Greenhouse gas emissions from agriculture, land use, land use change and forestry (ALULUCF) are a significant percentage of UK industrial emissions. The UK Government is committed to ambitious targets for reducing emissions and all significant industrial sources are coming under increasing scrutiny. The task of allocating shares of future reductions falls to the newly appointed Committee on Climate Change (CCC), which needs to consider efficient mitigation potential across a range of sectors. Marginal abatement cost curves are derived for a range of mitigation measures in the agriculture and forestry sectors over a range of adoption scenarios and for the years 2012, 2017 and 2022. The results indicate that in 2022 around 6.36 MtCO2e could be abated at negative or zero cost. Further, in same year over 17% of agricultural GHG emissions (7.85MtCO2e) could be abated at a cost of less than the 2022 Shadow Price of Carbon (£34tCO2e).
If climate change mitigation is a right of humanity and planet Earth, “Global Risk”, as an index – the combined world political, economic, social and warfare risk that is rapidly resulting from the unparalleled planetary ecological degradation with strategic natural-resource scarcity, over pollution and contamination, drastic climate change, ozone layer depletion, excessive biodiversity loss, as well as nuclear weapons and waste build-up – needs to be thinned down as a political and economic priority of the world to mitigate both climate change and economic recession.
It proposes a politically viable and integrative policy framework for a new climate treaty beyond Kyoto to unite all nations in a financially feasible way to achieve global scale climate change mitigation; that is, a fundamental shift in policy and tools, of moving out of a cost approach towards a profit-seeking one for the gradual build-up of the “Green Capitalist Economy”, through vital enhancements of the Kyoto Protocol, including capital market instruments such as the “Ecological” stock in the climate change mitigation process within the short term, so that there will be no reason to wait until after 2012 to start profiting within the climate change mitigation process.
Many decisions concerning long-lived investments already need to take into account climate change. But doing so is not easy for at least two reasons. First, due to the rate of climate change, new infrastructure will have to be able to cope with a large range of changing climate conditions, which will make design more difficult and construction more expensive. Second, uncertainty in future climate makes it impossible to directly use the output of a single climate model as an input for infrastructure design, and there are good reasons to think that the needed climate information will not be available soon. Instead of optimizing based on the climate conditions projected by models, therefore, future infrastructure should be made more robust to possible changes in climate conditions. This aim implies that users of climate information must also change their practices and decision-making frameworks, for instance by adapting the uncertainty-management methods they currently apply to exchange rates or R&D outcomes. Five methods are examined: (i) selecting “no-regret” strategies that yield benefits even in absence of climate change; (ii) favouring reversible and flexible options; (iii) buying “safety margins” in new investments; (iv) promoting soft adaptation strategies, including long-term prospective; and (v) reducing decision time horizons. Moreover, it is essential to consider both negative and positive side-effects and externalities of adaptation measures. Adaptation–mitigation interactions also call for integrated design and assessment of adaptation and mitigation policies, which are often developed by distinct communities.
Organic agriculture as an adaptation strategy to climate change and variability is a concrete and promising option for adaptation in rural communities. Organic agriculture has additional potential as a mitigation strategy. This text is a short review article on this topic. Adaptation and mitigation based on organic agriculture can build on well-established practice, as organic agriculture is a sustainable livelihood strategy with decades of experience in several climate zones and under a wide range of specific local conditions. The financial requirements of organic agriculture as an adaptation or mitigation strategy are low. Further research is needed on yields in organic agriculture and its mitigation and sequestration potential. Other key critical points are information provision and institutional structures such as market access.
The Intergovernmental Panel on Climate Change Fourth Assessment Report (IPCC 2007) declared that few studies have been conducted
on the possible impact of climate change in Southeast Asia despite the fact that commercial and subsistence marine and freshwater
fisheries and aquaculture are important for the food security and the economies of many countries in the region. In the Philippines
alone, fisheries account for 4% of the gross national product (GNP). The fisheries sector employs approximately a million
people, about 26% of whom are engaged in aquaculture operations, 6% in commercial fishing, and 68% in marine and freshwater
municipal fishing (i.e., artisanal, small-scale, or traditional fisheries). The Intergovernmental Panel on Climate Change
(IPCC) concluded that: (1) in the low latitudes of the tropics, many wet areas will get wetter and many dry areas will get
drier, aggravating drought and flood tendencies; (2) weather events will become more extreme, creating more variability in
water supplies that drive agricultural and hydrological systems; (3) rising water temperatures may reduce the upwelling of
food supplies that fish in the upper layers depend on, and increased carbon dioxide in the atmosphere will increase the acidity
of water bodies, adversely affecting shellfish and coral reefs; and (4) coastal areas and islands will be particularly hard-hit
by the combination of rising sea levels and more intensive oceanic storms such as typhoons and hurricanes (IPCC 2007).
International emissions trading is widely seen as an indispensable policy pillar of climate change mitigation [Stern, N., 2007. The Economics of Climate Change. The Stern Review. Cambridge University Press, New York]. This article analyzes five different types of trading architectures, classified into two top-down (UNFCCC driven) and three bottom-up (driven by individual countries or regions) approaches. The two types of approaches are characterized by a trade-off between environmental effectiveness and political feasibility, respectively, whereas their relative cost-effectiveness depends on implementation details. Bottom-up architectures constitute imperfect substitutes for top-down architectures in terms of environmental effectiveness, and thus remain mere fallback options. However, especially the 'formal linking' architecture can act as complement in terms of cost-effectiveness.
This paper presents a methodological roadmap to assess macro-economic damages from climate change. To do so, it explores a
single manifestation of climate change in a single location: an increase in hurricane intensity in the United States. The
presentation starts from a global climate change, namely a homogenous 10 percent increase in hurricane potential intensity,
and follows the causal chain to total macro-economic losses. First, the large-scale change is downscaled to a spatial scale
pertinent to investigate socio-economic impacts. Here, the Emanuel hurricane model is used to estimate present and future
local landfall probabilities. Second, a statistical analysis of historical landfalls is used to translate these probability
changes into direct economic losses. The paper also discusses several adaptation strategies that could be implemented to limit
these losses. Finally, a modified Input-Output model is used to investigate indirect losses due to macroeconomic mechanisms
and feedbacks. This model translates the changes in direct losses into changes in total losses. The model suggests that total
losses increase non-linearly, amplifying the role of the most extreme events. The paper then proposes adaptation strategies
that can reduce indirect losses by improving the ability of the economy to reconstruct and deal with the consequences of disaster.
This study illustrates a methodology to assess economic impacts of climate change at city scale, focusing on sea level rise and storm surge. It is based on a statistical analysis of past storm surges in the studied city, matched to a geographical-information analysis of the population and asset exposure in the city, for various sea levels and storm surge characteristics. An assessment of direct losses in case of storm surge (i.e. of the damages to buildings and building content) can then be computed and the corresponding indirect losses – in the form of production and job losses, reconstruction duration, amongst other loses – deduced, allowing a risk analysis of the effectiveness of coastal flood protections, including risk changes due to climate change and sea level rise. This methodology is applied in the city of Copenhagen, capital of Denmark, which is potentially vulnerable to the effects of variability in sea level, as a low lying city....
