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The seemingly irresistible growth of motorised transport and its environmental effects have led the NRP to also put mobility and transport (M & T) on its agenda. NRP questions are focused on psychosocial factors and mechanisms underlying the popularity of motorised transport, and on technical as well as behavioural measures and strategies to reduce global air pollution stemming from mobility and the use of motor vehicles. In Phase 1 of the programme, five NRP-funded Mssss & T projects have been conducted. Together with one or two related projects, these will be briefly summarised and commented upon. General observations, conclusions and some suggestions will be provided at the end of this paper.
The primary supposition about renewable forms of energy is that use of such resources will not result in depletion or exhaustion. While it is true that natural energy flows such as sun and wind are not directly subject to degradation by use, there may still be indirect limitations on renewability. The exploitation of natural energy flows may require that systems of nonrenewable "support" resources be used to capture, store, and convert natural energy into useful forms. Poor resource management practices that degrade the support resources may therefore, in effect, endanger renewability. Biomass is an illustrative case of a renewable energy resource with nonrenewable support components. The soil and water management...
The primary supposition about renewable forms of energy is that use of such resources will not result in depletion or exhaustion. While it is true that natural energy flows such as sun and wind are not directly subject to degradation by use, there may still be indirect limitations on renewability. The exploitation of natural energy flows may require that systems of nonrenewable "support" resources be used to capture, store, and convert natural energy into useful forms. Poor resource management practices that degrade the support resources may therefore, in effect, endanger renewability. Biomass is an illustrative case of a renewable energy resource with nonrenewable support components. The soil and water management...
Developing an energy policy from a collection of programs is made more complicated because there is no single value that can be used as a best estimate of the contribution of a single policy, despite the ability to estimate the impact Of the complete suite. In this paper we illustrate the problem and use cooperative game theory to show one way to estimate individual effects of a policy goal in the context of collective estimates. Using an economic equilibrium model, we illustrate the behavior of four policies, namely, a gasoline tax, CAFE standards, a carbon tax, and drilling the Arctic National Wildlife Reserve, through their Shapley value contributions in measuring the impact of each in the context of a suite...
The rates and styles of channel adjustments following an abrupt and voluminous sediment pulse are investigated in the context of site and valley characteristics and time-varying sediment transport regimes. Approximately 10.5 x 106m3 of stored gravel and sand was exposed when Barlin Dam failed during Typhoon WeiPa in 2007. The dam was located on the Dahan River, Taiwan, a system characterized by steep river gradients, typhoon- and monsoon-driven hydrology, high, episodic sediment supply, and highly variable hydraulic conditions. Topography, bulk sediment samples, aerial photos, and simulated hydraulic conditions are analyzed to investigate temporal and spatial patterns in morphology and likely sediment transport...
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Data collected from a comprehensive set of hydrodynamic experiments conducted with live grass carp eggs and larvae, to evaluate drifting and swimming patterns with 3 different in-stream obstructions: (1) a gravel bump, (2) a single cylinder, and (3) submerged vegetation. The hydrodynamic behavior of eggs and larvae with each obstruction was continuously monitored for about 85 consecutive hours. Transient spatial distributions of the locations of eggs and larvae across the water column were generated for each flow scenario.
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These data represent input and estimates from a medium-resolution (1:100,000 scale) NHDPlus SPAtially Referenced Regression on Watershed attributes (SPARROW) model for the Chesapeake Bay watershed (CBSS_v2). The model spatially correlates long-term mean annual suspended-sediment flux in 113 non-tidal streams to likely upland and stream-corridor sources, landscape factors affecting upland sediment transport and delivery to stream corridors, and fluvial and reservoir retention representing the early 2000 time period. The item COMID is a common related field between the data file and the spatial component (catchments) in NHDPlus version 1.0.
Off-farm work is a growing reality in the US agricultural sector as a whole. Another staple program in the US agriculture is the use of crop insurance. This paper assesses hitherto unaddressed issues of fuel consumption and hence pollution generated by farm households associated with off-farm work and crop insurance. We applied a quantile regression method on a unique national farm-level survey data to address the fuel consumption issues. Results indicate that off-farm work by operators tends to decrease fuel expenses. In contrast, households with crop insurance had higher fuel consumption thereby increasing fuel usage. Finally, our study shows that the net effect of these two activities resulted in an increase...
P>1. Habitats are often connected by fluxes of energy and nutrients across their boundaries. For example, headwater streams are linked to surrounding riparian vegetation through invertebrate and leaf litter inputs, and there is evidence that consumers in downstream habitats are subsidised by resources flowing from headwater systems. However, the strength of these linkages and the manner in which potential headwater subsidies vary along climatic and disturbance gradients are unknown. 2. We quantified the downstream transport of invertebrates, organic matter and inorganic sediment from 60 fishless headwater streams in the Wenatchee River Basin located on the eastern slope of the Cascade Range in Washington, U.S.A....
European Union countries’ current energy policies for the transport sector promote, amongst other initiatives; urban mobility plans, the renewal of fleets of cars and industrial vehicles and the introduction of biofuel. From the point of view of eco-efficiency and Life Cycle Assessment (LCA), energy policies must go further. The objective of this paper is to analyse the current transport model and the policies on energy efficiency being promoted in the EU from a LCA point of view. Special attention has been paid to private vehicles, in assessing the environmental impact of the various stages of manufacture, their use and disposal, and the consequences of plans to renew fleets. How old should a vehicle ideally be...
