Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
Características de cristais de gelo observados em um sistema de nuvens na Amaz?nia durante o experimento TRMM-LBA
Costa, Alexandre Araujo;Campos Filho, Mucio Costa;Santos, Antonio Carlos Santana dos;Oliveira, José Carlos Parente de;
Revista Brasileira de Meteorologia , 2012, DOI: 10.1590/S0102-77862012000200003
Abstract: during the months of january and february 1999, the trmm/lba (tropical rainfall measuring mission/large scale biosphere-atmosphere experiment in amazonia) campaign took place, in which microphysical properties of deep convective clouds were investigated. the experiment was part of an international effort to calibrate trmm satellite sensors for precipitation, radiation and atmospheric electricity studies. the data used in the present work were collected by instruments on board north dakota university's citation ii aircraft, including data from a set of spectrometric probes that measured concentration and size of ice crystals, with distinction to the 2dc (two-dimensional cloud) probe. this instrument identifies not only number concentration and size of the cloud particles, but also their shape. the aircraft performed several flights during the trmm/lba experiment and data from 10 february 1999 are analyzed in this paper. inside the cloud system, ice crystals were observed in a variety of shapes and sizes. a certain agreement was found between the crystal shape and the expected patterns of ice crystal growth as a function of temperature and humidity, but crystal habit superposition was also found, suggesting the existence of mixture between air parcels from different cloud regions and indicating that crystal sedimentation plays a significant role in the evolution of the microphysics of deep convective clouds. it was also noted that the size distribution of the ice crystals follows approximately a power law.
Compara??o do perfil de vento medido por Radiossondas e por um SODAR durante o experimento DRYTOWET-AMC/LBA
Santos e Silva, Cláudio Moisés;Lyra, Roberto Fernando da Fonseca;
Revista Brasileira de Meteorologia , 2009, DOI: 10.1590/S0102-77862009000300009
Abstract: the horizontal wind profiles measured by a sodar and radiosondes during the drytowet-amc/lba experiment are compared. the analysis were made considering three layers: from surface up to 500 m, from 500 up to 1000 m and from 1000 to 1500 m. in the first layer the wind field profiles are in good agreement, however, the correlation values between sodar and radiosonde data, gets significantly lower for the other two layers. the results suggest that the sodar data should better be used if operating from surface up to 500 m and with greater vertical resolution.
Nuvens escuras austrais. I - Contagem de estrelas e extin es visuais Nuvens escuras austrais  [cached]
Gilberto Carlos Sanzovo,Maria Alcina Braz
Semina : Ciências Sociais e Humanas , 1986, DOI: 10.5433/
Abstract: Star counts of 3 southern dark clouds were performed using the techniques developed by Dickman (1976) in order to determine the visual extinction, AV, Using the ESO (B), SRC-J and ESO (R) plates, counts were made in the cloud and comparison fields, the latter being presumably free of obscurity. Various globules were identified in the clouds and parameters as dimension and visual extinction were estimated. Neste trabalho, o método de contagem de estrelas desenvolvido por Dickman (1976) foi aplicado a 3 nuvens escuras do Hemisfério Celeste Sul, com o objetivo de determinar a sua extin o visual, A y As nuvens foram selecionadas a partir dos Atlas ESO (B), SRC-J e ESO (R) e as contagens feitas em 2 campos distintos: o campo da nuvem escura e o campo de compara o, livre de obscurecimento. A partir dos valores determinados de A y, vários glóbulos escuros foram reconhecidos e suai dimens es estimadas.>
Fluxos de CO2 do solo na floresta nacional de Caxiuan , Pará, durante o experimento ESECAFLOR/LBA Soil CO2 efflux in Caxiuan national forest, Pará, during the ESECAFLOR/LBA experiment  [cached]
