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Semi-arid regions are known for erratic precipitation patterns with significant effects on the hydrological cycle and water resources availability. High temporal and spatial variation in precipitation causes large variability in runoff over short durations. Due to low soil water storage capacity, base flow is often missing and rivers fall dry for long periods. Because of its climatic characteristics, the semi-arid north-eastern region of Brazil is prone to droughts. To counter these, reservoirs were built to ensure water supply during dry months. This paper describes problems and solutions when calibrating and validating the eco-hydrological model SWIM for semi-arid regions on the example of the Pajeú watershed in north-eastern Brazil. The model was calibrated to river discharge data before the year 1983, with no or little effects of water management, applying a simple and an enhanced approach. Uncertainties result mainly from the meteorological data and observed river discharges. After model calibration water management was included in the simulations. Observed and simulated reservoir volumes and river discharges are compared. The calibrated and validated models were used to simulate the impacts of climate change on hydrological processes and water resources management using data of two representative concentration pathways (RCP) and five earth system models (ESM). The differences in changes in natural and managed mean discharges are negligible (< 5%) under RCP8.5 but notable (> 5%) under RCP2.6 for the ESM ensemble mean. In semi-arid catchments, the enhanced approach should be preferred, because in addition to discharge, a second variable, here evapotranspiration, is considered for model validation. [ABSTRACT FROM AUTHOR]

In recent decades, greater acknowledgement has been given to climate change as a cultural phenomenon. This paper takes a cultural lens to the topic of climate change, in which climate-relevant understandings are grounded in wider cultural, political and material contexts. We approach climate-relevant accounts at the level of the everyday, understood as a theoretically problematic and politically contested space This is in contrast to simply being the backdrop to mundane, repetitive actions contributing to environmental degradation and the site of mitigative actions. Taking discourse as a form of practice in which fragments of cultural knowledge are drawn on to construct our environmental problems, we investigate citizens' accounts of climate-relevant issues in three culturally diverse emerging economies: Brazil, South Africa and China. These settings are important because greenhouse gas (GHG) emissions are predicted to significantly increase in these countries in the future. We conducted semi-structured interviews with a range of citizens in each country using a narrative approach to contextualise climate-relevant issues as part of people's lifestyle narratives. Participants overwhelmingly framed their accounts in the context of locally-salient issues, and few accounts explicitly referred to the phenomenon of climate change. Instead, elements of climate changes were conflated with other environmental issues and related to a wide range of cultural assumptions that influenced understandings and implied particular ways of responding to environmental problems. We conclude that climate change scholars should address locally relevant understandings and develop dialogues that can wider meanings that construct climate-relevant issues in vernacular ways at the local level. [ABSTRACT FROM AUTHOR]

Transitioning from a carbon-intensive development path to a low-carbon economy requires understanding of emission sources and its drivers. To achieve Nationally Determined Contribution targets discussed under the Paris Agreement, countries must project emission baselines considering different levels of ambition and sectoral performances and monitor government policies and mitigation actions. This study develops a Monitoring, Reporting, and Verification (MRV) framework based on energy use and carbon emission scenarios for Brazil up to 2030, focusing on transport. Three scenarios are developed based on different political commitments. All scenarios and mitigation actions are discussed under the Brazilian Forum on Climate Change, which is recognized as one of the most important institutional instruments of the National Policy on Climate Change. Results reveal a 41% abatement in CO2e emissions when comparing the most ambitious scenario to the conservative one. MRV framework indicates that Brazil is on track to a low carbon economic transition, although joint action is needed. This is mainly due to the increasing penetration of bioenergy into the transport energy matrix, while electromobility does not expand in Brazil at the pace of major international players such as Europe and China. Special contribution of this paper is on the role of bioenergy in prospective carbon emission scenarios, which is a lack in the literature. [ABSTRACT FROM AUTHOR]

This paper measures the influence of climate normals (average long-term surface wetness and temperature) and interannual climate variance on farms in the United States and Brazil using satellite data. The paper finds that just climate normals or just climate variance variables can explain both net revenues and how much land is used for cropland. However, because they are correlated with each other, it is important to include both normals and variance in the same statistical model to get accurate measures of their individual contribution to farm outcomes. In general, higher climate variance increases the probability that land is used for cropland in both countries and higher temperatures reduce both cropland and land values. Other annual effects were not consistent across the two countries. [ABSTRACT FROM AUTHOR]

This paper updates the SCVI (Socio-Climatic Vulnerability Index) maps developed by Torres et al. () for Brazil, by using the new Coupled Model Intercomparison Project Phase 5 (CMIP5) projections and more recent 2010 social indicators data. The updated maps differ significantly from their earlier versions in two main ways. First, they show that heavily populated metropolitan areas - namely Belo Horizonte, Brasília, Salvador, Manaus, Rio de Janeiro and São Paulo - and a large swath of land across the states of São Paulo, Minas Gerais and Bahia now have the highest SCVI values, that is, their populations are the most vulnerable to climate change in the country. Second, SCVI values for Northeast Brazil are considerably lower compared to the previous index version. An analysis of the causes of such difference reveals that changes in climate projections between CMIP3 and CMIP5 are responsible for most of the change between the different SCVI values and spatial distribution, while changes in social indicators have less influence, despite recent countrywide improvements in social indicators as a result of aggressive anti-poverty programs. These results raise the hypothesis that social reform alone may not be enough to decrease people's vulnerability to future climatic changes. Whereas the coarse spatial resolution and relatively simplistic formulation of the SCVI may limit how useful these maps are at informing decision-making at the local level, they can provide a valuable input for large-scale policies on climate change adaptation such as those of the Brazilian National Policy on Climate Change Adaptation. [ABSTRACT FROM AUTHOR]

Several studies show that the El Niño-Southern Oscillation (ENSO) is an important factor in determining interannual rainfall variability in South America. This signal is detected in the region including Northeastern Argentina, Uruguay and part of southern Brazil, in the form of excessive rains and big floods in the regional rivers. To check that this relationship was similar in the past the objectives of this paper were to construct a time series of large floods in the Paraná River region from documentary records, during the sixteenth to eighteenth centuries, and to evaluate the relationship between that historical record of extreme floods, the ENSO documentary evidence (Ortlieb, The Documented Historical Record of El Niño Events in Perú: An Update of the Quinn Record (Ortlieb, sixteenth through nineteenth centuries, Diaz and Markgraf, (eds.), El Niño and the southern oscillation. Multiscale variability and global and regional Impacts. Cambridge University Press, pp. 207-295, 2001; Quinn and Neal, The historical record of El Niño events, Bradley and Jones (eds.), Climate since a.d. 1500, Routledges, pp. 623-648, 1992) and the temperature index of the Pacific Ocean (Mann ME et al., Global temperature patterns in past centuries: an interactive presentation, IGBP pages/world data center for paleoclimatology data contribution series #2000-075. NOAA/NGDC Paleoclimatology Program, Boulder CO, USA, 2000). Considering that the period 1904-2000, where 11 out of 16 floods occurred during El Niño events, it can be concluded that the proportion of years with exceptional flow volume in the Paraná River in years with El Niño events in the seventeenth and eighteenth centuries was relatively lower than that of the twentieth century. The reason for this difference is discussed. [ABSTRACT FROM AUTHOR]