bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of LAI assimilation by LDAS-Monde on modelled photosynthesis and respiration in the ISBA land surface model
Authors: Bonan Bertrand , Decharme Bertrand , Delire Christine , Calvet Jean-Christophe
Published: February 2023

Land Data Assimilation Systems (LDASs) aim to monitor the evolution of land surface variables (LSVs). They were initially designed with a focus on soil moisture and temperature. Since then, the focus has increasingly expanded towards vegetation monitoring with the assimilation of Leaf Area Index (LAI) or other vegetation-related data. LDAS-Monde, the offline land data assimilation system (LDAS) developed by Météo-France’s research centre (CNRM), has been a pioneer in that domain, as it can assimilate LAI while updating directly soil moisture especially in the root-zone area. This approach has also demonstrated several times its ability to improve the simulation of Gross Primary Production (GPP) by the ISBA (Interactions Soil-Biosphere-Atmosphere) land surface model, included in LDAS-Monde.In this work, the impact of assimilating LAI on GPP and net ecosystem exchange (NEE) is assessed with two versions of the ISBA land surface model: the classical ISBA A-gs involved currently in LDAS-Monde and the more sophisticated ISBA-Carbon Cycle (ISBA-CC) version. ISBA A-gs simulates the assimilation of carbon by photosynthesis following the work of Goudriaan et al. (1985) and Jacobs et al. (1996) while the ecosystem respiration is emulated with a simple Q10 formulation (Rivalland et al., 2005). ISBA-CC uses the same approach for photosynthesis but by modelling all biomass reservoirs (such as roots or wood) can calculate more accurately autotrophic respiration. ISBA-CC also involves a heterotrophic respiration calculated by a soil carbon module. The comparison and the impact assessments are carried out at site levels using the PLUMBER2 datasets and at larger spatial scales using a new version of FLUXCOM GPP and NEE products.
Observation of the Large‐Amplitude andFast‐Damped Plasma Sheet FlappingTriggered by Reconnection‐InducedBallooning Instability
Authors: Zhang Yongcun , Dai Lei , Rong Zhaojin , Wang Chi , Reme Henri , Dandouras Iannis , Carr Chris , Escoubet Philippe
Published: February 2023

 In this study, we reported the large‐amplitude and fast‐damped flapping of the plasma sheet,which co‐occurred with magnetic reconnection. Data from the Double Star TC‐1 and Cluster satelliteswere used to analyze the features of the plasma sheet flapping 1.4 RE earthward of an ongoing magneticreconnection event. The flapping was rapidly damped, and its amplitude decreased from themagnetohydrodynamics scale to the subion scale in 5 min. The variation in the flapping period (from 224 to20 s) indicated that the source of the flapping had highly dynamic temporal characteristics. The plasma sheetflapping propagated duskward through a kink‐like wave with a velocity of 100 km/s, which was inagreement with the group velocity of the ballooning perturbation. A correlation analysis between themagnetic reconnection and plasma sheet flapping indicated that the magnetic reconnection likely facilitatedthe occurrence of ballooning instability by altering the state of plasma in the downstream plasma sheet. Inthis regard, the reconnection‐induced ballooning instability could be a potential mechanism to generatethe flapping motion of the plasma sheet. 
Seismic reflectivity of fractures: the impact of secondary connected fractures
Authors: Sotelo Edith , Rubino J. German , Barbosa Nicolas D. , Solazzi Santiago G. , Holliger Klaus
Published: February 2023

Fractures are ubiquitous through out the Earth's upper crust and dominate the mechanical and hydraulic properties of the affected rock masses. Indeed, open fractures act as fluid conduits and, commonly, flow is controlled by larger fractures, which are, in turn, likely to be connected to smaller ones. Therefore, fracture characterization is of paramount importance for many pertinent applications, such as geothermal energy production, CO2 sequestration, nuclear waste storage, and hydrocarbon exploration. Seismic reflection methods are useful tools for fracture characterization due to the generally high reflectivity that large fractures exhibit as a consequence of their strong mechanical contrast with the embedding intact background. The magnitude of this mechanical contrast is known to be strongly affected by fracture-to-background wave-induced fluid pressure diffusion (FPD). Conversely, the FPD effects associated with secondary connected fractures remain so far unexplored. We investigate the influence of FPD on the normal compliance and on the vertical incidence PP reflectivity of a large fracture that is hydraulically connected to smaller fractures. To this end, we use several models that consist of an infinite horizontal main fracture connected to multiple vertical secondary fractures of finite length. This fracture system is embedded in impermeable background. The individual models differ only with regard to the geometrical (e.g., length and aperture), and physical properties (e.g., permeability and bulk modulus) of the secondary fractures. For comparison, we also calculate the normal compliance and the reflectivity of an isolated infinite horizontal fracture. To assess the changes of fracture compliance due to FPD, we perform a vertical compressional oscillatory test over samples of the aforementioned models that include part of the fracture system and the embedding background. This test simulates the FPD effects that a vertically propagating P-wave generates between the main and secondary fractures. Specifically, the wave produces a pressure increase in the horizontal fracture that equilibrates as fluid flows into the secondary vertical fractures. Based on this oscillatory test, we compute the average of the vertical components of strain and stress over the main fracture, which we use to estimate its normal compliance. We then proceed to calculate the PP reflectivity at normal incidence using its inferred P-wave modulus. Our results show that both the compliance and the PP reflectivity of the main fracture increase as much as two-orders of magnitude in response to the presence of secondary fractures. We also find that the physical and geometrical properties of the secondary connected fractures have an influence on the normal compliance and reflectivity of the main fracture.
Snow depth in convection-permitting regional climate model simulations over southern Germany - ready for impact-related research?
Authors: Poschlod Benjamin
Published: February 2023

