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1.
Water transport in Fourleague Bay is strongly influenced by the discharge of the Atchafalaya River and prevailing wind conditions. In three 50-h intensive surveys, we measured transport through the major inlets of the bay during the three major river discharge/weather regimes of the year: strong frontal passage, high river flow, and calm, low river flow. Wind stress caused significant changes in both transport and water levels. North winds, dominant during winter frontal passages, caused a net export of water. During the high river flow survey, southeasterly winds created an opposing hydraulic pressure gradient in the Gulf of Mexico, diverting river flow into Fourleague Bay. This resulted in an increase in water elevation and the inundation of adjacent marshes. We believe that this high-discharge, southerly wind condition is the major mechanism leading to sheet flow and sedimentation on the marsh. Calm, low-discharge conditions, typical of late summer, produced classic tidally-dominated circulation.  相似文献   

2.
The influence of atmospheric forcing on the flow and heat transports in the lower Chesapeake Bay and the adjacent coastal ocean were studied by comparing nontidal sea level and sea surface temperature variations in this region with meteorological data for 1992. Northeasterly and southwesterly winds caused the greatest changes in mean sea level (greater than 0.25 m) throughout the year. Northeastely winds caused a more rapid response than southwesterly winds, causing sea-level rises in less than 6 h. Barometric pressure changes typically contributed approximately 10% to extreme sea-level variations and were less influential than wind stress in most cases. Wind forcing was also responsible for summer events in which the horizontal water temperature gradient between two near-surface locations in the vicinity of the bay mouth vanished. These zero-gradient events corresponded to inflows and outflows at the bay's entrance caused by northeasterly and southwesterly winds, respectively. Wind-induced advection outside the lower Chesapeake Bay was additionally responsible for extreme heat flux variations. Heat gains and losses during the spring and fall occurred in pulsating events related to wind direction but were probably not connected to lower bay processes.  相似文献   

3.
Upper Chesapeake Bay can be defined as the segment of the bay extending from its head seaward to the mouth of the Potomac Estuary. The Susquehanna River Estuary provides approximately 87% of the total freshwater input to this reach of the bay. With infrequent exceptions, resulting from summer and early fall hurricanes, the Susquehanna River has a well-defined seasonal flow pattern typical of mid-latitude rivers: high discharge in late winter and early spring, followed by low-to-moderate discharge throughout the summer and autumn. Within this general seasonal framework, there are large year-to-year variations in the magnitude of the early spring freshet and of the summer-fall period of low flow. The large seasonal variations in river flow produce significant responses to this fluctuating signal which are manifested in variations in the milieu of upper Chesapeake Bay. Stratification, circulation, sedimentation, nutrient levels, dissolved oxygen levels, and a number of other important and characteristic properties and processes of the upper bay all are closely coupled to variations in discharge of the Susquehanna River. Effects are not limited to the bay proper. Renewal of the tributary estuaries of the upper bay is controlled by variations in flow of the Susquehanna River.  相似文献   

4.
Interest in the coastal dynamics of river plumes has mainly focused on large rivers, but plumes from the more numerous smaller rivers have important local consequences and may, in aggregate, be significant contributors to coastal circulation. We studied the dynamics of the plume from the Saco River in Saco Bay, Gulf of Maine, over a 3-year period. The transport and salinity in the region are governed by river discharge, tides, winds, and interaction with the Western Maine Coastal Current. The dynamics of the flow field vary with location within the plume and discharge. The far-field dynamics of the Saco River plume are dominated by inertial processes (hence qualifying it as a small-scale river plume), during times of low discharge, with low salinity water present both up and downstream of the river mouth, but are dominated by rotational processes during times of high discharge (thus qualifying it as a large-scale river plume), with buoyant water primarily advected downshelf. Near-field dynamics are governed by weak, subcritical flow during low discharge but strongly inertial, supercritical flow during high discharge. Offshore movement of the plume is not governed by Ekman dynamics but is instead a result of discharge, wind-induced vertical mixing, and the geography of the coastline and adjacent islands.  相似文献   

