bluuebunny/crossref_metadata_2025 huggingface dataset:
How would shifting manufacturing from China to Indonesia or India impact human health and social economy?
Authors: Ran Qi , Lee Shao-Yi , Zheng Duofan , Chen Han , Yang Shili , Moore John , Dong Wenjie
Published: February 2023

The COVID-19 pandemic is reshaping the global trade and supply chains, and some developed countries may consider relocating strategic manufacturing operations out of China, providing new opportunities for some South and Southeast Asian countries. Since the shift of manufacturing is accompanied by redistribution of emission sources of air pollutants, the impacts on environment and human health of the countries directly involved and their neighbors, should be considered. We used the Community Earth System Model, the Integrated Exposure-Response (IER) model and Willingness To Pay (WTP) method, to simulate fine particulate matter (PM2.5) and the socio-economic responses to shifting manufacturing from China to Indonesia or India. Our results show that significant effects on PM2.5 related mortality and economic cost for these deaths were seen in many East, Southeast and South Asian countries, particularly those immediately downwind of these three countries. Transferring all of export-related manufacturing to Indonesia resulted in significant mortality decreases in China and South Korea by around 78k (5 per 100k) and 1k (2 per 100k) respectively, while Indonesia’s mortality significantly increased (73.7k; 29 per 100k), as well as India, Pakistan and Nepal. When manufacturing was transferred to India, mortality rates in East Asia show similar responses to the Indonesian scenario, while mortalities in India increased dramatically by 87.9k (6 per 100k), and mortalities in many neighbors of India also severely increased. Shifting manufacturing to India in our simulations led to more Asian countries showing significant changes in PM2.5 related deaths and economic costs than an equivalent shift to Indonesia. This is because of the maritime Indonesian setting as well as patterns of surface winds. Nevertheless, the economic costs for these deaths were much smaller than national GDP changes in China (0.9% of GDP vs. 18.3% of GDP), India (2.7% of GDP vs. 84.3% of GDP) or Indonesia (9.4% of GDP vs. 337% of GDP) due to shifting all of export-related production lines from China to India or Indonesia. Perhaps the most concerning aspect of this study is the damage to “innocent” victims of any manufacturing shifts in third countries that do not see any domestic economic gains. Morally, part of the benefits of economic activity should be used to compensate the neighboring communities where mortality increases occur.
Runoff parameterization for global scale hydrology based on a variably saturated flow model
Authors: Miura Yosuke , Yoshimura Kei
Published: February 2023

Groundwater is the world's essential water resource, and groundwater flow is strongly linked with surface water. In some cases, groundwater can even affect precipitation through evapotranspiration. In the current Earth System Model (ESM), a fixed and constant one-dimensional vertical grid is used in the unsaturated zone. The thickness of the unsaturated zone is expected to differ in a given region under a future climate. Therefore, the representation of groundwater flow in the ESM may be insufficient. In particular, on steep slopes such as mountainous areas, it is considered that there are limitations to the runoff process. In this study, we developed a three-dimensional variably saturated flow model that was parameterized for the runoff process and validated in the mountainous area.In mountainous areas where topographic terrain is severe, calculations at hundreds to tens of meters are necessary to better performance for groundwater flow. However, it is unrealistic to calculate the groundwater dynamics at that scale over global lands. Therefore, it is necessary to calculate on a coarse grid with parameterization. We developed the runoff parameterization using a 1-minute grid with topographic information within the grid. The parameterization validation was performed for the whole of Japan, which has a large elevation distribution. A part of the results of the land surface model, MATSIRO, was passed to the developed model to calculate runoff. The calculated runoff was input into the river routine model, CaMa-Flood, and compared to observed river discharge. As a result, the reproducibility of the river discharge was improved compared to the case without the parameterization and the MATSIRO’s results.
Importance of trans-crustal geological processes in understanding the genesis of giant epithermal gold deposits: The case of Hishikari deposit, Japan
Authors: Ishida Mizuki , Nakamura Kentaro , Iwamori Hikaru , Hosono Takahiro , Kato Yasuhiro
Published: February 2023

