842 resultados para Severe Storm Forecasting


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The economic loss caused by the storm surge disasters is much higher than that caused by any other marine disaster in China, the loss from the severe storm surge disaster being the highest. Statistics show that there were 62 typhoon landings over the east-southeast coast of China since 1990, three of which, occurring in 1992, 1994 and 1997, respectively, caused the most severe damage. The direct economic losses due to these events are 9.3, 17.0 and 30 billion yuan (RMB, or about 1.7, 2.6 and 3.8 billion USD, respectively), which is much greater than the loss of 5.5 billion yuan (RMB) on an average every year during the 1989-1991 period. This paper makes a comparative analysis of the damage caused by the three events and presents an overview of progress of precautions against storm surge disaster in China. The suggested counter measures to mitigate the loss from the severe storm surge disasters in China is as follows: (1) Raise the whole society awareness of precaution against severe storm surge disaster; (2) Work out a new plan for building sea walls; (3) Improve and perfect the available warning and disaster relief command system; (4) Develop the insurance service in order to promptly mitigate the loss caused by severe storm surge disaster event.

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The paper investigates the relationships between the occurrence of thunderstorms with heavy precipitation (> 30 mm) and atmospheric circulation types. The study covers the period 1951–1998 and is based on a matching span of records of thunderstorm occurrence and daily precipitation totals at 47 weather stations in Poland. A catalogue of circulation types by Osuchowska-Klein, data on frequency of fronts over south-eastern Poland by Niedźwiedź and weather maps were used. In Poland, days with a thunderstorm and more than 30 mm of precipitation are extremely rare and occur mainly in summer. Their recurrence period amounts to about two to four years, with the exception of mountain areas (southern Poland) where they occur nearly every year. The heaviest precipitation on a day with thunderstorm, 166.1 mm, was recorded at a high-mountain station on Mt. Kasprowy Wierch. Apart from this station the highest precipitation was 141.0 mm and only eight stations had at least one record of more than 100 mm. Four regions characterised by different circulation types most favourable for the occurrence of thunderstorms with heavy precipitation were identified. In all of them southerly advection was most favourable for the occurrence of the phenomena studied (Sc, SEc, Sa/c), but that effect was especially prominent in the south-western region. Most of the days with thunderstorm and heavy precipitation coincided with the passing of an atmospheric front over Poland (53.8–81.9% days depending on the station). Days with air-mass thunderstorm and heavy precipitation were rare and mostly occurred in areas of variable topography.

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Discute-se o potencial prognóstico de índices de instabilidade para eventos convectivos de verão na Região Metropolitana de São Paulo. Cinco dos oito dias do período analisado foram considerados chuvosos, com observação de tempestades a partir do meio da tarde. O Índice K (IK) obteve valores abaixo de 31 nos 5 eventos, afetado pela presença de uma camada fria e seca em níveis médios da atmosfera em relação aos baixos níveis. O Índice Total Totals (ITT) falhou na detecção de severidade em 3 dos 5 eventos, apresentando valores inferiores ao mínimo limiar tabelado para fenômenos convectivos (ITT < 44) nesses dias. O Índice Levantado (IL) variou entre -4.9 e -4.3 em todos os 5 casos, valores associados a instabilidade moderada. O Índice de Showalter (IS) indicou possibilidade de tempestades severas em 4 dos 5 casos. Tanto o IS como o CAPE Tv tiveram seus valores fortemente reduzidos em uma sondagem com camada isotérmica entre 910 e 840 hPa. As séries temporais de CAPE Tv e IL mostraram significativa concordância de fase, com alta correlação linear entre ambas. CINE Tv ≈ 0 J kg-1 em associação com baixo cisalhamento vertical e com IS, IL e CAPE Tv, pelo menos moderados, parecem ser fatores comuns em dias de verão com chuvas abundantes e pequena influência da dinâmica de grande escala na área de estudo.

