Database of glacial lake outburst floods (GLOFs)–IPL project No. 179     

Vít Vilímek  Adam Emmer  Christian Huggel  Yvonne Schaub  Sara Würmli 《Landslides》2014,11(1):161-165

This article summarises activities and preliminary results of the International Programme on Landslides Project no. 179 “Database of glacial lake outburst floods (GLOFs)”. This project is planned for 3 years (2013–2015); the main objectives of the first year are (1) to create an online database and (2) to select collaborating partners. A survey of existing and relevant documents, information and organisations has been initiated along with the creation of a website (www.glofs-database.org) and the establishment of international collaboration. The first preliminary results show regional differences in various attributes of GLOF events (e.g. triggers, chronological distribution). These differences should be taken into consideration in regionally focused methods of hazard assessment, mitigation and consequently risk management.  相似文献   

Assessing the immediate and short-term impact of flooding on residential property participant behaviour   总被引：1，自引：1，他引：0  

Chris Eves  Sara Wilkinson 《Natural Hazards》2014,71(3):1519-1536

The past decade has seen an increase in the number of significant natural disasters that have caused considerable loss of life as well as damage to all property markets in the affected areas. In many cases, these natural disasters have not only caused significant property damage, but in numerous cases, have resulted in the total destruction of the property in the location. With these disasters attracting considerable media attention, the public are more aware of where these affected property markets are, as well as the overall damage to properties that have been damaged or destroyed. This heightened level of awareness has to have an impact on the participants in the property market, whether a developer, vendor seller or investor. To assess this issue, a residential property market that has been affected by a significant natural disaster over the past 2 years has been analysed to determine the overall impact of the disaster on buyer, renter and vendor behaviour, as well as prices in these residential markets. This paper is based on data from the Brisbane flood in January 2011. This natural disaster resulted in loss of life and partial and total devastation of considerable residential property sectors. Data for the research have been based on the residential sales and rental listings for each week of the study period to determine the level of activity in the specific property sectors, and these are also compared to the median house prices for the various suburbs for the same period based on suburbs being either flood affected or flood free. As there are 48 suburbs included in the study, it has been possible to group these suburbs on a socio-economic basis to determine possible differences due to location and value. Data were accessed from realestate.com.au, a free real estate site that provides details of current rental and sales listings on a suburb basis, RP Data a commercial property sales database and the Australian Bureau of Statistics. The paper found that sales listings fell immediately after the flood in the affected areas, but there was no corresponding fall or increase in sales listings in the flood-free suburbs. There was a significant decrease in the number of rental listings follow the flood as affected parties sought alternate accommodation. The greatest fall in rental listings was in areas close to the flood-affected suburbs indicating the desire to be close to the flooded property during the repair period.  相似文献   

Probabilistic seismic hazard analysis at a strategic site in the Bay of Bengal   总被引：1，自引：1，他引：0  

Sara Cristina Teresa Trianni  Carlo Giovanni Lai  Erio Pasqualini 《Natural Hazards》2014,74(3):1683-1705

Probabilistic seismic hazard analysis (PSHA) along the route of an offshore pipeline for the transport of oil in the Bay of Bengal has been performed, in order to set up design parameters and identify possible geohazards. The complexity of geological and seismotectonic setting of the region where the pipeline is planned to be installed is the result of the interaction of the Indian, Eurasian and Burmese tectonic plates. In order to properly account for the intricate way by which these plates interact, a large area extending 450 km from the pipeline route has been considered for the compilation of a comprehensive earthquake catalogue, spanning the period 1663–2012 AD. Differently from earlier PSHA analyses conducted in the region based on assuming two-dimensional polygons as seismogenic provinces, this study adopted a seismotectonic source model which also includes for the first time a linear tectonic lineament representing the northward extension of the Sunda mega thrust, responsible for the large Sumatra–Andaman earthquake of 26 December 2004. Hazard computations have been performed over a grid of sites spaced 0.045° covering a rectangular area which contains the pipeline. Epistemic uncertainty in the hazard computations has been taken into account by a logic tree framework, incorporating different seismotectonic source models, maximum cut-off magnitude and ground-motion prediction equations. Horizontal median uniform hazard spectra and median uniform hazard spectra plus and minus one sigma on stiff ground have been calculated at the selected sites for different return periods. Peak ground acceleration with 10 % probability of exceedance in 50 years has been compared with values from previous hazard studies available for Bangladesh.  相似文献   

Does martian soil release reactive halogens to the atmosphere?     

