One Earth最新文献

Carbon dioxide removal (CDR) technologies are essential to address climate change and serve to compensate for legacy and hard-to-abate greenhouse gas emissions. Although near-term emissions reductions should be the priority, development and deployment of CDR must proceed now to ensure that relevant technologies are ready at scale in the future. Despite a rapid growth in CDR purchases, no single standardized methodology for evaluating project-level net CO₂ removal exists. Life cycle assessment (LCA) frequently produces net-negative emissions footprints, but only a small subset of those systems achieves a net flux of CO₂ out of the atmosphere. In contrast to LCA, CDR accounting uses expansive system boundaries and excludes avoidance credits to distinguish between systems that achieve net removal from those that only contribute to emissions mitigation. This primer discusses a framework and set of metrics for CDR accounting.

There is an increasing urgency to implement large-scale ecosystem restoration to mitigate the biodiversity and climate crises. These efforts must be scaled up to counteract the widespread degradation of the world’s forests, although restoration costs can often limit their application. Thus, there is a pressing need to identify cost-effective approaches that catalyze landscape-scale ecological recovery. Here, we highlight seven assisted restoration innovations with demonstrated local-scale results that, once upscaled, hold promise to rapidly regenerate forests. We comprehensively assessed how each approach facilitated forest, woodland, and/or mangrove recovery across 143 studies. Our results reveal techniques with a marked ability to catalyze vegetation recovery compared to “business-as-usual” approaches. However, the context-dependent cost-benefit ratio and feasibility of applying particular approaches requires careful consideration. Our assessment emphasizes that we already have many of the tools necessary to drive the terrestrial restoration movement forward. It is time to implement and assess their efficacy at scale.

Glaciers are crucial water resources in the Third Pole (the Tibetan Plateau and its surroundings) and are shrinking in response to climate change. Glacier albedo is an expression of glacier interactions with climate and dust/black carbon, and albedo reduction enhances glacier mass loss, but its changes and potential drivers remain poorly quantified. We leverage satellite observations to explore the variability of glacier albedo and understand its sensitivity to potential drivers and its future evolution. We find that glacier albedo has declined during 2001–2020, but high interannual variability is also an important signal. These variations are highly sensitive to air temperature and snow conditions and to nearby dust/black carbon emission sources. Future changes to these drivers will lead to further decreases of 2.9%–12.5% in glacier albedo by 2100 under different warming scenarios. These findings highlight the importance of albedo in glacier future evolution and the urgency of action to mitigate climate warming.

Defining an Anthropocene epoch from the mid-1900s allows representing human environmental impacts’ triphasic nature within the International Geological Timescale. Such an epoch captures humanity’s current planetary importance, with the Holocene and Late Pleistocene representing earlier phases of intensifying impacts. This formal framework empowers science and action toward planetary stewardship.

Nitrogen oxides (NO_x) and ammonia (NH₃) contribute substantially to current global fine particulate matter (PM_2.5) pollution. Their future role remains unclear and is complicated by interactions with background emissions. Here, we show that under climate mitigation scenarios, by 2050, a hypothetical phaseout of anthropogenic NH₃ emissions would reduce PM_2.5 by 20%–60% locally and be more effective than phasing out NO_x. Reducing NH₃ by 25%, instead, would be less effective than 25% NO_x reduction for many regions. Future reductions of NO_x and sulfuric dioxides from clean energy transitions would shift the nonlinear chemical regime of secondary inorganic aerosol formation toward NH₃ saturation. The later NH₃ controls are installed, the deeper the required reductions will be to be effective, although for many regions such levels are still within technical feasibility, while NO_x controls will always remain effective. Nitrogen reductions remain useful for achieving the World Health Organization guideline target for PM_2.5, and NH₃ controls need to happen sooner rather than later.

The intertwined crises of biodiversity loss and climate change pose a significant sustainability challenge, threatening ecosystems and human well-being globally. Yet, the nuanced interplay between these challenges is often understated in policy dialogs. Global biodiversity targets, including 30% protection of the Earth’s surface by 2030, may fall short without robust climate change mitigation. Here, we illustrate that conservation through protected areas can effectively preserve forest productivity and carbon capture, which depend on tree diversity. However, failing to mitigate climate change diminishes the effectiveness of these areas, especially in warmer biomes. Even with optimal protected area selection, preserving tree diversity-dependent productivity could be compromised without significant climate change mitigation. Our findings emphasize the need to integrate climate change mitigation into biodiversity conservation policies to ensure the success of the 30 × 30 targets and sustain the ecosystem benefits biodiversity provides to society.

Soil phosphorus (P) directly impacts major sustainability outcomes, namely crop yields, water quality, and carbon sequestration. Optimally managing P to improve sustainability outcomes requires a mechanistic understanding of P availability and transfer, alongside high-resolution spatial data. However, it is unclear if current measurement techniques, models, and maps meet the demands for science-informed management. Here, we review recent advances in measuring P fluxes, quantifying P availability, and mapping soil P resources and discuss implications for sustainability outcomes. We find that the understanding of soil P availability has significantly improved but that agronomical applications and climate models are still largely based on outdated concepts. Also, we find that spatial data on soil P resources are highly uncertain, limiting the usefulness of current P maps. We highlight steps to improve existing tools and emphasize that these improvements need to go hand in hand with policy and technological development to successfully address P-related sustainable development goals.

Summers have always been hot, but we are experiencing exceedingly intensive heat across the world. Global temperature records break headlines more frequently thanks to anthropogenic climate change. In response to the deadly heatwave of 2020—which engulfed Europe with record-breaking temperatures and caused tens of thousands of deaths—artist and climate activist Diane Burko created Summer Heat. This 7 × 13 ft painting illustrates the causes and effects of climate change clashing into each other by displaying the Earth’s continents underneath splashes of red and blue, which reflect on the EU record-breaking heat and melting glaciers, dripping across the canvas, juxtaposed with the iconic Keeling curve that presents the accumulation of CO₂ in the Earth’s atmosphere based on continuous measurements taken at the Mauna Loa Observatory since 1958. This artwork was further used in a study and showed its positive influence on bridging political divisions in climate change.

International research in Global South cities is urgently needed to address unprecedented heat, enervating humidity, and daunting social inequality projected to impact >3 billion urbanites in Asia and Africa. Yet, researchers are ill-equipped to navigate cultural and physiological challenges inherent in this work, for which we develop cross-cultural protocols.