Publications by authors named "Rita de Cassia M Alves"

Under two detection schemes, this study analyzes one of the most destructive weather systems - the explosive cyclones - in the South Atlantic, from 2010 to 2020. Then, two methods are presented to study these systems: the Observational Method (OBSM) and the Automated Method (AUTM). The first uses visual analysis of the mean sea level pressure (mslp) fields and functions to identify the local minimums using the Grid Analysis and Display (GrADS) software.

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This study aimed to classify the homogeneous regions of vegetation cover, which occur in Rio Grande do Sul, formed by clustering of pixels with same pattern of temporal variability of the Normalized Difference Vegetation Index (NDVI) of AVHRR GIMMS and MODIS series and to compare their temporal dynamics. We use K means cluster analysis for defining homogeneous regions, based on the temporal variability of GIMMS (8 km spatial resolution) and MODIS (1 km spatial resolution) NDVI data sets, using monthly images mean from 2000 to 2008 (overlapping period); and we analyzed the annual pattern of NDVI. Accuracy assessment was done with Landsat images.

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Six events of explosive cyclogenesis occurred in the south Atlantic were compared using reanalysis data and satellite water vapor imagery. Cases of different intensities (weak, moderate and strong) occurred during 2014 summer season and 2012 winter season were studied. Despite the similarities the tropopause anomaly was more prominent and vertical movements were stronger in the strong cyclogenesis cases.

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Energetic complementarity is a subject that has been concentrating more and more attention of the researchers around the world in the last years, a concept that can be applied both in energy planning and in operation of energy systems based on renewable energy resources. Spatial complementarity is the energetic complementarity evaluated between two renewable resources in different locations and, as well as the complementarity evaluated between resources in the same location, has three components: time-complementarity, energy-complementarity and amplitude-complementarity. At the same site, however, complementarity assessment can involve multiple resources simultaneously, and the study of these circumstances requires appropriate tools to handle such information.

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