Communications Earth & Environment最新文献

Extreme flooding and prolonged, intensifying droughts have played a critical role in the rise and collapse of preindustrial states and empires worldwide, triggering cascading impacts such as crop failure, famine, and migration that undermined socio-political stability and economic resilience. We present a multicomponent hydroclimatic vulnerability model for crop supply networks to estimate the contribution of climatic stressors as one of several factors contributing to the decline of the late Tang Dynasty in northern China between 800 and 907 CE. We demonstrate that recurrent flooding and prolonged droughts, combined with an unsustainable shift in crop production from drought-tolerant millet to less resilient wheat and rice, led to harvest failures and food shortages during the cooler and drier climatic conditions of the late 9th and early 10th centuries CE. Intensifying raiding from competing polities and climatic extremes further affected grain supplies for the late Tang's northern military frontier and partly contributed to the sudden decline of the dynasty. Our results emphasize the importance of multicomponent environmental response models to understand historical transformations and provide new aspects of China's socio-political development during medieval times.

The European North-West shelf seas experienced a marine heatwave of unprecedented magnitude in June 2023. Quantifying the likelihood of reoccurrence of similar events is vital for mitigating impacts on marine ecosystems and human activities. Assessing the probability of such events is complicated by climate change-driven changes in the baseline conditions and the short length of the observational record with respect to modes of climate variability. Here, by employing a large ensemble of initialised climate model simulations, we show that the probability of June 2023-like events occurring is approximately 10% in any given year of the present-day climate. Moreover, there has been accelerating growth in the risk of occurrence over the last 30 years. The unprecedented nature of the record-breaking June 2023 event placed European marine heatwaves firmly in the public consciousness. However, the climate change trajectory means that whilst this event was unprecedented, such events should not be unexpected.

Permafrost thaw poses diverse risks to Arctic environments and livelihoods. Understanding the effects of permafrost thaw is vital for informed policymaking and adaptation efforts. Here, we present the consolidated findings of a risk analysis spanning four study regions: Longyearbyen (Svalbard, Norway), the Avannaata municipality (Greenland), the Beaufort Sea region and the Mackenzie River Delta (Canada) and the Bulunskiy District of the Sakha Republic (Russia). Local stakeholders' and scientists' perceptions shaped our understanding of the risks as dynamic, socionatural phenomena involving physical processes, key hazards, and societal consequences. Through an inter- and transdisciplinary risk analysis based on multidirectional knowledge exchanges and thematic network analysis, we identified five key hazards of permafrost thaw. These include infrastructure failure, disruption of mobility and supplies, decreased water quality, challenges for food security, and exposure to diseases and contaminants. The study's novelty resides in the comparative approach spanning different disciplines, environmental and societal contexts, and the transdisciplinary synthesis considering various risk perceptions.

The Last Ice Area-located to the north of Greenland and the northern Canadian Arctic Archipelago-is expected to persist as the central Arctic Ocean becomes seasonally ice-free within a few decades. Projections of the Last Ice Area, however, have come from relatively low resolution Global Climate Models that do not resolve sea ice export through the waterways of the Canadian Arctic Archipelago and Nares Strait. Here we revisit Last Ice Area projections using high-resolution numerical simulations from the Community Earth System Model, which resolves these narrow waterways. Under a high-end forcing scenario, the sea ice of the Last Ice Area thins and becomes more mobile, resulting in a large export southward. Under this potentially worst-case scenario, sea ice of the Last Ice Area could disappear a little more than one decade after the central Arctic Ocean has reached seasonally ice-free conditions. This loss would have profound impacts on ice-obligate species.

Biological carbon removal has been proposed as a 'win-win' for climate, sustainability and public opinion, but research on public perceptions is lacking explicit evidence on trade-offs between options. Here we explore perceptions using small group deliberation (n60) plus a nationally representative survey (n2027) in the UK's four jurisdictions. We find a strong preference for carbon removal to play a substantial role in meeting national climate targets, stemming from persistent scepticism about emissions reductions and behaviour change. However, such support was tempered with caution about whether certain biological techniques - biochar, peatland restoration, and perennial biomass crops - would be "worth it". In particular, concerns were raised about life-cycle emissions, as well as land competition with urgent housing needs, and scientific uncertainty around novel techniques such as biochar. While we find that responses to carbon removal tend to shift the burden of responsibility for climate action away from individuals, we also identify region-specific discourses, highlighting the importance of local context in shaping public views.

