Navegando por Autor "LOUREIRO, Glauber Epifanio"

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Acesso aberto (Open Access)
Avaliação quantitativa da dinâmica espaço-temporal da precipitação na região hidrográfica Tocantins-Araguaia
(Universidade Federal do Pará, 2012-01-31) LOUREIRO, Glauber Epifanio; FERNANDES, Lindemberg Lima; http://lattes.cnpq.br/4641468846318922
The analysis of the rainfall behavior in a watershed is fundamental for engineering and management of the hydric resources. The Tocantins-Araguaia Basin (TAB) for your recent occupation and economic potentialities, earns prominence in the national scenery. This work evaluates the spatial-temporal dynamics of the annual precipitation in this region quantitatively during a period of 30 years of data. The dynamics of rainfall can be analyzed by the calculation of the mean precipitation in a given area, by composing isohyets maps of annual precipitation. However, the confection of these maps require one interpolation method what better please represent the rainfall characteristics in places not shown for posterior please analyze quantitative of the behaviour of the rainfall. For much, went realized descriptive exploratory analyses sample and spatial how requisition of stationarity of the interpolation method geostatistics, fill and validation of the theoretical model what he embed to the variograma of annual rainfall. The confection of isohyets maps for the method of ordinary kriging (no drift) and Universal Kriging (drift) went afterwards realized the calculation of the precipitate volume in the hydrographic region for the method of the contours. The spatial dynamics of the precipitation was realized with base in the analysis of descriptive statistics, isohyets maps, map hypsometric, Meteorological Irregularity (MI) and Coefficient Variation. Temporal dynamics was analyzed by the distribution of the total annual of volumetric precipitation for every secondary basin of the TAB, Standarized Anomaly, in the variation interanual of precipitation and trend test and magnitude represented respectively by Mann Kendall Test and Sen's. Interrelated upshots with the meteorological anomalies of the Atlantic Ocean (Dipole) and Pacific (ENOS) indicate the behaviour of the enough precipitation heterogeneous and with big variability principally in the under subbasin Tocantins Alto (TOA) (14%.) Diminution of the pluviometric amplitude, in years of intense meteorological anomaly causing a precipitation increment to the south of the under basins TOA and Araguaia (ARA) and diminution of the precipitation to the north of the secondary subbasin Tocantins Baixo (TOB), in El Niño events. One cannot prove for Mann Kendall test precipitate in the TAB, has an trend significative statistically in the volume but the estimated Sen's gives clues of fall in the precipitation in the sub-basin TOA (-1,24 km³/year) and Araguaia (ARA) (-1,13 km³/year) and increase of the precipitation in the under basin TOB (0,53 Km³/year) and for the TAB (-1,5 km³/year). So spatial and temporal variability in the under basins is intimately reported to the events of meteorological anomaly, in which your action occurs of irregular way to the long of the area to study and lop influence the socioeconomic different activities in the TAB in accordance with your magnitude and area of occurrence.
Acesso aberto (Open Access)
Variação da precipitação por método de interpolação geoestatística
(2013-08) LOUREIRO, Glauber Epifanio; FERNANDES, Lindemberg Lima
This article analyses the variation of rainfall in the Tocantins-Araguaia hydrographic region in the last two decades, based upon the rain gauge stations of the ANA (Brazilian National Water Agency) HidroWeb database for the years 1983, 1993 and 2003. The information was systemized and treated with Hydrologic methods such as method of contour and interpolation for ordinary kriging. The treatment considered the consistency of the data, the density of the space distribution of the stations and the periods of study. The results demonstrated that the total volume of water precipitated annually did not change significantly in the 20 years analyzed. However, a significant variation occurred in its spatial distribution. By analyzing the isohyet it was shown that there is a displacement of the precipitation at Tocantins Baixo (TOB) of approximately 10% of the total precipitated volume. This displacement can be caused by global change, by anthropogenic activities or by regional natural phenomena. However, this paper does not explore possible causes of the displacement.