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1
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DOUGLAS LEONARDO SALES PEDROSA
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ANALYSIS OF FLOW EXTREMES IN THE MUNDAÚ RIVER AND ASSOCIATED SYNOTIC SYSTEMS IN THE PERIOD FROM 1990 TO 2019
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Leader : RICARDO FERREIRA CARLOS DE AMORIM
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MEMBRES DE LA BANQUE :
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MARIA LUCIENE DIAS DE MELO
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MIKAEL TIMÓTEO RODRIGUES
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RANIERI CARLOS FERREIRA AMORIM
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RICARDO FERREIRA CARLOS DE AMORIM
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Data: 21 févr. 2022
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Afficher le Résumé
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This study aimed to analyze extreme flow events in the Mundaú River and identify the synoptic scale systems that directly influenced these cases, between the years 1990 to 2019. For this analysis, daily flow data from the Agência Nacional de Águas (ANA) for four fluviometric stations located in the cities of Murici; Rio Largo; Santana do Mundaú and União dos Palmares, and with these data the percentile technique was applied, and then a value equal to or greater than the 95th percentile was considered an extreme flow event. With these values, 19 cases were identified where the flow was considered extreme in at least one fluviometric station. Soon after, the systems that acted in the region of the River Mundaú Watershed (RMW) were identified, through the data of the ECMWF model in 10 levels of the atmosphere and satellite images. The year 2000 was the year with the highest number of occurrences of extreme flow (03), which represents 16% of the total. Dividing the three decades, from 1990 to 1999 it concentrated 31.5% of the events, from 2000 to 2009, 52.5%, and from 2010 to 2019, 16%. Extreme flow events in the Mundaú River had a concentrated distribution between the months of autumn and winter, with the months of June (9) and August (4) showing the highest number of cases within the series. As for the systems that were identified, 15 cases with Wave Disturbance of Trades Winds (WDTW); 2 with Upper Tropospheric Cyclonic Vortices (UTCV) and 2 with Tropical Waves (TW).
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2
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KECIA MARIA DA SILVA
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Climatology of Sea and Land Breezes in the State of Alagoas
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Leader : HELBER BARROS GOMES
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MEMBRES DE LA BANQUE :
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DIRCEU LUÍS HERDIES
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FABRICIO DANIEL DOS SANTOS SILVA
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HELBER BARROS GOMES
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HENRIQUE MELO JORGE BARBOSA
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Data: 25 févr. 2022
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Afficher le Résumé
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The breeze is an important factor in explaining the diurnal wind cycle in coastal regions, which, in turn, implies the advection of weather conditions from the sea to the land surface and vice versa. In the NEB region (Northeast Brazil) the winds are controlled by the circulation of trade winds and breezes. The magnitude of the large-scale wind flow, whether parallel or perpendicular to the orientation of the coast, where the differential heating between land and sea occurs, is decisive for the potential of breezes formation and their penetration into the continental interior. Some studies were carried out at NEB on the interaction of breezes with other systems, such as complex topographic systems, synoptic-scale wind, analysis of local precipitation variation and analysis of the territorial extent of the breeze. However, in Alagoas, there are few records of studies on breezes. In this sense, daily, seasonal and annual climatologies were used to analyze the diurnal cycle of breezes in this work, through surface meteorological observations from INMET (National Institute of Meteorology) stations in Alagoas, as well as data from the fifth generation of reanalysis surface from the European Center for Medium-Range Weather Forecasts (ECMWF), ERA5-Land. The ERA5-Land reanalysis was validated for Alagoas having as reference the 7 INMET surface stations. From these data, the comparative climatologies of the variables were generated: air temperature, surface pressure, relative humidity, precipitation, wind direction and speed in a period of 11 years, from mid-2008 to December 2019. The temperature and pressure were corrected with a bias of up to 0.7°C and 11.93 hPa and an RMSE of 0.34°C and 11.9 hPa. For the analysis of the breezes, the same meteorological parameters were used, except for precipitation, through the method of simultaneous alteration of the variables, to detect frontogenesis times. There were 450 days with breezes (average of detections for the 7 seasons) in the study period, being 21.42% in winter and 28.33% in summer, with maximum front development starting at 17h UTC and predominance of 28% of cases in March and April. It was observed that the closer to the coast, the sooner the formation of the FBM (Maritime Breeze Front) begins. It was also observed that the sea breeze has a significant potential to lower the temperature and increase the local relative humidity during the afternoon, as also seen in other studies. The results show the influence of breezes on the local climate, affecting thermal comfort, providing moisture to the atmosphere
on the dispersion of pollutants etc., and indicates the need for representative wind reanalysis for regional and local scale, in order to spatially broaden the understanding of this system, in which there is a lack of observation data.
