bluuebunny/crossref_metadata_2025 huggingface dataset:
Vulnerabilities of Global Supply Chains to Agricultural Production Disruptions Caused by Individual and Compound Climate Shocks
Authors: Zhang Shuo , He Xiaogang
Published: March 2024

Climate change induced extreme precipitation poses a significant threat to agricultural production. Such impacts extend beyond local agricultural production regions, generating remote and cross-sector impacts that disrupt global supply chains (GSCs). While the direct impacts of extreme precipitation on agricultural production have been widely studied, how such local impacts cascade through supply chain networks to remote places remains elusive, partly because of the complex interdependencies within the global trade systems. To address this, we propose a Resilience Enhancement in Supply Chains Under Environmental Shocks (RESCUES) framework. RESCUES couples an agricultural production loss model with a dynamic recursive economic network model. It allows us to identify channels through which the impacts of climate change on agricultural production propagate along GSCs to interconnected sectors and regions. We design nine climate shock scenarios (i.e., dry, wet, and compound precipitation anomalies with extreme, severe, and moderate levels of severity) using the latest Coupled Model Intercomparison Project Phase 6 (CMIP6) under two Shared Socioeconomic Pathways (SSPs) scenarios (SSP126 and SSP585). We then use RESCUES to simulate the GSCs dynamics over 2016-2050 under these nine scenarios. We find that direct agricultural losses driven by local precipitation anomalies can spread through GSCs to a wider range of countries and regions across the globe, creating large spatial spillover effects with direct and indirect economic losses. We estimate that the averaged per event total value-added (VA) losses caused by compound extremes is around $20.4/22.6 billion under SSP126/585, followed by dry extremes ($16.4/15.0 billion) and wet extremes ($8.7/11.6 billion). Moreover, the global distribution of direct and indirect losses exhibits high spatial heterogeneity. Countries with large agricultural outputs tend to have both high direct and indirect VA losses, especially in China, India, the United States, Russia, and Brazil. In contrast, poorer countries, such as Tanzania, Sudan, Myanmar, Yemen, Afghanistan, and Nepal, experience relatively larger direct losses, while rich regions heavily dependent on agricultural imports, including Hong Kong, Qatar, and Singapore, suffer relatively larger indirect losses. Considering that nations frequently implement export restrictions to ensure food self-sufficiency, we further design a hypothetical scenario to assess the global trade and economic impacts of near-term (2025-2030) agricultural export restrictions in four key food production regions (China, India, the United States, and Indonesia) under extreme precipitation anomalies. Our study highlights the importance of an integrated and comprehensive assessment of the risk footprint of climate change-related shocks, encompassing both direct and indirect impacts on GSCs. 
Ocean heat uptake and interbasin redistribution driven by anthropogenic aerosols and greenhouse gases
Authors: Li Shouwei , Liu Wei , Allen Robert  J. , Shi Jia-Rui , Li Laifang
Published: March 2024

Anthropogenic aerosols and greenhouse gases have played important roles in modulating the storage and distribution of heat in oceans since the industrial age. Here we isolate and quantify the effects of both using coupled climate model simulations. We show that, relative to the pre-industrial ocean, the Southern Ocean imports heat from the Indo-Pacific Ocean but exports heat into the Atlantic Ocean in response to anthropogenic aerosols. Ocean heat uptake diminishes in the subpolar Atlantic. Alterations in ocean circulation and temperature have a weak compensation in contributing to interbasin heat exchange. Consequently, interbasin heat exchange contributes comparably to ocean heat uptake changes to modifying the stored heat in the Atlantic and Indo-Pacific. The greenhouse-gas-associated changes are the opposite of the aerosol-associated changes. Anthropogenic greenhouse gases promote the ocean heat uptake in the subpolar Atlantic and allow the Southern Ocean to import heat from the Atlantic but export heat to the Indo-Pacific. The cause of this ocean heat redistribution is distinct from the aerosol-forcing scenario, seeing that ocean circulation effects are strongly offset by temperature shifts. Accordingly, interbasin heat exchange is much less important than ocean heat uptake changes for greenhouse-gas-associated ocean heat storage. Our results suggest that the aerosol-driven changes in ocean circulations and associated interbasin heat transports are more effective in altering oceanic heat distribution than those driven by globally increasing greenhouse gases.
Ambient noise tomography of Mount Isa, Northern Queensland in Australia
Authors: Chang Ao , O'Neill Craig
Published: March 2024