Epithermal deposits are formed in shallow (< 1 km) crustal environments by precipitation of ore minerals from hydrothermal fluids, associated with magmatic activities. Epithermal deposits are important sources of gold and associated critical metals (e.g., Ag, Bi, Te) used in high-tech industry (e.g., [1]). However, little is known about the controls on their deposit sizes, which range more than two orders of magnitude (<1 to >100 t of contained Au). Since deposit size is a major determining parameter for mine profitability, estimating the governing processes for metal endowment should have important implications for exploration. Here we show that the giant (> 200 t Au) Hishikari epithermal gold deposit in south Kyushu, Japan, is likely to have formed by combination of the following three trans-crustal geological processes: (i) oxidized source mantle of primary magmas, (ii) differentiation of ore-forming magmas without voluminous sulfide saturation and (iii) structural focusing of exsolved ore-forming fluids. These geological processes were recognized by (i) high V/Yb ratio (> 160) of high MgO regional volcanic rocks which reflect the oxidizing [2], high sulfur and gold solubility condition during mantle melting, (ii) minor contribution from reducing crustal rocks [3] and late magnetite saturation which maintained a relatively high fO2 as well as high sulfur solubility until later stage of differentiation, and (iii) basement uplift or depression detected by geophysical surveys [4] which created effective conduits for hydrothermal fluids. In contrast, representative districts in Japan with previous extensive exploration campaigns (Toyoha, Nansatsu, Iriki, Masaki) failed to meet more than one of the above criteria, which likely explain the smaller or lack of gold mineralization in these districts. Our findings demonstrate the importance of optimally aligned trans-crustal geological processes in the formation of giant gold deposits and the potential utility of the geochemistry of regional volcanic rocks in early stages of epithermal gold exploration.[1] Goldfarb, R. J., et al. (2016). Reviews in Economic Geology 18: 217-244.[2] Laubier, M., et al. (2014). Earth and Planetary Science Letters 392: 265-278.[3] Hosono, T., et al. (2003). Chemical Geology 201: 19-36.[4] Izawa, E., et al. (1990). Journal of Geochemical Exploration 36: 1-56. 
Coupled feedback between the tropics and subtropics of the Indian Ocean with emphasis on the coupled interaction between IOD and SIOD
Authors: Sebastian Anila , Gnanaseelan Chellappan
Published: February 2023

Indian Ocean Dipole (IOD) is an air-sea coupled variability in the Tropical Indian Ocean (TIO), which strongly impacts climate variability over the Indian Ocean rim countries. Though many positive IODs co-occurred with El Niño Southern Oscillation (ENSO), IODs do evolve independently, suggesting the possible role of internal dynamics of the Indian Ocean. In this study, the subtropical IOD (SIOD) is reported as one of the triggers for non-ENSO IODs. The study highlights the existence of cyclic feedback between IOD and SIOD through tropical subtropical interaction, a possible mechanism for the biennial tendency of both IOD and SIOD modes. The positive SIOD induce warming in the southwest of the Subtropical South Indian Ocean (SSIO) during April-May months and creates a meridional cell with subsidence over the southwestern TIO region (10oS). The subsidence expands the existing anticyclonic circulation over SSIO towards the equator and develops easterlies along the equator, warming the western TIO region. A zonal-vertical cell with convection over the western TIO and subsidence over the eastern TIO originates during June-July, which subsequently generates positive IOD in the following months. The positive IOD triggers negative SIOD by developing a stationary Rossby wave train in the midlatitudes. The southeastern anticyclonic circulation develops during the IOD peak season as Gill’s response initiates warm SST anomalies in the northeastern subtropics. As a result of the warming, the evolution of upper-level divergence and high absolute vorticity gradient over the subtropics generate an equivalent barotropic Rossby wave number 3 pattern in the extratropics. The cyclonic circulation over the southwest SSIO related to this Rossby wave pattern creates cold SST anomalies there. The cooling in the southwest and the warming in the northeast SSIO persisted from the IOD peak season, which strengthened the cyclonic circulation over SSIO, reinforcing the existing negative and positive SST anomalies through a positive feedback mechanism and generating negative SIOD, which peaks in the following January-March months.
Kinematics of scarp retreat in idealized tilted channel experiments
Authors: Hung Yi-Fan , Capart Hervé , Stark Colin P.
Published: February 2023

In some landslides, collapse is accompanied by the upslope retreat of a well-defined scarp whose speed controls the rate of mobilization of debris. Here we examine the evolution of such scarps in an idealized laboratory setting. We conduct tilted channel experiments involving retrogressive dry granular landslides over an erodible substrate. After first tilting up a deep sand layer to close to the angle of repose, then imposing an abrupt base-level drop, granular flow is induced at the downstream outlet. This flow generates an upstream-traveling wave with a well-defined scarp at the upstream tip. Downstream of the moving scarp, sand flows as an avalanching layer of finite depth over the erodible but stationary substrate, and outflows over the lowered outlet sill. A series of such experiments were conducted to determine the influence of channel width and base-level drop height on the speed of scarp retreat and other flow properties. Measurements included the time-evolving profile of the free surface, surface velocities acquired using particle tracking velocimetry, and the time-evolving mass outflow rate at the downstream outlet. Dimensional analysis clarifies the physical mechanisms governing the rate of scarp retreat. These results will help guide and validate numerical models of granular landsliding over erodible substrates.
Types of the evolution and dynamics of marine heatwaves in the East Sea (Japan Sea)
Authors: Jayanthi Sasikumar Saranya , Nam SungHyun
Published: February 2023