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3
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JÉSSICA DE LIMA SANTOS
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Study of the impact of aerosols on the optical thickness of the atmosphere in the northeast region of brazil.
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Leader : GLAUBER LOPES MARIANO
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MEMBRES DE LA BANQUE :
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GLAUBER LOPES MARIANO
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HELBER BARROS GOMES
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HELIOFABIO BARROS GOMES
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WENDELL RONDINELLI GOMES FARIAS
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Data: 25 févr. 2022
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Afficher le Résumé
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A poluição atmosférica é um dos principais problemas ambientais atualmente nas grandes e médias cidades. Os aerossóis atmosféricos são um dos principais responsáveis pela poluição atmosférica por todo mundo. E tem extrema relevância pois afetam fortemente o balanço de radiativo ao interagir com a radiação solar, o clima, a química da atmosfera, a visibilidade, além de serem altamente prejudiciais à saúde humana expostas às altas concentrações de partículas, desde a escala local até a escala regional e global. As partículas de aerossóis possuem características ópticas no qual é possível quantificar os seus efeitos causados na atmosfera, bem como saber qual é o seu tipo, sendo altamente importante essas características ópticas. Uma das formas de se estudar estas características e/ou propriedades dos aerossóis é através da análise da EOA (espessura óptica dos aerossóis) que quantifica a atenuação da radiação em um meio contendo material opticamente ativo. Sendo assim o presente estudo pretende avaliar o comportamento da EOA sobre a Região Nordeste do Brasil, analisando o seu comportamento médio para o período dos anos de 2005 a 2019. Os dados foram coletados pelo sensor OMI (Ozone monitoring Instrument) da NASA (National Aeronautics and Space Administration) a bordo do satélite Aura com resolução espacial de 1° x 1° e resolução temporal diária. A partir destes dados utilizados foram realizadas as médias e percentis (P99) para saber dentro da área de estudo quais foram os locais que apresentaram os máximos valores de EOA e em quais períodos específicos. Após as análises os resultados mostraram que a variável de aerossóis do sensor possui um comportamento sazonal onde observamos altos valores nos 3 primeiros meses (janeiro, fevereiro e março), os valores vão diminuindo nos próximos 3 meses (abril, maio e junho) e voltam a aumentar nos meses de julho, agosto e tem seus maiores valores a partir do mês de setembro com seu pico máximo ficando entre o mês de setembro e outubro em quase todos os anos analisados.
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4
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DANIEL MILANO COSTA DE LIMA
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EVALUATION OF THE IMPACT OF THE SOUTHERN NIÑO-OSCILATION AND SOUTHERN ANNULAR MODE VARIABILITY MODES ON OZONE CONCETRATIONS OVER THE SOUTHERN HEMISPHERE
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Leader : GLAUBER LOPES MARIANO
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MEMBRES DE LA BANQUE :
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ERICKA VOSS CHAGAS
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FABRICIO DANIEL DOS SANTOS SILVA
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GLAUBER LOPES MARIANO
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LUCAS VAZ PERES
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MATEUS DIAS NUNES
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Data: 4 mars 2022
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Afficher le Résumé
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Ozone is a gas present in the Earth's atmosphere in small amounts that contributes significantly to the energy balance of the atmosphere. Several factors can affect its concentration and distribution, such as the El Niño - Southern Oscillation (ENSO) and Southern Annular Mode (SAM) variability modes. In this study, climatological analyzes and analyzes for periods with ENSO and SAM action were performed using a robust series of Total Ozone Column (TOC) data from the Multi-sensor reanalysis (MSR) product, made available by the European Center for Medium-Range Weather Forecasts (ECMWF), for the area of the southern hemisphere, spanning a period of 41 years (1980-2020). TOC’s means, anomalies when under the action of variability modes and statistical analysis of the dominant variability patterns were obtained. The TOC's climatological quarterly behavior agrees with the results of previous studies. When there is El Niño action, the accentuated transport of Brewer-Dobson Circulation (BDC) causes positive anomalies at higher latitudes and negative anomalies at low latitudes. During La Niña the inverse is observed. In the study for the action of the positive phase of the SAM, in agreement with previous studies and with the theoretical behavior of the SAM, a predominance of negative anomalies in high and medium latitudes is observed. In the action of the positive phase of the SAM, a predominance of negative anomalies in high and medium latitudes and positive anomalies in low latitudes is observed. The inverse is observed for the negative phase. Statistical analyzes show that the patterns of greatest influence on TOC in DJF, MAM and JJA are SAM and BDC ozone transport. The polar vortex and the ozone “croissant” are the dominant patterns in SON. Trends of increase in the frequency of SAM positive phase and the increase in the average concentration of the TOC within the polar vortex in the spring months are observed, which may be linked to the climatic changes that occurred within the study period.
