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1.
It is well recognized that sea surface temperature (SST) plays a dominant role in the formation and intensification of tropical
cyclones. A number of observational/empirical studies were conducted at different basins to investigate the influence of SST
on the intensification of tropical cyclones and in turn, modification in SST by the cyclone itself. Although a few modeling
studies confirmed the sensitivity of model simulation/forecast to SST, it is not well quantified, particularly for Bay of
Bengal cyclones. The present study is designed to quantify the sensitivity of SST on mesoscale simulation of an explosively
deepening storm over the Bay of Bengal, i.e., Orissa super cyclone (1999). Three numerical experiments are conducted with
climatological SST, NCEP (National Center for Environmental Prediction) skin temperature as SST, and observed SST (satellite
derived) toward 5-day simulation of the storm using mesoscale model MM5. At model initial state, NCEP skin temperature and
observed SST over the Bay of Bengal are 1–2°C warmer than climatological SST, but cooler by nearly 1°C along the coastline.
Observed SST shows a number of warm patches in the Bay of Bengal compared with NCEP skin temperature. The simulation results
indicate that the sea surface temperature has a significant impact on model-simulated track and intensity of the cyclonic
storm. The track and intensity of the storm is better simulated with the use of satellite-observed SST. 相似文献
2.
Asbury H. Sallenger Hilary F. Stockdon Laura Fauver Mark Hansen David Thompson C. Wayne Wright Jeff Lillycrop 《Estuaries and Coasts》2006,29(6):880-888
Four hurricanes battered the state of Florida during 2004, the most affecting any state since Texas endured four in 1884.
Each of the storms changed the coast differently. Average shoreline change within the right front quadrant of hurricane force
winds varied from 1 m of shoreline advance to 20 m of retreat, whereas average sand volume change varied from 11 to 66 m3 m−1 of net loss (erosion). These changes did not scale simply with hurricane intensity as described by the Saffir-Simpson Hurricane
Scale. The strongest storm of the season, category 4 Hurricane Charley, had the least shoreline retreat. This was likely because
of other factors like the storm's rapid forward speed and small size that generated a lower storm surge than expected. Two
of the storms, Hurricanes Frances and Jeanne, affected nearly the same area on the Florida east coast just 3 wk apart. The
first storm, Frances, although weaker than the second, caused greater shoreline retreat and sand volume erosion. As a consequence,
Hurricane Frances may have stripped away protective beach and exposed dunes to direct wave attack during Jeanne, although
there was significant dune erosion during both storms. The maximum shoreline change for all four hurricanes occurred during
Ivan on the coasts of eastern Alabama and the Florida Panhandle. The net volume change across a barrier island within the
Ivan impact zone approached zero because of massive overwash that approximately balanced erosion of the beach. These data
from the 2004 hurricane season will prove useful in developing new ways to scale and predict coastal-change effects during
hurricanes. 相似文献
3.
The rapid intensification of Hurricane Charley (2004) near landfall is studied using the fifth-generation Pennsylvania State
University/National Center for Atmospheric Research (PSU/NCAR) Mesoscale Model (MM5) and its adjoint system for both vortex
initialization and forecasts. A significant improvement in both track and intensity forecasts is achieved after an ill-defined
storm vortex, derived from large-scale analysis, in the initial condition is replaced by the vortex generated by a four-dimensional
data variational (4D-Var) hurricane initialization scheme. Results from numerical experiments suggest that both the inclusion
of the upper-level trough and the use of high horizontal resolution (6 km) are important for numerical simulations to capture
the observed rapid intensification as well as the size reduction during the rapid intensification of Hurricane Charley. The
approach of the upper-level trough significantly enhanced the upper-level divergence and vertical motion within simulated
hurricanes. Small-scale features that are not resolvable at 18 km resolution are important to the rapid intensification and
shrinking of Hurricane Charley (2004). Numerical results from this study further confirm that the theoretical relationship
between the intensification and shrinking of tropical cyclones based on the angular momentum conservation and the cyclostrophic
approximation can be applied to the azimuthal mean flows. 相似文献
4.