Plug-in hybrid electric vehicles (PHEVs) have the potential to be an economic means of reducing direct (or tailpipe) carbon dioxide (CO2) emissions from the transportation sector However, without a Climate policy that places a limit on CO2 emissions from the electric generation sector, the net impact of widespread deployment of PFIEVs on overall US CO2 emissions is not as clear. A comprehensive analysis must consider jointly the transportation and electricity sectors. along with feedbacks to the rest of the energy system. In this paper, we use the Pacific Northwest National Laboratory's MiniCAM model to perform an integrated economic analysis of the penetration of PFIEVs and the resulting impact oil total U.S. CO2...
Goodstein identified and discussed a "Saturday effect" in data on the timing of tanker oil spills. This comment describes two ways in which the validity of the statistical analysis used to identify and confirm this effect can be strengthened.
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Cette couche SIG représente l'ensemble des routes couvrant le territoire de la République centrafricaine. Elle a été réalisée par le Projet des Forets d'Afrique (FORAF). FORAF a combiné 2 couches SIG : 1- Le réseau de routes couvrant tout le pays et réalisé par le Projet d'aménagement des ressources naturelles en République centrafricaine (PARN) en 1990 ; 2- Le réseau de routes couvrant la zone forestière uniquement(au Sud-Ouest), réalisé par le Projet d'appui à la réalisation des plans d'aménagement forestiers (PARPAF) en 2007. Le PARPAF a digitalisé les routes forestières couvrant la zone forestière sur images satellites Landsat (2002-2003). Digitalisées individuellement par permis forestier, les routes ont...
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Cette couche SIG représente l'ensemble des routes couvrant le territoire de la République centrafricaine. Elle a été réalisée par le Projet des Forets d'Afrique (FORAF). FORAF a combiné 2 couches SIG : 1- Le réseau de routes couvrant tout le pays et réalisé par le Projet d'aménagement des ressources naturelles en République centrafricaine (PARN) en 1990 ; 2- Le réseau de routes couvrant la zone forestière uniquement(au Sud-Ouest), réalisé par le Projet d'appui à la réalisation des plans d'aménagement forestiers (PARPAF) en 2007. Le PARPAF a digitalisé les routes forestières couvrant la zone forestière sur images satellites Landsat (2002-2003). Digitalisées individuellement par permis forestier, les routes ont...
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The base for this dataset was provided by Belize's Department of Civil Aviation via a document named "Aerodromes in Belize" (May 2005). This layer depicts the locations of the 38 extant airstrips / airports, including six facilities which have ceased operation. In addition to locational information, parameters provided in this dataset also include detailed physical descriptions of each "aerodrome" (dimensions/ surface material / elevation above mean sea level / magnetic orientation) and tenure information.
Regional transport of water and dissolved constituents through heavily regulated river systems is influenced by the presence of reservoirs. Analysis of seasonal patterns in solute fluxes for salinity and nutrients indicates that in-reservoir processes within large storage reservoirs in the Rio Grande and Colorado basins (southwestern USA) are superimposed over the underlying watershed processes that predominate in relatively unregulated stream reaches. Connectivity of the aquatic system with the landscape is apparently disrupted by processes within the reservoir systems; these processes result in large changes in characteristics for solute transport that persist downstream in the absence of significant inputs. Additionally,...
Two field studies revealed large differences among various subgroups in the population of car drivers. Private drivers, commuters, and business drivers differed strongly with respect to current decisions and behaviour which affect CO2 emissions, and with respect to their sensitivity to various policy instruments. Several promising policy targets were identified" combinations of user groups and behaviours where substantial CO2 reduction may be achieved. The sensitivity of different car user groups to various policy measures showed whether and how desired behavioral changes may be realised.
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Cette couche SIG représente l'ensemble des routes couvrant le territoire de la République centrafricaine. Elle a été réalisée par le Projet des Forets d'Afrique (FORAF). FORAF a combiné 2 couches SIG : 1- Le réseau de routes couvrant tout le pays et réalisé par le Projet d'aménagement des ressources naturelles en République centrafricaine (PARN) en 1990 ; 2- Le réseau de routes couvrant la zone forestière uniquement(au Sud-Ouest), réalisé par le Projet d'appui à la réalisation des plans d'aménagement forestiers (PARPAF) en 2007. Le PARPAF a digitalisé les routes forestières couvrant la zone forestière sur images satellites Landsat (2002-2003). Digitalisées individuellement par permis forestier, les routes ont...
In the UK market, the total price of renewable electricity is made up of the Renewables Obligation Certificate and the price achieved for the electricity. Accurate forecasting improves the price if electricity is traded via the power exchange. In order to understand the size of wind farm for which short-term forecasting becomes economically viable, we develop a model for wind energy. Simulations were carried out for 2003 electricity prices for different forecast accuracies and strategies. The results indicate that it is possible to increase the price obtained by around £5/MWh which is about 14% of the electricity price in 2003 and about 6% of the total price. We show that the economic benefit of using short-term...
map background search result map search result map Proposed Road Framework Routes secondaires de la République centrafricaine (secondary roads of Central African Republic) Routes principales de la République centrafricaine (Main roads of Central African Republic) Pistes d'exploitation forestiere de la République centrafricaine (Logging Roads) Belize Airstrips Input and predictions from a suspended-sediment SPARROW model CBSS_V2 in the Chesapeake Bay watershed Belize Airstrips Proposed Road Framework Input and predictions from a suspended-sediment SPARROW model CBSS_V2 in the Chesapeake Bay watershed Routes secondaires de la République centrafricaine (secondary roads of Central African Republic) Routes principales de la République centrafricaine (Main roads of Central African Republic) Pistes d'exploitation forestiere de la République centrafricaine (Logging Roads)