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- ItemHarmonization of global land use change and management for the period 850–2100 (LUH2) for CMIP6(Katlenburg-Lindau : Copernicus, 2020) Hurtt, George C.; Chini, Louise; Sahajpal, Ritvik; Frolking, Steve; Bodirsky, Benjamin L.; Calvin, Katherine; Doelman, Jonathan C.; Fisk, Justin; Fujimori, Shinichiro; Klein Goldewijk, Kees; Hasegawa, Tomoko; Havlik, Peter; Heinimann, Andreas; Humpenöder, Florian; Jungclaus, Johan; Kaplan, Jed O.; Kennedy, Jennifer; Krisztin, Tamás; Lawrence, David; Lawrence, Peter; Ma, Lei; Mertz, Ole; Pongratz, Julia; Popp, Alexander; Poulter, Benjamin; Riahi, Keywan; Shevliakova, Elena; Stehfest, Elke; Thornton, Peter; Tubiello, Francesco N.; van Vuuren, Detlef P.; Zhang, XinHuman land use activities have resulted in large changes to the biogeochemical and biophysical properties of the Earth's surface, with consequences for climate and other ecosystem services. In the future, land use activities are likely to expand and/or intensify further to meet growing demands for food, fiber, and energy. As part of the World Climate Research Program Coupled Model Intercomparison Project (CMIP6), the international community has developed the next generation of advanced Earth system models (ESMs) to estimate the combined effects of human activities (e.g., land use and fossil fuel emissions) on the carbon–climate system. A new set of historical data based on the History of the Global Environment database (HYDE), and multiple alternative scenarios of the future (2015–2100) from Integrated Assessment Model (IAM) teams, is required as input for these models. With most ESM simulations for CMIP6 now completed, it is important to document the land use patterns used by those simulations. Here we present results from the Land-Use Harmonization 2 (LUH2) project, which smoothly connects updated historical reconstructions of land use with eight new future projections in the format required for ESMs. The harmonization strategy estimates the fractional land use patterns, underlying land use transitions, key agricultural management information, and resulting secondary lands annually, while minimizing the differences between the end of the historical reconstruction and IAM initial conditions and preserving changes depicted by the IAMs in the future. The new approach builds on a similar effort from CMIP5 and is now provided at higher resolution (0.25∘×0.25∘) over a longer time domain (850–2100, with extensions to 2300) with more detail (including multiple crop and pasture types and associated management practices) using more input datasets (including Landsat remote sensing data) and updated algorithms (wood harvest and shifting cultivation); it is assessed via a new diagnostic package. The new LUH2 products contain > 50 times the information content of the datasets used in CMIP5 and are designed to enable new and improved estimates of the combined effects of land use on the global carbon–climate system.
- ItemA protocol for an intercomparison of biodiversity and ecosystem services models using harmonized land-use and climate scenarios(Katlenburg-Lindau : Copernicus, 2018) Kim, HyeJin; Rosa, Isabel M. D.; Alkemade, Rob; Leadley, Paul; Hurtt, George; Popp, Alexander; van Vuuren, Detlef P.; Anthoni, Peter; Arneth, Almut; Baisero, Daniele; Caton, Emma; Chaplin-Kramer, Rebecca; Chini, Louise; De Palma, Adriana; Di Fulvio, Fulvio; Di Marco, Moreno; Espinoza, Felipe; Ferrier, Simon; Fujimori, Shinichiro; Gonzalez, Ricardo E.; Gueguen, Maya; Guerra, Carlos; Harfoot, Mike; Harwood, Thomas D.; Hasegawa, Tomoko; Haverd, Vanessa; HavlÃk, Petr; Hellweg, Stefanie; Hill, Samantha L. L.; Hirata, Akiko; Hoskins, Andrew J.; Janse, Jan H.; Jetz, Walter; Johnson, Justin A.; Krause, Andreas; Leclère, David; Martins, Ines S.; Matsui, Tetsuya; Merow, Cory; Obersteiner, Michael; Ohashi, Haruka; Poulter, Benjamin; Purvis, Andy; Quesada, Benjamin; Rondinini, Carlo; Schipper, Aafke M.; Sharp, Richard; Takahashi, Kiyoshi; Thuiller, Wilfried; Titeux, Nicolas; Visconti, Piero; Ware, Christopher; Wolf, Florian; Pereira, Henrique M.To support the assessments of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), the IPBES Expert Group on Scenarios and Models is carrying out an intercomparison of biodiversity and ecosystem services models using harmonized scenarios (BES-SIM). The goals of BES-SIM are (1) to project the global impacts of land-use and climate change on biodiversity and ecosystem services (i.e., nature's contributions to people) over the coming decades, compared to the 20th century, using a set of common metrics at multiple scales, and (2) to identify model uncertainties and research gaps through the comparisons of projected biodiversity and ecosystem services across models. BES-SIM uses three scenarios combining specific Shared Socio-economic Pathways (SSPs) and Representative Concentration Pathways (RCPs)-SSP1xRCP2.6, SSP3xRCP6.0, SSP5xRCP8.6-to explore a wide range of land-use change and climate change futures. This paper describes the rationale for scenario selection, the process of harmonizing input data for land use, based on the second phase of the Land Use Harmonization Project (LUH2), and climate, the biodiversity and ecosystem services models used, the core simulations carried out, the harmonization of the model output metrics, and the treatment of uncertainty. The results of this collaborative modeling project will support the ongoing global assessment of IPBES, strengthen ties between IPBES and the Intergovernmental Panel on Climate Change (IPCC) scenarios and modeling processes, advise the Convention on Biological Diversity (CBD) on its development of a post-2020 strategic plans and conservation goals, and inform the development of a new generation of nature-centred scenarios.
