bluuebunny/crossref_metadata_2025 huggingface dataset:
ReSiDue: A coupled rock physics and geochemical approach to understanding how rock-fluid interactions change permeability in volcanic systems
Authors: Kushnir Alexandra , Mikaelian Cindy , Mazzeo Andrea
Published: March 2024

Reactions between aqueous fluids and rocks result in secondary mineral formation – alteration – that can block permeable pathways in the Earth’s crust and change the hydraulic properties of geological systems. The propensity, extent, and timescales of rock alteration are therefore important controls on crustal permeability. However, understanding the intricate relationships that result in rock alteration and changes in permeability - including dissolution, transport, and redistribution of chemical compounds - represents a technical challenge and remains a key unsolved problem in the Earth sciences. As a result, we do not fully understand how these processes modify the structure of permeable channels and over what timescales they may hamper crustal fluid flow, limiting, for example, our ability to effectively model the efficiency of geothermal reservoirs or forecast volcanic eruptions. The SNSF-funded ReSiDue project – Redistribution of Silica and Deposition under a volcanic edifice - addresses how the redistribution of the most common compound in the Earth’s crust - silica (SiO2) - changes the permeability of rocks under volcanically relevant conditions. Silica alteration is ubiquitous in volcanic systems and results in changes to rock structure and thus hydraulic properties. However, the processes that lead to silica alteration remain understudied, especially at high temperatures, because they involve complex feedbacks between fluid-rock interactions and petrophysics. Using a mix of detailed petrophysical, microstructural and geochemical characterization, and water-rock interaction experiments, we are quantifying 1) the physical and chemical conditions promoting silica alteration in volcanic edifices, 2) how fluid-flow pathways in rocks change over time as a result of silica alteration, 3) how these changes modify permeable flow, and 4) on what timescales these processes are active. The newly operational High temperature Reactive flOw permeabiLity Device – HAROLD – allows for in situ monitoring of permeability evolution over time, during reactive flow. This apparatus can operate at temperatures up to 500°C and confining and pore fluid pressures of 100 MPa and 20 MPa, respectively, allowing us to target conditions relevant to volcanic edifices and shallow geothermal reservoirs. This systematic understanding of how silica alteration changes the permeability of volcanic rocks will help refine volcanic outgassing models, with potential application to risk assessment and hazard mitigation efforts. However, beyond volcanology, this project sets the infrastructural, experimental and analytical foundation needed to more broadly study the relationships between rock-fluid interactions and crustal fluid flow, including in geothermal systems.
Remote Sensing-Enhanced Assessment of Groundwater Potential Zones in the Wadi Waj, Western Saudi Arabia: An AHP-GIS Framework
Authors: Al-Areeq Ahmed , Benaafi Mohammed , Al-Suwaiyan Mohammed , Chowdhury Shakhawat , Aljundi Isam
Published: March 2024

This study represents a thorough investigation into groundwater potential within a substantial basin situated in the western region of Saudi Arabia. Fueled by the escalating demand for potable water, agricultural irrigation, and industrial applications, a profound understanding of the capacity of underground water reservoirs, or aquifers, is imperative. Leveraging advanced techniques, this research integrates Geographic Information System (GIS), the Analytic Hierarchy Process (AHP), and remote sensing data to conduct a comprehensive assessment and mapping of groundwater potential zones (GWPZ). The evaluation process involves the meticulous analysis of several thematic layers: geology, slope, land use, lineament densities, soil characteristics, drainage density, and rainfall. The AHP method is then employed to assign weights to each class within the thematic maps, considering the unique characteristics of each parameter and its consequential influence on water potential. The resultant GWPZ map classifies the region into five distinct zones: very low, low, moderate, high, and very high, providing a nuanced understanding of groundwater potential across the basin. By leveraging the synergy of GIS, AHP, and remote sensing data, this research contributes valuable insights into the nuanced intricacies of groundwater potential assessment. The developed methodology can be adapted for similar regions globally, emphasizing the importance of integrating cutting-edge technologies to address critical challenges associated with sustainable water resource management amidst increasing global demands. The findings of this research can inform decision-making processes for sustainable water resource management in the basin, helping to prioritize areas for groundwater development and conservation efforts.
Investigation of Water Flow in Single-Layer and Multi-Layered Constructed Technosols of Green Roof
Authors: Snehota Michal , Sobotkova Martina , Petreje Marek , Heckova Petra , Wahab Razbar , Rybova Barbora , Jelinkova Vladimira
Published: March 2024

The performance of constructed soil systems with multiple layers for green roof applications was evaluated in this study. These systems may have advantages over single-layered soils, such as reduced evapotranspiration, increased infiltration, contaminant removal, and plant support. However, the water and solute fluxes across the interfaces between different layers are poorly understood. An experimental set-up of 18 rhizoboxes with two and four-layered soil systems was built on the roof in an open-air setting. Two green roof substrates were used to create the layers. The water balance components were measured to assess the hydraulic functioning of the soils. Invasive and noninvasive methods were applied to investigate the phenomena of capillary barrier, finger flow, and air entrapment in the multi-layered soils. Retention curves of substrates were determined. A modeling approach for water and solute fluxes in natural soils was adapted to multi-layered constructed soils. The results of the first six months of monitoring are presented and discussed. The study should provide valuable insights into the design and management of green roofs with multi-layered soils.
Microclimate change: the hidden driver of species redistributions
Authors: Lembrechts Jonas , network SoilTemp
Published: March 2024

