22 results on '"FABRICIO, A. C."'
Search Results
2. Key Practices for Incorporating Sustainability in Project Management from the Perspective of Brazilian Professionals
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Ricardo P. F. Ferrarez, Claudia G. B. do Valle, Jeferson C. Alvarenga, Fabricio da C. Dias, Diego A. Vasco, André L. A. Guedes, Christine K. Chinelli, Assed N. Haddad, and Carlos A. P. Soares
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sustainability ,project management ,key factors ,environmental efficiency ,compliance ,social responsibility ,continuous improvement ,lessons learned ,project success ,Renewable Energy, Sustainability and the Environment ,Geography, Planning and Development ,Building and Construction ,Management, Monitoring, Policy and Law - Abstract
Project management has incorporated sustainability concepts, but their relationship is still widely discussed. In this article, we research key practices for incorporating sustainability in project management from the perspective of 919 Brazilian professionals with experience in the field. We used factor analysis to explore the relationship between 37 sustainability practices. The results showed that these sustainability practices can be grouped into five key practices: environmental efficiency, compliance, social responsibility, continuous improvement and lessons learned, and project success. We also used word clouds to highlight the main themes in the practices encompassed by each key practice. The results contribute to project leaders and other project management professionals directing their efforts toward improving sustainability actions related to these practices in project management processes.
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- 2023
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3. Impacts of a large extra-tropical cyclonic system in Southern Brazilian Continental Shelf using the COAWST model
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Fabricio S. C. Oliveira, Luis Felipe Ferreira de Mendonça, Rose Ane Pereira de Freitas, Carlos A. D. Lentini, Antônio F. H. Fetter-Filho, Douglas Lindemann, and Mauro M. Andrade
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geography ,geography.geographical_feature_category ,Continental shelf ,Climatology ,Climate Forecast System ,Cyclone ,Thermohaline circulation ,Tide gauge ,Forcing (mathematics) ,Southern Hemisphere ,Sea level ,Geology - Abstract
The Southern Brazilian Continental Shelf (SBCS) is an area with great ecological and economic importance to Brazil. In this region can be observed the recurrent passage of frontal systems and extra-tropical cyclones, which are more frequent during the winter months of the southern hemisphere. These systems act on the ocean surface layers as direct driving forces, which may change the thermohaline structure of the water column and induce sea level perturbations. This study used the coupled ocean-atmosphere regional model (COAWST) to evaluate the effect of the passage of a frontal system associated with an extra-tropical cyclone. The ROMS oceanic model was configured with two nested grids, in order to solve the hydrodynamic processes at different scales. The parent (20–40° S/40–60° W) and child (25–29.3° S/46.3–50° W) grid comprise the coastal region, with a horizontal resolution of 1/9° and 1/27°, respectively, with 32 vertical levels. The initial conditions are the Global Analysis Forecast from CMEMS and forcing files used the Climate Forecast System v.2 (CFSv2) data, from NCEP. This event took place on the continental shelf of the State of Santa Catarina, in September of 2016. The model results were compared to remote sensing data and to the tide gauges from the City of Imbituba (State of Santa Catarina, Brazil). The comparison showed a correlation higher than 78 % between sea level rise data and the model results. The filtering of sea level data made it possible to identify the meteorological component in the model results. The comparison between the tidal-gauge and the model output presented values under 25 cm. The model was capable of representing the sea level anomalies propagation associated with the passage of the atmospheric frontal system. The model output showed the presence of a sea level anomaly propagating northward along the continental shelf at 480 km day−1, probably associated with the presence of a coastal-trapped wave.
