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Consensus exists on the urgent need for food systems to be more sustainable, but defining their environmentally safe operating space is challenging. This study proposes food system boundaries as a share of planetary boundaries, defining budgets across nine boundaries and revealing where boundary transgression is most critical.

This study uses complex networks to identify atmospheric teleconnections driving summer heatwaves in the Northern Hemisphere. The results show that changes in certain teleconnections drive the spatial differences in heatwave variability and trends.

Climate change is expected to intensify the global hydrological cycle and to alter evapotranspiration, but direct observational constraints are lacking at the global scale. Now a data-driven, machine-learning technique and a suite of process-based models have been used to show that from 1982 to 1997 global evapotranspiration increased by about 7.1 millimetres per year per decade. But since 1998 this increase has ceased, probably because of moisture limitation in the Southern Hemisphere.

Determining the safe operating space for sustainable food production depends on the interactions of multiple processes within the Earth system. Expert knowledge provides critical insight into how these processes interact that improves Earth system modelling and our understanding of the limits of global food production.

Exceptional streamflow and soil moisture conditions now occur on a substantial share of global land area and are much more frequent than in pre-industrial times. This marks a notable transgression of the new planetary boundary for freshwater change.

Agriculture transforms the Earth and risks crossing thresholds for a healthy planet. This study finds almost half of current food production crosses such boundaries, as for freshwater use, but that transformation towards more sustainable production and consumption could support 10.2 billion people.

Anthropogenic pressures and climate change are altering water flows worldwide. Better understanding, new economic thinking and an international governance framework are needed to stave off catastrophe.

Significant regional disparities exist in the time left to prepare for unprecedented drought and how much we can buy time depending on climate scenarios. Specific regions pass this timing by the middle of 21st century even with stringent mitigation.

Projections of terrestrial water storage (TWS)—the sum of all continental water—are key to water resource and drought estimates. A hydrological model ensemble predicts climate warming will more than double the land area and population exposed to extreme TWS drought by the late twenty-first century.

The authors here model how water stress would be affected either by biomass plantations combined with carbon capture and storage (BECCS) in a strong climate mitigation scenario (1.5 °C warming in 2100) or by climate impacts in a strong climate change scenario (3 °C warming in 2100).

Impact models projections are used in integrated assessments of climate change. Here the authors test systematically across many important systems, how well such impact models capture the impacts of extreme climate conditions.

Sustainable development goals for water use and food production are in conflict, but this could be reduced by proper water management. Here, violations of global environmental flow requirements for rivers are quantified and related to reconciliation potentials in irrigated and rainfed agriculture.

The cascading effects and feedbacks of interactions between planetary boundaries shrink the safe operating space originally identified by analysing each boundary separately.

Climate oscillations such as El Niño Southern Oscillation may impact global crop production. Here, the authors, using a unified framework of multiple climate oscillations, find that from 1961 to 2010 over two-thirds of the global cropland is located where crop productivity is influenced by climate oscillations.

Biomass-based negative emissions can help to address the planetary boundary (PB) for climate change. However, side-effects likely include pushing us closer to the PBs for freshwater use and further transgression of the PBs for biosphere integrity, land-system change, and biogeochemical flows.

Increasing atmospheric CO₂ concentrations are expected to enhance photosynthesis and reduce plant water use. Research now reveals regional disparities in this effect on crops, with potential implications for food production and water consumption.

Climate change mitigation through biomass crops for carbon capture and storage outside agricultural land is strongly limited when considering other critical Earth system dimensions, such as biosphere integrity and land-system change, as global biogeochemical modelling shows.

The planetary boundaries framework outlines a safe operating space for humanity according to key Earth system dynamics. This Perspective proposes the addition of a green water planetary boundary based on root-zone soil moisture and demonstrates that widespread green water modifications now present increasing risks to Earth system resilience.