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1.
iScience ; 27(6): 110107, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38947528

RESUMO

The Ediacaran of Newfoundland preserves some of the oldest complex macroscopic communities, several of which are dominated by the fractal-like rangeomorph genus Fractofusus. Here we use computational fluid dynamics and a detailed reconstruction of Fractofusus misrai to document for the first time hydrodynamic phenomena associated with this sediment-reclining organism and its rangeomorph elements that are relevant to interpreting feeding strategies, explain the recently documented rheotropic growth oblique to currents, and provide insights into their impact on the Ediacaran seafloor. Obliquely oriented Fractofusus are common, likely representing a compromise between maximized aspect ratio and minimization of drag. Flow patterns on the upper surface of Fractofusus are consistent with the collection of dissolved and finely particulate nutrients, as well as gas exchange. Fractofusus produce a wake downstream, demonstrating that reclining rangeomorphs had potential to modify sedimentation patterns on the ancient seafloor by potentially allowing deposition of fine-grained sediment.

2.
iScience ; 27(7): 110066, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38989469

RESUMO

In light of the increasing vulnerability to drought occurrences and the heightened impact of drought-related disasters on numerous communities, it is imperative for drought-sensitive sectors to adopt proactive measures. This involves the implementation of early warning systems to effectively mitigate potential risks. Guided by Toulmin's model of argumentation, this research proposes a framework of eight interconnected modules introducing Fourth Industrial Revolution technologies to enhance drought early warning capabilities. The framework emphasizes the Internet of Things, drones, big data analytics, and deep learning for real-time monitoring and accurate drought forecasts. Another key component is the role of natural language processing in analyzing data from unstructured sources, such as social media, and reviews, essential for improving alerts, dissemination, and interoperability. While the framework optimizes resource use in agriculture, water, and the environment, overcoming impending limitations is crucial; hence, practical implementation and amendment of policies are necessary.

3.
iScience ; 27(7): 110236, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39015147

RESUMO

The reduction in sea ice cover with Arctic warming facilitates shipping through remarkably shorter shipping routes. Automatic identification system (AIS) is a powerful data source to monitor Arctic Ocean shipping. Based on the AIS data from an online platform, we quantified the spatial distribution of shipping through this area, its intensity, and the seasonal variation. Shipping was heterogeneously distributed with power-law exponents that depended on the vessel category. We contextualized the estimated exponents with the analytical distribution of a transit model in one and two dimensions. Fishing vessels had the largest spatial spread, while narrower shipping routes associated with cargo and tanker vessels had a width correlated with the sea ice area. The time evolution of these routes showed extended periods of shipping activity through the year. We used AIS data to quantify recent Arctic shipping, which brings an opportunity for shorter routes, but likely impacting the Arctic ecosystem.

4.
STAR Protoc ; 5(2): 103124, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38870017

RESUMO

Global warming will change the photosynthesis and transpiration of plants greatly and ultimately affect water use efficiency (WUE). Here, we present a protocol to investigate the response of maize WUE to the coupling effect of CO2 and temperature at ear stage using a specialized designed gradient. We describe steps for plant culture, parameter measurements, model fitting, and statistical analysis. This protocol holds potential for studying the response of WUE and CO2 adaptation across various plant species. For complete details on the use and execution of this protocol, please refer to Sun et al.1.


Assuntos
Dióxido de Carbono , Fotossíntese , Temperatura , Zea mays , Zea mays/fisiologia , Dióxido de Carbono/metabolismo , Fotossíntese/fisiologia , Água/metabolismo , Transpiração Vegetal/fisiologia
5.
iScience ; 27(6): 109957, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38827410

RESUMO

The subsurface is pivotal in the energy transition, for the sequestration of CO2 and energy storage. It is crucial to understand to what extent geological faults may form leakage pathways that threaten the containment integrity of these projects. Fault flow behavior has been studied in the context of hydrocarbon development, supported by observations from wells drilled through faults, but such observations are rare in geoenergy projects. Focusing on mechanical behavior as early indicator of potential leakage risks, a probabilistic Coulomb Failure Stress workflow is developed and demonstrated using data from the Decatur CO2 sequestration project to rank faults based on their containment risk. The analysis emphasizes the importance of fault throw relative to reservoir thickness and pore pressure change in assessing reactivation risks. Integrating this mechanical assessment with geological and dynamic fault analyses contributes to derisking fault containment for geoenergy applications, providing valuable insights for the successful development of subsurface storage projects.

6.
iScience ; 27(6): 109812, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38784017

RESUMO

While artificial intelligence (AI) offers promising solutions to address climate change impacts, it also raises many application limitations and challenges. A risk governance perspective is used to analyze the role of AI in supporting decision-making for climate adaptation, spanning risk assessment, policy analysis, and implementation. This comprehensive review combines expert insights and systematic literature review. The study's findings indicate a large emphasis on applying AI to climate "risk assessments," particularly regarding hazard and exposure assessment, but a lack of innovative approaches and tools to evaluate resilience and vulnerability as well as prioritization and implementation process, all of which involve subjective, qualitative, and context-specific elements. Additionally, the study points out challenges such as difficulty of simulating complex long-term changes, and evolving policies and human behavior, reliance on data quality and computational resources, and the need for improved interpretability of results as areas requiring further development.