Suniti Karunatillake  Yu-Yan Sara Zhao  Scott M. McLennan  J.R. Skok  Nicole E. Button 《Icarus》2013

Detailed statistical examination of Cl, Br, and S distributions, in martian soil profiles at Gusev Crater and Meridiani Planum, indicates decreasing Br abundance and weakening Br–S association towards the surface. All three elements decrease towards the surface in the order Cl < S < Br. Furthermore, Br variability decouples from potential cations such as Mg at the surface relative to the subsurface. These observations support a relative loss of surficial Br compared to S and Cl, all highly mobile elements in aqueous environments. We propose that Br may have converted preferentially to gas phases (e.g., BrO), driven either by UV photolysis or by chemical oxidants. Such volatilization pathways may in turn impart a global signature on Mars by acting as controls on oxidants such as ozone and perchlorates. S/Cl mass ratios vary with depth (∼4–5 in the subsurface; 1.8–3.6 on the surface) as well, with a strong correlation of S and Cl near the surface but more variable at depth, consistent with differential vertical mobility, but not volatilization of Cl. Elevated S/Cl in subsurface soil also suggests that the ratio may be higher in bulk soil – a key repository of martian geologic and climatic records – than previously thought.  相似文献   

Mass Flux Analysis of Abiotic Tetrachloroethene Dense Nonaqueous Phase Liquid Pool Dissolution in a Heterogeneous Flow Environment     

Sara M. Klemm  Eric A. Seagren  Jennifer G. Becker  Alex S. Mayer 《Ground Water Monitoring & Remediation》2021,41(4):33-48

Porous aquifer materials are often characterized by layered heterogeneities that influence groundwater flow and present complexities in contaminant transport modeling. Such flow variations also have the potential to impact the dissolution flux from dense nonaqueous phase liquid (DNAPL) pools. This study examined how these heterogeneous flow conditions affected the dissolution of a tetrachloroethene (PCE) pool in a two-dimensional intermediate-scale flow cell containing coarse sand. A steady-state mass-balance approach was used to calculate the PCE dissolution rate at three different flow rates. As expected, aqueous PCE concentrations increased along the length of the PCE pool and higher flow rates decreased the aqueous PCE concentration in the effluent. Nonreactive tracer studies at two flow rates confirmed the presence of a vertical flow gradient, with the most rapid velocity located at the bottom of the tank. These results suggest that flow focusing occurred near the DNAPL pool. Effluent PCE concentrations and pool dissolution flux rates were compared to model predictions assuming local equilibrium (LE) conditions at the DNAPL pool/aqueous phase interface and a uniform distribution of flow. The LE model did not describe the data well, even over a wide range of PCE solubility and macroscopic transverse dispersivity values. Model predictions assuming nonequilibrium mass-transfer-limited conditions and accounting for vertical flow gradients, however, resulted in a better fit to the data. These results have important implications for evaluating DNAPL pool dissolution in the field where subsurface heterogeneities are likely to be present.  相似文献   

Observations and implications of damage from the magnitude Mw 6.3 Christchurch, New Zealand earthquake of 22 February 2011   总被引：1，自引：1，他引：0  

Sean Wilkinson  Damian Grant  Elizabeth Williams  Sara Paganoni  Stuart Fraser  David Boon  Anna Mason  Matthew Free 《Bulletin of Earthquake Engineering》2013,11(1):107-140

This paper describes the observations made by a reconnaissance team following the 22nd February 2011, M_w 6.3, Christchurch, New Zealand earthquake (GNS Science, 2011). The team comprised of members of the UK based Earthquake Engineering Field Investigation Team who spent 5 days collecting observations on damage resulting from the earthquake. Although the magnitude of this earthquake was not particularly high (M_w 6.3), the shallow focus and close proximity resulted in locally very high ground motions, widespread damage and 182 fatalities. The earthquake is also particularly notable for the widespread liquefaction it caused, landslides and rockfalls in the hills south of Christchurch, and the significant damage suffered by unreinforced masonry and historic structures. Over wide areas of central Christchurch, recorded accelerations were in excess of those required by the current New Zealand seismic loadings standard (NZS1170.5:2004: Standards New Zealand 2004) and therefore the earthquake presented a valuable opportunity to assess performance of modern buildings under code-level ground acceleration.  相似文献   

Nitrogen Removal in Vegetated and Unvegetated Drainage Ditches Impacted by Diffuse and Point Sources of Pollution     

Enrica Pierobon  Giuseppe Castaldelli  Sara Mantovani  Fabio Vincenzi  Elisa Anna Fano 《洁净——土壤、空气、水》2013,41(1):24-31

