Using prognostic model-generated meteorological output in the AERMOD dispersion model: an illustrative application in Philadelphia, PA

In this study, we introduce the prospect of using prognostic model-generated meteorological output as input to steady-state dispersion models by identifying possible advantages and disadvantages and by presenting a comparative analysis. Because output from prognostic meteorological models is now routinely available and is used for Eulerian and Lagrangian air quality modeling applications, we explore the possibility of using such data in lieu of traditional National Weather Service (NWS) data for dispersion models. We apply these data in an urban application where comparisons can be made between the two meteorological input data types. Using the U.S. Environment Protection Agency's American Meteorological Society/U.S. Environmental Protection Agency Regulatory Model (AERMOD) air quality dispersion model, hourly and annual average concentrations of benzene are estimated for the Philadelphia, PA, area using both hourly MM5 model-generated meteorological output and meteorological data taken from the NWS site at the Philadelphia International Airport. Our intent is to stimulate a discussion of the relevant issues and inspire future work that examines many of the questions raised in this paper.     

依据(代)生物体对化学品的反应预测对生态系统服务功能的影响

保护生态系统服务功能越来越多地被作为风险评估的目标,但是目前生态风险评估的终点和评估生态系统服务功能受到的潜在影响之间有很大的差距。作者提出了一个框架,将常用的生态毒理学终点与对种群和群落的影响以及生态系统的服务功能联系起来。这个框架建立在机制效应模型的长足进步上,这些模型旨在跨越多种生物组织,并解释各种生物相互作用和反馈。为了说明这一点,作者引入了2个研究案例,它们采用了已完善和已验证的机制效应模型：鱼种群的inSTREAM个体模型和AQUATOX生态系统模型。他们还展示了动态能量平衡理论可以为解释组织级毒性提供一种通用货币。他们认为,一个基于机制模型的框架,可以预测化学品暴露对生态系统服务的影响,再结合经济估值,可以为环境管理提供一种有用的方法。作者强调了使用这个框架的潜在好处以及未来工作中需要解决的挑战。
精选自Forbes, V. E., Salice, C. J., Birnir, B., Bruins, R. J.F., Calow, P., Ducrot, V., Galic, N., Garber, K., Harvey, B. C., Jager, H., Kanarek, A., Pastorok, R., Railsback, S. F., Rebarber, R. and Thorbek, P. (2017), A framework for predicting impacts on ecosystem services from (sub)organismal responses to chemicals. Environmental Toxicology and Chemistry, 36: 845–859. doi: 10.1002/etc.3720
详情请见http://onlinelibrary.wiley.com/doi/10.1002/etc.3720/full
     

Modeling to Evaluate Contribution of Oil and Gas Emissions to Air Pollution

Oil and gas production in the Western United States has increased considerably over the past 10 years. While many of the still limited oil and gas impact assessments have focused on potential human health impacts, the typically remote locations of production in the Intermountain West suggests that the impacts of oil and gas production on national parks and wilderness areas (Class I and II areas) could also be important. To evaluate this, we utilize the Comprehensive Air quality Model with Extensions (CAMx) with a year-long modeling episode representing the best available representation of 2011 meteorology and emissions for the Western United States. The model inputs for the 2011 episodes were generated as part of the Three State Air Quality Study (3SAQS). The study includes a detailed assessment of oil and gas (O&G) emissions in Western States. The year-long modeling episode was run both with and without emissions from O&G production. The difference between these two runs provides an estimate of the contribution of the O&G production to air quality. These data were used to assess the contribution of O&G to the 8 hour average ozone concentrations, daily and annual fine particulate concentrations, annual nitrogen deposition totals and visibility in the modeling domain. We present the results for the Class I and II areas in the Western United States. Modeling results suggest that emissions from O&G activity are having a negative impact on air quality and ecosystem health in our National Parks and Class I areas.

Implications: In this research, we use a modeling framework developed for oil and gas evaluation in the western United States to determine the modeled impacts of emissions associated with oil and gas production on air pollution metrics. We show that oil and gas production may have a significant negative impact on air quality and ecosystem health in some national parks and other Class I areas in the western United States. Our findings are of particular interest to federal land managers as well as regulators in states heavy in oil and gas production as they consider control strategies to reduce the impact of development.     

