Annual Review of Environment and Resources - Volume 29, 2004

The effect of anthropogenic emissions from activities, such as fossil-fuel, biomass, and biofuel burning; transportation; and land-clearing; have a profound impact on the climate system. The impact of these activities is manifested in observed changes in temperature, precipitation, sea-level rise, melting of glaciers, air quality, health, and agriculture yields, to name a few. The obvious question to ask is the role that these different processes play in affecting climate and what action could one impose to curtail or constrain adverse human impacts on climate. Greenhouse gases have long been studied, as they play a major role in changing climate. But over the past 10–20 years, aerosols have emerged as the other big contenders in climate change studies. This review focuses on the current understanding of the effects of aerosols on climate, with an emphasis on the thermodynamical and indirect aerosol effects. We also examine available measurements that could be used to decipher the aerosol influence on climate, with an outlook on how the uncertainties in aerosol effects may impact future climate predictions and policy changes.

The movement of individuals defines a spatial neighborhood that can help determine marine management strategies. Here, I briefly review four fields of marine biology that each differentially illuminate the scale of marine neighborhoods: effects of marine reserves, tagging studies, microchemistry, and population genetics. These suggest adult neighborhood sizes for many demersal fish and invertebrates as small as kilometers and up to 10 to 100 km. Larval dispersal may be shorter than previously suspected: neighborhood sizes of 10 to 100 km for invertebrates and 50 to 200 km for fish are common in current compilations.

How can small reserves protect such species? One conceptual framework is to set reserve size based on adult neighborhood sizes of highly fished species and determine spacing of a reserve network based on larval neighborhoods. The multispecies nature of fisheries demands that network designs accommodate different life histories and take into account the way local human communities use marine resources.

The modern technological society mobilizes and uses a very large number of materials. These substances are derived from rocks, sediments, and other natural repositories, and most undergo transformation prior to use. A large fraction of the materials is eventually returned to the environment. Natural processes do the same but not necessarily with the same suite of materials. For purposes of better understanding industrial development and potential environmental impact, it is important to know, even approximately, the elemental cycles of all materials potentially useful for modern technology. In this review, we examine and summarize cycle information for 77 of the first 92 elements in the periodic table. Mobilization calculations demonstrate that human activities likely dominate or strongly perturb the cycles of most of the elements other than the alkalis, alkali earths, and halogens. We propose that this pattern is ultimately related to the aqueous solubilities of the predominant chemical forms of the elements as they occur in nature: Human action dominates the cycles of the elements whose usual forms are highly insoluble, nature those that are highly soluble. Examples of the utility of anthropogenically dominated cycle determinations for resource supply analyses, environmental impact assessment, and public policy are presented and discussed. If the rapid rise in the use of materials by the technological society in the twentieth century continues into the next century, anthropogenic dominance of the cycling of a majority of the elements of the periodic table will only increase.

Carbon capture and storage (CCS) technologies remove carbon dioxide from flue gases for storage in geologic formations or the ocean. We find that CCS is technically feasible, with current costs of about $200 to $250 per ton of carbon. Although currently a relatively expensive mitigation option, CCS could be attractive if we have a stringent carbon policy, if CCS turns out unexpectedly inexpensive relative to other options, or if it is otherwise desired to retain fossil fuels as part of the energy mix while reducing carbon emissions. Near-term prospects favor CCS for electric power plants and certain industrial sources with storage in depleted oil and gas reservoirs as opposed to aquifers. Deep aquifers may provide an attractive longer-term-storage option, whereas ocean storage poses greater technical and environmental uncertainty. CCS should be seriously considered for addressing climate change, alongside energy efficiency and carbon-free energy, although significant environmental, technical, and political uncertainties and obstacles remain.

Plant genetic resources provide the biological underpinning for agriculture and food production. No nation is independent in terms of these resources. Interdependence levels are high among countries. Policy impediments to access may subside, increasing already substantial germplasm flows. Serious questions exist, however, about the health and availability of the actual resources. Genebank collections contain many unintended duplicates, making aggregate numbers seem larger than they really are. Information about individual accessions, particularly those found in situ, is often poor, reducing frequency and efficiency of use and ultimate benefits. Although not firmly established today, the link between conservation and use must be strengthened.

No other industry in the United States uses more materials by weight than the construction industry. Because of its economic strength and societal importance, it is also a significant polluter and a target of growing stakeholder scrutiny. This review offers an extended, supply chain inclusive framework for the study of the construction industry that serves all the life-cycle stages of society's infrastructure systems, and it summarizes selected literature on the life-cycle environmental assessment of construction materials, designs, and processes. On the basis of identified knowledge gaps, a research agenda is discussed for lesser-studied questions in order to first understand and then eventually reduce the environmental impacts of construction materials, processes, and activities.

