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Annually, anthropogenic fires devastate large areas of forest and grasslands over the world, releasing a large amount of greenhouse gases and aerosols into the atmosphere. This issue affects the environment, altering the atmospheric and surface radiation balance, besides the biogeochemical and hydrologic cycles. The main objective of this work is to use the fire radiative energy (FRE) release rate to estimate carbon monoxide (CO), particulate matter of less than 2.5 microns in diameter (PM2.5μm) and the amount of biomass consumed by fires in the South America 2002 season. For this, combustion experiments near the Laboratory of Radiometry (LARAD) of Remote Sensing Division at the National Institute for Space Research (DSR/INPE) were performed to obtain the coefficient that relates the consumption of biomass with the Fire Radiative Energy (FRE) released rate. The emission inventory estimated by Moderate Resolution Imaging Spectroradiometer (MODIS) and Wildfire Automated Biomass Burning Algorithm (WFABBA) from Geostationary Operational Environmental Satellites (GOES) Fire Radiative Power (FRP) measurements to the South America 2002 dry season were included in Coupled Chemistry-Aerosol-Tracer Transport model coupled to the Brazilian developments on the regional Atmospheric Modeling System (CCATT-BRAMS). The model results were evaluated with South America 2002 surface data collected in the Large Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) Smoke, Aerosols, Clouds, rainfall and Climate (SMOCC) and Radiation, Cloud and Climate Interactions (RaCCI) experiment. Evaluation of model and ground data revealed a good conformity with SMOCC/RaCCI data in the general pattern of temporal evolution. The results showed high correlations, with values between 0.80 and 0.95 (significant at 0.01 level by student t test), in PM2.5μm and CO emissions simulated in CCATT-BRAMS model. For the period analyzed, biomass consumed by fires can exceed 5 Tg (teragrams) in South America, with a daily average of 2.2 Tg (0.8 Tg estimated by MODIS and 1.32 Tg estimated by GOES). As a result, the coefficient derived from the relationship between biomass consumption and FRE released estimated the biomass burned from July to November 2002 in the South America dry season in approximately 0.28 ± 0.07 Pg (pentagrams).

As well documented by the scientific literature and strongly stated by the Intergovernmental Panel on Climate Change (IPCC), changes in the atmosphere composition, due to increasing emissions of greenhouse gases (GHG), may result in drastic environmental consequences, both in a regional and in a global scale. A substantial portion of the annual GHG emissions comes from the production of energy, which, in general, is produced from non-renewable sources. Coal dominates the electricity generation globally, accounting for 42 percent of total generation in 2007. As a renewable alternative, hydropower accounts to 18% of the global electricity production. However, concerns about the relation between carbon emission per unit of energy produced were raised in the scientific community in recent years. This concern is particularly important in tropical and sub-tropical regions, where temperature and the amount of flooded organic matter can be a fueled combination on the emission of greenhouse gases, in special methane. From 2003 through 2008 an extensive research program was carried out in 8 large reservoirs located in a broad geographical distribution in Brazil. The major goals on the project were: to determine the emissions of GHG to the atmosphere; to identify the pathways of the carbon cycle in the reservoirs; to evaluate the influence of morphometric, biogeochemical, biological and operational variables on the GHG emissions; and to develop a spatial and temporal model of the greenhouse gas emissions in reservoirs. In this chapter our aim is to report results and integrative outcomes from this study, as well as policy recommendation on managing hydropower systems in tropical regions.

The Amazon River system is the single, largest source of freshwater on Earth and its flow regime is subject to interannual and long-term climate variability, which translate into large variations in downstream discharge (Richey et al., 1989; Marengo and Nobre, 2001; Marengo 2004, 2005, 2006, 2007; Milly et al., 2005, Marengo et al., 2008a, b; Cox et al., 2008; Zeng et al., 2008). To predict future climate (rainfall) change and consequent river variability an understanding of the physical mechanisms related to regional and large-scale atmosphericoceanicbiospheric forcings is required. The temporal and spatial nature and impact of any variability in the hydrometeorology of the Amazon Basin must be considered in this context.

This work presents a contribution towards generalising the representation of geospatial entities and their relations for simulating complex spatial systems using the agentbased approach. We analyse the literature, and argue that each of the four types of relation is necessary. These relations can be grouped in two classes, placements and neighbourhoods, with likenesses and differences between them. Given that, we define requirements for representing geospatial entities and their relations, and study seven agent-based modelling toolkits (NetLogo, OBEUS, Repast, Swarm, Cormas, GRSP, and TerraME), analysing their capabilities to address the proposed requirements. Finally, we present our current work and future directions on developing TerraME.

The tropical Andes1 harbor extraordinary biological and cultural diversity, contained in a mosaic of ecosystems (Josse et al. 2009). The regions complex topography, coupled with elevational and latitudinal gradients, results in varied physical conditions that create unique habitats and barriers for species movement. Temporal variability of climatic conditions, such as temperature, wind, and precipitation, also occurs across the tropical Andes over inter-annual and decadal time scales, as driven by the interplay between the tropical Pacific and Atlantic Oceans, and Amazonian influences (Marengo et al. 2004). Both humans and biota have adapted to the heterogeneity of the tropical Andean landscape and fluctuations in climatic conditions. An estimated 45,000 plant and 3400 vertebrate species (excluding fishes) have been documented from tropical Andean ecosystems, representing approximately 15% and 12% of species known globally, respectively. Nearly half of these species are endemic (Myers et al. 2000). The wellbeing of human populations has been linked to the functioning of tropical Andean ecosystems over a history that extends more than 10,000 years. Today, millions of people depend on these ecosystems as a source of fresh water, food, cultural importance, and many other ecosystem goods and services (Josse et al. 2009). Recently, the range of natural climatic variability in the tropical Andes has started to exceed historically documented thresholds. Of particular concern is the general warming trend and its implications for the integrity of ecosystems and the human populations that depend on them. In this chapter, we explore current knowledge of the effects of climate change on tropical Andean ecosystems and ecosystem services. At present, other than unambiguous indications of a pronounced warming trend, the overall picture of the climatic future of the tropical Andes remains uncertain, making predictions about the fate of ecosystems difficult. Some studies on recent climate variability have been published, but much information remains observational or anecdotal. The information presented here was gathered from discussions among climatologists, ecologists, anthropologists, and natural resource managers with expertise in the tropical Andes during a weeklong workshop designed to facilitate transfer of knowledge on climate change and tropical Andean biodiversity, together with a review of literature and other available information.