Snow dynamics are affecting the climate system, water cycle, ecology, human society, and infrastructure. Furthermore, the representation of snow on the land surface within regional climate models is crucial for the mass and energy balance in the modelled climate. Simulated daily snow depths of two high-resolution regional climate models, the WRF at 1.5 km resolution and the COSMO-CLM (CCLM) at 3 km resolution both driven by ERA5 reanalysis data are evaluated with 83 station observations in southern Germany during 1987 – 2018. Furthermore, based on the atmospheric output of CCLM, the hydrometeorological snow model AMUNDSEN is run at the point scale of the climate stations. In addition, the ERA5-Land dataset (9 km) complements the comparison as state-of-the-art reanalysis land surface product driven by the same atmospheric conditions of ERA5. ERA5-Land shows considerable deviations of grid cell elevation and station elevation (mean absolute error: 93 m) and moderate biases in air temperature (-0.3 °C) and precipitation (+19.1 %). However, there is a strong positive bias in mean winter snow depth (+3.5 cm) and snow cover duration (+33.3 d). The WRF simulation features a cold bias of -1.2 °C and moderate bias in precipitation (-5.2 %) during winter. This results in a slight overestimation of snow depth (+0.4 cm) and snow cover duration (+6.6 d). The CCLM strongly underestimates snow depth (-2.5 cm) and snow cover duration (-19.8 d), albeit a very good reproduction of air temperature (+0.0°C) and precipitation (+9.7 %). AMUNDSEN reverses the underestimations of the CCLM to an overestimation of snow depth (+2.2 cm), however improving the reproduction of snow cover duration (+6.4 d). All models fail to skilfully predict white Christmas.Extremes of snow dynamics such as annual maximum snow depths, maximum daily snow accumulation and melting are not well reproduced by ERA5L and CCLM. WRF and AMUNDSEN can improve the representation of extremes but still with considerable limitations.    In conclusion, the simulation of snow depths with WRF and AMUNDSEN can benefit from the finer resolution of the topography in the high-resolution climate models compared to ERA5-Land. However, even though driven by the same large-scale atmospheric conditions of ERA5, the four snow depth simulations vary by a huge margin. The high spatial resolution of convection-permitting climate models shows potential in reproducing the winter climate in southern Germany. However, the uncertainties within the snow modelling prevent a further straightforward use for impact research. Hence, careful evaluation is needed before any impact-related interpretation of the simulations, also in the context of climate change research.
Gastropod diversity dynamics at the Paleozoic–Mesozoic transition and the impact of the Carnian biotic crisis on gastropod diversity
Authors: Karapunar Baran , Nützel Alexander
Published: February 2023

During the transition from the Paleozoic to the Mesozoic, marine communities went through major changes in clade composition and proportions. A significant shift happened in the proportion between the Paleozoic Evolutionary Fauna and the Modern Evolutionary Fauna. The Permian-Triassic transition also marks the establishment of molluscs as the most diverse and dominant group in marine benthic environments. At the end-Permian, gastropods experienced a mass extinction as all other marine clades, but they showed a remarkable proliferation in the Triassic. As a result, the global species and genus diversity exceeded their maximum diversity during the Permian. However, not all gastropod clades contributed to the remarkable Triassic diversification. Similar to the shift in clade proportions between the Paleozoic and Modern Evolutionary Fauna, the clade proportions within Gastropoda changed at the Permian-Triassic transition as a result of differential diversification and selective extinction. The change in the proportional diversity of individual gastropod clades is most evident in the dwindling of the order Pleurotomariida (Vetigastropoda). Although Pleurotomariida was one of the most diverse and abundant Late Paleozoic gastropod groups, they diversified poorly during the Triassic recovery period compared to other groups. Gastropod diversity peaked in the Carnian (Late Triassic), but many newly evolved Carnian taxa could not pass the upper Carnian boundary, indicating an extinction event in the Carnian. A previous analysis of occurrence data in the Paleobiology Database (PBDB) indicates that among the marine clades, gastropods suffered most from the Carnian biotic crisis. Here, we analyze the generic range through data from the most comprehensive global Triassic gastropod list (2177 species, 429 genera) and the PBDB. The range-through data suggest high extinction rates in the Carnian (45%) compared to extinction rates during previous Triassic ages (5%). The Carnian extinction rates were higher than in the Rhaetian (35%). If singletons are excluded from the analysis, the Carnian still shows the highest extinction rate (16%) when compared with the Early and Middle Triassic ages (1–3%), but lower than in the Rhaetian (33%). Origination rates continuously decrease throughout the Triassic. Shareholder quorum subsampling analysis of the PBDB data indicates that generic extinction rates rose in the Carnian, peaked in the Norian and remained high in the Rhaetian. The analyses of both, range through and occurrence data show persistently high extinction rates throughout the Late Triassic. Altogether the Late Triassic biotic crises seem to impact gastropod diversity as much as the end-Permian mass extinction event.
Comparing Critical Source Areas for the Sediment and Nutrients of Calibrated and Uncalibrated Models in a Plateau Watershed in Southwest China
Authors: Chen Meijun , Janssen Annette B. G. , de Klein Jeroen J. M. , Du Xinzhong , Lei Qiuliang , Li Ying , Zhang Tianpeng , Pei Wei , Kroeze Carolien , Liu Hongbin
Published: February 2023

