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1.
Damage functions from a range of sources are used to estimate deterioration of carbonate stone, iron and copper, in addition to the rate of blackening of stone surfaces in London across the period 1100-2100 CE. Meteorological and pollution input is available for only a relatively short part of this span, so non-instrumental weather records and modelled pollution are utilised for historic values, while future climate is adapted from the HadCM3A2 model output and pollution assessed from likely regulatory trends. The results from the different damage functions compare reasonably well showing comparable changes in damage rates with time. A potential square-root dependence of change in deposition velocity of SO2 to limestone suggests a possible overestimate of damage when pollution is high. Deterioration is especially intense from the 1700s. It is difficult to be certain whether the corrosion of copper accelerated as early as this or it developed in the 20th century. Nevertheless all the functions predict a decline in copper corrosion from the end of the 20th century. A blackening function was developed to relate elemental carbon concentration and the colour of deposited particulate matter to blackening rate, which suggests that soiling was particularly rapid in the late 19th century. The increase and subsequent decrease in damage to building materials is interpreted in terms of a Kuznets curve. The centuries where pollution controlled damage to durable building material seems to be over. Weathering, in a changing climate may have the greatest impact in the future.  相似文献   

2.
Surfaces of freshly cut Bath limestone exposed along various roadsides before and after the reduction of traffic in the historical city centre of Oxford, England (following the Oxford Transport Strategy or OTS), presented an opportunity to investigate changes in soiling and fungal growth in relation to changing traffic pollution. Spectrophotometric data using an X-Rite SP68 sphere spectrophotometer provided quantitative information on soiling before and after the OTS. Scanning electron microscopy (SEM) provided a means to view and quantify the microbial inhabitants in detail, using a technique which registered and counted branching beaded structures. Results indicated that at Longwall Street soiling became more pronounced and microbial cover lower, with the reverse occurring at High Street where the greatest improvements in surface lightness were found. Other sites showed less clearcut responses in soiling and microbial growth. Overall, microbial growth was pronounced within hollows on stone surfaces before the OTS, with some signs of spreading of growths away from hollows after the OTS. A complex relationship between air pollution, soiling, and microfloral growths is revealed by the study which needs to be taken into account in soiling management strategies.  相似文献   

3.
Several exposure campaigns of silica-soda-lime window glass have been performed in 30 European sites and 1 in Canada in order to understand, quantify and model the phenomenon of soiling. In this purpose samples were exposed sheltered from the rain. Parallel to exposure, several meteorological parameters and pollution concentrations have been monitored. This paper shows first results on the establishment of a dose-response function for glass soiling. Statistical analyses show that PM10 is not the only parameter, but also SO2 and NO2 atmospheric concentrations seem to be responsible for the optical impairment of glass surfaces, expressed as haze.  相似文献   

4.
5.
The impact of climate change on monuments and historic buildings is addressed for the first time, in terms of modelling and predicting thermal stress on stone in Europe over the next century. While the effect of changing climate on frost in porous materials and on surface recession of carbonate stone, has recently been treated, prediction of the future evolution of thermal stress on stones still requires elucidation. The present paper provides maps showing future scenarios of thermal stress on Carrara marble for the 21st century, using the output data from the Hadley general and regional climate models in the European window.The work carried out made it possible to forecast in the near and far futures (i.e. 2010-2039, 2070-2099) the number of events per year of thermal stress in marble greater than 20 MPa, the latter being adopted as the maximum sustainable load for this specific material. The data demonstrate that the Mediterranean area will continue to experience the highest level of risk from thermal stress, with more than 300 events/year predicted in the 2070-2099 period. In addition, Central Europe will be more affected by thermal stress during the present century compared to the baseline period, 1961-1990, taken as reference.  相似文献   

