Real-world vehicle emissions: a summary of the twelfth Coordinating Research Council On-Road Vehicle Emissions Workshop

The Coordinating Research Council (CRC) held its 12th workshop in April 2002, with nearly 90 presentations on the most recent on-road vehicle emissions research. This paper summarizes the presentations from researchers who are engaged in improving understanding of the contribution of mobile sources to air quality. Participants in the workshop discussed mobile source emission models and emission inventories, results from gas- and particle-phase emissions studies from spark-ignition and diesel-powered vehicles (with an emphasis in this workshop on particle emissions), effects of fuels on emissions, evaluation of in-use emissions control programs, and efforts to improve our capabilities in performing on-board emissions measurements, as well as topics for future research.     

(Not) talking about justice: justice self-recognition and the integration of energy and environmental-social justice into renewable energy siting

Renewable energy often provokes heated debate on climate change, energy security and the local impacts of developments. However, how far such discussions involve thorough and inclusive debate on the energy and environmental-social justice issues associated with renewable energy siting remains ambiguous, particularly where government agendas prioritise renewable energy and planning systems offer limited opportunities for public debate on value-based arguments for and against renewable energy developments. Using the concept of justice self-recognition, we argue for greater attention to public discussion of the justice dimensions of renewable energy to assist in developing mechanisms to integrate distributive and procedural fairness principles into renewable energy decision-making. To explore how justice is currently invoked in such contexts, we examine recent U.K. policies for renewable energy and public submissions to applications for small-scale wind energy projects in Cornwall, U.K. The analysis of public comments revealed that justice concerns were rarely discussed explicitly. Comments instead did not raise concerns as justice issues or focused implicitly on distributive justice, stressing local aesthetic, community and economic impacts, clean energy and climate change. However, the findings indicated limited discussion of procedural or participatory justice, an absence that hampers the establishment of coherent procedures for deciding acceptable impacts, information standards, public participation and arbitrating disputes. We conclude by suggesting procedural reforms to policy and planning to enable greater public expression of justice concerns and debate on how to negotiate tensions between energy and environmental-social justice in renewable energy siting decisions.     

Development and Use of a Disaggregated Emissions Inventory for Air Quality Planning in Washington,DC

The Metropolitan Washington Council of Governments (COG) is responsible for developing an Air Quality Plan which will produce attainment of the O₃ and 8 h CO standards in the Washington area by 1987. In order to define as precisely as possible the sources of emissions in the area, a disaggregated emissions inventory was prepared. For mobile sources, this included classification of vehicle type, portion of the trip cycle, and purpose of trip. For nonhighway sources, individual source types were identified. All emissions were assigned to 5 km × 5 km grids and summed to obtain local, state, and/or regional totals. The inventory, although expensive and time-consuming, is a useful tool for decision makers who are responsible for implementing measures to control emissions.     

Colonization and extinction in dynamic habitats: an occupancy approach for a Great Plains stream fish assemblage

Despite the importance of habitat in determining species distribution and persistence, habitat dynamics are rarely modeled in studies of metapopulations. We used an integrated habitat-occupancy model to simultaneously quantify habitat change, site fidelity, and local colonization and extinction rates for larvae of a suite of Great Plains stream fishes in the Arikaree River, eastern Colorado, USA, across three years. Sites were located along a gradient of flow intermittency and groundwater connectivity. Hydrology varied across years: the first and third being relatively wet and the second dry. Despite hydrologic variation, our results indicated that site suitability was random from one year to the next. Occupancy probabilities were also independent of previous habitat and occupancy state for most species, indicating little site fidelity. Climate and groundwater connectivity were important drivers of local extinction and colonization, but the importance of groundwater differed between periods. Across species, site extinction probabilities were highest during the transition from wet to dry conditions (range: 0.52-0.98), and the effect of groundwater was apparent with higher extinction probabilities for sites not fed by groundwater. Colonization probabilities during this period were relatively low for both previously dry sites (range: 0.02-0.38) and previously wet sites (range: 0.02-0.43). In contrast, no sites dried or remained dry during the transition from dry to wet conditions, yielding lower but still substantial extinction probabilities (range: 0.16-0.63) and higher colonization probabilities (range: 0.06-0.86), with little difference among sites with and without groundwater. This approach of jointly modeling both habitat change and species occupancy will likely be useful to incorporate effects of dynamic habitat on metapopulation processes and to better inform appropriate conservation actions.     

Primary sources of selected POPs: regional and global scale emission inventories

During the last decade, a number of studies have been devoted to the sources and emissions of Persistent Organic Pollutants (POPs) at regional and global scales. While significant improvements in knowledge have been achieved for some pesticides, the quantitative understanding of the emission processes and emission patterns for "non-pesticide" POPs are still considered limited. The key issues remaining for the non-pesticide POPs are in part determined by their general source classification. For industrial chemicals, such as the polychlorinated biphenyls (PCBs), there is considerable uncertainty with respect to the relative importance of atmospheric emissions from various source categories. For PCBs, temperature is discussed as a potential key factor influencing atmospheric emission levels and patterns. When it comes to the unintentional by-products of combustion and industrial processes (PCDD/Fs), there is still a large uncertainty with respect to the relative contribution of emissions from unregulated sources such as backyard barrel burning that requires further consideration and characterisation. For hexachlorobenzene (HCB), the relative importance of primary and secondary atmospheric emissions in controlling current atmospheric concentrations remains one of the key uncertainties. While these and other issues may remain unresolved, knowledge concerning the emissions of POPs is a prerequisite for any attempt to understand and predict the distribution and fate of these chemicals on a regional and global scale as well as to efficiently minimise future environmental burdens.     