We present here the first high-resolution pollen record of vegetation response to interactions of hurricane and fire disturbances over the past 1200 yr from a small lake in Alabama on the Gulf of Mexico coast. The paleotempestological record inferred from the overwash sand layers suggests that the Alabama coast was directly struck by Saffir-Simpson category 4 or 5 hurricanes twice during the last 1200 yr, around 1170 and 860 cal yr BP, suggesting an annual landfall probability of 0.17% for these intense hurricanes. The charcoal data suggest that intense fires occurred after each of these hurricanes. The pollen data suggest that populations of halophytic plants (Chenopodiaceae) and heliophytic shrubs (Myrica) expanded after the hurricane strikes, probably due to saltwater intrusion into the marshes and soil salinization caused by overwash processes. Populations of pines (Pinus sp.) decreased significantly after each intense hurricane and the ensuing intense fire, suggesting that repeated hurricane-fire interactions resulted in high tree mortality and probably impeded recruitment and recovery. Our data support the hypothesis that the likelihood and intensity of fire increased significantly after a major hurricane, producing responses by vegetation that are more complex and unpredictable than if the disturbance agents were acting singly and independently. 相似文献
5.
Widespread inland floods for 20th century North Carolina, USA were defined from stream flow records as events where flow was more than one standard deviation above the mean annual peak for at least two contiguous drainage basins simultaneously. Thirty-one events were identified. One snowmelt flood was detected. For the others, synoptic causes were identified from precipitation and circulation data. Eight events were directly related to hurricanes. Each required a precursor storm, often another hurricane, to provide sufficient precipitation to overcome the dry soils and low stream flows of the autumnal hurricane season. The decadal frequencies of these floods were poorly correlated with the total number of hurricanes, with no hurricane floods between 1955 and 1999 despite frequent hurricanes. Further, most events involved slow-moving decaying systems, not intense ones. An increase in hurricane intensity, often suggested as a consequence of climate change, may lead to fewer floods. The other floods were produced by either extra-tropical storms or squall lines, and precursor systems were also needed. These floods were common in the first and last three decades of the century, virtually absent in the middle four. This corresponded to a small dip in the total number of cyclones, and to periods of rising temperature statewide. This suggests a future increase in North Carolina floods as global temperatures increase. However, the synoptic causes of the relationship are not clear, and detailed quantitative analyses of recent events are required. 相似文献
6.
7.
超强台风Saomai(0608)加强成因分析及 海温影响的数值试验研究* 总被引：4，自引：0，他引：4
以严重影响我国的2006年8号超强台风Saomai为研究对象,首先从大尺度环流特征和物理量场对其登陆前强度不断加强成因作诊断分析,指出台风加强与副高的加强和南落、低空持续加强的水汽输送、高空流出气流的强辐散、台风移向垂直切变小值区和暖洋面密切相关。然后,利用中尺度数值模式MM5分析了海温高低对台风强度变化的影响,试验结果表明台风强度对海温十分敏感,海温改变可以引起台风强度的迅速变化,海温降低2℃将使台风最终减弱19hPa。边界层通量的分析表明,海温变化对台风强度的影响中潜热通量的作用是主要的,而感热输送的作用较小。就海温变化是否引起诸多台风强度影响因子分析发现,高海温使台风区域低空气旋式环流和高层辐散流出加强,导致低空更多的水汽向该区辐合,暖海面上空潮湿空气的辐合上升释放大量的凝结潜热为台风的发展加强提供了更多的水汽和能量。对比试验还表明,正位涡向下输送预示着台风将快速加强。另外,本次试验中海温变化对台风移动路径影响不明显, 因而对环境风的垂直切变影响较小。 相似文献
8.
