual revolution around the sun. The models also reproduce some of the more complex natural oscillations of the climate system. Just as the atmosphere displays random day-to-day variability that we term “weather,” the climate system produces its own random variations, on timescales of years. (more…)

air pollution problems created by coal combustion. Meanwhile, coal-fired power plants and industrial boilers spewed out tons of gaseous and particulate pollutants into the atmo- sphere. During combustion, the small amounts of sulfur and nitrogen in coal combine with oxygen to form sulfur dioxide (SO2), sulfur trioxide (SO3), and the oxides of nitrogen (NOx). (more…)

Smoke from biomass and coal combustion contains a large number of pollutants with known health hazards, including particulate matter, carbon monoxide, nitrogen dioxide, sulfur oxides (mainly from coal), formaldehyde, and polycyclic organic compounds (e.g., carcinogens such as benzo[a]pyrene). The concentrations of each of these pollutants vary among the different forms of solid fuels, with animal dung and crop residues having some of the highest level emissions to environment of particulate matter, one of the important indicator pollutants for health effects. (more…)

Addressing global warming, however, is a highly complex and daunting endeavor. Many climate experts have urged the world to stabilize greenhouse gas concentrations in the atmosphere around 450 to 550 parts per million (ppm)—that is, no more than 450 to 550 units of greenhouse gases for every million units of air in the earth’s atmosphere. This approach, experts say, could keep average global temperatures at no more than 3.6° Fahrenheit (2° Celsius) above preindustrial levels, which could avoid some of the worst, irreversible consequences of climate change. (more…)

Options for dealing with the threats of climate change include both adaptation to inevitable changes and mitigation, or lessening, of those changes that we can still affect. One possible adaptation would be to adjust our agricultural practices to the changing regional patterns of temperature and rainfall. Another would be to build coastal defenses against the inundation from sea-level rise. Only mitigation, however, can prevent the most threatening changes. (more…)

Still hotly debated by some, human-induced global warming is now accepted in the scientific community. Earth’s average yearly temperature is getting steadily warmer; sea levels are rising due to melting ice caps; and the resulting impact on ocean life, wildlife, and human life is already evident. The human-induced buildup of greenhouse gases in the atmosphere poses serious and diverse threats to life on earth. As scientists work to develop accurate models to predict the future impact of global earth warming, researchers, policy makers, and industry leaders are coming to terms with what can be done today to halt and reverse the human contributions to global climate change impact.

In the “business as usual” emissions scenario, climate change will have an array of substantial impacts on our society and the environment by the end of this century. Patterns of rainfall and drought are projected to shift in such a way that some regions currently stressed for water resources, such as the desert southwest of the United States and the Middle East, are likely to become drier. More intense rainfall events in other regions, such as Europe and the mid-western United States, could lead to increased flooding. Heat waves like the one in Europe in summer 2003, which killed more than thirty thousand people, are projected to become far more common. Atlantic hurricanes are likely to reach greater intensities, potentially doing far more damage to coastal infrastructure.

Furthermore, regions such as the Arctic are expected to warm faster than the rest of the globe. Disappearing Arctic sea ice already threatens wildlife, including polar bears and walruses. Given another 2°C warming (3.6°F), a substantial portion of the Greenland ice sheet is likely to melt. This event, combined with other factors, could lead to more than 1 meter (about 3 feet) of sea-level rise by the end of the century. Such a rise in sea level would threaten many American East Coast and Gulf Coast cities, as well as low-lying coastal regions and islands around the world. Food production in tropical regions, already insufficient to meet the needs of some populations, will probably decrease with future greenhouse global warming. Thee incidence of infectious disease is expected to increase in higher elevations and in latitudes with long term warming temperatures. In short, the impacts of future climate change are likely to have a devastating impact on society and our environment in the absence of intervention.