Analysis of Ozone and Nitric Oxide by a Chemiluminescent Method in Laboratory and Atmospheric Studies of Photochemical Smog

A prototype instrument monitoring ozone or nitric oxide has been used for photochemical smog studies in the laboratory and the atmosphere. The principle of the detector is based on the chemiluminescent reaction     

Emission Characteristics of Mexico City Vehicles

The University of Denver remote sensor for automobile exhaust was set up for nine days at five locations in the Mexico City area. A total of 31,838 valid readings for CO and HC emissions were obtained. The emissions distribution was unlike any other we have observed in North America or Europe, in that the emissions for both CO and HC were vastly greater than seen elsewhere. The readings are discussed in terms of the fraction of CO and HC which would be measured by a tailpipe probe, and in terms of grams emitted per gallon of gasoline. The median CO emission was 3.8 percent, with half of the CO emissions coming from the 24 percent of the fleet with over 6.6 percent CO in the exhaust. The median HC emission was 1,100 parts per million measured as propane equivalent, while half the emissions come from twelve percent of the fleet with more than 4,000 ppm propane equivalent in the exhaust.     

Uncertainties in PM2.5 gravimetric and speciation measurements and what we can learn from them

The U.S. Environmental Protection Agency (EPA) and the federal land management community (National Park Service, United States Fish and Wildlife Service, United States Forest Service, and Bureau of Land Management) operate extensive particle speciation monitoring networks that are similar in design but are operated for different objectives. Compliance (mass only) monitoring is also carried out using federal reference method (FRM) criteria at approximately 1000 sites. The Chemical Speciation Network (CSN) consists of approximately 50 long-term-trend sites, with about another 250 sites that have been or are currently operated by state and local agencies. The sites are located in urban or suburban settings. The Interagency Monitoring of Protected Visual Environments (IMPROVE) monitoring network consists of about 181 sites, approximately 170 of which are in nonurban areas. Each monitoring approach has its own inherent monitoring limitations and biases. Determination of gravimetric mass has both negative and positive artifacts. Ammonium nitrate and other semivolatiles are lost during sampling, whereas, on the other hand, measured mass includes particle-bound water. Furthermore, some species may react with atmospheric gases, further increasing the positive mass artifact. Estimating aerosol species concentrations requires assumptions concerning the chemical form of various molecular compounds, such as nitrates and sulfates, and organic material and soil composition. Comparing data collected in the various monitoring networks allows for assessing uncertainties and biases associated with both negative and positive artifacts of gravimetric mass determinations, assumptions of chemical composition, and biases between different sampler technologies. All these biases are shown to have systematic seasonal characteristics. Unaccounted-for particle-bound water tends to be higher in the summer, as does nitrate volatilization. The ratio of particle organic mass divided by organic carbon mass (Roc) is higher during summer and lower during the winter seasons in both CSN and IMPROVE networks, and Roc is lower in urban than non-urban environments.     

Racial differences in promotion candidate performance and reactions to selection procedures: a field study in a diverse top‐management context

The present study examined African‐American and White promotion candidates' reactions to and performance on selection procedures that were completed within a police department where African Americans occupied the majority of top‐management positions. Reactions (perceived job relatedness and test‐taking motivation) of 187 candidates competing for promotion to the rank of sergeant were assessed after completing a written job knowledge test and a situational interview. Analyses showed that both the African‐American and White candidates judged the situational interview to be more job‐related than the pencil‐and‐paper job knowledge test. In addition, African Americans perceived both selection measures to be more job‐related and reported higher levels of test‐taking motivation than White candidates even though African Americans performed more poorly than White candidates on the paper‐and‐pencil test. These results challenge the contention that lower test‐taking motivation for African‐American candidates is related to racial differences in performance on pencil‐ and‐paper tests. Implications and directions for future research on reactions to selection procedures for promotion in racially diverse employment settings are discussed. Copyright © 2007 John Wiley & Sons, Ltd.     

Measuring good governance: piloting an instrument for evaluating good governance principles

ABSTRACT

As federal, state, and local governments and agencies respond to calls to make decisions and implement programs according to tenets of ‘good governance’, a need exists to develop methods for systematically evaluating performance. ‘Good governance’ has been characterized as including a wide array of principles, which vary across literatures. Comparatively little scholarship has sought to systematically quantify program achievement in accordance with these principles. We develop and present a scale for measuring program achievement in accordance with eight main principles of good governance: inclusivity, fairness, transparency, accountability, legitimacy, direction, performance, and capability. We present the results of a pilot implementation of the scale within the context of two community-based deer management programs. Our results suggest that these principles of good governance may not sort into distinct dimensions in a real-world context.