Food production in China is a fundamental component of the national economy and driver of agricultural policy. Sustaining and increasing output to meet growing demand faces significant challenges including climate change, increasing population, agricultural land loss and competing demands for water. Recent warming in China is projected to accelerate by climate models with associated changes in precipitation and frequency of extreme events. How changes in cereal production and water availability due to climate change will interact with other socio-economic pressures is poorly understood. By linking crop and water simulation models and two scenarios of climate (derived from the Regional Climate Model PRECIS) and socio-economic change (downscaled from IPCC SRES A2 and B2) we demonstrate that by the 2040s the absolute effects of climate change are relatively modest. The interactive effects of other drivers are negative, leading to decreases in total production of −18% (A2) and −9% (B2). Outcomes are highly dependent on climate scenario, socio-economic development pathway and the effects of CO2 fertilization on crop yields which may almost totally offset the decreases in production. We find that water availability plays a significant limiting role on future cereal production, due to the combined effects of higher crop water requirements (due to climate change) and increasing demand for non-agricultural use of water (due to socio-economic development). Without adaptation, per capita cereal production falls in all cases, by up to 40% of the current baseline.
This work models the carbon neutralization capacity of Brazil's ethanol program since 1975. In addition to biofuel, we also assessed the mitigation potential of other energy products, such as, bioelectricity, and CO2 emissions captured during fermentation of sugar cane's juice. Finally, we projected the neutralization capacity of sugar cane's bio-energy system over the next 32 years. The balance between several carbon stocks and flows was considered in the model, including the effects of land-use change. Our results show that the neutralization of the carbon released due to land-use change was attained only in 1992, and the maximum mitigation potential of the sugar cane sector was 128 tonnes of CO2 per ha in 2006. An ideal reconstitution of the deployment of the sugar cane sector, including the full exploitation of bio-electricity's potential, plus the capture of CO2 released during fermentation, shows that the neutralization of land-use change emissions would have been achieved in 1988, and its mitigation potential would have been 390 tCO2/ha. Finally, forecasts of the sector up to 2039 shows that the mitigation potential in 2039 corresponds to 836 tCO2/ha, which corresponds to 5.51 kg of CO2 per liter of ethanol produced, or 55% above the negative emission level.
Under the Kyoto Protocol, the Clean Development Mechanism (CDM) is designed to serve the dual purposes of allowing the industrialised countries to earn credits by investing in project activities that reduce greenhouse gas (GHG) emissions, while contributing to sustainable development in developing countries via the flows of technology and capital. The fact that the geographic distribution of CDM projects is highly uneven motivates this research into whether certain geographic endowments matter for the CDM development. This research suggests that CDM credit flows in a country is positively affected by those in its neighbouring countries. Countries with higher absolute latitudes and elevations tend to initiate more CDM projects, whereas countries having richer natural resources do not seem to undertake more CDM projects. This finding sheds light on the geographic determinants of uneven CDM development across countries, and has implications for developing countries in terms of international cooperation and national capacity building to effectively access the CDM
Despite efforts to stabilize CO_2 concentrations, it is possible that the climate system could respond abruptly with catastrophic consequences. Intentional intervention in the climate system to avoid or ameliorate such consequences has been proposed as one possible response, should such a scenario arise. In a one-week study, the authors of this report conducted a technical review and evaluation of proposed climate engineering concepts that might serve as a rapid palliative response to such climate emergency scenarios. Because of their potential to induce a prompt (less than one year) global cooling, this study concentrated on Shortwave Climate Engineering (SWCE) methods for moderately reducing the amount of shortwave solar radiation reaching the Earth. The study's main objective was to outline a decade-long agenda of technical research that would maximally reduce the uncertainty surrounding the benefits and risks associated with SWCE. For rigor of technical analysis, the study focused the research agenda on one particular SWCE concept--stratospheric aerosol injection--and in doing so developed several conceptual frameworks and methods valuable for assessing any SWCE proposal. Comment: 66 pp., 5 figs., published by Novim, Santa Barbara, Cal., revised reference
To understand global changes in the Earth system, scientists must generalize
globally from observations made locally and regionally. In land change science
(LCS), local field-based observations are costly and time consuming, and
generally obtained by researchers working at disparate local and regional
case-study sites chosen for different reasons. As a result, global synthesis
efforts in LCS tend to be based on non-statistical inferences subject to
geographic biases stemming from data limitations and fragmentation. Thus, a
fundamental challenge is the production of generalized knowledge that links
evidence of the causes and consequences of local land change to global patterns
and vice versa. The GLOBE system was designed to meet this challenge. GLOBE
aims to transform global change science by enabling new scientific workflows
based on statistically robust, globally relevant integration of local and
regional observations using an online social-computational and geovisualization
system. Consistent with the goals of Digital Earth, GLOBE has the capability to
assess the global relevance of local case-study findings within the context of
over 50 global biophysical, land-use, climate, and socio-economic datasets. We
demonstrate the implementation of one such assessment - a representativeness
analysis - with a recently published meta-study of changes in swidden
agriculture in tropical forests. The analysis provides a standardized indicator
to judge the global representativeness of the trends reported in the
meta-study, and a geovisualization is presented that highlights areas for which
sampling efforts can be reduced and those in need of further study. GLOBE will
enable researchers and institutions to rapidly share, compare, and synthesize
local and regional studies within the global context, as well as contributing
to the larger goal of creating a Digital Earth.
Three silicic calderas have been newly identified in northwest Nevada west of McDermitt caldera. This volcanism is interpreted to have formed during a short interval at 16.5-15.5 Ma, during the waning stage of Steens flood basalt volcanism after the initial impingement of the Yellowstone hot spot. New mapping demonstrates that the area affected by this mid-Miocene silicic volcanism is significantly larger than previously appreciated in the western U.S.
Seven tree-ring chronologies are used to reconstruct Teberda River (Northern Caucasus, Russia) smoothed runoff for May, July and August. Six chronologies were developed from Pinus sylvestris and one from Abies nordmanniana. Tree growth is significantly, but weakly, correlated with maximum temperatures (negatively) and relative humidity (positively) during summer. All possible combinations of seven predictors were tried to get the best result on the cross-validation. Two of three reconstructions showed high wavelet coherence with instrumental data on decadal timescales and were analysed for spectrum stability. Minima of moving trends at the end of the reconstructions along with weakening of decadal cycles may be a marker of significant change of Teberda River hydrological regime during the second half of the 20th century.
It is widely acknowledged that global warming will result in an increased extremality of hydrological phenomena. As for streamflow it is anticipated that duration of low-flow conditions and flood frequency will both increase. Approving this hypothesis by statistically evaluating daily runoff characteristics depends on the availability of long and homogeneous data series. The aim of this paper is to analyze the change of the average daily flows of the Danube at Bratislava for different subsets of the period 1876-2006. The statistical tests did not reveal any increase in the extremality of daily runoff over the period 1876-2006. On the contrary, variability of daily flows of the Danube River decreases. Over the last 30 years streamflows increased in the winter-spring season and decreased in the summertime, compared to the past periods. This can be explained by the higher air temperature in the headwaters. A warmer climate causes an earlier onset of snowmelt in the winter-spring season, thus less runoff is observed in the summer with higher rates of precipitation.