Secondary drainage canals have the potential to effectively mitigate excess nitrogen loads from diffuse and point sources. In vegetated (Phragmites australis and Typha latifolia) and in unvegetated canals subjected to diffuse and point pollution, nitrogen removal was evaluated by means of simple in–out mass balance and potential uptake by macrophytes was estimated from biomass data. Results suggest an elevated control of nitrogen in vegetated ditches receiving point source of pollution (average abatement of 50% of the total N load per linear km), whereas removal processes are much less effective in unvegetated ditches. The comparison between net abatement and plant uptake, highlights the presence of other unaccounted for processes responsible for a relevant percentage of total N removal. Overall, results from this study suggest the importance of actions aiming at the appropriate management of emergent vegetation, in order to improve its direct and indirect metabolic functions and maximize nitrogen removal in impacted watersheds.  相似文献   

Who has long commutes to low-wage jobs? Gender,race, and access to work in the New York region     

Sara McLafferty  Valerie Preston 《Urban geography》2013,34(9):1270-1290

Geographies of home and work have changed as public investment has favored central and distant suburban locations and as income inequality has increased. These changes result in shifting geographies of advantage that (dis)benefit gender and racial/ethnic groups unevenly. We examine commuting differentials by gender and race/ethnicity based on combinations of wages and commute times using data for the New York region.We find that Black, Asian, and Hispanic women and men are concentrated in jobs that have long commutes and low-wages, and Black and Hispanic workers’ concentrations increased from 2000–2010.Although Asian men and women remain overrepresented in that category, their share decreased in the 2000's.The urban core has become a region of heightened advantage, as White men, and an increasing share of White women, commute short times to well-paid jobs. Disadvantage has expanded for Black and Latina women whose long commutes are not compensated by well-paid employment.  相似文献   

Late-Stage Breast Cancer Diagnosis and Health Care Access in Illinois∗     

Fahui Wang  Sara McLafferty  Veronica Escamilla  Lan Luo 《The Professional geographer》2013,65(1):54-69

The variations of breast cancer mortality rates from place to place reflect both underlying differences in breast cancer prevalence and differences in diagnosis and treatment that affect the risk of death. This article examines the role of access to health care in explaining the variation of late-stage diagnosis of breast cancer. We use cancer registry data for the state of Illinois by zip code to investigate spatial variation in late diagnosis. Geographic information systems and spatial analysis methods are used to create detailed measures of spatial access to health care such as convenience of visiting primary care physicians and travel time from the nearest mammography facility. The effects of spatial access, in combination with the influences of socioeconomic factors, on late-stage breast cancer diagnosis are assessed using statistical methods. The results suggest that for breast cancer, poor geographical access to primary health care significantly increases the risk of late diagnosis for persons living outside the city of Chicago. Disadvantaged population groups including those with low income and racial and ethnic minorities tend to experience high rates of late diagnosis. In Illinois, poor spatial access to primary health care is more strongly associated with late diagnosis than is spatial access to mammography. This suggests the importance of primary care physicians as gatekeepers in early breast cancer detection.  相似文献   

Recent Publications     

Sara Macdonald  Roger Keil 《The Professional geographer》2013,65(1):125-145

The government of Ontario, Canada, has passed legislation to protect large parts of the southern portions of the province from most development. An extensive plan for a Greenbelt that surrounds the Greater Toronto Area and other regional growth centers was introduced. This article looks at the new policy as a spatial strategy that shifts the scales of environmental and growth management policy in Ontario. The legislation also sets the framework for a state spatial project; that is, a set of changes in how the regional state internally operates. The current Greenbelt legislation is a new step in a longer term development by which governments in Ontario have attempted to regulate the relationships between cities and regions, town and hinterland. Overlapping strongly with what is usually called the Toronto bioregion between the Niagara Escarpment, Oak Ridges Moraine, and Lake Ontario, the Greenbelt reorganizes space in southern Ontario in ways that would further ecosystem policies and practices in the area. Theoretically guided by newer debates on rescaling and regionalism, and based on close reading of the planning and policy documents on the Greenbelt as well as a series of expert interviews, we argue that the current Greenbelt legislation is an act of up-scaling traditional urban-regional regulation in southern Ontario, which we shall call extended metropolitanization. Such rescaling recasts traditional political conflicts in new terms. We conclude that extended metropolitanization in southern Ontario has been a process that has brought nature, the state, and governance together into a new regional sustainability fix.  相似文献