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WIND-DRIVEN NEAR INERTIAL OCEAN RESPONSE AND MIXING AT THE CRITICAL LATITUDEZhang, Xiaoqian 2009 May 1900 (has links)
The spatial structure and temporal evolution of sea breeze and the latitudinal
distribution of propagation and mixing of sea breeze driven near-inertial ocean response
in the Gulf of Mexico are investigated using comprehensive data sets and a non-linear
numerical model. Near 30�N, inertial oceanic response is significantly enhanced by a
near-resonant condition between inertial and diurnal forcing frequencies.
Observational results indicate that sea breeze variability peaks in summer and
extends at least 300 km offshore with continuous seaward phase propagation. The
maximum near-inertial oceanic response occurs in June when there is a shallow mixed
layer, strong stratification, and an approximately 10-day period of continuous sea breeze
forcing. Near-inertial current variance decreases in July and August due to the deepening
of the mixed layer and a more variable phase relationship between the wind and current.
River discharge varies interannually and can significantly alter the oceanic response
during summer. During 1993, the ?great flood? of the Mississippi River deepens the
summer mixed layer and reduces the sea breeze response. The near-inertial currents can provide considerable vertical mixing on the shelf in summer, as seen by the suppression
of bulk Richardson number during strong near-inertial events.
Three-dimensional idealized simulations show that the coastal oceanic response to
sea breeze is trapped poleward of 30� latitude, however, it can propagate offshore as
Poincare waves equatorward of 30� latitude. Near 30� latitude, the maximum oceanic
response to sea breeze moves offshore slowly because of the near-zero group speed of
Poincare waves at this latitude. The lateral energy flux convergence plus the energy
input from the wind is maximum near the critical latitude, leading to increased vertical
mixing. This local dissipation is greatly reduced at other latitudes. Simulations with
realistic bathymetry of the Gulf of Mexico confirm that a basin-wide ocean response to
coastal sea breeze forcing is established in the form of Poincare waves. This enhanced
vertical mixing is consistent with observations on the Texas-Louisiana Shelf.
Comparison of the three-dimensional and one-dimensional models shows some
significant limitations of one-dimensional simplified models for sea breeze simulations
near the critical latitude.
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Temporal and Spatial Variation of Gaseous Air Pollutants Monitored at Inland and Offshore Sites in Kao-Ping AreaSu, Ming-min 11 September 2007 (has links)
Air quality was influenced by many factors, in South Taiwan, air pollutants transportation caused by monsoon or sea-land breeze that may caused high air pollution events. Air pollutant generated by human activity on daytime, then transported and accumulated at sea region by land breeze during the nighttime. Unfortunately, air pollutants that accumulated over sea on night may transport back to land by sea breeze on daytime. Besides, monsoon may carry air pollutants from other regions to South Taiwan and caused high air quality event. Till now, air quality influenced by sea-land breeze and monsoon were not verified in South Taiwan.
This study investigated the temporal variation and spatial distribution of air pollutants in the atmosphere around the coastal region of South Taiwan. Ambient air pollutants were simultaneously monitored both inland and offshore. Inland monitoring was conducted at two sites associated with fourteen national air quality monitoring stations, while offshore monitoring was conducted at two sites both in an island and on the boat. A protocol of ambient air quality monitoring was conducted for forty-eight hours. Gaseous air pollutants (i.e. CO, SO2, NOX, THC, and O3) were continuously monitored instrumentally. Data obtained from both inland and offshore monitoring were applied to plot the concentration contour by a software SURFER. Hourly variation of air pollutant concentrations was further used to study the influences of sea-land breezes on the transportation of air pollutants around the coastal region of South Taiwan for different seasons.
In August and November, 2006 and May, 2007, sea-land breeze was observed during sampling period and sea breeze arise from 9:00 A.M. to 24:00 P.M. The average wind velocity was 1~4 m/s during the sampling period. In January and March, 2007, prevail wind direction was north direction and northeast direction (270o~30o), that was influenced by northeast monsoon during the sampling period. The average wind velocity was 2~4 m/s.
