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1.
W. Earl Bardsley 《Natural Resources Research》2008,17(4):197-204
A sustainable global silicon energy economy is proposed as a potential alternative to the hydrogen economy. This first visualization
of a silicon energy economy is based on large-scale and carbon-neutral metallic silicon production from major smelters in
North Africa and elsewhere, supplied by desert silica sand and electricity from extensive solar generating systems. The resulting
“fuel silicon” is shipped around the world to emission-free silicon power stations for either immediate electricity generation
or stockpiling. The high energy density of silicon and its stable storage make it an ideal material for maintaining national
economic functioning through security of base load power supply from a renewable source. This contrasts with the present situation
of fossil fuel usage with its associated global warming and geopolitical supply uncertainties. Critical technological requirements
for the silicon economy are carbon-neutral silicon production and the development of efficient silicon-fired power stations
capable of high-temperature rapid oxidation of fuel silicon. A call is made for the development of research effort into these
specific engineering issues, and also with respect to large-scale economical solar power generation. 相似文献
2.
RALPH DUBAYAH PAUL M. RICH 《International journal of geographical information science》2013,27(4):405-419
Abstract Incident solar radiation at the Earth's surface is the result of a complex interaction of energy between the atmosphere and the surface. Recently much progress has been made towards the creation of accurate, physically-based solar radiation formulations that can model this interaction over topographic and other surfaces (such as plant canopies) for a large range of spatial and temporal scales. In this paper we summarize our current work on solar radiation models and their implementation within both GIS and image processing systems. An overview of the effects of topography and plant canopies on solar radiation is presented along with a discussion of various options for obtaining the data necessary to drive specific solar radiation models. Examples are given from our own work using two models, ATM (Atmospheric and Topographic Model), a model based within an image processing framework, and SOLARFLUX, a GIS-based model. We consider issues of design, including GIS implementation and interface, computational problems, and error propagation. 相似文献
3.
State Geography Standards in 2004 总被引：1，自引：1，他引：0
《The Journal of geography》2012,111(4):182-184
Abstract National Geography Standards for the middle school years generally stress the teaching of latitude and longitude. There are many creative ways to explain the great grid that encircles our planet, but the author has found that students in his college-level geography courses especially enjoy human-interest stories associated with lines of latitude and longitude. In particular, certain nautical “rites of passage” and GPS-enabled adventure show how some people identify with these imaginary lines as places to celebrate and explore. The author contends that humanizing this global geometry enhances student understanding and appreciation at any grade level. 相似文献
4.
中国能源-粮食生产对水资源竞争的关系——基于水足迹的视角 总被引：2，自引：0，他引：2
通过对水-能源-粮食系统的定量分析,能更好的探究三者之间的协同作用,对提高区域资源综合利用效率、促进区域可持续发展具有重要意义。本文基于水足迹视角探讨了1990—2017年中国31个地区能源-粮食生产对水资源的竞争关系,并借助ESTDA模型框架对其时空动态特征进行分析。结果表明：① 中国化石能源水足迹的时间演变特征可分为缓慢下降-快速上升-平稳下降3个阶段,其中化石能源灰水足迹平均占化石能源水足迹的70%以上;电力水足迹呈持续上升态势,其中电力蓝水足迹平均占电力水足迹的70%以上;粮食蓝水足迹上升幅度明显,平均占农业用水总量的70%以上。② 能源-粮食水足迹总量空间分布格局受区域资源禀赋差异影响较大。③ 时间序列上,中国能源-粮食生产对水资源竞争指数呈逐年上升态势;空间分布上,同时兼顾能源生产与粮食生产的黄河中下游区、东北地区为竞争指数高值集聚区,其余地区竞争指数相对较小。④ LISA时间路径分析显示,中国南方地区能源-粮食水资源竞争指数的空间格局的稳定性比北方更强;各地区在不同程度上均受局部结构的时空依赖效应影响;竞争指数空间格局变化具有较强的整合性且空间凝聚性较强。⑤ 能源-粮食生产对水资源的竞争在短期内难以得到有效缓解。 相似文献
5.