Recent research has shown that the impacts of climate change on terrestrial species distributions are more complex than expected. Species distributions are showing significant delays in responses, or have shifted in unexpected directions. Scientists have identified several mechanisms that could explain these mismatches, including slow population dynamics, habitat fragmentation, and biotic interactions that limit the spread of species. Yet, one crucial aspect remains largely overlooked: we first need relevant high-resolution baseline climate change data to accurately answer this question.Indeed, organisms respond to microclimate change, which can differ significantly from macroclimate change. We know that local temperatures near the ground or below vegetation can be several degrees different from weather station data. However, it remains a mystery how quickly these microclimates are changing, as this depends as much on climate change as on land use changes.In this talk, we will explore how the SoilTemp-database, a global database of more than 75,000 in-situ measured microclimate time series, can be used to improve global microclimate products and ultimately provide better estimates of microclimate change. By applying these products to improve our estimates of species distributions, we can better understand the impacts of climate change on biodiversity, crucial for adjusting biodiversity management to a rapidly changing world.
Timing and geodynamical setting of Paleoproterozoic events in the Birrimian of the West African Craton: Insights from the Hounde Greenstone Belt (SW Burkina Faso)
Authors: Bruguier Olivier , Bosch Delphine , Caby Renaud , Baratoux Lenka , Jessell Mark
Published: March 2024

This study presents geochemical (major and trace elements, Pb-Sr-Nd isotopes on whole rocks) and geochronological (U-Pb on zircon) analyses on granitoids and volcanics from the Hounde Greenstone Belt (HGB). The HGB is one of the three Greenstone Belts outcropping in the southwestern part of Burkina Faso with, from east to west, the Boromo, Houndé and Banfora Greenstone belts. All three greenstone belts are separated by granitic domains and are mined for gold. In the HGB, the preserved sequence is constituted by a 6 km thick basaltic and gabbroic pile followed upward by intermediate (andesite) to felsic (rhyolite) volcanics with intercalated volcaniclastic and sedimentary material. Fine-grained sediments are more and more abundant upward. The HGB is limited on the East by the N-S Boni shear zone, which controlled deposition of “Tarkwaian-type” detrital sediments (conglomerate, sandstones and phyllites).Geochemical analyses indicate that the oldest dated plutonic samples (2195 ± 6 and 2183 ± 7 Ma) have a trondhjemitic affinity and metaluminous or peraluminous character. Similar ages at 2172 ± 5 and 2191 ± 5 Ma were also obtained on volcanics (andesite and rhyolite) from within the HGB indicating coeval development of GB and basement rocks. The trondhjemite have geochemical characteristics consistent with magma production in a convergent plate setting and the 2.20 – 2.17 Ga period is interpreted as corresponding to arc build-up and thickening of the arc crust. Cross-cutting leucocratic veins in the trondhjemite indicates partial melting of the arc crust at 2144 ± 6 Ma, which may be related either to a regional metamorphic event or triggered by the gradual thickening of the crustal section. Granites and granodiorites (and their volcanic equivalents) yield younger ages in the range 2132 ± 3 Ma to 2095 ± 9 Ma, and geochemical features typical of volcanic arc granites although the youngest granitoids, in the 2120 – 2100 Ma range, indicate a syn-collisional setting. Nd isotope data show large variations (eNd ranging from +0.7 to +14.5) and a broad general trend of increasing eNd values with decreasing ages. This trend may reflect increasing proportions of juvenile mantle-derived material to the source regions of the younger granitoids. However some samples have significantly older TDM model ages ranging from 2310 to 2430 Ma suggesting the involvement of early Birrimian components that could have been added to the source regions, either by assimilation at lower crustal levels or by sediment subduction.
The potential of Volcanic Pozzolan from Iceland (VPI) in concrete production to reduce the carbon footprint
Authors: Costa Diego , Heinonen Jukka , Finger David , Bjarnadóttir Sigríður , Ögmundarson Ólafur , Wigum Börge , Þorsteinsson Björn , Adolfsdóttir Helga
Published: March 2024

