Communications Earth & Environment最新文献

Conspiracy theories on COVID-19 mRNA vaccines and solar geoengineering (chemtrails) tend to reinforce one another, thereby posing significant challenges to public policy and scientific norms and generating confusion by conflating disparate issues. This paper is based on ongoing ethnographic fieldwork conducted in the United States, Germany, Switzerland, and France since 2015 in these two areas of active conspiracy attention, involving observation of social media pages and blogs, active participation in gatherings, and semi-structured interviews. Here, I adopt a diplomatic perspective, highlighting the reciprocal suspicion between science policy and conspiratorial thinking in a competition between two sets of connections of scientific facts, values, politics, fears, and hopes. The present study suggests that the contamination of the scientific discourse by seemingly unrelated claims in conspiracy theories offers fruitful insights to science communication into how publics make sense of science and technology in the fierce debates surrounding immunization and climate policy.

Sedimentary volcanism, whereby material is brought to the surface by fluid overpressure, has been proposed to explain some of the periglacial landforms, including pitted cones, in the Northern Plains of Mars. However, in the absence of convincing mineralogical evidence, the origin for these deposits has never been conclusively determined. Here we conduct a remote sensing-based mineralogical survey to identify hydrated minerals within the Thumbprint Terrains and neighbouring Vastitas Borealis Formation. We detect several occurrences of hydrated silica along with sulfate salts in candidate mud volcano-like morphologies which likely formed during the Early Amazonian period, supporting the sedimentary volcanism origin. Buoyancy-driven analytical modelling suggests the hydrated silica and sulfate salts are sourced from reservoirs at depths of several 10 s and 100 s of metres, respectively below the Thumbprint Terrains and Vastitas Borealis Formation. The exposed sulfates may have been derived from ancient buried evaporite deposits suggesting, at least locally, a salt-rich aqueous origin for the Vastitas Borealis Formation, and would be consistent with the presence of a past northern ocean on Mars.

The Russian invasion of Ukraine has disrupted crop exports and global food security, overshadowing critical nutrient asymmetry and the associated environmental risks. Here we demonstrate that following nutrient shortages after independence in 1991, fertilizer use increased over 2000-2021, but has decreased sharply following the invasion in early 2022. Input-output balances of nitrogen (N), phosphorus (P) and potassium (K) for staple crops (wheat, maize and sunflower) highlight soil P and K mining since 1991, increasing N surpluses during 2000-2021 and large NPK deficits since the war began in 2022. Based on analysis of five scenarios for 2030, we show how an Integrated Nutrient Management Plan for Ukraine combining manure recycling, precision fertilization and legume expansion is urgently needed, and would maintain crop productivity, significantly reduce nutrient surpluses and improve nutrient use efficiencies up to 80-89%, substantially curtailing environmental pollution and soil degradation.

The eruption of Hunga volcano on 15 January 2022 was an exceptional event in the satellite era. Record-breaking heights of the volcanic plume were reported, a large amount of water was injected into the stratosphere and a broad spectrum of atmospheric waves were detected. Here, we use satellite measurements to show that a transient ring of small ice particles (~2 μm) formed around the plume. We hypothesize that the ice ring was generated by the passage of an atmospheric wave triggered by a pressure pulse at the surface corresponding to a violent explosion that occurred during the 15 January 2022 eruption sequence. The passage of the atmospheric wave produced a transient rarefaction in the upper troposphere-lower stratosphere, which in turn led to oscillations in ambient temperature. Due to the supersaturated state of the atmosphere with respect to ice, ice particles formed in the wake of the radially propagating atmospheric wave, allowing an exceptional opportunity to study ice particle growth via vapour deposition. This atmospheric phenomenon serves as an important natural experiment that reveals the time scale on which ice particles nucleate and grow given an abrupt perturbation in ambient temperature.

Reduced and polymerized phosphorus species may have been crucial for the origin and early evolution of life, as they are more reactive and soluble than phosphate. Thermal processes could have produced these phosphorus species; however, the underlying mechanism is poorly constrained, and geological evidence of polymerized species in the Precambrian is so far absent. Here, we investigated contact-metamorphic rocks from the ca. 3.22 Ga Moodies Group (South Africa), where mafic dikes intruded into shallow-marine sediments. We provide evidence of magmatic phosphite (up to 2.85 ppm) and metamorphic polyphosphate (up to 39.3 ppm). Additional laboratory experiments suggest that carbon can facilitate the thermal production of polyphosphates and reduced phosphorus species, including phosphide, from less reactive minerals such as apatite and vivianite. We conclude that magmatic and thermal-metamorphic rocks could have provided soluble and reactive phosphorus species crucial for the origin and early evolution of life.