Ole Humlum Birger Ulf Hansen Niels Nielsen Hanne H. Christiansen 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(1):113-121
An automatic meteorological station has been operating at the Arctic Station (69°15'N, 53°31'W) in West Greenland since 1990. This paper summarises meteorological parameters during 1998, including snow cover, ground temperatures and active layer development, and presents comments on the local permafrost thickness. Abstract Active layer monitoring in Greenland was started in 1996 and 1997, and forms part of the Circumpolar Active Layer Monitoring (CALM) Network of the International Permafrost Association (IPA). The results of the first years of this monitoring of thaw progression and maximum active layer thickness in two Greenlandic permafrost areas are presented. Two sites are in the continuous permafrost zone at Zackenberg in NE Greenland (74 °N), and one at Disko Island in W Greenland (69 °N), at the border between discontinuous and continuous permafrost. The data collected at Zackenberg demonstrate interannual variation in the timing of thaw progression in the monitoring grid holding a seasonal snowpatch, while there is less variation in the horizontal grid without a snowpatch. The maximum active layer thickness for the two Zackenberg grids is more or less consistent for the first three years with averages from 58 to 66 cm in mid and late August. At Disko the active layer reached 71 cm in mid August 1998. Spatially the distribution of the maximum, annual active layer thickness within the grids is concordant. 相似文献
6.
POH-CHIN LAI 《International journal of geographical information science》2013,27(4):329-345
Abstract In the face of limited and declining budgets, the estimation of costs involved in implementing a geographical information system (GIS) deserves attention. One of the major procedures inherent in the use of GIS is the task of digitizing existing maps. This step is not only the first but may also occur at various stages of the implementation. There is, however, a lack of information on the cost of digitizing. This paper identifies the costs of an intensive effort at manual digitizing over a period of eleven months using the ARC/INFO GIS on a Prime 9650 mini-computer. General costs for digitizing one layer of information from a U.S. Geological Survey 1:24 000 quadrangle are derived. Although the results are based on factors which are unique to this study, the author believes that the findings provide useful bases for estimating costs of digitizing. 相似文献
7.
Nowadays, increased attention is being paid to the causal relationship between electricity consumption and economic growth. This paper attempts to examine the causal relationship between electricity consumption and economic growth for China’s Beijing-Tianjin-Hebei agglomeration, using annual data covering the period 1982- 2008. In this study, unit root tests, the Johansen co-integration test, and the Granger causality test are applied. The empirical results indicate that the two series (electricity consumption and economic growth) of the three locales (Beijing, Tianjin, and Hebei) are non-stationary. But first differences of the two series are stationary. The results of the Johansen co-integration test indicate that electricity consumption and economic growth are co-integrated in Hebei and Tianjin while this is not the case in Beijing. The Granger causality test implies that there is causality running from electricity consumption to economic growth in all of the three locales. Causality running from economic growth to electricity consumption is found in Hebei and Beijing while this is not the case in Tianjin. This means that an increase in electricity consumption directly affects economic growth and that economic growth also stimulates further electricity consumption in Hebei and Beijing. But in Tianjin, an increase in electricity consumption directly affects economic growth while economic growth cannot affect electricity consumption. These findings can provide useful information for local governments of the three locales to formulate sustainable energy and economic policies. The study is of great significance for circular economy and building a resource-conserving society. 相似文献
8.
