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51.
This research presents a method to determine the maximum potential for the capturing of solar radiation on the rooftop of buildings in an urban environment. This involves the modeling of solar energy potential and comparison to historical building energy demand profiles through the use of 3-D solar simulation software tools and geographic information systems (GIS). The objective is to accurately identify the amount of surface area that is suitable for solar photovoltaic (PV) installations and to estimate the hourly PV electricity generation potential of existing building rooftops in an urban environment. This study demonstrates a viable approach for modeling urban solar energy and offers valuable information for electricity distributors, policy makers, and urban energy planners to facilitate the substantial design of a green built environment. The developed methodology is comprised of three main sections: (1) determination of suitable rooftop area, (2) determination of the amount of incident solar radiation available per rooftop, and (3) estimation of hourly solar PV electricity generation potential. A case study was performed using this method for Ryerson University, located in Toronto, Canada. It was found that solar PV could supply up to 19% of the study area’s electricity demands during peak consumption hours. The potential benefits of solar PV was also estimated based upon hourly greenhouse gas emission intensity factors as well as Time-of-Use (TOU) savings through the Ontario Feed-in-Tariff (FIT) program, which allows for better representation of the positive impacts of solar technologies. 相似文献
52.
Geographical areas constitute the basic implementation locus for integrated coastal zone management strategies and activities.
Because the definition of territorial planning objectives may be affected by socioeconomic and environmental characteristics,
one of the main steps in the process involves dividing the coast into homogeneous environmental management units (HEMUs).
This article presents a general and simple method for regionalizing the landside of a coastal zone into HEMUs and illustrates
it through application to the Catalan coast. Socioeconomic and natural (biophysical) subsystems were selected as the most
appropriate dimensions of the regionalization process. Dimensions were described using 11 spatial themes, which were managed
in a geographic information system environment that proved to be an adequate tool for the purpose. A final coastal zone map
of four classes of HEMUs connected to local administrative units was obtained, and because it reflects the current natural
and socioeconomic dynamics, it can be considered as an initial step in the planning process for the Catalan coast. Although
the proposed method was developed based on the characteristics of the Catalan coast, it is general enough to be adapted and
applied to most developed or developing coastal areas. 相似文献
53.
54.
本文主要是围绕地表水环境遥感检测展开讨论,全面介绍了水环境检测的关键技术和系统,建立改进双峰法的水体分布遥感提取方法,并以具体地区为例进行分析,采用不同方法建立解析方法,从根本上提升反演方法的区域和积极适用性,希望能够对相关人员起到参考性价值。 相似文献
55.
本文首先分析了生态环境信息化体系的主要构成要素,其后基于大数据技术的生态环境信息化体系重点领域应用进行了深入研究。 相似文献
56.
Julia Metag Michaela Maier Tobias Füchslin Laurits Bromme Mike S. Schäfer 《Environmental Communication: A Journal of Nature and Culture》2018,12(8):1077-1094
ABSTRACTCitizens’ attitudes toward science are related to their use of science-related information from various sources. Evidence is scarce regarding citizens’ individual media repertoires for staying informed about science as segmentation studies so far have primarily focused on scientific attitudes. In this paper, we explore audience segments regarding their science-related information behavior and whether such segments are comparable or vary between two countries with similar information environments. Based on two surveys in Switzerland and Germany, we identify national audience segments that differ in their science-related information repertoires, and analyze their sociodemographic characteristics and science-related attitudes. In both countries, we find very comparable information user segments ranging from those who inform themselves frequently about science (“Active Seekers”/“Science Consumers”) to those who hardly get in contact with any information about science and research (“Non-Users”). Those segments which get in contact with information about science frequently show generally more positive attitudes. 相似文献
57.
58.
Luca Coscieme Federico M. Pulselli Simone Bastianoni Christopher D. Elvidge Sharolyn Anderson Paul C. Sutton 《Ambio》2014,43(7):969-979
Night-time satellite imagery enables the measurement, visualization, and mapping of energy consumption in an area. In this paper, an index of the “sum of lights” as observed by night-time satellite imagery within national boundaries is compared with the emergy of the nations. Emergy is a measure of the solar energy equivalent used, directly or indirectly, to support the processes that characterize the economic activity in a country. Emergy has renewable and non-renewable components. Our results show that the non-renewable component of national emergy use is positively correlated with night-time satellite imagery. This relationship can be used to produce emergy density maps which enable the incorporation of spatially explicit representations of emergy in geographic information systems. The region of Abruzzo (Italy) is used to demonstrate this relationship as a spatially disaggregate case. 相似文献
59.
This study projected responses of forest net primary productivity (NPP) to three climate change scenarios at a resolution
of 5 km × 5 km across the state of Louisiana, USA. In addition, we assessed uncertainties associated with the NPP projection
at the grid and state levels. Climate data of the scenarios were derived from Community Climate System Model outputs. Changes
in annual NPP between 2000 and 2050 were projected with the forest ecosystem model PnET-II. Results showed that forest productivity
would increase under climate change scenarios A1B and A2, but with scenario B1, it would peak during 2011–2020 and then decline.
The projected average NPP under B1 over the years from 2000 to 2050 was significantly different from those under A1B and A2.
Forest NPP appeared to be primarily a function of temperature, not precipitation. Uncertainties of the NPP projection were
due to large spatial resolution of the climate variables. Overall, this study suggested that in order to project effects of
climate change on forest ecosystem at regional level, modeling uncertainties could be reduced by increasing the spatial resolution
of the climate projections. 相似文献
60.
Contaminants in the coastal karst aquifer system along the Caribbean coast of the Yucatan Peninsula, Mexico 总被引:1,自引:0,他引:1
Metcalfe CD Beddows PA Bouchot GG Metcalfe TL Li H Van Lavieren H 《Environmental pollution (Barking, Essex : 1987)》2011,159(4):991-997
Intensive land development as a result of the rapidly growing tourism industry in the “Riviera Maya” region of the Yucatan Peninsula, Mexico may result in contamination of groundwater resources that eventually discharge into Caribbean coastal ecosystems. We deployed two types of passive sampling devices into groundwater flowing through cave systems below two communities to evaluate concentrations of contaminants and to indicate the possible sources. Pharmaceuticals and personal care products accumulated in the samplers could only have originated from domestic sewage. PAHs indicated contamination by runoff from highways and other impermeable surfaces and chlorophenoxy herbicides accumulated in samplers deployed near a golf course indicated that pesticide applications to turf are a source of contamination. Prevention and mitigation measures are needed to ensure that expanding development does not impact the marine environment and human health, thus damaging the tourism-based economy of the region. 相似文献