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1.
Stanley A. Changnon 《Natural Hazards》2008,45(1):1-9
Winter storms are a major weather problem in the United States and their losses have been rapidly increasing. A total of 202
catastrophic winter storms involving ice storms, blizzards, and snowstorms, each causing >$5 million in damages, occurred
during 1949–2003, and their losses totaled $35.2 billion (2003 dollars). Catastrophic winter storms occurred in most parts
of the contiguous United States, but were concentrated in the eastern half of the nation where 88% of all storm losses occurred.
They were most frequent in the Northeast climate district (95 storms), and were least frequent in the West district (14 catastrophic
storms). The annual average number of storms is 3.7 with a 1-year high of nine storms, and one year had no storms. Temporal
distributions of storms and their losses exhibited considerable spatial variability across the nation. For example, when storms
were very frequent in the Northeast, they were infrequent elsewhere, a result of spatial differences in storm-producing weather
conditions over time. The time distribution of the nation’s 202 storms during 1949–2003 had a sizable downward trend, whereas
the nation’s storm losses had a major upward trend for the 55-year period. This increase over time in losses, given the decrease
in storm incidences, was a result of significant temporal increases in storm sizes and storm intensities. Increases in storm
intensities were small in the northern sections of the nation, but doubled across the southern two-thirds of the nation, reflecting
a climatic shift in conditions producing intense winter storms. 相似文献
2.
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
3.
Stanley A. Changnon 《Natural Hazards》2008,47(3):465-470
Increasing losses of life and property and damages to the environment due to sleet and related winter storm conditions have
increased the need for long-term sleet storm data to better assess the point and regional risks of sleet and their long-term
variations. The areas of greatest losses and frequency of catastrophes caused by sleet during 1971–2007 are the Northeast
and Central regions of the U.S. These two regions experienced 72% of all the nation’s sleet losses. Most of the western U.S.
had no damaging sleet-related events or losses. When sleet losses occurred, they tended to be in 2, 3, or 4 adjacent states.
Sleet catastrophes were most common in January with 15 of the 30 events. The earliest storm occurred in October and the latest
in March. The temporal distributions of catastrophes and their losses during 1971–2007 were similar. Both showed a secondary
peak in 1976–1979, a low in 1988–1991, and then high values during the 1996–2007 period. The temporal distributions of damaging
storms and losses indicate an upward trend over time. 相似文献
4.
A unique historical data set describing the 142 storms each producing losses in excess of $100 million in the United States during the 1950–89 period were analyzed to describe their temporal characteristics. The storms caused $66.2 billion in losses (in 1991 values), 76% of the nation's insured storm losses in this period. These extreme storm catastrophes (SCs) were most prevalent in the south, southeast, northeast, and central U.S., with few in and west of the Rocky Mountains. Storm incidences were high in the 1950s, low in the 1960s-early 1970s, and increased in the 1980s. Losses due to SCs peaked in the 1950s, again in the late 1960s, with a lesser peak after 1985. The areal extent of storm losses peaked after 1975 and was least in the 1960s. The temporal variations of the three storm measures (incidence, losses, and extent) did not agree except when they all peaked in the 1950s. Regionally-derived time distributions of SCs showed a marked north-south differences in the United States with a U-shaped 40-year distribution in the northern half of the nation, and a relatively flat trend until a peak in the 1980s in the southern regions. The temporal distributions of hurricane-caused catastrophes differed regionally with occurrences in the prime areas, the southern, southeastern, and northeastern U.S., each quite different. Temporal distributions of thunderstorm and winter storm catastrophes were regionally more uniform. 相似文献
5.