Controlling non-point source pollution is often difficult and costly. Therefore, focusing on areas that contribute the most, so-called critical source areas (CSAs), can have economic and ecological benefits. CSAs are often determined using a modelling approach, yet it has proved difficult to calibrate the models in regions with limited data availability. Since identifying CSAs is based on the relative contributions of sub-basins to the total load, it has been suggested that uncalibrated models could be used to identify CSAs to overcome data scarcity issues. Here, we use the SWAT model to study the extent to which an uncalibrated model can be applied to determine CSAs. We classify and rank sub-basins to identify CSAs for sediment, total nitrogen (TN), and total phosphorus (TP) in the Fengyu River Watershed (China) with and without model calibration. The results show high similarity (81%-93%) between the identified sediment and TP CSA number and locations before and after calibration both on the yearly and seasonal scale. For TN alone, the results show moderate similarity on the yearly scale (73%). This may be because, in our study area, TN is determined more by groundwater flow after calibration than by surface water flow. We conclude that CSA identification with the uncalibrated model for TP is always good because its CSA number and locations changed least, and for sediment, it is generally satisfactory. The use of the uncalibrated model for TN is acceptable, as its CSA locations did not change after calibration; however, the TN CSA number decreased by around 60% compared to the figures before calibration on both yearly and seasonal scales. Therefore, we advise using an uncalibrated model to identify CSAs for TN only if water yield composition changes are expected to be limited. This study shows that CSAs can be identified based on relative loading estimates with uncalibrated models in data-deficient regions.
Shocker: xenotime can date impacts
Authors: Joseph Cilva , Fougerouse Denis , J. Cavosie Aaron , K. H. Olierook Hugo , M. Reddy Steven , R. Quintero Raiza , Kennedy Allen , W. Saxey David , D.A. Rickard William
Published: February 2023

Constraining precise ages for impact events is crucial in establishing Earth’s history, and several geochronometers have been developed to date impacts. We present electron backscatter diffraction (EBSD), sensitive high-resolution ion microprobe (SHRIMP) and atom probe tomography (APT) data from shocked xenotime [(Y,HREE)PO4] collected from two impact sites to investigate the potential of xenotime as an impact geochronometer. A detrital xenotime grain from the Vredefort dome (South Africa) contains planar fractures, planar deformation bands and {112} twinning, the latter of which are diagnostic shock microstructures. However, APT analysis from the twin domains and also from the host yielded no evidence of Pb mobility at the nanometer scale during the impact. SHRIMP analysis (n=24) on the grain yielded a discordia with an upper intercept of 3136 ± 110 Ma and an imprecise lower intercept of 1793 ± 280 Ma. These correspond, respectively, to the bedrock age and a post-impact, cryptic terrane-wide fluid infiltration event. Three neoblastic grains from the Araguainha dome (Brazil) experienced partial to complete recrystallisation. The least recrystallised grain yields the oldest 238U/206Pb age of 479 ± 26 Ma, whereas a completely recrystallised neoblastic grain gave an age of 257 ± 11 Ma.  APT analysis on the latter grain showed different nanoscale features that shed light on Pb mobility during shock deformation and recrystallisation.  Based on observations of nanoscale Pb mobility and the correlation between recrystallisation and isotopic resetting, and prior published ages, we interpret 257 ± 11 Ma to date the impact event. These data confirm that recrystallised neoblastic xenotime is a useful impact geochronometer. 
Exploring the ‘Individual Treatment Effects’ (ITE) of Vegetation with Causal Inference on Soil Organic Carbon Prediction in Germany
Authors: Kakhani Nafiseh , Gläßle Thomas , Taghizadeh-Mehrjardi Ruhollah , Kebonye Ndiye Michael , Scholten Thomas
Published: February 2023

Carbon is an essential element and contributor to healthy soil conditions as well as ecological soil function and productivity. Additionally, carbon is a component of all plants and animals on the planet and is a necessary component of life. Natural vegetation serves as a significant but highly dynamic carbon sink. When vegetation is removed quicker than it can regenerate, for example by harvesting crops or timber, soil carbon is depleted. Thus, understanding the environmental effects and dynamics of loss of vegetation is a crucial prerequisite to turning our natural resource management from a carbon emitter to a carbon sink to avoid that and achieve sustainability. At the same time, the spatial distribution of soil organic carbon is also highly heterogeneous, with variations in climate, other soil characteristics, and land use/land cover affecting how our ecosystem reacts to the loss of vegetation. Thus, to effectively improve green metrics and contribute to the creation of future policies, it is required to conduct research on the changes in vegetation and their effect on soil organic carbon and provide regionally appropriate management advice. Here, in this research, our goal is to examine the "individual treatment effects" (ITE), which are a personalized or individualized effect estimation of one variable on the output, and utilize causal inference to address them.  Using the LUCAS dataset, we explore the heterogeneous treatment effect of percent tree coverage (PTC), as a parameter of the density of trees on the ground, on the soil organic carbon content in Germany. We do this by leveraging some parameters, such as climate data, land use/land cover information, and other information from the soil. We thus offer a data-driven viewpoint for focusing on sustainable behaviors and effectively increasing soil organic carbon content levels.
Cenozoic Tectonic Characteristics and Evolution of the Southwest Bohai Sea, China
Authors: Hao Ranran , Wang Yongshi , Wu Zhiping
Published: February 2023

