Steffen, WillRichardson, K.Rockstrom, J.Cornell, S. E.Fetzer, I.Bennett, E. M.Biggs, ReinetteCarpenter, S. R.de Vries, W.de Wit, C. A.Folke, C.Gerten, D.Heinke, J.Mace, G. M.Persson, L. M.Ramanathan, V.Reyers, B.Sorlin, S.2015-03-312015-03-310036-8075http://hdl.handle.net/1885/13126The planetary boundaries framework defines a safe operating space for humanity based on the intrinsic biophysical processes that regulate the stability of the Earth system. Here, we revise and update the planetary boundary framework, with a focus on the underpinning biophysical science, based on targeted input from expert research communities and on more general scientific advances over the past 5 years. Several of the boundaries now have a two-tier approach, reflecting the importance of cross-scale interactions and the regional-level heterogeneity of the processes that underpin the boundaries. Two core boundaries—climate change and biosphere integrity—have been identified, each of which has the potential on its own to drive the Earth system into a new state should they be substantially and persistently transgressed.The planetary boundaries research at the Stockholm Resilience Centre is made possible through a core grant from MISTRA (Swedish Foundation for Strategic Environmental Research). S.E.C. is supported by the Swedish Research Council, E.M.B. is supported by the Natural Sciences and Engineering Research Council of Canada and by the Trottier Institute for Science and Public Policy, R.B. is supported by a Branco Weiss Fellowship, C.F. is supported by the Family Erling Persson Academy Programme on Global Economic Dynamics and the Biosphere, I.F. is supported by the Stordalen Foundation (Norway), S.S. is supported by the Riksbanken Jubileumsfond and the Institute for Advanced Study, Princeton NJ, and S.R.C. and V.R. are supported by the U.S. National Science Foundation.10 pagesatmospherefresh waterhumansbiological evolutionclimate changeearth (planet)ozone depletionbiophysicsbiosphereboundary layerearth scienceheterogeneitystabilizationacidificationastronomyozone layerpriority journalevolution2015-02-1310.1126/science.12598552015-12-11