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11.
Stanley A. Changnon 《Natural Hazards》2009,48(3):329-337
Property insurance data available for 1949–2006 were assessed to get definitive measures of hurricane losses in the U.S. Catastrophes,
events causing >$1 million in losses, were most frequent in the Southeast and South climate regions. Losses in these two regions
totaled $127 billion, 85% of the nation’s total losses. During the period 1949–2006 there were 79 hurricane catastrophes,
causing $150.6 billion in losses and averaging $2.6 billion per year. All aspects of these hurricanes showed increases in
post-1990 years. Sizes of loss areas averaged one state in 1949–1967, but grew to 3 states during 1990–2006. Seven of the
ten most damaging hurricanes came in 2004 (4) and 2005 (3). The number of hurricanes also peaked during 1984–2006, increasing
from an annual average of 1.2 during 1949–1983 to 2.1 per year. Losses were $49.3 billion in 1991–2006, 32% of the 58-year
total. Various reasons have been offered for such recent increases in hurricane losses including more hurricanes, more intense
tropical storms, increased societal vulnerability in storm-prone areas, and a change in climate due to global warming, although
this is debatable. 相似文献
12.
Prediction of coupled storm hydrodynamics and morphodynamics is essential for accurately designing coastal flood protection measures. A numerical simulation methodology was developed and implemented to evaluate and assess engineering design solutions for storm damage reduction along the south shore of Long Island, New York, USA. This simulation methodology was applied to compute bay water levels for two major coastal storms taking into account contributions from storm surge, waves, wind, and barrier island overwash and breaching. Simulation results for breaching and bay flooding compare well to historically documented barrier island morphological change and bay high water marks. 相似文献
13.
K. F. Cheung A. C. Phadke Y. Wei R. Rojas Y. J. -M. Douyere C. D. Martino S. H. Houston P. L. -F. Liu P. J. Lynett N. Dodd S. Liao E. Nakazaki 《Ocean Engineering》2003,30(11):1353-1386
This paper describes a model package that simulates coastal flooding resulting from storm surge and waves generated by tropical cyclones. The package consists of four component models implemented at three levels of nested geographic regions, namely, ocean, coastal, and nearshore. The operation is automated through a preprocessor that prepares the computational grids and input atmospheric conditions and manages the data transfer between components. The third generation spectral wave model WAM and a nonlinear long-wave model calculate respectively the wave conditions and storm surge over the ocean region. The simulation results define the water levels and boundary conditions for the model SWAN to transform the storm waves in coastal regions. The storm surge and local tides define the water level in each nearshore region, where a Boussinesq model uses the wave spectra output from SWAN to simulate the surf-zone processes and runup along the coastline. The package is applied to hindcast the coastal flooding caused by Hurricanes Iwa and Iniki, which hit the Hawaiian Island of Kauai in 1982 and 1992, respectively. The model results indicate good agreement with the storm-water levels and overwash debris lines recorded during and after the events, demonstrating the capability of the model package as a forecast tool for emergency management. 相似文献
14.
A numerical evaluation of the accuracy of the standard balance equations (BE) and the asymmetric balance equations (AB) in strong vortex applications is presented. Linearized equations for the evolution of disturbances on a symmetric hurricane-like vortex in a shallow-water model are used to compare forecasts using the AB and BE formulations with benchmark primitive equation forecasts. The validity of the BE and AB models is formally determined by the square of the Froude number, F2, and the square of the local Rossby number for disturbances with azimuthal wavenumber n, , respectively. The numerical experiments demonstrate that accurate results can be achieved with BE and AB in situations where F2 and , respectively, are not necessarily small. When the divergence of the asymmetric disturbance is not much smaller than its vorticity, and the azimuthal wavenumber of the disturbance is low, the AB system proves to be a useful alternative to BE. 相似文献
15.
A method is introduced for assessing the probabilities and intensities of tropical cyclones at landfall and applied to data
from the North Atlantic. First, a recently developed model for the basin-wide Monte-Carlo simulation of tropical cyclone tracks
is enhanced and transferred to the North Atlantic basin. Subsequently, a large number of synthetic tracks is generated by
means of an implementation of this model. This synthetic data is far more comprehensive than the available historical data,
while exhibiting the same basic characteristics. It, thus, creates a more sound basis for assessing landfall probabilities
than previously available, especially in areas with a low historical landfall frequency. 相似文献
16.