This paper is concerned with morphological change analysis in the old foreign concessions of Shanghai from 1969 to 2010. To that end, we use a series of 17 Landsat TM and Landsat ETM + images on which we estimate some feature parameters. The analysis of the resulting time series enables to isolate changes from traditional constructions to new buildings or gardens. Our results show that 70% of the old urban pattern was converted in modern high-rise buildings and green spaces.
This study has assembled a climatology of Southwest Pacific explosively developing cyclones, based on the European Centre for Medium-Range Weather Forecasts' ERA-Interim reanalysis data, over the 21-year period from 1989 to 2009. The recently developed 'combined explosive' expression, a refinement of the 'relative explosive' criterion, was used to identify cyclones deemed explosive with respect to both the drop in central pressure and the climatological pressure gradient. Over the period of analysis, 47 explosive cyclones were identified within the Southwest Pacific, equating to an average of 2.2 explosive events per year. Seasonally, explosive cyclones are most frequent during the winter months, while least frequent during the summer. Two case explosive systems are briefly considered, with their corresponding measures of intensity and scale placed into climatological perspective.
Wetlands in the Songhua River Basin in both 1995 and 2008 were mapped from land use/land cover maps generated from Landsat Thematic Mapper imagery. These maps were then divided into two categories, i.e. artificial wetland and natural wetland. From 1995 to 2008, the total area of wetland in the Songhua River Basin increased from 93 072.3 km2 to 99 179.6 km2 a net increase of 6107.3 km2. The area of natural wetland decreased by 4043.7 km2 while the area of artificial wetland increased by 10 166.2 km2. Swamp wetland and paddy field wetland became the dominant wetlands and the swamp wetland in the east of the Heilong River system and the north of the Wusuli River system disappeared, being transformed into paddy field wetland. The diversity of wetland landscape is worsening and the distribution of wetland landscape is becoming more unbalanced; the fragmentation of natural wetland has intensified whereas the patch connectivity of artificial wetland has increased. Changes in natural wetlands were primarily caused by climate and socio-economic changes, while changes in artificial wetland were mainly caused by the growth of population and gross domestic product.
Measurements of the global distribution of the tropospheric NO2 column densities have become available with the GOME (Global Ozone Monitoring Experiment) and SCIAMACHY (Scanning Imaging Absorption spectroMeter for Atmospheric Chartography) instruments. The spatial and temporal characters of NO2 over the North-South Transect of Northeast Asia (NSTNA) was analyzed using monthly averaged tropospheric NO2 column densities from GOME and SCIAMACHY measurements taken from April 1996 to December 2010. In addition to NO2 (1996-2010) column densities data, land-cover data and characters of NO2 concentration over different ecosystem have been analyzed over the NSTNA. The results indicated that the tropospheric NO2 column densities over the region show distinct regional and seasonal variation characteristics for between 1996 and 2009. The highest concentration was in winter and lowest in autumn. The data also presents zonal distribution and decreasing from northern to southern. Under the influence of the urbanization process, the highest NO2 column densities appeared at cities and metropolitan areas which are located in the north plain of China and the southern areas of the NSTNA. Moreover the lowest column densities appeared at the northern areas of the NSTNA. The tropospheric NO2 column densities have shown significant differences over other ecosystems. In addition, the higher NO2 column density was found over forest and grass land while lower values over lake, tundra and semi-desert. There are different characteristics in five land use types along with the NO2 column densities increasing year by year. The highest values appeared in winter over the forest, grass, lake and tundra while in summer over the semi-desert.
Two dominant modes of the spatial-temporal evolution of the chlorophyll (CHL) over the western Pacific were revealed for the period from 1998 to 2010 using season-reliant Empirical Orthogonal Function (S-EOF) analysis method. The results showed that the first two dominant modes of CHL accounted for 43.8% of the total variance, corresponding to ENSO turnabout and post-ENSO years respectively. Besides, SEOF analysis was also applied to sea surface temperature (SST) and sea level anomaly (SLA). The seasonally evolving patterns of CHL on seasonal timescale was closely related to the patterns of SST and SLA associated with ENSO, with the consistent turning tendency of the principle component. To further distinguish the relationship between the seasonal evolution of CHL and ENSO, the lead-lag correlation coefficients were calculated between MEI and the principal components of the leading two modes of CHL. The first mode of CHL was primarily associated with the ENSO development and prediction while the second mode of CHL followed the peak of ENSO, and might be viewed as a response to ENSO.
In this paper, Xunke County was studied using HJ-1A hyperspectral data for monitoring vegetation restoration after forest fires. The pre-processing procedure including data format conversion, image mosaicing and atmospheric correction. Support vector machine classification was used to perform surface feature identification based on the extracted spectral end-members. On that basis, the image area was divided into seven categories and statistical analysis of classification types was performed. The results showed that HJ-1A hyperspectral data had great potential in fine classification of surface features and the accuracy of classification was 91.8%. The mild and severe fire-affected area extraction provided useful reference for disaster recovery monitoring. Furthermore, the distinction between coniferous forest and broadleaved forest can offer useful information for forest fire prevention and early warning to some extent.
According to radiation transfer equation (RTE), it is an ill-conditioned problem to obtain land surface temperature (LST) accurately from the HJ-1B thermal infrared channel. Several algorithms have been proposed to resolve this problem. However, some accurate inputs (e.g. atmospheric parameters and land surface emissivity) always inaccessible to common users are indispensable to their applications. An innovative approach (named MTSC method) based on multi-temporal data was described in this paper, by means of which the LSTs are able to be estimated readily and directly from the radiometrically corrected thermal images, even without any other accurate information. To demonstrate its capability, four HJ-1B images (acquired on Nov 28, Dec 10, Dec 18 and Dec 22, 2011, respectively) mainly covering the Pearl River Delta region were selected for LSTs estimation. The LSTs retrieved by the MTSC method were then compared with the near time MODIS surface temperature products, and the samples were collected through a proper procedure. The preliminary assessments demonstrated that accurate results were obtained by using this new method. For example, for the retrieved results of Dec 22, the systematic errors for land cover and sea area were approximate to 1K and 0.5K, respectively. Further comparisons show that the temporal influence was negligible in this experiment, mainly because of the moderate impacts arisen from the atmospheric variation on the surface thermal property, which was acceptable for the MTSC method. However, modifications and improvements are still necessary to enable the full usage of this new approach.
The research of performances of hydraulic mechanical depends on static
complete characteristic curves, which have great difference compared
with the actual work condition and have accidents potential. So we need
a new way to compute the dynamic system, which is more reasonable. So
the method to couple one dimensional simulation and three dimensional
CFD analysis based on Flowmaster and Fluent is explored, and the dynamic
characteristics and internal flow of the pumping system are analyzed.
First, a pipe system model is created in Flowmaster and a pump model is
created in Fluent; then VB code and scheme code are used to realize the
automated operation for Flowmaster and Fluent; at last, the exchange of
data between these two parts is realized by an interface program. In
this paper, the interaction between pumps and pipe system are analyzed
by coupling one-dimensional and three-dimensional simulations. This
study would be helpful to identify the influences of the rapid
adjustment process on stability of system and provide guides for design
of pump system.