The continuing use of petrochemicals in mineral nitrogen (N) production may be affected by supply or cost issues and climate agreements. Without mineral N, a larger area of cropland is required to produce the same amount of food, impacting biodiversity. Alternative N sources include solar and wind to power the Haber-Bosch process, and the organic options such as green manures, marine algae and aquatic azolla. Solar power was the most land-efficient renewable source of N, with using a tenth as much land as wind energy, and at least 100th as much land as organic sources of N. In this paper, we developed a decision tree to locate these different sources of N at a global scale, or the first time taking into account their spatial footprint and the impact on terrestrial biodiversity while avoiding impact on albedo and cropland, based on global resource and impact datasets. This produced relatively few areas suitable for solar power in the western Americas, central southern Africa, eastern Asia and southern Australia, with areas most suited to wind at more extreme latitudes. Only about 2% of existing solar power stations are in very suitable locations. In regions such as coastal north Africa and central Asia where solar power is less accessible due to lack of farm income, green manures could be used, however, due to their very large spatial footprint only a small area of low productivity and low biodiversity was suitable for this option. Europe in particular faces challenges because it has access to a relatively small area which is suitable for solar or wind power. If we are to make informed decisions about the sourcing of alternative N supplies in the future, and our energy supply more generally, a decision-making mechanism is needed to take global considerations into account in regional land-use planning. 相似文献
9.
电力资源在中国能源建设以及能源发展方式转变中处于中心地位,全面降低电力强度是实现资源、经济、环境可持续发展的关键所在。研究中国电力强度重心迁移路径以及区域差异可以厘清电力强度分布状况,对实现上述目标具有现实意义。本文运用重心理论研究了中国1985-2014年电力强度重心迁移路径,进而采用泰尔指数计算并分解了电力强度非均衡程度。研究结果表明：1985-2014年,电力强度总体上呈现出持续向西迁移的态势。期间,1985-1993、2003-2014年主要体现为向西北方向移动,1993-2003年则表现为向西南方向移动的特征。1985-2000年,区域间及区域内部差异对于重心迁移的贡献率各占50%;2000-2014年,演变推力主要来源于区域内部差异,贡献率均值为54.49%,内部差异则受西北、西南、华北地区影响最大。 相似文献
10.
ZHANGLei DanielTODD XIEHui CHENWenyan WUYingmei JIANGWei 《地理学报(英文版)》2005,15(1):61-70
Greenhouse-gas (GHG) emissions in China have aroused much interest, and not least in recent evidence of their reduction. Our intent is to place that reduction in a larger context, that of the process of industrialization. A lengthy time perspective is combined with a cross-sectional approachChina plus five other countries-and addressed through two general models. The findings are salutary. First, they suggest that a diversified economic structure is consistent with diminished intensity in energy use. Secondly, and the obverse of the first, they imply that a diversified energy structure promotes reductions in CO2 emissions. Finally, one is led inevitably to the conclusion that, together, the findings point to a path for countries to transform their economies while at the same time undertaking to drastically moderate their energy use, switching from a pattern of heavy carbon emissions to one in which lighter carbon emissions prevail. The implications of such findings for environmental management are enormous. 相似文献
11.
《The Journal of geography》2012,111(5):195-202
Abstract This article addresses the lack of outcome-based research on the integration of technology into pedagogy at the undergraduate college level. It describes a study performed at a Midwestern university, testing the relative effectiveness of paper and electronic topographic maps for teaching map-reading skills, and considers the relationship between learning styles and paper or digital map preference. Results indicate that, although student map skill performance did not differ significantly with the use of paper or electronic maps, students preferred paper maps. Neither their performance nor their preferences were related to learning style. The article discusses the significance of these findings. 相似文献
12.
《The Journal of geography》2012,111(2):47-56
Abstract The end of the twentieth century was characterized by a surge of interest in the impact of gender on environmental politics. Many people assert that women have a special relationship with the environment, leading to a link being assumed between women and environmental issuses in development planning. This article analyzes this assertion cross-culturally and, using field data from both North America and the global South as illustration, engages with a long-standing set of debates concerning the relationship between agency, structure, knowledge, and power and the ways in which these relationships have been opera-tionalized and conceptualized. 相似文献
13.