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5
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IAGO JOSE DE LIMA SILVA
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WET AND DRY PERIODS IN THE STATE OF ALAGOAS VIA DROUGHT INDEX.
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Leader : JOSE FRANCISCO DE OLIVEIRA JUNIOR
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MEMBRES DE LA BANQUE :
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CLAUDIO JOSÉ CAVALCANTE BLANCO
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GIVANILDO DE GOIS
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HELIOFABIO BARROS GOMES
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JOSE FRANCISCO DE OLIVEIRA JUNIOR
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JOSICLEIA PEREIRA ROGERIO
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Data: 20 avr. 2022
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Afficher le Résumé
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The state of success of the rains has its economic basis for agriculture, and the knowledge of the rainy seasons and the success of agricultural enterprises is fundamental. The objective was to define the rainy and dry periods in the state of Alagoas through multivariate analysis applied to the Standardized Precipitation Index (SPI). Use of rainfall data and filled in (period of 54 stations not filled in) (1900 data filled in by default2016) via multiple imputation method, filled in and valid2, where they will be filled out2; R2=0.65; R2= =54.85 mm; RQEM=54.84 mm), Agreste (r=0.69; R2=0.47; EPE=70.97 mm; RQEM=70.97 mm) and East (r=0.61; R2=0.37 ; EPE=154.87 mm; RQEM=109.48 mm). Cluster analysis was applied to time series (definition of periods1) and SPI-2 (annual determination of droughts and rainfall). The accumulated annual rainfall presented two distinct periods: 1960 to 1990 (P1) and 1990 to 2016 (P2), according to the Pettitt test. Both periods alternate according to the phases of La Niña and Neutral (rainy years) and El Niño (dry years). In terms of monthly fees, only the eastern part of Alagoas has the rainy months in the historical series. Of the connection methods tested, the average connection, also known as C which believes that it proves to be cophenetic 0.8760) represents or characterizes homogeneous regions of groups, one non-coastal1 (G and two others further inland2), and two non-homogeneous groups (NA) in the state. The SPI assigned to the annual El to identify the independent and wet periods, in the Niño-Oscillation (ENSO) categorization. As categories of the annual SPI12 high variability and decadal presented us, except as extremely dry and wet groups. There is greater variability in the dry and rainy periods near the coast than in the interior of the state.
