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1.
Nuclear power plants are normally assumed to be safe when their radiation impact in all operational states is kept at a reasonably
low level. However, accidentally released radioactive substances and ionizing radiation may lead to a situation that cannot
maintain the regulatory prescribed dose limits for internal and external exposure of the personnel and population. Nuclear
emergency preparedness and response in nuclear or radiological events have been of concern recently in international communities.
Nuclear power plants may need to provide essential information regarding possible scenarios of accidental releases that might
have short-term detrimental effects and long-term risks in nearby populated regions. This paper presents a synergistic integration
of a source term model and a three-dimensional, time-dependent, numerical model (i.e., HOTMAC/RAPTAD), which was applied to
simulate a specific scenario in which a vapor cloud was accidentally released from Maanshan (i.e., the third nuclear power
plant) in South Taiwan. It aims at dealing with middle-range risk assessment for nuclear emergency preparedness and response.
The solutions of such an integrated modeling platform can be found with numerical analyses that describe the processes of
radionuclide generation, transport, decay, and deposition, giving the final risk assessment in a neighboring coastal city—Kaohsiung,
South Taiwan. In addition, sensitivity analyses were performed to evaluate the internal consistency of model parameters, which
further support the application potentials. Such a modeling technique is valuable because it can characterize the fate and
transport of radioactive nuclides over the long term. The case study in South Taiwan uniquely demonstrates the feasibility
and significance of such model integration. 相似文献
2.
The analysis of data of the ground-level ozone concentration and accumulated ozone exposure over a threshold of 40 ppb (AOT40)
in the rural areas of Lithuania is presented. Trends in the annual ozone mean, 95{th} and 25{th} percentiles were determined
as statistically not significant at Preila and Rugsteliskes sites during the 1994hbox{–}2004 period. Trends in the ozone concentration
and its percentiles in the air masses arriving to Preila station in “polluted” and “unpolluted” sectors have been examined.
Statistically significant changes in the ozone annual mean and 25th percentile were found in air masses in both “polluted”
and “unpolluted” sectors in the 1988hbox{–}2002 period. The trend analysis in the ozone monthly mean and percentiles for each
month of the year revealed the main changes in the ozone level in both sectors during January-May. Insignificant downward
trends in monthly 95th percentile in “unpolluted” sector and upward trends in “polluted” sector were found during summer months.
Values of AOT40 for the protection of forests as well as crops and semi-natural vegetation were determined during the 1994–2004
period. The estimated AOT40 values for the protection of forests were lower than the critical level at Lithuanian rural sites
but AOT40 values for the protection of crops and semi-natural vegetation were found to be higher than the critical level at
both sites. 相似文献
3.
Negligence to consider the spatial variability of rainfall could result in serious errors in model outputs. The objective
of this study was to examine the uncertainty of both runoff and pollutant transport predictions due to the input errors of
rainfall. This study used synthetic data to represent the “true” rainfall pattern, instead of interpolated precipitation.
It was conducted on a synthetic case area having a total area of 20 km2 with ten subbasins. Each subbasin has one rainfall gauge with synthetic precipitation records. Six rainfall storms with varied
spatial distribution were generated. The average rainfall was obtained from all of the ten gauges by the arithmetic average
method. The input errors of rainfall were induced by the difference between the actual rainfall pattern and estimated average
rainfall. The results show that spatial variability of rainfall can cause uncertainty in modeling outputs of hydrologic, which
would be transport to pollutant export predictions, when uniformity of rainfall is assumed. Since rainfall is essential information
for predicting watershed responses, it is important to consider the properties of rainfall, particularly spatial rainfall
variability, in the application of hydrologic and water quality models. 相似文献
4.
