2019, Luderer, Gunnar, Pehl, Michaja, Arvesen, Anders, Gibon, Thomas, Bodirsky, Benjamin L., de Boer, Harmen Sytze, Fricko, Oliver, Hejazi, Mohamad, Humpenöder, Florian, Iyer, Gokul, Mima, Silvana, Mouratiadou, Ioanna, Pietzcker, Robert C., Popp, Alexander, van den Berg, Maarten, van Vuuren, Detlef, Hertwich, Edgar G.

A rapid and deep decarbonization of power supply worldwide is required to limit global warming to well below 2 °C. Beyond greenhouse gas emissions, the power sector is also responsible for numerous other environmental impacts. Here we combine scenarios from integrated assessment models with a forward-looking life-cycle assessment to explore how alternative technology choices in power sector decarbonization pathways compare in terms of non-climate environmental impacts at the system level. While all decarbonization pathways yield major environmental co-benefits, we find that the scale of co-benefits as well as profiles of adverse side-effects depend strongly on technology choice. Mitigation scenarios focusing on wind and solar power are more effective in reducing human health impacts compared to those with low renewable energy, while inducing a more pronounced shift away from fossil and toward mineral resource depletion. Conversely, non-climate ecosystem damages are highly uncertain but tend to increase, chiefly due to land requirements for bioenergy.

2021, Mouratiadou, Ioanna, Latka, Catharina, van der Hilst, Floor, Müller, Christoph, Berges, Regine, Bodirsky, Benjamin Leon, Ewert, Frank, Faye, Babacar, Heckelei, Thomas, Hoffmann, Munir, Lehtonen, Heikki, Lorite, Ignacio Jesus, Nendel, Claas, Palosuo, Taru, Rodríguez, Alfredo, Rötter, Reimund Paul, Ruiz-Ramos, Margarita, Stella, Tommaso, Webber, Heidi, Wicke, Birka

Sustainable intensification (SI) of agriculture is a promising strategy for boosting the capacity of the agricultural sector to meet the growing demands for food and non-food products and services in a sustainable manner. Assessing and quantifying the options for SI remains a challenge due to its multiple dimensions and potential associated trade-offs. We contribute to overcoming this challenge by proposing an approach for the ex-ante evaluation of SI options and trade-offs to facilitate decision making in relation to SI. This approach is based on the utilization of a newly developed SI metrics framework (SIMeF) combined with agricultural systems modelling. We present SIMeF and its operationalization approach with modelling and evaluate the approach’s feasibility by assessing to what extent the SIMeF metrics can be quantified by representative agricultural systems models. SIMeF is based on the integration of academic and policy indicator frameworks, expert opinions, as well as the Sustainable Development Goals. Structured along seven SI domains and consisting of 37 themes, 142 sub-themes and 1128 metrics, it offers a holistic, generic, and policy-relevant dashboard for selecting the SI metrics to be quantified for the assessment of SI options in diverse contexts. The use of SIMeF with agricultural systems modelling allows the ex-ante assessment of SI options with respect to their productivity, resource use efficiency, environmental sustainability and, to a large extent, economic sustainability. However, we identify limitations to the use of modelling to represent several SI aspects related to social sustainability, certain ecological functions, the multi-functionality of agriculture, the management of losses and waste, and security and resilience. We suggest advancements in agricultural systems models and greater interdisciplinary and transdisciplinary integration to improve the ability to quantify SI metrics and to assess trade-offs across the various dimensions of SI.

2017, Frieler, Katja, Lange, Stefan, Piontek, Franziska, Reyer, Christopher P.O., Schewe, Jacob, Warszawski, Lila, Zhao, Fang, Chini, Louise, Denvil, Sebastien, Emanuel, Kerry, Geiger, Tobias, Halladay, Kate, Hurtt, George, Mengel, Matthias, Murakami, Daisuke, Ostberg, Sebastian, Popp, Alexander, Riva, Riccardo, Stevanovic, Miodrag, Suzuki, Tatsuo, Volkholz, Jan, Burke, Eleanor, Ciais, Philippe, Ebi, Kristie, Eddy, Tyler D., Elliott, Joshua, Galbraith, Eric, Gosling, Simon N., Hattermann, Fred, Hickler, Thomas, Hinkel, Jochen, Hof, Christian, Huber, Veronika, Jägermeyr, Jonas, Krysanova, Valentina, Marcé, Rafael, Müller Schmied, Hannes, Mouratiadou, Ioanna, Pierson, Don, Tittensor, Derek P., Vautard, Robert, van Vliet, Michelle, Biber, Matthias F., Betts, Richard A., Bodirsky, Benjamin Leon, Deryng, Delphine, Frolking, Steve, Jones, Chris D., Lotze, Heike K., Lotze-Campen, Hermann, Sahajpal, Ritvik, Thonicke, Kirsten, Tian, Hanqin, Yamagata, Yoshiki