Quantifying ‘geographic proximity’: Experiences from the United Kingdom's National Industrial Symbiosis Programme

Geographic proximity is said to be a key characteristic of the resource reuse and recycling practice known as industrial symbiosis. To date, however, proximity of symbiont companies has remained an abstract characteristic. By conducting a statistical analysis of synergies facilitated by the United Kingdom's National Industrial Symbiosis Programme during their first five years of operation, this article attempts to quantify geographic proximity and in the process provide practitioners with an insight into the movement trends of different waste streams. Among other it was found that the median distance materials travelled within a symbiotic relationship is 20.4 miles. It is argued that quantitative information of this form is of practical value for the effective deployment of industrial symbiosis practitioners and wider resource efficiency planning. The results and discussion presented within this article are specific to industrial symbiosis opportunities facilitated within the United Kingdom; the methodology and assessment of resource movement influences are, however, expected to be relevant to all countries in which industrial activity is similarly mature and diversified.     

Making sense of environmental accounting

Much as Total Quality Management (TQM) has helped companies decrease waste and enhance value, environmental accounting offers an approach and a suite of tools that can help organizations improve both environmental quality and bottom-line business performance. Its focus is to bridge the world of finance and economics with the world of environmental management. Companies in all sectors have discovered that they can increase profits by meeting and even surpassing environmental regulations. Through environmental accounting, companies can discover more of these opportunities and, ideally, bring environmental concerns earlier into planning, decision making, and operations. This article introduces environmental accounting and some basic principles that should guide organizations' thinking on environmental accounting and environmental accounting systems. It also describes several different objectives for environmental accounting that imply different requirements and orientations. Although the focus of this article is on environmental accounting as an aspect of forward-looking management and decision making in companies, much of the discussion applies to nonprofits and government units as well.     

Environmental accounting—making it work for your company

There is no simple recipe for success in implementing environmental accounting. Day-to-day needs and strategic objectives will determine how an organization can benefit from environmental accounting. Our previous article listed many potential applications of environmental accounting and discussed common environmental accounting objectives.¹ This article is geared toward organizations that want to start implementing environmental accounting and create a foundation of success on which to build. In this context, the questions are (1) What are some logical starting points? and (2) Where do companies go from there? This article first describes some paradigms that may guide companies as they think about how to implement environmental accounting, then it presents a series of critical activities that are needed to make environmental accounting an integral part of ongoing business management functions.     

Atmospheric concentrations and dry and wet deposits of some herbicides currently used on the Canadian Prairies

High volume air sampling in the Canadian Prairies was used to characterize atmospheric concentrations for 10 herbicides (alachlor, atrazine, ethalfluralin, metolachlor, 2,4-D, dicamba, bromoxynil, MCPA, trifluralin, and triallate) along a 500-km north-south transect. Atmospheric concentration measurements at various altitudes identified that of the six herbicides present in the highest concentrations, triallate was strongly influenced by local sources, while 2,4-D, dicamba, bromoxynil, MCPA and trifluralin were dominated by regional atmospheric transport. Concentrations of the herbicides measured at various altitudes were compared with dry deposition rates measured using a dry/wet deposition sampler and used to calculate deposition velocities V(d). The primary atmospheric transport mechanism for MCPA and bromoxynil was shown to be adsorption to particles dispersed in the atmosphere, with the same mechanism also confirmed for 2,4-D and dicamba, while trifluralin was shown to be transported mainly in the gas phase. This method of calculation indicated that transportation of triallate was influenced by particle adsorption. Weekly maximum atmospheric loadings of the major herbicides present in the Prairies were estimated to range from 73 kg for trifluralin to 541 kg for 2,4-D.     

Otolith analysis of juvenile walleye pollock Theragra chalcogramma from the western Gulf of Alaska

Growth rate and hatch date distributions were estimated for juvenile walleye pollock Theragra chalcogramma (Pallas, 1814) collected in autumn 1987 from the western Gulf of Alaska. Mean juvenile growth rates varied geographically by as much as 45%. A trend for slower growth around Unimak Pass and the Shumagin Islands and faster growth upstream in the Alaska Coastal Current towards Kodiak Island was noted; the fastest growth did not occur in the main habitat region. Juvenile hatch date distributions were compared to identify regional differences that might reflect stock structure. Juvenile hatch dates were compared with hatch dates of the same cohort sampled as larvae to test for selective mortality. Regional differences in hatch dates, along with other information, indicated several minor spawning populations located around Kodiak Island and near Unimak Pass. For the main aggregation of pollock in the Shumagin Island region, hatch date distributions were not significantly different among the early larval cohort sampled in late May, the late larvae sampled in mid-June to early July, and the juveniles sampled in autumn. Neither growth-rate nor size-dependent mortality of pollock between the larval and juvenile stages appears to be a dominant factor in determining survival patterns. An alternative test was attempted, by which lengths-at-age during larval life were back-calculated from juvenile otoliths and compared with lengths-at-age of the population sampled as larvae in May and June. Pollock surviving as juveniles in autumn were not larger as larvae than the general larval population. This result is an example of the observation that back-calculated lengths are almost always smaller than the lengths of fish sampled at age (Lee's phenomenon). Problems in determining survival patterns based on otolith back-calculations and comparison of hatch date distributions are discussed.