6.
Climate change and forest fires   总被引:6,自引:0,他引:6  
This paper addresses the impacts of climate change on forest fires and describes how this, in turn, will impact on the forests of the United States. In addition to reviewing existing studies on climate change and forest fires we have used two transient general circulation models (GCMs), namely the Hadley Centre and the Canadian GCMs, to estimate fire season severity in the middle of the next century. Ratios of 2 x CO2 seasonal severity rating (SSR) over present day SSR were calculated for the means and maximums for North America. The results suggest that the SSR will increase by 10-50% over most of North America; although, there are regions of little change or where the SSR may decrease by the middle of the next century. Increased SSRs should translate into increased forest fire activity. Thus, forest fires could be viewed as an agent of change for US forests as the fire regime will respond rapidly to climate warming. This change in the fire regime has the potential to overshadow the direct effects of climate change on species distribution and migration.  相似文献   

7.
A set of materials (Portland limestone, white painted steel, white plastic and polycarbonate filter material) was exposed at locations in London, Athens and Krakow. Regular measurements of reflectance were taken over a period of twelve months. Co-located measurements of PM10 concentrations were available. Based on these results, the relationship between soiling (measured as loss of reflectance) and ambient PM10 concentrations was quantified leading to the development of dose–response functions for the soiling of materials. The results for limestone revealed too much scatter for a prediction to be made. Implications for air quality management and for the conservation of cultural heritage buildings are considered, including public acceptability and economic factors.  相似文献   

8.
To explore the evolution of a human impacted river, the Seine (France), over the 21st century, three driving factors were examined: climate, agriculture, and point source inputs of domestic and industrial origin. Three future scenarios were constructed, by modification of a baseline representative of recent conditions. A climate change scenario, based on simulations by a general circulation model driven by the SRES-A2 scenario of radiative forcing, accounts for an average warming of +3.3 degrees C over the watershed and marked winter increase and summer decrease in precipitation. To illustrate a possible reduction in nitrate pollution from agricultural origin, a scenario of good agricultural practices was considered, introducing catch crops and a 20% decrease in nitrogen fertilisation. Future point source pollution was estimated following the assumptions embedded in scenario SRES-A2 regarding demographic, economic and technologic changes, leading to reductions of 30 to 75% compared to 2000, depending on the pollutants. Four models, addressing separate components of the river system (agronomical model, hydrogeological model, land surface model and water quality model), were used to analyse the relative impact of these scenarios on water quality, in light of their impact on hydrology and crop production. The first-order driving factor of water quality over the 21st century is the projected reduction of point source pollution, inducing a noticeable decrease in eutrophication and oxygen deficits downstream from Paris. The impact of climate change on these terms is driven by the warming of the water column. It enhances algal growth in spring and the loss factors responsible for phytoplankton mortality in late summer (grazers and viruses). In contrast, increased seasonal contrasts in river discharge have a negligible impact on river water quality, as do the changes in riverine nitrate concentration, which never gets limiting. The latter changes have a similar magnitude under the three scenarios. Under climate change, riverine and groundwater nitrate concentrations increase and crop production is advantaged with reduced growing cycles and increased yields. In contrast, nitrate concentrations decrease under the good agricultural practices scenario, with a limited decrease in crop production. When these two scenarios are combined, the changes in nitrate concentrations balance each other and crop yields increase. The results of this numerical exercise indicate that the potential changes to the Seine River system during the 21st century will not lead to severely degraded water quality.  相似文献   

9.
Impacts of land-use on estuarine environmental parameters and nutrients are well documented, but little is known about these characteristics during extensive periods of low water flow (i.e., drought). Droughts are set to increase in frequency and magnitude with climate change, and understanding their influence on ecosystems is imperative. We investigated differences in environmental parameters and nutrients in urban and rural estuaries during a period of prolonged low flow. Sampling was done along each estuary at multiple times to place small-scale variability in the context of land-use differences. No differences were detected between land-use for environmental parameters or nutrients in mean effects or variance structure. Urban estuaries had reduced variation in nutrients over time compared to rural estuaries, which suggested that their concentrations are more stable. Large differences existed within and between individual estuaries, and over time. Low freshwater flow conditions in estuaries provide a glimpse to future climate change impacts of drought, and a baseline upon which pollution and anthropogenic effects can be assessed.  相似文献   