Dere S Dalkiran N Karacaoğlu D Elmaci A Dülger B Sentürk E 《Environmental monitoring and assessment》2006,115(1-3):1-22
The implications of metal contamination of agricultural soils due to long term irrigation with treated industrial wastewater and their subsequent accumulation in the vegetables/crops growing on such soils has been assessed in an area of industrial complex, Jajmau, Kanpur (India). Physico-chemical properties of the soil were also studied. The soil and vegetables/crops were sampled from an area of 2100 acre agricultural land and analyzed for physico-chemical properties and metal accumulation in different parts of the plants. The comparison of the data of physico-chemical properties of control and contaminated soil showed that salinity, electrical conductivity, available phosphorous, sodium and potassium content (both water soluble and exchangeable) were found high in contaminated soil. The analysis of plant available metal content in the soil showed the highest level of Fe, which ranged from 529.02 to 2615 μg g−1 dw and lowest level of Ni (3.12 to 10.51 μg g−1 dw). The analysis of the results revealed that accumulation of toxic metal Cr in leafy vegetables was found more than fruit bearing vegetables/crops. Thus, it is recommended that the leafy vegetables are unsuitable to grow in such contaminated sites. It is important to note that toxic metal, Ni was not detected in all the plants. The edible part of the vegetables (under ground) such as, garlic (19.27 μg g−1 dw), potato (11.81 μg g−1 dw) and turmeric (20.86 μg g−1 dw) has accumulated lowest level of toxic metal, Cr than leafy and fruit bearing vegetables. In some fruit part of vegetables such as, bitter gourd, egg plant, jack tree, maize and okra, the accumulation of Cr was not detected and may be grown in this area. 相似文献
5.
Auto-pollution is the by-product of our mechanized mobility, which adversely affects both plant and human life. However, plants growing in the urban locations provide a great respite to us from the brunt of auto-pollution by absorbing the pollutants at their foliar surface. Foliar surface configuration and biochemical changes in two selected plant species, namely Ficus religiosa L. and Thevetia nerifolia L., growing at IT crossing (highly polluted sites), Picup bhawan crossing (moderately polluted site) and Kukrail Forest Picnic Spot (Low polluted site) were investigated. It was observed that auto-exhaust pollution showed marked alterations in photosynthetic pigments, protein and cysteine contents and also in leaf area and foliar surface architecture of plants growing at HP site as compared to LP site. The changes in the foliar configuration reveal that these plants can be used as biomarkers of auto-pollution. 相似文献
6.
A 2D analytical turbulent diffusion model for particle dispersion and deposition at different heights along the pipe flow
and circumferential deposition has been developed. This liquid–solid turbulent diffusion model presented in this paper has
emanated from an existing gas–liquid turbulent diffusion model. This model can be used as a handy tool for quick estimation
one and two-dimensional deposition fluxes of particles in water distribution networks. A comprehensive 3D numerical investigation
has been carried out using multiphase mixture model available in “Fluent 6.2” to verify the above analytical model. Different
particles sizes and densities were used for 3D numerical investigations. The deposition was studied as a function of particle
diameter, density, and fluid velocity. The deposition of particles, along the periphery of the pipe wall and at different
depths, was investigated. Both the models findings matched with qualitative phenomena such as deposition of heavier particles
at the bottom of the pipe wall were higher at lower velocities and lower at higher velocities. The lighter particles were
found mostly suspended with homogeneous distribution. Smaller particles were also suspended with marginal higher concentration
near the bottom of the pipe wall. This marginal higher concentration of the smaller particles was found to be slightly pronounced
for lower velocity. These analogies of particles are well discussed with the ratio between free-flight velocity and the gravitational
settling velocity. Extended analytical model results were compared with the 3D computational fluid dynamics simulation results.
Discrepancies in the model results were discussed. 相似文献
7.
Evaluation Score and Interpretation Index for the Ecological Quality of Running Waters in Central and Northern Hellas 总被引:3,自引:0,他引:3
The present study aims at creating an evaluation system for the quality of running waters, based on the analysis of benthic
macroinvertebrate records from Hellenic rivers (473 samples from 8 river basins). The proposed evaluation system (Hellenic
Evaluation Score and its Interpretation Index) may be used for waters sampled with the cost effective semi-quantitative sampling
method of “3 min kick-sweep” and requires benthic macroinvertebrates to be identified to the taxonomic level of family. Though
resulting from a modification of the Spanish score BMWP, it differs from it in the following characteristics: a) it includes
the relative abundance of benthic macroinvertebrates and b) it takes into consideration the habitat diversity of the studied
site, classifying it as “poor” or “rich”, based on some parameters of the System B of the Water Framework Directive (2000/60/EU).
Its interpretation is also based on a five-scaled classification system, consistent with the provisions of the same Directive. 相似文献
8.