The Mount Isa region in Northern Australia is a world-class mining complex, yielding significant combined outputs of lead, silver, copper and zinc. This zone consists of sedimentary layers from lower to middle Proterozoic era with a mix of bimodal volcanic rocks and plutonic formations. A significant crustal structure, known as the Gidyea Suture zone, exists within the Mt Isa succession, and its geological history and association with the mineralisation at Mt Isa are unclear.  Previous surveys highlighted the distinct geophysical characteristics of region, in terms of magnetic and gravity anomalies, magnetotellurics conductivity anomalies, and structural features from deep seismic refraction. The characteristics of the mid-crustal zone has been implicated in mineralisation models, and imaging mid to deep crustal structures is important for mineral exploration. In this depth zone, passive seismic surveys show apparent advantages due to their low cost and continuous recording, when contrasted with active seismic surveys, or indeed earthquake tomography in this typically low-activity seismic zone.  In this study, we use the legacy noise data collected from 53 3-component temporary seismic sensors with 50km spacing covering the Mount Isa area deployed from June 2009 to March 2011, and perform ambient noise tomography (ANT) to model the shear wave velocity (Vs) crustal structure. 681 cross-correlations (CCs) of recordings over two weeks between each pairwise stations are used to calculate the empirical Green’s function (EGF) to construct the impulse wavefield. The dispersion curves of the fundamental mode of Rayleigh surface waves are extracted from vertical components of the CCs. Separating the fundamental mode from the other higher modes in the group-velocity map is usually hard to identify. A modified frequency-time analysis (FTAN) based on the global seismology code CPS is used for digitising dispersion curves here. Then the dispersion curve is inverted using a bespoke Markov-Chain Monte Carlo approach to build 1D Vs profiles, which are finally used to construct a 3D shear wave velocity model across the area of interest. We discuss the comparison of the legacy passive seismic data to the results of other geophysical measurements, to provide a new understanding of terrane evolution and crustal structure of Northern Queensland.
UrbanTALES: A comprehensive dataset of Urban Turbulent Airflow using systematic Large Eddy Simulations
Authors: Nazarian Negin , Lu Jiachen , Hart Melissa , Krayenhoff E. Scott
Published: March 2024

The urban canopy layer (UCL) is characterized by a heterogeneous flow pattern that responds to heterogeneous urban geometries. The varying heights and layouts of buildings play a pivotal role in shaping this spatial variability, as they block, divert, and slow wind and determine the exchange of momentum and energy above the urban canopy. When representing these complex dynamics, however, research has conventionally relied on microscale simulations conducted over limited (often idealized) building arrays. Extending the findings to realistic urban neighborhoods and urban parameterizations presents a clear limitation, as evidenced by discrepancies in multi-model comparisons with observational data in cities.More extensive datasets of urban airflow are needed to cover a range of realistic urban neighborhoods and provide a more holistic analysis of turbulent flow in different urban characteristics. Responding to this gap in the field, we developed a historically extensive and comprehensive dataset of Urban Turbulent Airflow based on state-of-the-art  Large Eddy Simulations (UrbanTALES). The dataset includes 400 urban layouts with both idealized and realistic configurations. Realistic urban neighborhoods were obtained from major cities worldwide, incorporating variations in plan area densities [0.0625-0.64] and height distributions [4-70m]. Idealized urban arrays, on the other hand, include two commonly studied configurations (aligned and staggered arrays), featuring both uniform and variable height scenarios along with oblique wind directions. UrbanTALES offers canopy-averaged data as well as 2D and 3D flow fields tailored for different applications in urban climate research. The dataset provides time-averaged wind flow properties, as well as second- and third-order flow moments that are critical for understanding turbulent processes in the UCL. Here, we describe the UrbanTALES dataset and its application, noting the unique opportunity to deploy a comprehensive representation of realistic urban neighborhoods for a) revisiting neighborhood-scale urban canopy parameterizations in various models and b) informing in-canopy flow and turbulent analyses. Furthermore, we discuss the application of this dataset for training Machine Learning algorithms for pedestrian wind speed. 
Blue Carbon Management for Climate Resilience
Authors: Liu Dahai , Dong Tong
Published: March 2024