Stanley A. Changnon 《Natural Hazards》2011,59(2):1175-1187
High winds are one of the nation’s leading damage-producing storm conditions. They do not include winds from tornadoes, winter
storms, nor hurricanes, but are strong winds generated by deep low pressure centers, by thunderstorms, or by air flow over
mountain ranges. The annual average property and crop losses in the United States from windstorms are $379 million and windstorms
during 1959–1997 caused an average of 11 deaths each year. Windstorms range in size from a few hundred to hundreds of thousands
square kilometers, being largest in the western United States where 40% of all storms exceed 135,000 km2. In the eastern United States, windstorms occur at a given location, on average, 1.4 times a year, whereas in the western
US point averages are 1.9. Midwestern states average between 15 and 20 wind storms annually; states in the east average between
10 and 25 storms per year; and West Coast states average 27–30 storms annually. Storms causing insured property losses >$379 million and windstorms
during 1959–1997 caused an average of 11 deaths each year. Windstorms range in size from a few hundred to hundreds of thousands
square kilometers, being largest in the western United States where 40% of all storms exceed 135,000 km2. In the eastern United States, windstorms occur at a given location, on average, 1.4 times a year, whereas in the western
US point averages are 1.9. Midwestern states average between 15 and 20 wind storms annually; states in the east average between
10 and 25 storms per year; and West Coast states average 27–30 storms annually. Storms causing insured property losses >1
million, labeled catastrophes, during 1952–2006 totaled 176, an annual average of 3.2. Catastrophic windstorm losses were
highest in the West and Northwest climate regions, the only form of severe weather in the United States with maximum losses
on the West Coast. Most western storms occurred in the winter, a result of Pacific lows, and California has had 31 windstorm
catastrophes, more than any other state. The national temporal distribution of catastrophic windstorms during 1952–2006 has
a flat trend, but their losses display a distinct upward trend with time, peaking during 1996–2006. 相似文献
6.
During 1990–1996 the United States experienced record-setting insured property losses due to numerous weather catastrophes,
each event causing $100 million or more in losses (1991 dollars). The total loss in this 7-year period, after adjustment to
inflation and other factors, was $39.65 billion with $15 billion coming from one event, Hurricane Andrew. In the 1990s, 72
catastrophes occurred, half of the total number in the 40 preceding years, 1950–1989. Although the total loss and the number
of catastrophes were exceptionally high in the 1990s, the average loss per event was $551 million, only slightly more than
the $467 million average for catastrophes during 1950–1989. Furthermore, storm intensities in the 1990s were slightly less
than those during the preceding 40 years, revealing the excess losses of the 1990s to be a result of an extremely large number
of damaging storms causing losses exceeding $100 million. Examination of historical values of most weather extremes including
hurricanes, floods, and tornadoes, did not show an increase during the 1990s, revealing that weather changes were not the
principal cause of more catastrophes. Examination of recent demographic shifts in the U.S. reveals two changes, each based
on major re-locations to higher-valued property concentrated in areas either with a high frequency of damaging storms (Gulf
and East Coast), or to where even a small but intense storm can cause huge losses (urban areas and West Coast). These shifts,
plus the continuing growth of population in other storm-prone areas have greatly increased society's vulnerability to storm
damage. An in-depth analysis of many conditions was required to establish that the high losses and numerous catastrophes of
the 1990s were largely the result of societal changes and not major weather changes.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
7.
Shifting Economic Impacts from Weather Extremes in the United States: A Result of Societal Changes,Not Global Warming 总被引：4，自引：2，他引：4
Loss values from extremes in the U.S. and elsewhere have been more qualitativethan quantitative, but recent pressures for better information have led to newassessments and better estimates of financial losses from extremes. These pressureshave included concerns over potential impacts of more extremes due to global warmingfostered by ever increasing costs to the insurance industry and government from weather extremes; plus a series of massive losses during the past 15 years (drought of 1988–1989,Hurricane Andrew in 1992, and Midwestern 1993 floods). These recent assessmentsattempted to adjust data for societal changes over time and thus derived new and betterestimates of losses for seven major extremes than existed previously. Three extremeshave annual average losses in excess of a billion dollars (1998 dollars) includinghurricanes ($4.2 billion), floods ($3.2 billion), and severe local storms ($1.6 billion).One extreme and its adjusted losses exhibit upward trends (floods), but all others showno increases with time or temporal decreases (hail, hurricanes, tornadoes, and severethunderstorms). Annual national losses during 1950–1997 from the three major extremes, plus four others (hail, tornadoes, winter storms, and wind storms), collectively reveal no upward or downward trend over time, with an average annual loss of $10.3 billion. The quality loss values do not indicate an increase as has been postulated for global warming. The good news is that better estimates of impacts now exist, but the bad news is that they are still estimates and do not include sizable unmeasured losses. If accurate data on the economic impacts from weather extremes are seen as important for scientific research and policy-making for global warming, the U.S. needs a continuing program to adequately measure losses from weather extremes. 相似文献
8.
The speeds of historical cool-season extratropical cyclones along the U.S. east coast, hereafter East Coast Winter Storms
(ECWS), occurring during the period from 1951 to 2006 were computed. Average storm speed was 13.8 ms−1 with stronger storms generally moving faster than weaker storms and faster storms forming during the midwinter months (December–March).