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- 2021
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4. Mesoscale eddy detection in satellite imagery of the oceans using the Radon transform
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Paulo S. Polito and Fabricio S. C. Oliveira
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010504 meteorology & atmospheric sciences ,Pixel ,Radon transform ,010505 oceanography ,Mesoscale meteorology ,Geology ,Image processing ,Sea-surface height ,Aquatic Science ,01 natural sciences ,Synthetic data ,Oceanography ,Feature (computer vision) ,ONDAS (OCEANOGRAFIA) ,Rotation (mathematics) ,Physics::Atmospheric and Oceanic Physics ,0105 earth and related environmental sciences ,Remote sensing - Abstract
The present study proposes a new methodology to identify mesoscale eddies that are ubiquitous in the ocean and can be observed in a variety of satellite images. Our focus is on eddies with mean diameter of 100–500 km. The proposed methodology uses an algorithm based on the Radon transform. The basic premise is that the inverse Radon transform of a circularly symmetric feature is angle-independent. Therefore, the more constant the Radon transform of an image is with respect to the rotation angle, the more circularly symmetric the image is. Although our method is based on circular symmetry it is able to detect non-symmetric eddies using a sensitivity parameter that quantifies the deformation. Our method is effective to determine how circular a feature observed in a satellite image is, and suggest whether it is an eddy or not, based on geometric criteria. A series of tests with synthetic data were performed to assess the sensitivity to spectral content and aspect ratio detectable by the method. Another sequence of tests was carried out with images of chlorophyll-a concentration, sea surface temperature and sea surface height. In the three cases five areas of 100 × 50 pixels were selected and filtered with exactly the same algorithm and parameters. The two sets of tests indicate that the proposed method was able to identify eddies in a single time series of satellite images and in multiple series of different variables. The main advantage of this method in comparison with either automatic ones based on dynamics and geometry or manual methods is its ability to observe eddies in multiple data sets of different variables.
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- 2018
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5. Impacts of a large extra-tropical cyclonic system in Southern Brazilian Continental Shelf using the COAWST model
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Mendonça, Luis Felipe F., primary, Fetter-Filho, Antônio F. H., additional, Andrade, Mauro M., additional, Oliveira, Fabricio S. C., additional, Lindemann, Douglas S., additional, Freitas, Rose Ane P., additional, and Lentini, Carlos. A. D., additional
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- 2021
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6. MODELLING AN EXPERIMENT TO MEASURE THE SPEED OF GRAVITY IN SHORT DISTANCES USING ROTATING MASSES
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Fabricio Junior, C. A., primary, Sanchez, E, additional, Frajuca, C, additional, Bortoli, F. S., additional, Magalhaes, N. S., additional, Da Silva, W. C., additional, Da Silva, D. M., additional, and Souza, R. C., additional
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- 2021
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7. Seasonal and regional variation in egg size of the Argentine anchoita (Engraulis anchoita) in the southeastern Brazilian Bight
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Maria de Lourdes Zani-Teixeira, Mario Katsuragawa, Jefferson T. Turner, Fabricio S. C. Oliveira, Nayara C. Tannure, and Jana Menegassi del Favero
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0106 biological sciences ,Fishery ,Engraulis ,biology ,Regional variation ,010604 marine biology & hydrobiology ,Aquatic Science ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,Argentine anchoita - Published
- 2017
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8. Impacts of a large extra-tropical cyclonic system in Southern Brazilian Continental Shelf using the COAWST model.
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Mendonça, Luis Felipe F., Fetter-Filho, Antônio F. H., Andrade, Mauro M., Oliveira, Fabricio S. C., Lindemann, Douglas S., Freitas, Rose Ane P., and Lentini, Carlos. A. D.
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CONTINENTAL shelf ,ATMOSPHERIC models ,SENSE data ,SEA level ,REMOTE sensing - Abstract
The Southern Brazilian Continental Shelf (SBCS) is an area with great ecological and economic importance to Brazil. In this region can be observed the recurrent passage of frontal systems and extratropical cyclones, which are more frequent during the winter months of the southern hemisphere. These systems act on the ocean surface layers as direct driving forces, which may change the thermohaline structure of the water column and induce sea level perturbations. This study used the coupled ocean atmosphere regional model (COAWST) to evaluate the effect of the passage of a frontal system associated with an extra-tropical cyclone. The ocean and atmosphere models (ROMS and WRF) was configured with two nested grids, in order to solve the dynamic processes, at different scales, that comprise the energy transfer from the atmospheric system to the ocean. The simulation was based on a study case, occurred in September 2016, on the southwestern brazilian continental shelf. The model outputs were analyzed/compared to remote sensing data and 5 tide gauges from the Agricultural Research and Rural Extension (EPAGRI) in Santa Catarina state, Brazil. This comparison showed a correlation higher than 78% between sea level rise data and the model results, with average difference of less than 25cm. The use of low-pass Lanczos-Cosine filter made it possible to identify the meteorological component in the ocean model outputs. Our simulation also presents the sea level anomalies, associated with the crossing of the atmospheric frontal system, progressing to northward along the continental shelf at 480km.day-1, probably associated with the presence of a coastal-trapped wave. [ABSTRACT FROM AUTHOR]