'Retrospective views on our planet's future' – This was the theme of a tandem of meetings held by Past Global Changes (PAGES; http://www.pages-igbp.org), a project of the International Geosphere-Biosphere Programme (IGBP). It reflects the philosophy of PAGES and its community of scientists that the past holds the key to better projections of the future. Climatic and environmental evidence from the past can be used to sharpen future projections of global change, thereby informing political and societal decisions on mitigation and adaptation.
Young scientists are critical to the future of this endeavour, which we call 'paleoscience'. Their scientific knowledge, interdisciplinarity, international collaboration, and leadership skills will be required if this field is to continue to thrive. Meanwhile, it is also important to remember that science develops not only by applying new strategies and new tools to make new observations, but also by building upon existing knowledge. Modern research in paleoscience began around fifty years ago, and one could say that the third generation of researchers is now emerging. It is a wise investment to ensure that existing skills and knowledge are transferred to this generation. This will enable them to lead the science towards new accomplishments, and to make important contributions towards the wider field of global change science.
Motivated by such considerations, PAGES organized its first Young Scientists Meeting (YSM), held in Corvallis (Oregon, USA) in July 2009 (http://www.pages-osm.org/ysm/index.html). The meeting took place immediately before the much larger 3rd PAGES Open Science Meeting (OSM; http://www.pages-osm.org/osm/index.html). The YSM brought together 91 early-career scientists from 21 different nations. During the two-day meeting, PhD students, postdoctoral researchers, and new faculty met to present their work and build networks across geographical and disciplinary borders. Several experienced and well-recognized researchers tutored this conference, and gave assistance to young scientists by offering advice on publication, promotion, outreach processes, and data management. At the subsequent OSM, the young scientists had the opportunity to present their results to a larger community, and to build networks with their senior colleagues.
In a friendly and classroom-like atmosphere, the research presented during the YSM was of a remarkably high quality, and merited publication in this special issue. The 23 short proceedings papers are first-authored by YSM attendees, and based on their presented work and the associated discussions. Consistent with the spirit of the YSM, the core of the guest editor team consisted of YSM early-career scientists, while members of the wider scientific community reviewed the papers.
Studies presented in this issue cover a large range of topics. Paleoclimatic and paleoenvironmental research is always seeking new natural archives and improved proxies, and so some papers focus on reconstruction methodologies and the interpretation and calibration of proxies. Other papers present a variety of modeling approaches, such as climate system modeling, forward modeling, or ecosystem modeling. Still others focus on reconstructions from marine (foraminifera, diatoms, corals) or continental (tree rings, speleothems, ice cores) archives, or on understanding the dynamics of the Earth system and the feedbacks between its various components. The studies presented span timescales ranging from the past 200,000 years to the last few decades, and consider changes in natural phenomena such as the hydrological cycle and the El Niño-Southern Oscillation, as well as local- and regional-scale interaction of humans with the environment. The papers presented in this special issue therefore reflect current challenges in paleoscience research: understanding natural variability on both long and short time scales, and monitoring anthropogenic impacts which range from historic landscaping to more recent pollution.
The concept and format of the 1st PAGES YSM worked very well, and created a high degree of enthusiasm and stimulation among the participants (as is demonstrated by this special issue). The 2nd YSM is therefore firmly planned to take place in 2013, back-to-back with the 4th PAGES OSM.
Crucial and gratefully acknowledged contributions to the success of the YSM were made by the numerous co-sponsors (see logos below), who provided the financial basis for the YSM and supported the attendance of many early-career researchers from various parts of the world. Furthermore, we cordially thank all reviewers for shaping this proceeding issue with their insightful and helpful reviews.
Recently, the design of RF power amplifiers (PAs) for modern wireless
systems are faced with a difficult tradeoff for example, cellphone;
battery lifetime is largely determined by the power efficiency of the PA
and high spectral efficiency which have ability to transmit data at the
highest possible rate for a given channel bandwidth. This paper presents
the design a multi stage class AB power Amplifier with high power added
efficiency (PAE) and acceptable linearity for the WLAN applications. The
open-circuited third harmonic control circuit enhances the efficiency of
the PA without deteriorating the linearity of class-AB mode of the PA.
The voltage and current waveforms are simulated to evaluate the
appropriate operation for the modes. The effectiveness of the proposed
controller has been verified by comparing proposed method with another
methods using simulation study under a variety of conditions. The
proposed circuit operation for a WLAN signals delivers a power-added
efficiency (PAE) of 37.6% is measured at 31.6-dBm output power while
dissipating 34.61 mA from a 1.8V supply. Finally, the proposed PA is
show a good and acceptable result for the WLAN system.
Coal fires are a common and serious problem in most coal producing countries. Coal fires could not only lead to a huge loss of non-renewable energy resources, but it also can cause many environmental problems such as GHG emission, land subsidence and increment of surface temperature. So it is very important to monitor the dynamic changes of coal fires. As far as large scale coal field, remote sensing provided researchers with a new and useful technique for coal fire detection. This paper developed a research over coal fire spreading direction using a multi-temporal TIR remote sensing approach. The results successfully showed that the direction of coal fire spreading and predicted the coal fire direction of development on a regional scale or on a whole coal field scale, and a quantitative analysis of coal fires was made in the research. The results showed that the coal fires had an average annual increase of 0.5 million square meters from 1999 to 2006, and the TIR remote sensing proved to be an available tool for coal fire mapping and prediction of coal fire development.
We present an analysis of caldera evolution at Miyakejima in 2000. The caldera changed its structure from piston to funnel subsidence during its growth. The successive subsidence of the central block induced landslides at the caldera wall, which successively enlarged the diameter of the caldera.
The Source Region of Three Rivers (SRTR) has very important ecological functions which form an ecological security barrier for China's Qinghai-Tibet plateau. As the biggest nationally occuring nature reserve region in China, the ecological environment here is very fragile. In SRTR the grassland coverage is an effective detector to reflect the ecological environment condition, because it records the changing process of climatic and environmental sensitively. In recent years SRTR has been suffering pressures from both nature and social pressures. With MODIS data the study monitored the grassland coverage continuously in SRTR from 2000 to 2012. The density-model was adapted to estimate grassland coverage degree firstly. Then the degree of change and the change intensity, change type were used to judge the grassland coverage change trend comprehensively. For grassland coverage there was natural change annual or within the year, and the degree of change was used to judge if there was change or not. The grassland has another important characteristic, annual fluctuation, and it can be differed from sustained changes with change type. For grassland coverage, such continuous change, like improvement or degradation, and to what extent, has more guidance sense on specific production practice. On the base of change type and degree of change, change intensity was used to identify the change trend of the grassland coverage. The analysis results from our study show that steady state and fluctuation are two main change trends for the vegetation coverage in SRTR from 2000 to 2012. The conclusion of this paper can provide references in response to environment change research and in the regional ecological environmental protection project in SRTR.
Currently, one of the major issues is to transform different remote sensing observations into a global reference for sustainable global-scale glacier change monitoring. In order to put glacier changes into a broader temporal context, it is desirable to extend the glacier observation time as far back as possible. In this paper, we present a case study of registering ASTER satellite stereo images to ICESat GLAS laser altimetry data, by matching terrain features identified from the ICESat measurements to those corresponding in the ASTER images. Features like ridges and nunatak can be extracted from ICESat data, and these features can also be measured in ASTER stereo images. A rigid body transformation (3 translations, 3 rotations) is applied for an optimal fit of these two sets of feature points. After transforming the ASTER photogrammetry measurements into the ICESat reference frame, we compute elevation change rates at each ICESat point by using a linear interpolation to obtain an estimate of surface elevation from ASTER. The surface firn/ice density model is used in converting the elevation changes to mass changes. Our study indicates that Lambert Glacier is close to being in mass balance between 2002 and 2012.