Extreme oceanic conditions known as marine heatwaves (MHWs) are characterized by high seawater temperature (beyond the 90th percentile threshold) that has a negative impact on marine ecosystems and humanity. The East Sea (Japan Sea), a semi-enclosed deep basin connected to the outside seas/ocean by shallow and narrow straits, has recently experienced the most rapid upper ocean warming in the world seas. Characteristics and evolution of MHWs in the East Sea, including their subsurface evolution, need to be better understood as still poorly understood in spite of recent reports on their increasing frequency and severity. Here, the sea’s MHWs retrieved from ocean reanalysis/model data (Simple Ocean Data Assimilation (SODA), HYbrid Coordinate Ocean Model (HYCOM), Global Ocean Reanalysis product (GLORYS) and Estimating the Circulation and Climate of the Ocean (ECCOVr4)) were initially compared to those from a long-term (from 2000 to 2014) time-series observations conducted near the east coast of Korea using a surface mooring named the East Sea Real-Time Ocean Buoy (ESROB). Then, a rising frequency of annual mean and summer (JJA) MHWs from 1982 to 2019 throughout the entire East Sea was characterized using the SODA, HYCOM, GLORYS, and ECCOVr4, yielding a maximum increasing rate of 0.45 occurrences per decade. Using unsupervised machine learning clustering techniques (K-mean and Hierarchical), three different types of MHW evolutions were identified — subsurface to surface evolution (Type-A), surface evolution (Type-B), and surface to subsurface evolution (Type-C) in six sub-regions — three in the west and three in the east. This study discusses possible explanations for these types of MHW evolution in the selected sub-regions of the sea, providing better understanding of surface and subsurface MHWs in the most rapidly warming marginal sea.
Developing Tailored Agro-met Predictions for Target Cropping Systems in Vanuatu: tailOred System of Climate services for AgRiculutre (OSCAR)
Authors: Chun Jong Ahn , Park Sugyeong , Jung Imgook , Lee Seongkyu , Park Kyungwon
Published: February 2023

Vanuatu as one of Small Island Developing States (SIDS) in the Pacific region is one of the most vulnerable countries to climate impacts including climate-related natural disasters. In order to build the adaptive capacity of vulnerable communities and users of climate information and services. The Climate Information Services for Resilient Development Planning in Vanuatu (Van-CISRDP; Vanuatu Klaemet Infomesen blong Redy, Adapt mo Protekt (Van-KIRAP) in Bislama) project was approved at the Green Climate Fund (GCF) 15th meeting of the board in Apia, Samoa in December 2016 (FP 035). The two implementing entities: Secretariat of the Pacific Environment Program (SPREP) and Geo-Hazard Department (VMGD) and three delivery partners:  APEC Climate Center (APCC), Commonwealth Scientific and Industrial Research Organization (CSIRO) and Australia Bureau of Meteorology are collaboratively conducted the Van-KIRAP project. In the Van-KIRAP project, the major activities of APCC consist of (1) Develop Agro met information portal including new on line IT infrastructure and software (OSCAR prototype), (2) Collecting, modelling, analysis and reporting of agro-met data to determine optimal agriculture crop planning options, (3) Undertaking field trials and validation prior to incorporation into DSS delivery platforms, ground truthing and outreach with target Next/End Users, and (4) Develop the crop-climate diary (CCD) customised for agro-met data collection. In this presentation, we will introduce the APCC portion of the Van-KIRAP project including experimental field trials for major staple crops, various training and education programs in both on-line and on-site, and the development of the OSCAR system incorporating various Artificial Intelligence techniques and modelling approaches. These will provide relevant climate information applied to the agriculture sector. The CCD will serve as a tool to collect data in an efficient streamlined manner from different areas of Vanuatu. Utilizing the data from CCD, OSCAR will be a hub for the interaction of climate information and agriculture.
A critique review and update of the earthquake surface fault rupture hazard in the northern zone of Tehran metropolis, Iran
Authors: Ehteshami-Moinabadi Mohsen , Nasiri Shahram
Published: February 2023

Abstract The megacity of Tehran, the capital of Iran, is located on the southern slope of the central part of the Alborz Mountain range. The earthquake risk assessment studies in the Tehran metropolis have been focused mainly on earthquake data and technical aspects of buildings and structures. In the meantime, the data on the fault that can cause earthquakes and the related triggered fracture system, like the potential of direct surface rupture that can be developed or occur as the result of an earthquake faulting, have not been significantly updated during the last two decades for mountain front foothills. The land use changes and the growth of the metropolis of Tehran during the last two decades, especially in the city's northern half, with the lack of any regulatory action on the fault zone, are escalating the risk of surface rupture. In this regard, the need to update the fault map and establish a fault zone regulatory act is paramount to importance. By reviewing the existing information and combining it with new satellite data, an updated map of the faults in the northern zone of Tehran city has been presented. The vital point in this map is to recognize the continuation of the fault trends that were introduced before, but their end was unknown. Also, a vast network of fractures or subsidiary faults belonging to the North Tehran fault system has been mapped, especially in its hanging wall part, which has not been published before. The result of the overlapping faults with urban structures and building areas shows that in the lack of regulation, the fault zone's ignoring continues in the new constructions of the Tehran metropolis. It is estimated that more than twenty hospitals, many of which are newly built, along with other strategic and sensitive structures, are in danger of surface rupture, and it is indispensable to think of a solution for them.Additionally, many important buildings are in danger of fault rupture. We recently found that large ancient mega-landslides exist in the northern foothills of Tehran that are under more investigation. In the end, this research emphasizes the special attention to the lateral investigation of thrusts located in the north of Tehran between the North Tehran fault and the Masha fault, especially the Imamzadeh Dawood, Kigah and Pourkan faults.Keywords: fault surface rupture, fault setback, earthquake, seismic hazard, Tehran, North Tehran Fault
Constrained Emergence of Air Temperature Change Signal in Northern-Central India From Background Variations
Authors: Zhang Kaiwen , Zuo Zhiyan , Zhang Renhe , Xiao Dong , Qiao Liang
Published: February 2023