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A seawall was constructed in 1897 along the steep coast of Streckelsberg, Usedom Island to stop the cliff retreat. It was destroyed several times by storm induced sea floods, reconstructed and gradually extended to a length of 450 m. After the severe storm event of 1/2.3.1949, no more repair work was implemented. The ruins were no longer capable of preventing further erosion of the Streckelsberg cliff. A new protective structure became a necessity against ongoing erosion, and to check the lowering of the abrasion platform. The construction of three breakwaters began in 1995. A severe storm occurred on 3/4.11.1995 before their completion. Coastal bottom sediment mapping using a sidescan-sonar carried out two days later showed that a channel system down to a depth of 1.5 m was cut into the sand layer covering the sea floor on both sides of the Koserow Bank. The bottom of these channels was paved with gravel and boulders. This layer was encountered in the whole surveyed area below a mobile sand layer. Discharged bodies of fine sand half a meter high and erosional cavities several m2 in diameter around boulders led to the conclusion that an intensive sediment movement down to a depth of 11 m had taken place during the storm. A storm related direction of sediment discharge could not be identified. The existing section of the breakwaters withstood the severe storm.

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The purpose of this field guide is to provide information on nonindigenous (i.e., non-native) fishes that have been observed in Florida’s marine waters. Introductions of non-native marine fishes into Florida’s waters could be intentional or unintentional, and are likely from a variety of sources, including aquarium releases, escape from aquaculture, loss due to extreme weather events (e.g., flooding from hurricanes), and possibly transfer with ballast water or hull-fouling. Presently the lionfishes (Pterois volitans and P. miles) are the only non-native marine fish species known to be established along the coast of Florida. All other marine fishes in this guide (except the euryhaline species, see below) have infrequent occurrences, occur singly or in small groups, and have not yet become self-sustaining populations. Aquarium releases are one of the major pathways whereby nonindigenous fishes gain access to new environments (Ruiz et al. 1997; Fuller et al. 1999). Most of the nonindigenous marine fishes found in Florida’s waters are thought to be aquarium fishes that either were illegally released into the ocean or escaped captivity (e.g., during severe storm/flooding events). Indeed, south Florida is a hotspot for nonindigenous marine aquarium fishes (Semmens et al. 2004). Increased public awareness of the problems caused by released or escaped aquarium fishes may aid in stemming the frequency of releases. For example, HabitattitudeTM (www.habitattitude.net) is a national public awareness and partnership campaign that encourages aquarists and water gardeners to prevent the release of unwanted aquarium plants, fish and other animals. It prompts hobbyists to adopt alternative actions when dealing with these aquatic plants and animals. (PDF file contains 133 pages.)

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Sediment transport in the nearshore areas is an important process in deciding the coastline stability. The design and effective maintenance of navigable waterways, harbours and marine structures depend on the stability of the sediment substrate and the nature of sedimentation in the nearshore zone. The nearshore zone is a complex environment and the exact relationships existing between water motions and the resulting sediment transports are not well understood. During the rough weather season, when the sediment movement is considerable, processes occurring in the nearshore area are much less understood. Moreover, there is a general lack of field measurements, especially during the time of severe storm conditions. The increasing pressures and the concern on the preservation of the valuable coastal environment have led to the development of shore protection programmes. Conservation not only demands knowledge of what needs to be done, but also requires the basic processes to be fully understood. Considering the fragile nature of barrier beaches and intense occupancy of these areas by man, these coastal features have long been a subject of study by coastal oceanographers, geomorphologists and engineers. The present study is an attempt to understand the sediment movement in relation to beach dynamics, especially in the surf zone, along some part of Kerala coast and the response of the beaches to various forcing functions over different seasons