David J. Madden 《Urban geography》2019,40(6):888-892
ABSTRACTThis concluding commentary discusses some of the ways in which branded renaming reflects conflicts over ownership, authority, property and power. Practices of sponsored renaming and place branding are not monolithic, but this special issue shows that they are deeply rooted within neoliberal urbanism. It should therefore not be surprising that place branding is almost always contested, and often a flashpoint in struggles over urban space. 相似文献
14.
DAVID MERCER 《The Australian geographer》2003,34(1):91-121
Up until very recently--and in marked contrast to such countries as Spain, Denmark and Germany--Australia generated hardly any electricity from the wind. Driven largely by the mandatory targets embodied in the Renewable Energy (Electricity) Act 2000 (Commonwealth) this situation is now changing. Australia has several operational small- to medium-sized wind energy power stations in Western Australia, Victoria, New South Wales and Queensland. But--in the face of often strong local opposition--the Australian Wind Energy Association is keen to increase the number and scale of such projects. This paper outlines recent overseas developments in wind energy and then focuses on the environmental and planning dilemmas posed by this form of electricity production. Particular attention is focused on a highly controversial wind energy proposal in south-western Victoria, the Portland Wind Energy Project (PWEP). The argument presented is that wind is only one of a number of possible renewable energy options, that coastal landscapes are an 'endangered species', and that it is time for geographers to revisit methodologies concerned with evaluating landscape beauty and debating the place of landscape values within the ecologically sustainable development paradigm. 相似文献
15.
The continuing use of petrochemicals in mineral nitrogen(N) production may be affected by supply or cost issues and climate agreements.Without mineral N,a larger area of cropland is required to produce the same amount of food,impacting biodiversity.Alternative N sources include solar and wind to power the Haber-Bosch process,and the organic options such as green manures,marine algae and aquatic azolla.Solar power was the most land-efficient renewable source of N,with using a tenth as much land as wind energy,and at least 100 th as much land as organic sources of N.In this paper,we developed a decision tree to locate these different sources of N at a global scale,or the first time taking into account their spatial footprint and the impact on terrestrial biodiversity while avoiding impact on albedo and cropland,based on global resource and impact datasets.This produced relatively few areas suitable for solar power in the western Americas,central southern Africa,eastern Asia and southern Australia,with areas most suited to wind at more extreme latitudes.Only about 2% of existing solar power stations are in very suitable locations.In regions such as coastal north Africa and central Asia where solar power is less accessible due to lack of farm income,green manures could be used,however,due to their very large spatial footprint only a small area of low productivity and low biodiversity was suitable for this option.Europe in particular faces challenges because it has access to a relatively small area which is suitable for solar or wind power.If we are to make informed decisions about the sourcing of alternative N supplies in the future,and our energy supply more generally,a decision-making mechanism is needed to take global considerations into account in regional land-use planning. 相似文献
16.
Understanding the energy balance on the Tibetan Plateau is important for better prediction of global climate change. To characterize the energy balance on the Plateau, we examined the radiation balance and the response of albedo to environmental factors above an alpine meadow and an alpine wetland surfaces in the eastern Tibetan Plateau, using 2014 data. Although our two sites belong to the same climatic background, and are close geographically, the annual incident solar radiation at the alpine meadow site(6,447 MJ/(m2·a)) was about 1.1 times that at the alpine wetland site(6,012 MJ/(m2·a)),due to differences in the cloudiness between our two sites. The alpine meadow and the alpine wetland emitted about 38%and 42%, respectively, of annual incident solar radiation back into atmosphere in the form of net longwave radiation; and they reflected about 22% and 18%, respectively, of the annual incident solar radiation back into atmosphere in the form of shortwave radiation. The annual net radiation was 2,648 and 2,544 MJ/(m2·a) for the alpine meadow site and the alpine wetland site, respectively, accounting for only about 40% of the annual incident solar radiation, significantly lower than the global mean. At 30-min scales, surface albedo exponentially decreases with the increase of the solar elevation angle; and it linearly decreases with the increase of soil-water content for our two sites. But those relationships are significantly influenced by cloudiness and are site-specific. 相似文献
17.