There was no clear trend in ECWS speed during the time period, although considerable season-to-season variability was present.
The monthly and seasonal variations in storm speed could not be attributed to the El Ni?o-Southern Oscillation or North Atlantic
Oscillation (NAO) alone. However, the speed of ECWS was considerably slower when both El Ni?o and the negative phase of NAO
occurred simultaneously. Characteristic patterns in the upper levels of the atmosphere, specifically 300 hPa zonal winds and
500 hPa geopotential heights, were present during periods when ECWS speeds were among the slowest (and separately fastest).
For slow storm speed, these patterns also prevailed during months in which El Ni?o and negative NAO phase occurred. These
patterns were also present during months with extended runs of high oceanic storm surge. This provides a qualitative link
between the atmospheric conditions associated with slow storms and potentially high coastal storm surge impacts. Among the
prime consequences of ECWS speed are extended periods of high storm surge, mainly due to slow-moving storms. The sustained
high tidal levels often lead to substantial damage caused by coastal flooding, overwash, and beach erosion. 相似文献
9.
Hydraulic and flood-loss modeling of levee,floodplain, and river management strategies,Middle Mississippi River,USA 总被引：4，自引：2，他引：2
In this investigation, four scenarios were used to quantify the balance between the benefits of levees for flood protection
and their potential to increase flood risk using Hazards U.S. Multi-Hazard flood-loss software and hydraulic modeling of the
Middle Mississippi River (MMR). The goals of this study were (1) to quantify the flood exposure under different flood-control
configurations and (2) to assess the relative contributions of various engineered structures and flood-loss strategies to
potential flood losses. Removing all the flood-control structures along the MMR, without buyouts or other mitigation, reduced
the average flood stages between 2.3 m (100-year flood) and 2.5 m (500-year), but increased the potential flood losses by
$4.3–6.7 billion. Removing the agricultural levees downstream of St. Louis decreased the flood stages through the metro region
by ~1.0 m for the 100- and 500-year events; flood losses, without buyouts or other mitigation, were increased by $4.3–6.7 billion. Removing the agricultural levees downstream of St. Louis decreased the flood stages through the metro region
by ~1.0 m for the 100- and 500-year events; flood losses, without buyouts or other mitigation, were increased by 155 million
for the 100-year flood, but were decreased by $109 million for the 500-year flood. Thus, agricultural levees along the MMR
protect against small- to medium-size floods (up to the ~100-year flood level) but cause more damage than they prevent during
large floods such as the 500-year flood. Buyout costs for the all the buildings within the 500-year floodplain downstream
of urban flood-control structures near St. Louis are ~40% less than the cost of repairing the buildings damaged by the 500-year
flood. This suggests large-scale buyouts could be the most cost-effective option for flood loss mitigation for properties
currently protected by agricultural levees. 相似文献
10.
Thomas W. Schmidlin 《Natural Hazards》2011,58(1):235-249
Hurricane Ike struck Galveston, Texas, on 13 September 2008, and transitioned to an extra-tropical cyclone on 14 September
as it moved across Ohio with wind gusts of 28–35 ms−1. This was the second most disruptive statewide windstorm in Ohio since 1913, and it caused the largest electrical failure
in Ohio history, with 2 million customers without power. Private insured losses of $1.1 billion were the largest for a natural
disaster in Ohio since 1974. There were seven deaths caused by the storm and 603 injuries. The American Red Cross opened 25
shelters and 86 feeding stations. Hospitals and public water supply systems used backup generators to maintain operations.
Public health consequences of the storm were minimized by good preplanning and preparedness at the local level, by moderate
temperatures during the massive power failure, and the response of governments, the American Red Cross, charitable and service
organizations, and private citizens. 相似文献
11.
Jidong Wu Ning Li Stéphane Hallegatte Peijun Shi Aijun Hu Xueqin Liu 《Environmental Earth Sciences》2012,65(1):161-172
Disaster loss estimates are helpful for managing post-disaster reconstruction and for designing disaster-risk mitigation strategies.
However, most of these estimates in China merely consider direct losses, and only a few include indirect economic losses.