This review critically surveys an extensive literature on mining, development, and environment. It identifies a significant broadening over time in the scope of the environment question as it relates to mining, from concerns about landscape aesthetics and pollution to ecosystem health, sustainable development, and indigenous rights. A typology compares and contrasts four distinctive approaches to this question: (a) technology and management-centered accounts, defining the issue in terms of environmental performance; (b) public policy studies on the design of effective institutions for capturing benefits and allocating costs of resource development; (c) structural political economy, highlighting themes of external control, resource rights, and environmental justice; and (d) cultural studies, which illustrate how mining exemplifies many of society's anxieties about the social and environmental effects of industrialization and globalization. Each approach is examined in detail.

Managed grazing covers more than 25% of the global land surface and has a larger geographic extent than any other form of land use. Grazing systems persist under marginal bioclimatic and edaphic conditions of different biomes, leading to the emergence of three regional syndromes inherent to global grazing: desertification, woody encroachment, and deforestation. These syndromes have widespread but differential effects on the structure, biogeochemistry, hydrology, and biosphere-atmosphere exchange of grazed ecosystems. In combination, these three syndromes represent a major component of global environmental change.

We review the economics of electricity generated, or conserved, from a diverse range of fossil-fuel, nuclear, and renewable energy sources and energy efficiency options. At the same time, we survey the methods used to compute the costs of generated and delivered electricity and power, including bus bar costs; wholesale and retail marketplace costs; life-cycle accounting systems; premiums associated with political, social, and environmental risks; costs that reflect explicit and implicit subsidies; costs inclusive of externalities calculated by a variety of means; and net costs, including a range of proposed and potential environmental tax regimes. These diverse and at times conflicting analytic methods reflect a wide range of assumptions and biases in how the inputs for energy generation as well as how the subsidies and social and environmental costs are computed or, is often the case, neglected. This review and tutorial provides side-by-side comparisons of these methods, international cost comparisons, as well as analysis of the magnitude and effects of a range of technological, market-based, and subsidy-driven costs on the final price of electricity. Comparability of costs between supply and conservation technologies and methods in the energy sector has consistently been a problem, and the diversity of energy cost accounting schemes provides significant opportunity for very different arguments to be made for specific technologies, regulatory and market regimes, and a wide range of social and environmental taxes. We provide a review of the tools and a commentary on how these methods are used to determine the cost of energy services. The conclusion contains an analysis of how these methods of energy valuation are similar, how they differ, as well as an analysis of the explicit and implicit assumptions that underlie each approach.

New energy efficiency policies have been introduced around the world. Historically, most energy models were reasonably equipped to assess the impact of classical policies, such as a subsidy or change in taxation. However, these tools are often insufficient to assess the impact of alternative policy instruments. We evaluate the so-called engineering economic models used to assess future industrial energy use. Engineering economic models include the level of detail commonly needed to model the new types of policies considered. We explore approaches to improve the realism and policy relevance of engineering economic modeling frameworks. We also explore solutions to strengthen the policy usefulness of engineering economic analysis that can be built from a framework of multidisciplinary cooperation. The review discusses the main modeling approaches currently used and evaluates the weaknesses in current models. We focus on the needs to further improve the models. We identify research priorities for the modeling framework, technology representation in models, policy evaluation, and modeling of decision-making behavior.

Energy and energy technologies have a central role in social and economic development at all scales, from household and community to regional and national. Among its welfare effects, energy is closely linked with public health both positively and negatively, the latter through environmental pollution and degradation. We review the current research on how energy use and energy technologies influence public health, emphasizing the risks associated with indoor and ambient air pollution from energy use, and the links between the local and global environmental health impacts of energy use. This review illustrates that, despite their large public health implications, most energy policies and programs in the developing world are fundamentally treated as components of overall economic development, without explicit assessment of their health benefits or hazards. Closer integration of health in energy management can facilitate the development of policies and programs that increase welfare and minimize negative health outcomes. Renewable energy technologies are used as an example of how an integrated energy-health approach can be used in policy analysis and formulation.

Concerns about safeguarding key infrastructures (such as energy, communications, banking, and roads) from deliberate attack are long-standing, but since the end to the cold war, emphasis has turned to the possible impacts of terrorism. Activities to address these concerns are sometimes called critical infrastructure protection (CIP), a concept that is somewhat different from the one of “energy security,” which focuses on politically and economically motivated supply interruptions. Different elements of the energy infrastructure are characterized by distinct vulnerabilities. Breaches of security in nuclear plants can lead to large-scale environmental disasters—but the infrastructure is concentrated and relatively easy to guard. Oil and gas production, transportation, and refining infrastructures are often spatially concentrated, and disruptions can lead to shortages if supply is not restored before stockpiles are exhausted. Traditional electricity infrastructures suffer from the need for system-wide integrity to ensure supply reliability, having critical facilities spatially concentrated (substations), and insignificant storage capacity for emergency supply. This review discusses how energy infrastructure and security are related, how this relationship differs from traditional energy security concepts, and what it may mean for private and policy decisions. Key concepts include redundancy, diversity, resilience, storage, decentralization, and interdependence. The concept of CIP is still relatively new and is likely to evolve over time, possibly away from a “guards, gates, and guns” defensive approach and toward a design approach that yields systems that are inherently harder to successfully attack. Such survivable systems may feature distributed intelligence, control, and operations.