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This study examines the effect of severe wind events on the mean and variance of housing price indices of six metropolitan statistical areas (MSA) that are vulnerable to hurricanes and/or tornadoes. The research focuses on three areas that experienced significant tornado activity (Fort Worth-Arlington, Nashville, and Oklahoma City) and three hurricane-prone areas (Corpus Christi, Miami, and Wilmington, NC). An econometric time series model that captures the housing market responses to severe windstorms is utilized. The model estimates changes in the local housing price index (HPI) as a function of several control variables as well as dichotomous variables that correspond to the tornadoes and hurricanes. As expected, the statistical findings indicate an immediate but short-lived decline in housing prices following a tornado or hurricane. Somewhat surprising is the result that the impact on the housing market is remarkably consistent whether the wind event was a hurricane or a tornado. Hurricanes and tornadoes are vastly different in terms of the point probabilities of a hit, the scope of the affected area and the lead time that supports last minute preparation to mitigate damage. It appears that the market response to destruction of real property does not distinguish between the types of wind event that produced the damage to the region. Results suggest that windstorms result in an immediate one-half to two percent reduction in total MSA housing value. This corresponds to a range of $34 million to $580 million in lost housing value. Estimates indicate some differences in how long market values continue to decline in the periods following the wind event; however, most of the decline occurs within four quarters after the windstorm. These differences can be attributed to the particular time series characteristics of the specific housing markets and their respective housing price indices. The market serves the purpose of integrating and normalizing the losses. In so doing the market provides a metric— a method for calibrating and comparing structural damage caused by different phenomenon.
Yongsheng WangEmail:
  相似文献   
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Surf zones, regions of breaking waves, are at the interface between the shore and coastal ocean. Surf zone hydrodynamics may affect delivery of phytoplankton subsidies to the intertidal zone. Over a month of daily sampling at an intermediate surf zone with bathymetric rip currents and a reflective surf zone, we measured surf zone hydrodynamics and compared concentrations of coastal phytoplankton taxa in the surf zones to concentrations offshore. At the intermediate surf zone, ~80% of the variability in the concentration of coastal phytoplankton taxa within the surf zone was explained by their variation offshore; however, concentrations were much higher and lower than those offshore in samples from a bathymetric rip current and over the adjacent shoal, respectively. Hydrodynamics at this intermediate surf zone did not hinder the delivery of coastal phytoplankton to the surf zone, but the bathymetric rip current system appeared to redistribute phytoplankton concentrating them within eddies. At the reflective shore, we sampled surf zones at a beach and two adjacent rocky intertidal sites. Concentrations of typical coastal phytoplankton taxa were usually an order of magnitude or more lower than those offshore, even when offshore samples were collected just 20 m beyond the breakers. The phytoplankton assemblages inside and outside the surf zone often appeared to be disconnected. Surf zone hydrodynamics at the steep, reflective shore coupled with low phytoplankton concentrations in near-surface water appeared to limit delivery of phytoplankton subsidies to the surf zone. Surf zone hydrodynamics may be a key factor in the alongshore variation in phytoplankton subsidies to coastal communities.  相似文献   
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VLBI observations of GNSS-satellites: from scheduling to analysis   总被引:1,自引:1,他引:0  
The possibility of observing satellites with the very long baseline interferometry (VLBI) technique has been discussed for several years in the geodetic community, with observations of either existing satellites of the global navigation satellite systems or of satellites dedicated to realise a space tie. Such observations were carried out using the Australian telescopes in Hobart and Ceduna which, for the first time, integrated all the necessary steps: planning the observations (automated scheduling), correlation of the data and the generation of a series of time delay observables suitable for a subsequent geodetic analysis. We report on the development of new and the adaptation of existing routines for observing and data processing, focusing on technology development. The aim was to use methods that are routinely used in geodetic VLBI. A series of test experiments of up to six hours duration was performed, allowing to improve the observations from session to session and revealing new problems still to be solved. The newly developed procedures and programs now enable more observations. Further development assumed, this bears the prospect of being directly applied to the observation of dedicated space-tie satellites.  相似文献   
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Many actions to reduce GHG emissions have wider impacts on health, the economy, and the environment, beyond their role in mitigating climate change. These ancillary impacts can be positive (co-benefits) or negative (conflicts). This article presents the first quantitative review of the wider impacts on health and the environment likely to arise from action to meet the UK's legally-binding carbon budgets. Impacts were assessed for climate measures directed at power generation, energy use in buildings, and industry, transport, and agriculture. The study considered a wide range of health and environmental impacts including air pollution, noise, the upstream impacts of fuel extraction, and the lifestyle benefits of active travel. It was not possible to quantify all impacts, but for those that were monetized the co-benefits of climate action (i.e. excluding climate benefits) significantly outweigh the negative impacts, with a net present value of more than £85 billion from 2008 to 2030. Substantial benefits arise from reduced congestion, pollution, noise, and road accidents as a result of avoided journeys. There is also a large health benefit as a result of increased exercise from walking and cycling instead of driving. Awareness of these benefits could strengthen the case for more ambitious climate mitigation action.

Policy relevance

This article demonstrates that actions to mitigate GHG emissions have significant wider benefits for health and the environment. Including these impacts in cost–benefit analysis would strengthen the case for the UK (and similar countries) to set ambitious emissions reduction targets. Understanding co-benefits and trade-offs will also improve coordination across policy areas and cut costs. In addition, co-benefits such as air quality improvements are often immediate and local, whereas climate benefits may occur on a longer timescale and mainly in a distant region, as well as being harder to demonstrate. Dissemination of the benefits, along with better anticipation of trade-offs, could therefore boost public support for climate action.  相似文献   

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Numerical modeling has emerged over the last several decades as a widely accepted tool for investigations in environmental sciences. In estuarine research, hydrodynamic and ecological models have moved along parallel tracks with regard to complexity, refinement, computational power, and incorporation of uncertainty. Coupled hydrodynamic-ecological models have been used to assess ecosystem processes and interactions, simulate future scenarios, and evaluate remedial actions in response to eutrophication, habitat loss, and freshwater diversion. The need to couple hydrodynamic and ecological models to address research and management questions is clear because dynamic feedbacks between biotic and physical processes are critical interactions within ecosystems. In this review, we present historical and modern perspectives on estuarine hydrodynamic and ecological modeling, consider model limitations, and address aspects of model linkage, skill assessment, and complexity. We discuss the balance between spatial and temporal resolution and present examples using different spatiotemporal scales. Finally, we recommend future lines of inquiry, approaches to balance complexity and uncertainty, and model transparency and utility. It is idealistic to think we can pursue a “theory of everything” for estuarine models, but recent advances suggest that models for both scientific investigations and management applications will continue to improve in terms of realism, precision, and accuracy.  相似文献   
100.
Over the past two decades, there has been a resurgence of interest into place‐based influences on health. Researchers have identified that various characteristics of neighbourhoods exert an influence on the health outcomes and behaviours of local residents. Understanding the processes linking places to health provides considerable potential for a range of policy interventions. We review the New Zealand‐based neighbourhoods and health research. Consideration is given to the types of neighbourhood characteristics, as well the range of health outcomes that have been studied. Finally, we suggest some priorities for further research into the mechanisms underpinning neighbourhood influences on health in New Zealand.  相似文献   
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