Global warming, accelerating at an alarming rate, has thrust climate change into the forefront of global concerns. The recent warning from the World Meteorological Organization (WMO) about the record-low Antarctic sea ice coverage serves as a stark reminder of the urgency surrounding environmental issues in the twenty-first century. Climate change is undeniably one of the most pressing challenges facing humanity today, with far-reaching implications for our survival and socio-economic development.In response to the escalating crisis, there has been a global call to action, urging nations to limit the rise in global temperatures to 1.5 to 2 degrees Celsius. Oceans, as the primary regulators of climate change, emerge as pivotal players, holding approximately 93 percent of the Earth's CO2. In exploring solutions, the concept of "blue carbon" has emerged, drawing attention to coastal ecosystems' carbon sequestration potential. However, the effective management of blue carbon presents a myriad of challenges, necessitating a holistic approach. There is a growing consensus that international standards for assessing marine carbon sinks are lacking. Experimental methods, including those proposed by the Intergovernmental Panel on Climate Change (IPCC) and the United Nations Environment Programme (UNEP), have been explored. However, the absence of a universally accepted framework impedes progress. It is within this context that the First Institute of Oceanography (FIO), Ministry of Natural Resources (MNR), China, has embarked on a pioneering initiative, developing China's first comprehensive marine carbon sink accounting standard. The standard, structured into five parts—Scope, Documents, Definitions, Accounting, and Appendix—provides a vital foundation for research, development, and management of blue carbon projects. Key terms and definitions, including ocean carbon sinks, mangroves, salt marshes, seagrass beds, phytoplankton, macroalgae, and shellfish, contribute to a robust scientific framework for the comprehensive understanding of marine ecosystems.Despite these advancements, challenges persist in blue carbon management, requiring focused attention. From a scientific perspective, understanding carbon sink mechanisms, potential, and capacity is essential. At the technical level, the development of observation systems, monitoring data, and international standards is crucial. On a practical level, conducting high-level dialogues, implementing international blue carbon plans, and establishing global blue carbon governance structures are imperative for improving the quality and functioning of marine ecosystems. In conclusion, the journey towards effective blue carbon management is a complex but imperative one. Standardizing practices, promoting international cooperation, and encouraging transactions related to carbon sink accounting are pivotal steps in our collective efforts to mitigate the impacts of climate change and safeguard the health of marine ecosystems worldwide.
Significant Enhancement of Turbulence Cascade Rates Downstream of Quasi–perpendicular Bow Shock at Mars
Authors: Jiang Wence , Li Hui , Hadid Lina , Andrés Nahuel , Daniel Verscharen , Wang Chi
Published: March 2024

Compressible plasma turbulence is prevalent in planetary plasma environments. However, our current understanding of turbulence injection and dissipation in the highly-compressible magnetosheath is still quite limited. Previous studies have suggested that pickup ion instabilities originating from the far-extended neutral exospheres of Mars may contribute to energy injection, leading to the frequent observation of plateau-like spectral characteristics in the Martian magnetosheath. Nonetheless, it remains unclear how the turbulence cascade rates vary with local parameters related to the bow shock geometry and pickup ions. In this investigation, we conduct a joint analysis of Tianwen-1 and MAVEN data to unveil spectral characteristics and the varying turbulence cascade rates under different bow shock geometries. By employing the exact laws of compressible magnetohydrodynamics turbulence, we observe a systematic increase in cascade rates with the shock normal angle. As the geometry transitions from quasi-parallel to quasi-perpendicular, the ratio between the turbulence cascade rates of the upstream solar wind and the downstream magnetosheath increases by 20-30 times. Furthermore, we find that the turbulence cascade rate of cases exhibiting plateau-like spectral shapes increases more significantly with the shock normal angle compared to those without plateau-like features. Our findings offer new insights into understanding turbulence injection and dissipation downstream of collisionless super-critical bow shocks in space and astrophysical plasmas.
The role of midlatitude dry air during the withdrawal of the Indian monsoon
Authors: Deoras Akshay , Turner Andrew , Volonté Ambrogio , Menon Arathy
Published: March 2024

The Indian summer monsoon (ISM) supplies over 75% of the country’s annual precipitation, profoundly impacting lives of over a billion people. Significant variability in the timing of its onset and withdrawal has a direct impact on the agricultural sector and other users of water resources. Previous studies have shown that a wedge of mid-tropospheric dry air emanating from the midlatitudes is present over India during early summer, which is much shallower in the vertical toward the southeast of India. Following the strengthening of low-level monsoon winds during the onset, the dry air retreats from the southeast due to increased moistening by shallow cumulus congestus clouds, driving the north-westward progression of the ISM. The withdrawal of the ISM is observed to progress in a southeast direction during September–October, but there is a lack of a conceptual model. In this study, we use observations and the ERA5 reanalysis to understand the dynamics and thermodynamics of the withdrawal. We find that a mid-level dry intrusion re-appears over the northwest of India around mid-September. Vertical profiles associated with this dry air show how the most unfavourable environment for deep convection occurs in the northwest, where the withdrawal occurs first. As the withdrawal progresses, the wedge of dry air deepens throughout its horizontal extent and descends. This stabilises the troposphere, suppressing deep convection and ultimately driving the withdrawal toward the southeast. By mid-October, the dry air engulfs most of India, causing the ISM to withdraw from the entire country. Thus, the strengthening of the mid-level dry advection from the midlatitudes can explain the withdrawal of the ISM, and the mechanism driving the local withdrawal can be considered as the reverse of that at play during the progression of the onset. This work establishes a new paradigm for the withdrawal of the Indian monsoon in terms of midlatitude interactions, which could be tested for other monsoon regions.
Pleistocene drainage reorganization of the upper reaches of the Han River and its tectonic significance
Authors: Ju Dali , Yang Zhao
Published: March 2024