In Paris, France, December 2015, the Conference of the Parties (COP) to the United Nations Framework Convention on Climate Change (UNFCCC) invited the Intergovernmental Panel on Climate Change (IPCC) to provide a "special report in 2018 on the impacts of global warming of 1.5°C above pre-industrial levels and related global greenhouse gas emission pathways". In Nairobi, Kenya, April 2016, the IPCC panel accepted the invitation. Here we describe the response devised within the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP) to provide tailored, cross-sectorally consistent impact projections to broaden the scientific basis for the report. The simulation protocol is designed to allow for (1) separation of the impacts of historical warming starting from pre-industrial conditions from impacts of other drivers such as historical land-use changes (based on pre-industrial and historical impact model simulations); (2) quantification of the impacts of additional warming up to 1.5°C, including a potential overshoot and long-term impacts up to 2299, and comparison to higher levels of global mean temperature change (based on the low-emissions Representative Concentration Pathway RCP2.6 and a no-mitigation pathway RCP6.0) with socio-economic conditions fixed at 2005 levels; and (3) assessment of the climate effects based on the same climate scenarios while accounting for simultaneous changes in socio-economic conditions following the middle-of-the-road Shared Socioeconomic Pathway (SSP2, Fricko et al., 2016) and in particular differential bioenergy requirements associated with the transformation of the energy system to comply with RCP2.6 compared to RCP6.0. With the aim of providing the scientific basis for an aggregation of impacts across sectors and analysis of cross-sectoral interactions that may dampen or amplify sectoral impacts, the protocol is designed to facilitate consistent impact projections from a range of impact models across different sectors (global and regional hydrology, lakes, global crops, global vegetation, regional forests, global and regional marine ecosystems and fisheries, global and regional coastal infrastructure, energy supply and demand, temperature-related mortality, and global terrestrial biodiversity).

2016, Kriegler, Elmar, Bauer, Nico, Popp, Alexander, Humpenöder, Florian, Leimbach, Marian, Strefler, Jessica, Baumstark, Lavinia, Bodirsky, Benjamin Leon, Hilaire, Jérôme, Klein, David, Mouratiadou, Ioanna, Weindl, Isabelle, Bertram, Christoph, Dietrich, Jan-Philipp, Luderer, Gunnar, Pehl, Michaja, Pietzcker, Robert, Piontek, Franziska, Lotze-Campen, Hermann, Biewald, Anne, Bonsch, Markus, Giannousakis, Anastasis, Kreidenweis, Ulrich, Müller, Christoph, Rolinski, Susanne, Schultes, Anselm, Schwanitz, Jana, Stevanovic, Miodrag, Calvin, Katherine, Emmerling, Johannes, Fujimori, Shinichiro, Edenhofer, Ottmar

This paper presents a set of energy and resource intensive scenarios based on the concept of Shared Socio-Economic Pathways (SSPs). The scenario family is characterized by rapid and fossil-fueled development with high socio-economic challenges to mitigation and low socio-economic challenges to adaptation (SSP5). A special focus is placed on the SSP5 marker scenario developed by the REMIND-MAgPIE integrated assessment modeling framework. The SSP5 baseline scenarios exhibit very high levels of fossil fuel use, up to a doubling of global food demand, and up to a tripling of energy demand and greenhouse gas emissions over the course of the century, marking the upper end of the scenario literature in several dimensions. These scenarios are currently the only SSP scenarios that result in a radiative forcing pathway as high as the highest Representative Concentration Pathway (RCP8.5). This paper further investigates the direct impact of mitigation policies on the SSP5 energy, land and emissions dynamics confirming high socio-economic challenges to mitigation in SSP5. Nonetheless, mitigation policies reaching climate forcing levels as low as in the lowest Representative Concentration Pathway (RCP2.6) are accessible in SSP5. The SSP5 scenarios presented in this paper aim to provide useful reference points for future climate change, climate impact, adaption and mitigation analysis, and broader questions of sustainable development.