地球科学最新文献

{"title":"Emergence of anthropogenic precipitation changes in a future warmer climate","authors":"Shoji Kusunoki, Ryo Mizuta, Masahiro Hosaka","doi":"10.1038/s41612-025-01128-3","DOIUrl":"https://doi.org/10.1038/s41612-025-01128-3","url":null,"abstract":"<p>The ‘emergence year’ <i>Ye</i> is defined as the start of a future period during which precipitation consistently exceeds the maximum value of the past historical period. Emergence years of future anthropogenic changes in annual average precipitation (<i>Pav</i>) and annual maximum 1-day precipitation (<i>P1d</i>) were projected using high-resolution global atmospheric models with 20-km and 60-km grid-size for the period 1950-2099. A total of 10,000 randomized time series representing the time evolution of decadal natural variability enabled us to directly evaluate estimated frequency distributions (EDFs) on a grid point basis. <i>Ye</i> for both <i>Pav</i> and <i>P1d</i> generally occur earlier at high latitudes than they are elsewhere, and <i>Ye</i>(<i>P1d</i>) is generally later than <i>Ye</i>(<i>Pav</i>). <i>Ye</i>(<i>P1d</i>) covers a larger area than <i>Ye</i>(<i>Pav</i>) does and <i>Ye</i>(<i>P1d</i>) may occur earlier in the tropics and mid-latitudes than <i>Ye</i>(<i>Pav</i>). <i>Ye</i> occurs earlier in scenarios with higher anthropogenic emissions than in scenarios with lower emissions.</p>","PeriodicalId":19438,"journal":{"name":"npj Climate and Atmospheric Science","volume":"148 1","pages":""},"PeriodicalIF":9.0,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144547389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prioritizing Urban Emission Reductions to Mitigate Pollution and Health Effects of Ozone and Nitrogen Dioxide in China","authors":"Zhaolei Zhang,&nbsp;Wenxuan Yu,&nbsp;Shuai Wang,&nbsp;Xinyue Li,&nbsp;Xia Meng,&nbsp;Peng Wang,&nbsp;Hongliang Zhang","doi":"10.1029/2024JD042831","DOIUrl":"https://doi.org/10.1029/2024JD042831","url":null,"abstract":"<p>Despite significant reductions in fine particulate matter (PM_2.5) concentrations in China due to air pollution control measures, ozone (O₃) pollution has worsened in recent years, with pronounced regional disparities in long-term exposure to O₃ and NO₂. Assessing these disparities in exposure to gaseous pollutants and the resulting unequal health risks between urban and rural regions has become increasingly essential. The contributions of various anthropogenic emissions to O₃ and NO₂ were quantified using a source-oriented version of the Community Multiscale Air Quality (CMAQ) model, combined with population and GDP data sets. From 2010 to 2019, NOx and VOC emissions from non-urban areas decreased by 14% and 25%, respectively, whereas urban anthropogenic activities caused a 10% increase in NOx emissions and a 22% rise in VOC emissions. The simulations indicated that background levels constituted the majority of maximum daily 8-hr average O₃ (MDA8 O₃), contributing 83% in 2010 and 75% in 2019. Non-urban anthropogenic activities were the primary sources of NO₂, accounting for 64% in 2010 and 57% in 2019. The proportion of O₃ and NO₂ from urban anthropogenic emissions in the total concentration continuously increased between 2010 and 2019. Although overall O₃-related premature mortality increased by 51% and NO₂-related premature mortality decreased by 3% during this period, the number of premature mortalities related to O₃ and NO₂ from urban anthropogenic activities rose by 133% and 15% respectively. We underscore the critical need to prioritize the reduction of urban anthropogenic emissions to effectively mitigate O₃ and NO₂ pollution in China.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"130 13","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144550948","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring the Magnetotail From Low Altitudes: Evolution of Energetic Electron Flux During the Substorm Growth Phase","authors":"Weiqin Sun,&nbsp;Xiao-Jia Zhang,&nbsp;Anton V. Artemyev,&nbsp;Rumi Nakamura,&nbsp;Vassilis Angelopoulos","doi":"10.1029/2025JA033882","DOIUrl":"https://doi.org/10.1029/2025JA033882","url":null,"abstract":"<p>The magnetospheric substorm, which plays a crucial role in flux and energy transport across Earth's magnetosphere, features the formation of a thin, elongated current sheet in the magnetotail during its growth phase. This phase is characterized by a decrease in the equatorial magnetic field <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>B</mi>\u0000 <mi>z</mi>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${B}_{z}$</annotation>\u0000 </semantics></math> and the stretching of magnetic field lines. Observing these large-scale magnetic field reconfigurations is challenging with single-point satellite measurements, which provide only spatially localized snapshots of system dynamics. Conversely, low-altitude spacecraft measurements of energetic electron fluxes, such as those from Electron Losses and Fields Investigation (ELFIN), offer a unique opportunity