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- 2021
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9. IMPACTS OF SOUTHERN HEMISPHERE WESTERLIES ON THE BRAZIL CURRENT AT 30°S
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Carvalho, Jessica S., primary, Oliveira, Fabricio S. C., additional, and Campos, Edmo J. D., additional
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- 2018
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10. IMPACTS OF SOUTHERN HEMISPHERE WESTERLIES ON THE BRAZIL CURRENT AT 30°S
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Fabricio S. C. Oliveira, Jessica S. Carvalho, and Edmo J. D. Campos
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geography ,geography.geographical_feature_category ,Ocean gyre ,Westerlies ,Geomorphology ,Southern Hemisphere ,Boundary current ,Wind forcing - Abstract
Previous studies have pointed out an intensification of the global western boundary currents induced by changes in the wind-stress curl patterns over the oceans. The Brazil Current (BC) is the western boundary current into the South Atlantic Subtropical Gyre, which flows southwards along the Brazilian coast. A numerical model is used to investigate the response of BC to this change in wind forcing between 1960-2010, across 30°S. The results found here support the increasing trend noticed in the wind-stress curl and a poleward migration of the South Hemisphere westerlies in the past decades. The residual transport of BC at 30_S is composed by its southward main flow and the northward branch of a recirculation cell (Rec) east of the BC. Both the BC and Rec transports showed a decrease trend of 0.10 Sv dec1 and 0.28 Sv dec1, respectively. It suggests a southward migration of Rec in response to changes in the westerlies. The results also indicate a relative intensification in the western boundary transport and a strengthening in the South Atlantic Subtropical Gyre. Keywords: Western Boundary Current, Meridional Transport, HYCOM. RESUMO. Estudos anteriores apontam para uma intensificacao das correntes de contorno oeste globais induzidas por mudancas no rotacional do estresse do vento sobre os oceanos. A Corrente do Brasil (CB) e a corrente de contorno oeste do giro Subtropical do Atlântico Sul, que flui para sul ao longo da costa brasileira. Um modelo numerico e usado para investigar a resposta da CB as mudancas na forcante do vento entre 1960-2010, ao longo de 30_S. Os resultados encontrados aqui suportam a tendencia de aumento observada no rotacional do estresse do vento e a migracao para o polo dos ventos de oeste do hemisferio sul nas ultimas decadas. O transporte residual da CB em 30°S e composto pelo seu fluxo principal para sul e o braco para norte de uma celula de recirculacao (Rec) a leste da CB. Ambos os transportes da CB e Rec mostraram uma tendencia de reducao de 0,10 Sv dec1 e 0,28 Sv dec1, respectivamente. Isto sugere uma migracao para sul da Rec em resposta as mudancas dos ventos de oeste. Os resultados tambem indicam uma relativa intensificacao do transporte na borda oeste e um fortalecimento do giro Subtropical do Atlântico Sul. Palavras-chave: Corrente de Contorno Oeste, Transporte Meridional, HYCOM.
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- 2018
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11. The relationship between multi-sensor satellite data and Bayesian estimates for skipjack tuna catches in the South Brazil Bight
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Douglas Francisco Marcolino Gherardi, Fabricio S. C. Oliveira, and José Stech
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Skipjack tuna ,biology ,Meteorology ,Catch per unit effort ,Scatterometer ,biology.organism_classification ,Sea surface temperature ,SeaWiFS ,Climatology ,Ekman transport ,General Earth and Planetary Sciences ,Environmental science ,Satellite imagery ,Moderate-resolution imaging spectroradiometer - Abstract
In this study we tested a Bayesian model based on a conjugate gamma/Poisson pair associated with environmental variables derived from satellite data such as sea surface temperature (SST) and its derived gradient fields from Moderate Resolution Imaging Spectroradiometer (MODIS)/Terra, chlorophyll-a concentration from Sea Viewing Wide field of View Sensor (SEAWiFS)/SeaStar and surface winds and Ekman pumping from SeaWinds/Quick Scatterometer (QuikSCAT) to predict weekly catch estimates of the skipjack tuna in the South Brazil Bight. This was achieved by confronting the fishery data with model estimates and regressing the results on the satellite data. The fishery data were expressed by an index of catch per unit effort (CPUE) calculated as the weight of fish caught (in tonnes) by fishing week, and were divided into two series, called historical series (1996-1998; 2001), and validation year (2002). The output of model CPUE estimates is in good agreement with the historical weekly CPUE and generated updated weekly estimates that explained up to 62% of weekly CPUE from 2002. In general, the best proxy for the Bayesian weekly estimates is the gradient zonal SST field. The results refined previous knowledge of the influence of SST on the occurrence of skipjack tuna.