As the most destructive earthquake since the founding of the People’s Republic of China in 1949, the Wenchuan Earthquake that
occurred in 2008 resulted in direct economic damages reached Chinese Yuan (CNY) 845 billion (US $124 billion). The aim of
the study was to estimate indirect economic losses caused by the Wenchuan Earthquake in Sichuan Province through the Adaptive
Regional Input–Output (ARIO) model, which can reflect disaster-related changes in production capacity, ripple effects within
the economic system, and adaptive behaviors of economic actors. The results showed that indirect economic losses in the production
and housing sectors were estimated at 40% of the direct economic losses, i.e., approximately CNY 300 billion; moreover, the
model predicted an 8-year reconstruction period. Several factors contributed to these losses, including significant damages
to key sectors, financial constraints on reconstruction, post-earthquake investment instability, and limits in reconstruction
capacity. Active government support policies post-earthquake are a useful strategy to mitigate the adverse economic impact
of an earthquake in developing countries. 相似文献
12.
The Alxa Plateau has one of the highest frequencies of dust events in China and one of the greatest contributions to East
Asian dust. We compiled climate and dust storm data for the Alxa Plateau based on observational data from ten meteorological
stations from 1960 to 2005. Our analysis showed that Guaizihu and Minqin dust centers had >26 days per year with dust storms
versus 7–13 days for other desert and Gobi regions on the plateau. Variations in dust storm frequency during the study period
showed that dust storms increased during the 1960s (until 1972), decreased until the late 1990s, and then increased slightly
until 2002. About 75.6% of dust storms occurred in March, April, May, June, and July. Between 78.2 and 88.1% of the dust storms
occurred during the daytime and 28.9% of the dust storms occurred between 13:00 and 16:00. The mean durations of dust storms
in the Alxa Plateau ranged from 715 to 3,462 min. The annual number of minutes of dust storms averaged >1,800 min in the western
Alxa Plateau. Dust storm frequency was inversely related to duration: the longer the average duration, the lower the frequency
of such storms. 相似文献
13.
文章依据冰芯、树木年轮等自然记录和历史文献记录,分析了中国北方不同地区近2000年的沙尘事件及其与气候变化的关系。结果表明,在干旱区西部,历史时期的沙尘变化主要受温度变化的制约,无论在10年尺度,还是百年尺度上,沙尘事件与温度变化均表现为显著的反相关,即气候寒冷期与沙尘频发事件相对应,气候温暖期与沙尘发生变弱期一致;在半干旱区,在10年尺度上温度和降水序列与沙尘发生频率均显著负相关,但在百年尺度上沙尘与降水变化的关系更为密切;在干旱区东部,沙尘与气候变化的关系具有明显的过渡性特征,气候变化对沙尘事件的作用主要在百年尺度上体现出来,沙尘与温度记录的负相关比降水更好,在10年尺度上气候与沙尘序列尽管也是负相关,但不显著。通过对现代气象记录的气温、降水变化和沙尘事件频数分析,其结果与历史时期情况基本一致。 相似文献
14.
基于1961 - 2018年冬季逐日降水资料, 研究了新疆北部不同类型暴雪的时空分布和环流特征。结果表明, 冬季新疆北部的局地暴雪日数最多（73.1%）, 区域暴雪次之（20.9%）, 大范围暴雪最少（6.0%）。总暴雪、 区域暴雪和大范围暴雪日数呈显著的增加趋势, 局地暴雪的增加趋势不显著。总暴雪、 局地暴雪和区域暴雪日数在12月最多; 大范围暴雪日数在2月最多。20世纪60 - 80年代, 新疆北部冬季以局地暴雪为主, 暴雪中心主要位于伊犁河谷和塔城地区北部; 90年代至今, 区域暴雪和大范围暴雪日数显著增加, 除伊犁河谷和塔城地区北部外, 阿勒泰地区、 天山北坡中段的暴雪日数增加显著, 乌鲁木齐成为天山北坡新的暴雪中心。新疆北部冬季暴雪的环流形势可分为3类6型, 其中锋区波动类最多, 低槽类次之, 低涡类最少。20世纪90年代前, 锋区波动类最多; 进入21世纪后, 低槽类明显增多。 相似文献
15.
Losses resulting from winter storms contribute a significant part to the overall losses among all natural hazards in most
mid-latitude European countries. A realistic assessment of storm risk is therefore essential for prevention and coping measures.