A surge response function approach to coastal hazard assessment. Part 2: Quantification of spatial attributes of response functions 总被引：2，自引：2，他引：0
In response to the 2004 and 2005 hurricane seasons, surge risk assessment approaches have been re-evaluated to develop more
rapid, reliable methods for predicting the risk associated with extreme hurricanes. Here, the development of dimensionless
surge response functions relating surge to hurricane meteorological parameters is presented. Such response functions present
an opportunity to maximize surge data usage and to improve statistical estimates of surge probability by providing a means
for defining continuous probability density functions. A numerical modeling investigation was carried out for the Texas, USA
coastline to develop physical scaling laws relating storm surge response with hurricane parameters including storm size, intensity,
and track. It will be shown that these scaling laws successfully estimate the surge response at any arbitrary location for
any arbitrary storm track within the study region. Such a prediction methodology has the potential to decrease numerical computation
requirements by 75% for hurricane risk assessment studies. 相似文献
9.
Jorge Villegas Corene Matyas Sivaramakrishnan Srinivasan Ignatius Cahyanto Brijesh Thapa Lori Pennington-Gray 《Natural Hazards》2013,66(1):97-116
Tourists are particularly vulnerable to natural disasters such as hurricanes since they might be less informed and prepared than residents of disaster-prone areas. Thus, understanding how the traits of a tropical cyclone as well as specific characteristics of tourists influence affective and cognitive responses to a hurricane warning message is a critical component in disaster planning. Using scenarios that presented tropical cyclones with different relevant characteristics (such as category at landfall), tourists’ knowledge, experience with hurricanes, trip traits, and the location of the survey (coastal or inland), this study contributes to the literature on sociological issues related to natural disasters. The findings suggest that risk perceptions and fear are influenced differently by the traits of the hurricanes and tourists’ knowledge and experience. Risk is strongly influenced by the projected category of the hurricane at landfall, while fear is not as sensitive to this extremely relevant trait of cyclones. The results also suggest that the influence of risk and fear on evacuation likelihood is strong and positive. This study shows the value of studying cognitive and affective responses to uncertain events. 相似文献
10.
Risk perception and evacuation decisions of Florida tourists under hurricane threats: a stated preference analysis 总被引：2，自引：2，他引：0
Corene Matyas Sivaramakrishnan Srinivasan Ignatius Cahyanto Brijesh Thapa Lori Pennington-Gray Jorge Villegas 《Natural Hazards》2011,59(2):871-890
Though most hurricane evacuation studies have focused on residents, tourists are also a vulnerable population. To assess their
perceptions of risk and evacuation likelihood under different hurricane conditions, we surveyed 448 tourists visiting central
Florida. Respondents viewed four maps emulating track forecast cones produced by the National Hurricane Center and text information
featuring variations of storm intensity, coast of landfall, centerline position relative to the survey site, time until landfall,
and event duration. We performed chi-square tests to determine which hurricane conditions, and aspects of tourists such as
their demographics and previous hurricane experience, most likely influenced their ratings of risk and evacuation likelihood
for respondents located on Pinellas County beaches or inland near Orlando, FL. Highly rated scenarios featured a Category
4 hurricane making landfall along the Gulf Coast with the centerline passing over the sampling site. Overall, tourists that
indicated the highest risk and evacuation ratings were not previously affected by a hurricane, had a trip duration of less
than 6 days, and had checked for the possibility of a hurricane strike before departure. However, results for other tourist
attributes differed between tourists in coastal and inland locations. We found that although somewhat knowledgeable about
hurricanes, tourists misinterpreted the track forecast cone and hurricane conditions, which led to a lower perception of risk
and subsequent likelihood to evacuate. Tourists, particularly those from outside of Florida, need to be better educated about
the risks they face from hurricanes that make landfall. 相似文献
11.