10.
Recent research in catchments of rapidly developing countries such as Brazil and China suggests that many catchments of the developing world are already showing signs of nitrogen pollution reminiscent of past experiences in developed countries. This paper looks at both the individual and combined effects of future climate change and other likely environmental changes on in-stream nitrate concentrations in a catchment in Northern Turkey. A model chain comprised of simulated future temperature and precipitation from a Regional Circulation Model (RCM), a conceptual hydrological model (HBV) and a widely tested integrated catchment nitrogen model (INCA-N) is used to model future changes in nitrate concentrations. Two future periods (2021-2050 and 2069-2098) are compared to the 1961-1990 baseline period in order to assess the effectiveness of several possible interventions available to catchment authorities. The simulations show that in the urbanised part of the catchment, the effects of climate change and other environmental changes act in the same direction, leading to peak nitrate concentrations of 7.5 mg N/l for the 2069-2098 period, which corresponds to a doubling of the baseline values. Testing different available policy options reveals that the installation of wastewater treatment works (WWTWs) in all major settlements of the catchment could ensure nitrate levels are kept at near their baseline values for the 2021-2050 period. Nevertheless, a combination of measures including WWTWs, meadow creation, international agreements to reduce atmospheric N concentrations and controls on agricultural practises will be required for 2069-2098. The approach presented in this article could be employed in order to anticipate future pollution problems and to test appropriate solutions, some of which will necessitate international co-operation, in other catchments around the world.  相似文献   

11.
Andy Baker 《Water research》2002,36(1):189-195
Some farm wastes have been analysed for their fluorescence properties using fluorescence excitation-matrix (EEM) spectroscopy. Farm wastes investigated were silage liquor, pig and cattle slurry, and sheep barn waste. All farm wastes exhibited high intensities of fluorescence that can be attributed to the protein tryptophan. Silage liquor was characterised by a very high fluorescence intensity and an initial tryptophan: fulvic-like fluorescence intensity ratio of >20. Cattle and pig slurries exhibited a lower tryptophan : fulvic-like fluorescence intensity ratio (approximately 2-5) and lower tryptophan fluorescence intensity, and tyrosine fluorescence was also observed. Sheep barn wastes had the lowest tryptophan: fulvic-like fluorescence intensity ratios (approximately 0.5-4.0). Farm waste samples were reanalysed under controlled temperature conditions over a period of 50 days after sampling, to investigate the stability of their fluorescence properties. For silage liquor. tryptophan: fulvic-like fluorescence intensity ratios were observed to decrease with time, and were associated with a decrease in tryptophan fluorescence intensity, suggestive of clostridia breakdown of protein. For slurry samples. tryptophan: fulvic-like fluorescence intensity exhibited a more variable time-evolution, and tryptophan fluorescence intensity increased through time; the more complex fluorescence signal is due to the relatively heterogeneous nature of the slurry. Sheep barn waste samples exhibited more stable tryptophan: fulvic-like fluorescence intensity ratio and tryptophan intensities, suggesting these samples were more stable due to their greater age and decomposition. The ratios of tryptophan: fulvic-like fluorescence intensity observed from the farm wastes investigated are significantly higher than those observed in the majority of river waters, suggesting that farm waste pollution events could leave a signature in river waters due to their distinctively high protein fluorescence intensity.  相似文献   

12.
Capsella bursa-pastoris (L.) Medic. (shepherd's purse) has been tested as a possible biomonitor of heavy metals in the city of Bradford, UK and compared with Poa annua L. (annual meadow-grass), a species with a similar ecology that had previously been studied for biomonitoring potential. Forty-two sites (urban roadside, urban, urban park, suburban and rural) in and around Bradford were investigated. Concentrations of Pb, Cd, Zn and Cu have been determined in soils and in washed and unwashed plant leaves. Differences between the washed and unwashed samples, reflecting airborne and soil entry routes, respectively, varied according to the metal pollutant. There were significant relationships between the heavy metal concentration in samples of surface soil (depth 0-10 cm) and washed leaves, the concentrations being greater with progressively increased urbanisation of the sites. Capsella bursa-pastoris has been found to be a useful biomonitor of the four heavy metals studied, and it may be a particularly useful species since it could monitor short-term changes in pollution in urban areas.  相似文献   