Heavy and intense precipitation which fell in just a few hours across the western, north-western and northern Slovenia on 18 September 2007, caused quick rise of river discharges especially in the region of Baška grapa, Davča, the Cerkljansko and Škofja Loka hills. In that area the streams caused huge destruction on infrastructure, homes, business buildings and other property. More than 300 mm of rain was recorded on some precipitation measurement stations. The return period of the highest precipitation was more than 100 years. The amount of precipitation decreased from the west to the east of the country where above 100 mm of precipitation was recorded and torrential streams and rivers flooded in the region of Karavanke and foothills of the Kamnik-Savinja Alps, Kranj and Domžale fields, the Tuhinj valley and extensive Celje region. Observed discharges of streams and rivers on the most affected area exceeded periodical maximum discharges. The simulation of flood hydrograph for Železniki was done by HEC-1 model. The return period of floods was more than 100 years. Besides flooding many landslides were triggered. The result of this catastrophe was enormous economic damage and loss of six people's lives.
The Rapid Inventory Collection System (RICS) is a vehicular data collection system (image and GPS) used for building/infrastructure damage and inventory assessment. The system consists of Ethernet cameras attached to a tripod mounted on a motor vehicle, a GPS receiver and software written in C++. RICS was deployed following the 2009 Victorian Bushfires and the collected data was used by the Victorian Bushfires Royal Commission for the impact assessment (field survey) which quantified the extent and severity of the damage caused to residential buildings by the fire-storm. The regions of Kilmore East, Murrindindi, Churchill, Maiden Gully – Bendigo and Bunyip had nearly 5400 residential structures within the fire perimeter. Analysis utilising both aerial and vehicular (RICS) imagery indicates that just over 2100 homes were destroyed and an additional 800 received minor damage.
EARLINET, the European Aerosol Research Lidar Network, is the best tool to investigate the horizontal and vertical transport of aerosols over Europe. Within the network, particular attention is devoted to Saharan dust events monitoring. An alert system has been established in order to perform devoted measurements in case of intrusions of desert particles on European continent. Starting from data collected within EARLINET since May 2000, a first statistical analysis of the aerosol vertical distribution on European scale during Saharan dust outbreaks, has been performed. These results highlights the fundamental role that EARLINET can have for the study of impact of Saharan dust on European scale. The current 5-year EU project EARLINET-ASOS, started in March 2006, will enhance the operation of the network through the improvement of the instruments and of the temporal coverage, and of the data analysis procedures.
This study extends upon the results of  to include the modeling of Land use/ Land cover (LULC). This study looks at the changes that occurred from 2010 to 2030 in Tikrit district, Iraq by predicting LULC for the year target 2030 by using the classified images for two points of time (2000 – 2010) as a foundation for the modeling process. The projected map, in comparison with 2010 LULC map, shows a significant decrease in vegetation area (45.11 km2) which must be regulated in order to maintain a green environment, and increase in the urban area (58.42 km2) which should be monitored to have sustainable development and control the eco-environment degradation. Also, in this study, it is shown clearly that the use of Geographic Information System (GIS) and remote sensing (specially IDRISI software) in modeling LULC is a suitable approach to understand the future pattern.
The European Consortium for Ocean Drilling Program (ECORD), the Canadian Consortium for Ocean Drilling (CCOD), the Network of the Universités du Québec (UQ), the Université du Québec à Montréal (UQAM) and GEOTOP sponsored, in 2010, a summer school entitled 'Ocean and climate changes in polar and sub-polar environments'. This summer school took place from 27 June to 12 July in Rimouski, Québec city and Montréal (Quebec, Canada) and was attended by nineteen students and postdoctoral fellows from seven countries: Canada, France, Germany, UK, Serbia, Portugal and the USA. Lectures, hands-on laboratory exercises and laboratory visits were conducted at the Institut des Sciences de la Mer de Rimouski (ISMER), Institut National de la Recherche Scientifique – Centre Eau Terre Environnement (INRS-ETE) and UQAM, in addition to two field trips and a short geological and geophysical cruise on board the R/V Coriolis II in the St Lawrence Estuary and Saguenay Fjord. During the summer school, more than twenty researchers gave lectures on the use of several paleoceanographic and geophysical techniques to reconstruct ocean and climate changes in polar and sub-polar environments. Some of these lectures are presented as short review papers in this volume. They are intended to portray a brief, but state-of-the-art overview of an array of techniques applied to Arctic and sub-Arctic environments, as well as the geological background information needed by the summer school participants to put the scientific expedition and fieldwork into context. The volume begins with a view on the great challenges and key issues to be addressed in the Arctic Ocean (Stein) in the forthcoming years and is followed by a review (O'Regan) on Late Cenozoic paleoceanography of the Central Arctic. The two subsequent papers (St-Onge et al and de Vernal et al) deal with the oceanographic, paleoceanographic and geological context of the Saguenay Fjord, and St Lawrence Estuary and Gulf. The subsequent set of papers review the use of planktonic foraminifers (Eynaud), diatoms (Crosta) and dinocysts (de Vernal and Rochon) in polar or sub-polar environments. These articles are followed by a paper on transfer functions (Guiot) summarizing the different approaches used to reconstruct past environmental conditions from micropaleontological proxy data. Two papers on geochemical and isotopic proxies are then presented and related to either foraminifera isotopic records (Hillaire-Marcel) in high northern latitudes or changes in ocean circulation and weathering inputs derived from radiogenic isotopes (Frank). The volume concludes with a paper on the application of visible/near infrared derivative spectroscopy to Arctic sediments (Ortiz). All the papers published in this volume benefited from the reviews of at least two reviewers, whom we thank for their valuable time and comments. We also thank the crew of the Coriolis II, and the many scientists, participants and volunteers who contributed to the summer school and made it a great success. In addition to GEOTOP and UQAM, the following institutions contributed to the organization of the summer school: ISMER, INRS-ETE, the Geological Survey of Canada, and REFORMAR. Finally, we thank Hélène Gaonac'h (UQAM) for coordinating the summer school and Anne de Vernal (UQAM) for her leadership throughout the summer school. Editors Guillaume St-Onge Canada Research Chair in Marine Geology, Institut des sciences de la mer de Rimouski (ISMER) & GEOTOP Research Center, 310 allée des Ursulines, Rimouski, Québec, Canada, G5L 3A1 Cristina Veiga-Pires FCMA - CIMA, Universidade do Algarve, Campus de Gambelas, 8000-117 Faro, Portugal Sandrine Solignac GEOTOP, Université du Québec à Montréal, PO Box 8888, succursale 'centre ville' Montréal, QC, H3C 3P8 Canada Scientists who contributed to the summer school: Hans Asnong (UQAM/GEOTOP, Canada) Gilles Bellefleur (Geological Survey of Canada-Ottawa, Canada) Anne de Vernal (UQAM/GEOTOP, Canada) Mathieu Duchesne (Geological Survey of Canada-Québec, Canada) Frédérique Eynaud (EPOC/Universite Bordeaux I, France) Pierre Francus (INRS-ETE/GEOTOP, Canada) Martin Frank (IFM-GEOMAR, Germany) Yves Gélinas (Concordia/GEOTOP, Canada) Joël Guiot (CEREGE, France) Claude Hillaire-Marcel (UQAM/GEOTOP, Canada) Patrick Lajeunesse (University Laval, Canada) Jean-François Lemieux (Courant Institute of Mathematical Sciences, New York University, USA) Guillaume Massé (LOCEAN/Institut Pierre-Simon Laplace, France) Matt O'Regan (Cardiff University, UK) Joseph Ortiz (Kent State University, USA) Frank Rack (University Nebraska-Lincoln, USA/ANDRILL Science Management Office) Taoufik Radi (UQAM/GEOTOP, Canada) André Rochon (ISMER-UQAR/GEOTOP, Canada) Ruediger Stein (Alfred Wegener Institute, Germany) Guillaume St-Onge (ISMER-UQAR/GEOTOP, Canada) Bjorn Sundby (ISMER-UQAR, Canada)
An analysis of the ENVISAT advanced synthetic aperture radar (ASAR) observations of the area hit by the 2011 Japan tsunami is presented. The height of the tsunami waves was sufficient to cause widespread inundation of coastal areas. The SAR acquisitions were performed on February 19 (20 days before the tsunami) and March 21 (ten days after the tsunami) in interferometric mode so that not only the information regarding the intensity of the radar signals but also the complex coherence was used. The interpretation of the available data has allowed researchers to detect flooded areas. Though the post-tsunami acquisition is a bit late for the fixed 30-day observation cycle of ENVISAT ASAR sensor, and the spatial resolution of ASAR is relatively low, valuable information regarding the damage was still retrieved. These interpretations have been validated by a series of optical images, which served as benchmarks.