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- 2010
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12. Multitemporal assessment of the geomorphologic evolution of the Restinga of Marambaia, Rio de Janeiro, Brazil
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M. Kampel, Fabricio S. C. Oliveira, and S. Amaral
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geography ,geography.geographical_feature_category ,Visual interpretation ,Coastal zone ,Classification procedure ,General Earth and Planetary Sciences ,Shoal ,Physical geography ,Bay ,Image resolution ,Cartography ,Geology - Abstract
The Restinga of Marambaia is an emerged sand bar located between the Sepetiba Bay and the South Atlantic Ocean, on the south-east coast of Brazil. The objective of this study was to observe the geomorphologic evolution of the coastal zone of the Restinga of Marambaia using multitemporal satellite images acquired by multisensors from 1975 to 2004. The images were digitally segmented by a region growth algorithm and submitted to an unsupervised classification procedure (ISOSEG) followed by a raster edit based on visual interpretation. The image time-series showed a general trend of decrease in the total sand bar area with values varying from 80.61 km2 in 1975 to 78.15 km2 in 2004. The total area calculation based on the 1975 and 1978 Landsat MSS data was shown to be super-estimated in relation to the Landsat TM, Landsat ETM+, and CBERS-2 CCD data. These differences can also be associated to the relatively poorer spatial resolution of the MSS data, nominally 79 m, against the 20 m of the CCD data and 30 m of the TM and ETM+ data. For the estimates of the width in the central portion of the sand bar the variation was from 158 m (1975) to 100 m (2004). The formation of a spit in the northern region of the study area was visually observed. The area of the spit was estimated, with values varying from 0.82 km2 (1975) to 0.55 km2 (2004).
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- 2008
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13. Seasonal and regional variation in egg size of the Argentine anchoita (Engraulis anchoita) in the southeastern Brazilian Bight
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del Favero, Jana M., primary, Katsuragawa, Mario, additional, Oliveira, Fabricio S. C., additional, Tannure, Nayara C., additional, Zani-Teixeira, M. L., additional, and Turner, Jefferson T., additional
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- 2017
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14. Characterization of westward propagating signals in the South Atlantic from altimeter and radiometer records
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Paulo S. Polito and Fabricio S. C. Oliveira
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Baroclinity ,SENSORIAMENTO REMOTO ,Rossby wave ,Soil Science ,Geology ,Atmospheric sciences ,Physics::Geophysics ,law.invention ,Physics::Fluid Dynamics ,Sea surface temperature ,Radar altimeter ,law ,Climatology ,Middle latitudes ,Astrophysics::Earth and Planetary Astrophysics ,Altimeter ,Computers in Earth Sciences ,Thermocline ,Physics::Atmospheric and Oceanic Physics ,Geostrophic wind ,Remote sensing - Abstract
Radar altimeter data from TOPEX/Poseidon and Jason-1 and microwave radiometer data from TRMM/TMI are used to investigate the large-scale variability between 10.5°S and 35.5°S in the South Atlantic Ocean. The proposed method for the analysis of the longitude–time diagrams of the cross-correlation between SSH and SST anomalies shows that the variability in mid latitudes is a blend of first-mode baroclinic Rossby waves and propagating mesoscale eddy-like structures. The estimated phase speed of the wave (cp) and propagation speed of the eddies (cv) are similar. In 70% of the cases, the absolute difference between cp and cv is less than 11%. In 40% of the cases this difference is less than 5%. Statistical results indicate that in the case of eddies, as the thermocline deepens the sea surface temperature rises and vice-versa. However, planetary waves show more complex, yet self-consistent results. In lower latitudes (10.5°S–15.5°S), the shallower thermocline and the weak thermal gradients impose a zero phase lag between temperature and height, similar to eddies. Poleward of those latitudes, sea surface temperature and height are in quadrature of phase. This indicates that geostrophic advection of the relatively stronger thermal gradient is performed by Rossby waves.