Rice WE 《Environmental monitoring and assessment》2004,99(1-3):251-257
A sub-surface desert water harvester was constructed in the sagebrush steppe habitat of south-central Idaho, U.S.A. The desert
water harvester utilizes a buried micro-catchment and three buried storage tanks to augment water for wildlife during the
dry season. In this region, mean annual precipitation (MAP) ranges between about 150–250 mm (6″–10″), 70% of which falls during
the cold season, November to May. Mid-summer through early autumn, June through October, is the dry portion of the year. During
this period, the sub-surface water harvester provides supplemental water for wildlife for 30–90 days, depending upon the precipitation
that year. The desert water harvester is constructed with commonly available, “over the counter” materials. The micro-catchment
is made of a square-shaped, 20 mL. “PERMALON” polyethylene pond liner (approximately 22.9 m × 22.9 m = 523 m2) buried at a depth of about 60 cm. A PVC pipe connects the harvester with two storage tanks and a drinking trough. The total
capacity of the water harvester is about 4777 L (1262 U.S. gallons) which includes three underground storage tanks, a trough
and pipes. The drinking trough is refined with an access ramp for birds and small animals. The technology is simple, cheap,
and durable and can be adapted to other uses, e.g. drip irrigation, short-term water for small livestock, poultry farming
etc. The desert water harvester can be used to concentrate and collect water from precipitation and run-off in semi-arid and
arid regions. Water harvested in such a relatively small area will not impact the ground water table but it should help to
grow small areas of crops or vegetables to aid villagers in self-sufficiency. 相似文献
9.
Using of high-resolution topsoil magnetic screening for assessment of dust deposition: comparison of forest and arable soil datasets 总被引:1,自引:0,他引:1
Magnetic susceptibility (κ) is an easily detectable geophysical parameter that can be used as a proxy or semi-quantitative
tracer of atmospheric industrial and urban dusts deposited in topsoil. An enhanced κ value of topsoil is in many cases also
associated with high concentrations of soil pollutants (mostly heavy metals). High-resolution magnetic screening of topsoil
in areas of high pollution influx is a useful tool for detection of pollution “hot spots”. General and regional screening
maps with a grid density of 10 or 5 km have been performed on the basis of forest topsoil measurement only. The purpose of
this study was to perform high-resolution magnetic screening with different grid densities in both forested and agricultural
areas (arable land). Our large study area (ca. 200 km2) was located in a relatively more polluted region of the central part of Upper Silesia, and a second (small) one (ca. 100
m2) was located in the western part of Upper Silesia, with considerably lower influx of pollution. In the framework of this
study, we applied a statistical comparison of data obtained in forested areas and on arable land. The arable soil showed statistically
significantly lower κ values, the result of “physical dilution” of the arable layer caused by annual ploughing. Thus arable
soils must be avoided during high-resolution field measurement. From semivariograms, it was clear that the spatial correlations
in forest topsoil are much stronger than in arable soil, which suggests that a denser measurement grid is required in forested
areas. 相似文献
10.
Anastasios I. Stamou Kimon Hadjibiros Andreas Andreadakis Alexandra Katsiri 《Environmental Modeling and Assessment》2007,12(3):157-170
A water quality model (MERES) is applied in the multi-purpose reservoir of Plastiras in Greece. The model was calibrated with
limited field data using the standard trial and error procedure; next, it was applied for four scenarios of reservoir operation,
which correspond to four values of minimum water levels (MWL). Model results were combined with landscape aesthetics to establish
a “safe” MWL in the reservoir. MWL was proposed to be +784 m, a value that ensures a very good water quality by retaining
the reservoir in the status of “a little beyond oligotrophic” and a very good quality of landscape with an acceptable area
of dead zones; it also ensures an annual release of 127.5 hm3 of water within a reliability level of 90%. This quantity can be considered as acceptable from the water supply point of
view. 相似文献
11.
A framework for dissolved oxygen (DO) modeling of the Ravi River has been developed based on a combination of laboratory measurements
and field and monitoring data. Both the classical Streeter-Phelps (CSP) and the modified Streeter-Phelps (MSP) models are
used for DO simulations. The MSP model considers the carbonaceous biochemical oxygen demand (CBOD) and nitrogenous biochemical
oxygen demand (NBOD) separately, whereas the CSP model is evaluated considering only the CBOD and NBOD is incorporated in
the overall BOD utilization rate. CBOD, NBOD and BOD rates have been determined through long-term BOD analysis of five main
wastewater outfalls and two surface drains discharging into the Ravi River over a 98 km stretch. Analysis by Thomas Method
manifests strong coefficient of determination “R2” between 0.72 and 0.98 for all the three types of BOD rates. Sensitivity analyses have also been carried out to find out
a suitable reaeration rate formula for highly variable flows in the Ravi River. The CSP model results based on classical approach
of considering only CBOD show significant difference between the model predictions and field measurements suggesting that
NBOD needs to be incorporated for the model development. The dissolved oxygen values calculated using the MSP model and the
CSP model based on overall BOD rate are in close agreement with field measurements and are thus suitable to model DO levels
in the Ravi River. 相似文献
12.