This study compares the convenience of temporary housing complexes in the Iwate Prefecture following the 2011 Tohoku Earthquake. The study was targeted at three major cities in the southern coastal area of Iwate Prefecture, namely, Kamaishi, Ofunato, and Rikuzen- Takata, that were most heavily struck by the earthquake-triggered tsunami.
We conducted a network analysis in geographical information system software using the coordinate data of several daily infrastructures. Temporary housing complexes within the defined service area of each infrastructure were assigned a score of 1.00. The main findings are summarized below:
1) The temporary housing complexes in Rikuzen-Takata City were less accessible to infrastructures (as evidenced by the low coverage area of 1.00 scores) than the other investigated cities.
2) The scores of Kamaishi City and Ofunato City were statistically similar, but complexes in Ofunato City were surrounded by slightly more infrastructures (greater coverage area of 1.00 scores) than Kamaishi City.
3) We identified more than the predicted number of blank areas in the targeted areas. Thus, we consider that support services for people living in such areas are urgently required, especially in the realms of daily shopping, banking, and healthcare.
The 4th International Conference on Energy & Environment 2013
(ICEE2013) was organized by the Universiti Tenaga Nasional (UNITEN) to
provide a platform for creating and sharing ideas among engineers,
researchers, scientists, industrialists and students in sustainable
green energy and technologies. The theme 'Shaping a Sustainable Future
through Advancement in Green Energy Technology' is in line with the
University's vision to be a leading global energy university that shapes
a sustainable future.
The general scopes of the conference are renewable energy, smart grid,
green technology, energy policies and economics, sustainable green
energy and environment, sustainable education, international cooperation
and innovation and technology transfer. Five international keynote
speakers delivered their speeches in specialized areas of green energy
technology and sustainability. In addition, the conference highlights
several special parallel sessions by notable invited presenters in their
niche areas, which are:
Hybrid Energy Power Quality & Distributed Energy Smart Grid
Nuclear Power & Technologies Geohazard Management Greener
Environment for Sustainability Advances in Computational Fluid Dynamics
The research papers presented in ICEE2013 are included in this volume of
IOP Conference Series: Earth and Environmental Science (EES). EES is
abstracted and indexed in SCOPUS, GeoBase, GeoRef, Compendex, Inspec,
Chemical Abstracts Service, NASA Astrophysics Data System, and
International Nuclear Information System (INIS).
With the comprehensive programme outline, the organizing committee hopes
that the ICEE2013 was a notable intellectual sharing session for the
research and academic community in Malaysia and regionally. The
organizing committee expresses gratitude to the ICEE2013 delegates for
their great support and contributions to the event.
Microstructural analysis of quartz grains in sandstones revealed preferred directions which define and influence porosity and permeability anisotropy in oil and gas reservoirs In this research, we investigated the Upper Jurassic sandstone reservoir sediments from 14 wells in Kazanskoe field. The authors studied: the orientation of elongated quartz grains, and intergranular fracture within grains, as well as the pore space in oriented thin sections of sandstones. The analysis of elongated quartz grains in the bedding plane showed three main types of preferred directions in quartz grain orientation along different axes in sandstone reservoirs. Obtained results allow identifying a variability of facies and dynamic depositional environment for Upper Jurassic sandstone formation. Subsequently, these results can be used in field modeling, as well as pattern optimization of injection and production wells.
The moderate temperature increase of 0.74 °C in the 20th century has caused latitudinal and altitudinal range shifts in many species including mammals. Therefore, given the more dramatic temperature increase predicted for the 21st century, we can therefore expect even stronger range shifts as well. However, European mammals are already faced with other anthropogenic pressures, notably habitat loss, pollution, overexploitation, and invasive species, and will have to face the combined challenge posed by climate change in a landscape highly influenced by human activities. As an example of the possible consequences of land use, invasive species, and climate change for the regional-scale mammal species composition, we here focus on the potential 21st century changes to the mammal fauna of Denmark. Supported by species distribution modelling, we present a discussion of the possible changes to the Danish mammal fauna: Which species are likely to become locally extinct? Which new species are most likely to immigrate? And, what is the potential threat from invasive species? We find that future climate change is likely to cause a general enrichment of the Danish mammal fauna by the potential immigration of seventeen new species. Only the northern birch mouse (Sicista betulina) is at risk of extinction from climate change predicted. The European native mammals are not anticipated to contribute to the invasive-species problem as they coexist with most Danish species in other parts of Europe. However, non-European invasive species are also likely to enter the Danish fauna and may negatively impact the native species.
This study examines the potential impact of 21st century sea-level rise on Aarhus, the second largest city in Denmark, emphasizing the economic risk to the city's real estate. Furthermore, it assesses which possible adaptation measures that can be taken to prevent flooding in areas particularly at risk from flooding. We combine a new national Digital Elevation Model in very fine resolution (~2 meter), a new highly computationally efficient flooding algorithm that accurately models the influence of barriers, and geospatial data on real-estate values to assess the economic real-estate risk posed by future sea-level rise to Aarhus. Under the A2 and A1FI (IPCC) climate scenarios we show that relatively large residential areas in the northern part of the city as well as areas around the river running through the city are likely to become flooded in the event of extreme, but realistic weather events. In addition, most of the large Aarhus harbour would also risk flooding. As much of the area at risk represent high-value real estate, it seems clear that proactive measures other than simple abandonment should be taken in order to avoid heavy economic losses. Among the different possibilities for dealing with an increased sea level, the strategic placement of flood-gates at key potential water-inflow routes and the construction or elevation of existing dikes seems to be the most convenient, most socially acceptable, and maybe also the cheapest solution. Finally, we suggest that high-detail flooding models similar to those produced in this study will become an important tool for a climate-change-integrated planning of future city development as well as for the development of evacuation plans.