Ocean surges onto coastal lowlands caused by tropical and extra tropical storms, tsunamis, and sea level rise affect all coastal
lowlands and present a threat to drinking water resources of many coastal residents. In 2005, two such storms, Hurricanes
Katrina and Rita struck the Gulf Coast of the US. Since September 2005, water samples have been collected from water wells
impacted by the hurricanes’ storm surges along the north shore of Lake Pontchartrain in southeastern Louisiana. The private
and public water wells tested were submerged by 0.6–4.5 m of surging saltwater for several hours. The wells’ casing and/or
the associated plumbing were severely damaged. Water samples were collected to determine if storm surge water inundated the
well casing and, if so, its effect on water quality within the shallow aquifers of the Southern Hills Aquifer System. In addition,
the samples were used to determine if the impact on water quality may have long-term implication for public health. Laboratory
testing for several indicator parameters (Ca/Mg, Cl/Si, chloride, boron, specific conductance and bacteria) indicates that
surge water entered water wells’ casing and the screened aquifer. Analysis of the groundwater shows a decrease in the Ca/Mg
ratio right after the storm and then a return toward pre-Katrina values. Chloride concentrations were elevated right after
Katrina and Rita, and then decreased downward toward pre-Katrina values. From September 2005 to June 2006, the wells showed
improvement in all the saltwater intrusion indicators. 相似文献
17.
Siddhartha Mitra Joseph J. Lalicata Mead A. Allison Timothy M. Dellapenna 《Marine pollution bulletin》2009,58(6):851-857
To assess the extent to which Hurricanes Katrina and Rita affected polycyclic aromatic hydrocarbons (PAH) in the Gulf of Mexico (GOM), sediment cores were analyzed in late 2005 from: a shallow shelf, a deeper shelf, and a marsh station. Sediment geochronology, fabric, and geochemistry show that the 2005 storms deposited ∼10 cm of sediment to the surface of a core at 5-12A. Bulk carbon geochemistry and PAH isomers in this top layer suggest that the source of sediment to the top portion of core 5-12A was from a relatively more marine area. Particulate PAHs in the marsh core (04 M) appeared unaffected by the storms while sediments in the core from Station 5-1B (deeper shelf) were affected minimally (some possible storm-derived deposition). Substantial amounts of PAH-laden particles may have been displaced from the seabed in shallow areas of the water column in the GOM by these 2005 storms. 相似文献
18.
Modeling hurricane waves and storm surge using integrally-coupled,scalable computations 总被引：1，自引：0，他引：1
J.C. Dietrich M. Zijlema J.J. Westerink L.H. Holthuijsen C. Dawson R.A. Luettich Jr. R.E. Jensen J.M. Smith G.S. Stelling G.W. Stone 《Coastal Engineering》2011
The unstructured-mesh SWAN spectral wave model and the ADCIRC shallow-water circulation model have been integrated into a tightly-coupled SWAN + ADCIRC model. The model components are applied to an identical, unstructured mesh; share parallel computing infrastructure; and run sequentially in time. Wind speeds, water levels, currents and radiation stress gradients are vertex-based, and therefore can be passed through memory or cache to each model component. Parallel simulations based on domain decomposition utilize identical sub-meshes, and the communication is highly localized. Inter-model communication is intra-core, while intra-model communication is inter-core but is local and efficient because it is solely on adjacent sub-mesh edges. The resulting integrated SWAN + ADCIRC system is highly scalable and allows for localized increases in resolution without the complexity or cost of nested meshes or global interpolation between heterogeneous meshes. Hurricane waves and storm surge are validated for Hurricanes Katrina and Rita, demonstrating the importance of inclusion of the wave-circulation interactions, and efficient performance is demonstrated to 3062 computational cores. 相似文献
19.
20.
Paul A. Zandbergen 《Natural Hazards》2009,48(1):83-99
Exposure of counties in the continental United States to tropical storm and hurricane conditions was determined using the
historic record of storm tracks for the period 1851–2003. Two approaches were used to determine exposure: (1) cumulative number
of hits, with a hit occurring when the storm’s path crosses a county and (2) cumulative exposure factor, which describes how
much of the county has been exposed to tropical storm, hurricane, and intense hurricane-force winds. In both approaches the
top 10 counties in terms of cumulative exposure are in coastal Florida, North Carolina, and Louisiana. An explanatory model
was developed to describe the patterns in the documented exposure, which included distance to coast, latitude, longitude,
size, and shape of the counties. Multivariate linear regression confirmed that much of the spatial variability in exposure
to storm conditions can be explained with these simple parameters. 相似文献