Sâmia Regina Garcia

Revised method to detect the onset and demise dates of the rainy season in the South American Monsoon areas

This paper proposes the detection of dates for the onset and demise of the rainy season (ONR and DER, respectively) for some areas within the South American monsoon system (SAMS) region using procedures based on indices which could be easily calculated and subjected to very simple criterion. Previously, the time series of the averaged antisymmetric outgoing longwave radiation ([AOLR]) in each region of interest was used by some authors to detect ONR and DER. This method is referred to as OLD. First, it was proposed in this paper to smooth this time series with the five-pentad running mean ([RM_AOLR]). This modified method is called NEW. Then, an additional modification was adopted by smoothing the [AOLR] with the three-pentad running mean but with the [AOLR] in the most recent pentad being replaced by its climatological value ([RM_AOLRCLI]). This method is called NEW_CLI. For these methods, the criterion was that the first pentad with negative (positive) [AOLR] (or [RM_AOLR] or [RM_AOLRCLI]) is the ONR (DER) date in the region of interest. All these methods were applied for the Central Amazon (CAM) and Western-Central Brazil (WCB) regions during the rainy seasons in the 2001–2013 period. The efficiency of these methods was analyzed using the precipitation estimated from the Tropical Rainfall Measuring Mission (TRMM) Multisatellite Precipitation Analysis. The spatial average of the TRMM ([TRMM]) time series with threshold values, which depends on the area and season, was used to determine the ONR and DER dates. In this case, the single method based on the threshold value is called RAIN, and the method which considers the persistence of dry or wet condition is referred to as NEW_RAIN. Comparisons between the methods were performed by calculating the root mean square error (RMSE) when ONR and DER dates obtained from a given method were considered as the true dates. The advantages and disadvantages of the methods were discussed here. It was previously noted that the [AOLR] time series during the transition from dry (wet) to wet (dry) season showed several signs of oscillation. This was a weakness when detecting the ONR and DER dates; however, using the NEW and NEW_CLI methods eliminated this problem. The NEW_CLI method has more advantages than the other methods and will be useful for monitoring the ONR and DER dates of the SAMS regions.

Relação dos sistemas de monção com as variabilidades tropical interanual e multi-decenal

Tropical circulation variability, with emphasis on the monsoon systems is examined using several variables for the 1948-1999 period. The monsoon component in the 200 hPa velocity potential (transient-χ), the deviation from the annual mean of the zonal deviation field, is the key parameter used here to obtain the monsoon modes. The Empirical Orthogonal Function (EOF) analysis of the transient-χ yields two separate modes. The first mode describes the multi-decadal variability of the monsoon systems in South America and in the western Pacific. This mode, called the multi-decadal monsoon (MDM) mode, occurs throughout the year and contains the multi-decadal variability linked to the PDO dynamics. The second mode describes the opposite interannual variations of the Asian, African and Indian Ocean region and western United States, Mexico and eastern Pacific Ocean. This mode, called here the interannual mode (IAM) bears some similarities with the tropical interannual El Nino-Southern Oscillation mode. Some aspects of these modes, including their circulation and thermodynamic characteristics are discussed here. Finally, indices based on the loading patterns of these modes are constructed. The potential of these indices for monitoring tasks are analyzed. This is a new aspect not proposed in previous work.

Início e Fim da Estação Chuvosa no Estado de Minas Gerais: Comparação de Duas Metodologias Diferentes

The Onset and Demise of the rainy season (ONR and DER, respectively) are found in Minas Gerais (MG) for the 1998-2012 period with two methodologies: one using daily rainfall data and another that using daily data of antisymmetric equatorially outgoing longwave radiation (AOLR). The ONR (DER) is indicated by a sign change from positive-negative (negative-positive) of the AOLR spatial averages, as in Garcia and Kayano (2009; 2013), whereas for the Liebmann et al. (2007) method that date is determined by the minimum (maximum) of the anomalous accumulation of daily precipitation. For comparison, the daily precipitation series in the region are also analyzed. The ONR dates found by both methods are closer to each other compared to the DER, which has greater variability in both methods. Both methods detect the ONR and DER dates in MG with quality and the main differences between them are discussed in the text. It is worth noting that the Garcia and Kayano (2009; 2013) method is relatively more advantageous when compared to the method of Liebmann et al. (2007), because it depends solely on the OLR data, which are available on near real-time basis, different of the indices based on precipitation; and also to be independent of the analyzed period, which is characteristic of the Liebmann et al. (2007) method.