The results showed that distribution of air pollutants, including O3, NOX, THC, and CO influenced by sea-land breezes, particularly for ozone. Air pollutants transported to sea region during the nighttime, and transported back at daytime. This phenomenon cause air pollutants accumulated between Kao-Ping and sea region. In general, NOX generated by transportation and industrial process, thus high concentration of NOX appeared during traffic congestion period and at industry region, mainly Kaohsiung city and Linyuang industrial region. However, sea-land breeze effect upon transportation of air pollutants wasn¡¦t obvious for SO2. High SO2 concentration appeared at Linyuang industrial region and Siaogang at daytime, and transported to region along the coast.
During northeastern monsoon season, northeast winds obstructed by Central Mountain Range cause air pollutants accumulated at Kao-Ping region. High NOX concentration appeared at Kaohsiung City and Linyuang industrial region. SO2 accumulated at Siaogang and Linyuang during the nighttime might be caused by high atmospheric pressure system and blew air pollutants to Linbian. CO was accumulated at Siaogang at daytime and transported to Donggang, while THC was accumulated at Donggang whole day.
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Physicochemical Characteristics and Tempospatial Variation of Suspended Particles at Inland and Offshore Sites in KaohsiungTi, Tsung-hung 27 August 2008 (has links)
Kaohsiung region with high percentage (6-8%) of poor air quality (PSI>100) has been announced officially by Taiwan Environmental Protection Administration (TEPA) as the worst air quality region among seven Air Quality Zones (AQZ) in Taiwan. Air pollutant dispersion was influenced by many factors including meteorology and topography. Particulate matter (PM) transportation caused by northeastern monsoon and/or sea land breeze might resulted in air pollution episodes. In summer, PM might be transported back and forth across the coastline of Kaohsiung region by sea land breeze. Particularly, high PM10 concentration has been observed at the inland sites in the daytime due to sea breeze. In autumn and winter, PM could be transported northeasterly to the inland range and covered a huge area of entire region. The objective of this study was to investigate the accumulation of particulate matter in the near-ocean region due to northeastern monsoon and sea-land breeze, and the spatial and temporal distribution of PM in the coastal region of Southern Taiwan.
This study investigated the effects of sea-land breeze and northeastern monsoon on the spatial distribution and temporal variation of particulate matter in the atmosphere around the coastal region of South Taiwan. Particulate matter was simultaneously sampled both inland and offshore during five intensive sampling periods on August 16-17, 2006, November 2-3, 2006, January 24-25, 2007, March 6-7, 2007 and May 2-3, 2007, respectively. Inland monitoring was conducted at two sampling sites associated with fourteen Taiwan ambient air quality monitoring stations, while offshore monitoring was conducted at the Hsiau-Liou-Chiou (HLC) island (approximately 14 km offshore) and on an air quality monitoring boat. In August and November, 2006 and May 2007, sea-land breeze was observed during sampling period and sea breeze arose from 9:00 A.M. to 24:00 P.M. The average wind velocity was 1~4 m/sec during the sampling period. In January and March, 2007, prevail wind direction was north and northeast (300 o ~30 o), that was influenced by northeastern monsoon. The average wind velocity was 2~4 m/sec during the sampling period.
The backward trajectories of air parcel transported toward the inland ambient air quality sampling sites around the coastal region of South Taiwan were plotted during the sea land breeze and northeastern monsoon periods. The results showed that distribution of PM10 was significantly influenced by sea land breezes. During the sea-land breeze periods, sea breezes blown in the early morning would transport the offshore PM10 back to the inland sites in Kaohsiung metropolitan area resulting in high PM10 concentration in the afternoon. On the contrary, high PM10 concentration observed during the northeastern monsoon periods was mainly brought from northerly wind which transported PM10 originated from the northern region (i.e. Tainan and Yunlin Counties) to Kaohsiung metropolitan area.
This study further compared the atmospheric aerosols sampled at Kaohsiung metropolitan area with the resuspended sands blown from top soils collected near the riversides. An enrichment factor (EF) was applied to correlate the downwind atmospheric aerosols at three TEPA sampling sites in Kaohsiung to top soil sources originated from Tachia river, Zhoushui river, Tesngwen river and Kaoping river, respectively. This study revealed that atmospheric aerosols sampled at Southern Taiwan can be correlated to top soil sources near the riversides. Further investigation of enrichment factors indicated that, among four rivers, Kaoping river had the highest correlation to PM10 sampled in Kaohsiung. The enrichment factors were in the order of Kaoping river (EF=0.8~1.9) > Tsengwen river (EF=0.8~2.6) > Zhuos river (EF=1.0~2.8) > Tachia river (EF=1.1~4.2). The results indicated that atmospheric aerosols (i.e. PM10) had relatively higher correlation with the nearest river, Kaoping river, than other three rivers.
