One Earth最新文献

The western United States is home to most of the nation’s oil and gas production and, increasingly, wildfires. We examined historical threats of wildfires for oil and gas wells, the extent to which wildfires are projected to threaten wells as climate change progresses, and exposure of human populations to these wells. From 1984 to 2019, we found that, cumulatively, 102,882 wells were located in wildfire burn areas, and 348,853 people were exposed (resided within ≤ 1 km). During this period, we observed a 5-fold increase in the number of wells in wildfire burn areas and a doubling of the population within 1 km of these wells. These trends are projected to increase by late century, likely threatening human health. Approximately 2.9 million people reside within 1 km of wells in areas with high wildfire risk, and Black, Hispanic, and Native American people have disproportionately high exposure to wildfire-threatened wells.

Lake desiccation is a global problem associated with increased human water use and climate change. Like other drying lakes, Utah’s Great Salt Lake (GSL) is producing health-harming dust. We estimate social disparities in dust fine particulate matter (PM_2.5) exposures based on four policy-relevant water-level scenarios. Dust PM_2.5 exposures would increase as GSL levels drop (e.g., from 24.0 μg m⁻³ to 32.0 μg m⁻³). People of color and those with no high school diploma would experience disproportionately higher exposures (e.g., 28.4 μg m⁻³ for Pacific Islanders vs. 26.0 μg m⁻³ for Whites under very low lake levels). Racial/ethnic disparities would be reduced if GSL water levels rose. If the GSL vanished, racial/ethnic disparities between the highest and lowest exposed groups would be moderate (16.3%). If the GSL stabilized at healthy levels, those disparities would be smaller (7.9%). While all nearby residents face unhealthy dust exposures, findings reveal exposure disparities for socially disadvantaged groups.

Twenty-first century wildfires pose multifaceted challenges exacerbated by climate change and urbanization. Current mitigation measures often fall short, necessitating inclusive approaches that integrate Indigenous knowledge, historical ecology, and community-based strategies. Collaborative and integrated efforts are crucial to fostering sustainable fire management practices for resilient ecosystems and communities.

Forest fires are intensifying in a world bearing rapid anthropogenic climate change. Among the many factors affecting forest fire frequency and severity, such as hotter and drier conditions, there is also the increase in a certain kind of insect: bark beetles. Most bark beetles prefer dead tree wood as their diet, but some (e.g., the mountain pine beetle) have evolved to mass attack living trees. Previously, their larvae were kept in check by early winter freezes. However, in warmer winters, thanks to climate change, the larvae no longer freeze, plus more trees are drought and heat stressed, resulting in soaring reproduction of these beetles. The increasing volume of dry and combustible woody materials can help feed larger fires. Suze Woolf, an artist preoccupied with climate impacts on forests, observed their hieroglyphic “scribing” on bark and sapwood while hiking and turned those observations into a series of Bark Beetle Books. “Volume XIV: Ars datum est” is one that presents the trails of bark beetles—i.e., galleries where beetles deposit eggs—as a bar in a bar chart. The chart represents forest areas affected in British Columbia and Alberta from 1999 to 2007. These trails, to Suze, are undecipherable cryptograms that seem like a message we’re just not getting. This artist book, as Suze’s meditation on human impact, illustrates how bark beetles enthusiastically respond to the conditions we cooked: a warming world, a century of fire suppression, and a vast menu of even-aged agri-timbers over which we and the beetles now compete.

Evidence-based science communication and additional policy interventions are urgently needed to address widespread per- and poly-fluoroalkyl substance (PFAS) pollution. Messaging about PFASs should highlight exposure-reduction strategies and prioritize underserved communities. PFASs are not simply drinking-water pollutants; they are substances with myriad exposure pathways that require a systemic federal response.

As wildfires worsen across the globe, there is increased attention on the inequitable distribution of the risks to people. Pre-existing risks and vulnerabilities compound the risk to many populations. Those who bear the worst of these risks are usually underserved and ethnic/racial minority communities.

Marine euxinia can amplify phosphorous-limited marine productivity by recycling phosphorous from sediments, creating a feedback loop that increases marine oxygen consumption and ultimately leads to widespread oceanic anoxia. This phenomenon is potentially more dangerous when oxygen loss arises in coastal zones. Here, we present empirical evidence and show that this cascade was set off in the Cambrian Earth system. Carbon isotopes and Mo enrichments in well-dated sediment records from the Steptoean Positive Carbon Isotope Excursion (SPICE) event reveal a rapid decline over 130 ± 30 ka to persistently low Mo levels for 1.0 ± 0.2 Ma, followed by a slower recovery. Using dynamic models for the global biogeochemical cycles, we demonstrate that marine anoxia expanded globally through a self-cascading feedback mechanism. Importantly, we find that the benthic phosphorous flux likely scaled with sedimentation, and that chemocline shoaling into coastal areas likely triggered the SPICE event. We evaluate the risk of passing the tipping point for global-scale anoxia today.

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Around the world, fire regimes are shifting due to changing climate, land use and management, and human populations and infrastructure. While fire is a healthy and necessary process for many ecosystems, altered fire regimes are increasing risk to both people and wildlife in many regions. Reducing risk requires a holistic approach with investment from many stakeholders. In this Voices, we ask: what aspects of fire hazard, vulnerability, and exposure can be mitigated, and what collaborations does this require?

Social tipping points are promising levers for accelerating decarbonization progress. They describe how social, political, economic, or technological systems can move rapidly into a new state if positive feedback mechanisms are triggered. Analyzing the potential for social tipping requires the inherent complexity of social systems to be considered. Yet the growing social tipping literature is missing a practical framework that embeds conceptual and empirical aspects of complex feedback processes. In this perspective, we propose a dynamic systems approach that can contextualize conceptual social tipping mechanisms into practical interventions, and map the key feedback mechanisms underlying tipping dynamics across systems and scales. Our approach has three main components: a systems outlook involving interconnected feedback mechanisms; directed data collection for empirical evidence and monitoring tipping dynamics ; and global, integrated, descriptive modeling to project future dynamics and provide ex ante evidence for tipping interventions. We demonstrate how and why this approach should shape a broad agenda to strengthen the viability and effectiveness of social tipping research.