The paper presents a framework for probabilistic storm risk assessment for residential buildings which is exemplarily performed
for Germany. Two different approaches are described, and results are presented. The hazard-based approach brings together
hazard, vulnerability and building assets to calculate risk curves for each community. The storm-based approach uses loss
information from past storm events to calculate statistical return periods of severe storms. As a result, a return period
of 83 years to the most severe storm series in 1990 is calculated. Average annual losses of €170 million to residential buildings
are calculated for all over Germany. The study demonstrates how the approaches complement each other and how validation is
performed. 相似文献
16.
Estuarine Phytoplankton Responses to Hurricanes and Tropical Storms with Different Characteristics (Trajectory,Rainfall, Winds) 总被引：1，自引：0，他引：1
We examined the short-term (<1 month post-storm) impact of storms [Tropical Storm (TS) Helene in 2000, Hurricane (H) Isabel
in 2003, H Alex, Tropical Depression (TD) Bonnie and TS Charley in 2004] varying in their trajectory, wind and rainfall characteristics,
on water column structure, nutrients, and phytoplankton biomass in North Carolina’s Neuse R. Estuary (NRE). Data are presented
from two sampling programs, ModMon (biweekly) and FerryMon (measurements made every 3 min daily). Helene’s winds mixed the
previously stratified water column, delivering sediment-bound nutrients to the euphotic zone, and localized freshwater input
from Helene was also evident. Mean chlorophyll a concentrations in the mesohaline portion of the NRE, where N was strongly limiting before the storm (molar DIN:DIP < 1),
more than doubled after the storm. Unlike with Helene, the water column was well mixed before passage of Isabel, and nutrient
concentrations were high. As a result, minimal impact on phytoplankton biomass was detected despite Isabel’s high winds and
significant freshwater input. In fact, conditions became less favorable for phytoplankton growth after the storm. Alex was
fast moving and relatively small, but its winds were sufficient to mix the water column. Although data from ModMon suggest
that chlorophyll a was only slightly higher after passage of Alex, FerryMon detected an ephemeral bloom that was missed by ModMon. Overall,
these results suggest that relatively small tropical storms and hurricanes can lead to significant increases in phytoplankton
biomass. However, the phytoplankton response depends on both the characteristics of a particular storm and the physical–chemical
conditions of the water column before storm passage. Finally, the ephemeral bloom that developed as a result of Alex, the
strong response of phytoplankton in the mesohaline portion of the estuary to nutrient inputs, and their patchiness on several
other occasions suggests that storms may create “hot spots” for trophic transfer and biogeochemical dynamics in estuaries.
Adaptive sampling is necessary to capture these features and to fully understand the impact of perturbations such as storms
on estuarine ecosystem functioning. 相似文献
17.
The weather systems that predominantly affect the eastern and northeastern parts of India during the pre-monsoon summer months
(March, April and May) are severe thunderstorms, known as Nor’westers. The storms derive their names from the fact that they
frequently strike cities and towns in the southern part of West Bengal in the afternoon from the north-west direction while
traveling far from its place of genesis over the Bihar plateau. The storms are devastating in nature particularly due to strong
(gusty) winds, heavy rains and hails associated with it. Although these storms are well known for its power of causing damages,
studies on them are relatively few due to their small size and sparse network of observations. To address this important issue,
the evolution of two Nor’westers of 12 March and 22 May 2003 over Kolkata is studied in detail in this paper using hourly
Doppler weather radar (DWR) observations and high resolution Meteosat-5 imageries. In addition, supporting meteorological
reports are used to find the large scale conditions that influence the moisture convergence and vertical wind shear. The genesis
of both the storms is found to be over Bihar-Jharkhand region and beyond the range of the DWR. The satellite observations
are found to be useful in identifying the location and initiation of the storms. The movements of the storms are captured
by the DWR estimated vertical cross-section of reflectivities. The Doppler estimate shows that the 12 March storm had a vertical
extent of about 10–12 km at the time of maturity and that of 22 May reaching up to 18 km signifying deep convection associated
with these events. The genesis, maturity and dissipation are well brought out by the hourly DWR and satellite imageries. The
DWR observations suggest that the systems move at a speed of 20–25 m/s. The DWR estimated precipitation shows a detailed spatial
distribution around Kolkata with several localized zones of heavy rain and this is found to be well supported by the nearby
station observations. This study establishes that DWR observations along with hourly satellite imageries are able to capture
the evolution of Nor’westers. The study also shows that the composite DWR-satellite information is a reliable tool for nowcasting
the location, time and path of movement of Nor’westers. Based on these observations, a conceptual model of the Nor’wester
is proposed. 相似文献
18.
