Navegando por Autor "MOTA, Maria Aurora Santos da"

Agora exibindo 1 - 7 de 7

Acesso aberto (Open Access)
Avaliação de características dos regimes de umidade na flona de Caxiuanã-PA durante o experimento COBRA-PARÁ
(2010-03) TANAKA, Ludmila Monteiro da Silva; SÁ, Leonardo Deane de Abreu; MOTA, Maria Aurora Santos da
We investigate the validity of a method of humidity regimes classification, based on different "states" characterization of the Tropical Atmospheric Boundary Layer (TABL), above a forest area, according to the methodology proposed by Mahrt (1991). To perform this investigation we used radiosonde information and micrometeorological tower data collected during the drier season of the region, during the experiment "COBRA-PARÁ" (carried out from 30/10 to 15/11, 2006). The analysis of moisture regimes is based on the "phase space" data representation, where the Bowen ratio (β) is plotted against the -h/L parameter (where h is the height of the turbulent mixing layer and L is the Obukhov length scale). According to the location of the data value in this "phase space" it was possible to identify the following classes: Class I - dry air and unstable conditions, Class II - dry wind, Class III - wet wind, Class IV - wet air and unstable conditions, Class V - occurrence of water condensation on the surface, Class VI - stable conditions predominance and Class VII - dew formation generated by nocturnal radiative losses with surface cooling. Among the mentioned classes, the III, IV and VI were the most frequently observed at Caxiuanã.
Acesso aberto (Open Access)
Classificação climatológica da energia potencial disponível para a convecção na cidade de Belém-PA
(Universidade Federal do Pará, 2014-12) SANTOS, Josiane Sarmento dos; MOTA, Maria Aurora Santos da; ROCHA, Edson José Paulino da
The climatological classification of the Convection Available Potential Energy (CAPE) was studied in order to verify both the possibility of convection to start and the organizational type, in Belém (Pará - PA, Brazil), associating it to extreme precipitation events (EEPRP). For the CAPE analysis, DTCEA's radiosonde data and precipitation measurements from the INMET's stations, in the period from 1987 to 2011, we used. It was observed that the local atmosphere presented favorable conditions for the development of deep convection, because the most frequent CAPE values were higher than 1000 J/Kg, representing 61% of all radiosonde measurements. According to some authors, a CAPE value of 1000J/Kg is the deep convection limit. The CAPE 2 and 3 classifications presented significant increasing tendencies along the years, whereas CAPE 1 showed a decrease. This is probably due to the air temperature increased at the city, impacting the CAPE value. A low correlation between CAPE and EEPRP, as well as between CAPE and Pacific Ocean Index and the Atlantic Interhemispheric Gradient. was also shown. Therefore CAPE is not sufficient condition for the formation of clouds and precipitation, since meso and large scale dynamical forcing are relevant contributors to the climate modulation on the city.
Acesso aberto (Open Access)
Condições termodinâmicas de eventos de precipitação extrema em Belém-PA durante a estação chuvosa
(2012-07) TAVARES, João Paulo Nardin; MOTA, Maria Aurora Santos da
The thermodynamic conditions from any region are very important to the development of the deep, moist convection, mainly in the tropical region. Therefore, the aim of this work was to understand and characterize the role of atmospheric thermodynamic conditions during extreme rainfall events in the rainy season, in Belém (PA, Brazil). The results show that the extreme rainfall, in their majority (56%) present a pre-storm environment with strong instability, indicated by the CAPE high values (above 1000 J/kg) and meaningful values of the instability indexes. There was, however, events with low values of CAPE in the 1200 UTC sounding at the day of the event, but larger values in the day before, which indicates that the rain in question may have begun in the early hours and have last for several hours, crossing the time of the sounding, explaining the decrease of this parameter. The K, TT and LI instability indexes showed a close representation of the environment, predicting storms with heavy rainfall with 74% of correct identification, if taken into account the events on which all indexes showed the same indication of strong instability. Therefore, thermodynamic conditions of strong instability may lead to storms, but are not the only responsible factors for convective storms with extreme rainfall
Acesso aberto (Open Access)
Eventos extremos de precipitação em Belém-PA: uma revisão de notícias históricas de jornais
(2015-03) CAMPOS, Thamiris Luisa de Oliveira Bradão; MOTA, Maria Aurora Santos da; SANTOS, Sergio Rodrigo Quadros dos
This study examined the socioeconomic impacts of Daily Extreme Precipitation Events (hereafter "DEPEs") in Belem-Pará during the period 1987-2009. The DEPEs were characterized as "extreme" using the Decile technique. The objective of the study was to identify the consequences and the main neighborhoods affected by these events. The years influenced by occurrences of El Niño or La Niña had the lowest or the highest rates of DEPEs, respectively, and as well as the number of articles published in the city's newspapers. The monthly variation showed that the DEPEs and resulting newspaper articles were higher in the "wettest" (summer / austral autumn) period. The newspaper articles indicated that street flooding is the main consequence of DEPEs in the city of Belém-Pará, and that the most affected districts are Cremação, Jurunas and Batista Campos. These neighborhoods are near to one another and are all located in the Travessa Quintino Bocaiúva watershed, which has a low slope that delays the flow of water, favoring flooding. The city's lack of infrastructure is the main reason for the severe consequences of DEPEs.