13.
Land use regression (LUR) has emerged as an effective and economical means of estimating air pollution exposures for epidemiological studies. To date, no systematic method has been developed for optimizing the variable selection process. Traditionally, a limited number of buffer distances assumed having the highest correlations with measured pollutant concentrations are used in the manual stepwise selection process or a model transferred from another urban area.In this paper we propose a novel and systematic way of modeling long-term average air pollutant concentrations through “A Distance Decay REgression Selection Strategy” (ADDRESS). The selection process includes multiple steps and, at each step, a full spectrum of correlation coefficients and buffer distance decay curves are used to select a spatial covariate of the highest correlation (compared to other variables) at its optimized buffer distance. At the first step, the series of distance decay curves is constructed using the measured concentrations against the chosen spatial covariates. A variable with the highest correlation to pollutant levels at its optimized buffer distance is chosen as the first predictor of the LUR model from all the distance decay curves. Starting from the second step, the prediction residuals are used to construct new series of distance decay curves and the variable of the highest correlation at its optimized buffer distance is chosen to be added to the model. This process continues until a variable being added does not contribute significantly (p > 0.10) to the model performance. The distance decay curve yields a visualization of change and trend of correlation between the spatial covariates and air pollution concentrations or their prediction residuals, providing a transparent and efficient means of selecting optimized buffer distances. Empirical comparisons suggested that the ADDRESS method produced better results than a manual stepwise selection process of limited buffer distances. The method also enables researchers to understand the likely scale of variables that influence pollution levels, which has potentially important ramifications for planning and epidemiological studies.  相似文献   

14.
Over the past 15 years, much scientific work has been published on the potential human impacts on climates. For their Third Assessment Report in 2001, the United Nations International Programme on Climate Change developed a set of economic development scenarios, which were then run with the four major general circulation models (GCM) to estimate the anthropogenesis-forced climate change. These GCMs produce worldwide grids of predicted monthly temperature, cloud, and precipitation deviations from the period 1961–1990. As this period is the same used for several major typical meteorological year data sets, these typical data sets can be used as a starting point for modifying weather files to represent predicted climate change. Over the past 50 years, studies of urban heat islands (UHI) or urbanization have provided detailed measurements of the diurnal and seasonal patterns and differences between urban and rural climatic conditions. While heat islands have been shown to be a function of both population and microclimatic and site conditions, they can be generalized into a predictable diurnal and seasonal pattern. Although the scientific literature is full of studies looking at the impact of climate change driven by human activity, there is very little research on the impact of climate change or urban heat islands on building operation and performance across the world. This article presents the methodology used to create weather files which represent climate change scenarios in 2100 and heat island impacts today. For this study, typical and extreme meteorological weather data were created for 25 locations (20 climate regions) to represent a range of predicted climate change and heat island scenarios for building simulation. Then prototypical small office buildings were created to represent typical, good, and low-energy practices around the world. The simulation results for these prototype buildings provide a snapshot view of the potential impacts of the set of climate scenarios on building performance. This includes location-specific building response, such as fuel swapping as heating and cooling ratios change, impacts on environmental emissions, impacts on equipment use and longevity comfort issues, and how low-energy building design incorporating renewables can significantly mitigate any potential climate variation. In this article, examples of how heat island and climate change scenarios affect diurnal patterns are presented as well as the annual energy performance impacts for three of the 25 locations. In cold climates, the net change to annual energy use due to climate change will be positive – reducing energy use on the order of 10% or more. For tropical climates, buildings will see an increase in overall energy use due to climate change, with some months increasing by more than 20% from current conditions. Temperate, mid-latitude climates will see the largest change but it will be a swapping from heating to cooling, including a significant reduction of 25% or more in heating energy and up to 15% increase in cooling energy. Buildings which are built to current standards such as ASHRAE/IESNA Standard 90.1-2004 will still see significant increases in energy demand over the twenty-first century. Low-energy buildings designed to minimize energy use will be the least affected, with impacts in the range of 5–10%. Unless the way buildings are designed, built, and operated changes significantly over the next decades, buildings will see substantial operating cost increases and possible disruptions in an already strained energy supply system.  相似文献   