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6
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VALTER RAMOS DE SOUSA FILHO
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Dynamics of Hotspots in the Climatic Mesoregions of the state of alagoas
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Leader : JOSE FRANCISCO DE OLIVEIRA JUNIOR
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MEMBRES DE LA BANQUE :
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DAVID MENDES
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GIVANILDO DE GOIS
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JOSE FRANCISCO DE OLIVEIRA JUNIOR
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MARIA LUCIENE DIAS DE MELO
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Data: 20 avr. 2022
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Afficher le Résumé
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This study evaluated the spatiotemporal variability of fire focis (FF) in the three climatic mesoregions of Alagoas: Arid Zone, East and Hinterland Alagoano. FF data were obtained from the Queimadas Database (BDQueimadas) between 1998-2020. The FF time series was submitted to descriptive, exploratory, and multivariate statistical analysis applied to 102 municipalities in Alagoas. Based on the hierarchical grouping, three homogeneous groups were identified (G1, G2 and G3) in the Arid Zone and two homogeneous groups of FF in the Hinterland and East Alagoas (G1 and G2). Some municipalities did not form groups (NA), such as: Belo Monte (26.83 ± 25.87 foci), Limoeiro de Anadia (54.48 ± 38.65), Penedo (262.83 ± 183.80 foci) and Coruripe (553 ± 369.40 foci). The interannual FF variability in Alagoas is associated with agricultural activities, deforestation, new areas for animal husbandry and sugarcane harvest. In the spatial evaluation via FF density per municipality, the total period (1998-2020) and the years highlighted in the time series (2012 and 2019) were used. The highest FF density record in the total period is found in the East Alagoas mesoregion and it is not ruled out that the highlighted years are influenced by the occurrence of drought and dry periods in Alagoas. The Atlantic Forest biome is more threatened according to the number of records of annual hotspots, however, in some years there is an increase in the Caatinga biome.
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7
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IARA BEZERRA DA SILVA CAVALCANTE
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ANALYSIS OF SPATIAL-TEMPORAL VARIABILITY OF PRECIPITATION IN MACEIÓ-AL AND ITS CLIMATE CAUSES
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Leader : DJANE FONSECA DA SILVA
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MEMBRES DE LA BANQUE :
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DJANE FONSECA DA SILVA
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FABRICIO DANIEL DOS SANTOS SILVA
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OSMAR EVANDRO TOLEDO BONFIM
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Data: 6 mai 2022
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Afficher le Résumé
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Due to the pluviometric behavior in the city of Maceió, the general objective of this work is to analyze the spatial and temporal variability of precipitation in Maceió, identifying homogeneous areas and, consequently, identifying the climatic cause for the occurrence of its variability and its extremes. . Precipitation data from Maceió were used for 13 meteorological stations, with periods from 2015 to 2020, obtained from the Municipal Civil Defense, with no failures in the study period. Through spatialization, it was observed that the mean annual Standardized Precipitation Index (SPI) values were classified as normal. However, the upper part of the capital, to the north, and the North Coast of Maceió have lower values that are closer to events classified as dry, unlike the lower part and South Coast, which have SPI closer to rainy events. For the SPI mean, two regions (R1 and R2) were identified, separated into groups by cluster analysis, which showed greater Euclidean distance and less similarity. The BoxPlot graph presents similar values in both the upper limit and the median for both regions (R1 and R2), in which the SPI of the upper value for the two regions has a maximum value of approximately 2.99, whereas the lower limit has a SPI close to to 1.1 for R1 and 1 for R2. In the Mann-Kendall trend, trends of decreasing precipitation were identified in region 1, and a slight increase in the trend of precipitation in region 2, both regions showed statistical significance through the T-Student test. Using wavelet analysis, the following scales were identified for region 1: seasonal, semiannual, interannual, ENOS, extended ENSO, Sunspots and Atlantic Dipole, in which ENOS and extended ENSO presented dominant scale, whereas for region 2, they were The following scales were identified: seasonal, semiannual, interannual, ENSO, Sunspots and Atlantic Dipole, with ENSO as the dominant scale. With the use of the cross wavelet, local managers can predict droughts after the occurrence of maximum IOS and that extreme events in Maceió have a significant relationship with ENSO. It is concluded that, through the statistical analysis used, it was possible to identify the temporal and spatial variability of precipitation in the capital of Alagoas.