to remotely sense the equatorial magnetic field in the magnetotail during substorms by measuring the latitudinal variations of energetic electron isotropic fluxes. Because of strong scattering caused by the curvature of magnetic field lines, energetic electrons in the magnetotail are mostly isotropic. Consequently, variations in their fluxes at low altitudes are expected to reflect the reconfiguration of the magnetotail magnetic field. To better understand the connection between electron flux variation at low altitudes and magnetic field reconfiguration during substorms, we compared low-altitude ELFIN observations with simulations from the Rice Convection Model (RCM). The RCM, which assumes fully isotropic electron distributions, provides a robust framework for describing energetic electron dynamics in the plasma sheet and determining the self-consistent magnetic field configuration during substorms. The comparison of ELFIN observations and RCM simulations confirms our interpretation of electron flux dynamics at low altitudes during the substorm growth phase and validates the use of such observations to infer magnetotail dynamics during substorms.</p>","PeriodicalId":15894,"journal":{"name":"Journal of Geophysical Research: Space Physics","volume":"130 7","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144536852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seismic Velocities of Subducted Serpentinites Through the Lizardite-Antigorite Transition","authors":"He-Ming Wang,&nbsp;Mai-Linh Doan,&nbsp;Anne-Line Auzende,&nbsp;Stéphane Schwartz,&nbsp;Samuel Chapman,&nbsp;Jérôme Fortin,&nbsp;Xiao-Ming Tang","doi":"10.1029/2025GL116304","DOIUrl":"https://doi.org/10.1029/2025GL116304","url":null,"abstract":"<p>The mineralogical transition (lizardite to antigorite) occurring in serpentinites dragged down in subduction zones depends on the metamorphic pressure and temperature conditions. The seismic Vp/Vs ratio is useful for distinguishing serpentinites from other mantle rocks. To understand the effects of the metamorphic conditions and the associated microstructural evolution on the serpentinite velocity, we collected seven natural serpentinite rocks with different metamorphic imprints in the Western Alps, from blueschists to eclogite facies conditions. We measured the ultrasonic velocity of the samples at confining pressures up to 70 MPa. The measured seismic Vp and Vs increase with the increasing metamorphic conditions, while the Vp/Vs ratio decreases. The petrological results are used to explain the velocity anisotropy and the weak pressure-dependency of velocity. The new Vp/Vs transition trend provides new constraints for tracking the lizardite/antigorite transition with increasing metamorphic condition from field seismic data and thus studying geodynamic evolution in the subduction environment.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 13","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025GL116304","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144537137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of Airborne Radio Occultation Observations on Short Term Precipitation Forecasts of an Atmospheric River","authors":"Phuong-Nghi Do,&nbsp;Jennifer S. Haase,&nbsp;Ivette Hernández Baños,&nbsp;Pawel Hordyniec,&nbsp;Bing Cao","doi":"10.1029/2025GL115639","DOIUrl":"https://doi.org/10.1029/2025GL115639","url":null,"abstract":"<p>Atmospheric River Reconnaissance (AR Recon) collects targeted observations during major winter weather events associated with heavy precipitation and flooding on the US West Coast. Ten WC-130J weather reconnaissance aircraft equipped with Global Navigation Satellite System airborne radio occultation (ARO) technology provide additional data on the broader AR environment, specifically as the AR approaches the coastline. This study evaluates the impact of assimilating ARO bending angle observations using the Model for Prediction Across Scales—Atmosphere—Joint Effort for Data assimilation Integration (MPAS-JEDI). Experiments use the Local Ensemble Transform Kalman Filter and Three-Dimensional Ensemble-Variational algorithms. The control experiment assimilates only global conventional data, while the other experiments incorporate additional ARO observations. The results show that ARO assimilation corrects moisture, temperature, and wind fields, and reduces the error in the integrated vapor transport forecast at landfall. The changes mitigate overestimated precipitation in mountainous regions of Washington and Idaho.