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Evolution of diurnal surface winds and surface currents for Monterey BayFoster, Michael D. January 1900 (has links)
Thesis (M.S.)--Naval Postgraduate School, 1993. / Includes bibliographical references (p. 95-98).
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A mesoscale investigation of the sea breeze in the Stellenbosch winegrowing districtDu Preez, Chrisna Barbara. January 2007 (has links)
Thesis (M.Sc.)(Meteorology)--University of Pretoria, 2007. / Includes summary. Includes bibliographical references. Available on the Internet via the World Wide Web.
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Características das circulações locais em regiões metropolitanas do Chile Central / Local Circulation Characteristics over metropolitan areas in Central Chile.Viviana Vanesa Urbina Guerrero 23 April 2010 (has links)
O presente trabalho teve por objetivo caracterizar as circulações locais que se formam na região central do Chile (RCC). Uma análise sinótica para o ano 2004 mostrou que durante o verão a condição de tempo dominante foi de céus claros associados à presença do Anticiclone Subtropical do Pacífico Sul com o deslocamento de baixas pressões litoral que mudam o regime de ventos. Dados da Armada do Chile mostraram que, no litoral da Região de Valparaíso, a amplitude anual de temperatura é de aproximadamente de 8 ºC. Os extremos de temperatura ocorrem entre as 09 e 12 UTC para as mínimas e 18 e 21 UTC para as máximas. O vento apresenta um ciclo anual com domínio da componente oeste no verão e componente leste no inverno. Maiores intensidades estão associadas à passagem de sistemas frontais no inverno. A brisa marítima é melhor caracterizada nos valores médios horários do vento no período de verão, sendo observada a partir das 12 UTC, com ventos de maior intensidade entre 18 e 21 UTC. A brisa terrestre é observada a partir das 00 UTC com ventos de menor intensidade que na brisa marítima. Dados da CONAMA-RM mostraram um ciclo diurno de temperatura bem definido na Região Metropolitana de Santiago com as temperaturas mínimas ocorrendo entre 06 e 09 HL e valores máximos entre 14 e 16 HL. Ao agrupar as estações localizadas dentro e fora dos limites urbanos foi possível identificar o efeito da ilha de calor (IC). Para o período de verão a IC apresentou intensidades positivas e no inverno uma maior freqüência de valores negativos. A intensidade do vento sofre também os efeitos da cidade, observando-se uma redução desta nas estações que se localizam no centro da Grande Santiago. Valores mínimos de intensidade do vento por períodos prolongados levaram a um incremento nas concentrações de material particulado. A diminuição nas concentrações está associada à passagem de frentes e ao incremento na intensidade do vento. Os efeitos da cidade na atmosfera foram estudados com mais detalhamento mediante a utilização do BRAMS. A análise sinótica mostrou uma região de vento fraco e baixo gradiente barométrico na região de estudo para a maior parte do período. Foi possível identificar a brisa marítima com maior intensidade do vento entre 18 e 19 UTC. A brisa terrestre foi identificada na maior parte das noites, com intensidade de vento maior próximo das 04 UTC. As cidades localizadas na RCC apresentam a tendência de resfriar o ar próximo da superfície e modificam a intensidade do vento e os padrões de umidade relativa. Embora os efeitos das cidades tenham sido encontrados, os efeitos da topografia no escoamento são ainda mais importantes, gerando circulações sobre a região central do Chile que não são completamente modificadas pela presença das cidades. / The objective of this work was to characterize the local circulations that are generated in the Central Chile (CC) region. A synoptic analyze for 2004 show that clear sky weather conditions associated to the Subtropical Anticyclone of South Pacific (SASP) was dominant during the summer. Coastal lows moving from north to CC interacts with SASP changing the wind regime. Meteorological data from Armada do Chile showed that on the coast of Valparaíso, the annual temperature amplitude was approximately 8 ºC. Temperature extremes occur between 09 and 12 UTC for minimum and 18 and 21 UTC for maximum values. The wind showed an annual