15.
Ice storms and forest impacts   总被引:1,自引:0,他引:1  
Ice storms, or icing events, are important meteorological disturbances affecting forests over a surprisingly large portion of the USA. A broad belt extending from east Texas to New England experiences major ice storms at least once a decade; and truly major events occur in the heart of this belt once or twice a century. In the areas most affected, icing events are a factor that shapes stand composition, structure, and condition over wide areas. Impacts of individual storms are highly patchy and variable, and depend on the nature of the storm. Impacts also depend on how (or if) forest managers conduct subsequent salvage cuttings. Important research needs remain to be considered by the forest ecology and meteorology communities. At present, how ice storm frequency and severity may change with future climate change is unknown.  相似文献   

16.
River floodplains are dynamic and fertile ecosystems where soil invertebrates such as earthworms can reach high population densities. Earthworms are an important food source for a wide range of organisms including species under conservation such as badgers. Flooding, however, reduces earthworm numbers. Populations recover from cocoons that survive floods. If the period between two floods is too short such that cocoons cannot develop into reproductive adults, populations cannot sustain themselves. Both climate change and floodplain rehabilitation change the flooding frequency affecting earthworm populations. The present paper estimates the influence of climate change and floodplain rehabilitation on the viability of earthworm populations in a Dutch floodplain; the Afferdensche and Deestsche Waarden along the River Waal. This floodplain will be part of major river rehabilitation plans of the Dutch government. In those plans, the floodplain will experience the construction of a secondary channel and the removal of part of its minor embankment. To estimate the impact of these plans and climate change, we used a dataset of daily discharges for 1900-2003 for the River Rhine at the Dutch-German border. We perturbed this dataset to obtain two new datasets under climate change scenarios for 2050 and 2100. From the original and two projected datasets we derived the frequency distributions for the annual periods without inundations for the studied floodplain. We subsequently compared the duration of these inundation-free (dry) periods with the maturation age distribution for L. rubellus as derived from a Dynamic Energy Budget model. This comparison yielded in which parts of our study area and under which climate conditions the populations would still be viable, be able to adapt or become extinct. The results show that climate change has almost no adverse effect on earthworm viability. This is because climate change reduces the flooding frequency during the earthworms growing season. Floodplain rehabilitation, on the other hand, reduces the part of the floodplain area where populations can sustain themselves. Before rehabilitation, only 12% of the floodplain area cannot sustain a viable earthworm population. After rehabilitation, this increases to 59%, 28% of which is due to more frequent flooding. Enhanced exposure to soil contaminants may further suppress earthworm viability. This could frustrate further nature development and the viability of earthworm-dependent species such as the badger (Meles meles) or little owl (Athene noctua vidalli species), which is an objective of the river rehabilitation plans in the Netherlands.  相似文献   