Extreme sea levels are likely to increase in the future with an expected accelerated rise in mean sea level and through possible changes in storminess. Society is becoming more vulnerable to extreme sea levels due to considerable growth in human populations and economy at the coastal zone and this is particularly true for Western Australia, the fastest growing Australian state or region. This paper describes a novel approach used to estimate future changes in extreme sea level around the southwest coastline of Western Australia. Probabilities of extreme sea level for the present climate have been estimated using a 60 year hindcast of sea levels. The impact of climate change has been explored by adding a range of mean sea level rise projections to these probabilities. Estimates of possible future changes in recurrence intervals every decade over the 21st century are presented, showing that climate change has the potential to significantly reduce current average recurrence intervals and that the amount of reduction varies significantly around the coastline.
In this paper we examined the potential impacts of predicted climatic changes on the flora and vegetation in Denmark using data from a digital database on the natural vegetation of Europe. Climate scenarios A2 and B2 were used to find regions with present climatic conditions similar to Denmark's climate in the year 2100. The potential natural vegetation of Denmark today is predominantly deciduous forest that would cover more than 90% of the landscape. Swamps, bogs, and wet forest would be found under moist or wet conditions. Dwarf shrub heaths would be naturally occurring on poor soils along the coast together with dune systems and salt-marsh vegetation. When comparing the natural vegetation of Denmark to the vegetation of five future-climate analogue areas, the most obvious trend is a shift from deciduous to thermophilous broadleaved forest currently found in Southern and Eastern Europe. A total of 983 taxa were recorded for this study of which 539 were found in Denmark. The Sørensen index was used to measure the floristic similarity between Denmark and the five subregions. Deciduous forest, dwarf shrub heath, and coastal vegetation were treated in more detail, focusing on potential new immigrant species to Denmark. Finally, implications for management were discussed. The floristic similarity between Denmark and regions in Europe with a climate similar to what is expected for Denmark in year 2100 was found to vary between 48–78%, decreasing from North to South. Hence, it seems inevitable that climate changes of the magnitudes foreseen will alter the distribution of individual species and the composition of natural vegetation units. Changes, however, will not be immediate. Historic evidence shows a considerable lag in response to climatic change under natural conditions, but little is known about the effects of human land-use and pollution on this process. Facing such uncertainties we suggested that a dynamic strategy based on modeling, monitoring and adaptive management is adopted. Modeling techniques can be constantly improved, but will never be perfect and should therefore be linked to a fine-masked network of observatories to check model predictions and feed empirical data back into the models for calibration and further development.
In the last few years, rapid improvements have been made to improve the
quality of high-temperature superconductors. Amongst the high
temperature superconductors, the Bi-based (BSCCO) consists of interest
for various applications.
Bi2Sr2CaCu2O8 (Bi-2212) have
been used to make superconducting tapes and wires. Unlike conventional
compound superconductors, the critical current, Ic of oxide
superconducting tapes in the elastic strain is generally almost constant
and degrades suddenly when it is subject to mechanical force by a strain
beyond the limit. In this research, the Bi-2212 samples were prepared by
solid state reaction method. Precursors oxide powders were pressed to
pallets under hydrostatic pressure around 7 tons or 70 000 psi and then
sintered at temperature of 850°C for 24 hours. The effect of
radiation before and after irradiation on mechanical and superconducting
properties of the samples was studied. Irradiation was carried out with
a beam of 3 MeV, current of 10 mA and radiation dose of 100 and 200
KGray. The x-ray diffraction analysis is used to verify Bi-2212 phase.
The samples were also characterized through electrical properties by
using the four-point probe method. The microstructure of the samples was
studied by using the scanning electron microscopy (SEM), and compression
test was also conducted using the stress-strain relationship. The phase
structure and electrical properties of the samples degrade slightly with
irradiation exposure. Nevertheless the microstructure showed that when
initial electron radiation dose was increased up to 100 kGray, the grain
growth, texture and core density improved slightly but the grain growth,
size and core density begin to deteriorate after the electron radiation
dose is increased to 200 kGray. This may be due to the formation of
larger size defects within the microstructure of the Bi-2212 phase as
the radiation dose increases.
We present 22 U-series ages for a stalagmite from north-western Cuba based on multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS) and thermal ionisation mass spectrometry (TIMS). Our results reveal that the stalagmite continuously grew within the last ~1400a. Low uranium content of the sample and thus, extremely low 230Th concentrations limit the precision and accuracy of 230Th/U-dating by TIMS. Samples measured by MC-ICPMS show a high variability of 232Th content along the growth axis with some sections significantly affected by initial 230Th from a detrital phase. An a-priori bulk earth ratio for (238U/232Th) cannot be used to accurately account for this initial 230Th. Using an age model based on the 230Th/U ages determined on samples with low or negligible 232Th concentration, we find that the (238U/232Th) activity ratio of the detrital phase is an order of magnitude larger than the bulk earth value, indicating the importance of an accurately determined correction factor.
The 26th IAHR Symposium on Hydraulic Machinery and Systems, will be held in Beijing, China, 19–23 August 2012. It is jointly organized by Tsinghua University, State Key Laboratory of Hydro Science and Hydraulic Engineering, China, Jiangsu University, Xi'an University of Technology, China Agricultural University, National Engineering Research Center of Hydropower Equipment and Dongfang Electric Machinery Co., Ltd. It is the second time that China hosts such a symposium.
By the end of 2011, the China electrical power system had a total of 1 050 GW installed power, out of which 220 GW was in hydropower plants. The energy produced in hydropower facilities was 662.6 TWh from a total of 4,720 TWh electrical energy production in 2011. Moreover, in 2020, new hydropower capacities are going to be developed, with a total of 180 GW installed power and an estimated 708 TWh/year energy production. And in 2011, the installed power of pumped storage stations was about 25GW. In 2020, the data will be 70GW. At the same time, the number of pumps used in China is increasing rapidly. China produces about 29,000,000 pumps with more than 220 series per year. By the end of 2011, the Chinese pumping system has a total of 950 GW installed power. The energy consumed in pumping facilities was 530 TWh in 2011. The pump energy consumption accounted for about 12% of the national electrical energy production. Therefore, there is a large market in the field of hydraulic machinery including water turbines, pump turbines and a variety of pumps in China. There are also many research projects in this field. For example, we have conducted National Key Research Projects on 1000 MW hydraulic turbine, and on the pump turbines with high head, as well as on the large capacity pumps for water supply.