The signal of temperature change has emerged from background variations in most tropical regions in boreal summer over decadal-centennial timescales but not in northern-central India (NCI). In this study, we investigated the reason for the limited temperature change in NCI. We found that internal variability, largely caused by the Interdecadal Pacific Oscillation (IPO) on a ∼20-year timescale, has the potential to mask the temperature change signal. Besides, local response to external forcing, linked to non-greenhouse gas (GHG) forcings, strongly overrides GHG warming in NCI, which results in little trend in the temporal evolution of external variability. The internal variability related to IPO and the limited warming arising from the competition between multiple forcings result in the smallest signal-to-noise ratio and thus, the temperature change signal fails to emerge from the background variations.
Interpretable Deep Learning for the Identification of Sudden Stratospheric Warming Events
Authors: Zeng Yi-Jhen , Liang Yu-Chiao
Published: February 2023

An advanced understanding of stratospheric variability and its coupling to the troposphere is critical to improving the prediction of near-surface fields at subseasonal-to-seasonal timescale. In the most extreme case, a stratospheric sudden warming (SSW) event occurs and substantially perturbs the stratospheric circulation and, subsequently, exerts profound surface impacts. Interpretable deep learning could be a powerful tool in recognizing SSW spatial details and better categorizing the type of disrupted vortices. Here we apply a deep learning approach to identify SSW events from nonSSW ones using a global climate model with large ensembles. We start with a 1-dimensional case by using the stratospheric zonal wind of SSW events along the 60°N latitude to train neural networks with different complexity: logistic regression network, shallow neural network, and deep neural network. All neural networks can identify SSW events with a fairly high accuracy. To address the interpretability of how these neural networks learn to distinguish SSW from nonSSW events, we mask out the zonal wind fields with varying longitudinal windows to test if the spatial structure of disrupted vortices is decisive for the network performance. Neither shallow nor deep neural networks show apparent spatial dependence when the masking window is short, while logistic regression network gives strong spatial dependence centering around 160°W, where small variation and negative mean value of zonal wind appear. The dependence of shallow and deep networks emerges as the window length increases. To further explore the 2-dimensional spatial dependence, we further train a convolutional neural network exploiting the two-dimensional zonal wind fields in the Northern Hemisphere. Similar tests are performed by systematically masking out the zonal wind fields by a rectangular region with varying size. The spatial dependence of 2-dimensional neural network is largely consistent with 1-dimensional networks, but the spatial extents expand wider to the north of south of 60°N. The results highlight the capability of interpretable deep learning tools in learning the SSW spatial information and revealing the spatial dependence, which may carry out important implications for the prediction of SSW genesis.Key words: interpretable deep learning, stratospheric sudden warming
Exploring the potential of machine learning for leaf angle distribution estimation from leveled digital photography
Authors: Aun Margit , Pisek Jan
Published: February 2023

Leaf angle distribution (LAD) is an important plant structural trait that determines radiation interception, biomass production, rainfall interception, and evapotranspiration. Assessment of LAD is a challenging task and a significant source of uncertainty in ecological models. So far, the information on leaf inclination angle distributions of different plant species is scarce in literature and databases (e.g. TRY). Approximate quantification of LAD is often made by means of modeling.The aim of this study is to find a user-friendly and accessible method to estimate leaf angle distribution type. We used Google’s TensorFlow convolutional neural network (CNN) to test for the first time the possibility of using machine learning for automatically classifying LAD types from leveled digital photographs. We used different combinations of five LAD distribution types (planophile, erectophile, spherical, plagiophile and uniform). The highest training accuracy of 95% and validation accuracy of 91% were achieved by using the two most distinct leaf angle distribution types – planophile and erectophile. As expected, the accuracy subsequently decreased with the addition of other leaf angle distribution types (spherical, plagiophile, uniform). However, our results indicate that the involvement of machine learning may indeed hold the potential to remove the current bottleneck in retrieving the information on leaf angle distribution and its better quantification in ecosystem modeling.
Impact assessment of seawater intrusion on shallow coastal groundwater in eastern Saudi Arabia using a multidisciplinary approach
Authors: Benaafi Mohammed , Abba Sani , Aljundi Isam
Published: February 2023