17.
Samples of naturally growing moss (mainly Pseudoscleropodium purum and Hypnum cupressiforme ) were used to investigate the distribution of photon-emitting radionuclides, notably 129I , 137Cs, 144Ce and 241Am, at distances up to 12 km from the nuclear fuel reprocessing plant at Sellafield in West Cumbria . The relative activities of the naturally occurring radionuclides, 7Be and 210Pb, in moss and air indicated that the removal half-time of these radionuclides on moss is very long (best estimate of half-time, corrected for radioactive decay, was 240 days) and that the mosses are very efficient collectors of airborne particulates (product of deposition velocity and interception factor was 2.4 X 10(-2) ms-1). Hence the activities of artificially-produced radionuclides on the mosses present an effective record of local airborne radionuclide pollution integrated over a number of years. The activity of 210Pb in each sample was used to standardize the activities of artificial radionuclides in the samples. It was found that the activity ratio of 129I /210Pb, 137Cs/210Pb and 144Ce/210Pb declined with distance from Sellafield indicating that the major local source of these radionuclides has been material discharged to air from the site. The activity ratio of 241Am/210Pb declined with distance from the site and also with distance from the sea confirming that the resuspension of material originally discharged to sea is an important local source of 241Am.  相似文献   

18.
Over the last two decades significant effort has been dedicated to understanding the fate and transport of pesticides in surface water and groundwater and to use this understanding in the development of environmental policy and regulation. However, there have been few studies that have investigated the relationships between pesticides and climate change, and where this work has been undertaken it has principally been in relation to the impacts of climate change on agricultural production rather than in the context of environmental protection. This study addresses that gap by reviewing how climate change may impact the fate and transport of pesticides in surface and groundwaters as a pre-cursor to quantitative studies. In order to structure the review, we have adopted a source-pathway-receptor approach where climate sensitivities of pesticide source terms, environmental pathways and receptors are reviewed. The main climate drivers for changing pesticide fate and behaviour are thought to be changes in rainfall seasonality and intensity and increased temperatures, but the effect of climate change on pesticide fate and transport is likely to be very variable and difficult to predict. In the long-term, indirect impacts, such as land-use change driven by changes in climate, may have a more significant effect on pesticides in surface and groundwaters than the direct impacts of climate change on pesticide fate and transport. The review focuses on climate change scenarios and case studies from the UK; however, the general conclusions can be applied more widely.  相似文献   

19.
There is considerable debate regarding the potential role of Carbon Capture and Storage (CCS) technologies in reducing Australia's greenhouse emissions. The latest climate change science suggests that major (60% or more by 2050), rapid (peaking within 20 years) cuts in global emissions may be required to avoid dangerous climate change. There are a number of existing abatement options including energy efficiency, various renewable energy technologies, nuclear power and fuel switching to natural gas; as well as emerging options including CCS. We outline a simple technology assessment framework for policymakers to evaluate these different options given the climate change imperative. This framework includes technology status, delivered energy services, present and possible future costs, potential scale of abatement, potential speed of deployment and other possible social outcomes. Application of this framework to CCS suggests that it should be considered as a promising, but still somewhat unproven, option that potentially offers very significant abatement potential and good integration into the existing energy industry. There are, however, some outstanding questions regarding its effectiveness and safety, its abatement is likely to come at significant cost, and it is unlikely to be able to make a significant contribution for well over a decade. The Australian policy implications are that while government support for R&D and Demonstration of CCS is appropriate and should in our view be expanded, the major priority should be to support greater deployment of existing abatement options including energy efficiency, efficient gas-fired generation and cogeneration and renewable energy. Such policy support is noticeably lacking at present.  相似文献   

20.
Plastic surfaces are used widely as flooring materials in public and residential buildings. When new floor coverings are developed, both field and laboratory tests are needed. In this study the tendency to soiling and wearing and the cleanability of six commercial plastic flooring surfaces were examined in both field and laboratory conditions. The plastic flooring surfaces were studied using colorimetry and scanning electron microscopy (SEM). In the field experiments, outdoor conditions greatly affected soiling of the floorings, whereas the number of persons walking over the flooring did not correlate with the soiling values in the two buildings examined. Laboratory tests provided results rapidly and the plastic materials were ranked in a similar order of superiority both in the field and laboratory experiments. Furthermore, there was a significant correlation between the cleanability of the surfaces in the field and laboratory experiments (r = 0.94). The laboratory methods can therefore be used for obtaining indicative information for selecting materials for practical use and for comparing the cleanability properties of the materials.  相似文献   

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