The concentration of atmospheric carbon has overpassed 420ppm calling for urgent action to mitigate climate change and remain below the 1.5-degree warming agreed in the Paris climate agreement. The construction industry, with energy consumption included, is with about 40% a significant contributor to the global carbon emissions. Within concrete production, cement accounts for 90% of the emissions. Notably, cement production alone accounts for 8% of global carbon emissions.Fly ash is amongst the most used of all Supplementary Cementitious Material (SCM). However, its availability is becoming an issue since many coal power plants are shutting down in Europe. Moreover, its environmental profile is questionable. Fly ash is a side product of a carbon intensive industry. Nonetheless, no environmental load has been allocated to it until now.This study investigates how Volcanic Pozzolan from Iceland (VPI) in concrete compares to traditional concrete and VPI to fly ash, as well as the potential of reducing carbon emissions in concrete production by using VPI as SCM and substitute for cement.To assess the environmental impacts of VPI and fly ash in cement production, we conducted a Life Cycle Assessment (LCA). For this purpose, we used the GaBi software and relied on primary data from the developers, Heidelberg Materials, and secondary data from the Ecoinvent database.Our preliminary results reveal that the utilization of VPI as SCM yields an important reduction in carbon emissions compared to Ordinary Portland Cement (OPC) concrete. This notable decrease in carbon footprint positions VPI as a compelling alternative for sustainable concrete production. Two primary factors support this assertion: i) preliminary tests affirm the comparable properties of VPI concrete to OPC, and ii) the diminishing availability of fly ash in Europe necessitates alternative sources, often located at considerable distances, thereby escalating transportation-related emissions.In conclusion, the integration of VPI emerges as a viable strategy to combat climate change and curtail the carbon footprint of the concrete and construction industry. This initiative aligns with global environmental objectives outlined in the Paris Agreement, United Nations Climate Change Conference, and the Nordic commitment to carbon neutrality by 2040. Embracing VPI as a sustainable alternative in concrete production reflects a positive stride towards achieving these critical environmental milestones.
Environmental consequences resulted from the oil depots’ deterioration by the RF’s missile attacks
Authors: Karamushka Viktor , Boychenko Svitlana , Havryliuk Ruslan
Published: March 2024

Since the beginning of the full-scale aggression on 24 February, 2022, primary targets for missiles attacks of Russian Federation were the objects of energy sector of Ukraine.  According to the reports of the State Environmental Inspection of Ukraine, more than 30 units comprising oil depots, product warehouses, refineries, gas stations were destroyed during the March 2022 only. Most of these objects were oil depots.  The purpose of this investigation was an environmental impact assessment of the missile attacks on the petroleum depots. We analysed the cases of destruction of oil depots in Okhtyrka (Okhtyrkanaftogaz), Chernihiv (Aystra), Kalynivka (KLO) and Kryachki (AS Investment), which were completely or partially destroyed. The results of field research, satellite monitoring data, data of the State Environmental Inspection and other state bodies were used for the analysis.As a result of the attacks, a significant part of petroleum products burned, which caused atmospheric air pollution by combustion products (carbon monoxide (CO), carbon dioxide (CO2), soot (C), nitrogen dioxide (NO2), sulphur dioxide (SO2), marginal hydrocarbons (С12-C19)). The estimated volume of emissions at the Kalynivka oil depot alone is more than 30 metric tons of carbon dioxide equivalent (mt CO2e). Spills of oil products caused pollution and partial burning of the surface layer of soils (at all bases) and penetration of oil products into groundwater with further migration over considerable distances (Kalynivka oil depot). The article presents the results of the monitoring and quantitative assessment of the soil and ground water pollution by oil derivatives as well as plant biodiversity assessment on the territory suffered from the incidents.
Large-scale climate modes dominate recent ice mass and elevation variations in much of East Antarctica
Authors: King Matt , Ayabilah John Bright , Christoffersen Poul , Vance Tessa , Udy Danielle
Published: March 2024

Large-scale climate modes have recently been shown to dominate the non-linear variability of Antarctic mass over the last 20 years. We explore these results in further detail in the context of East Antarctica and expand on this work to report on new analyses of Antarctic elevation change from satellite altimetry. Altimetric measurements provide insights into spatial variation of these signals at two orders of magnitude higher spatial resolution than mass-change measurements from GRACE, allowing for resolution of variability at sub-glacier scale. Exploring the same period as the GRACE data (2002-2021) we show that about 75% of the variance of the Totten Glacier elevation can be explained by a combination of Southern Annular Mode (SAM) and ENSO. Denman Glacier shows almost no non-linear variance over 2002-2021 but about 30% of the present signal is explainable by SAM with no evident ENSO response. Despite this, much of the signal is not focused on the outlet glaciers but diffusely spread across the interior, consistent with surface mass balance. We show that much of this signal can be explained by models of firn densification, although different models have different levels of agreement with the data at relevant decadal periods. We will show detailed results for Wilkes Subglacial Basin and Dronning Maud Land.
Implementation of the Random Forest Algorithm for Magnitude Prediction in the Matano Fault Indonesia 
Authors: Madona  , Rosid Mohammad Syamsu , Handoko Djati , Riama Nelly Florida , Saiful Deni
Published: March 2024