5.
Hurricane storm surge simulations for Tampa Bay   总被引：1，自引：0，他引：1  
Using a high resolution, three-dimensional, primitive equation, finite volume coastal ocean model with flooding and drying capabilities, supported by a merged bathymetric-topographic data set and driven by prototypical hurricane winds and atmospheric pressure fields, we investigated the storm surge responses for the Tampa Bay, Florida, vicinity and their sensitivities to point of landfall, direction and speed of approach, and intensity. All of these factors were found to be important. Flooding potential by wind stress and atmospheric pressure induced surge is significant for a category 2 hurricane and catastrophic for a category 4 hurricane. Tide, river, and wave effects are additive, making the potential for flood-induced damage even greater. Since storm surge sets up as a slope to the sea surface, the highest surge tends to occur over the upper reaches of the bay, Old Tampa Bay and Hillsborough Bay in particular. For point of landfall sensitivity, the worst case is when the hurricane center is positioned north of the bay mouth such that the maximum winds associated with the eye wall are at the bay mouth. Northerly (southerly) approaching storms yield larger (smaller) surges since the winds initially set up (set down) water level. As a hybrid between the landfall and direction sensitivity experiments, a storm transiting up the bay axis from southwest to northeast yields the smallest surge, debunking a misconception that this is the worst Tampa Bay flooding case. Hurricanes with slow (fast) translation speeds yield larger (smaller) surges within Tampa Bay due to the time required to redistribute mass.  相似文献   

6.
A comprehensive study of fine sediment transport in the macrotidal Seine estuary has been conducted, including observations of suspended particulate matter (SPM), surficial sediment, and bathymetric data, as well as use of a three dimensional mathematical model. Tide, river regime, wind, and wave forcings are accounted. The simulated turbidity maximum (TM) is described in terms of concentration and location according to tidal amplitude and the discharge of the Seine River. The TM is mainly generated by tidal pumping, but can be concentrated or stretched by the salinity front. The computed deposition patterns depend on the TM location and are seasonally dependent. The agreement with observations is reasonable, although resuspension by waves may be overestimated. Although wave resuspension is likely to increase the TM mass, it generally occurs simultaneously with westerly winds that induce a transverse circulation at the mouth of the estuary and then disperse the suspended material. The resulting effect is an output of material related to wind and wave events, more than to high river discharge. The mass of the computed TM remains stable over 6 months and independent of the river regime, depending mainly on the spring tide amplitude. Computed fluxes at different cross-sections of the lower estuary show the shift to the TM according to the river flow and point out the rapidity of the TM adjustment to any change of river discharge. The time for renewing the TM by riverine particles has been estimated to be one year.  相似文献   

7.
The Patos Lagoon estuary is an important environment for the life cycle of many species, including the pink shrimp Farfantepenaeus paulensis. This area acts as a nursery ground for the shrimp larvae, which are spawned in a coastal area and transported into the lagoon during spring and early summer (September to December). Harvesting of shrimp occurs from January to May, and yields have varied from around 1,000 to 8,000 tons year?1. This study is based on analysis of river discharge, pink shrimp catches, and wind velocity time series from 1964 to 2004. Negative correlation between pink shrimp catches and river runoff reflects the influence of discharge on the lagoon circulation and, consequently, on the intrusion of salt water and larvae. When river discharge is below average, landward currents forced by SW winds can enhance larval transport into the estuarine area, leading to an increase in pink shrimp captures. Above average river input would force a seaward flow that works as a barrier to ingress of larvae. This is unusual when compared to many other estuarine systems, and the main factor that accounts for this behavior is the morphology (choking) of Patos Lagoon. Interannual variability related to El Niño/Southern Oscillation events also influence pink shrimp production in this area. Low/high shrimp catches are related to El Niño (flood)/La Niña (drought) events. Wind can also impact production through its effect on the southward displacement of larvae from the spawning area. Long-term trends indicate an increase in river discharge around 20 m3 s?1year?1 and a decrease in shrimp catches on the order of 57 tons year?1.  相似文献   

8.
The Environmental Fluid Dynamic Code, an estuarine and coastal ocean circulation model, is used to simulate the distribution of the salinity plume in the vicinity of the mouth of the Cape Fear River Estuary, North Carolina. The individual and coupled effects of the astronomical tides, river discharge, and atmospheric winds on the spatial and temporal distributions of coastal water levels and the salinity plume were investigated. These modeled effects were compared with water level observations made by the National Oceanic and Atmospheric Administration and salinity surveys conducted by the Coastal Ocean Research and Monitoring Program. Model results and observations of salinity distributions and coastal water level showed good agreement. The simulations indicate that strong winds tend to reduce the surface plume size and distort the bulge shape near the estuary mouth due to enhanced wind-induced surface mixing. Under normal discharge conditions, tides, and light winds, the southward outwelling plume veers west. Relatively moderate winds can mechanically reverse the flow direction of the plume. Under conditions of weak to moderate winds the water column does not mix vertically to the bottom, while in strong wind cases the plume becomes vertically well mixed. Under conditions of high river discharge the plume increases in size and reaches the bottom. Vertical mixing induced by strong spring tides can also enable the plume to reach the bottom.  相似文献   