Based on the detailed description of the fault system and the regional dynamic background of the study area, the Cenozoic structural development and evolution characteristics of the southwest Bohai sea and the migration law of the sedimentary-subsidence center were studied by using 3D seismic data and drilling data.The results show that the NW, NNE, NE and EW trending faults were mainly developed in the study area. The NW-trending faults were Cenozoic revived faults, which control the development of the NW-trending structural belt. The NNE-trending faults control the formation of the uplift, including Kendong fault, Gudong fault and Changdi fault, which all belong to co-direction shear faults of the Tan-lu fault zone, and have obvious strike-slip characteristics. The NE-trending faults and EW-trending faults were extensional faults, which further complicate the tectonic pattern. Under the control of the NNE-trending faults and near EW-trending faults, the sedimentary thickness of the Paleogene strata in the study area changed from thick in the south and thin in the north in the early stage to thin in the south and thick in the north in the late stage. In the sedimentary period of Es3, the uplift was highly segmented. The mountains were high and the surrounded lakes was deep, and the water bodies were connected between the depressions. During the sedimentary period from Es2 to Es1, the regional structure subsided and the lake area expanded. In the sedimentary period of Ed, it was high in the south and low in the north, and basically distributed regionally. After the Neogene, it finally became a unified whole to accept deposition. Generally, the overall evolution can be divided into four stages: ① Confined fault-depression stage of Ek to Es4；② Strong fault-depression stage of  Es3 to Es2；③Weak fault depression stage of Es1 to Ed；④ Weak extended depression stage of the Ng-Nm.
The Børglum fault, Sorgenfrei-Tornquist Zone, northern Denmark: a natural laboratory to investigate a hidden active intra-plate fault
Authors: Brandes Christian , Polom Ulrich , Winsemann Jutta , Sandersen Peter , Wu Patrick , Steffen Holger
Published: February 2023

Intra-plate faults are a special challenge in seismology, because of the long intervals between individual seismic events and the fact that such faults are often hidden below young sediments. This makes such faults difficult to detect and thus they can be the source of unexpected and fatal earthquakes. The Børglum fault is located in a slowly deforming area in northern Denmark and represents one of the northern boundary faults of the Sorgenfrei-Tornquist Zone. With a length of at least 250 km, it is capable to produce significant seismic events. Previous studies indicated that the Børglum fault is seismically active and this fuelled the demand for further analysis of the fault structure and its seismic hazard potential. Due to excellent coastal outcrops and available high-resolution DEMs, the Børglum fault is a perfect natural laboratory to analyse a hidden active fault. We present a multi-method approach based on outcrop analyses, shear-wave seismic reflection surveys, DEM analysis and numerical simulations of deglaciation-induced Coulomb failure stress change. The 2D seismic surveys show that the analysed segment of the Børglum fault is a complex fault system with a strike-slip component. This interpretation is based on positive flower structures on the seismic surveys, the presence of elongated mini-basins and the geometry of the drainage pattern in the study area. On the basis of soft-sediment deformation structures and disaggregation bands developed in Late Pleniglacial to Lateglacial marine and lacustrine deposits, we derive repeated phases of fault activity with earthquake magnitudes of up to M=7. The geometry of the drainage pattern in the study area indicates a close relationship between fault activity and topography. Based on the timing of fault activity and results from numerical simulations of deglaciation-related lithospheric stress build-up, it is likely that the Børglum fault is a glacially triggered fault and that the analysed part of the Sorgenfrei-Tornquist Zone is susceptible to glacially triggered fault reactivation.
Southern Ocean Emissions of DMS
Authors: Bhatti Yusuf , Revell Laura , Alex Schuddeboom , Adrian McDonald , Alex Archibald , Jonny Willaims , Erik Behrens
Published: February 2023