The impact of realistic representation of sea surface temperature (SST) on the numerical simulation of track and intensity
of tropical cyclones formed over the north Indian Ocean is studied using the Weather Research and Forecast (WRF) model. We
have selected two intense tropical cyclones formed over the Bay of Bengal for studying the SST impact. Two different sets
of SSTs were used in this study: one from TRMM Microwave Imager (TMI) satellite and other is the weekly averaged Reynold’s
SST analysis from National Center for Environmental Prediction (NCEP). WRF simulations were conducted using the Reynold’s
and TMI SST as model boundary condition for the two cyclone cases selected. The TMI SST which has a better temporal and spatial
resolution showed sharper gradient when compared to the Reynold’s SST. The use of TMI SST improved the WRF cyclone intensity
prediction when compared to that using Reynold’s SST for both the cases studied. The improvements in intensity were mainly
due to the improved prediction of surface latent and sensible heat fluxes. The use of TMI SST in place of Reynold’s SST improved
cyclone track prediction for Orissa super cyclone but slightly degraded track prediction for cyclone Mala. The present modeling
study supports the well established notion that the horizontal SST gradient is one of the major driving forces for the intensification
and movement of tropical cyclones over the Indian Ocean. 相似文献
12.
Tariq Masood Ali Khan Dewan Abdul Quadir Tad S. Murty Majajul Alam Sarker 《Natural Hazards》2004,31(2):549-560
The sea surface temperature (SST) variations play a veryimportant role in the genesis and maintenance of meteorological and oceanographic processessuch as monsoon depressions and subsequent floods, large-scale sea level fluctuationsand genesis of tropical cyclones. Many low lying coastal regions of South Asia are adjacentto river deltas and have large population. The dense population, poor economy and severalother socio-economic factors make these areas most vulnerable to the impact of climate change.Variability of sea surface temperature (SST) is importantas the duration and intensity of SST provide the basis for studies related to climatic changescenario. In this study an attempt has been made to estimate the recent SST trends in the coastalwaters of some cities, which lie on the Arabian Sea and Bay of Bengal. The annual andinterannual variability has also been studied. The SST variations have then been linkedwith the El Nino and La Nina events.The NOAA-NASA Pathfinder Advanced Very High Resolution Radiometer (AVHRR) SST fields from 1985-1998, created in the Jet Propulsion Laboratory(JPL), USA are used in this study. Here the quality of data is an important factor toobtain reliable estimates of Sea Surface Temperature (SST) trends and other related parameters.However, this is not possible with the conventional type data, due to low quality as wellas sparse data in the region. Though the satellite based SST climatologies have shorterobservation lengths, they can provide reliable estimates of recent SST variability overa large oceanic areas with sparse or no data.Increasing trend of SST is observed throughout all theseasons in the northern Arabian Sea extending from Oman to Karachi and Mumbai and furthersouth to Salalah and Colombo. However, in coastal islands stations further south ofIndia such as at Colombo the increment is not significant. Though the increasing trend in SSTduring winter is not significant, nevertheless it shows the increasing influence of coldspells on this Island. An interesting situation has been observed in the Bay of Bengal. On anaverage, increasing trends in the annual SST were observed in Visakhaputnam. But at thestations located in the northeastern part of Bay of Bengal, namely Hiron Point and Cox'sBazar reverse conditions are observed. In the Southern Bay of Bengal variations in SST isnot significant which reflects in the SST analysis of Chennai and Port Blair stations. Locationof these stations at lower latitudes (near by equator) probably is the reason for this insignificantchange. It has been found that the interannual mode of SST variations dominate the linear SSTtrends which is characterized by the El Nino Southern Oscillations (ENSO) scale cycle. 相似文献
13.