ABSTRACT Composition and richness of coastal vegetation differs with distance from the water and sheltering by topography. Transition from pioneer beach plants to mature forests is expected to be narrow on low wave energy coasts with a tropical climate favorable to vegetation growth. The goal of this paper is to determine whether vegetation on the beach and foredune will be denser and have a greater number of species and more woody shrubs near the water as wave and wind stresses diminish because of favorable shoreline orientation within a pocket beach. Field data on beach width, beach mobility, dune height, vegetation species, vegetation height and percent vegetation cover were collected in Puerto Rico along six cross-shore transects. Beaches are more stable at transects in the lee of an eolianite barrier and a tombolo. The vegetation gradient there is compressed, with denser, taller, more diverse vegetation and more tree species close to the waterline than at more exposed sites. The lack of mobility of the beaches and dunes and lack of geomorphically significant disturbance events is in contrast to the conspicuous feedbacks between overwash, topography, and vegetation on exposed mid-latitude coasts, revealing the need for more study of low-energy beach environments. 相似文献
18.
《The Professional geographer》2012,64(1):9-21
Desalination is an increasingly important water source for the sunny, arid city of El Paso, Texas. As the city’s population grows, El Paso Water, the city’s water utility, has had to drill deeper into the Hueco Bolson aquifer, a primary water source for El Paso. This deeper drilling into the Hueco Bolson, however, has yielded progressively more saline water. In response, El Paso Water and administrators from Fort Bliss jointly constructed a reverse osmosis desalination plant to protect the Hueco Bolson’s freshwater supplies and expand the city’s water sources. Reverse osmosis water desalination, however, is an expensive, energy-intensive process currently dependent on carbon-heavy fossil fuels. Solar energy, however, is an abundant, carbon-free energy source that could potentially reduce the energy costs and carbon footprint of the reverse osmosis desalination process. We hypothesize that building a solar microgrid that supplies El Paso’s desalination plant with energy in tandem with the regional grid will reduce the plant’s energy expenditures in the long term compared to solely buying energy from the regional grid. We used the Hybrid Optimization for Multiple Energy Resources (HOMER) model created by the National Renewable Energy Laboratory. The results suggest that a solar microgrid whose modules use one axis tracker could reduce the plant’s energy expenses. Key Words: desalination, solar energy, water resources. 相似文献
19.
Deborah Feder 《The Professional geographer》2004,56(2):185-200
The production and use of fossil fuels and nonrenewable electricity creates many forms of environmental degradation. To reduce degradation, this research suggests an energy strategy based on energy end‐use analysis and regional geography. Energy end‐use analysis and regional geography are used to match renewable energy resources with site‐specific, end‐use needs. Fieldwork conducted within Centre County, Pennsylvania, demonstrates that small‐scale solar, wind, and micro‐hydropower resources could displace a proportion of household electricity use. Such an approach meets energy end‐use needs, while conserving fossil fuels and reducing environmental degradation. 相似文献
20.
AbstractScholarship on collaboration in natural resource management is restricted by a lack of large-N assessments and mixed methods approach to examine relationships between collaborative structures and processes, and management actions and outcomes. This paper examines the relationship between perceived levels of collaboration, collaborative process indicators, and benefits of USDA Forest Service stewardship contracts at a broad spatial and temporal scale using mixed methodology. This study found higher levels of collaboration were strongly associated with jointly initiated processes that included a breadth of interests and utilized a broad range of outreach mechanisms and opportunities for engagement. Highly collaborative processes were closely linked with attaining project objectives and social and economic benefits. Findings contribute to defining collaboration by uncovering the relationship between perceived levels of collaboration, the role of process characteristics, and perceived benefits of collaborative stewardship contracting processes through a large-N dataset (n?=?1,064) and case study (n?=?61) findings. 相似文献