The biogeochemical behaviour of the Southern Ocean is extremely complex and dynamic. The processes that effect this behaviour in the Southern Ocean are highly dependent on radiative (e.g. sunlight), chemical (e.g. nutrient availability) and biological (e.g. phytoplankton) constraints. We aim to assess how the Southern Ocean DMS emissions change when the underlying biological constraints on the production of DMS are altered across time and space.Using a nudged configuration of the atmosphere-only Earth System Model, UKESM1-AMIP, we performed two sets of four different 10-year simulations from 2009 – 2018. One set tested four different seawater DMS data sets (Anderson et al. 2001, Hulswar et al. 2022, Lana et al. 2011, ), while the other set tested four different DMS sea-to-air flux parameterisations (Goddijn-Murphy et al. 2016, Liss and Merlivat 1986, Nightingale et al. 2000, Wanninkhof 2014). Our goal is to evaluate the variability in each stage for atmospheric DMS formation using four sea-to-air parameterizations and four oceanic DMS sources.Using a quadratic sea-to-air flux (Wanninkhof (2014) and Nightingale et al. (2000)) provides high transfer velocities in DMS, creating a positive bias across most areas of the Southern Ocean, except for biologically productive areas, such as the high latitude regions. Although the Southern Ocean atmospheric DMS average corresponds well to observations using quadratic formulas, large areas of the Southern Ocean have lower measured atmospheric DMS than model simulations. Linear relationships between wind and flux are shown to be more realistic. We find that there is a greater range of outcomes from the different sea-to-air flux parameterizations (2.84 TgS Yr-1 to 7.44 TgS Yr-1) than from the different oceanic DMS datasets (3.37 TgS Yr-1 to 7.29 TgS Yr-1). This work highlights the need for Earth System Models to include a sea-to-air parameterization that is more appropriate for DMS, and for oceanic DMS datasets to capture the time-varying nature of biological activity. Such improvements would help provide more accurate and realistic simulations of DMS in the Southern Ocean.
Deformations at Earth's dayside magnetopause under quasi-radial IMF: implications for the SMILE soft X-ray imaging
Authors: Yang Zhongwei , Guo Xiaocheng , Sun Tianran , Jarvinen Riku , Parks George K. , Huang Can , Li Hui , Wang Chi
Published: February 2023

The Solar wind Magnetosphere Ionosphere Link Explorer (SMILE) is a Chinese Academy of Science (CAS) and European Space Agency (ESA) collaborative science mission. Primary goals are investigating the dynamic response of the Earth’s magnetosphere to the solar wind (SW) impact via simultaneous in situ SW/magnetosheath plasma and magnetic field measurements, X-Ray images of the magnetosheath and magnetic cusps, and UV images of global auroral distributions.  Recently, soft X-ray emissions from SW charge exchange (SWCX) at Earth’s magnetosphere has been investigated using XMM-Newton observations (Zhang et al., ApJL, 2022). Their results reveal that heavy ions (e.g., O7+) have relatively discrete and intense spectral lines, which can be more easily captured by soft-X ray instrument. Another striking point is that the fitted X-ray flux emitted by the ion line is sensitive and correlated to some physical values of SW bulk speed and density. To obtain physical quantities self-consistently for SW heavy ions, a three-dimensional global hybrid model has been developing. Based on Zoltan, ParGrid, and Corsair, we have developing a three-dimensional hybrid model of the terrestrial magnetosphere combining several modules: e.g., open boundaries with different particle injectors, cold plasma model for the inner magnetosphere, magnetosphere-ionosphere coupling module, and vtk format IO etc. In this poster, we will present preliminary results on the global dynamics of proton and heavy ions from the Earth’s bow shock all the way to the magnetopause under quasi-radial IMF conditions. This research focuses on 3-D profiles of key physical parameters, such as the magnetosheath ion pressure and high speed jets. And the resulting deformation of the magnetopause also will be discussed. Heavy ion behaviors at above dynamic/kinetic structures may play important roles in their soft X-ray emission during the interaction between SW heavy ions and the Earth’s exosphere (mainly populated by neutral hydrogen atoms). Thence, we will represent and compare the soft-X ray imaging calculated by heavy-ion data and proton data, respectively.
Bauxite Reservoir Characteristics of Taiyuan Formation in Zhengning Area of Southwest Ordos Basin
Authors: Li hao yuan
Published: February 2023

Abstract：The bauxite reservoir of the new type Taiyuan Formation in Zhengning area, southwest of Ordos Basin, is affected by the karst palaeogeomorphology, and its thickness varies greatly.In order to systematically study bauxite, a new type of reservoir, based on core observation, microscopic thin section, high-pressure mercury injection, low-temperature nitrogen adsorption and other experimental methods, the petrological characteristics and pore structure characteristics of bauxite reservoir were studied, which further verified the significance of reservoir exploration.The results show that: (1) the upper and lower parts of the reservoir are bauxite mudstones, and the middle part is argillaceous bauxite. The relatively developed dissolution pores are the main storage space of bauxite; (2) The bauxite minerals of Taiyuan Formation are mainly composed of aluminum minerals and clay minerals. The main minerals are diaspore, kaolinite, illite and chlorite; (3) Bauxite reservoir space is mainly composed of intragranular dissolved pores, matrix dissolved pores, intergranular dissolved pores, intergranular pores and microcracks, with the pore size mainly between 20 and 200 μm； The pore diameter of the main throat of the reservoir is 150 nm~4μm. The pore structure is good, mercury removal efficiency is high, and the overall pore throat is mainly submicron to micrometer; The average physical porosity of the reservoir is 10.6%, and the average permeability is 4.04×10-3μm. Greater than 0.3×10-3μm 36% of them are above m, and the reservoir conditions are good.The research results provide a basis for bauxite gas exploration in Ordos Basin.
Toward a molecular level understanding of heterogeneous processes at atmospheric aerosol surfaces: ozonolysis of maleic acid droplets
Authors: Abouhaidar Rawan , Duflot Denis , Toubin Céline
Published: February 2023