7.
iScience ; 27(5): 109598, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38799075

RESUMO

The Longxiang tracksite (lower Upper Cretaceous, Shanghang Basin) includes twelve didactyl deinonychosaur tracks that fall into two morphologies, differentiated by both size and form. The smaller tracks (∼11 cm long) are referable to the ichnogenus Velociraptorichnus. The larger tracks (∼36 cm long) establish the ichnotaxon Fujianipus yingliangi. Based on the size of the tracks, F. yingliangi has an estimated hip height of over 1.8 m, a size comparable to that of the largest known deinonychosaurs, i.e., Austroraptor and Utahraptor. The reduced form of digit IV, relative to digit III, indicates that F. yingliangi is a probable troodontid. Gigantism evidently evolved independently at least four times within the Deinonychosauria and within at least three major lineages: the Eudromaeosauria, Unenlagiidae, and Troodontidae. In the mid-Cretaceous of Asia, the evolution of F. yingliangi overlapped with that of early large-bodied tyrannosauroids and with previously established large allosaurids (although the latter may have been in decline).

8.
iScience ; 27(6): 109905, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38799561

RESUMO

Tropical cyclone (TC) intensity change forecasting remains challenging due to the lack of understanding of the interactions between TC changes and environmental parameters, and the high uncertainties resulting from climate change. This study proposed hybrid convolutional neural networks (hybrid-CNN), which effectively combined satellite-based spatial characteristics and numerical prediction model outputs, to forecast TC intensity with lead times of 24, 48, and 72 h. The models were validated against best track data by TC category and phase and compared with the Korea Meteorological Administrator (KMA)-based TC forecasts. The hybrid-CNN-based forecasts outperformed KMA-based forecasts, exhibiting up to 22%, 110%, and 7% improvement in skill scores for the 24-, 48-, and 72-h forecasts, respectively. For rapid intensification cases, the models exhibited improvements of 62%, 87%, and 50% over KMA-based forecasts for the three lead times. Moreover, explainable deep learning demonstrated hybrid-CNN's potential in predicting TC intensity and contributing to the TC forecasting field.

9.
NPJ Nat Hazards ; 1(1): 7, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38726463

RESUMO

A new time-dependent probabilistic tsunami risk model is developed to facilitate the long-term risk management strategies for coastal communities. The model incorporates the time-dependency of earthquake occurrence and considers numerous heterogeneous slip distributions via a stochastic source modeling approach. Tidal level effects are examined by considering different baseline sea levels. The model is applied to Tofino, British Columbia, Canada within the Cascadia subduction zone. High-resolution topography and high-quality exposure data are utilized to accurately evaluate tsunami damage and economic loss to buildings. The results are tsunami loss curves accounting for different elapsed times since the last major event. The evolutionary aspects of Tofino's time-dependent tsunami risk profiles show that the current tsunami risk is lower than the tsunami risk based on the conventional time-independent Poisson occurrence model. In contrast, the future tsunami risk in 2100 will exceed the time-independent tsunami risk estimate.

10.
Nature ; 629(8012): 538-539, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38719959
11.
iScience ; 27(5): 109613, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38638563

RESUMO

Evidence of hot and cold igneous processes has been reported in small satellites and dwarf planets of the Solar System. Olivine and pyroxenes were detected in the spectral bands of both small satellites and dwarf planets. The aqueously altered form of olivine and serpentine has been detected in the spectrums of Ceres and Miranda hinting at possible hydrothermal processes in their interiors. Once more, the ubiquitous distribution of 26Al in the planetary nebula, then evolving in the protoplanetary disk, contributed to the primordial widespread heating. Volcanism, or cryovolcanism, then developed only in those bodies where long-lived radiogenic elements, and/or tidal processes, were available.

13.
Proc Natl Acad Sci U S A ; 121(19): e2209196121, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38640256

RESUMO

Increasing the speed of scientific progress is urgently needed to address the many challenges associated with the biosphere in the Anthropocene. Consequently, the critical question becomes: How can science most rapidly progress to address large, complex global problems? We suggest that the lag in the development of a more predictive science of the biosphere is not only because the biosphere is so much more complex, or because we do not have enough data, or are not doing enough experiments, but, in large part, because of unresolved tension between the three dominant scientific cultures that pervade the research community. We introduce and explain the concept of the three scientific cultures and present a novel analysis of their characteristics, supported by examples and a formal mathematical definition/representation of what this means and implies. The three cultures operate, to varying degrees, across all of science. However, within the biosciences, and in contrast to some of the other sciences, they remain relatively more separated, and their lack of integration has hindered their potential power and insight. Our solution to accelerating a broader, predictive science of the biosphere is to enhance integration of scientific cultures. The process of integration-Scientific Transculturalism-recognizes that the push for interdisciplinary research, in general, is just not enough. Unless these cultures of science are formally appreciated and their thinking iteratively integrated into scientific discovery and advancement, there will continue to be numerous significant challenges that will increasingly limit forecasting and prediction efforts.


