O conhecimento de dados hidrometeorológicos de uma bacia é de fundamental importância para o planejamento e gestão da mesma, possibilitando a previsão hidrológica e climatológica, conhecendo-se assim as alterações que podem ocorrer na bacia. Para isso são necessárias longas séries de dados e, na maioria das vezes, estas séries possuem falhas que devem ser preenchidas para a aplicação das variáveis. Existem diversos métodos de correção de falhas, entretanto, a maioria depende de uma estação próxima com dados ou de variável para se correlacionar. O objetivo desta pesquisa foi buscar uma metodologia de imputação de dados hidrometeorológicos realizando uma análise das séries históricas, afim de estimar as variações na vazão da bacia hidrográfica do Rio dos Sinos. Para tanto, foram coletados dados de séries históricas de precipitação mensal, vazão máxima mensal e de temperatura máxima mensal entre os anos de 1985 a 2015, analisando-os estatisticamente para buscar a melhor forma de imputação de dados para, após, relacioná-los para avaliar alterações nos padrões históricos. Conseguiu-se aplicar uma metodologia simples que satisfez o preenchimento dos dados faltantes, não alterando as propriedades da série.

The objective of this chapter is to present the central concepts, parameters, and methods for the monitoring of climate changes, with a focus on air pollution, and the possible global and regional impacts of climate changes as well. There are plant species used as bioindicators that have a high sensitivity or ability to accumulate environmental pollutants. Another method that this chapter will present is the use of receiver models that employ both mathematical and statistical approaches to quantify the individual contribution of a given number of emission sources in the composition of a sample. The data presented in this chapter will provide reliable bases and methodologies for environmental control, supporting the adoption of more restrictive policies.

Climate change has become a worldwide theme discussed in the last decades, mainly about the various expected impacts. Some research claims that some of these impacts are already occurring, such as the change in the rainfall regime, causing more frequent droughts and floods, an increase in sea levels, among others. Based on this, monitoring water resources to analyze possible changes in hydrological behavior is fundamental for the proper planning and management of these resources. Therefore, the objective of this research was to evaluate the flow behavior in the Guaíba hydrographic region over a period of 33 years and disturb the series based on expected trends due to climate changes to assess how the flo ws can be affected. For this purpose, data on maximum m onthly flows for the period from 1985 to 2017 were obtained from ten fluviometric stations in the Guaíba hydrographic region, southern Brazil. These data were evaluated using descriptive statistics and permanence curves. Afterwards, the series were disturb ed and evaluated again. Through the observation of the historical behavior of the flow it was noticed that many stations indicate changes in the temporal variation, with a tendency to increase the number of great magnitude flows, but, on the other hand, it is verified the temporal increase of minimum flows. The projected trends for the region indicate an increase in the volume of precipitation and in the flow of the rivers, however they tend to be more concentrated in short periods of time.

Knowing the behavior of extreme hydrological phenomena is essential so that the impacts resulting from these natural events are minimized. Rio Grande do Sul has frequently been hit by extreme events such as droughts and floods, and these events are associated with several consequences, such as energy or water rationing, urban flooding and damage to hydraulic structures. In this context, the analysis of historical series extremes of hydrometeorological data through the Extreme Values Theory (EVT) is one of the ways to determine the variability due to climate change, enabling the modeling of extreme events. EVT makes it possible to know the frequency with which extreme events occur, allowing extrapolation beyond the historical series, generating occurrence probabilities of such an event. Therefore, the purpose of this work was to apply the Extreme Values Theory in hydrological the data historical series of flow and precipitation in the Guaíba hydrographic region and to carry out occurrence probabilities of intense events return, helping in the planning of the hydrographic watersheds that are in this region, as well as to verify whether the EVT has return periods similar to the climate projections of CMIP5 models. The results demonstrate that the values of flow and precipitation, in the historical series used, have already presented changes regarding the volume and frequency of extreme events occurrence and, in the future, for some stations, values can be expected both above and below the extremes already observed in the historical series.

The objective of this chapter is to present the central concepts, parameters, and methods for the monitoring of climate changes, with a focus on air pollution, and the possible global and regional impacts of climate changes as well. There are plant species used as bioindicators that have a high sensitivity or ability to accumulate environmental pollutants. Another method that this chapter will present is the use of receiver models that employ both mathematical and statistical approaches to quantify the individual contribution of a given number of emission sources in the composition of a sample. The data presented in this chapter will provide reliable bases and methodologies for environmental control, supporting the adoption of more restrictive policies.