Dicarboxylic acids are an essential component of tropospheric aerosols emitted directly or formed in chemical processes. The physiochemical properties and heterogeneous oxidation of aerosol particles containing maleic acid (MA) have been investigated using a mixed quantum and classical approach. The multiphase reactions of primary ozonide formation between the gas phase, the particle interface, and its bulk strongly influence the reaction mechanism and rate coefficients. Based on snapshots issued taken from molecular dynamics simulations, the mechanism of MA + O3 reaction is investigated in three different environments using ab initio method and density functional theory. The interfacial water molecules enhance the initial reaction step of MA + O3, with a larger rate constant at the air-water interface than in the gas phase. By assuming the Langmuir-Hinshelwood behavior and comparing it with the bulk, the ozonolysis of maleic acid mainly occurs in the bulk, and O3 diffusion in the bulk may be the limiting process.
Numerical modelling of intra-oceanic rifting: the rift-to-drift transition time frame
Authors: Rodrigues Nuno , Rosas Filipe , Duarte João , Gomes Afonso , Almeida Jaime , Riel Nicolas
Published: February 2023

Numerical modelling of rifting has been focused on cases involving extension and breakup of the continental lithosphere. However, the oceanic lithosphere has also been known to undergo rifting in specific geo-tectonic settings, as in the case of the Terceira ridge in the Azores triple junction (N-Atlantic). The rift-to-drift evolution of a segment of oceanic lithosphere potentially bears major implications for the Wilson cycle evolution of an oceanic basin, justifying the importance of carrying out the present numerical modelling study.We used the Underworld geodynamic code to carry out 2D numerical models of oceanic rifting. To this extent, we systematically tested two main parameters which control the timing of the evolution from initial oceanic extension to breakup and drifting, namely: a) different total extension rates between 4 mm/yr and 160 mm/yr, and b) different oceanic plate ages ranging between 10 Myr and 90 Myr, which act as proxies for the lithospheric thickness.Our results show that during oceanic rifting, the time required to achieve breakup of the extending oceanic lithosphere decreases logarithmically with an increasing extensional rate (i.e., the time needed to achieve breakup reaches a plateau). Our modelling also shows that lithospheric thickness plays a secondary, yet significant role in the type of oceanic rift that is formed (i.e., its structural configuration). This oceanic rift structure can comprise either a unique major graben or two main grabens, as preferable sites of extensional strain localization. Furthermore, when two main grabens develop, one of them often accommodates the bulk of the deformation, while the other wanes and eventually aborts. In this case, a more distributed pattern of extensional strain (comprising two main grabens) seemingly implies some delay in achieving full oceanic break-up, when compared with the single major graben scenario.Acknowledgements: numerical modelling was financed by Projeto GEMMA - PTDC/CTA-GEO/2083/2021, Fundação para a Ciência e Tecnologia. This work was funded by the Portuguese Fundação para a Ciência e a Tecnologia (FCT) I.P./MCTES through national funds (PIDDAC) – UIDB/50019/2020- IDL.
Ikaite (CaCO3*6H2O) -> ACC (amorphous calcium carbonate) -> calcite transformation and its paleoclimatological implication
Authors: Lázár Anett , Karlik Máté , Molnár Zsombor , Demény Attila , Németh Péter
Published: February 2023

Ikaite (CaCO3*6H2O) is a cryogenic calcium carbonate phase, which forms below about 5°C. If the temperature increases above 5-7 °C ikaite transforms to calcite. Understanding the transformation process is important to interpret paleoclimatological data from glendonites, i.e., calcite pseudomorphs after ikaite in sediments. Tollefsen et al. (2020) suggested that the transformation occurs via a coupled dissolution–reprecipitation mechanism at the ikaite–calcite interface (1). In contrast, Vickers et al. (2022) proposed a quasi-solid state ikaite to calcite transformation mechanismand suggested that stable isotope data of glendonite can be used for reconstructing paleotemperatures(2). However, in sediments the majority of the ikaite to calcite transformation occurs in diagenetic environments, where ambient solutions interact with the transforming mineral.We synthesized ikaite at 2 °C in alkaline environment in order to study its transformation using organic solvents, vacuum pumping and rapid (1 min) heating from 5 to 30 °C. These experiments indicated the formation of amorphous calcium carbonate (ACC) during the ikaite to calcite transition. We also monitored the ikaite transformation by letting the 2 °C parent solution to reach room temperature (25 °C) within ~5 hours. We observed ACC and calcite formations depending on the alkalinity of the parent solution. Our experiments suggest that the ikaite to calcite transition is a two-step process consisting of the solid-state ikaite → ACC transformation and the ACC → calcite dissolution–reprecipitation mechanisms. During these transitions ikaite lost all its water but preserved its original morphology. We hypothesize that the occurrence of a transient amorphous phase during the ikaite to calcite transition implies the alteration of the isotopic data, similar to what was reported for the ACC to calcite transition (3).We acknowledge the financial support of NKFIH ANN141894 grant. References:(1) E. Tollefsen, T. Balic-Zunic, C. M. Mörth, V. Brüchert, C. C. Lee and A. Skelton, Scientific Reports, 2020, 10, 8141.(2) M. L.Vickers, M. Vickers, R. E. M. Rickaby, H. Wu, S. M. Bernasconi, C. V. Ullmann, G. Bohrmann, R. F. Spielhagen, H. Kassens, B. P. Schultz, C. Alwmark, N. Thibault and C. Korte, Geochimica et Cosmochimica Acta, 2022, 334, 201-216.(3) A. Demény, Gy. Czuppon, Z. Kern, Sz. Leél-Őssy, A. Németh, M. Z. Szabó M. Tóth, C.-C. Wu, C.-C. Shen, M. Molnár, T. Németh, P. Németh and M. Óvári, Quaternary International, 2016, 415, 25-32.
Transparent exopolymer particles (TEP) in the tropical oligotrophic Atlantic Ocean: Sea-to-air transfer and atmospheric in situ formation
Authors: van Pinxteren Manuela , Robinson Tiera-Brandy , Zeppenfeld Sebastian , Wurl Oliver , Wex Heike , Engel Anja , Herrmann Hartmut
Published: February 2023