9.
The major Indian rivers bring significant amount of freshwater along with inorganic nutrients and sediment load in to the northern Bay of Bengal (BOB) during the southwest monsoon (SWM); the southern bay does not experience equal freshening. This contrasting pattern may considerably impact the physicochemical features and phytoplankton community composition in this bay and was investigated during a coastal cruise during the SWM covering eight river plumes from both northern and southern bay; phytoplankton pigments and physicochemical parameters were analysed from different depths (0, 10, 25, and 50 m). Significant freshening, stratification and warmer waters were noticed in the northern bay relative to its southern part. Phytoplankton pigment analysis and diagnostic pigment-based size class analysis revealed the dominance of microphytoplankton (mainly diatoms) in the northern bay and were mostly confined to the surface waters. Their abundance was positively correlated with dissolved silicate (DSi) concentrations and inversely with salinity. Nanophytoplankton and picophytoplankton (prymnesiophytes, chrysophytes and cyanophytes) were mostly noticed in the subsurface waters and dominated the southern bay. This finding suggests that the dominance of microphytoplankton in the northern bay may significantly contribute to higher particle flux which has been reported earlier. Therefore, any modification in future river discharge, which is in turn related to the intensity of Indian summer monsoon, will alter the phytoplankton community structure in the coastal BOB and may be further cascaded to the other vital ecosystem components like fisheries resources, organic carbon export flux and benthic production.  相似文献   

10.
The analysis of the aeolian content of marine cores collected off the coast of the Atacama Desert (Mejillones Bay, Chile) suggests that marine sediments can record inter‐annual to inter‐decadal variations in the regional southerly winds responsible for particle entrainment at the surface of the nearby desert. However, the establishment of a simple and direct correlation between the sediment and wind records is complicated by the difference of time scales between the erosion and accumulation processes. The aim of this work is to: (i) assess the inter‐annual variability of the surface winds responsible for the sand movements; and (ii) determine whether the integration over periods of several months completely smoothes the rapid changes in characteristics of the transported and deposited aeolian material. To accomplish this aim, 14 years of 10 m hourly wind speed, measured at the Cerro Moreno (Antofagasta) Airport between 1991 and 2003 and at the Orica Station between 2000 and 2004, were analyzed. For each year, the wind speed statistical distribution can be represented by a combination of two to three Weibull functions. Winds of the lowest Weibull mode are too weak to move the sand grains at the surface of the pampa; this is not the case for the intermediate mode and especially for the highest speed mode which are able to erode the arid surface and transport particles to the bay. In each individual year of the period of study, the highest speed mode only accounted for a limited number of strong erosion events. Quantitative analysis of the distribution of the friction velocities and of their impact on erosion using a saltation model suggests that, although all wind speeds above threshold produce erosion events, values around 0·45 m sec?1 contribute less to the erosion flux. This gap allows separation of the erosion events into low and high saltation modes. The correlation (r = 0·997) between the importance of the third Weibull mode and the extent of higher rate saltation indicates that the inter‐annual variability of the erosion at the surface of the pampa, as well as the transport of coarse particles (>100 μm), are directly related to inter‐annual variations in the prevalence of the strongest winds. Finally, a transport and deposition model is used to assess the possible impact of the wind inter‐annual variability on the deposition flux of mineral particles in the bay. The results suggest that inter‐annual differences in the wind speed distributions have a quantifiable effect on the intensity and size‐distribution of this deposition flux. This observation suggests that a detailed analysis of the sediment cores collected from the bay could be used for reconstructing the inter‐annual variability of past winds.  相似文献   

11.
黄乃和  潘永信 《沉积学报》1992,10(4):111-118
古河口湾沉积环境的恢复主要根据下列证据进行:1.淡化水证据:小个体薄壳生物组合和沉积物中低的硼含量;2.古地理位置处于古河流入海部位;3.潮汐能量大于河流能量,潮汐作用控制了主要沉积过程;4.沉积层序与现代河口湾层序可以类比。虽然河口湾生命短暂,沉积物常被改造,但一个时期的古代河口湾沉积物仍是可以被识别的。  相似文献   