Driving Forces for the Marsh Wetland Degradation in the Honghe National Nature Reserve in Sanjiang Plain, Northeast China 总被引:7,自引:0,他引:7
Demin Zhou Huili Gong Yiyong Wang Shahbaz Khan Kuiyi Zhao 《Environmental Modeling and Assessment》2009,14(1):101-111
In the study, we analyze and assess quantitatively the spatial pattern of vegetation and its ecological degradation information
in the Honghe National Nature Reserve (HNNR), a Ramsar-designated site in Northeast China. Statistics from historical survey
data are used to measure the degradation of marshes over time and changes in the hydrological regime. Long-term statistical
data are also employed to analyze both natural and human impacts on these changes. Both the wetland degradation model and
its mechanisms are discussed in this paper. The research finds that the loss of water and other types of degradation in the
vegetation habitat caused by the rapid deterioration of the hydrological regime has threatened the status of HNNR as a “storage
area of natural genes.” Scientifically constructed strategies are urgently required to ensure sustainable economic benefits
that do not adversely affect this nature reserve. 相似文献
13.
M.K.B. Lüdeke O. Moldenhauer G. Petschel-Held 《Environmental Modeling and Assessment》1999,4(4):315-326
Starting from the basic assumption of the syndrome concept that essentially all of the present problematic civilization–nature interactions on the global scale can be subdivided into a limited number of typical patterns, the analysis of the response of these patterns (syndromes) to climate change can make a major contribution to climate impact research, surmounting the difficulties of more common sectoral ceteris paribus impact studies with respect to their systemic integration. In this paper we investigate in particular the influence of climate on the regional proneness or disposition towards one of the most important syndromes with respect to famines and malnutrition, the Sahel Syndrome. It describes the closely interlinked natural and socioeconomic aspects of rural poverty driven degradation of soil and vegetation on marginal sites. Two strategies of global climate impact assessment on a spatial 0.5°×0.5° grid were pursued: (a) As a measure for the climate sensitivity of the regional proneness, the absolute value of the gradient of the disposition with respect to the global field of 3} 12 monthy normals of temperature, irradiation and precipitation is calculated. (b) The disposition was evaluated for two different climate forecasts under doubled atmospheric CO2 concentration. For both strategies two new quantitative global models were incorporated in a fuzzy-logic-based algorithm for determining the disposition towards the Sahel Syndrome: a neural-net-based model for plant productivity and a waterbalance model which calculates surface runoff considering vertical and lateral fluxes, both driven by the set of 36 monthly climatological normals and designed to allow very fast global numerical evaluation.Calculation (b) shows that the change in disposition towards the Sahel Syndrome crucially depends on the chosen climate forecast, indicating that the disagreement of climate forecasts is propagated to the impact assessment of the investigated socio-economic pattern. On the other hand the regions with a significant increase in disposition in at least one of the climate scenario-based model runs form a subset of the regions which are indicated by the local climate sensitivity study (a) as highly sensitive – illustrating that the gradient measure applied here provides a resonable way to calculate an upper limit or worst case of negative climate impact. This method is particularly valuable in the case of uncertain climate predictions as, e.g., for the change in precipitation patterns. 相似文献
14.
Measuring Water Storage Fluctuations in Lake Dongting, China, by Topex/Poseidon Satellite Altimetry 总被引:1,自引:0,他引:1
Zhang J Xu K Yang Y Qi L Hayashi S Watanabe M 《Environmental monitoring and assessment》2006,115(1-3):23-37
Although satellite radar altimetry was developed and optimized for open oceans, it has been used to monitor variations in the level of inland water-bodies such as lakes and rivers. Here, for the first time, we have further used the altimetry-derived variation of water level for estimating the fluctuation of water storage as an addition to the present in situ water storage estimation systems to be used in remote areas and in emergency situation such as in the events flooding monitoring and for studying the effect of climate change. Lake Dongting, the second largest lake in China, influenced frequently by flooding, was, therefore, chosen to demonstrate the potential of the technique. By using the concept of an “assumed reference point”, we converted Topex/Poseidon satellite altimetry data on water level variations in Lake Dongting to “water level” data. The “water level” time-series data and in situ water storage were used to establish a rating curve. From the rating curve, we converted data on “water level” derived from seven years (1993–1999) of Topex/Poseidon data to actual water storage in Lake Dongting. The result reveals that the seasonal and annual fluctuations of water storage occurred during the 1990s with a more frequent flooding at the late 1990s' especially the flooding in whole catchment level in 1998 and 1999. The study supports the usefulness of satellite altimetry for dense and continuous monitoring of the temporal variations in water dynamic in moderate to large lakes. 相似文献
15.