Studying earthquake prediction is an interesting academic area. Earthquakes are classified as natural disasters that have the potential to inflict significant damage.  The magnitude of an earthquake provides substantial benefits, both immediately after the event and in the future, for risk assessment and mitigation. This study employs the Random Forest algorithm to predict the magnitude of earthquakes occurring on the Matano Fault in Sulawesi, Indonesia. The prediction is derived from the historical seismic data collected between 1923 and 2023, obtained from the BMKG and USGS Catalogs. The area of interest is situated along the Matano Fault in Sulawesi, Indonesia, with coordinates ranging from 2.99°S to 1.66°S and from 120.50°W to 122.47°W. The dataset comprises six attributes and is split into training and testing sets at a ratio of 70% and 30%, respectively. The variables employed in this investigation encompass origin time, latitude, longitude, magnitude, and magnitude type.  The investigation yields an RMSE score of 0.1929. Overall, the prediction model has outstanding performance, with a high degree of accuracy in predicting values that quite match the actual values. Additionally, the Root Mean Square Error (RMSE) value is 0.1929, indicating a low level of error in the predictions. this work attempts to propose an alternative approach, characterized by a straightforward and practical technique, to solve problems in the geophysics field, for instance in the area of earthquake prediction.
Underestimated ENSO Asymmetry and Zonal Currents over the Equatorial Western Pacific in OMIP2 experiments 
Authors: Li Jin , Yu Yongqiang
Published: March 2024

The El Niño-Southern Oscillation (ENSO) is one of the most significant integrated interannual oscillations with coupled atmosphere-ocean processes in the tropical Pacific. Most coupled climate models are weak in depicting ENSO asymmetry over equatorial Pacific subsurface. And it is still unclear how the stand-alone ocean model contributes to this bias. In this study, we found that most ocean models from the Ocean Model Intercomparison Project (OMIP), driven by JRA55, underestimate the asymmetry of ENSO in the equatorial western Pacific subsurface. We investigated the primary factors contributing to this bias using composite analysis and diagnostics, and found that the weaker responses in upwelling and stronger responses in downwelling to westerly and easterly wind stress anomalies in the models are mainly responsible for the bias. Furthermore, the underestimation of zonal current variability over western Pacific subsurface, influenced by the gradient of mean state of sea surface height along the equatorial Pacific, leads to an opposite relationship between asymmetry and the zonal component of nonlinear dynamic heating in the western Pacific subsurface comparing to that in the eastern Pacific subsurface. Our study emphasizes the importance of accurately modeling ocean currents to capture the characteristics of ENSO nonlinearity and highlights the significance of nonlinear dynamic responses to external forcing.
Exploring Variable Synergy in Multi-Task Deep Learning for Hydrological Modeling
Authors: Ouyang Wenyu , Gu Xuezhi , Ye Lei , Liu Xiaoning , Zhang Chi
Published: March 2024

Despite advances in hydrological Deep Learning (DL) models using Single Task Learning (STL), the intricate relationships among multiple hydrological components and model inputs might not be comprehensively encapsulated. This study employed a Long Short-Term Memory (LSTM) neural network and the CAMELS dataset to develop a Multi-Task Learning (MTL) model, predicting streamflow and evapotranspiration across multiple basins. An optimal multi-task loss weight ratio was determined manually during the validation phase for all 591 selected basins with streamflow data-gaps under 5%. During test period, MTL showed median Nash-Sutcliffe Efficiency predictions for streamflow and evapotranspiration at 0.69 and 0.92, consistent with two STL models. The MTL's strength appeared when predicting the non-target variable, surface soil moisture, using probes derived from LSTM cell states—representative of the internal DL model workings. This prediction showed a median correlation coefficient of 0.90, surpassing the 0.88 and 0.89 achieved by the streamflow and evapotranspiration STL models, respectively. This outcome suggests that MTL models could reveal additional rules aligned with hydrological processes through the inherent correlations among multiple hydrological variables, thereby enhancing their reliability. We termed this as "variable synergy," where MTL can simultaneously predict varied targets with comparable STL performance, augmented by its robust internal representation. Harnessing this, MTL promises enhanced predictions for high-cost observational variables and a comprehensive hydrological model.
Synchronous Decadal Climate Variability in the Tropical Central Pacific and Tropical South Atlantic
Authors: Liu Chao , An Soon-Il , Kim Soong-Ki , Stuecker Malte , Zhang Wenjun , Jin Fei-Fei , Park Jae-Heung , Jiang Leishan , Xue Aoyun , Geng Xin , Park Hyo-Jin , Yang Young-Min , Kug Jong-Seong
Published: March 2024

The El Niño-Southern Oscillation (ENSO), the strongest interannual climate signal, has a large influence on remote sea surface temperature (SST) anomalies in all three basins. However, a missing map piece in the widespread ENSO teleconnection is the Equatorial Atlantic, where the ENSO footprint on local SST is less clear. Here, using reanalysis data and partially coupled pacemaker experiments, we show that the tropical Pacific SST anomalies, manifested as a Central Pacific (CP) ENSO-like structure, synchronize the tropical South Atlantic (40°W-10°E, 15°S-0°) SST anomalies over the last seven decades, but on a quasi-decadal (8-16 year) timescale. Such a decadal connection is most evident during the boreal spring-summer season, when the CP ENSO-like decadal SST anomalies induce a cooling of the South Atlantic SSTs through atmospheric teleconnections involving both Southern Hemisphere extratropical Rossby waves and equatorial Kelvin waves. The resulting subtropical South Atlantic low-level anticyclonic circulation and easterlies at its northern flank cause local ocean-atmosphere feedback and strengthen the Pacific-to-Atlantic teleconnections. In contrast, the concurrent tropospheric temperature teleconnection is less destructive to the above Atlantic SST response due to the weaker and more west decadal Pacific SST anomalies compared to the interannual ENSO counterpart. Pacific-driven coupled simulations reproduce key observational features fairly well, while parallel Atlantic-driven simulations show little forcing into the Pacific. Our results show that the tropical Central Pacific is an important source of decadal predictability for the tropical South Atlantic SST and the surrounding climate.
The reservoir development model of different lithology basement rocks in Erlian Basin，Northeast China.
Authors: Shen Che , Jiang Youlu
Published: March 2024