Passenger aviation carbon footprint calculators often lack breadth, accuracy, transparency, and communication effectiveness, leading to underestimations of environmental impact and mistrust. This study addresses these gaps by developing a comprehensive methodology that broadens scope and improves accuracy. It incorporates nitrogen oxides, water vapour, contrail-induced cloudiness, upstream emissions from in-flight services, and life cycle emissions from aircraft and airports, offering a complete carbon footprint assessment. Accuracy is improved through detailed modelling of flight distance, fuel consumption, and emissions allocation adjusted for passenger class, luggage, and cargo. Historical adjustment factors refine pre-flight estimates by integrating real-world variations. The tool outputs a full emissions breakdown by source, offering unparalleled granularity and clarity. Validated against over 30,000 historical flights, the historical adjustment factor model achieves ~0.5% mean squared percentage error and shows current methods underestimate emissions. This study sets a standard for aviation carbon footprint calculators by enabling transparent, dynamic assessments for industry stakeholders.

Decarbonizing the energy sector requires renewable sources that are economic and responsive to demand. Intermittency and seasonal variability, therefore, limit the potential of wind and solar. Geothermal energy can potentially provide low-carbon renewable power that is dispatchable and responsive to demand. However, conventional geothermal methods require high permeability in high-temperature subsurface zones, which restricts their application. Here, we assess the global potential of the closed-loop geothermal system (CLGS), an emerging technology that does not require high permeability. Using thermodynamic, process, and technoeconomic modeling, we analyze the potential for CLGS in 12,000 candidate regions to estimate global viability. With the base case of water as the working fluid in a Rankine cycle, we estimate the global potential to be 9 TWe, equivalent to 70% of current electricity production. We assess using phase change working fluids to broaden applicability and improve efficiency, and evaluate the remaining technological barriers to closed-loop geothermal energy production.

Explosive volcanic eruptions are a major geo-hazard. Given the energetic nature of eruptive processes, direct observation is limited, making the study of deposits and pyroclast textures essential for understanding eruption dynamics. Experimental constraints therefore provide a vital contribution to improving hazard assessment. We performed tumbling experiments using pumice lapilli from the Laacher See eruption (Eifel, Germany) to investigate ash generation and pyroclast shape evolution. Before and after each experimental step, samples were sieved, and the volume and four morphological parameters (axial ratio, convexity, form factor, solidity) of 100 clasts were measured. Most shape change happened before the first 15 min (first experimental step) and produced up to 48 wt.% ash. We frame our analysis in terms of effective relaxation timescales, whereby pyroclasts display a decelerating rate of shape change towards a time-invariant morphology. This quantification of the susceptibility of porous pyroclasts to changes enhances our understanding of transport processes from clast generation to sedimentation.

Fossils preserving soft tissues and lightly biomineralized structures are essential for the reconstruction of past ecosystems and their evolution. Understanding fossilization processes, including decay and mineralisation, is crucial for accurately interpreting ancient morphologies. Here we investigate the decay of marine and freshwater shrimps deposited on the surface of three different clay beds. In experimental set ups containing kaolinite, cryogenic scanning electron microscopy shows a black film comprised of newly formed anhedral and cryptocrystalline aluminosilicates on marine shrimp cuticles, which stabilise the overall morphology. This is the first experimental evidence for the replication of arthropod lightly biomineralized structures in aluminosilicates shortly after death, while carcasses are not buried by sediments. The preservation of morphology through aluminosilicates could result in carcasses persisting on the seafloor for weeks without losing much external anatomical information. In this context, instantaneous burial capturing animals alive may not be a prerequisite for exceptional preservation as usually thought.

Agriculture and food systems are major sources of plastic pollution but they are also vulnerable to their diverse lifecycle impacts. However, this problem is not well-recognized in global policy and scientific discourse, agendas, and monitoring of food systems. The United Nations-led Global Plastics Treaty, which has been under negotiation since 2022, is a critical opportunity to address pollution across the entire plastics lifecycle for more sustainable and resilient food systems. Here, we offer aspirational indicators for future monitoring of food systems' plastics related to (1) plastic polymers and chemicals, (2) land use, (3) trade and waste, and (4) environmental and human health. We call for interdisciplinary research collaborations to continue improving and harmonising the evidence base necessary to track and trace plastics and plastic chemicals in food systems. We also highlight the need for collaboration across disciplines and sectors to tackle this urgent challenge for biodiversity, climate change, food security and nutrition, health and human rights at a whole systems level.