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- 2013
15. Teor e dinâmica do carbono no solo em sistemas de integração lavoura-pecuária
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SALTON, J. C., MIELNICZUK, J., BAYER, C., FABRICIO, A. C., MACEDO, M. C. M., BROCH, D. L., JULIO CESAR SALTON, CPAO, J. MIELNICZUK, UFRGS, C. BAYER, UFRGS, A. C. FABRICIO, ENGENHEIRO AGRÔNOMO, MANUEL CLAUDIO MOTTA MACEDO, CNPGC, and D. L. BROCH, FUNDAÇÃO MS.
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pastures ,Pastagem - Published
- 2011
16. Influência de diferentes sistemas de produção sobre a população de Rotylenchulus reniformis (Linford & Oliveira, 1940) no solo
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SEREIA, A. F. R., ASMUS, G. L., FABRICIO, A. C., Aline F. R. Sereia, Universidade Federal de Mato Grosso do Sul, Guilherme Lafourcade Asmus, Embrapa Agropecuária Oeste, and Amoacy Carvalho Fabrício, Embrapa Agropecuária Oeste.
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Nematóide - Abstract
Made available in DSpace on 2015-07-23T05:26:45Z (GMT). No. of bitstreams: 1 4245co.pdf: 117142 bytes, checksum: c546a9a03e9c104ea1d330e3aff0eeee (MD5) Previous issue date: 2007-07-02
- Published
- 2007
17. Study of lobation and vascularization of the lungs of wild boar (Sus scrofa)
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V. P. Cabral, Antonio Marcos Orsi, Fabricio S. C. Oliveira, Antonio Augusto Coppi Maciel Ribeiro, and Márcia Rita Fernandes Machado
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Pathology ,medicine.medical_specialty ,Swine ,Animals, Wild ,Biology ,Pulmonary Artery ,Wild boar ,biology.animal ,medicine ,Animals ,Lung ,Left lung ,Bronchus ,General Veterinary ,General Medicine ,Left pulmonary artery ,Anatomy ,respiratory system ,Right pulmonary artery ,Lobe ,respiratory tract diseases ,medicine.anatomical_structure ,Pulmonary Veins ,SUÍNOS ,Animals, Domestic ,Caudal lobe - Abstract
The purpose of this study was to describe the anatomy of the lungs of wild boars for comparison with those of domestic swine. It was found that the right lung of the wild boar is divided into four lobes: cranial, median, caudal and accessory, whereas the left lung is divided into two lobes: cranial and caudal. In 93.4% of the cases, right pulmonary artery separates into the ascendant, descendant, median, accessory and caudal branches. In 73.3% of the cases, left pulmonary artery separates most frequently to form three branches to the cranial lobe, whereas the median lobe is generally supplied by only one arterial branch. There is a single pattern of bronchial distribution: in the right lung a tracheal bronchus leads to the cranial lobe, where it separates into the cranial and caudal bronchi and there are also bronchi to the median, caudal and accessory lobes. In the left lung, the large bronchus separates to form two branches, one of which further separates to form two branches to the cranial lobe whereas the other forms a single branch to the caudal lobe.
- Published
- 2001
18. Rotação lavoura pecuária no Sistema Plantio Direto
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SALTON, J. C., FABRICIO, A. C., HERNANI, L. C., JULIO CESAR SALTON, CPAO, A. C. FABRICIO, and LUIS CARLOS HERNANI, CNPS.
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Integração lavoura-pecuária - Published
- 2001
19. Efeito da aplicação de calcário e de doses de enxofre sobre propriedades químicas do solo, produção e composição mineral do sorgo (Sorghum bicolor (L) Moench)
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VELOSO, C. A. C., FABRICIO, A. C., DURAES, F. O. M., CARVALHO, E. J. M., CARLOS ALBERTO COSTA VELOSO, CPATU, AMOACY CARVALHO FABRICIO, CPAO, FREDERICO OZANAN MACHADO DURAES, CNPMS, and EDUARDO JORGE MAKLOUF CARVALHO, CPATU.
