José Ivaldo Barbosa de Brito

Análise dos índices de extremos para o semi-árido do Brasil e suas relações com TSM e IVDN

The objective this paper is verify the tendencies of indexes of detection of climate changes, dependent of the daily precipitation, in the states of RN and PB and to analyze your relationships with NDVI and anomalies of SST in the areas of Nino 1+2, Nino 3, North Tropical Atlantic Ocean (TNA) and South Tropical Atlantic Ocean (TSA). It was used data of precipitation of 44 locations, in the period from 1935 to 2000, representing all the regions of two States; of IVDN, obtained of NOAA/AVHRR, in the period from 1980 to 2000 and of anomalies of SST, given in by NOAA, from 1950 to 2000. A tendency of increase of the humidity conditions was observed on the two states. The index dry consecutive days it presented correlation significant statistically with the anomalies of SST of the areas TNA and TSA. While, the indexes very humid days and maximum amount of rain in five days they showed significant correlations with the areas of Nino 1+2 and 3 and with TNA. In general, it was observed that NDVI of the Savanna is more dependent of the precipitation ends than the one of the Atlantic forest. In agreement with the obtained results it was ended that the climatic changes detected by the indexes they are resulting as much of the factors of great scale as of local scale. Another obtained result was influence of ENSO on the extreme indexes of rain and consequently on climate and the dynamics of the vegetation of the Semi-arid.

Trends of precipitation indices in Ceará State.

The principal objective of this work is to provide new information on the trends in the total precipitation and extreme events of precipitation in the State of Ceara, making an analysis of different indices of detection of climatic changes, based on data of daily precipitation. Precipitation data of 18 stations were used, in the period from 1935 to 2006, representing all the microregions of the State; the software used in the processing and quality control of the data was RClimdex 1.9.0. The results show local changes in the precipitation and a visible increase in the humidity conditions in Ceara.

Relationship between the surface temperature on the tropical oceans and the duration of dry spells in the Paraíba State

This paper has the objective of verifying the possible influences of the anomalies of sea surface temperature (SST) in the Equatorial Pacific and in the Tropical Atlantic on the duration of the largest dry spell of the rainy season of the micro-regions of the Paraiba State. Daily precipitation data of the rain gauge stations distributed in the all sectors of Paraiba, for the period from January 1, 1963 to December 31, 1999, the monthly anomalies of SST in the area of the ninos: Nino 1+2, Nino 3, Nino 3.4 and Nino 4, and monthly indices of North and South Tropical Atlantic, for the period from October, 1962 to December, 1999, obtained from the Diagnostic Center of Climate of the NOAA were used in this study. Correlations and graphs obtained between the anomalies of SST and the dry spell are analyzed. The results obtained showed that the dry spells of the micro-regions of the Coast and Swamp areas are more influenced by the conditions of anomalies of SST on Tropical Atlantic, while the dry spells of the micro-regions of Cariri/Curimatau and Interior, in the central part and west of the State are influenced by the SST of Equatorial Pacific.

Dry spells and agricultural production in the State of Paraíba, Brazil

It was sought, in this study, to verify the relationship between the duration, in days, of the largest dry spell and the productions of sugarcane, rice, pineapple, cotton, sisal, corn and bean, for the mesoregions of the State of Paraiba. The meteorological data used consisted of daily series of precipitation of pluviometric stations located in the state, over the period of January 1, 1963 to December 31, 1999. On the other hand, data of annual agricultural production of sugar-cane were used in million of tons, rice, cotton, sisal, corn and bean, in thousands of tons and pineapple, in millions of fruits for the Paraiba state, in the period from 1975 to 1994. It was verified that the productions of sugarcane, rice and pineapple, in the mesoregion [1] are independent of the duration of the dry spell, while the production of corn and bean, in the mesoregion [2+ 3] is highly dependent upon the duration of the dry spell events in those mesoregions. It is concluded, therefore, that the consideration of the dry spell occurrence for the mesoregion [2+ 3] is important in the agricultural planning, perhaps, even more significant than the forecast of the total precipitation, because in a specific year it may rain above the average due to concentration of rains over a few days.

Indices of trends of climatic changes for the states of the Bahia and Sergipe by means of daily precipitacion indices and its relation with SST'S of the Pacific and Atlantic

The objective of this study was to investigate statistically the precipitation variability in annual scale from the states of the Bahia and Sergipe using daily precipitation data. From that, indexes of detection of climate changes were calculated to evaluate the relationship of the most significant indexes with the sea surface temperature (SST) anomalies of the Pacific and Atlantic oceans. The daily precipitation data used were for a period of 45 years of 75 meteorological stations supplied by the old net of the SUDENE available in the DSA and data of the of the SST anomalies obtained from NOAA. Influence of SST of the Pacific and Atlantic oceans on the precipitation of the studied area is evidenced. A decrease of CWD was verified; increase was observed in the number days with rain; therefore, the amount of annual total precipitation increased. Several stations presented positive or negative tendencies in all examined indexes, consequently, they are also related to regional aspects. Therefore, it is not possible to affirm that the climate alterations noted in the study area are due to the global climate changes.