Transparent exopolymer particles (TEP) exhibit the properties of gels and are ubiquitously found in the world oceans. Here we demonstrate that TEP may enter the atmosphere as part of sea spray aerosol and likely influence cloud properties. We show number concentrations of TEP with a diameter > 4.5 µm, hence covering a part of the supermicron particle range measured in ambient aerosol and cloud water samples from the tropical Atlantic Ocean. Furthermore, TEP were analysed in generated aerosol particles using a plunging waterfall tank that was filled with the ambient seawater.Based on Na+ concentrations in seawater and the atmosphere, the enrichment of TEP in the tank generated aerosol particles was well in-line with another study. The TEP enrichments in the ambient atmosphere were, however, up to two orders of magnitude higher compared to the tank study and such high values are thus far not reported for supermicron aerosol particles. We propose that the high enrichment of TEP in the particles and in cloud water result from a combination of enrichment during bubble-bursting transfer from the ocean and secondary in-situ atmospheric formation. We suggest that similar (biotic and abiotic) formation mechanism reported for TEP formation in the (sea)water might take place in the atmosphere as well, as the required conditions (e.g. high concentrations of dissolved TEP precursors such as polysaccharides, presence of bacteria in the cloud water) were given.TEP concentrations in the atmosphere were two orders of magnitude higher than INP concentrations in the aerosol particles and cloud water, respectively. However, only a part of the TEP population, assumingly the one colonized by bacteria, might contribute to INP population, and are worth further studies.The study contributes to the international SOLAS program.Ref. : van Pinxteren, M., Robinson, T.-B., Zeppenfeld, S., Gong, X., Bahlmann, E., Fomba, K. W., Triesch, N., Stratmann, F., Wurl, O., Engel, A., Wex, H., and Herrmann, H.: High number concentrations of transparent exopolymer particles in ambient aerosol particles and cloud water – a case study at the tropical Atlantic Ocean, Atmos. Chem. Phys., 22, 5725–5742, https://doi.org/10.5194/acp-22-5725-2022, 2022. 
Contemporary publications in Europe on the Spanish earthquake of 1884
Authors: Buforn Elisa , Udías Agustín , Mattesini Maurizio
Published: February 2023

On 25th December 1884, a damaging earthquake shocked the Granada-Malaga (Spain) region, followed by a large number of aftershocks. This is the largest earthquake (Imax= IX-X, EMS-98, estimated magnitude 6.7) in southern Spain, with 750 persons killed and 1500 injured, and 4400 houses destroyed. After the occurrence of the main shock, a considerable number of reports on the damage caused by the catastrophic Andalusian earthquake were published mainly during the following year (1885) in several European journals, as well as in bulletins of scientific societies and books. A few of them were anonymous notes while others were signed by the most important geologists and seismologists from different European countries. Exceptional cases are the publications from the members of the three commissions (Spanish, French and Italian) that were specifically appointed to study this Andalusian earthquake, with the participation of prestigious seismologists, such as Macpherson, Mercalli, Taramelli, Fouqué, and Barrois. We present detailed information about the publications that appeared mainly during the following year (1885) of the occurrence of this earthquake. The prompt study of the Andalusian earthquake provided an opportunity for the scientific community at that time to present and disseminate new modern ideas about the nature of earthquakes and their relationship with the geodynamic processes and geology of the region abandoning the traditional explosive source.
Experimental precipitation of cryogenic calcite and vaterite
Authors: Uwakwe Ozioma Carol , Riechelmann Sylvia , Hoffmann René , Spötl Christoph , Jantschke Anne , Immenhauser Adrian
Published: February 2023

Cryogenic cave carbonates (CCCs) are speleothems precipitated from freezing water bodies in caves. A series of scholarly papers have explored natural CCC precipitation kinetics, crystal habit, mineralogy, crystallography and geochemistry. However, cave depositional environments are complex multi-parameter systems, and the inherent difficulty of unravelling the physicochemical parameters of ancient speleothem formation also applies to CCCs. In order to test previous models and concepts, experiments were conducted by cooling calcium-rich bicarbonate water under controlled laboratory conditions. The experiments involved calcite precipitation at different durations (6 to 91 days) and temperatures (1, +0, -0.5, -0.7, -1 and -2 °C). The results show that subtle changes in temperature and calcite saturation index (SIcc) remarkably affect the CCC morphological variability and mineralogy. Rhombohedral calcite crystals precipitated both in experiments with and without ice. In contrast, spherulitic crystals (vaterite) precipitated from near-completely frozen waters with high calcite saturation indices. Experimental water monitoring revealed increased calcite precipitation followed by decreased water conductivity values. The formation of CCCs is accompanied by non-equilibrium reaction kinetics, which tends to enrich the isotopic composition of the parental water. Longer experimental durations lead to increasing CO2 degassing and 13C enrichment of the water. Data from the first experimental work dealing with cryogenic carbonate precipitation and isotope geochemistry, as documented here, shed light on the origin of these peculiar speleothems and provides constraints to interpret morphologies and isotopic compositions of ancient CCCs. 
An Isentropic Mass Circulation View on the Extreme Cold Events in the 2020/21 Winter
Authors: Yu Yueyue
Published: February 2023