- ItemEstimating global land system impacts of timber plantations using MAgPIE 4.3.5(Katlenburg-Lindau : Copernicus, 2021) Mishra, Abhijeet; Humpenoeder, Florian; Dietrich, Jan Philipp; Bodirsky, Benjamin Leon; Sohngen, Brent; Reyer, Christopher P. O.; Lotze-Campen, Hermann; Popp, AlexanderOut of 1150 Mha (million hectares) of forest designated primarily for production purposes in 2020, plantations accounted for 11 % (131 Mha) of this area and fulfilled more than 33 % of the global industrial roundwood demand. However, adding additional timber plantations to meet increasing timber demand intensifies competition for scarce land resources between different land uses such as food, feed, livestock and timber production. Despite the significance of plantations with respect to roundwood production, their importance in meeting the long-term timber demand and the implications of plantation expansion for overall land-use dynamics have not been studied in detail, in particular regarding the competition for land between agriculture and forestry in existing land-use models. This paper describes the extension of the modular, open-source land system Model of Agricultural Production and its Impact on the Environment (MAgPIE) using a detailed representation of forest land, timber production and timber demand dynamics. These extensions allow for a better understanding of the land-use dynamics (including competition for land) and the associated land-use change emissions of timber production. We show that the spatial cropland patterns differ when timber production is accounted for, indicating that timber plantations compete with cropland for the same scarce land resources. When plantations are established on cropland, it causes cropland expansion and deforestation elsewhere. Using the exogenous extrapolation of historical roundwood production from plantations, future timber demand and plantation rotation lengths, we model the future spatial expansion of forest plantations. As a result of increasing timber demand, we show a 177 % increase in plantation area by the end of the century (+171 Mha in 1995–2100). We also observe (in our model results) that the increasing demand for timber amplifies the scarcity of land, which is indicated by shifting agricultural land-use patterns and increasing yields from cropland compared with a case without forestry. Through the inclusion of new forest plantation and natural forest dynamics, our estimates of land-related CO2 emissions better match with observed data, in particular the gross land-use change emissions and carbon uptake (via regrowth), reflecting higher deforestation with the expansion of managed land and timber production as well as higher regrowth in natural forests and plantations.
- ItemGlobal emissions pathways under different socioeconomic scenarios for use in CMIP6: a dataset of harmonized emissions trajectories through the end of the century(Katlenburg-Lindau : Copernicus, 2019) Gidden, Matthew J.; Riahi, Keywan; Smith, Steven J.; Fujimori, Shinichiro; Luderer, Gunnar; Kriegler, Elmar; van Vuuren, Detlef P.; van den Berg, Maarten; Feng, Leyang; Klein, David; Calvin, Katherine; Doelman, Jonathan C.; Frank, Stefan; Fricko, Oliver; Harmsen, Mathijs; Hasegawa, Tomoko; Havlik, Petr; Hilaire, Jérôme; Hoesly, Rachel; Horing, Jill; Popp, Alexander; Stehfest, Elke; Takahashi, KiyoshiWe present a suite of nine scenarios of future emissions trajectories of anthropogenic sources, a key deliverable of the ScenarioMIP experiment within CMIP6. Integrated assessment model results for 14 different emissions species and 13 emissions sectors are provided for each scenario with consistent transitions from the historical data used in CMIP6 to future trajectories using automated harmonization before being downscaled to provide higher emissions source spatial detail. We find that the scenarios span a wide range of end-of-century radiative forcing values, thus making this set of scenarios ideal for exploring a variety of warming pathways. The set of scenarios is bounded on the low end by a 1.9 W m−2 scenario, ideal for analyzing a world with end-of-century temperatures well below 2 ∘C, and on the high end by a 8.5 W m−2 scenario, resulting in an increase in warming of nearly 5 ∘C over pre-industrial levels. Between these two extremes, scenarios are provided such that differences between forcing outcomes provide statistically significant regional temperature outcomes to maximize their usefulness for downstream experiments within CMIP6. A wide range of scenario