• Energy Research

This paper presents an analysis of climate policy instruments for the decarbonisation of the global electricity sector in a non-equilibrium economic and technology diffusion perspective. Energy markets are driven by innovation, path-dependent technology choices and diffusion. However, conventional optimisation models lack detail on these aspects and have limited ability to address the effectiveness of policy interventions because they do not represent decision-making. As a result, known effects of technology lock-ins are liable to be underestimated. In contrast, our approach places investor decision-making at the core of the analysis and investigates how it drives the diffusion of low-carbon technology in a highly disaggregated, hybrid, global macroeconometric model, FTT:Power-E3MG. Ten scenarios to 2050 of the electricity sector in 21 regions exploring combinations of electricity policy instruments are analysed, including their climate impacts. We show that in a diffusion and path-dependent perspective, the impact of combinations of policies does not correspond to the sum of impacts of individual instruments: synergies exist between policy tools. We argue that the carbon price required to break the current fossil technology lock-in can be much lower when combined with other policies, and that a 90% decarbonisation of the electricity sector by 2050 is affordable without early scrapping. 18 pages, 6 figures, 3 appendices

Simulating South American biodiversity The emergence, distribution, and extinction of species are driven by interacting factors—spatial, temporal, physical, and biotic. Rangel et al. simulated the past 800,000 years of evolution in South America, incorporating these factors into a spatially explicit dynamic model to explore the geographical generation of diversity. Their simulations, based on a paleoclimate model on a 5° latitude-longitude scale, result in shifting maps of speciation, persistence, and extinction (or cradles, museums, and graves). The simulations culminate in a striking resemblance to contemporary distribution patterns across the continent for birds, mammals, and plants—despite having no target patterns and no empirical data parameterizing them. Science , this issue p. eaar5452

The Energy-Water-Food Nexus is one of the most complex sustainability challenges faced by the world. This is particularly true in Brazil, where insufficiently understood interactions within the Nexus are contributing to large-scale deforestation and land-use change, water and energy scarcity, and increased vulnerability to climate change. The reason is a combination of global environmental change and global economic change, putting un- precedented pressures on the Brazilian environment and ecosystems. In this paper, we identify and discuss the main Nexus challenges faced by Brazil across sectors (e.g. energy, agriculture, water) and scales (e.g. federal, state, municipal). We use four case studies to explore all nodes of the Nexus. For each, we analyse data from economic and biophysical modelling sources in combination with an overview of the legislative and policy landscape, in order to identify governance shortcomings in the context of growing challenges. We analyse the complex interdependence of developments at the global and local (Brazilian) levels, highlighting the impact of global environmental and economic change on Brazil and, conversely, that of developments in Brazil for other countries and the world. We conclude that there is a need to adjust the scientific approach to these challenges as an enabling condition for stronger science-policy bridges for sustainability policy-making.

For each 500-year time interval from 800 Ka (years ago) to the present (1600 time steps), we used a paleoclimate model to assign to each of the 4820 map cells an estimate of the mean temperature of the warmest and coolest quarters and the mean daily precipitation of the wettest and driest quarters. These four factors, on two environmental axes (annual temperature and annual precipitation) characterize the changing climate in each grid cell over the time-course of the simulation.The database consists of the paleoclimate data used in this simulation. It is composed of one text file for each climate variable: (1) minimum annual precipitation, (2) maximum annual precipitation, (3) minimum annual temperature, and (4) maximum annual temperature. Within each file, each row represents a single map cell (4820 in total). The first two columns are the geographical coordinates of each grid cell (latitude and longitude in decimal degrees). The succeeding columns describe the climate variable at each time slice of the series, at successive 500-year intervals. Each column is labeled Tx, where x is thousands of years before present. For example, column “T795.5” of file “PrecipAvgAnnualMax.txt” contains the map cell data for maximum annual precipitation at 795.5kya. Supplement to: Rangel, Thiago F; Edwards, Neil R; Holden, Philip B; Diniz-Filho, José Alexandre F; Gosling, William D; Coelho, Marco Túlio P; Cassemiro, Fernanda A S; Rahbek, Carsten; Colwell, Robert K (2018): Modeling the ecology and evolution of biodiversity: Biogeographical cradles, museums, and graves. Science, 361(6399), eaar5452

Data and code related to: Gosling, W.D., Miller, C.S., Shanahan, T.M., Holden, P.B., Overpeck, J.T. & van Langevelde, F. (2022) A stronger role for long-term moisture change than for CO2 in determining tropical woody vegetation change. Science. DOI: 10.1126/science.abg4618 https://doi.org/10.1126/science.abg4618 Including: - Chronology for Lake Bosumtwi 5B sediment core raised by the Intercontinental Drilling Program (ICDP) in 2004. - Pollen, charcoal, Spororomiella and nitrogen isotope data from sub-samples extracted from the 5B sediment core. - Model outputs from the GENIE-1 climate-carbon storage model. - Interpolated datasets. - R code used to run structural equation models. Data and code related to: Gosling, W.D., Miller, C.S., Shanahan, T.M., Holden, P.B., Overpeck, J.T. & van Langevelde, F. (2022) A stronger role for long-term moisture change than for CO2 in determining tropical woody vegetation change. Including: - Chronology for Lake Bosumtwi 5B sediment core raised by the Intercontinental Drilling Program (ICDP) in 2004. Pollen, charcoal, Spororomiella and nitrogen isotope data from sub-samples extracted from the 5B sediment core. - Model outputs from the GENIE-1 climate-carbon storage model. - Interpolated datasets. - R code used to run structural equation models.