Seawater intrusion is considered the main threat to fresh groundwater resources in coastal regions, especially in arid areas such as Saudi Arabia. For decades, the coastal community in the eastern province of Saudi Arabia has depended on groundwater for domestic and agricultural uses. The current study objective is to assess the degree of seawater intrusion and its impact on the shallow groundwater in the eastern coastal region of Saudi Arabia. We integrated three techniques, including hydrogeology, hydrochemistry, and electrical resistivity. A hydrogeological and electrical resistivity field survey was conducted, coupled with in situ measurement of the shallow groundwater's hydrochemical properties (pH, ORP, DO, EC, temperature, and turbidity). This was followed by collecting 24 water samples for the laboratory analysis of hydrochemical properties (major cation and anion). Geospatial maps of salinity (electrical conductivity (EC)) and chloride were established to trace their concentrations from the sea landward. The hydrochemical spatial maps were correlated with the geoelectrical measurements to delineate the lateral and vertical extent of seawater intrusion in the studied shallow coastal aquifer. The hydrochemical results show that chloride and sodium are the dominant ions, indicating seawater intrusion is the source of elevated salinity. The salinity (EC) and chloride concentrations of the tested GW range from 6452 μS/cm to 44420 μS/cm, and 1041 mg/L to 8523 mg/L, respectively. The study results indicate that the shallow groundwater has been contaminated with seawater up to around 4 km landward, with a maximum depth of 30 m. The main conclusion of the current study is that decades of overexploitation of groundwater aquifers in the studied region have resulted in salinity contamination of shallow groundwater by seawater intrusion to levels of saline and brackish water. The result of this study may help the decision-maker implement a proper management measure to safeguard groundwater resources for coastal communities and develop a plan to remediate the shallow groundwater aquifer through desalination and reinjection for the environment and ecosystem benefits.
Occurrence characteristics of lacustrine shale oil in the second member of the Kongdian Formation in the Cangdong Sag, Bohai Bay Basin, China
Authors: Dong Qingmin , Chen Shiyue
Published: February 2023

The second member of the Kongdian Formation (Ek2) in the Cangdong Sag has become an important field of shale oil exploration in the Bohai Bay Basin. To investigate the occurrence characteristics and discuss the controlling factors of shale oil mobility in the Ek2, the research presented in this study is based on core and thin section observations, XRD analysis, total organic carbon (TOC), Rock-Eval pyrolysis, multiple isothermal stages (MIS) pyrolysis, low-temperature nitrogen physisorption (LNP), mercury intrusion porosimetry (MIP), and scanning electron microscopy (SEM). The results show that the Ek2 shales can be classified into five types of lithofacies, including laminated felsic shales, laminated mixed shales, massive mixed shales, laminated carbonate shales, and massive carbonate shales. The shales were characterized by high organic matter abundance and moderate thermal evolution with good to excellent hydrocarbon generation potential and contained a high abundance of Type I and II1 kerogens. Laminated felsic shales and laminated mixed shales had obvious advantages in the thermally extractable hydrocarbon content (S1) value, oil saturation index (OSI) value, free oil, and movable oil content with other lithofacies. Analysis of LNP, MIP, and MIS pyrolysis show that the residual shale oil mainly occurred in the pores with diameters smaller than 200 nm, and the occurrence pore diameters of residual oil in some laminated shale samples could reach 50 μm. The lower limits of the occurrence pore diameter of free oil and movable oil were 7 nm and 30 nm, respectively. The mobility of shale oil is controlled by the shale oil component, thermal maturity, TOC content, and pore volume.
Environmental responses of gross primary production: emerging knowledge gaps
Authors: Bloomfield Keith , Stocker Benjamin , Keenan Trevor , Prentice Colin
Published: February 2023

Accurate simulations of gross primary production (GPP) are vital in our efforts to model the global carbon cycle.  The instantaneous controls of leaf-level photosynthesis, which can be studied in manipulative experiments, are well established; but there is no consensus on how canopy-level GPP depends on spatial and temporal variation in the environment.  Models make a variety of assumptions when ‘scaling-up’ the standard model of photosynthesis. These assumptions are consequential, leading to large differences in the apparent environmental dependencies of modelled GPP.We have attempted to understand and resolve these inconsistencies using both theoretical analysis of the processes involved in scaling-up from photosynthesis to GPP, and empirical analysis by generalized linear modelling of GPP inferred from eddy-covariance flux measurements.  Theoretical analysis has explained why ‘light-use efficiency’ (LUE) models work – and has led to the ‘P model’, a notably parsimonious model that coordinates capacities for CO2 fixation, water- and electron-transport to simulate GPP. For empirical analysis we used eddy-covariance data from over 100 sites worldwide.  We combined these flux data with in situ radiation measurements and the MODIS FPAR product.  Soil moisture data were estimated using the SPLASH model, with appropriate meteorological inputs, and soil water-holding capacity derived using SoilGrids.In arriving at a preferred statistical model, we showed that daytime air temperature and vapour pressure deficit, and soil moisture content are salient predictors of LUE. Despite taking LUE (GPP normalised for absorbed light) as our response variable, we found that the diffuse fraction of solar radiation has a strong influence on production: second only to VPD in predictive power.  That finding challenges the idea, dating back 50 years to studies of crop yield, that time-averaged carbon assimilation is simply proportional to the amount of absorbed light. Our empirical analysis of GPP data has led us to seek ways to improve the performance of the P model without sacrificing its simplicity and transparency. Differential canopy penetration by diffuse and direct radiation is one line of development. Also needed is an improved representation of the temperature dependency of GPP. The empirical analysis suggested a generally increasing (asymptotic) trend over the observed range in growth temperature rather than the temperature optimum of 15°C displayed by the current P model simulations.Our analysis suggests it is feasible to predict GPP using a single model structure, common across vegetation categories.  But the goal of a model design that is at once simple, theoretically well-founded and robust continues to generate scientific challenges.
Recovery of critital raw materials from mining wastes: challenges, opportunities and barriers.
Authors: Ruiz Cánovas Carlos , Nieto Jose Miguel , Olias Manuel , Macias Francisco , Basallote Maria Dolores , León Rafael , Romero Jonatan , Pérez-López Rafael
Published: February 2023