Stratospheric aerosol injection is a proposed method for offsetting greenhouse gas-induced warming by introducing scattering aerosols into the lower stratosphere to reflect sunlight. Here we explore a potentially more efficient alternative: weakening the Earth's greenhouse effect by deploying absorptive aerosols in the upper stratosphere (~10 hPa). These aerosols warm the carbon dioxide emission level-where outgoing longwave radiation is most sensitive to temperature-thereby enhancing top-of-atmosphere infrared emission without altering atmospheric carbon dioxide concentrations. Idealized climate model simulations indicate that this approach can reduce global temperatures an order of magnitude more efficiently per unit aerosol mass than conventional scattering-based interventions. Although based on simplified model experiments lacking interactive aerosol processes and operational constraints, our results identify a distinct physical mechanism for climate intervention, arguing for further research into the impacts-especially potential unintended side effects-of injecting absorptive aerosols into the upper stratosphere as an alternative solar radiation management strategy.

Bioarchaeology not only provides insights into human, animal, and environmental ecology, but also generates huge amounts of stable and radiogenic isotope data that are not well recognised by other disciplines. Here, we present potential avenues for the integration and interpretation of archaeological isotope data into environmental studies. We emphasise the large spatio-temporal scales on which isotope patterns can be observed, for example using isoscapes, the limitations and potential pitfalls that come with isotope data from archaeological research, and future cross-disciplinary collaborations between bioarchaeology and other palaeo-disciplines.

The snow and glaciers of the Peruvian Andes provide vital water supplies in a region facing water scarcity and substantial glacier change. However, there remains a lack of understanding of snow processes and quantification of the contribution of melt to runoff. Here we apply a distributed glacio-hydrological model over the Rio Santa basin to disentangle the role of the cryosphere in the Andean water cycle. Only at the highest elevations (>5000 m a.s.l.) is the snow cover continuous; at lower elevations, the snowpack is thin and ephemeral, with rapid cycles of snowfall and melt. Due to the large catchment area affected by ephemeral snow, its contribution to catchment inputs is substantial (23% and 38% in the wet and dry season, respectively). Ice melt is crucial in the mid-dry season (up to 44% of inputs). Our results improve estimates of water fluxes and call for further process-based modelling across the Andes.

Foliar exchange of methane and nitrous oxide is a significant yet poorly understood component of global greenhouse gas budgets. To address this knowledge gap, we investigated foliar methane and nitrous oxide fluxes in Salix bebbiana, under varying light conditions (0-2000 μmol·m^-2·s^-1), soil aeration, and nitrogen availability, manipulated via biochar incorporation and nitrogen additions. Using rapid spectroscopic gas analysers, we observed consistent net foliar methane oxidation and nitrous oxide emission across all light conditions, demonstrating saturating light response patterns. Maximum flux rates were significantly more sensitive to soil conditions than carbon dioxide or water vapour exchange. Analysis revealed foliar methane and nitrous oxide fluxes overwhelmingly regulated by internal leaf processes like xylem transport, with modulation by external light intensity. These predictable light-response patterns provide a basis for scaling leaf-level methane and nitrous oxide fluxes, enhancing accuracy in predicting biogenic greenhouse gas fluxes within ecosystem and biosphere models.

Large-scale removal of carbon dioxide from the atmosphere is required to meet net-zero targets. Enhanced rock weathering, in which crushed silicate minerals are spread on cropland soils, is a promising approach, but the logistics of its supply chain are poorly understood. Here, we use a numerical spatio-temporal allocation model that links potential rock extraction sites in the United Kingdom with croplands, modelling deployment pathways over the period 2025-2070. We find that expanding individual quarries (up to 20 times larger than the current average) and prioritising supply timing and location can increase carbon-removal efficiency by 20%, cut transport demand by 60% and reduce the number of operating quarries four-fold, while enabling up to 700 million tonnes of carbon dioxide removal by 2070. However, these large sites may face stronger local opposition and planning challenges, underscoring the critical role of policy in enabling feasible deployment.