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8
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MARIA JOSE DA SILVA LIMA
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ANALYSIS OF CLIMATE CAUSES ON THE NUCLEI OF BRAZILIAN DESERTIFICATION
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Leader : DJANE FONSECA DA SILVA
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MEMBRES DE LA BANQUE :
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DJANE FONSECA DA SILVA
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JORIO BEZERRA CABRAL JUNIOR
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MARIA LUCIENE DIAS DE MELO
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Data: 13 mai 2022
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Afficher le Résumé
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Desertification is a process of degrading soil modifications, leading to desert aspects, as a result of climatic variations and anthropic activities. This study has the general objective to study the possible climatic causes that influence the desertification process in the existing desertification nuclei in the Brazil. Precipitation and temperature data from the cities that make up the the Desertification Nuclei in Brazil, coming from the National Water Agency, the National Institute of Meteorology and Ceará Foundation for Meteorology and Resources Water for the period 1981 to 2020 for Irauçuba, 1961 to 2019 for Cabrobó, 1971 to 2019 for Gilbués and 1989 to 2019 for Seridó. We also used data from Atlantic Dipole, Southern Oscillation Index, Pacific Interdecadal Oscillation, Pacific Decennial Oscillation and Atlantic Multidecennial Oscillation obtained from Earth System Research Laboratory/National Oceanic and Atmospheric Administration. It was observed that the frequency of dry years was higher than that of wet years, according to the IAC in Irauçuba, the year 2000 became a turning point in the distribution of local rainfall. For Cabrobó and Seridó, the IAC recorded more occurrences of years wet years than dry years, however, dry events were more frequent and were more intense, and in some of these years there was the performance of the El Niño phenomenon. In the center of Gilbués the dry and wet years occurred practically in the same proportion. Decreasing trends were detected in the core precipitation indicating that rainfall has decreased over time, while in the temperature series an increasing trend was pointed out. The analyses of Ondaleta showed influence of different time scales on the series of precipitation and core temperature, and these scales are responsible for increases anomalous in the series, when acting simultaneously. The time scales that most influence the Irauçuba precipitation series are: the seasonal scale, the scale from 4 to 8 years, the 11-year scale. Cabrobó was influenced by the seasonal scale, the scale of 2 to 4 years, the 11-year scale. The Seridó precipitation series is influenced by the seasonal scale, from 2 to 4 years and 7 years. The presence of the seasonal scale was observed in the precipitation series of Gilbués, the time scale of 2 to 4 years, coinciding with the period of operation of the scale of 11 and the scale of 16 years. The crossed Wavelet showed interrelationships between the precipitation series of the nuclei and the series of climatic indices of the scales dominants of each nucleus. The maximum precipitation in the Irauçuba core occurs 3 years before the maximum occurrence of the Atlantic Dipole. For Cabrobó, the maximum Precipitation occurs 27 to 54 months before the Atlantic Dipole maximum. In Seridó the maximum precipitation occurs 33 months after the maximum of the IOS. For Gilbués, the coherence suggests that the maximum peak of precipitation in the locality occurs 72 months before the Atlantic Dipole maximum.
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9
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IRIS LAYANNE NOBRE FRANCA
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EFFECT OF CLIMATE VARIABILITY ON LOW LEVELS OF RESERVOIRS IN THE SÃO FRANCISCO RIVER HYDROGRAPHIC BASIN
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Leader : DJANE FONSECA DA SILVA
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MEMBRES DE LA BANQUE :
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DJANE FONSECA DA SILVA
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HENRIQUE RAVI ROCHA DE CARVALHO ALMEIDA
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MARIA LUCIENE DIAS DE MELO
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Data: 22 juin 2022
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Afficher le Résumé
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The number of occurrences of extreme precipitation events has increased over the last few years, occurring, in some cases, with greater intensity and duration, thus favoring natural disasters such as severe droughts. Therefore, the expansion of knowledge about the quantity/frequency of rain that falls in a region is fundamental for the strategic planning of local and regional water resources. In this context, this research aims to analyze the level of the main reservoirs of the four sub-basins that make up the São Francisco River Basin, identifying rainfall events, particularly drought, and their possible climatic causes. The study was carried out with precipitation and quota data from four pluviometric and four fluviometric stations, respectively, representative for each variable, obtained through the National Water Agency (ANA) for the period from 1968 to 2020. Extreme drought events were classified and characterized by the standardized precipitation index (SPI), in addition to identifying years of greater precipitation deficits. The Mann-Kendall test was used to detect climatic trends in rainfall series in the four sub-regions of the BHSF and were statistically analyzed using the Student's T test. Of the four sub-regions, three of them show a downward trend in precipitation and quota, while only one shows an increase trend, highlighting the possible changes in the sub-regions' reservoir levels. Ondaletas analysis was used with the intention of verifying extreme rainfall cycles and their causes through the temporal scales observed in the precipitation series of the BHSF sub-regions. Preliminary results show that all sub-regions have higher occurrences of droughts than rains, however, extreme drought events are infrequent, whereas mild drought events were more recurrent. The years characterized as almost normal, that is, with values close to the average rainfall for the region, were the ones with the highest number in the four sub-regions, however, in all of them, the mild drought episodes had significant percentages. To identify possible climatic causes, Wavelet Analysis was used. It was found that the seasonal and interannual scales dominated, associated with the persistent El Niño Southern Oscillation sign (7 years). With information on the influence of temporal cycles on precipitation in the BHSF sub-regions, it is possible to visualize the impact of climatic phenomena on the water reserve of the Basin. In relation to the annual averages, two major climatic groups were formed that are indirectly similar to each other.