Mining is a critical activity aimed at providing commodities for economic developing. However, the generation of wastes in the vicinity of the mines may lead to severe environmental problems and human health risks. Therefore, mining companies have to face huge investments in remediation options. This situation is especially challenging in historical mine sites, which accumulate large amounts of metal-rich wastes without any environmental regulation [1]. However, these wastes could be a source of critical raw materials due to the high concentrations observed for some elements. This is especially important in those countries with absence of primary deposits, which suffer from a strong external dependence for supply. The recovery of these critical raw materials could constitute a great opportunity to satisfy the internal demand and at the same time help to offset expensive waste treatment costs. However, the effective recovery of these valuable elements requires a vast amount of previous work such as site-by-site studies to determine the potential metal grade in wastes and deep investigation of mineralogical siting of valuable metals in these wastes or selective recovery methods. In this sense, there are some social, economic and technological barriers that must be overcome to achieve the final recovery. In this sense, the use of waste materials has commonly met resistance in the industrial sector and only being accepted after proved experience is achieved. On the other hand, the application of technologies may face technical and economic barriers such as the non-selectivity of extraction and recovery methods developed and the high initial costs which put in risk the return on investment and the cost efficiency of the recovery scheme [2]. Therefore, deep case-by-case investigation is required to achieve cost-effective secondary source of critical raw materials from wastes. [1] Cánovas, C.R., Macías, F., Basallote, M.D., Olías, M., Nieto, J.M., Pérez-López, R., 2021. Metal(loid) release from sulfide-rich wastes to the environment: the case of the Iberian Pyrite Belt (SW Spain). Current Opinion in Environmental Science & Health 20, 100240. https://doi.org/10.1016/j.coesh.2021.100240.   [2] Cánovas, C.R., Macías, F., Pérez-López, R., Basallote, M.D., Millán-Becerro, R., 2018. Valorization of wastes from the fertilizer industry: Current status and future trends. J. Clean. Prod. 174, 678e690. https://doi.org/10.1016/j.jclepro.2017.10.293.
Meteor infrasound recordings at a dense seismic broadband transect in Spain
Authors: Stich Daniel , Casado Rabasco Josué , Madiedo José María , Guerrero Rascado Juan Luis , Morales Jose
Published: February 2023

With the densification of seismic networks, recordings of atmospheric infrasound events through ground coupled signals are becoming more numerous. In particular, there’s an increasing probability of detecting direct arrivals at near distances from the source. Here, we analyze a meteor event with absolute magnitude m = −17 on December 11th 2016 that was recorded coincidentally along a dense seismic broadband transect near Granada, Spain. Using 44 near-field detections and the ERA5 atmospheric temperature and wind speed model, we can locate the acoustic source at 38 km height, consistent with the triangulation of the meteor terminal explosion from camera recordings.The waveforms recorded along the seismic transect reveal important differences between nearby stations, emphasizing the importance of local conditions for acoustic wave propagation and acousto-seismic coupling. A common component of all waveforms are ~0.5 s long N-waves, inherited from the atmospheric shock wave, however waveform attributes such as peak velocity amplitudes and frequencies, signal duration and signal energy show variations of one order of magnitude. Also, the three-component signal polarization shows large variability among stations, suggesting that waveform complexity and the repetitions of N-waves reflects the interaction with local topography, in addition to multipathing through the small-scale structure of the atmosphere along the path. Our observations shed light on various causes of complexity in the conversion of the free-atmosphere acoustic wavefield to ground motion, and point to the difficulties involved in estimating the original pressure signal from acousto-seismic data.
Discrete element modelling of grain-scale aeolian sediment transport on moist beach surface
Authors: Wang Xiuqi , Campmans Geert , Weinhart Thomas , Thornton Anthony , Luding Stefan , Wijnberg Kathelijne
Published: February 2023

