Se ha visto que estos últimos años las presiones sobre el territorio y los pueblos amazónicos se han vuelto cada vez más visibles debido a las transformaciones del suelo y las dinámicas territoriales sobre estas zonas antes consideradas remotas y en las que habitan pueblos primigenios. Frente a este contexto, se ha querido cuantificar los cambios en el territorio por actividades antrópicas cuantificando las transformaciones del suelo y los impactos sobre suelo no artificializado. En este sentido, se emplean imágenes satelitales nocturnas y diurnas que nos permiten cuantificar la evolución de los niveles de radiancia y los cambios en los NDVI. Estos dos indicadores nos permiten visualizar de manera clara las trasformaciones en los usos del suelo y los impactos de radiancia sobre el territorio. En este sentido, se ha corroborado que los impactos vinculados con la expansión de la frontera agrícola y urbana incrementan anualmente sus superficies a tasas que superan los 4,5% y que las actividades antrópicas se vinculan con las temperaturas más elevadas del territorio propiciando un cambio de las características propias de los ecosistemas selváticos.  Estos resultados evidencian la perdida de bosques tropicales, pero también y los impactos sobre los pueblos primigenios que habitan estos territorios. Palabras clave: Landsat, VIIRS, cambio de suelo, NDVI, Amazonía. AbstractIn the last years the pressures on the Amazon have increasingly become visible due to the transformations of the land and alteration of territorial dynamics in areas previously considered remote and only inhabited by indigenous nations. In this context, we evaluate anthropic-based changes by quantifying the transformations of land use and the impacts on non-artifcialized areas. Using night and day satellite images, we quantify the  evolution of radiance levels and changes in NDVI since 2012. We obtained a visualization of the transformations in land use and the radiance impacts on the territory. In this sense, this study found that the impacts related tothe expansion of the agricultural and urban frontier increase their infuence areas at rates that exceed 4.5%/year and that anthropic activities are linked to the highest temperatures in the territory, motivating a change of the characteristics of rainforest ecosystems. These results show the loss of tropical forests, but also suggests impacts on the indigenous inhabitants of these territories. Keywords: Landsat, VIIRS, soil change, NDVI, Amazon.

No abstract

<p>Hydropower operations are commonly prescribed as part of a grid-wide coordination process by an Independent System Operator (ISO). The scheduling problem is usually divided into two coupled problems: short- and medium-term scheduling. The medium term problem, usually within a planning horizon of a few years, takes into account uncertain inflows to every hydropower plant in the grid. This uncertainty is often represented by a scenario tree constructed from historical records. The result of this stochastic optimization problem is a set of Future Value Functions (FVF) of water in the reservoirs. These functions represent the carryover storage value, as avoided future thermal costs, for each week within the planning horizon. These FVFs are then used as a boundary condition for short-term scheduling within each week.</p><p>Chile has suffered a 10-year severe drought since 2010. Moreover, climate projections for Chile suggest an intensification of droughts in the future, in terms of both frequency and magnitude. From the water-energy nexus perspective, this phenomenon would rise energy costs and prices, and at the same time, push the electric coordinator to feed the system with less clean sources of electricity.</p><p>This work proposes and tests alternative ways to introduce plausible mega-droughts in Chile as part of the power scheduling process. We develop series representing plausible future conditions of drought and severe drought, preserving the time and spatial correlation structure of inflows. These scenarios are then used, along with historical information, to develop FVFs that take into account those severe drought scenarios. The method is tested in Chile’s main grid, represented by 624 power plants, 103 inflow points, 13 reservoirs, and 58 demand nodes.</p><p>The FVFs obtained from each alternative approach are then simulated under a wide range of futures. Results show that the introducing very severe droughts is not the best course of action, as the corresponding FVFs perform very poorly under moderately dry futures. In contrast, introducing scenarios with a moderate dry bias performs better over a wide range of future conditions, except for extremely severe droughts.   </p>