MODELO DE VEGETAÇÃO POTENCIAL PARA A REGIÃO NORDESTE DECORRENTE DA PRECIPITAÇÃO PLUVIAL ( 1 )

POTENTIAL VEGETATION MODEL FOR THE NORTHEAST REGION OF BRAZIL AS A FUNCTION OF PRECIPITATION The present work applies the model of Rey to calculate the potential vegetation of the Northeast of Brazil and, thus, to verify if it properly identifies the biomes of that region. The method used to calculate the rate of Evapotranspir ation (ET) is based on the equation of Penman-Montei th. The model also includes fixed parameters and the variables vegetation height and leaf area index (LAI). In general, the model provided a good representation of the biomes of the Northeast of Brazil, mainly the Caatinga, the Cerrado, and the Atlantic Forest.

Eventos extremos de precipitação nas mesorregiões da Paraíba e suas relações com a TSM dos oceanos tropicais

The aim of this study was to identify trends in extreme precipitation indices on the Paraiba State, and to correlate them with the Sea Surface Temperature (SST) anomalies in the Atlantic and Pacific Oceans. The daily precipitation data for the period 1935-2004, were from 23 rain gauges belonging to Instituto Nacional de Meteorologia (INMET). To calculate the extreme rainfall indexes the RClimdex software was used. Then, the statistical least squares method and the non-parametric Mann-Kendall test were applied to identify trends and their statistical significance. The correlation between the extreme precipitation indices and the SST were then calculated. It was found a higher number of sites with positive trends in the period 1935 to 1969, and the highest correlations were with the Atlantic. The Sertao and Agreste Mesoregions of Paraiba state were well related to SST anomalies in the Atlantic, Pacific and Atlantic Multidecadal Oscillation (AMO), Borborema with the AMO and the Atlantic and the Litoral with Atlantic.

Tendências de Índices de Extremos Climáticos para o Estado do Amazonas e suas Relações com a TSM dos Oceanos Tropicais

This study aimed to analyze the trends of eleven indices of climate extremes depend on daily precipitation for the state of Amazonas, dividing it into four mesoregions, as well as, to evaluate its relationship with SST anomalies in the Pacific (ENSO) and Atlantic (Atlantic Dipole) Oceans. The daily rainfall data for the period 1970-2010 were derived from INMET. Data of monthly anomalies of SST in the Tropical Oceans were obtained from CPC / NOAA. The results show that in the state of Amazonas is not possible to affirm categorically that there was an increase or decrease of extreme precipitation events in recent decades. Furthermore, it was found that the SST in the equatorial Pacific and Atlantic Tropical Oceans showed statistically significant correlations with indices of extreme precipitation. Thus, it is possible states that SST anomaly in these areas has an influence on precipitation rates in the state of Amazonas.

Classificação de Eventos Extremos de Precipitação em Múltiplas Escalas de Tempo em Belém-PA: Utilizando o Índice de Precipitação Normalizada (Classification of Extreme Precipitation Events in Multiple Time Scales in Belém, PA: Using the Standardized ...)

O Indice de Precipitacao Normalizada (SPI) e utilizado para quantificar o deficit e/ou excesso de precipitacao nas multiplas escalas de tempo. Ele tem se mostrado bastante util no monitoramento da precipitacao, principalmente pela sua flexibilidade, simplicidade de calculo e interpretacao. Desta forma este estudo tem como objetivo quantificar os eventos extremos secos e chuvosos na cidade de Belem-PA nas escalas de tempo de 3, 6 e 12 meses por meio do SPI. Para isto, utilizaram-se dados mensais de precipitacao provenientes da estacao meteorologicas de superficie do INMET no periodo de 1980-2011. Os resultados mostraram que a escala de tempo do SPI e inversamente proporcional a frequencia dos eventos de chuva e seca. Os SPIs 3,6 e 12 mostraram mais eventos secos do que chuvosos para a cidade e a maioria dos eventos de chuva e seca estavam associados, principalmente, ao fenomeno ENOS. ABSTRACT The Standardized Precipitation Index (SPI) is used to quantify the deficit/ excess rainfall at multiple time scales. It has been very useful in monitoring of precipitation, mainly because of its flexibility, ease of calculation and interpretation. Thus this study aims to quantify the extreme wet and dry events in the city of Belem-PA in time scales of 3, 6 and 12 months by SPI. For this, we used monthly precipitation data from meteorological station at the INMET in the period 1980-2011. The results show that the timescale of the SPI is inversely proportional to the frequency of rain and dry events. The SPIs 3.6 and 12 showed driest events that rainy events to the city and most of the rainfall and drought events were associated, mainly, with the ENSO phenomenon. Key Words : Belem; SPI; Extreme Event.

Trends in precipitation extremes over the Northern part of Brazil from ERA40 dataset (Tendências nos Extremos de Precipitação sobre a Parte Norte do Brasil através dos Dados do ERA40)

A B S T R A C T Trends in extreme climate indices were obtained with ERA40 gridded precipitation data over northern Brazil region that includes most of the Amazon Basin and interior of Northeast Brazil. The indices representing one-day highest precipitation in a month, number of rainy days, monthly maximum 5-day consecutive precipitation and number of heavy precipitation days showed increasing trends over most of the grid points of the study region. Although negative trends in wet days were obtained at some grid points, they are not statistically significant. The negative trends are mostly confined to Mato Grosso and southern Para states, where the deforestation in the period of study was intense. Consistently, the index representing the number of dry days showed a negative trend at the points where the number of wet days, very wet days and annual precipitation amounts showed positive trends.