Improvements in hurricane forecasts allowing for more timely evacuations from storm-surge zones are credited with reducing
lethality of US landfalling hurricanes. The deadly reach of a hurricane, however, is not limited to storm-surge zones. About
80% of direct US hurricane fatalities since 1970 occurred outside of landfall counties, with most of these fatalities caused
by inland flooding. We construct a geographic information system database combining the location and cause of fatalities,
estimated wind speeds, and rainfall amounts for the entire track of the storm for landfalling US hurricanes between 1970 and
2007. We analyze the determinants of total fatalities and deaths due to freshwater drowning and wind. Inclusion of inland
fatalities results in no downward trend in lethality over the period, in contrast to prior research. Local storm conditions
significantly affect lethality, as one-inch and one-knot increases in rainfall and wind increase total fatalities by 28 and
4%. Rainfall significantly increases freshwater-drowning deaths and is insignificant for wind deaths, while the opposite relation
holds for wind speed. While coastal counties do not exhibit a significantly higher amount of lethality risk versus inland
counties for total or wind-driven fatalities, freshwater-drowning fatalities occur most frequently in inland counties along
the center of the storm path and its outer county tiers as we have defined them. 相似文献
14.
How hurricane attributes determine the extent of environmental effects: Multiple hurricanes and different coastal systems 总被引：2，自引：0，他引：2
The most recent spate of hurricanes to strike the United States and Caribbean (1989 to the present) has occurred when many
of the affected areas had long-term water quality and biological data collection efforts ongoing, as well as special follow-up
studies. These data have allowed researchers to obtain a much clearer picture of how individual characteristics of hurricanes
interact with human land use to lead to various types and degrees of environmental effects. Common deleterious water quality
effects associated with hurricanes include excessive nutrient loading, algal blooms, elevated biochemical oxygen demand and
subsequent hypoxia and anoxia, fish and invertebrate kills, aquatic animal displacements, large scale releases of chemical
pollutants and debris from damaged human structures, exacerbated spread of exotic species and pathogens, and pollution of
water with fecal microbial pathogens. These and other effects may or may not occur, or occur to varying degrees, depending
upon individual hurricane characteristics including category, point of landfall, wind speed, amount of rainfall, and path
after landfall. Landfall in a populous area, a post-landfall trajectory upriver toward a headwater region, passage along a
floodplain containing pollution sources (such as wastewater treatment plants, concentrated animal feeding operations, and
septic systems), and intensity sufficient to damage power generation will all lead to increased environmental damage. We suggest
a number of recommendations for post-hurricane water sampling parameters and techniques, and provide several management-oriented
recommendations for better coastal and floodplain land use aimed at lessening the water quality effects of hurricanes. 相似文献
15.
Based on complex analysis of the results of instrumental observations during strong atmospheric disturbances, it is shown that hurricanes and squalls are accompanied not only by high wind velocities, but also by high-amplitude microbaric variations, variations in amplitudes of the microseismic background, and the vertical component of the electric field. It is established that 1–4 hours before the onset, squalls and hurricanes are characterized by increased amplitudes of microbaric variations in the range of periods of 2–6 min, as well as by low-frequency variations in the electric field and variations in the microseismic background, which together with the meteorological parameters can be considered as a complex prognostic criterion of an impending hurricane (squall). 相似文献
16.
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
17.
Social vulnerability index for coastal communities at risk to hurricane hazard and a changing climate 总被引：3，自引：1，他引：2
This paper presents the development of the Coastal Community Social Vulnerability Index (CCSVI) in order to quantify the social
vulnerability of hurricane-prone areas under various scenarios of climate change. The 2004–2005 Atlantic hurricane seasons
is estimated to have caused 150 billion dollars in damages, and in recent years, the annual hurricane damage in the United States is estimated at around150 billion dollars in damages, and in recent years, the annual hurricane damage in the United
States is estimated at around 6 billion. Hurricane intensity or/and frequency may change due to the increase in sea surface
temperature as a result of climate change. Climate change is also predicted to cause a rise in sea levels, potentially resulting
in higher storm surges. The CCSVI combines the intensity of hurricanes and hurricane-induced surge to create a comprehensive
index that considers the effects of a changing climate. The main contributing factors of social vulnerability (such as race,
age, gender, and socioeconomic status) in hurricane-prone areas are identified through a principal components analysis. The
impact of social characteristics on the potential hurricane damage under various scenarios of climate change are evaluated
using Miami-Dade County, Florida, as a case study location. This study finds that climate change may have a significant impact
on the CCSVI. 相似文献
18.