Tsinghua University of Beijing is proud to host the 26th IAHR Symposium on Hydraulic Machinery and Systems. Tsinghua University was established in 1911, after the founding of the People's Republic of China. It was molded into a polytechnic institute focusing on engineering in the nationwide restructuring of universities and colleges undertaken in 1952. At present, the university has 14 schools and 56 departments with faculties in science, engineering, humanities, law, medicine, history, philosophy, economics, management, education and art. The University now has over 25 900 students, including 13 100 undergraduates and 12 800 graduate students. As one of China's most renowned universities, Tsinghua has become an important institution for fostering talents and scientific research.
The International Association of Hydro-Environment Engineering and Research (IAHR) particularly promotes the advancement and exchange of knowledge through working groups, specialty symposia, congresses, and publications on water resources, river and coastal hydraulics, risk analysis, energy, environment, disaster prevention, and industrial processes.
The IAHR Committee on Hydraulic Machinery and Systems deals with the advancement of technology associated with the understanding of steady and unsteady flow characteristics in hydraulic machinery and conduit systems connected to the machinery. The technology elements include the fluid behaviour within machine components, hydro-elastic behaviour of machine components, cavitation and two phase flow in turbines and pumps, hydraulic machine and plant control systems, the use of hydraulic machines to improve water quality, and even considerations to improve fish survival in their passage through hydro plants. The main emphases of the IAHR Committee on Hydraulic Machinery and Systems are to stimulate research and understanding of the technologies associated with hydraulic machinery and to promote interaction between the machine designers, machine users, the academic community, and the community as a whole. Hydraulic machinery is both cost effective and environmentally friendly. The goals of the IAHR Committee on Hydraulic Machinery and Systems are to improve the value of hydraulic machinery to the end user, to the societies, and to improve societies understanding and appreciation of that value.
The series of IAHR Symposia on Hydraulic Machinery and Cavitation started with the 1st edition in Nice, France, 1960. For the past decade, all the symposia have focused on an extended portfolio of topics under the name of 'Hydraulic Machinery and Systems', such as the 20th edition in Charlotte, USA, 2000, the 21st in Lausanne, Switzerland, 2002, the 22nd in Stockholm, Sweden, 2004, the 23rd in Yokohama, Japan, 2006, the 24th in Foz do Iguassu, Brasil, 2008, and the 25th in Timisoara, Romania, 2010.
The 26th IAHR Symposium on Hydraulic Machinery and Systems brings together more than 250 scientists and researchers from 25 countries, affiliated with universities, technology centers and industrial firms to debate topics related to advanced technologies for hydraulic machinery and systems, which will enhance the sustainable development of water resources and hydropower production. The Scientific Committee has selected 268 papers, out of 430 abstracts submitted, on the following topics: (i) Hydraulic Turbines and Pumps, (ii) Sustainable Hydropower, (iii) Hydraulic Systems, (iv) Advances in Computational and Experimental Techniques, (v) Application in Industries and in Special Conditions, to be presented at the symposium and to be included in the proceedings.
All the papers, published in this Volume 15 of IOP Conference Series: Earth and Environmental Science, have been peer reviewed through processes administered by the editors of the 26th IAHR Symposium on Hydraulic Machinery and Systems proceedings, those are Yulin Wu, Zhengwei Wang, Shuhong Liu, Shouqi Yuan, Xingqi Luo and Fujun Wang.
We sincerely hope that this edition of the symposium will be a significant step forward in the worldwide efforts to address the present challenges facing the modern Hydraulic Machinery and Systems.
Professor Yulin Wu
Chairman of the Organizing Committee
26th IAHR Symposium on Hydraulic Machinery and Systems
Aimed at ancient architectures which own the characteristics of huge data quantity, fine-grained and high-precise, a 3D fine management and visualization method for ancient architectures based on the integration of 2D and 3D GIS is proposed. Firstly, after analysing various data types and characters of digital ancient architectures, main problems and key technologies existing in the 2D and 3D data management are discussed. Secondly, data storage and indexing model of digital ancient architecture based on 2D and 3D GIS integration were designed and the integrative storage and management of 2D and 3D data were achieved. Then, through the study of data retrieval method based on the space-time indexing and hierarchical object model of ancient architecture, 2D and 3D interaction of fine-grained ancient architectures 3D models was achieved. Finally, take the fine database of Liangyi Temple belonging to Wudang Mountain as an example, fine management and visualization prototype of 2D and 3D integrative digital ancient buildings of Liangyi Temple was built and achieved. The integrated management and visual analysis of 10GB fine-grained model of the ancient architecture was realized and a new implementation method for the store, browse, reconstruction, and architectural art research of ancient architecture model was provided.
The Qinghai-Tibetan Plateau is characterised by a very strong relief which affects albedo retrieval from satellite data. The objective of this study is to highlight the effects of sub-pixel topography and to account for those effects when retrieving land surface albedo from geostationary satellite FengYun-2D (FY-2D) data with 1.25km spatial resolution using the high spatial resolution (30 m) data of the Digital Elevation Model (DEM) from ASTER. The methodology integrates the effects of sub-pixel topography on the estimation of the total irradiance received at the surface, allowing the computation of the topographically corrected surface reflectance. Furthermore, surface albedo is estimated by applying the parametric BRDF (Bidirectional Reflectance Distribution Function) model called RPV (Rahman-Pinty-Verstraete) to the terrain corrected surface reflectance. The results, evaluated against ground measurements collected over several experimental sites on the Qinghai-Tibetan Plateau, document the advantage of integrating the sub-pixel topography effects in the land surface reflectance at 1km resolution to estimate the land surface albedo. The results obtained after using sub-pixel topographic correction are compared with the ones obtained after using pixel level topographic correction. The preliminary results imply that, in highly rugged terrain, the sub-pixel topography correction method gives more accurate results. The pixel level correction tends to overestimate surface albedo.
In southern South America the acquisition of high-quality Holocene paleoclimate data is a priority due to the paucity of complete, continuous and well dated records. Here we report preliminary results from a combined sedimentological and palynological study of an alluvial fan sequence and the laterally connected sedimentary deposits of the Vega de la Cueva profile at Agua Buena east of the Andes in central Argentina. The main geomorphological units of the area were identified and mapped based on satellite image analysis and multiple field surveys. The sedimentological and pollen results allowed us to reconstruct the development of some environments. The Agua Buena record corresponds to the distal facies of the Arroyo Bayo alluvial fan starting the aggradation process prior to ca. 4100 cal yr BP. The organic-rich levels found were formed during the development of wetlands (vegas) dominated by Cyperaceae, Juncaceae and Poaceae. These highly productive environments with almost permanent water saturation were important between 4100 and 2800 cal yr BP, indicating more stable conditions. After 2800 cal yr BP, the organic content was comparatively lower with increasing sedimentation rates that are indicative of higher fluvial discharges. This information is fundamental to interpret both the pollen and charcoal records of the area and to evaluate their representativeness and potential to reconstruct past local and/or regional vegetation.
Three-dimensional turbulent flow calculation of the flow in Francis
turbine in sandy river was conducted by using body-fitted coordinates,
tetrahedral grid system and SIMPLE algorithm based on the solid-liquid
two-phase flow equation of motion in Eulerian coordinate system. The
flow mechanism of sandy water in the turbine was analyzed through
numerical simulation of flow in the turbine in several different sand
water concentrations. In sandy water with various concentrations, the
erosion area of turbine are basically concentrated at the lateral wall
of the whole flow passage and the heads of guide vanes and blades.