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 13","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025GL115639","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144537141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fixation and liberation of smectite interlayer cations under dry and wet conditions","authors":"Artur Kuligiewicz ,&nbsp;Reiner Dohrmann ,&nbsp;Stephan Kaufhold ,&nbsp;Adam Zięba ,&nbsp;Arkadiusz Derkowski","doi":"10.1016/j.clay.2025.107914","DOIUrl":"10.1016/j.clay.2025.107914","url":null,"abstract":"<div><div>The aim of the present study was to examine changes in the layer charge (LC) of smectite heated for an extended period of time under two contrasting conditions: wet (hydrothermal experiments) and dry (oven heating). Understanding smectite's behavior at elevated temperatures is crucial, e.g., in the case of high-level radioactive waste storage facilities, where bentonites (smectite-rich rocks) are planned to be used as one of the barriers. A set of two montmorillonites and one beidellite in four cationic forms, Mg²⁺, Ca²⁺, Fe²⁺, and K⁺, was heated at 100 or 200 °C for up to 157 days. In addition, LC regeneration tests involving cation exchange and hydrothermal treatment of oven-dried samples were performed. LC was measured using the spectroscopic OD method, whereas X-ray diffraction was used to verify the changes detected by the OD method. In the dry-heating experiments, most samples showed stable LC values up to 146 days of heating, except the LC decrease for Fe²⁺ and Mg²⁺-exchanged montmorillonite, which was interpreted as resulting from the formation of inner-sphere complexes and/or penetration of these cations into the octahedral sheet. The LC values of samples after hydrothermal experiments were more variable, possibly due to the cation exchange, and dissolution and reprecipitation processes. In the case of Fe²⁺-exchanged samples reacted hydrothermally at 200 °C, kaolinite was formed at the expanse of smectite, and collapsed interlayers formed in K⁺-exchanged samples reacted under the same conditions. Cation exchange and hydrothermal treatment were not always successful in restoring the initial LC of samples, however, hydrothermal rehydration reaction was efficient in the case of samples dried at 100 °C. The paper presents the mechanism of interlayer cations fixation and liberation, which change the properties of smectite-rich bentonite barriers for nuclear waste disposal under partially dry vs. water-saturated conditions. Reversible after drying at 100 °C and irreversible after 200 °C cation fixation match common temperature limits of bentonite exposure to radioactively-produced heat.</div></div>","PeriodicalId":245,"journal":{"name":"Applied Clay Science","volume":"276 ","pages":"Article 107914"},"PeriodicalIF":5.3,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144534182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative analysis of sea salt species in snow samples from Svalbard using ICP-QMS and IC techniques","authors":"Azzurra Spagnesi ,&nbsp;Elena Barbaro ,&nbsp;Warren Raymond Lee Cairns ,&nbsp;Matteo Feltracco ,&nbsp;Federico Scoto ,&nbsp;Andrea Gambaro ,&nbsp;Carlo Barbante ,&nbsp;Andrea Spolaor","doi":"10.1016/j.apgeochem.2025.106492","DOIUrl":"10.1016/j.apgeochem.2025.106492","url":null,"abstract":"<div><div>Inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) and ion chromatography (IC) paired with either a conductivity detector (IC-CD) or single quadrupole mass spectrometer (IC-MS) are essential techniques in environmental analysis. Previous research has demonstrated robust agreement when applying these methods to Antarctic ice cores and snow samples. However, the high concentrations of sea spray and mineral dust found in Arctic snow samples pose distinct challenges, that might impact the accuracy and precision of measurements, despite the existing efforts to minimise matrix effects. In particular, the higher amount of dust in the Arctic snow/ice samples could present an additional source for insoluble elements typically found in sea spray that is insoluble and thus undetectable by IC, causing a divergency between the results obtained from the two techniques. Therefore, it is crucial to comprehend how these factors influence the efficacy of ICP-QMS and IC techniques in polar research. This study provides a detailed comparison of these methods in quantifying sea salt species – sodium (Na), potassium (K), magnesium (Mg), and bromine (Br) – in surface snow samples collected at Svalbard. By cross-validating IC and ICP-QMS for these tracers, the study assesses each method's accuracy, sensitivity, and precision, providing valuable insights into their optimal application in polar research and climate studies.</div></div>","PeriodicalId":8064,"journal":{"name":"Applied Geochemistry","volume":"190 ","pages":"Article 106492"},"PeriodicalIF":3.1,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144548573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of High-Ozone Episodes Using a Chemical Metric Based on the Reactivities of Organic Precursors","authors":"Duy-Hieu Nguyen,&nbsp;Hsin-Cheng Hsieh,&nbsp;Sheng-Po Chen,&nbsp;Chang-Feng Ou-Yang,&nbsp;Chih-Chung Chang,&nbsp;Wen-Tzu Liu,&nbsp;Chieh-Heng Wang,&nbsp;Jia-Lin Wang","doi":"10.1029/2025JD043921","DOIUrl":"https://doi.org/10.1029/2025JD043921","url":null,"abstract":"<p>This study examines high-ozone episodes in an urban area of northern Taiwan influenced by local photochemical processes and transboundary