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利用博罗县城自动监测站2015年的环境空气自动监测数据,分析了实施《环境空气质量标准》(GB3095-2012)对博罗县城空气质量评价的影响.研究发现,若采用新标准,博罗县城空气中PM2.5和O3将出现不同程度的超标,达标率从99.4%下降到88.5%;PM2.5和O3的纳入是导致空气质量达标率下降的最主要原因,NO2标准的收严和CO的纳入未对博罗县城空气质量评价造成影响. 相似文献
894.
A Nationwide Analysis of U.S. Army Corps of Engineers Reservoir Performance in Meeting Operational Targets
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Lauren A. Patterson Martin W. Doyle 《Journal of the American Water Resources Association》2018,54(2):543-564
The United States (U.S.) Army Corps of Engineers operates reservoirs across the U.S. with 89% of reservoirs constructed prior to 1980. Many reservoirs have experienced changes in environmental conditions (e.g., climate and sediment yield) and societal conditions (e.g., water/energy demand and ecological flows) since construction. These changes may challenge the potential for reservoirs to meet their operational targets (OTs) (management goals). Historic daily reservoir data and OTs were collected for 233 reservoirs. Analyses were developed to identify when and where reservoirs may be systematically departing from OTs in terms of the frequency and magnitude of departure. Fifty‐six percent of reservoirs consistently met operating targets, 30% were borderline, and 13% experienced frequent and large magnitude departures. Fifty‐two percent of reservoirs with large departures were due to shortages and were located in the South Pacific and Southwestern divisions. This work provides a framework to identify reservoir performance in relation to management goals, a necessary step for moving toward adaptive management under changing conditions. All individual reservoir analyses are provided via an interactive data visualization tool: https://nicholasinstitute.duke.edu/reservoir-data . 相似文献
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Michael A. Souffront Alcantara Christian Kesler Michael J. Stealey E. James Nelson Daniel P. Ames Norm L. Jones 《Journal of the American Water Resources Association》2018,54(4):859-871
Hydrologic modeling can be used to provide warnings before, and to support operations during and after floods. Recent technological advances have increased our ability to create hydrologic models over large areas. In the United States (U.S.), a new National Water Model (NWM) that generates hydrologic variables at a national scale was released in August 2016. This model represents a substantial step forward in our ability to predict hydrologic events in a consistent fashion across the entire U.S. Nevertheless, for these hydrologic results to be effectively communicated, they need to be put in context and be presented in a way that is straightforward and facilitates management‐related decisions. The large amounts of data produced by the NWM present one of the major challenges to fulfill this goal. We created a cyberinfrastructure to store NWM results, “accessibility” web applications to retrieve NWM results, and a REST API to access NWM results programmatically. To demonstrate the utility of this cyberinfrastructure, we created additional web apps that illustrate how to use our REST API and communicate hydrologic forecasts with the aid of dynamic flood maps. This work offers a starting point for the development of a more comprehensive toolset to validate the NWM while also improving the ability to access and visualize NWM forecasts, and develop additional national‐scale‐derived products such as flood maps. 相似文献
897.
Evaluation of Satellite‐Derived Rainfall Data for Multiple Physio‐Climatic Regions in the Santiago River Basin,Mexico
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J.R. Ávila‐Carrasco H.E. Júnez‐Ferreira P.H. Gowda J.L. Steiner D.N. Moriasi P.J. Starks J. Gonzalez A.A. Villalobos C. Bautista‐Capetillo 《Journal of the American Water Resources Association》2018,54(5):1068-1086
Assessment of water resources requires reliable rainfall data, and rain gauge networks may not provide adequate spatial representation due to limited point measurements. The Tropical Rainfall Measuring Mission (TRMM) provides rainfall data at global scale, and has been used with good results. However, TRMM data are an indirect measurement of rainfall, and therefore must be validated for its proper use. In this work, a validation scheme was designed and implemented to compare the TRMM Version 7 (V7) monthly rainfall product at different time frames with data measured in two hydrologic subregions of the Santiago River Basin (SRB) in Mexico: Río Alto Santiago and Río Bajo Santiago (RBS). Additionally, three physio‐climatic regions provide an assessment of the interplay of topography, distance from coastal regions, and seasonal weather patterns on the correspondence between both datasets. The TRMM V7 rainfall product exhibited good agreement with the rain gauge data particularly for the RBS and for the whole SRB during wettest summer and autumn seasons. However, strong regional dependence was observed due to differences in climate and topography. Overall, in spite of some noted underestimations, the monthly TRMM V7 rainfall product was found to provide useful information that can be used to complement limited monitoring as is the case of RBS. An improved combined rainfall product could be generated and thus gaining the most benefits from both data sources. 相似文献
898.
James W. N. Steenberg Pamela J. Robinson Andrew A. Millward 《Journal of Environmental Planning and Management》2018,61(3):553-567
Urban forest ecosystems are complex and vulnerable social–ecological systems. The relationship between urban forests and housing is particularly variable and uncertain. We examine the influence of building renovation and rental housing on public trees at the parcel and street-section scale in a residential neighbourhood in Toronto, Canada. We use empirical data describing multiple tree inventories and government open data describing building permit applications to test for effects on urban forest structure, tree mortality, and tree planting. We found that the presence and number of building permits significantly predicted mortality at both scales, while planting was positively correlated with building permits at the street-section scale only. Multi-unit parcels had significantly lower rates of planting than single-unit parcels and multi-unit housing was positively correlated with mortality at the street-section scale. These findings suggest that where concentrated changes in housing stock are occurring, substantial losses of trees and associated ecosystem services are possible. 相似文献
899.
为探究人口规模、收入水平、消费倾向、节能政策和技术等因素对中国城镇生活能源消费的影响,基于拓展的STIRPAT模型并运用2000~2013年中国省际面板数据对各影响因素的效应进行评估。结果显示:城镇生活能源强度、城镇居民消费倾向、人均可支配收入、城镇化率、总人口、政策综合力度6个因素的增长率每变化1%,将会引起城镇生活能源消费量增长率0.9322%、0.8537%、(0.559 2+0.169 2 ln DI)%、0.599 8%、0.408 0%、-0.012 0%的变化,表明除节能政策外,其余5因素均正向促进城镇生活能耗增长。其中生活能源强度对城镇生活能耗影响最大,节能政策虽会抑制城镇生活能耗增长,但作用较为微弱。政府需继续加强节能政策综合实施力度,从而实现生活能源消费领域的节能减排。 相似文献
900.
David R. Maidment 《Journal of the American Water Resources Association》2017,53(2):245-257
The National Flood Interoperability Experiment is a research collaboration among academia, National Oceanic and Atmospheric Administration National Weather Service, and government and commercial partners to advance the application of the National Water Model for flood forecasting. In preparation for a Summer Institute at the National Water Center in June‐July 2015, a demonstration version of a near real‐time, high spatial resolution flood forecasting model was developed for the continental United States. The river and stream network was divided into 2.7 million reaches using the National Hydrography Dataset Plus geospatial dataset and it was demonstrated that the runoff into these stream reaches and the discharge within them could be computed in 10 min at the Texas Advanced Computing Center. This study presents a conceptual framework to connect information from high‐resolution flood forecasting with real‐time observations and flood inundation mapping and planning for local flood emergency response. 相似文献