Drainage systems are highly sensitive to landform changes, and their formation and evolution history are of great significance for understanding regional tectonic-climatic processes and ecological environmental changes. Since the Cenozoic, the uplift and expansion of the Tibetan Plateau have profoundly influenced the landforms and drainage patterns in its surrounding area. The Qinling-Daba Mountains are located on the northeastern margin of the Tibetan Plateau, and the Han River, as the largest tributary of the Yangtze River, originates from the southern flank of the Qinling Mountains and flows from west to east between the Qinling and Daba Mountains, whose evolution history may document abundant clues of the expansion of the Tibetan Plateau and regional tectonic-climatic responses. Previous studies suggested that a significant river reorganization event may have occurred in the upper reaches of the Han River. However, the timing and mechanism are still vague. In this study, the evolution history of the upper reaches of the Han River is reconstructed through terrace mapping, paleocurrent measurements, K-feldspar Pb isotope provenance analysis, and quartz electron spin resonance (ESR) dating. Combined with the fault kinematic analyses, it is believed that before 0.4 Ma, the Paleo-Han River flowed directly eastward along the Ankang Basin. Between 0.4-0.15 Ma, the continuous left-lateral strike-slip movement along the Ankang Fault resulted in vertical uplift at its compressional bend and caused the Han River to flow southward and bypass into the Daba Mountains. This river evolution event within the Qinling region reflects the adjustment process of the peripheral water systems and landforms under the influence of the expansion of the Tibetan Plateau.
Terrain effects on microwave emission transmission of snowpack and snow depth retrieval
Authors: Che Tao , Dai Liyun
Published: March 2024

The existing snow depth products have mainly focused on influence of varying snow characteristics and forests, while neglecting the complicated mountainous terrain. Therefore, examining the influence of mountainous terrain on microwave radiation transmission of snowpack is beneficial for improvement of snow depth retrieval algorithms in mountainous areas. In this study, we established microwave emission transfer model of snowpack in Mountainous areas within the framework of MEMLS, thereafter, called MEMLS-T. MEMLS-T considers the influence of complicated terrain on the microwave radiation transmission of snowpack from three perspectives: 1) the varied hill slopes alter the local incidence angle; 2) the diverse hill slopes and aspects induce the polarization rotation; 3) The reduced sky visibility in mountainous regions results in an escalation of downward background radiation reaching the snow surface, as a consequence of the illumination from neighboring slopes. We simulate brightness temperatures at varying sky visibilities, slopes and aspects using MEMLS-T, and find that, in compared with flat terrain, brightness temperature gradient decreases in mountainous area, and the extent of reduction depends on complexity (Figure 1). The brightness temperatures are simulated based on various spatial resolutions of DEM and integrated into a grid of 6.25km×6.25km. The results reveal that coarser DEM results in greater sky visibility (Figure 2) and higher brightness temperature (Figure 3). Therefore, a fine DEM is necessary to simulate the brightness temperatures in mountainous areas. Additionally, the observation footprints vary with satellites and frequencies, resulting in discrepancies in snow depth retrieval and temporal consistency.figure 1Brightness temperature difference between K and Ka bands varies with aspect, slope and sky radiationfigure 2 Comparison of sky visibility obtained from DEMs with different resolutions.Figure 3 Comparison of brightness temperature simulated from DEMs with different resolutions
Observational and Theoretical Study of Lower Hybrid Drift Waves
Authors: Arya Neetasha , Kakad Amar
Published: March 2024

One of the most important diamagnetic current driven instability transverse to the magnetic field is lower hybrid drift instability (LHDI) which excites lower hybrid drift waves (LHDW). LHDI gives rise to anomalous resistivity which further leads to onset of magnetic reconnection. Because of its high anomalous collision frequency, LHDI enhances the rate of transverse diffusion. The lower hybrid frequency (LHF) ranges between electron and ion cyclotron frequency which is a natural resonance. LHDW is generally observed in transition layer regions and magnetic reconnection sites, where the gradient in density occurs. We are presenting electromagnetic kinetic model including gradients in density and magnetic field, finite parallel wavenumber and non-thermal particle distribution function or kappa velocity distribution function.  The effect of the aforementioned factors on the growth rate of LHDI in different plasma beta circumstances has been thoroughly investigated and will be discussed. Space observation of drift driven wave using MMS spacecraft will also be discussed.
Multi-model simulation of solar geoengineering indicates avoidable destabilization of the West Antarctic ice sheet
Authors: Moore John , Chen Yangxin , Yue Chao , Jevrejeva Svetlana , Visioni Dan , Uotilla Petteri , Zhao Liyun
Published: March 2024

