The amount of intact natural land as of 2018 was around 15% below this ESB, but could be increased through restoring degraded ecosystems or previously converted ecosystems,102,103,106102.Strassburg, BBN ∙ Iribarrem, A ∙ Beyer, HL ∙ et al.Global priority areas for ecosystem restorationNature. 2020; 586:724-729CrossrefScopus (536)PubMedGoogle Scholar103.Jung, M ∙ Arnell, A ∙ de Lamo, X ∙ et al.Areas of global importance for conserving terrestrial biodiversity, carbon and waterNat Ecol Evol. 2021; 5:1499-1509CrossrefScopus (162)PubMedGoogle Scholar106.Wolff, S ∙ Schrammeijer, EA ∙ Schulp, CJE ∙ et al.Meeting global land restoration and protection targets: what would the world look like in 2050?Glob Environ Change. 2018; 52:259-272CrossrefScopus (72)Google Scholar with conservation efforts distributed across all ecoregions.

We adopt the ‘3 Is of justice’: interspecies justice and Earth system stability; intergenerational justice (between past and present, and present and future); and intragenerational justice (between countries, communities and individuals). These principles derive from the seminal work of Weiss on intergenerational and intragenerational equity64, with additional focus on interspecies justice. In interspecies justice, we include justice that promotes Earth system stability to prevent the collapse of conditions of life for all species. We fold intercommunity, interstate and interindividual justice into a broad category of intragenerational justice, which includes concern for intersectional justice.

joint knowledge to identify safe and just ESBs

Cities exchange people, energy and goods with their local and global hinterlands9,10. Companies work with others across their value chains, near and far. Both interact with each other. We found that the top 200 cities with the largest greenhouse-gas emissions host the headquarters of 360 of the top 500 emitting companies. More than 50% of these cities and companies are in water-stressed areas, including Mexico City, Santiago, Beijing, Madrid, New Delhi, Rome, Istanbul in Turkey and Phoenix, Arizona.