cycle, with dominant direction to west during summer, while in wintertime, wind dominant direction is to the east. Higher values of wind speed are associated with frontal passages during winter. The sea breeze was better seen in the wind mean hourly values between 12 UTC and 21 UTC with higher wind speeds at 18 UTC. Land breeze was observed around 00 UTC, with lower wind speeds than in the sea breeze case. Meteorological data form CONAMA-RM showed a well defined diurnal cycle of temperature in the Metropolitan Region of Santiago with minimum temperatures occurring between 06 and 09 LT and maximum values between 14 and 16 LT. The urban heat island effect was seen grouping urban and non urban meteorological stations. The urban heat island is, in general, positive during the summer but, during the winter, negative values of intensity are frequent. The wind speed also shows the urban effects, with a wind speed decrease in the meteorological station inside the city. Long periods of low wind speed are associated with an increase in the particulate matter concentrations. The decrease in these concentrations is associated with the passage of frontal systems, as well as wind speed increase. The city effects on the atmosphere were studied in more details through the use of BRAMS. The synoptic analysis showed a weak wind region and low pressure gradient in the study region for most part of the period. The sea breeze was identified with higher wind speeds between 18 and 19 UTC. The land breeze was identified in the most part of the nights, with higher wind speeds near 04 UTC. The cities situated in CC have a tendency to cool down the air near to the surface and modify the wind speed and relative humidity patterns. Although the effects of the cities have been found, the topography effects on the wind flow are even more important, generating circulations over Central Chile that are not completely modified by the presence of the cities.
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"Circulações locais em São Paulo e sua influência sobre a dispersão de poluentes" / Local Circulations in São Paulo and its Influence on Pollution DispersionEdmilson Dias de Freitas 29 April 2003 (has links)
Os efeitos causados pela presença de áreas urbanizadas da Região Metropolitana de São Paulo (RMSP), conhecidos por ilha de calor urbana, são estudados através da modelagem numérica e da análise de alguns dados observacionais, coletados no período de inverno de 1999 durante a 1ª Fase intensiva de medidas de campo do Projeto Temático FAPESP Meteorologia e Poluição do Ar em São Paulo e da rede automática da CETESB. Através da utilização de imagens do satélite LANDSAT-5, foi obtido um arquivo de ocupação do solo na RMSP numa resolução de aproximadamente 424 m. Foram definidos dois tipos de ocupação urbana que diferem principalmente na verticalização e espaçamento entre as construções. Simulações realizadas com uma parametrização adequada ao tratamento das propriedades da superfície em áreas urbanas, o modelo RAMS-TEB, mostraram que as fontes antropogênicas de calor de origem veicular são de grande importância no ciclo diurno de temperatura e umidade na RMSP. Uma comparação entre os dados simulados pelo modelo e dados observacionais de superfície apresentou coeficientes de correlações superiores a 0,9 para a temperatura e superiores a 0,8 para a umidade relativa. A interação entre a brisa marítima e a ilha de calor intensifica as zonas de convergência no centro da cidade, podendo ocasionar a re-circulação de poluentes nessa região. Simulações sobre o efeito da urbanização mostram que a ilha de calor urbana faz com que haja uma propagação mais rápida da frente de brisa até o centro da RMSP, que permanece estacionária por algum tempo nessa região. Os efeitos da topografia mostraram-se fundamentais na intensidade da brisa marítima e sua propagação sobre o continente. A presença de grandes corpos dágua, tais como a represa de Guarapiranga e Billings, contribui para a diminuição das amplitudes do ciclo diurno de temperatura na RMSP através das circulações do tipo brisa lacustre geradas pelos mesmos. O uso de um modelo de dispersão mostrou que, com a propagação da frente de brisa para o interior (na direção SE-NW), poluentes emitidos na RMSP são transportados para