Acesso aberto (Open Access)
Importância das condições termodinâmicas nos eventos extremos de precipitação na cidade de Belém e região metropolitana
(Universidade Federal do Pará, 2014-12) GILLE, Felipe do Souto de Sá; MOTA, Maria Aurora Santos da
The purpose of this research was to verify the importance of thermodynamic factors on the occurrence of extreme precipitation events in the city of Belém (PA) and its metropolitan area, during the period of August 2008 to December 2009. The study of the atmosphere thermodynamics was based on the theories of Convective Available Potential Energy (CAPE) and Convective Inhibition Energy (CINE). To classify the extreme precipitation events the decis method was used in order to associate them to the CAPE and CINE values. It was verified that the studied region has strong convective activity during all the year, and that not always high CAPE and low CINE determine precipitation. Those situations in fact determine profound convection, but to ensure precipitation, dynamic enforcement is required. For the occurrence of extreme precipitation events during the rainy season the ITCZ is the forcing dynamic and during the dry season the squall lines contribute to them. Then when the precipitation process is exclusively CAPE dependent, a high CAPE value is required in order to generate deep convection and, consequently, precipitation. Otherwise, for dynamic contribution precipitating process a significant value of CAPE is not needed.
Acesso aberto (Open Access)
Precipitação sazonal sobre a Amazônia oriental no período chuvoso: observações e simulações regionais com o RegCM3
(2009-06) SOUZA, Everaldo Barreiros de; LOPES, Marcio Nirlando Gomes; ROCHA, Edson José Paulino da; SOUZA, José Ricardo Santos de; CUNHA, Alan Cavalcanti da; SILVA, Renato Ramos da; FERREIRA, Douglas Batista da Silva; SANTOS, Daniel Meninéa; CARMO, Alexandre Melo Casseb do; SOUSA, José Raimundo Abreu de; GUIMARÃES, Paulo Lima; MOTA, Maria Aurora Santos da; MAKINO, Midori; SENNA, Renato Cruz; SOUSA, Adriano Marlisom Leão de; MOTA, Galdino Viana; KUHN, Paulo Afonso Fischer; SOUZA, Paulo Fernando de Souza; VITORINO, Maria Isabel
This paper presents a contribution on the climate modelling studies with emphasis on seasonal rainfall variability in eastern Amazonia, during the austral summer and autumn seasons (DJF and MAM). Based on RegCM3 regional climate simulations for a 26 years period (1982/83 to 2007/08) using high resolution domain scale (30 km) and two different convection schemes (Grell and MIT), it was investigated the model performance to simulate the regional pluviometric distribution in eastern Amazon, with reference to a new observational data base containing regional aspects extracted from a dense rain gauge station network. The quantitative analysis showed that RegCM3 presents systematic errors, especially those related to the dry bias in the Amapá and north/northeast of Pará using both schemes Grell and MIT, which indicate that the model does not reproduce ITCZ characteristics over equatorial Atlantic. The simulations using MIT also indicated wet bias in the southwest/south/southeast of Pará and north of Tocantins. Moreover, through composites technique, it was also investigated RegCM3 response to reproduce the anomalous spatial rainfall patterns in association with ENSO episodes and interhemispheric SSTa gradient phases across the intertropical Atlantic. The results showed that the model represented realistically well the spatial pattern related to the rainfall anomalies above (below) than normal in most of eastern Amazonia, during the known favourable scenarios, i.e., La Niña and south Atlantic SSTa gradient (unfavourable, i.e., El Niño and north Atlantic SSTa gradient).
Acesso aberto (Open Access)
Weather forecasting for Eastern Amazon with OLAM model
(2014-12) SILVA, Renato Ramos da; GANDU, Adilson Wagner; COHEN, Júlia Clarinda Paiva; KUHN, Paulo Afonso Fischer; MOTA, Maria Aurora Santos da
The OLAM model has as its characteristics the advantage to represent simultaneously the global and regional meteorological phenomena using the application of a grid refinement scheme. During the REMAM project the model was applied for a few case studies to evaluate its performance on numerical weather prediction for the eastern Amazon region. Case studies were performed for the twelve months of the year of 2009. The model results for those numerical experiments were compared with the observed data for the region of study. Precipitation data analysis showed that OLAM is able to represent the average mean accumulated precipitation and the seasonal features of the events occurrence, but can't predict the local total amount of precipitation. However, individual evaluation for a few cases had shown that OLAM was able to represent the dynamics and forecast a few days in advance the development of coastal meteorological systems such as the squall lines that are one of the most important precipitating systems of the Amazon.