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O objetivo deste é analisar a relação entre raios e precipitação, sobre diferentes tipos de superfície terrestre e através de estudos de caso de tempestades severas, durante o período de dezembro de 2006 à dezembro de 2008. Os estudos foram feitos dentro de uma área definida pelas coordenadas geográficas 0° a 6° S e 50° a 47° W, abrangendo partes dos estados do Pará, Maranhão e extremo norte de Tocantins.Essa região de estudo foi escolhida por estar localizada em uma área central em relação à localização dos sensores da rede de detecção de raios do Sistema de Proteção Amazônia (RDR-SIPAM) e que contém a maior parte das linhas de transmissão de energia elétrica da região. Os dados de chuva foram coletados por 46 pluviômetros digitais das estações meteorológicas do INMET e HIDROWEB- ANA. Nas análises dos dias de tempestades severas, também foram utilizados dados de pluviômetro de alta resolução temporal operado pela CPRM em Belém. Para classificação dos tipos de superfície e em particular da cobertura vegetal, foram utilizadas as informações de banco de dados sobre Recursos Naturais do IBGE. Para um melhor detalhamento sobre a relação entre raios, precipitação e tipos de superfície, a área de estudo foi dividida em três sub-áreas que possuem características fisiográficas distintas. A Área 1 inclui a Ilha do Marajó e a grande massa d'água da foz do Rio Amazonas e oceano Atlântico próximo. A Área 2 possui 60% de cobertura por floresta. A Área 3 tem 62% de cobertura por áreas agrícolas e/ou pastagens. Os sistemas meteorológicos de larga escala produtores de chuva e raios foram analisados tanto para as 3 áreas consideradas, como nos casos de tempestades severas em torno de Belém. Nessas tempestades foi observado, em quase todos os casos, que os raios antecedem as chuvas. Em geral ficou evidenciada a influencia sazonal na densidade de ocorrência de raios sobre os diferentes tipos de superfície. Todavia, esse trabalho também mostrou que as condições meteorológicas determinam mais amplamente as magnitudes dessa variável. Isso pode ser observado com bastante clareza nos estudos de casos de tempestades severas, onde a ZCIT e as LI`s são fatores determinantes da precipitação e conseqüentemente dos raios ocorridos em Belém.

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The climate and weather have direct implications on society, are factors that can to regulate or restrict human occupation in a determined space. In this way, studies of climate and weather are justified to be extremely necessary for urban planning and economic activities, especially agriculture. The precipitation of hail, which enters in the classification of severe storm, causes large, direct and indirect impacts on society, mainly when it occurs in urban areas. This work aims to study the precipitation of hail, explain what is a severe storms and how hail is formed in clouds, making use of a literature review in geography and also in weather sciences. It is also an aim of this work analyze the genesis, evolution and dissipation of a specific case of precipitation of hail occurred in the metropolitan region of São Paulo, especially in Guarulhos, on 21st of September 21 of 2010, through the use of GOES-12’ satellite’s images and the use of São Roque’s weather radar. And in this way, show the potential impact of hail storms in society and contribute to a greater preparedness of the population, urban planners associations and emergency management, such as municipalities, the civil defense and fireman

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The first hole of the Cape Roberts Project, CRP-1, was drilled in October, 1997, to a depth of 148 metres below the sea floor (mbsf) before being terminated unexpectedly the loss of fast sea-ice seaward of the rig following a severe storm. The site lies in 150 m of water at 77.008°S and 163.755°E, 16 km off Cape Roberts. This part of the report outlines the geologic setting, a gently tilted sequence near the margin of the Victoria Land Basin, and describes the history of the growth of sea ice, which provided the drilling platform, as well as the history of the drilling itself. Core recovery was around 77% in soft and brittle strata to 100 m and 98% below that. The sequence was found to comprise a Quaternary glacigenic interval down to 43.55 mbsf and below this an early Miocene interval that was also glacigenic. Core properties that were studied include fracture patterns, porosity, sonic velocity and magnetic susceptibility. Velocity in particular was useful in relating the cored sequence to the regional seismic stratigraphy. A preliminary assessment suggests that the bottom of the hole is 15 m short of the boundary between seismic sequences V3 and V4. Analytical facilities new to the Antarctic and used for processing samples for the project are described here and include a bench top palynological processing system and a palaeomagnetic laboratory. The core management and sampling system, which recorded over 2000 samples, is also outlined.