Assuntos
Previsões , Matemática
14.
iScience ; 27(4): 109446, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38550999

RESUMO

The Hunga Tonga-Hunga Ha'apai (HTHH) volcano eruption received worldwide attention due to its magnitude and potential effects on environment and climate. However, the operational sulfur dioxide (SO2) products mis-estimated SO2 emissions under volcanic conditions due to large uncertainties in the assumptions of SO2 plume altitude. That might have occurred in previous volcanic eruptions and misled understanding of the evolution of sulfate aerosols in the atmosphere and their impact on global climate. Here, we simultaneously retrieved the volcanic SO2 and its plume altitude from the Troposphere Monitoring Instrument (TROPOMI) and the Environment Monitoring Instrument-2 (EMI-2), exploring the SO2 burden, distribution, and evolution from January 14 to 17. We captured multiple eruptions with the second eruption emitting far more SO2 than the first. Total emissions exceeded 900 kt, significantly higher than those from operational products. Our inferred emission fluxes and injection heights offer valuable references for climate modeling and submarine volcano studies.

15.
iScience ; 27(4): 109412, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38510121

RESUMO

Addressing the equitable distribution of global carbon emission rights is critical for sustainable development. Our research develops a detailed framework for a Global Carbon Reduction Alliance based on regional cooperation strategies, identifying key modes of intracontinental proximity and intercontinental distance collaboration. It emphasizes alliances formed among high carbon emission right countries and leadership-driven models propelling low carbon emission right countries, offering insights for optimizing emission reduction efforts. The analysis highlights the strategic role of developing nations in Africa and Asia, as well as developed regions in Europe and North America, advocating for the adoption of clean energy, enhancement of forest economic value, acceleration of urbanization, and an increased contribution of the service sector to the economy as essential pathways to achieving net-zero emissions. Our approach advocates for a comprehensive model of global carbon reduction cooperation, aiming at the equitable distribution of carbon emission rights and supporting the sustainable development goals.

16.
iScience ; 27(4): 109420, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38510133

RESUMO

The need to enhance nutrient production from tropical ecosystems to feed the poor could potentially create a new framework for fisheries science and management. Early recommendations have included targeting small fishes and increasing the species richness of fish catches, which could represent a departure from more traditional approaches such as biomass-based management. To test these recommendations, we compared the outcomes of biomass-based management with hypothesized factors influencing nutrient density in nearshore artisanal fish catches in the Western Indian Ocean. We found that enhancing nutrient production depends primarily on achieving biomass-based targets. Catches dominated by low- and mid-trophic level species with smaller body sizes and faster turnover were associated with modest increases in nutrient densities, but the variability in nutrient density was small relative to human nutritional requirements. Therefore, tropical fishery management should focus on restoring biomass to achieve maximum yields and sustainability, particularly for herbivorous fishes.

17.
Nature ; 627(8002): 236, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38438542
18.
iScience ; 27(3): 109110, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38433922

RESUMO

Increasing urbanization exacerbates surface energy balance perturbations and the health risks of climate warming; however, it has not been determined whether urban-induced warming and attributions vary from local, regional, to global scale. Here, the local surface urban heat island (SUHI) is evidenced to manifest with an annual daily mean intensity of 0.99°C-1.10°C during 2003-2018 using satellite observations over 536 cities worldwide. Spatiotemporal patterns and mechanisms of SUHI tightly link with climate-vegetation conditions, with regional warming effect reaching up to 0.015°C-0.138°C (annual average) due to surface energy alterations. Globally, the SUHI footprint of 1,860 cities approximates to 1% of the terrestrial lands, about 1.8-2.9 times far beyond the urban impervious areas, suggesting the enlargements of the imprint of urban warming from local to global scales. With continuous development of urbanization, the implications for SUHI-added warming and scaling effects are considerably important on accelerating global warming.

20.
iScience ; 27(3): 109079, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38361631

RESUMO

China as a major coal-consuming economy faces the challenge of balancing economic development and carbon neutrality goal. This paper incorporates both efficiency-based and equity-based carbon neutrality policies into a numerical model to quantitatively assess how coal reduction under various carbon-neutral policies affects energy mix, economic growth, and industrial structures by 2060. Results show the nationwide coal intensity will ultimately plunge by over 95% from 2017 to 2060, mainly attributed to the coal-phasing-out in most industries. National Gross Domestic Product losses reaches 4,951 billion USD in efficiency-based scenarios by 2060, and the economic losses are even more severe in less developed provinces, especially provinces in Northern China. Although the equity-based policy can reduce the economic burden for the Northern China, the equity-based policy is accompanied by a significant regional shift in coal across the country: eastern coal-intense industries will be relocated northward, leading to increases in embodied coal consumption.

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