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10
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EWERTON HALLAN DE LIMA SILVA
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Agro-climatic zoning and soybean yield potential in the SEALBA region
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Leader : FABRICIO DANIEL DOS SANTOS SILVA
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MEMBRES DE LA BANQUE :
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FABRICIO DANIEL DOS SANTOS SILVA
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HELIOFABIO BARROS GOMES
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JORIO BEZERRA CABRAL JUNIOR
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ROSIBERTO SALUSTIANO DA SILVA JUNIOR
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Data: 19 août 2022
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Afficher le Résumé
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Since the early 2000s, Brazil has been one of the main grain producers worldwide, with agribusiness accounting for about 28% of Brazilian GDP by 2021. A new agricultural frontier emerges in Brazil, known as SEALBA and referring to three states located in the Northeast Brazil: Sergipe, Alagoas and Bahia. This is an extensive area with a favorable climate for the production of grains, including soybeans. Considering that the rainfall is the main climatic factor for farming, the lack of meteorological stations in the SEALBA region represents an impairment for an accurate assessment of its farming potential. Therefore, a performance evaluation of four different precipitation databases from alternative sources was carried out for observation: Two grade analysis, MERGE and CHIRPS, and two ECMWF reanalysis, ERA5 and ERA5Land. As all databases provide up-to-date data, they will serve as input for the agrometeorological model for water deficit to determine the planting periods for soybean cultivation, providing a sowing calendar aiming to minimize the possible losses caused by water deficiencies. As a result, the SEALBA region has ideal climatic conditions for grain production, especially for soybean, whose most favorable period for cultivation is from February to June, with emphasis on the month of April with estimated potential production above 90%. It is also concluded that the northern Alagoas subareas have a larger cultivation period, followed by the coastal subareas, which the beginning of the rainy season occurs in late December to early January, providing a wider period for grain cultivation.
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11
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LOURDES GABRIELA VIEIRA BATISTA
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Analysis of the fog formation process at the airports of Manaus-AM
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Leader : NATALIA FEDOROVA
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MEMBRES DE LA BANQUE :
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CLEBER SOUZA CORREA
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MARIA LUCIENE DIAS DE MELO
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NATALIA FEDOROVA
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ROSA MARIA NASCIMENTO DOS SANTOS
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VLADIMIR LEVIT
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Data: 31 août 2022
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Afficher le Résumé
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Analyzing the fog formation processes in Manaus-AM and creating an operational forecasting model are the main purposes of this work. The frequency of fog occurrence in Manaus and the paucity of publications on the phenomenon in the northern region of Brazil motivated the study of the causes and local influences in fog formation process. From the 10 years of data, 30 most intense events were selected for the dry and rainy seasons. The analysis consisted of: (1) Analysis of surface variables (Air temperature at 2m (T), Dew Point Temperature (Td), Relative Humidity (RH), wind direction and speed, and precipitation), (2) Thermodynamic analysis (Vertical temperature and humidity profiles constructed by reanalysis data) and (3) Synoptic Analysis (Streamline, divergence and omega fields constructed by the reanalysis data). The PAFOG model was also used to evaluate its applicability for the Northern region. The observed results did not show significant differences between the dry and rainy seasons. In both seasons the average temperature was 23°C; T-TD between 0 and 2°C, wind direction between 220 and 50° and wind speed between 00 and 03KT. There was precipitation preceding the event in most cases. In Ponta Pelada, the surface variables analyzed