Three extreme cold events successively occurred across East Asia and North America in the 2020/21 winter. This study investigates the underlying mechanisms of these record-breaking persistent cold events from the isentropic mass circulation (IMC) perspective. Results show that the midlatitude cold surface temperature anomalies always co-occurred with the high-latitude warm anomalies, and this was closely related to the strengthening of the low-level equatorward cold air branch of the IMC, particularly along the climatological cold air routes over East Asia and North America. Specifically, the two cold surges over East Asia in early winter were results of intensification of cold air transport there, influenced by the Arctic sea ice loss in autumn. The weakened cold air transport over North America associated with warmer northeastern Pacific sea surface temperatures (SSTs) explained the concurrent anomalous warmth there. This enhanced a wavenumber-1 pattern and upward wave propagation, inducing a simultaneous and long-lasting stronger poleward warm air branch (WB) of the IMC in the stratosphere and hence a displacement-type Stratospheric Sudden Warming (SSW) event on 4 January. The WB-induced increase in the air mass transported into the polar stratosphere was followed by intensification of the equatorward cold branch, hence promoting the occurrence of two extreme cold events respectively over East Asia in the beginning of January and over North America in February. Results do not yield a robust direct linkage from La Niña to the SSW event, IMC changes, and cold events, though the extratropical warm SSTs are found to contribute to the February cold surge in North America.
The North-South variation and mechanism of the precipitation over the Tibetan Plateau during the monsoon in the past 60 years
Authors: Wang Hao , Hu Zeyong
Published: February 2023

Tibet plateau plays very crucial roles in globle climate system, and the precipitation is  one of the main factors in Tibet plateau climate system, Based on GPCC monthly precipitation data and ERA5 monthly precipitation reanalysis data from 1961 to 2016, this study analyzes the spatio-temporal distribution and evolution of plateau precipitation during the May-September monsoon period under the background of global warming. Try to analyze the mechanism reason affecting precipitation variation in different regions. The precipitation in the South part of Tibet plateau began to increase in May, and advance to the northwest part of Tibet plateau during the July and August, and began to back to the south in September. According to The decomposition of the empirical orthogonal function (EOF), we divided the Tibet plateau into north and south two parts by the mount tunggula, on the interannual variability, percentage of precipitation in the monsoon plateau exists reverse change relation, precipitation showed a trend of slight decrease in the south part of plateau, plateau in northern precipitation shows ascendant trend on decadal scale, rate of precipitation in the plateau there are shocks between 3 to 5 years in 7-9 or 11 years. There is a north-south inverse change rate in the precipitation in the plateau during the monsoon period. The analysis of the relationship between the monthly precipitation data and the atmospheric circulation in the south and north of the Plateau shows that the precipitation in the south of the Plateau is affected by the South Asian monsoon, while the precipitation in the north of the plateau is related to the Rossby wave of the subtropical westerly jet. In other words, the precipitation in the southern part of the plateau is mainly controlled by summer risk, while the precipitation in the northern part of the plateau is affected by subtropical westerly winds. Keyword: Tibetan Plateau，Precipitation，Circulation，South asia monsoon，Jet stream
"Measurements and models of GHGs and short-lived pollutants in the Baltimore/Washington area: Emissions and environmental justice"
Authors: Dickerson Russell , Ren Xinrong , Karion Anna
Published: February 2023

Abstract: Greenhouse gases and associated pollutants (CO, NOx, VOCs, aerosols) are measured from a small airplane, mobile laboratory, and towers.  Through mass balance calculations and comparison to numerical models such as CMAQ-GHG  we estimate the total flux from the cities of Baltimore, MD and Washington, DC.  Emissions inventories were found to underestimate methane emissions substantially and have been improved.  Major sources include leakage in the natural gas delivery system and biogenic processes including landfills.  Measurements with high spatial and temporal resolution reveal hot spots of high concentrations often associated with pollutants such as black carbon (BC) and NO2 that pose a health hazard in disadvantaged communities. 
Storylines of the impacts in the Netherlands of alternative realizations of the Western Europe July 2021 floods
Authors: Van Den Hurk Bart , de Bruijn Karin , Slager Kymo , Hegnauer mark , Rongen Guus
Published: February 2023

The 2021 summer flooding was an extremely rare event, driven by precipitation extremes that exceed Dutch design levels for flood protection in regions away from the main rivers and coastline. However, similar events in neighboring locations cannot be ruled out even in the near future. The implications of such extreme rainfall amounts will vary by region, subject to local topography, hydraulic flow patterns, water management, and societal exposure. We explore the geographic distribution of potential flood impacts induced by a similar event by constructing impact-oriented event storylines for different subregions in the Netherlands. The plausibility of the storylines is underlined by using physical evidence, proven impact-modelling concepts, and expert judgment successfully assessing the (sometimes unexpected) outcomes. The approach supports impact assessment for extraordinary events.The presentation will illustrate the development of the storylines, and its uptake and interpretation by governing authorities responsible for water safety, civil protection and water management.