In sedimentary basins, the basement typically exhibits non-conformable contact with the overlying sedimentary strata. The basement surface undergoes a complex history of uplift, weathering, erosion, and sediment burial, all of which contribute to its reservoir structural composition. This study integrates microscopic observations, macroscopic well logging data, and seismic data to analyze the physical and weathering effects on the basement reservoirs with different lithologies and distinct structural features within the Erlian Basin. The basement rock types in the study area mainly include tuff, limestone, granite, cataclastic rock, and the basement has been affected by weathering, denudation, dissolution and structural transformation during the evolution of the basin. The basement has been subjected to long-term tectonic modification, forming network cracks on the macro scale and micro-fractures on the micro scale. Weathering and underground fluids along the fractures dissolve the matrix of tuff rock, feldspar in granite and limestone, thus forming dissolution fractures and dissolution pore in the basement rocks. These fractures and dissolution pores make the porosity and permeability of the basement rocks surface show obvious heterogeneity. According to the microstructure and physical property changes, the structure of different lithology basement surface is analyzed. Among them, the surface of the tuff basement rock has undergone multi-stage volcanic eruptions and weathering leaching, with a structure of multi-stage ancient weathering crust reservoir superposition, and the porosity and permeability of the gentle slope at the structural high part is large. The surface of granite and cataclastic rock basement is controlled by tectonic activity, weathering leaching, and formation fluid action. The double-layer structure comprises the top paleo-wind crust reservoir and the middle and lower fracture dissolution reservoirs, exhibiting high porosity and permeability in the elevated structural positions and the region proximate to the fault zone. Controlled by karstification, tectonic activity, and ancient landform, the limestone basement rock surface displays longitudinal variations in reservoir storage space types, featuring a structure with multiple sets of vertically arranged reservoirs, particularly characterized by high porosity and permeability in elevated structural positions and near fault zones. The concept and results of this work can be used for future studies on unconventional basement reservoirs in other regions.
Structural Deformation Responses In the Neoproterozoic Stratum to the Multiple Orogenesis Around the Southwestern Margin of the North China Craton
Authors: Chang Yinglei , Luo Jinhai , Chen Zhuo , Chen Guanxu
Published: March 2024

The structural deformations within the Neoproterozoic stratum along the southwestern margin of the North China Craton (NCC) offer a noteworthy illustration of the interactive relationship between structural deformation and orogenesis. Utilizing dating results from detrital zircons analyzed with U-Pb LA-ICP-MS and regional geological data, the sedimentary age of the epimetamorphic rocks, which outcrop in the southwestern margin of the Ordos Block, is constrained to the interval of 900-635 Ma. These rocks were deposited within a sedimentary basin encompassed by the Ordos Block, North Qinling orogenic belt, and Longshan structural belt. All three tectonic units contributed detritus, and the presence of interlayers of intraclast conglomerate suggests that the sedimentary setting experienced disturbance due to peripheral tectonic activities. Three episodes of structural deformation (D1, D2, and D3) are recognized in the epimetamorphic rocks. The D1 deformation is primarily characterized by parallel-bedding extensional deformation, likely induced by the opening of the Erlangping-Huluhe-Chenjiahe back-arc basin in the early stage of the Early Paleozoic. The D2 deformation is predominantly manifested as plastic compression deformation, likely induced by the closure of the Erlangping-Huluhe-Chenjiahe back-arc basin in the late stage of the Early Paleozoic. The D3 deformation is primarily characterized by a few parallel folds formed at the shallow-seated tectonic level under the compressional tectonic setting resulting from the closure of the Mianlue Ocean during the middle Triassic. It is suggested that the study area was located at the margin of the Ordos Block during the Mesoproterozoic, and the Longshan structural belt likely existed as an independent block at that time.
Key words: the Southwestern Margin of the Ordos Block, Neoproterozoic, detrital zircon U-Pb age, structural deformation, Longshan structural belt
Coupled processes of groundwater dynamics and land subsidence in Tianjin, China after the South-to-North Water Transfer Project
Authors: Su Guangli , Xiong Chunbao
Published: March 2024