áreas remotas, diminuindo a concentração dos mesmos nas regiões emissoras. / The effects caused by urbanization in the Metropolitan Area of São Paulo (MASP), known as urban heat island, are studied through the use of numerical modeling and some observed data, collected in the 1999s winter time during the first phase of intensive field measurements from the Thematic Project FAPESP Meteorology and Air Pollution in São Paulo and also from CETESB automatic network. A 424 m resolution land use file was created using LANDSAT-5 satellite pictures where two different kinds of urban regions were identified. The main differences between these regions are the vertical structure and spacing between buildings. Simulations performed with an appropriate parameterization for the treatment of surface properties in urban areas showed that anthropogenic sources due to traffic are of great importance to the temperature and humidity diurnal cycle in MASP. Comparisons between simulated and observed surface data had a correlation coefficient greater than 0.9 for temperature and greater than 0.8 for relative humidity. The interaction between the see breeze and the urban heat island intensify the convergence zones in the center of the city, eventually causing the re-circulation of pollutants in this region. Simulations of the urbanization effects showed that the urban heat island is responsible for a faster propagation of the sea breeze front up to the center of the MASP, remaining stationary in this region for some time. The topographic effects are fundamental in the intensity of the sea breeze and its inland propagation. The presence of large water bodies, as the Guarapiranga and Billings Dams, contribute to a decrease in the temperature diurnal cycle amplitudes because of the lake breeze circulations generated by them. The use of a simple dispersion model showed that with the propagation of the sea breeze front to the countryside (in the direction SE-NW), pollutants emitted in MASP are transported to remote areas, causing a decrease in the concentration of these pollutants in the source region.
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Self-representation in Selected Poems of Gu Taiqing (1799-1877)Chang, Li-Ting 20 October 2021 (has links) (PDF)
Gu Taiqing 顧太清 (1799-1877) is one of the most famous and prolific female writers in the late Qing. In this thesis, I focus on her poems and lyrics on three important subjects, self-portrayals, plum blossoms, and Qingfengge 清風閣 (Clear Breeze Pavilion), in her two poetry collections, Tianyou geji 天遊閣集 (Collected Poems of Heavenly Travels Studio) and Donghai yuge 東海漁歌 (Songs of the Fisherman of the Eastern Sea), in order to advance the current scholarship on this female author and Ming-Qing women’s writings and reveal the uniqueness of Gu’s poetry. My study addresses how she represents herself, recounts her life experiences, and engages in the poetic tradition established by men. By examining her voices and images embedded in her poems, I argue that she creates her own expressions of female voices as an elite woman, a mother, and a female companion for her friends and her husband through the incorporation of her life experiences, both inside and outside her inner quarters. Most female figures portrayed by male poets are desired, static, subordinate, and longing for their absent lovers in their boudoir. Differentiating from the common women’s image, Gu shows her literary creation and women’s subjectivity by taking an active role, as opposed to a passive one. She describes a self-contented life and creates a delightful atmosphere in the spatial setting of her inner quarters. She also writes about her activities outside her boudoir and narrates her travel experiences as a female poet in her poems, in which she constructs her image as a subject that appreciates nature and is emotionally attached to her family. Moreover, my study discovers the approaches that she takes to negotiate between her reputation as a talented poet and her image as a learned lady, given the high moral standard expected from the late Qing elite women. Constructing her image associated with Confucian morality, she highlights her dedication to womanly learning and suggests that women’s literary talent and virtue are reconcilable.