12.
The effect of pulsed events on estuarine turbidity maxima (ETM) was investigated with the Princeton Ocean Model, a three-dimensional hydrodynamic model. The theoretical model was adapted to a straight-channel estuary and enhanced with sediment transport, erosion, deposition, and burial components. Wind and river pulse scenarios from the numerical model were compared to field observations before and after river pulse and wind events in upper Chesapeake Bay. Numerical studies and field observations demonstrated that the salt front and ETM had rapid and nonlinear responses to short-term pulses in river flow and wind. Although increases and decreases in river flow caused down-estuary and up-estuary (respectively) movements of the salt front, the effect of increased river flow was more pronounced than that of decreased river flow. Along-channel wind events also elicited non-linear responses. The salt front moved in the opposite direction of wind stress, shifting up-estuary in response to down-estuary winds and vice-versa. Modeled pulsed events affected suspended sediment distributions by modifying the location of the salt front, near-bottom shear stress, and the location of bottom sediment in relation to stratification within the salt front. Bottom sediment accumulated near the convergent zone at the tip of the salt front, but lagged behind the rapid response of the salt front during wind events. While increases in river flow and along-channel winds resulted in sediment transport down-estuary, only reductions in river flow resulted in consistent up-estuary movement of bottom sediment. Model predictions suggest that wind and river pulse events significantly influence salt front structure and circulation patterns, and have an important role in the transport of sediment in upper estuaries.  相似文献   

13.
Water column nutrients (nitrate, ammonium, soluble reactive phosphate, total Kjeldahl nitrogen, and total phosphorus) and suspended sediments (SS) were measured during one 44-h and two 28-h periods in March 1982 at two stations in Fourleague Bay, Louisiana, which is located at the mouth of the Atchafalaya River, a distributary of the Mississippi River. River water (a source of nitrate, total Kjeldahl nitrogen, total phosphorus, and suspended sediments to Fourleague Bay) flows into the upper reaches of the bay during high tide and frontal overrunning conditions with northerly and westerly winds. During one sampling period, decreasing wind speed and the rising tide resulted in Atchafalaya River water inundating the bay and nitrate concentrations in the upper bay increasing from 30–70 μM to 90–118 μM. Significant variations in nutrients associated with the movement of water masses from the river, marshes, and Gulf of Mexico occurred over several different time scales. Tidal transport occurred over 25-h periods, while frontal passages occurred at 3-d to 5-d intervals. Variability in nutrient and suspended sediment concentrations over these relatively short time scales can be as great as seasonal variability in the bay.  相似文献   

14.
As part of the Microbial Exchanges and Coupling in Coastal Atlantic Systems (MECCAS) Project, crab larvae were collected in the shelf waters off Chesapeake Bay in June and August 1985 and April 1986. We conducted hydrographic (temperature, salinity, nutrients) and biological (chlorophyll, copepods) mapping in conjunction with Eulerian and Lagrangian time studies of the vertical distribution of crab larvae in the Chesapeake Bay plume. These abundance estimates are used with current meter records and drifter trajectories to infer mechanisms of larval crab dispersion to the shelf waters and recruitment back into Chesapeake Bay. The highest numbers of crab larvae were usually associated with the Chesapeake Bay plume, suggesting that it was the dominant source of crab larvae to shelf waters. Patches of crab larvae also were found in the higher salinity shelf waters, and possibly were remnants of previous plume discharge events. The distribution of crab larvae in the shelf waters changed on 1–2 d time scales as a consequence of both variations in the discharge rate of the Chesapeake Bay plume and local wind-driven currents. Downwelling-favorable winds (NW) intensified the coastal jet and confined the plume and crab larvae along the coast. In April during a downwelling event (when northwesterly winds predominated), crab zoeae were transported southward along the coast at speeds that at times exceeded 168 km d−1. During June and August the upwelling-favorable winds (S, SW) opposed the anticyclonic turn of the plume and, via Ekman circulation, forced the plume and crab larvae to spread seaward. Plume velocities during these conditions generally were less than 48 km d−1. The recruitment of crab larvae to Chesapeake Bay is facilitated in late summer by the dominance of southerly winds, which can reverse the southward flow of shelf waters. Periodic downwelling-favorable winds can result in surface waters and crab larvae moving toward the entrance of Chesapeake Bay. Approximately 27% of the larval crabs spend at least part of the day in bottom waters, which have a residual drift toward the bay mouth. There appears to be a variety of physical transport mechanisms that can enhance the recruitment of crab larvae into Chesapeake Bay.  相似文献   