Over the past six decades, the groundwater became the main source of water following a serious shortage in surface water in the North China Plain (NCP). This resulted in a large area of groundwater level (GWL) depression and land subsidence cones. To address this crisis, the Chinese government implemented the largest water transfer project in human history—the South-to-North Water Transfer Project (SNWTP), the middle route of which was completed and put into operation in 2014. In this context, Tianjin, one of the main beneficiaries of this project, has been relieved from water shortages and begun to implement Groundwater Management Plans (GMP) such as water source conversion and ecological water replenishment for rivers and lakes since 2018, which undoubtedly have a significant effect on the groundwater recovery. Meanwhile, this provides a good case for studying the coupled process of ground settlement and groundwater dynamics, especially the soil deformation pattern driven by groundwater level (GWL) rebound. To analyze these issues in detail, field well data was collected to depict groundwater flow field. Moreover, geodetic data was also collated, including leveling, GPS, and InSAR, so that a vertical deformation field with high spatiotemporal resolution could be generated. The results reveal that the GWL of the third confined aquifer which is the main exploitation layer in Tianjin recovered significantly since 2018 with a rate of 2.1 m/yr. The area of GWL depression cones with a depth greater than 70 m has decreased by 85%. The dynamic deformation patterns indicate that the area of land subsidence cones in Tianjin has reduced significantly, accompanied by a sharply declining subsidence rate (decreased from -32.2 mm/yr to -4.5 mm/yr). Particularly, a significant poroelastic rebound has occurred in the Wuqing and Beichen districts since 2020, with the uplift rates in some areas exceeding 10 mm/yr. Furthermore, due to the delayed pore pressure dissipation in the aquitard, we find a time delay of 0.3–5.5 years between land subsidence and GWL time series, which is far less than that estimated by hydrogeological parameters, as the latter ignored the recharge and recovery capacity of the aquifer system. Finally, a evolution model in Tianjin was presented to illustrate interactive process among the deformation, pore pressure, and hydraulic head. In general, the SNWDP and the GMP has restored the pore pressure of aquifer, reduced the land subsidence, and alleviated the groundwater storage depletion of Tianjin, China.
Significant winter CO2 uptake by saline lakes on the Qinghai-Tibet Plateau
Authors: Shi Fangzhong , Li Xiaoyan
Published: March 2024

Direct measuring of CO2 flux remains challenging for global lakes. The traditional sampling and gas transfer models used to estimate lake CO2 fluxes are variable and uncertain, and ice-covered periods are often excluded from the annual carbon budget. Here, the first longtime (2013−2017) direct measurement of CO2 flux by eddy covariance system over the largest saline lake (Qinghai lake) in the Qinghai-Tibet Plateau (QTP) revealed that ice-covered period draws large amounts of CO2 from the atmosphere (−0.87 ± 0.38 g C m−2 d−1), a value more than twice the CO2 flux rate during the ice-free period (−0.41 ± 0.35 g C m−2 d−1). The total CO2 uptake by all saline lakes on the QTP was estimated to −10.28 ± 1.65 Tg C yr−1, an equivalent to approximately one third of the net terrestrial ecosystems carbon sink in QTP. Our results indicate large sink for CO2 in winter is controlled by both seasonal hydrochemistry processes and lake ice absorption in saline lakes. This research also demonstrates decreasing CO2 uptake from the atmosphere by saline lakes on the QTP, which may turn carbon sinks to carbon sources with future warming.
Observational analysis of a fog event in the oyashio extension area
Authors: Zhang Suping , Zhang Xin
Published: March 2024

The northwest Pacific is the most foggy oceanic area in the world. Low visibility in fogaffects navigation heavily, yet the synoptic processes of sea fog formation over open oceans remain unclear due to the lack of in-situ observations so far. In September 12-14, 2019, a Chinese arctic research vessel, XiangYanghong 01, captured a fog event in the cold Oyashio Extension (OE) area. The mechanism of the fog formation and maintenance is investigated in the present study based on the in-situ observations. The results show that the fog formation was influenced by both a synoptic-scale warm front in a midlatitude cyclone system and a local SST front (sea surface temperature front). Warm humid air was transported from south to north along with the warm front, which resulted in the near surface air becoming warmer and wetter in the OE area. The fact that the moistening effect was greater than the heating one led to the relative humidity increasing and close to saturation. On the other hand, the northward warmer air climbed upward when met the colder air mass over the OE water, thus forming a large-scale frontal temperature inversion. The bottom of the inversion dropped further affected by a sinking branch from a vertical circulation in the marine atmospheric boundary layer, and this vertical circulation was very likely to be induced by the local SST front.  The lowered inversion was conducive to fog droplets, once formed, to be confined near the sea surface. The fog layer was formed in the warm moist air on the cold flank of the SST front. The contributions of the background atmospheric warm front and the local SST front to fog formation is clarified and a relevant conceptual model is proposed, which are helpful for understanding of the physical processes in the formation of marine fog and for fog forecast in open oceanic area.
Terrane collision-induced subduction initiation: Mode selection and implications for western Pacific subduction system
Authors: Cui Fengyuan , Li Zhong-Hai
Published: March 2024