Heat transported in Circumpolar Deep Water is driving the break-up of ice shelves in the Amundsen Sea sector of Antarctica, that has been simulated to be unavoidable under all plausible greenhouse gas scenarios. However, climate intervention scenarios have not been considered. Solar geoengineering changes global thermal radiative balance, and atmospheric and oceanic transportation pathways. We simulate stratospheric aerosol injection (SAI) designed to reduce global mean temperatures from those under the unmitigated SSP5-8.5 scenario to those under the SSP2-4.5 scenario with six CMIP6-class Earth System Models. These consistently show intensified Antarctic polar vortex and sub-polar westerlies, which mitigates changes to easterly winds along the Amundsen Sea continental shelf compared with greenhouse gas scenarios. The models show significantly cooler Amundsen Sea waters and lower heat content at 300-600 m under SAI than with either solar dimming or the SSP5-8.5 unmitigated greenhouse gas scenarios. However, the heat content increases under all scenarios compared with present day suggesting that although vulnerable ice shelves would continue to thin, the rate would be lower for SAI even with SSP5-8.5 specified greenhouse gases, than for the moderate (SSP2-4.5) scenario. The simulations here use climate interventions designed for global temperature targets; interventions targeted at preserving the frozen high latitudes have also been proposed that might be expected to produce bigger local effects, but potentially deleterious impacts elsewhere. Considering the huge disruptions to society of ice sheet collapse, more research on avoiding them by intervention technology is a moral imperative. 
A Summary and Comparison of the latest GPCP Daily and Monthly Products (Version 3.2) and the Plan Forward
Authors: Behrangi Ali , Huffman George J. , Adler Robert F.
Published: March 2024

This presentation is composed of four major parts: (1) a brief overview of the latest Global Precipitation Climatology Project (GPCP) Daily and Monthly products (V3.2) and satellite-gauge input data sets used in them, (2) comparison of the GPCP V3.2 products with the previous version of GPCP Daily (V1.3) and Monthly (V2.3) products and highlighting major changes, (3) assessment of the GPCP V3.2 products over the Oceans using Passive Aquatic Listeners (PALs) and over sea ice using snow depth data from combination of ICESat-2 and Cryosat-2 observations, and (4) a brief description of the plans towards the next generation of the GPCP products. GPCP is a popular combined satellite-gauge precipitation dataset in which the long-term CDR standards of consistency and homogeneity are emphasized, going back to 1983 for GPCP Monthly V3.2. Several major changes occurred in V3.2 including: (1) moving from Monthly 2.5°x2.5° and Daily 1.0°x 1.0° spatial resolution in V2.3 to 0.5°x0.5° for both Daily and Monthly products, (2) addition of more recent satellite data such as the Tropical Rainfall Measuring Mission (TRMM), CloudSat, Global Precipitation Measurement (GPM) mission, and the Gravity Recovery and Climate Experiment (GRACE) mass change observations, and (3) use of new precipitation retrieval and calibration methods. Compared to V2.3, GPCP V3.2 shows about  6.5% increase in global oceanic and about a 4.5% increase in global (land and ocean) precipitation rates with some major changes over the ocean between 40 oS and 60 oS. Similar to V2.3, a near-zero global precipitation trend was observed in V3.2.  However, regional trends, which are substantial, remain generally similar between V2.3 and V3.2. Evaluations over the oceans using PALs showed that GPCP v3.2 substantially outperforms GPCP V2.3 in representing rain occurrence and rain intensity at a daily scale, likely due to the use of IMERG in the daily product of GPCP V3.2. Comparison of the GPCP V3.2 product over sea ice, suggests that GPCP V3.2 generally captures the snowfall accumulation pattern over sea ice, compared to that obtained from the combination of ICESat-2 and Cryosat-2 observations, as well as that from ERA5. However, the products show considerable differences in the amount of snowfall accumulation, with ERA5 often showing the highest values. We will end the presentation by briefly discussing our plans for further improvement of GPCP including higher spatial and temporal resolution, lower latency, and the use of more advanced gauge analysis and precipitation retrieval methods.
Monsoonal Transboundary Impact on Air Quality over Dhaka and Kolkata Region 
Authors: Faruk Tashnia , Khan Firoz
Published: March 2024

Air pollution has become a prime concern globally due to the escalation of anthropogenic activities and adverse meteorological conditions in recent years. The significant consequences of air pollution, manifesting in adverse ecosystem health effects and economic losses, highlight the urgency of assessing its impact on a regional to global scale. However, there is a lack of systematic investigations, particularly in the context of information deficiency on air pollution in Bangladesh. Therefore, this study aims to investigate the seasonal variations in air quality over Dhaka and Kolkata, with a specific focus on the summer monsoon (May-July). While winter pollution in these cities has been extensively explored in several studies, less attention has been given to understanding the dynamics of monsoon season. This study incorporates Copernicus Atmosphere Monitoring Service (CAMS) reanalysis data to evaluate the influences of both regional and global factors on air quality. Specific emphasis has given on determining the correlation between air pollutants (PM2.5, carbon monoxide, black carbon, sulfur dioxide, ozone, nitrogen dioxide) and meteorological parameters (temperature, humidity, wind components, atmospheric pressure, boundary layer height and precipitation). This understanding is crucial as it forms a strong foundation for developing effective control and prevention strategies of air pollution for this region. In addition, by correlating metrological conditions between Dhaka and Kolkata, the study aims to evaluate the transboundary effects on pollutant dispersion. The potential impact of Sahara fires on air quality of these two cities is investigated using concentration-weighted trajectory analysis (CWT), extending the geographical domain to include the entire South Asian region. The findings not only contribute to the scientific understanding of local air quality but also have broader implications for regional and global atmospheric interactions. The study's insights provide a basis for informed policymaking and facilitate more effective nature based mitigation and control management strategies during the summer monsoon season in these densely populated urban areas.
Precise monitoring of subduction plate coupling status on the basis of DONET and borehole data analyses
Authors: Ariyoshi Keisuke , Matsumoto Hiroyuki
Published: March 2024