pollution from the Asian continent. Long-term data sets from Photochemical Assessment Monitoring Stations and Air Quality Monitoring Stations were used to develop a photochemical metric based on volatile organic compounds ratios. We analyzed the ratio of ln(n-butane/ethane) versus ln(n-pentane/ethane) based on which we derived the <i>δ</i> value to assess the degree of regional air mass aging from a chemical reactivity perspective. In summer, extreme ozone events with low <i>δ</i> values are primarily driven by local photochemical activity. However, in fall and spring, the slightly higher <i>δ</i> values in some episodes signify the involvement of long-range transport (LRT) bringing in continental ozone and cooler air masses while local photochemistry remains active. The interaction between transported and locally produced ozone is pronounced during milder ozone episodes (100–120 ppbv). We further examined the <i>m,p</i>-xylene/ethylbenzene ratio as a complementary chemical indicator for characterizing ozone events with mild LRT. Slightly lower temperatures (below 28.8°C) are often accompanied by elevated nocturnal ozone levels (40–80 ppbv) and a less defined <i>m,p</i>-xylene/ethylbenzene ratio. Overall, high-ozone episodes (≥100 ppbv) are primarily driven by local photochemical processes. However, LRT can elevate the ozone baseline, particularly during spring and fall, when aged air masses bring in residual ozone leading to increased daytime ozone levels. These findings highlight how local photochemistry and regional transport shape high-ozone episodes emphasizing the value of chemical indicators for understanding air mass aging and ozone formation.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"130 13","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144536965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Strong Spatial Propagation Strength of Meteorological Droughts Exhibits in the Humid—Arid Transition Regions of Mainland China","authors":"Mingqiu Nie,&nbsp;Xin-Min Zeng,&nbsp;Shengzhi Huang,&nbsp;Ning Wang,&nbsp;Irfan Ullah,&nbsp;Wei Fang,&nbsp;Ganggang Bai,&nbsp;Zengxin Zhang,&nbsp;Jian Zhu","doi":"10.1029/2025GL115891","DOIUrl":"https://doi.org/10.1029/2025GL115891","url":null,"abstract":"<p>Spatial propagation strength (PS) is a critical characteristic of drought propagation, reflecting the degree of drought impact in one region relative to another. Here, we quantified PS of meteorological drought for the first time from the perspective of abnormal moisture transmission, and developed a novel framework, combining PS with the original complex network framework, to explore the topological characteristics of drought in mainland China (MC). The results show that non-positive PS may misrepresent dependency of synchronous droughts, and such instances are widespread in MC (60.4%). Based on dependent droughts, network coefficients derived from the framework indicate that high values of positive PS are predominantly distributed in the humid-arid transition zones. In these regions, droughts control most of the spatial propagation information, similar to droughts around the edge of the Tibetan Plateau. Our results highlight the importance of PS in drought propagation and could improve drought predictability.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 13","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025GL115891","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144537136","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Young Crustal Component in the Caroline Mantle Plume (Western Pacific Ocean)","authors":"Yuan Zhong,&nbsp;Ji Zhang,&nbsp;Sanzhong Li,&nbsp;Guo-Liang Zhang","doi":"10.1029/2024GL114031","DOIUrl":"https://doi.org/10.1029/2024GL114031","url":null,"abstract":"<p>The geochemical variability in oceanic island basalts is linked to Earth's deep mantle heterogeneity, with distinct mantle components whose origin is under debate. In this study, we found basalts from the Caroline Seamount Chain exhibit elevated δ⁵⁷Fe signatures. The association of high δ⁵⁷Fe with mildly depleted Nd–Hf isotope compositions indicates the involvement of a young crustal component in the Caroline plume, which was likely introduced into the Pacific Large Low Shear Velocity Province (LLSVP) by the subduction girdle surrounded Rodinia supercontinent about 600 million years ago. Similar recycled crustal components are also found in basalts from hotspots near the boundary of the Pacific LLSVP, including Hawaii and Galapagos, but not seen in basalts from hotspots centered in the Pacific LLSVP. We suggest the circum-Rodinia subduction could lead to such preferential appearance of young crustal materials, and consequently result in the zoned compositional structure of the Pacific LLSVP.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"52 13","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL114031","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144537139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}