Natural disasters, like hurricanes, can damage properties and critical infrastructure systems, degrade economic productivity, and in extreme situations can cause injuries and mortalities. This paper focuses particularly on workforce disruptions in the aftermath of hurricanes. We extend the dynamic inoperability input?Coutput model (DIIM) by formulating a workforce recovery model to identify critical industry sectors. A decision analysis tool is utilized by integrating the economic loss and inoperability metrics to study the interdependent effects of various hurricane intensities on Virginia??s workforce sectors. The extended DIIM and available workforce survey data are incorporated in the decision support tool to simulate various hurricane scenarios. For a low-intensity hurricane scenario, the simulated total economic loss to Virginia??s industry sectors due to workforce absenteeism is around $410 million. Examples of critical sectors that suffer the highest losses for this scenario include: (1) miscellaneous professional, scientific, and technical services; (2) federal general government; (3) state and local government enterprises; (4) construction; and (5) administrative and support services. This paper also explores the inoperability metric, which describes the proportion in which a sector capacity is disrupted. The inoperability metric reveals a different ranking of critical sectors, such as: (1) social assistance; (2) hospitals and nursing and residential care facilities; (3) educational services; (4) federal government enterprises; and (5) federal general government. Results of the study will help identify the critical workforce sectors and can ultimately provide insights into formulating preparedness decisions to expedite disaster recovery. The model was applied to the state of Virginia but can be generalized to other regions and other disaster scenarios. 相似文献
19.
Daniel Solís Larry Perruso Julio del Corral Brent Stoffle David Letson 《Natural Hazards》2013,66(2):271-289
A stochastic production frontier was used to measure the initial (i.e., bi-weekly) economic effects of hurricanes on commercial grouper (Serranidae) production in the Exclusive Economic Zone of the United States Gulf of Mexico from 2005 to 2009. We estimated the economic effects of productivity losses associated with specific hurricanes on the commercial grouper fleet. We also calculated the economic effects due to productivity losses during an entire hurricane season at the regional level. The empirical model controls for input levels as well as other factors affecting production to isolate the initial economic effect caused by hurricanes from other non-weather-related factors. The empirical results revealed that hurricanes striking the Gulf of Mexico coastline from 2005 to 2009 had a negative effect on the production of the commercial grouper fleet. The results also demonstrated the relative importance of inputs and regulations on fish production. 相似文献
20.
Stephen Vermette 《Natural Hazards》2007,42(1):91-103
The tropical storm database used in this study was obtained from the National Oceanic and Atmospheric Administration’s (NOAA)
Coastal Service Center, using the Historical Hurricane Tracks tool. Queries were used to determine the number of storms of
tropical origin that have impacted the State and each of its counties. A total of 76 storms of tropical origin passed over
New York State between 1851 and 2005. Of these storms, 14 were classified as hurricanes. The remaining hurricanes passed over
New York State as weaker or modified systems—27 tropical storms, 7 tropical depressions, and 28 extratropical storms (ET).
Long Island experiences a disproportionate number of hurricanes and tropical storms. The average frequency of hurricanes and
storms of tropical origin (all types) is one in every 11 years and one in every 2 years, respectively. September is the month
of greatest frequency for storms of tropical origin, although the storms of greatest intensity tend to arrive later in the
hurricane season and follow different poleward tracks. While El Nino Southern Oscillation (ENSO) cycles appear to show some
influence, the frequency and intensity of storms of tropical origin appear to follow a multidecadal cycle. Storm activity
was greatest in both the late 19th and 20th centuries. During periods of increased storm frequency and intensity storms reached
New York State at progressively later dates. While the number and timing of storms of tropical origin is likely to increase,
this increase appears to be attributed to a multidecadal cycle, as opposed to a trend in global warming. 相似文献