Jo?o de Athaydes Silva Júnior,Antonio Carlos L?la da Costa,Pedro Vieira de Azevedo,Rafael Ferreira da Costa
Revista Brasileira de Meteorologia , 2013,
Abstract: O experimento ESECAFLOR/LBA foi conduzido na Floresta Nacional de Caxiuan , Pará, e este artigo procura investigar os efeitos do estresse hídrico sobre a respira o do solo. Duas parcelas de 1 hectare foram instaladas em janeiro de 2002. Uma parcela (A) permaneceu em condi es naturais e foi usada como controle, enquanto que na parcela de exclus o (B) foram instalados painéis plásticos para que aproximadamente 70% da precipita o fosse excluída. Os dados foram coletados mensalmente de janeiro a dezembro de 2005. Durante o ano de 2005 houve 2.211,6 mm de precipita o na ECFPn, ou seja 9,96% acima da média de 2.011,2 mm. As médias da umidade do solo foram de 15,6±9,2 e 9,5±3,4% nas parcelas A e B, respectivamente. As médias da temperatura do solo para as parcelas A e B foram de 25,6±0,4 e 25,7±0,5 oC, respectivamente. As médias dos fluxos de CO2 no solo nas parcelas A e B foram de 3,46±0,44 e 3,21±0,84 μmolCO2 m-2s-1, respectivamente. Com a exclus o de parte da chuva na parcela B, houve uma redu o de 7,23% nos fluxos de CO2 no solo (0,25 μmolCO2 m-2s-1), 39,1% na umidade do solo (6,1p.p.), e um aumento de 0,39% na temperatura do solo (0,1oC). A umidade do solo na parcela B foi menor do que na parcela A, devido ao sistema de exclus o da chuva, no entanto no início do ano, devido a reformas que o mesmo passou esses valores estiveram próximos. The ESECAFLOR/LBA experiment was carried out at the Caxiuan National Forest, Pará State, and this article intends to investigate the effect of hydrological stress on the total soil respiration. Two adjacent 1 hectare plots were defined in January 2002. One plot remained in its natural conditions and was used as a control (A), while in the exclusion plot (B) plastic cover panels were installed in order to drain about 70% of the total rainfall to outside of the plot. Accumulated monthly rainfall was recorded from 2005 January to December. During 2005 the rainfall over the ECFPn was 2,211.6 mm, or 9.96% above the mean of 2,011.2 mm. The average soil moisture was 15.6±9.2 and 9.5±3.4% in the plots A and B, respectively. The average soil temperature was 25.6±0.4 and 25.7±0.5 oC, for the A and B plots, respectively. The average soil CO2 flux was 3.46±0.44 and 3.21±0.84 μmolCO2 m-2s-1 in the A and B plots, respectively. With the exclusion of part of rain in plot B, it had a reduction of 7.23% in the soil CO2 flux (0.25 μmolCO2 m-2s-1), 39.1% in the soil humidity (6.1p.p.), and an increase of 0.39% in the soil temperature (0.1oC). The soil moisture in parcel B was lesser than in the parcel A, due to the exclusion system of r
Variabilidade espacial da chuva durante o experimento LBA/TRMM 1999 na Amaz?nia
Fisch, Gilberto;Vendrame, Iria F.;Hanaoka, Paulo Cesar de Melo;
Acta Amazonica , 2007, DOI: 10.1590/S0044-59672007000400013
Abstract: the purpose of this work was to study the space variability of the convective rainfall in amazonia during the lba/trmm experiment 1999. a dataset of 37 rain gauges (split in 4 networks and geographically located with a maximum distance amongst them around 50 km) has been used to provide rainfall measurements for the period from mid dec 1998 until end of feb 1999, which is the peak of the rainy season at rondonia (southwest of amazonia). the methodology of interstation correlation (based on conditional probability and assuming a bivariate mixed lognormal distribution) have been applied to computed daily rainfall and the results had shown that rainfalls occurring within a 1 km of radius have a high correlation coefficient (ranging from 0.7 up to 0.9) representing the validation of a point rainfall measurement. the adjusted curve of the correlation coefficient (r) vs distance (d in km) was: r = 0.72 - 0.15 ln (d).