QUALITY EVALUATION OS ENVIRONMENTAL LICENSING PROCESSES OF MININ ENTERPRISES IN MINAS GERAIS

The environmental licensing has generated uncertainties about its effectiveness; making it necessary to encourage mechanisms to improve the political-institutional setting. Thus, this study aimed at evaluating the legal and technical concordances of the environmental licensing processes of mining enterprises in the south of the state of Minas Gerais. Using checklists, thirteen licensing processes were analyzed, where the preand post-approval stages were assessed. It was observed that the environmental studies didn’t correspond to the terms of reference and the expected quality, as well as the noncompliance of the proponents regarding the approval of the environmental management reports. Therefore, it was concluded that there is a lack of technical performance of the analysts of the competent environmental agency and, therefore, it is necessary to improve the technical evaluation system of environmental studies as a tool to improve EIA processes.

Moisture and heat budgets of the south American monsoon system: climatological aspects

The climatology of the moisture and heat budget equation terms for subareas within the South American Monsoon System (SAMS) region is investigated for the 1958–2014 period considering the distinct phases of the Pacific Decadal Oscillation (PDO). These budget equations are applied to the data from the National Centers for Environmental Prediction (NCEP) Reanalysis project. Sources or sinks of moisture and heat are equation residues, referred to as residue and diabatic terms, respectively. Analyses are done for the Central Amazon Basin (CAM) and Western-Central Brazil (WCB) for three distinct periods, 1958–1976, 1977–1995, and 1996–2014, that correspond to the cold, warm, and undefined PDO phases. The differences among the PDO phases for each term are discussed. The CAM region acts dominantly as a moisture sink and heat source in all months during the three phases. On the other hand, in the WCB region, the monsoon characteristics are better defined, with a moisture sink (source) and a heat source (sink) during the wet (dry) season. The main result of the present analysis is the persistence of SAMS intensification signs in both CAM and WCB areas up to the last analyzed period (1996–2014), which is consistent with intense flooding in the Amazon Basin in 2008/2009, 2012, and 2014.

Análise dos Processos de Licenciamento e Monitoramento de Minerações em Minas Gerais (Extraction of ornamental rocks licensing and monitoring processes analysis in Minas Gerais)

O licenciamento ambiental tem se instaurado em diversos paises, em razao das severas alteracoes no meio ambiente. No entanto, ha presenca constante de conflitos socioambientais nas tomadas de decisoes e tramitacoes no regimento do licenciamento. Desta perspectiva, o objetivo deste trabalho foi avaliar o comportamento dos empreendimentos minerarios do Sul de Minas Gerais em relacao as fases de licenciamento e monitoramento ambiental. Utilizou-se para tal, listas de verificacao compostas por: variaveis tecnicas dos estudos ambientais e variaveis tecnicas administrativas. Foram selecionados, treze processos de licenciamento de empreendimentos de mineracao, onde se avaliaram ambas as fases. Observou-se que, na fase de licenciamento, ao contrario dos empreendimentos que homologaram estudos de impacto ambiental, os que homologaram relatorios de controle ambiental, nao atenderam as premissas exigidas tecnicamente, inviabilizando assim, a capacidade tecnica do estudo ambiental. No que se refere a fase de monitoramento, os planos de controle ambiental e de recuperacao de area degradada, assim como na fase anterior, nao cumpriram satisfatoriamente as exigencias tecnicas. No entanto, destacou-se o baixo percentual de homologacao das medidas de controle ambiental, tonificando assim, a incapacidade de eficiencia do monitoramento. Portanto, e possivel concluir que, a negligencia dos parte dos empreendedores e de corresponsabilidade do sistema operacional competente a executar o licenciamento ambiental. E por assim dizer, e necessario reestruturar as politicas ambientais em Minas Gerais, a fim de, atender eficientemente as diretrizes da avaliacao de impacto ambiental.