15.
Changes in circulation, water level, salinity, suspended sediments, and sediment flux resulted from Tropical Storm Frances and Hurricane Georges in the Vermilion-Atchafalaya Bay region during September 1998. Tropical Storm Frances made landfall near Port Aransas, Texas, 400 km west of the study area, and yet the strong and long-lived southeasterly winds resulted in the highest water levels and salinity values of the year at one station in West Cote Blanche Bay. Water levels were abnormally high across this coastal bay system, although salinity impacts varied spatially. Over 24 h, salinity increased from 5 to 20 psu at Site 1 on the east side of West Cote Blanche Bay. Abnormally high salinities were recorded in Atchafalaya Bay but not at stations in Vermilion Bay. On September 28, 1998, Hurricane Georges made landfall near Biloxi, Mississippi, 240 km east of the study area. On the west side of the storm, wind stress was from the north and maximum winds locally reached 14 m s−1. The wind forcing and physical responses of the bay system were analogous to those experienced during a winter cold-front passage. During the strong, north wind stress period, coastal water levels fell, salinity decreased, and sediment-laden bay water was transported onto the inner shelf. As the north wind stress subsided, a pulse of relatively saline water entered Vermilion Bay through Southwest Pass increasing salinity from 5 to 20 psu over a 24-h period. National Oceanic and Atmospheric Administration (NOAA)-14 reflectance imagery revealed the regional impacts of wind-wave resuspension and the bay-shelf exchange of waters. During both storm events, suspended solid concentrations increased by an order of magnitude from 75 to over 750 mg l−1. The measurements demonstrated that even remote storm systems can have marked impacts on the physical processes that affect ecological processes in shallow coastal bay systems.  相似文献   

16.
Discharge event frequency, magnitude and duration all control river channel morphology and sedimentary architecture. Uncertainty persists as to whether alluvial deposits in the rock record are a time-averaged amalgam from all discharge events, or a biased record of larger events. This paper investigates the controls on channel deposit character and subsurface stratigraphic architecture in a river with seasonal discharge and very high inter-annual variability, the Burdekin River of north-east Australia. In such rivers, most sediment movement is restricted to a few days each year and at other times little sediment moves. However, the maximum discharge magnitude does not directly correlate with the amount of morphological change and some big events do not produce large deposits. The Burdekin channel deposits consist of five main depositional elements: (i) unit bars; (ii) vegetation-generated bars; (iii) gravel sheets and lags; (iv) antidune trains; and (v) sand sheets. The proportions of each depositional element preserved in the deposits depend on the history of successive large discharge events, their duration and the rate at which they wane. Events with similar peak magnitude but different rate of decline preserve different event deposits. The high intra-annual and inter-annual discharge variability and rapid rate of stage change make it likely that small to moderate-scale bed morphology will be in disequilibrium with flow conditions most of the time. Consequently, dune and unit bar size and cross-bed set thickness are not good indicators of event or channel size. Antidunes may be more useful as indicators of flow conditions at the time they formed. Rivers with very high coefficient of variance of maximum discharge, such as the Burdekin, form distinctive channel sediment bodies. However, the component parts are such that, if they are examined in isolation, they could lead to misleading interpretation of the nature of the depositional environment if conventional interpretations are used.  相似文献   