In coastal areas, aeolian sediment transport could show significant spatio-temporal variability as a result of varying beach surface properties. The observed morphological patterns also vary with surface conditions. Surface moisture is one of the most important factors limiting the sediment transport process [1]. Moisture between the sand grains can influence both the mechanism of aerodynamic entrainment and the momentum transfer upon the collision between a saltating particle and the bed. Next to those, the saltation features are likely to be different from those in dry cases, hence different subsequent bed form patterns [2].To understand the intrinsic variability of large-scale sediment transport on moist beach and the features of morphological processes, it is necessary to quantify the sediment transport properties on the grain scale first. From the information on the grain-scale dynamic behaviour, the up-scaling from discrete state of transport to a continuum description of bed forms could be realized through a novel transport formula. With this aim, this study investigates the effect of surface moisture on the grain-scale transport mechanism by CFD-DEM coupling. The open-source package MercuryDPM is used for DEM simulation [3]. This includes a 1D RANS model for air flow field calculation and a liquid bridge model that simulates the liquid between the particles. From this study, it is found that particles behave differently in the lift-off process by wind and collision process because of the cohesion induced by liquid bridge. The moisture could change the critical wind condition for transport initiation, as well as the cessation threshold for saturated transport to be sustained. The dependencies of transport rate on the wind strength and moisture level are studied as well.
(1) Ellis, J. T.; Sherman, D. J.; Farrell, E. J.; Li, B. Aeolian Research 2012, 3, 379–387.(2) Swann, C.; Lee, D.; Trimble, S.; Key, C. Aeolian Research 2021, 51, 100712.(3) Weinhart, T.; Orefice, L.; Post, M.; van Schrojenstein Lantman, M. P.; Denissen, I. F.; Tunuguntla, D. R.; Tsang, J.; Cheng, H.; Shaheen, M. Y.; Shi, H., et al. Computer physics communications 2020, 249, 107129.
 

 

 
On the Projected Changes in the Seasonality and Magnitude of Precipitation Extremes
Authors: Treppiedi Dario , Villarini Gabriele , Bender Jens , Noto Leonardo
Published: February 2023

Heavy precipitation events are strongly affected by climate change and there is a high confidence that these extremes will become more frequent and more severe in the future. Moreover, potential changes in the seasonality of these events are important in terms of planning and preparation against these events. While efforts have been focused on changes in the magnitude and seasonality of extreme precipitation events, these studies have treated these two quantities separately.In order to overcome to this limit, a different perspective is here used by modeling the seasonality and magnitude of extreme precipitation events together through circular-linear copulae. We perform analyses at the global scale and develop bivariate models for an historical dataset. The outputs provided from several global climate models from the sixth phase of the Coupled Model Intercomparison Project (CMIP6) and Shared Socioeconomic Pathways (SSPs) from 1-2.6 to 5-8.5 are then used to examine the joint projected changes in the seasonality and magnitude of extreme precipitation at the global scale.
Microbial communities differ in warm and cold periods over >150,000 years
Authors: Zhong Zhi-Ping , Li Yueh-Fen , Davis Mary , Van Etten James , Mosley-Thompson Ellen , Sullivan Matthew , Rich Virginia , Thompson Lonnie
Published: February 2023

Glacier-archived records are powerful windows into past climates and ecosystems, but variation in co-preserved microbiota is rarely characterized over long time periods or connected to changing climates. In a 310-meter ice core from the Guliya ice cap, Tibetan Plateau, we linked microbial communities to concomitant climatic conditions across 33 depths, spanning at least the last 150,000 years. Communities differed significantly between cold and warm periods, and among the three major climate epochs Holocene, Last Glacial Stage (LGS), and Pre-LGS. Although source inputs varied during these periods, the microbial changes appeared independently impacted by climate as well. Co-occurrence network analyses suggested the importance of glacial surface-growing communities, and their phototrophs, to the preserved microbial record. The inferred microbial growth (by cell densities, diversity, and potential doubling times pre-compaction into solid ice) on Guliya’s surfaces was higher during cold periods than warm periods, likely associated with deeper snow and firn layers under colder conditions. Three Cyanobacteria “blooms” were captured in the record, and were significantly correlated to overall microbial concentration and diversity, as well as the abundance of two heterotrophic photosynthetic clades (the genus Geodermatophilus and the class Chloroflexia). Taxonomically, 6 genera were historically persistent and dominant throughout the record (Polaromonas, Flavobacterium, Massilia, Aquaspirillum, Pedobacter, and Cryobacterium), one of which (Cryobacterium) exhibited a shift in dominant strains from the Pre-LGS to the LGS, indicating a possible speciation event. Collectively, these findings advance our understanding of ancient glacier-archived microbial communities and the ecological forces they experienced, provide evidence for microbiological responses to the prevailing climate regime, and may shed new light on the microbial evolution across a long-term history over at least the last >150,000 years.
Comparison of the precursory effects in lithosphere, atmosphere and ionosphere of three large earthquakes with comparable magnitude: the cases of 2019 Kermadec Islands (NZ) and Ridgecrest (USA) earthquakes and 2021 Maduo (China) earthquake
Authors: De Santis Angelo , Campuzano Saioa A. , Calcara Massimo , Cianchini Gianfranco , D'Arcangelo Serena , De Caro Mariagrazia , Di Mauro Domenico , Fidani Cristiano , Nardi Adriano , Orlando Martina , Perrone Loredana , Piscini Alessandro , Sabbagh Dario , Soldani Maurizio
Published: February 2023