We have detected an event of pore pressure changes (hereafter, we refer it to “pore pressure event”) from borehole stations in real time in March 2020 and March 2023, owing to the network developed by connecting three borehole stations to the Dense Oceanfloor Network System for Earthquakes and Tsunamis (DONET) observatories near the Nankai Trough. Slow earthquake is thought to have longer duration time with smaller stress drop than regular earthquake under the same magnitude. This means that the slow earthquake is more sensitive to external stress perturbation and useful to monitor the processes of stress accumulation and release. However, the pore pressure is also affected by tidal and oceanic fluctuations. To overcome this problem, we use the seafloor pressure gauges of DONET stations nearby boreholes instead of the reference by introducing time lag between them. The obtained results demonstrate the detectability of volumetric strain change for nano-scale. We also investigate the impact of seafloor pressure due to ocean fluctuation on the basis of ocean modelling, which suggests that the decrease of effective normal stress from the onset to the termination of the SSE is explained by Kuroshio meander and may promote updip slip migration, and that the increase of effective normal stress for the short-term ocean fluctuation may terminate the SSE as observed in the Hikurangi subduction zone. The evaluation of the ocean impact is to be applied to a fiber-optic submarine cable, and 50 km-long distributed acoustic sensing (DAS) recordings, where the DAS measurement can be sensitive for hydroacoustic signals in a frequency range from 0.1 to a few tens of Hz.
Quantifying runoff variability and Glacier thickness variations from 2011 to 2020 in Gangotri glaciated region, India
Authors: Singh Japjeet , Singh Vishal , Ojha Chandra Shekhar Prasad
Published: March 2024

Recent research indicates a substantial reduction in glacier mass within the Himalayas, primarily attributed to rising temperatures, leading to heightened uncertainties regarding downstream water availability. This study specifically investigates the impact of variations in thickness within the Gangotri glaciers, focusing on the Raktavaran and Chaturangi regions, during the period from 2011 to 2020. Employing a two-model coupling approach, the study integrates Glacier Bed Topology (GlabTop2) and Spatial Process in Hydrology (SPHY). Calibration is meticulously carried out through a two-step process, incorporating observed discharge data and Moderate Resolution Imaging Spectroradiometer (MODIS) snow cover information. The achieved R2 values for SPHY-modeled runoff (Q) and observed Q at Bhojwasa exhibit a commendable level of comparability, standing at approximately 0.73 on a daily scale. The analysis highlights that glacier-derived Q contributes to 22.11% of the total Q, with snow-derived Q accounting for 66.91%, underscoring their distinct roles in the hydrological system. A comparative assessment between Chaturangi and Raktavaran with the Gangotri glaciers reveals that the latter experienced a more substantial rate of thickness change, resulting in an estimated reduction of about 9.40% in mean glacier thickness over the period from 2011 to 2020. In consideration of these findings, the study emphasizes the urgent necessity for a comprehensive understanding of the intricate interplay between glacier dynamics and hydrological processes within the context of changing climatic conditions. This research contributes valuable insights that can serve to inform adaptive strategies and resource management practices aimed at addressing the evolving challenges posed by glacier melt and its downstream implications.
Metals in Earth’s Magnetosphere: From Ionosphere or Moon? 
Authors: Lin Mei-Yun , Poppe Andrew
Published: March 2024