Condensa??o a superfície na Amaz?nia em área de pastagem durante o experimento LBA/SMOCC: estudo de casos
Andrade, Antonio Marcos Delfino De;Moura, Marcos Antonio Lima;
Revista Brasileira de Meteorologia , 2011, DOI: 10.1590/S0102-77862011000300002
Abstract: the condensation is an indispensable variable to the knowledge of some hydrologic and biologic process which is involved in a great natural process variety, which acts in different space and secular scales. in the amazon is common to see such phenomenon on the dawn period, mainly in dry times. inside the structure of large scale biosphere-atmosphere experiment in amazonia (lba), the smoke, aerosols, clouds, rainfall and climate (smocc) campaign was realized in a period between september and november 2002, on the old abracos's small experimental farm, located in rond?nia, where was possible to make detailed measurements from of the chemical and physical properties of the atmosphere, the formation and waste of water vapor's surface. according to the results, the condensation formation occurred during nocturnal period for presenting propitious conditions for its event. to the events analyzed in this work, it was observed that its formation and maintenance had been in function of the wind intensity. however, it is possible to argue that the calmness is a determinative factor for the condensation sprouting.
Nuvens invisíveis. A poética da latência e da nuance no conto “Nenhum, Nenhuma” de Jo o Guimar es Rosa
Marília Librandi-Rocha
Ellipsis , 2011,
Abstract: Este texto prop e os conceitos “latência” e “nuance” para descrever o efeito de suspens o criado pela fic o de Jo o Guimar es Rosa. No primeiro momento, definem-se os termos “latência” e “nuance” em rela o à imagem das nuvens. Como matéria em suspenso sempre mutável, é impossível inscrever o movimento das nuvens em uma forma fixa, a n o ser que se crie uma escrita latente, apta a captar a nuance das formas em morfose. Em seguida, analisa-se o conto “Nenhum, Nenhuma”, de Primeiras Estórias (1962), como uma pequena obra-prima da latência, mostrando que passado, presente e futuro se materializam simultaneamente na imagem enigmática que se busca entender: “nuvens s o para n o serem vistas;” imagem que parece delinear o inconsciente de uma sensibilidade estética pós-1945.
A acesso e uso de arquivo digitais nas nuvens
Eliana Maria dos Santos Bahia
Revista ACB , 2010,
Abstract: Resenha de livro: TAURION, Cezar. Cloud computing: computa o em nuvem: transformando o mundo da tecnologia da informa o.Rio de Janeiro:Brasport, 2009. 205p. ISBN:978-85-7452-423-8
Intercompara??o entre quatro métodos de estimativa da altura da camada limite convectiva durante o experimento RaCCI - LBA (2002) em Rond?nia - Amaz?nia
Santos, Luiz André R. dos;Fisch, Gilberto;
Revista Brasileira de Meteorologia , 2007, DOI: 10.1590/S0102-77862007000300005
Abstract: this work has like objective to do a comparison between four different methods of estimate of the convective boundary layer (cbl) height, utilizing data obtained by the sodar and radiossound, during the dry - to - wet campaign of the racci - lba experiment in rondonia, (2002). the four methods of estimate utilized were: the parcel method; the richardson number method; the profiles method; and a direct measurement method by sodar. the results showed that the parcel method overestimated the heights of the cbl (15% at 08:00 lt and 14:00 lt, and 30% to the other hours), in most of cases analyzed, obtaining a short determination index (r2), when compared with the others methods. the richardson number method and the profiles method presented very similar heights, with average differences less than 50 m, achieving a r2 value about 0,97, during the beginning of the rainy station. the sodar data was not adequate at the first hours of the morning, showing that the equipment takes the residual boundary layer (from the previous day) and not the shallow convective boundary layer, in development.
O consultor e o manejo de clima grupal
Edela Lanzer Pereira de Souza
Psicologia: Ciência e Profiss?o , 1982, DOI: 10.1590/s1414-98931982000100004
Abstract: O trabalho aborda o manejo de clima como atividade deliberada, passível de treinamento. Requer capacita o conceitual, técnica e humana. Inicialmente é feita uma resenha bibliográfica sobre as abordagens de clima. Depois s o analisados alguns momentos críticos, a saber: os contatos iniciais, a manuten o do clima, depress es e conflitos, brincadeiras e risos. Finalmente s o tratados alguns estereótipos profissionais que dificultam a empatia entre consultor e clientes.
Page 1 /100
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.