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Sorghum Bicolor ,Sulphur ,Soil chemicophysical properties ,Enxofre ,nutrients ,Sorgo ,liming ,Produção de matéria seca ,dry matter content ,Propriedade físico-química do solo ,Calagem ,Nutriente - Abstract
Com o proposito de comparar os efeitos da calagem e de doses crescentes de enxofre sobre as propriedades químicas de dois solos: Latossolo Vermelho Amarelo (LV) e Latossolo Vermelho escuro (LE), produção de matéria seca, teor e acumulo de N, P, K, Ca, Mg e S do sorgo granífero, procedeu-se a incubação, por 25 dias, de amostras de solo com calcário e conduziu-se um ensaio em casa de vegetação com seis doses de enxofre: 0; 10; 20; 40; 80 e 160 mg/dm1, na forma de Na2SO4. Cinquenta dias apos a semeadura, coletou-se a parte aérea das plantas e determinaram-se os teores e acúmulos de N, P, K, Ca, Mg e S. Os teores das bases trocáveis do solo aumentaram com a calagem, sendo que a saturação em bases ficou próxima a 80% nos dois solos. Os valores de pH e os teores de Ca e Mg nos tecidos de sorgo aumentaram com as adições de CaO e MgO aos solos. A produção de matéria seca do sorgo cultivado no solo LV foi superior em relação ao solo LE, e as doses crescentes de enxofre não influenciaram os teores foliares de N, P, K, Ca, Mg e S nos dois solos. Made available in DSpace on 2021-02-05T18:18:06Z (GMT). No. of bitstreams: 1 Efeito-da-aplicacao-de-calcario.pdf: 3485143 bytes, checksum: ab6ba84044ce757924ecb09a17dda577 (MD5) Previous issue date: 1997
- Published
- 1997
20. Corrigendum to 'Characterization of westward propagating signals in the South Atlantic from altimeter and radiometer records' [Remote Sens. Environ., 134: 367–376]
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Fabricio S. C. Oliveira and Paulo S. Polito
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Radiometer ,Radon transform ,Climatology ,Cross correlation analysis ,Soil Science ,Geology ,Altimeter ,Computers in Earth Sciences ,Mesoscale eddies ,Remote sensing - Published
- 2013
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21. Avaliação de higroscopicidade de fertilizantes e corretivos
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ALCARDE, J. C., MALAVOLTA, E., BORGES, A. L., MUNIZ, A. S., VELOSO, C. A., FABRICIO, A. C., VIEGAS, I. de J. M., ESALQ, CENA/USP, PÓS-GRADUANDO ESALQ/USP, CARLOS ALBERTO COSTA VELOSO, CPATU, and ISMAEL DE JESUS MATOS VIEGAS, CPATU.
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Correção ,soil ,Fertilizer ,Solo ,Higrocopicidade ,liming ,Adubo ,Higroscopicity ,Calagem - Published
- 1992
22. Sinais propagantes para oeste no oceano Atlântico: vórtices ou ondas de Rossby?
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Fabricio S. C. Oliveira, Paulo Simionatto Polito, Ricardo de Camargo, Edmo Jose Dias Campos, Ilson Carlos Almeida da Silveira, and Ronald Buss de Souza
- Abstract
A maior parte do sinal propagante para oeste nos oceanos é explicada pelas ondas de Rossby baroclínicas. Porém, vórtices de mesoescala podem interferir na identificação dessas ondas. A maior adversidade em se distinguir o sinal dessas feições é que os vórtices parecem propagar-se com uma velocidade aproximada à velocidade de fase das ondas. Um dos objetivos do presente trabalho é caracterizar os sinais propagantes para oeste em termos da sua velocidade de fase no Atlântico. A análise se baseia em de dados das anomalias da altura da superfície do mar (ASM) e da temperatura de superfície do mar (TSM) derivados dos altímetros TOPEX/Poseidon e Jason-1 e radiômetro TRMM/TMI. As anomalias de ASM e TSM foram filtradas por um conjunto de filtros de resposta impulsiva finita (FIR) para eliminar o sinais sazonais, interanuais e sinais de alta frequência. A análise de correlação cruzada entre as matrizes zonais-temporais de ASM e TSM foi feita para limitar as conclusões aos sinais presentes simultaneamente em ambas as bases de dados. A velocidade de fase das ondas de Rossby foi estimada via transformada de Radon aplicada às matrizes de correlação cruzada. Um máximo local solitário sobre a origem foi observado nos diagramas de correlação e associado à presença de vórtices de mesoescala. Porém este máximo se alonga com a mesma inclinação correspondente à velocidade de fase das ondas de Rossby. Isto sugere que estes vórtices podem propagar-se sobrepostos às ondas. As velocidades de propagação dos vórtices são estimadas através do ajuste de uma função de decaimento exponencial no tempo e na distância zonal. Análises preliminares da transformada de Fourier mostraram que os sinais propagantes para oeste são predominantemente anuais, embora picos de frequências semi-anuais são observadas nestes espectros. Em