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Webbportal för nätverks-övervakning : Utveckling av en Single Page Application i .NET och JavaScript / Web Portal for Network Monitoring : Development of a Single Page Application. NET and JavaScriptBorgström, Joakim, Gerdin, Stefan January 2013 (has links)
I detta projekt jobbar vi för att skapa ett program åt Infozone Sverige AB tillsammans med professionella utvecklare från företaget. Programmet är en webbportal som används till att övervaka och visa driftinformation om ett nätverk. Tanken är att denna portal skall integreras i ett ännu ej byggt system för nätverksövervakning som Infozone senare kan sälja till kund. Produkten tas fram med Scrum samt testdriven utveckling och under utvecklingen jobbar laget med bestämda metoder och SOLID-principerna för att säkerställa programmets kvalitet. Webbportalen utnyttjar moderna teknologier och ramverk för webbutveckling, bland annat är den en Single Page Application (SPA), använder följsam webbdesign och utnyttjar Microsofts .NET-plattform. I slutändan är inte alla ställda krav uppfyllda, men i och med att Scrum används är programmet fungerande vid projektets avslutande. De krav som faktiskt implementeras görs så till fullo. Vidare visar det sig att det inte alltid är bäst att använda de senaste ramverken, utan mer beprövade metoder och teknologier kan i vissa fall vara mer lämpliga. / In this project we are creating a program for Infozone Sverige AB together with professional developers from the company. The program is a web portal which will be used to monitor and show system status of a network. The plan is that this web portal will be integrated into a not yet built network monitoring system which Infozone later can sell to their clients. The product is developed using Scrum together with test-driven development and during the development the team is working with certain methods and the SOLID principles to ensure the quality of the program. The web portal takes advantage of modern technologies and frameworks for web development, among other things it is a Single Page Application (SPA), uses responsive design and Microsoft’s .NET platform. In the end not all requirements are met, but because we are using Scrum, the program is functioning at the end of the project. The requirements that are implemented, are fully so. Furthermore, it is shown that it is not always best to use the latest frameworks, but the more tested methods and technologies can in some cases be more appropriate.
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Análise da circulação de brisa marítima e seus impactos sobre a precipitação na Região Metropolitana de São Paulo por meio do modelo ARPS / Sea breeze circulation analysis ant its impacts over Metropolitan area of São Paulo precipitation using ARPS modelVemado, Felipe 11 May 2012 (has links)
Eventos de brisa marítima (BM) são comuns na Região Metropolitana de São Paulo (RMSP). No verão, em particular, estão associados com tempestades, chuvas, rajadas de vento, granizo e descargas atmosféricas intensas na RMSP. Utilizou-se o método de OLIVEIRA e SILVA DIAS (1982) para identificar os eventos de BM. Todos os eventos de BM entre 2005 e 2008 foram analisados por meio de medições de superfície, altitude, radares meteorológicos, satélite e modelagem numérica da atmosfera. Em geral, a penetração da frente de BM na RMSP ocorre entre o meio e o fim da tarde com aumento da temperatura do ponto de orvalho. Ainda, o ambiente urbano mais aquecido tende a intensificar as tempestades que podem produzir enchentes, alagamentos, queda de árvores, entre outros impactos socioeconômicos muito significativos. A partição anual pluviométrica devido a BM foi estimado com o radar meteorológico de São Paulo. Os resultados indicam um núcleo de máxima precipitação acumulada com pico de 600 mm sobre a RMSP, muito maior que no entorno dessa. A modelagem com o ARPS permitiu simular condições médias espaciais em baixos, médios e altos níveis de diversas variáveis dos eventos analisados. As simulações de controle e específicas com ARPS sugerem um impacto significativo da cobertura do solo na distribuição espacial da precipitação. As análises foram complementadas com medições do radar meteorológico MXPOL e demonstram a importância desse tipo de sensoriamento remoto na detecção e previsão a curtíssimo prazo da penetração de BM, com alta resolução espaço-temporal. / Sea breeze events (SB) are common in Metropolitan area at São Paulo (MASP). Particularly, in the summer, SB triggers over MASP deep convection, heavy rainfall, wind gusts, hail and lightning. OLIVEIRA and SILVA DIAS (1982) method was used to identify the SB events. SB events between 2005 and 2008 were analysed by means of surface and upper air measurements, weather radar, satellite and numerical modelling. In general, the SB front penetrates in MASP between midafternoon and evening increasing dew point. Moreover, the warmer urban environment tends to intensify storms that produce flooding, falling trees, among other large socioeconomic impacts. The annual rainfall partition due to SB was estimated using the São Paulo weather radar. The results indicate a core of maximum rainfall accumulation of 600 mm over MASP, much larger than that in the vicinity. The modelling with ARPS allowed simulate conditions spatial average in low, medium and upper levels of several variables of the analysed events. Moreover, the ARPS system was used to simulate SB with control and specific runs. Results suggest significant impact of surface cover on rainfall distribution. MXPOL weather radar measurements of SB were important in detecting and nowcasting SB inflow at very high spatial and temporal resolution.
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