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Seafloor sediment mobilization on the inner Northwest Iberian continental shelf is caused largely by ocean surface waves. The temporal and spatial variability in the wave height, wave period, and wave direction has a profound effect on local sediment mobilization, leading to distinct sediment mobilization scenarios. Six grain-size specific sediment mobilization scenarios, representing seasonal average and storm conditions, were simulated with a physics-based numerical model. Model inputs included meteorological and oceanographic data in conjunction with seafloor grain-size and the shelf bathymetric data. The results show distinct seasonal variations, most importantly in wave height, leading to sediment mobilization, specifically on the inner shelf shallower than 30 m water depth where up to 49% of the shelf area is mobilized. Medium to severe storm events are modeled to mobilize up to 89% of the shelf area above 150 m water depth. The frequency of each of these seasonal and storm-related sediment mobilization scenarios is addressed using a decade of meteorological and oceanographic data. The temporal and spatial patterns of the modeled sediment mobilization scenarios are discussed in the context of existing geological and environmental processes and conditions to assist scientific, industrial and environmental efforts that are directly affected by sediment mobilization. Examples, where sediment mobilization plays a vital role, include seafloor nutrient advection, recurrent arrival of oil from oil-spill-laden seafloor sediment, and bottom trawling impacts.

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Predicting the evolution of a coastal cell requires the identification of the key drivers of morphology. Soft coastlines are naturally dynamic but severe storm events and even human intervention can accelerate any changes that are occurring. However, when erosive events such as barrier breaching occur with no obvious contributory factors, a deeper understanding of the underlying coastal processes is required. Ideally conclusions on morphological drivers should be drawn from field data collection and remote sensing over a long period of time. Unfortunately, when the Rossbeigh barrier beach in Dingle Bay, County Kerry, began to erode rapidly in the early 2000’s, eventually leading to it breaching in 2008, no such baseline data existed. This thesis presents a study of the morphodynamic evolution of the Inner Dingle Bay coastal system. The study combines existing coastal zone analysis approaches with experimental field data collection techniques and a novel approach to long term morphodynamic modelling to predict the evolution of the barrier beach inlet system. A conceptual model describing the long term evolution of Inner Dingle Bay in 5 stages post breaching was developed. The dominant coastal processes driving the evolution of the coastal system were identified and quantified. A new methodology of long term process based numerical modelling approach to coastal evolution was developed. This method was used to predict over 20 years of coastal evolution in Inner Dingle Bay. On a broader context this thesis utilised several experimental coastal zone data collection and analysis methods such as ocean radar and grain size trend analysis. These were applied during the study and their suitability to a dynamic coastal system was assessed.

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The effect of the ionosphere on the signals of Global Navigation Satellite Systems (GNSS), such as the Global Positionig System (GPS) and the proposed European Galileo, is dependent on the ionospheric electron density, given by its Total Electron Content (TEC). Ionospheric time-varying density irregularities may cause scintillations, which are fluctuations in phase and amplitude of the signals. Scintillations occur more often at equatorial and high latitudes. They can degrade navigation and positioning accuracy and may cause loss of signal tracking, disrupting safety-critical applications, such as marine navigation and civil aviation. This paper addresses the results of initial research carried out on two fronts that are relevant to GNSS users if they are to counter ionospheric scintillations, i.e. forecasting and mitigating their effects. On the forecasting front, the dynamics of scintillation occurrence were analysed during the severe ionospheric storm that took place on the evening of 30 October 2003, using data from a network of GPS Ionospheric Scintillation and TEC Monitor (GISTM) receivers set up in Northern Europe. Previous results [1] indicated that GPS scintillations in that region can originate from ionospheric plasma structures from the American sector. In this paper we describe experiments that enabled confirmation of those findings. On the mitigation front we used the variance of the output error of the GPS receiver DLL (Delay Locked Loop) to modify the least squares stochastic model applied by an ordinary receiver to compute position. This error was modelled according to [2], as a function of the S4 amplitude scintillation index measured by the GISTM receivers. An improvement of up to 21% in relative positioning accuracy was achieved with this technnique.

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A patient with Graves’ disease was admitted with a thyroid storm. She had severe hypercalcaemia caused by thyrotoxicosis. Treatment was complicated by vomiting and diarrhoea. With intravenous ondansetron, hydration and bisphosphonates, GI symptoms improved and oral thyreostatics could be started. This, combined with bisphosphonate administration, resulted in a mild hungry bone syndrome.