decorrência da evidência de que os sinais propagantes para oeste são compostos simultaneamente por vórtices e ondas de Rossby, um filtro baseado na transformada de Radon e sua inversa foi desenvolvido para separar o sinal de feições com simetria circular. O filtro de vórtice circular foi aplicado em três áreas onde se localizam a Corrente das Agulhas, Confluências Brasil-Malvinas e Corrente do Golfo. Com base na análise visual pode-se afirmar que o filtro identificou com sucesso vórtices circulares nas três áreas estudadas, tanto nos dados de ASM como nos de TSM. As velocidades de fase das ondas de Rossby foram ligeiramente mais rápidas, em média, que as velocidades dos vórtices em todas as três áreas, cerca de 10% na ASM e 13% na TSM. As velocidades calculadas após a aplicação do filtro de vórtice circular apresentaram um viés positivo em relação as obtidas via correlações cruzadas. A maior diferença na estimativa das velocidades dos vórtices foi de 21% e nas ondas 25%, ambas na região da Corrente das Agulhas. Baseado nas evidências apresentadas é possível afirmar que vórtices podem se propagar com velocidades semelhantes à velocidade das ondas de Rossby do primeiro modo baroclínico. O lag das correlações cruzadas indicaram que o processo físico que relaciona a variabilidade nos dados de ASM à dos TSM é a advecção causada pela passagem de uma onda planet´aria do primeiro modo baroclínico. Esta advecção pode ser horizontal ou vertical dependendo do processo dominante que ocorre numa dada região. In the oceans, most of the westward propagating signal is explained by baroclinic Rossby waves. However, mesoscale vortices can interfere in the identification of these waves. The main observational issue is to distinguish eddies from the wave-like propagating signals, since the former propagates with a speed that approximately matches the phase speed of baroclinic Rossby waves. The objective of the present study is to characterize the westward propagating signals in terms of their propagation speeds in the Atlantic. The analysis is based on satellite derived sea surface height (SSH) and sea surface temperature (SST) anomalies from the TOPEX/Poseidon and Jason-1 altimeters and TRMM/TMI radiometer records. The SSH and SST anomaly maps were filtered with a set of finite impulse response filters to eliminate the seasonal and interannual cycles and high frequency signals. The cross-correlation analysis between SSH and SST longitude-time matrices was performed to limit the conclusions to the features that appear simultaneously in both datasets. The of Rossby wave phase speed was estimated via Radon transform applied to the longitude-time cross-correlation matrices. A single local maximum was was observed at the origin of the cross-correlation diagrams and associated to mesoscale vortices. However, this maximum spreads along the same slope that characterizes the the westward Rossby wave phase speed. This suggests that vortices propagate superimposed to Rossby waves. The propagating speed of the vortices is estimated from the linear fit of an exponential decay function. A preliminary Fourier analysis show that the westward propagating signals are predominantly annual, yet peaks in the semiannual frequencies are observed. The evidence that the westward propagating signals are composed simultaneously of vortices and Rossby waves motivated the development of a filter based in the Radon transform and its inverse, to isolate the signal associated to circularly symmetric features. This circular vortex filter was applied in three areas that portray the Agulhas Current, the Brazil-Malvinas Confluence, and the Gulf Stream. Based on visual analysis one can affirm that the circular filter sucessfully identified vortices in three areas, both in the SSH and in the SST data. The phase speeds of Rossby waves were, on average, slightly faster than vortices speeds in the three areas, approximately 10% in SSH and 13% in SST. The speeds calculated after the circular vortex filter was applied presented a positive bias in relation to those obtain from cross correlations. The largest difference in the vortices speeds was 21% and in the wave speeds 25%, both in Agulhas Current region. Based on the present evidences it is possible to state that vortices can propagate with speeds similar to those of first-mode baroclinic Rossby waves. The cross-correlation lag suggests that the physical process that links the variability of the SSH to that of the SST is the advection generated by the passage of a first-mode baroclinic planetary wave. This advection can be horizontal or vertical depending of the dominant process in a given region.
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