Recent observations by the Geotail and Cluster missions in the magnetosphere have revealed the presence of singly charged metallic ions, such as Mg+ and Fe+. However, the origins and transport mechanisms of these metallic ions are unknown. Metallic ions are prevalent in the Earth's lower atmosphere, primarily produced from the ablation of meteoroids and the formation of metal layers. Similarly, metallic ions are also common in the vicinity of the Moon's surface, where they are created from the ionization of the lunar exosphere, a thin neutral atmosphere that surrounds the Moon. To deepen our understanding of the sources of the metallic ions in the magnetosphere, this study develops different strategies to evaluate the contributions of metallic ion outflow from the ionosphere and the Moon across different solar and geomagnetic conditions.  To estimate the metallic ion outflow from the ionosphere, we utilize a physics-based model, PWOM, which solves the transport of ionospheric outflow for all the relevant ion species, such as H+, He+, N+, O+, and molecular ions. As metallic ions are mainly produced via charge exchange between molecular ions and metal atoms in the ionosphere, the abundance of metallic ion outflow is represented by the densities of molecular ions with adjusted ratios. In addition, the metallic ion upflow will be further accelerated to outflow in the high-altitude ionosphere via the energization of wave-particle interaction. This vertical transport of metallic ions is further tracked by PWOM and shows a strong connection with the wave energy input. On the other hand, metallic ion outflow from the Moon is inferred from LADEE and ARTEMIS observational data. These pickup ions are generated through charge exchange or electron impact from the metallic neutrals, which are primarily produced through either charged particle sputtering or micrometeoroid impact vaporization of the lunar surface. The abundances of metallic neutrals are derived from information on sputter yields and observed ion fluxes. Once the densities of neutral metal species are obtained, the metallic pickup ion fluxes are further calculated based on the relevant ionization cross sections with incoming electron and ion fluxes to the lunar exosphere. We use in-situ ARTEMIS observations of ion and electron fluxes to properly calculate these ionization rates.  This study will be the first to compare the contributions of ionospheric outflow and lunar pickup ions to the magnetosphere. Moreover, by utilizing observational data from ARTEMIS, the variations of sources of metallic ions will be analyzed as the Moon passes through the upstream solar wind, magnetosheath, and magnetotail. The differences between the outflow of metallic ions from the ionosphere and the Moon can be used as a tracer to better understand the transport and energization processes of heavy ion plasma in the magnetosphere. 
Modification of exploration of long‐term nutrient trajectories for phosphorus (ELEMeNT-P) model to quantify legacy phosphorus dynamics in a typical watershed of eastern China
Authors: Hao Wu , Dingjiang Chen
Published: March 2024

In response to gradually expanding populations and the demand for food, excess anthropogenic phosphorus (P) input to watersheds leads to accumulating large P reservoirs in land systems, which becomes a persistent source of P pollution to aquatic systems, hindering the effectiveness of implementing water quality management. Therefore, clarifying the cycling process of P in watersheds, quantifying the legacy effects of P and identifying the spatial distribution of legacy P are key scientific issues for effectively developing watershed P management. We applied a modification Exploration of Long-tErM Nutrient Trajectories-Phosphorus model in a typical agricultural watershed in eastern China, which can well quantify the dynamics of legacy P over 40 years along the land-aquatic continuum. Modification of P erosion loss module improved the efficiency metrics of the model. The model indicated that the lag time for legacy P effects in the watershed was up to 10 years. P inputs increased by 40% (5.1 kg P ha-1 yr-1-9.8 kg P ha-1 yr-1) between 1980 and 2000 and decreased by 55% (9.8 kg P ha-1 yr-1-3.4 kg P ha-1 yr-1) between 2000 and 2020. Riverine P export fluxes increased from 0.11 kg P ha-1 yr-1to 1.49 kg P ha-1 yr-1 (13-fold increase) from 1980 to 2012, and then decreased to 0.96 kg P ha-1yr-1from 2012-2020 years to 0.96 kg P ha-1 yr-1 (35% decrease). The modification model was effective in clarifying the spatial and temporal distribution of legacy P and proposed an effective method to guide watershed P management.
Introduction to an open-source tool for collective Earth System Model evaluation and benchmarking: PCMDI Metrics Package (PMP)
Authors: Lee Jiwoo , Ordonez Ana , Gleckler Peter , Ullrich Paul , Planton Yann , Dong Bo , Chang Kristin , Durack Paul , Valkonen Elina , Caron Julie
Published: March 2024

The PCMDI Metrics Package (PMP) is an open-source Python-based framework that enables objective "quick-look" comparisons and benchmarking of Earth System Models (ESMs) against observation-based reference datasets. The PMP, which is focused primarily on atmospheric quantities, has been used for routine and systematic evaluation of thousands of simulations from the Coupled Model Intercomparison Project (CMIP). Ongoing work aims for seamless application of the tool to the next generation of CMIP (CMIP7), with an aspiration to aid modeling groups during their development cycle. The latest version of PMP offers a diverse suite of evaluation capabilities covering large- to global-scale climatology and annual cycle, variability modes such as tropical and extratropical variability modes e.g., ENSO and MJO, regional monsoons, cloud feedback, and high frequency characteristics e.g., extremes. Current work is expanding the scope of PMP to include the evaluation of the following: (1) Quasi-Biennial Oscillation (QBO) and its teleconnection to MJO, (2) atmospheric blocking and rivers leveraging Machine Learning based pattern detection algorithms, and (3) polar and high-latitude regions by implementing sectional sea-ice area metrics. The PMP is also advancing its evaluation capabilities to help evaluate higher resolution simulations such as those from the HighResMIP, cloud-resolving E3SM experiments, and regionally downscaled products. This presentation will highlight the motivation for routine model evaluation, introduce the PMP, share progress on current polar metrics, and discuss future plans and opportunities to connect with ongoing efforts.
Effect of 137Cs desorption from sediment on the formation of dissolved 137Cs concentrations in dam discharge water
Authors: Tsuji Hideki , Funaki Hironori , Hayashi Seiji
Published: March 2024