C. Schlumpf J. Behringer G. Dürrenberger C. Pahl-Wostl 《Environmental Modeling and Assessment》1999,4(1):1-12
Participatory Integrated Assessment (PIA) is an approach which aims at developing methods which allow to combine evaluations
of experts and lay people in the field of Integrated Assessment. Thus, policy recommendations derived from PIA exercises are
informed by scientific judgments and by valuations of “non-scientists”. For any PIA methodology the provision of insights,
facts and figures about the policy problem at hand is crucial.
In this paper we describe a PIA methodology which combines the social science research instrument “focus group” with a specific
computer information tool, the “Personal CO2 Calculator” (PCC). The tool supports citizens in discussing and recommending measures on climate change policy. Based on
our experiences, we plead for information instruments that are tuned to and assist concrete target groups with their specific
interests. This helps that policy recommendations derived from PIA exercises are based on both scientific knowledge as well
as citizens' and stakeholders' policy preferences.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
16.
Fawzy MA Badr Nel-S El-Khatib A Abo-El-Kassem A 《Environmental monitoring and assessment》2012,184(3):1753-1771
The concentrations of Cd, Cu, Pb, and Zn in sediments, water, and different plant organs of six aquatic vascular plant species,
Ceratophyllum demersum L. Echinochloa pyramidalis (Lam.) Hitchc. & Chase; Eichhornia crassipes (Mart.) Solms-Laub; Myriophyllum spicatum L.; Phragmites australis (Cav.) Trin. ex Steud; and Typha domingensis (Pers.) Poir. ex Steud, growing naturally in the Nile system (Sohag Governorate), were investigated. The aim was to define
which species and which plant organs exhibit the greatest accumulation and evaluate whether these species could be usefully
employed in biomonitoring and phytoremediation programs. The recorded metals in water samples were above the standard levels
of both US Environmental Protection Agency and Egyptian Environmental Affairs Agency except for Pb. The concentrations of
heavy metals in water, sediments, and plants possess the same trend: Zn > Cu > Pb > Cd which reflects the biomonitoring potentialities
of the investigated plant species. Generally, the variation of heavy element concentrations in water and sediments in relation
to site and season, as assessed by two-way repeated measured ANOVA, was significant (p < 0.05). However, insignificant variations were observed in the concentrations of Pb and Cd in sediments in relation to season
and of Cu and Zn in relation to site. Results also showed that the selectivity of the heavy elements for the investigated
plants varied significantly (p < 0.05) with species variation. The accumulation capability of the investigated species could be arranged according to this
pattern: C. demersum > E. crassipes > M. spicatum > E. pyramidalis > T. domingensis > P. australis. On the basis of the element concentrations, roots of all the studied species contain higher concentrations of Cu and Zn
than shoots while leaves usually acquire the highest concentrations of Pb. Cd concentrations among different plant organs
are comparable except in M. spicatum where the highest Cd concentrations were recorded in the leaves. Our results also demonstrated that all the studied species
can accumulate more than 1,450-fold the concentration of the investigated heavy elements in water rendering them of interest
for use in phytoremediation studies of polluted waters. Given the absence of systematic water quality monitoring, heavy elements
in plants, rather than sediments, provide a cost-effective means for assessing heavy element accumulation in aquatic systems
during plant organ lifespan. 相似文献
17.
Impact of Coal Power Plant Emission on the Foliar Elemental Concentrations in Plants in a Low Rainfall Tropical Region 总被引:1,自引:0,他引:1
A field study was conducted around two thermal power plants of India to quantify the changes in foliar elemental concentrations due to emission in a low rainfall tropical area. Sulphur dioxide and particulates were at high levels which may cause serious ecological effects. Emission from the power plants has altered the elemental concentrations in the leaves of evergreen and deciduous plants. The foliar total-S and SO4
2–-S levels were significantly higher in all the plants growing at polluted sites. However, the organic-S content was more or less unaltered. In evergreen plants, the SO4
2–-S content increased gradually from summer through winter, whereas in the deciduous plants there was a higher magnitude of increase after onset of new leaves during summer. With the increasing pollution load, foliar Ca2+ and K+ contents increased, whereas N content decreased. The reduction in N content was greater during summer in evergreen plants and during winter in deciduous plants. The plants growing closer to the power plants accumulated more trace elements (Mn, Fe, Cd, Pb and Ni) as compared to those growing at distant sites. In deciduous plants the leaf fall during winter lowered down the trace element 相似文献
18.