17.
We examined the processes influencing summer hypoxia in the mainstem portion of Chesapeake Bay. The analysis was based on the Chesapeake Bay Monitoring Program data collected between 1985 and 2007. Self-organizing map (SOM) analysis indicates that bottom water dissolved oxygen (DO) starts to be depleted in the upper mesohaline area during late spring, and hypoxia expands down-estuary by early summer. The seasonal hypoxia in the bay appears to be related to multiple variables, (e.g., river discharge, nutrient loading, stratification, phytoplankton biomass, and wind condition), but most of them are intercorrelated. The winter–spring Susquehanna River flow contributes to not only spring–summer buoyancy effects on estuarine circulation dynamics but also nutrient loading from the land-promoting phytoplankton growth. In addition, we found that summer hypoxia is significantly correlated with the late winter–spring (February–April) northeasterly–southwesterly (NE–SW) wind. Based on winter–spring (January–May) conditions, a predictive tool was developed to forecast summer (June–August) hypoxia using river discharge and NE–SW wind. We hypothesized that the late winter–spring wind pattern may affect the transport of spring bloom biomass to the western shoal or the deep channel of the bay that either alleviates or increases the summer hypoxic volume in the midbay region, respectively. To examine this hypothesis, residual flow fields were analyzed using a hydrodynamic ocean model (Regional Ocean Modeling System; ROMS) between 2000 and 2003, two hydrologically similar years but years with different wind conditions during the spring bloom period. Simulation model results suggest that relatively larger amounts of organic matter could be transported into the deep channel in 2003 (severe hypoxia; frequent northeasterly wind) than 2000 (moderate hypoxia; frequent southwesterly wind).  相似文献   

18.
Suspended-sediment and water samples were collected from San Francisco Bay in 1991 during low river discharge and after spring rains. All samples were analyzed for organophosphate, carbamate, and organochlorine pesticides; petroleum hydrocarbons; biomarkers; and polynuclear aromatic hydrocarbons. The objectives were to determine the concentrations of these contaminants in water and suspended sediment during two different hydrologic conditions and to determine partition coefficients of the contaminants between water and sediment. Concentrations of hydrophobic contaminants, such as polynuclear aromatic hydrocarbons, varied with location of sample collection, riverine discharge, and tidal cycle. Concentrations of hydrophobic contaminants in suspended sediments were highest during low river discharge but became diluted as agricultural soils entered the bay after spring rains. Polynuclear aromatic hydrocarbons defined as dissolved in the water column were not detected. The concentrations sorbed on suspended sediments were variable and were dependent on sediment transport patterns in the bay. In contrast, the relatively hydrophilic organophosphate pesticides, such as chlorpyrifos and diazinon, has a more uniform concentration in suspended sediment. These pesticides were detected only after spring rains. Most of the measured diazinon, at least 98% for all samples, was in the dissolved phase. Measured partition coefficients for diazinon generally were uniform, which suggests that suspended-sediment concentrations were close to equilibrium with dissolved concentrations. The concentration of diazinon sorbed to suspended sediments, at any given sampling site, was driven primarily by the more abundant solution concentration. The concentrations of diazinon sorbed to suspended sediments, therefore, were independent of the patterns of sediment movement.  相似文献   

19.
High rates of wetland loss in the Mississippi deltaic plain have been attributed to a combination of insufficient marsh sedimentation and relative sea-level rise rates of over 1.2 cm yr?1. This study examines contemporary patterns of sediment delivery to the marsh surface by evaluating the contribution of individual marsh flooding events. Strong meteorological effects on water level in Terrebonne Bay often mask the usual microtidal fluctuations in water level and cause flood events to be of unpredictable frequency and duration. Sediment deposited on the marsh surface was collected weekly at two sites. Preliminary results allow the relative contributions of tidal and storm inundations to be calculated. Maximum sedimentation is associated with strong southerly winds both causing increased flooding and mobilizing sediment from open bay areas. Sediment deposition is limited by the availability of suspended sediment and the opportunity for its transport onto the marsh surface.  相似文献   

20.
The paper presents comprehensive statistical analyses of winds and water levels in Mobile Bay, Alabama, based on long-term meteorological and tidal observations at several locations. A procedure has been developed to select the most probable parent distribution function from a list of candidate distributions. The theoretical functions that fit the data best enable us to predict the extreme values of winds and water levels at different return periods. We have demonstrated the importance of dividing the winds into hurricane and nonhurricane seasons and separating astronomical tides from weather-driven water level changes. The statistical analysis suggests that the wind speed averaged over 8 min at Dauphin Island, Alabama, at the 100-year return period would be 48.9 m/s, which is equivalent to a sustained 1-min wind of 205 km/h, a very strong category 3 hurricane on the Saffir-Simpson scale. The probability distribution models predict that the 100-year maximum water level would be 3.23 m above the mean lower low water (MLLW) level at the bay entrance and 3.41 m above the MLLW level near the head of the bay, respectively. Extremely low water levels important to navigation are also found. Application of the predicted extreme winds and surges is illustrated through the development of a storm wave atlas in the estuary. It is expected that the methodology and results presented in this paper will benefit the management and preservation of the ecosystems and habitats in Mobile Bay.  相似文献   

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