individually, are consistent with a scenario less favorable to formations, but the average conditions showed high relative humidity (between 94 and 100$\%$) and T-TD between 1 and 2°C. Wind direction was the variable that most diverged between airports. Although the speed was weak (<3 knots) for all cases analyzed, the predominant direction in Eduardo Gomes, in all stations, was north-northwest, while in Ponta Pelada it was not possible to determine the predominance, due to variations observed. The thermodynamic profiles showed that fogs in Manaus are formed under the next conditions: 1- conditionally unstable atmosphere; 2 - weak or no inversion; 3 - wet layer up to 900hPa. The active synoptic systems that influenced fog formations during the rainy season were Upper Tropospheric Cyclonic Vortex, Bolivian High and Trough at the high level in the northeast region. During the dry season, there was influence of anticyclones and ridges in the North, Northeast and Midwest, in addition to the systems of the northern hemisphere. The predictability of the PAFOG model was considered satisfactory for all cases analyzed and the forecast was classified as good/excellent. The results allowed the construction of an operational model with favorable conditions for fog formation in Manaus in observational, synoptic, and thermodynamic aspects. This model is important to help forecast and mitigate the impact of fog on the operational sector and can be used as a starting point for improvement and creation of new forecasting methods for the northern region.
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12
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MATHEUS HENRIQUE DE FREITAS LEITE
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INFLUENCE OF GLOBAL JET STREAMS ON JET FORMATION IN NORTHEASTERN BRAZIL
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Leader : NATALIA FEDOROVA
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MEMBRES DE LA BANQUE :
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NATALIA FEDOROVA
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HELIOFABIO BARROS GOMES
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HENRIQUE FUCHS BUENO REPINALDO
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Data: 5 sept. 2022
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The Brazilian Northeast jet stream (CJNEB), internationally recognized in 2017, is located between 0ºS and 20ºS with a speed greater than 20m/s. CJNEB is a mechanism of interaction and circulation between the hemispheres, but they are still poorly studied. The aim of this study is to analyze and classify how global circulation behave during interaction with CJNEB. Three study areas were used: area I includes AS (70ºN - 70ºS and 0-90ºW); Areas 2 and 3 encompass the entire planet between latitudes 70-30oS to 70-30oN for two hemispheres, respectively. The data used for the years 2018 to 2020 were: 1) NCEP/NCAR reanalysis data, with horizontal resolution of 2.5 ºx2.5º and 17 pressure levels (between 1000hPa - 100hPa); 2) satellite images gridded in the infrared and water vapor channels of the GIBBS (Global ISCCP B1). CJNEB was identified by its location and winds velocity above 20 m/s at the 200 hPa level. The events of inter-hemispheric linkages were chosen: (a) through advancement of the CJSTHN to latitudes 0-5ºN and (b) the existence of the link with the CJNEB. There was a total of 671 occurrences of advances (a), which resulted in 266 occurrences of connections (b). Connections lasting one and more days (16 events) were analyzed in detail from formation to dissipation. These events were classified as Complete (LC) and Incomplete (LI) Bindings: 1) when CJSTHN (CJSTHS) together with CJNEB enters HS (HN) but does not join CJSTHS (CJSTHN) (LI) and 2) when CJSTHN (CJSTHS) with CJNEB enters HS (HN) and joins with CJSTHS (CJSTHN) (LC). North’s incomplete bindings (14 events) are the most common with a duration of 1 to 13 days. Zonal and meridional processes were identified by 1) number of geopotential height anomaly nuclei (nuclei) and 2) families of baroclinic cyclones in satellite images (families). The shape of the H N current has always been meridional and the HS has generally changed from zonal to meridional. The number of nuclei/families is 5/6 in the HS while in the HN they can reach 6/7, that is, the southern circulation in the HN was more intense than in the HS. Upper Tropospheric Cyclonic Vortex and Trough of Bolivian High had a strong influence on the interhemispheric connection. Conceptual models, which show the conditions for the interhemispheric connection, were elaborated. These results will be used in operational practice to forecast meridional processes influenced by the circulation from HN to HS.
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