Diamond J Stribling JB Stribling JR Huff L Gilliam J 《Environmental monitoring and assessment》2012,184(4):2247-2260
Many organizations in the USA collect aquatic bioassessment data using different sampling and analysis methods, most of which
have unknown performance in terms of data quality produced. Thus, the comparability of bioassessments produced by different
organizations is often unknown, ultimately affecting our ability to make comprehensive assessments on large spatial scales.
We evaluated a pilot approach for determining bioassessment performance using macroinvertebrate data obtained from several
states in the Southeastern USA. Performance measures evaluated included precision, sensitivity, and responsiveness to a human
disturbance gradient, defined in terms of a land disturbance index value for each site, combined with a value for specific
conductance, and instream habitat quality. A key finding of this study is the need to harmonize ecoregional reference conditions
among states so as to yield more comparable and consistent bioassessment results. Our approach was also capable of identifying
potential areas for refinement such as reevaluation of less precise, sensitive, or responsive metrics that may result in suboptimal
index performance. Higher performing bioassessments can yield information beyond “impaired” versus “unimpaired” condition.
Acknowledging the limitations of this pilot study, we would recommend that performance evaluations use at least 50 sites,
10 of which are ecoregional reference sites. Efforts should be made to obtain data from the entire human disturbance gradient
in an ecoregion to improve statistical confidence in performance measures. Having too few sites will result in an under-representation
of certain parts of the disturbance gradient (e.g., too few poor quality sites), which may bias sensitivity and responsiveness
estimates. 相似文献
19.
Integrated Environmental Assessment (IEA) can be loosely defined as policy‐relevant, multidisciplinary research on environmental
issues. Many, diverse activities in this broad field are ongoing, but the approaches lack the structure, standardization and
quality control common in disciplinary research. IEA has three stages: “structuring the problem”, “analyzing the problem”
and “communicating the findings and insights”. Each stage has its inherent difficulties, not least because problem definition
and analysis are neither separable nor unambiguous nor unique. Difficulties are exacerbated in the first and third stages
by the necessity for science and policy to work together. Difficulties are exacerbated in the second stage by the necessity
of different scientific disciplines to cooperate. The European Forum on Integrated Environmental Assessment is an initiative
to improve scientific quality and policy‐relevance of IEA, by organizing two series of workshops, one looking in detail at
current and desired scientific practices, the other reviewing current and establishing further applications of IEA to environmental
issues in Europe.
This revised version was published online in July 2006 with corrections to the Cover Date.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
20.
Combining policy instruments for sustainable energy systems: An assessment with the GMM model 总被引:1,自引:0,他引:1
Peter Rafaj Leonardo Barreto Socrates Kypreos 《Environmental Modeling and Assessment》2006,11(4):277-295
An assessment of the impact of an illustrative portfolio of policy instruments that address different sustainability concerns in the global energy system in areas of climate change, air pollution and introduction of renewable-energy resources is conducted. The effects of a policy set containing three instruments, implemented either individually or in combination, were examined. The policy instruments under examination in this work include: Cap-and-Trade policies imposing a CO2 emission reduction target on the global energy system, a renewable portfolio standard that forces a minimum share of renewable electricity generation, and the internalisation of external costs of power generation associated with local pollution. Implementation of these policy instruments significantly changes the structure and environmental performance of the energy sector, and particularly the structure of the electric-generation sector. The positive effects are amplified when the policy instruments are simultaneously applied, illustrating the potential for synergies between these energy-policy domains. The analysis has been conducted with the multi-regional, energy-system Global MARKAL Model (GMM), a “bottom-up” partial-equilibrium model that provides a detailed representation of energy technologies and endogenizes technology learning.
★A preliminary version of this paper has been presented at the 6th IAEE European Energy Conference on “Modelling in Energy Economics and Policy”, 1–3 September 2004, ETH Zürich, Switzerland. 相似文献