In the regime of plate tectonics, subduction of an oceanic plate generally terminates with the collision and accretion of continental terranes. Then, a new subduction zone may form in the neighboring oceanic plates, which is defined as the terrane collision-induced subduction initiation (SI). Based on the analyses of western Pacific subduction system in the Cenozoic, three types of collision-induced SI have been observed: subduction polarity reversal, subduction transference and far-field subduction. However, the dynamics and controlling factors of SI mode selection after terrane collision are not clear. In this study, a multi-terrane collision model has been conducted with variable rheological strength of continental terranes and different convergence velocities. The model results indicate that the relative strength of the terranes controls the SI mode selection, with the new subduction zone tending to form beneath weaker terranes. In addition, the higher convergence velocity can facilitate the collision-induced SI. An analytical study of force balance has been further conducted, which provides the mechanical explanation for the numerical prediction of weak overriding terrane as a favorable SI site. The numerical models and force balance analyses are further compared with the natural cases in the western Pacific subduction system. It indicates that subduction polarity reversal is the most favorable mode after terrane collision in the western Pacific, possibly due to the weakness of overriding plate during the preceding subduction-induced fluid/melt activity. This comprehensive study provides systematic constraints for the dynamics of collision-induced subduction jump, especially for the western Pacific subduction zones in the Cenozoic.
Lunar zircon from the Chang’e-5 landing site
Authors: Zhou Qin , Li Chunlai , Liu Jianjun , Wen Weibin , Liu Yu , Yang Saihong , Li Qiu-Li , Zhang Guangliang , Zhang Hongbo , Liu Bin , Liu Dawei
Published: March 2024

Zircon is one of the most important U-bearing minerals in the lunar geochronological studies. Since the first lunar zircon grains were analyzed in the early 1980’s, the majority of lunar zircon U(Pb)-Pb ages obtained from the Apollo missions in the last decades were distributed between about 4.4 and 3.9 Ga. Although the crystallization age of Chang’e-5 (CE-5) basalts were obtained from baddeleyite, zirconolite and tranquillityite, we attempted to search for lunar zircon grains from the collected CE-5 lunar sample for comparison with the previous studies. We scanned almost all polished sections of the CE-5 powder sample to identify lunar zircon grains, most of which are isolated grains or mineral clast in agglutinates and impact melt breccias. In our study, only one zircon grain was preserved in the lithic clast of CE-5 basalts after the scanning of hundreds polished sections. This zircon records a precise Pb-Pb isochron age of 2036 ± 19 Ma, which is the youngest crystallization age ever reported for lunar zircon geochronology. Combined with the petrology, mineralogy and geochronology, we have demonstrated that this zircon grain is the extreme fractional product from a non-KREEP mantle source similar to CE-5 basalt. Compared to the zircon from Apollo mission, the sampling site of CE-5 provides a new case that lunar zircon can crystallize from a variety of magmatic compositions in addition to KREEP-related magma. In the future, we plan to perform the studies of zircon grains from CE-5 samples in different lithologies and try to find the origin of these zircons grains.
Experimental Investigation on Dispersion Within Porous Media Influenced by Particle sizes and Pore-Scale Heterogeneity
Authors: Baek Jiyoung , Park Byeong-Hak , Rau Gabriel , Lee Kang-Kun
Published: March 2024

As heat tracing gains versatility in hydrogeological applications, precise thermal dispersion modeling becomes essential. However, limited experimental data for thermal dispersion, influenced by several factors such as particle size or shape, poses a challenge to the understanding of the relationship between flow velocity and thermal dispersion coefficient. To fill these gaps, the solute and heat tracer experiments were conducted using two different sizes of sand. Thermal and solute dispersion were analyzed by applying analytical models. We also systematically collected and revisited literature data to comprehensively interpret the influences of particle size, shape, and pore-scale heterogeneity on dispersion. The results exhibited that the solute and thermal dispersivity were comparable when the dispersion linearly increased to the velocity. However, within the transition regime (Pe < 5), a departure from linearity was observed (R2 < 0.9). The deviation was more pronounced in smaller particle size due to pore-scale heterogeneity arising from the complexity of pore network. Consequently, our findings emphasize the potential necessity for caution when modeling thermal dispersion based on solute dispersion within natural porous materials.Keywords: Particle size; Thermal dispersion; Pore-scale heterogeneity; Transition regime; Sandbox experiment AcknowledgementsThis work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (No. 2022R1A2C1006696). This work was also supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government(MSIT) (No. 2022R1A5A1085103). This work was also supported by the Nuclear Research and Development Program of the National Research Foundation of Korea (NRF-2021M2E1A1085200). 
A parameterization scheme for the floating wind farm in a coupled atmosphere-wave model (COAWST v3.7)
Authors: Deng Shaokun , Chen Shengli
Published: March 2024

Coupling Weather Research and Forecasting (WRF) model with wind farm parameterization can be effective in examining the performance of large-scale wind farms. However, the current scheme is not suitable for floating wind turbines. In this study, a new scheme is developed for floating wind farm parameterization (FWFP) in the WRF model. The impacts of the side columns of a semi-submersible floating wind turbine on waves are firstly parameterized in the spectral wave model (SWAN) where the key idea is to consider both inertial and drag forces on side columns. A machine learning model is trained using results of idealized high-resolution SWAN simulations and then implemented in the WRF to form the FWFP. The difference between our new scheme and the original scheme in a realistic case is investigated using a coupled atmosphere-wave model. Results indicate that the original scheme underestimates the power output of the entire floating wind farm in the winter scenario. On average, the power output of a single turbine is underestimated by a maximum of 694 kW (12 %). The turbulent kinetic energy decreases within the wind farm, with the greatest drop of 0.4 m2 s-2 at the top of the turbine. This demonstrates that the FWFP is necessary for both predicting the power generated by floating wind farms and evaluating the impact of floating wind farms on the surrounding environment.
The Design of a Low-Angle Active Leveling Device for Short-Period Ocean Bottom Seismometer
Authors: Yang Chin-Heng , Lin Ching-Ren , Gung Yuancheng , Lin Feng-Sheng , Chang Kun-Hui
Published: March 2024