Three earthquakes of comparable magnitude and in different tectonic contexts occurred on 15 June 2019 (M7.2) in New Zealand (Kermadec Islands), on 6 July 2019 (M7.1) in California (Ridgecrest) and on 21 May 2021 (M7.3) in China (Maduo) (dates in UT). We applied a multiparameter - multilayer approach to lithospheric, atmospheric and ionospheric data, the latter taken from CSES  and Swarm satellites, before the mentioned large earthquakes to detect potential pre-earthquake anomalies. In all case studies, we note the following: a) similar precursor times of occurrences, confirming the Rikitake law for which the larger the earthquake magnitude the longer the anticipation time of the precursor and b) a clear acceleration of the possible precursory anomalies before each mainshock, as typical of critical systems approaching a critical state. We propose an interpretative model to take into account the chain of detected phenomena.
Crop residue biochar’s role in healthy soil and food production: the potential tool to assist organic farming
Authors: Pan Genxing , Liu Cheng , Li Lianqing , Liu Xiaoyu , Bian Rongjun , Yang Li
Published: February 2023

Biochar’s multifaceted benefits for soil quality have been well acknowledged whilst its particular effects on plant health have not yet been thoroughly understood. Plant health is conceived as the plant capacity of resource efficient production, of tolerance to abrupt stresses by extreme weather events, of bio-control or bio-defense of soil-borne pathogens and of safe synthesis of functional compounds for food quality and human nutrition. Biochar soil amendment provided quick restoration of soil organic matter, soil structure build-up and stabilization of toxic metals and organic pollutants in soil, benefiting safe growth of crops.  Utilization of biochar for blending mineral nutrients creates slow releasing fertilizers so as to increase nutrient use efficiency and reduce the fertilizer dosage while supplement OC and minor elements to soil. Moreover, use of biochar for co-composting animal wastes to produce novel biochar-based composts is shown an useful application of biochar in organic agriculture. In addition, biochar use in anerobic digestion and as sorbent in waste water and waste slurry is being explored in rural sector. As a particular case for rice crop production, biochar from rice residue to healthy paddy and rice can be managed into a closed loop: rice straw feeding cows and the manure into biochar-compost for soil amendment (reducing methane emission from residue incorporation), rice husk gasification for bioenergy for energy displacement and biochar for blending chemical fertilizers (reducing nutrient release to waters and nitrous oxide emission) for rice production, all these promoting healthy rice production.  improvement). It could be a biochar-centralized bioeconomy in agriculture could become a global solution for reverse soil degradation, environment pollution and soil C loss while significantly mitigating the climate change. The scope and standardization of biochar for crop production should be a research priority for biochar science and technology in agriculture.
Large-scale extraction of check dams and silted fields on the Chinese Loess Plateau using ensemble learning methods
Authors: Zhao Jianlin
Published: February 2023

Check dams are an effective soil and water conservation measure which is widely constructed in the world. A large number of check dams have been installed on the Chinese Loess Plateau during the last 70 years, which have played an important role in sediment control and soil conservation. However, high-resolution and large-scale mapping of the location of the check dam and silted field is absent, thus hampering the efficient management of the check dams and quantitative evaluation of their eco-environmental benefits. In this study, we present a methodological framework to extract silted fields and estimate the location of the check dam at a pixel level by using three ensemble learning methods combined with a novel resampling procedure to lessen the influence of class imbalance. Our results indicate that the distribution of check dams and silted fields is a typical imbalanced binary classification problem that the amount of silted field samples only accounted for 4% of the total randomly collected samples, which has a significant impact on the accuracy of both model training and validation. By using the random under-sampling method, the optimal imbalance ratio was determined for each model, combined with the optimal modeling parameters and 23 features, to train and validate the model. The validation results on the testing set show that the F1-score of Random Forest, Extreme Gradient Boosting, and EasyEnsemble model for the silted field is 0.7501, 0.7664, and 0.7754, respectively. The feature importance analysis shows that three macro-terrain features and multi-temporal spectral indices contributed mostly to the accurate extraction of silted fields, among which the multi-temporal vegetation cover change index has the highest feature importance for all models. Applying the tuned model to the whole Wuding River catchment, we produced a 10m-resolution silted fields and check dams map showing that there are ca. 10,500 check dams correspondingly forming ca.283.3 km² area of silted fields. This study provides an important and efficient methodological framework for quick mapping of check dams and silted fields at a high-resolution and a large scale with addressing the imbalanced classification problems.