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Land-use and land-cover change (LULCC) models are important tools for environmental policy planning. LULCC models are frequently constrained to the generation of projections at a specific resolution. However, subsequent studies or models may require finer resolutions. In this work, a downscaling method for LULCC models is proposed that uses a mathematical programming approach to disaggregate the multiple layers of the land-use change projections while respecting a series of constraints. The method is calibrated and validated with MapBiomas data for the years 2000 and 2018 converted for the GLOBIOM-Brazil model, successfully predicting land-use at a finer resolution. Also, as proof of concept, the calibrated model is also applied for GLOBIOM-Brazil projections for 2050. This paper advances the state-of-the-art by proposing and testing a downscaling method using a mathematical programming approach with spatial effects, that operates on multi-layered land-use projections with a range of constraints while allowing flexibility on the number and type of the specific layers and constraints. [ABSTRACT FROM AUTHOR]

Most of the world's nations (around 130) have committed to reaching net‐zero carbon dioxide or greenhouse gas (GHG) emissions by 2050, yet robust policies rarely underpin these ambitions. To investigate whether existing and expected national policies will allow Brazil to meet its net‐zero GHG emissions pledge by 2050, we applied a detailed regional integrated assessment modelling approach. This included quantifying the role of nature‐based solutions, such as the protection and restoration of ecosystems, and engineered solutions, such as bioenergy with carbon capture and storage. Our results highlight ecosystem protection as the most critical cost‐effective climate mitigation measure for Brazil, whereas relying heavily on costly and not‐mature‐yet engineered solutions will jeopardise Brazil's chances of achieving its net‐zero pledge by mid‐century. We show that the full implementation of Brazil's Forest Code (FC), a key policy for emission reduction in Brazil, would be enough for the country to achieve its short‐term climate targets up to 2030. However, it would reduce the gap to net‐zero GHG emissions by 38% by 2050. The FC, combined with zero legal deforestation and additional large‐scale ecosystem restoration, would reduce this gap by 62% by mid‐century, keeping Brazil on a clear path towards net‐zero GHG emissions by around 2040. While some level of deployment of negative emissions technologies will be needed for Brazil to achieve and sustain its net‐zero pledge, we show that the more mitigation measures from the land‐use sector, the less costly engineered solutions from the energy sector will be required. Our analysis underlines the urgent need for Brazil to go beyond existing policies to help fight climate emergency, to align its short‐ and long‐term climate targets, and to build climate resilience while curbing biodiversity loss. [ABSTRACT FROM AUTHOR]

In this paper, we make a bifurcation analysis of a mathematical model for an electric circuit formed by the four fundamental electronic elements: one memristor, one capacitor, one inductor and one resistor. The considered model is given by a discontinuous piecewise linear system of ordinary differential equations, defined on three zones in ℝ3, determined by |z| < 1 (called the central zone) and |z| > 1 (the external zones). We show that the z-axis is filled by equilibrium points of the system, and analyze the linear stability of the equilibria in each zone. Due to the existence of this line of equilibria, the phase space ℝ3 is foliated by invariant planes transversal to the z-axis and parallel to each other, in each zone. In this way, each solution is contained in a three-piece invariant set formed by part of a plane contained in the central zone, which is extended by two half planes in the external zones. We also show that the system may present nonlinear oscillations, given by the existence of infinitely many periodic orbits, each one belonging to one such invariant set and passing by two of the three zones or passing by the three zones. These orbits arise due to homoclinic and heteroclinic bifurcations, obtained varying one parameter in the studied model, and may also exist for some fixed sets of parameter values. This intricate phase space may bring some light to the understanding of these memristor properties. The analytical and numerical results obtained extend the analysis presented in [Itoh & Chua, 2009; Messias et al., 2010]. [ABSTRACT FROM AUTHOR]

Brazilian agricultural production provides a significant fraction of the food consumed globally, with the country among the top exporters of soybeans, sugar, and beef. However, current advances in Brazilian agriculture can be directly impacted by climate change and resulting biophysical effects. Here, we quantify these impacts until 2050 using GLOBIOM-Brazil, a global partial equilibrium model of the competition for land use between agriculture, forestry, and bioenergy that includes various refinements reflecting Brazil's specificities. For the first time, projections of future agricultural areas and production are based on future crop yields provided by two Global Gridded Crop Models (EPIC and LPJmL). The climate change forcing is included through changes in climatic variables projected by five Global Climate Models in two emission pathways (RCP2.6 and RCP8.5) participating in the ISIMIP initiative. This ensemble of twenty scenarios permits accessing the robustness of the results. When compared to the baseline scenario, GLOBIOM-Brazil scenarios suggest a decrease in soybeans and corn production, mainly in the Matopiba region in the Northern Cerrado, and southward displacement of agricultural production to near-subtropical and subtropical regions of the Cerrado and the Atlantic Forest biomes. Unlabelled Image • Projections of climate change impacts on main Brazilian agricultural commodities • Use of spatial explicit partial equilibrium global land use model adapted to Brazil • Framework integrating land-use competition and biophysical and economic aspects • Displacement of soybean and corn production toward subtropical regions of Brazil • Decrease in soybean and corn production, especially in the Matopiba region [ABSTRACT FROM AUTHOR]

• One of the services provided by tropical ecosystems is to help regulate extreme temperatures. • We apply a novel methodology to estimate the extreme-heat regulation value provided to agriculture by ecosystems in Brazil. • Lost soy revenue due to extreme heat from native vegetation loss reached an average of $99 (2005USD) ha−1 in 2012. • With agricultural growth and increased ecosystem conversion, the value of extreme heat regulation could grow 25% to 95% by 2050. • In some locales, the value of extreme heat regulation approaches the opportunity cost of conservation; in some places, it exceeds that cost. In tropical regions, widespread loss of native forest and savanna vegetation is increasing extreme heat, particularly in agricultural regions. Using the case of rising extreme heat from lost forest and savanna vegetation in Brazilian Amazon and Cerrado regions, we modeled losses to soy production, the region's principal economic activity. We assessed two types of extreme-heat regulation values: the value of avoided extreme-heat exposure of soy from the conservation of neighboring ecosystems and the value of lost revenue due to increased extreme heat exposure from increased ecosystem conversion. Our modeling combines empirical estimates of (1) the influence of ecosystem conversion on extreme heat over neighboring cropland, (2) the impacts of extreme heat on agricultural yields, and (3) native vegetation area, agricultural area, and crop prices. We examine lost soy value from land conversion over the period 1985 to 2012, potential losses from further conversion under plausible land and climate change scenarios (2020–2050), and the future value of conservation of the region's remaining ecosystem area near soy. Soy revenue lost due to extreme heat from native vegetation loss (1985–2012) totaled 99 (2005USD) ha−1 for 2012-2013 growing season. By 2050, agricultural growth, ecosystem conversion, and climate change could boost extreme-heat regulation values by 25% to 95%. Future values were strongly sensitive to changes in agricultural density, rates of native vegetation loss, and climate. Extreme-heat regulation values were largest in the Cerrado biome and the southeastern Amazon. Relative to land values, the value of extreme heat regulation was largest relative to the carbon value of biomass in the Cerrado. By regulating the exposure of agriculture to extreme heat, ecosystem conservation can create considerable value for the soy sector. [ABSTRACT FROM AUTHOR]