Faculdade de Meteorologia - FAMET/IG

URI Permanente desta comunidadehttps://repositorio.ufpa.br/handle/2011/2798

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Agora exibindo 1 - 7 de 7

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)
Climatologia da estrutura vertical da atmosfera em novembro para Belém-PA
(2010-06) ANANIAS, Daniela dos Santos; SOUZA, Everaldo Barreiros de; SOUZA, Paulo Fernando de Souza; SOUSA, Adriano Marlisom Leão de; VITORINO, Maria Isabel; TEIXEIRA, Gleyciano Mendes; FERREIRA, Douglas Batista da Silva
The present work reports a diagnostic study on the vertical structure of air temperature, dew point temperature and relative humidity over the region of Belém-PA (eastern Amazon), based on monthly dataset for a period of 26 years (1982 to 2007). The focus is on the transition period from dry to wet season in the eastern Amazon, i.e., the month of November. Two contrasting composites in relation to the rainfall regime were considered: the wet and the dry year's composites, which were established objectively by the percentiles method. The results showed that the main difference observed in the temperature and humidity profiles, comparing dry and wet years, occurs in the atmospheric layer between the middle and upper levels of the troposphere (between the patterns level from 700 hPa to 400 hPa). In this layer, the difference between air temperatures and dew point is significantly higher and the contrast of moisture associated with convection also shows the highest values. In general, the compositions showed that the temperature profiles anomalously warmer (cold) and the moisture profiles anomalously wetter (dry) are associate to the years of rainfall above (below) of normal in the region of Belém-PA.
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)
Lightning and precipitation produced by severe weather systems over Belém, Brazil
(2014-12) RIBEIRO, Wanda Maria do Nascimento; SOUZA, José Ricardo Santos de; LOPES, Marcio Nirlando Gomes; CÂMARA, Renata Kelen Cardoso; ROCHA, Edson José Paulino da; ALMEIDA, Arthur da Costa
CG Lightning flashes events monitored by a LDN of the Amazon Protection System, which included 12 LPATS IV VAISALA sensors distributed over eastern Amazonia, were analyzed during four severe rainstorm occurrences in Belem-PA-Brazil, in the 2006-2007 period. These selected case studies referred to rainfall events, which produced more than 25 mm/hour, or more than 40 mm/ 2 hours of precipitation rate totals, registered by a tipping bucket automatic high-resolution rain gauge, located at 1º 47' 53" S and 48º 30' 16" W. Centered at this location, a 30 ,10 and 5 km radius circles were drawn by means of a geographic information system, and the data from lightning occurrences within this larger area, were set apart for analysis. During these severe storms the CG lightning events, occurred almost randomly over the surrounding defined circle, previously covered by mesoscale convective systems, for all cases studied. This work also showed that the interaction between large-scale and mesoscale weather conditions have a major influence on the intensity of the storms studied cases. In addition to the enhancement of the lightning and precipitation rates, the electric activity within the larger circles can precede the rainfall at central point of the areas.
Acesso aberto (Open Access)
Variabilidade da precipitação em tempo e espaço associada à Zona de Convergência Intertropical
(2012-12) MOURA, Mauricio do Nascimento; VITORINO, Maria Isabel
This study aims to present an atmospheric analysis of spatial and temporal variability of the Intertropical Convergence Zone (ITCZ) in Belem, Jakarta and Nairobi, which are located on the continents of South America, Asia and Africa, respectively. For this, daily precipitation and observed long wave radiation data for the period 1999 to 2008 were used, and mathematical and statistical techniques, such as the arithmetic mean and the Morlet wavelet transform were applied. In general, the results indicate that spatially, the month rainfall varies considerably, since that the three studied cities are located far apart in different continents in the tropical zone. This occurs mainly during the months from January to May, period of greatest activity of the ITCZ in the southern hemisphere. The atmospheric variations observed from the phase wavelet scalograms indicate that the interdecadal scales, annual, interannual and intraseasonal scales are rainfall modulators. Such scales can be represented by the ocean-atmosphere phenomenon mechanisms of El Niño Southern Oscillation and intraseasonal oscillation of Madden and Julian. The contribution of these phenomena to the rainfall distribution over these regions is evident during the study period, and Nairobi, in spite of being located at latitude similar to that of Belem, shows low evidence of the annual cycle and high at interdecadal scale. In the case of Belem and Jakarta oscillations at multiscale rainfall concentrated in the mechanisms scales that modulate the rain associated with the annual cycle and intraseasonal cycle during the period.
Acesso aberto (Open Access)
Variabilidade espacial do conforto térmico e a segregação social do espaço urbano na cidade de Belém, PA
(2013-12) SILVA JUNIOR, João de Athaydes; COSTA, Antonio Carlos Lôla da; PEZZUTI, Juarez Carlos Brito; COSTA, Rafael Ferreira da
This work contributes to the study of urban climate in Belém, PA, during the lesser rainy season, along with an analysis of social segregation issues on urban space. A campaign for collecting meteorological data during the lesser rainy season on the region was made. The data were used to calculate the thermal comfort index inside the neighborhoods and compare them with the characteristic social types in each neighborhood. The results indicated that the West and Central areas of the city were less comfortable, because they are more urbanized and have less vegetation than other areas, while the East and West areas were more comfortable, with more vegetated areas and predominance of low buildings. The analysis indicated that there is not a well-defined pattern between the neighborhoods social types and theirs thermal comfort conditions, because the surface characteristics are more significant to the local microclimate changes.
Acesso aberto (Open Access)
Vulnerabilidade e mudanças climáticas: análise socioambiental em uma mesorregião da Amazônia
(Universidade Federal do Pará, 2017-10) SANTOS, Marcos Ronielly da Silva; VITORINO, Maria Isabel; PIMENTEL, Marcia Aparecida da Silva
The study of socio-environmental vulnerability associated with climate change is one of the topics most discussed by the international scientific community. The effects of climate change on society stem from different causes and effects; their analysis must take into account the cultural, economic and social context of a population. Thus, studies involving risks associated with extreme weather events must be done in an integrated and interdisciplinary way. In this context, the present research aims to contribute to vulnerability analysis in the metropolitan mesoregion of Belém, with a view to reducing the effects caused by climate and social changes. In order to do so, the General Vulnerability Index (GVI) was applied, based on socioeconomic, epidemiological and climatic indicators from 2000 to 2010. The results found that the municipality of Belém had the highest value of GVI (0. 61), indicating a high vulnerability, presenting the highest indexes of climatic (1.00) and epidemiological (0.76) vulnerability. On the other hand, the municipality of Bujaru has a low vulnerability, with a GVI value of 0.14, explained by the minimum value of the index of climate vulnerability (0.00) and low indices of epidemiological (0.03) and socioeconomic vulnerability (0.38). We expect that this study may support the management of public policies for the municipalities and encourage studies of socio-environmental vulnerability in the Amazon region, with an interdisciplinary approach.

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