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Over the past 50 years, humans have extracted the Earth’s groundwater stocks at a steep rate, largely to fuel global agro-economic development. Given society’s growing reliance on groundwater, we explore ‘peak water limits’ to investigate whether, when and where humanity might reach peak groundwater extraction. Using an integrated global model of the coupled human–Earth system, we simulate groundwater withdrawals across 235 water basins under 900 future scenarios of global change over the twenty-first century. Here we find that global non-renewable groundwater withdrawals exhibit a distinct peak-and-decline signature, comparable to historical observations of other depletable resources (for example, minerals), in nearly all (98%) scenarios, peaking on average at 625 km3 yr−1 around mid-century, followed by a decline through 2100. The peak and decline occur in about one-third (82) of basins, including 21 that may have already peaked, exposing about half (44%) of the global population to groundwater stress. Most

Energy return on investment (EROI) is a biophysical and ecological economics concept that is useful to think about how organisms, ecosystems and societies must obtain enough surplus energy returned from energy gathering activities to live, reproduce, and thrive. EROI can help us overcome the false dualism between nature and society. EROI is a useful metric for economics because it is based on immutable physical laws rather than sometimes arbitrary human preferences. It is essential for assessing useful power, energy trade-offs, efficiencies (and inefficiencies), resource depletion trends, resource quality, and surplus potentials of different fuels and technologies that power, or might power, our socio-economic systems. Apparent inconsistencies in the literature can generally be reduced or eliminated by paying careful attention and explicitly stating boundaries and definitions. We argue that proper use of EROI is critical to understand the interconnections among the environment, energy, and socio-economic deve

Human activity is putting the Earth on a trajectory towards environmental collapse. The SDGs were adopted in2015 to reconcile human activity with planetary boundaries. So far, the SDGs have not lived up to their promise in European Union member states. Most EU countries have seen socioeconomic development alongside environmental degradation. Progress towards environmental sustainability only occurs in countries with slow or negative socioeconomic trends.

Metals will play a central role in successfully building Europe’s clean technology value chains and meeting the EU’s 2050 climate-neutrality goal. In the wake of supply disruptions from the COVID-19 pandemic and Russia's invasion of Ukraine, Europe’s lack of resilience for its growing metals needs has become a strategic concern. This study evaluates how Europe can fulfil its goal of “achieving resource security” and “reducing strategic dependencies” for its energy transition metals, through a demand, supply, and sustainability assessment of the EU Green Deal and its resource needs . It concludes that Europe has a window of opportunity to lay the foundation for a higher level of strate- gic autonomy and sustainability for its strategic metals through optimised recycling, domestic value chain investment, and more active global sourcing. But firm action is needed soon to avoid bottlenecks for several materials that risk being in global short supply at the end of this decade.

An extensive new multi-proxy database of paleo-temperature time series (Temperature 12k) enables a more robust analysis of global mean surface temperature (GMST) and associated uncertainties than was previously available. We applied five different statistical methods to reconstruct the GMST of the past 12,000 years (Holocene). Each method used different approaches to averaging the globally distributed time series and to characterizing various sources of uncertainty, including proxy temperature, chronology and methodological choices. The results were aggregated to generate a multi-method ensemble of plausible GMST and latitudinal-zone temperature reconstructions with a realistic range of uncertainties. The warmest 200-year-long interval took place around 6500 years ago when GMST was 0.7 °C (0.3, 1.8) warmer than the 19th Century (median, 5th, 95th percentiles). Following the Holocene global thermal maximum, GMST cooled at an average rate −0.08 °C per 1000 years (−0.24, −0.05). The multi-method ensembles and th

Is it possible to enjoy both economic growth and environmental sustainability? This question is a matter of fierce political debate between green growth and post-growth advocates. Considering what is at stake, a careful assessment to determine whether the scientific foundations behind this decoupling hypothesis are robust or not is needed.

Freshwater availability is changing worldwide. Here we quantify 34 trends in terrestrial water storage observed by the Gravity Recovery and Climate Experiment (GRACE) satellites during 2002–2016 and categorize their drivers as natural interannual variability, unsustainable groundwater consumption, climate change or combinations thereof. Several of these trends had been lacking thorough investigation and attribution, including massive changes in northwestern China and the Okavango Delta. Others are consistent with climate model predictions. This observation-based assessment of how the world’s water landscape is responding to human impacts and climate variations provides a blueprint for evaluating and predicting emerging threats to water and food security. Analysis of 2002–2016 GRACE satellite observations of terrestrial water storage reveals substantial changes in freshwater resources globally, which are driven by natural and anthropogenic climate variability and human activities.