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Tropical deforestation in Brazil is a major source of greenhouse gas emissions that contribute to climate change. Brazil has taken several steps to reduce emissions associated with deforestation including the development of policies to promote and reward cattle ranching intensification. Intensification practices are hypothesized to reduce the conversion of tropical forests while simultaneously increasing the productivity of ranching on current pasture lands. This paper assesses the impact of intensification on the demand for productive land. A theoretical model of land use, which considers the degree of intensification in the estimation of the derived demand for pasture, is tested with data from small-scale landowners who operate dairy farms and calving operations in the greater Ouro Preto do Oeste region of Rondônia. Results suggest different trajectories for beef and dairy production. The intensification of cattle production exhibits a nonlinear relationship with the demand for productive land: first as farms become more intensive the demand for newly cleared land increases, but then decreases with further intensification. The results are different for dairy intensification, which is found to be correlated with reduced deforestation. Findings suggest that the reliance on policies that promote intensification can be a risky way of achieving climate change objectives. [ABSTRACT FROM AUTHOR]

Assessing the relative contribution of Land Use and Cover Changes (LUCC) and climate changes on runoff still represents a great challenge for water resources management. This issue is particularly critical for the Upper Paraná River Basin (UPRB), one of the most important basins in South America and responsible for most of the production of food, ethanol, and electricity generation in Brazil. In this paper, we used the Soil and Water Assessment Tool (SWAT) to quantitatively assess the relative contribution of both forcings. The simulation period included a time of great importance for climate studies, known as the 1970s global climate shift, and of great impact on river discharge within the UPRB. Three land use and cover scenarios were assigned to the 1961–1990 period of simulations, representing land use and cover during a pristine period (around the Year 1500), 1960, and 1985. Thirteen years of precipitation before and after the climate shift (considered to be the period 1974–1977) were analyzed and compared. Results showed a precipitation increase for the basin in general after the climate shift. The increase in rainfall reached up to 15% in many northern areas and more than 20% in the southern parts of the basin. By comparing all simulations, results indicate that both LUCC and precipitation increase due to the climate shift had a significant effect on the changes in annual discharge of the largest rivers of the UPRB. However, the results suggest that the impact of the precipitation increase on the discharge exceeded that of the LUCC. Between 1960 and 1985 the LUCC accounts for about 16% of the increase of the median annual discharge, whereas climate shift accounts for an increase of about 32%. These findings, suggesting a more relevant role for the climate, are consistent with two recent water crisis experienced by the country in the last decades, caused by prolonged below-normal rainfall throughout 2001/2002 and again in 2014/2015. [Display omitted] • We simulated land use and cover from a pristine period (Year 1500), 1960, and 1985. • We evaluated the effects of precipitation change on discharge from 1961 to 1990. • Natural vegetation fell by more than half of the original area up to 1985. • Precipitation increased by more than 20% after the 1970s global climate shift. • Results suggest that climate shift is the main driver in increasing annual discharge. [ABSTRACT FROM AUTHOR]

There is an urgent need for more information about the climate change impact on health in order to strengthen the commitment to tackle climate change. However, few studies have quantified the health impact of climate change in Brazil and in the Latin America region. In this paper, we projected the impacts of temperature on cardiovascular (CVD) mortality according to two climate change scenarios and two regionalized climate model simulations in Brazilian cities. We estimated the temperature-CVD mortality relationship in 21 Brazilian cities, using distributed lag non-linear models in a two-stage time-series analysis. We combined the observed exposure-response functions with the daily temperature projected under two representative concentration pathways (RCP), RCP8.5 and RCP4.5, and two regionalized climate model simulations, Eta-HadGEM2-ES and Eta-MIROC5. We observed a trend of reduction in mortality related to low temperatures and a trend of increase in mortality related to high temperatures, according to all the investigated models and scenarios. In most places, the increase in mortality related to high temperatures outweighed the reduction in mortality related to low temperatures, causing a net increase in the excess temperature-related mortality. These trends were steeper according to the higher emission scenario, RCP8.5, and to the Eta-HadGEM2-ES model. According to RCP8.5, our projections suggested that the temperature-related mortality fractions in 2090-99 compared to 2010–2019 would increase by 8.6% and 1.7%, under Eta-HadGEM2-ES and Eta-MIROC5, respectively. According to RCP4.5, these values would be 0.7% and −0.6%. For the same climate model, we observed a greater increase trend in temperature-CVD mortality according to RCP8.5, highlighting a greater health impact associated with the higher emission scenario. Our results may be useful to support public policies and strategies for mitigation of and adaptation to climate change, particularly in the health sector. • We estimated climate change impacts on temperature-CVD mortality in Brazil. • The projections showed a reduction in CVD mortality related to low temperatures. • The projections showed an increase in CVD mortality related to high temperatures. • We found a net increase in temperature-related mortality in most cities. • A greater health impact was associated with the higher emission scenario. [ABSTRACT FROM AUTHOR]