In this study, we focus on developing a low-angle active leveling device of geophone for Ocean Bottom Seismometers (OBS). The deployment of OBS in varied underwater environments poses a significant challenge due to unpredictable terrains, which often affect the positioning and orientation of these instruments. In such scenarios, the role of a leveling device becomes crucial, especially for self-floating OBS. Most of the leveling devices are designed with a 360° range, resulting in high costs and limited versality, our approach is informed by previous OBS positional data, suggesting that a limited corrective angle is adequate for underwater conditions. Our innovative leveling mechanism resembles a joystick in its transmission system, topped with a platform to enhance versatility. The control rod below the platform is controlled by two DC motors combined with worm gears, adjusting the rod along the X and Y axes with an approximate corrective angle of 30 degrees. For seismic sensing, our system utilizes one vertical and two horizontal geophones, housed in a custom sensor box to ensure the three axes are orthogonal to each other. This design simplifies the complexity of parts, combining off-the-shelf and custom components, offering a significant size and cost advantage. We have also tested its performance, with a focus on eliminating signal interference from resonance frequencies and assessing the system's stability. This includes a comparative analysis with older leveling mechanisms.
Years of satellite record reveals high level velocity and mass discharge in Totten Glacier, East Antarctica
Authors: Li Rongxing , Cheng Yuan , Chang Tian , Gwyther David E. , Forbes Martin , An Lu , Xia Menglian , Yuan Xiaohan , Qiao Gang , Tong Xiaohua , Ye Wenkai
Published: March 2024

East Antarctic Ice Sheet (EAIS) has an overall balanced or slightly positive mass balance. However, Wilkes Land and Totten Glacier (TG) in EAIS have been losing ice mass significantly since 1989. There is a lack of knowledge of long-term mass balance in the region which hinders the estimation of its contribution to global sea level rise. We reconstruct ice flow velocity fields of 1963–1989 in TG from the first-generation satellite images of ARGON and Landsat-1&4, and build a five decade-long record of ice dynamics. Based on these velocity maps, we show that this acceleration trend in TG has occurred since the 1960s. Combined with recently published velocity maps, we find a persistent long-term ice discharge rate of 68 ± 1 Gt/y and an acceleration of 0.17 ± 0.02 Gt/y2 from 1963 to 2018, making TG the greatest contributor to global sea level rise in EA. We attribute the long-term acceleration near grounding line from 1963 to 2018 to basal melting likely induced by warm modified Circumpolar Deep Water. The speed up in shelf front during 1973–1989 was caused by a large calving front retreat. As the current trend continues, intensified monitoring in the TG region is recommended in the next decades.
Projected decline of CO2 fertilization effects on vegetation carbon sequestration in India
Authors: Bejagam Vijaykumar , Sharma Ashutosh , Wei Xiaohua
Published: March 2024

The increase in vegetation productivity in India (net primary productivity; NPP) has been observed in recent decades; however, substantial uncertainty exists about the continued strength of these land carbon sinks under climate change. The enhanced NPP is driven by the strong positive carbon-concentration feedback (CO2 fertilization effect; CFE), but the temporal dynamics of this feedback are unclear. Using the carbon fluxes from the multiple Earth System Models (ESMs) of Coupled Model Inter-comparison Project (CMIP6), we showed an increasing trend in NPP would continue under climate change with projections of NPP to 2.00 ± 0.12 PgCyr-1 (25% increase) during 2021-2049, 2.36 ± 0.12 PgCyr-1 (18% increase) during 2050-2079, and 2.67 ± 0.07 PgCyr-1 (13% increase) during 2080-2099 in Indian tropic forests under SSP585 scenario. This suggests a significant decline in the growth rate of NPP in future periods. To understand the feedbacks that drive the NPP increase, we analyzed the relative effects of CFE and warming. We compared the simulations from the biogeochemical coupled model (BGC) from ESMs, which exclude the warming effects, with the fully coupled model, which includes both CFE and warming effects. The BGC model projected a 74.7% increase in NPP by the end of the century, significantly higher than the 55.9% increase projected by the fully coupled model. This shows that the consistent increase in the NPP was associated with the rise in atmospheric CO2. More importantly, results reveal that the decrease in the growth rate of NPP was due to the decline in the contribution of CFE across the different vegetations at a rate of -0.62% 100 ppm-1. Such a decline could be attributed to nutrient limitation, negative responses to high temperatures, droughts, heat waves, etc. Additionally, statistically significant shifts in the strength of carbon sinks (at a rate of -1.15% per decade) were identified in abating anthropogenic CO2 emissions. These shifts in land carbon sinks can potentially exacerbate global warming and impose additional challenges on our collective efforts to meet climate policy targets.