Death tolls from tornadoes in Bangladesh are the highest in the world due to lack of storm warnings, poor communication, weak
housing, and lack of shelters from strong winds in tornadoes and nor’westers. Based on surveys of housing types and designs
in the Tangail district, a household tornado shelter is proposed to be placed in the elevated storage platform that is common
in houses. The shelter is 2 m tall, 1.2 m wide, and 2–4 m long (4.8–9.6 m3 in volume) with the floor of the shelter placed one meter below the floor of the house. Walls are 7–10 cm thick and made
of concrete or an earthen wall stabilized with cement or strengthened with bamboo or bricks. A survey of 200 residents of
the region found nearly universal acceptance for the shelter design, and residents were eager for installation of the household
shelters. The shelter cost is 2,500–10,000 taka (US50 to50 to 200) depending on local material and labor costs but residents
were willing to pay an average of only 1,071 taka (US$21) toward the cost of the shelter. Families with greater income and
land holdings and families in villages with recent tornado experience were willing to spend more for a shelter. A pilot project
to install household tornado shelters in selected villages and monitor their use, along with continued efforts to issue storm
warnings, communicate the warnings, and improve education about storm hazards, will prevent injuries and save lives in Bangladesh
and reduce the descent into poverty that results from losses in severe local storms. 相似文献
19.
Water quality and phytoplankton as indicators of hurricane impacts on a large estuarine ecosystem 总被引：1，自引：0，他引：1
Three sequential hurricanes in the fall of 1999 provided the impetus for assessing multi-annual effects on water quality and
phytoplankton dynamics in southwestern Pamlico Sound, North Carolina. Two and a half years of post-hurricane data were examined
for short- and long-term impacts from the storms and >100 year flooding. Salinity decreased dramatically and did not recover
until May 2000. Inorganic nitrogen and phosphorus concentrations were briefly elevated during the flooding, but later returned
to background levels. Dissolved organic carbon concentrations declined through the whole study period, but did not appear
to peak as was observed in the Neuse River estuary, a key tributary of the Sound. Light attenuation was highest in the fall
to spring following the storms and was best correlated with chlorophylla concentrations. Phytoplankton biomass (chla) increased and remained elevated until late spring 2000 when concentrations returned to pre-storm levels and then cycled
seasonally. Phytoplankton community composition varied throughout the study, reflecting the complex interaction between physiological
optimal and combinations of salinity, residence time, nutrient availability, and possibly grazing activity. Floodwater advection
or dilution from upstream maxima may have controlled the spatial heterogeneity in total and group-specific biomass. The storms
produced areas of shortterm hypoxia, but hypoxic events continued during the following two summers, correlating strongly with
water column stratification. Nitrogen loading to the southwestern sound was inferred from network analysis of previous nitrogen
cycling studies in the Neuse River estuary. Based on these analyses, nutrient cycling and removal in the sub-estuaries would
be decreased under high flow conditions, confirming observations from other estuaries. The inferred nitrogen load from the
flood was 2–3 times the normal loading to the Sound; this estimate was supported by the substantial algal bloom. After 8-mos,
the salinity and chla data indicated the Sound had returned to pre-hurricane conditions, yet phytoplankton community compositional changes continued
through the multi-year study period. This is an example of long-term aspects of estuarine recovery that should be considered
in the context of a predicted 10–40 yr period of elevated tropical storm activity in the western Atlantic Basin. 相似文献
20.
H. M. Poulos 《Natural Hazards》2010,54(3):1015-1023
Hurricanes are one of the major natural disturbances affecting human livelihoods in coastal zones worldwide. Assessing hurricane
risk is an important step toward mitigating the impact of tropical storms on human life and property. This study uses NOAA’s
historical tropical cyclone database (HURDAT or ‘best-track’), geographic information systems, and kernel smoothing techniques
to generate spatially explicit hurricane risk maps for New England. Southern New England had the highest hurricane risk across
the region for all storm intensities. Long Island, western Connecticut, western Massachusetts, and southern Cape Cod, Martha’s
Vineyard, and Nantucket had high storm probabilities and wind speeds. Results from this study suggest that these locations
may be of central importance for focusing risk amelioration resources along the Long Island and New England coastlines. This
paper presents a simple methodology for hurricane risk assessment that could be applied to other regions where long-term spatial
storm track data exist. 相似文献