In the region affected by the Fukushima nuclear accident in 2011, some freshwater fish shipments continue to be suspended owing to radioactive contamination (mainly 137Cs) of the aquatic environment. In predicting the future 137Cs contamination of aquatic organisms, investigations must focus on the dynamics of 137Cs in dissolved form, which is highly bioavailable and abundant in the environment. In particular, dam lakes that deposit large amounts of sediment contaminated with 137Cs and have a long residence time of water can substantially influence the dynamics of 137Cs in rivers, as suggested by prior research. This study focuses on the effect of desorption of 137Cs from lake sediment on the formation of dissolved 137Cs concentrations in dam discharge water, using the results from monitoring surveys at two dam lakes located near the Fukushima Daiichi Nuclear Power Plant.We collected inflow and discharge water from the Matsugabo and Yokokawa dams in Fukushima Prefecture every month from 2014 and measured the concentration of dissolved and particulate 137Cs in the water using the cartridge filter method. On the basis of these results, combined with flow data from the dam lakes, we estimated the annual budgets of 137Cs (inflow/outflow) in the dam lakes. For the particulate form, annual 137Cs inflow into the lakes decreased by more than 80% in most years, indicating that most of the inflow particles sedimented. For the dissolved form, the annual discharge of 137Cs was higher than the annual inflow of 137Cs, concurring with results from a neighboring dam lake. This increment suggests 137Cs desorption from the sediment.According to the monthly monitoring data, the dissolved 137Cs concentration in the dam discharge water at some periods showed a higher value than the peak value from the previous year. This phenomenon was observed when the reservoir storage rate of the dam lake fell below approximately 30%. To determine the main source of dissolved 137Cs in the dam lake, we investigated the horizontal distribution of the dissolved 137Cs concentrations at several points in Yokokawa dam lake and the vertical distribution of the dissolved 137Cs concentration at the center of the lake in August 2023, when the water level was very low. The concentration of dissolved 137Cs in the lake water was found to increase in the inlet part of the lake, while the concentration remained almost the same in the downstream direction from the site. The concentration of dissolved 137Cs at the center of the lake was almost unchanged vertically. This trend was different from the increase in the concentration of dissolved 137Cs in bottom water, previously observed at the same location (Tsuji et al., 2022). These results indicate that 137Cs desorption from sediment in the inlet area mainly led to the increase in the dissolved 137Cs concentrations in the lake water, in part owing to the low volume of flowing water.
Well-Posedness of the Dynamic Framework in Earth-System Model 
Authors: Lian Ruxu , Ma Jieqiong , Zeng Qingcun
Published: March 2024

The well-posedness of the dynamic framework in earth-system model (ESM for short) is a common issue in earth sciences and mathematics. In this presentation, the authors will introduce the research history and fundamental roles of the well-posedness of the dynamic framework in the ESM,  emphasizing the three core components of ESM, i.e., the atmospheric general circulation model (AGCM for short), land-surface model (LSM for short) and oceanic general circulation model (OGCM for short) and their couplings. In fact, this system strictly obeys the conservation of energy and is used to make better climate predictions. Then, some research advances made by their own research group are outlined. Finally, future research prospects are discussed.
Probing pH of Particle in HCO3-/CO32- System through Optical Tweezers Coupled with Raman Spectroscopy
Authors: Fan Chengyi , Zhao Chunsheng
Published: March 2024

Acidity stands as a pivotal physicochemical parameter influencing aerosol particles, impacting their morphology and environmental interactions, such as phase separation and the formation of secondary organic aerosols. However, directly measuring particles pH remains a challenge, necessitating urgent exploration. This study utilizes optical tweezers to investigate and compare methods for measuring pH of particle. Initial steps involved preparing a solution with sodium carbonate and sodium bicarbonate system, followed by measurement of ion concentration calibration curves for HCO3- and CO32-. Droplets were then generated using an atomizer and prepared solution. A single-beam Gaussian optical tweezers captured individual particles and obtained their Raman spectra in conjunction with a Raman spectrometer. Four methods—Henderson-Hasselbalch equation, Debye-Hückel theory, specific ion interaction theory, and thermodynamic model—were then applied to calculate pH values based on HCO3-/CO32- conjugate acid/base pairs and ion concentration calibration curves. The experimental results demonstrated small error in each calculated pH value. Additionally, the study revealed a rapid decomposition process of HCO3- in droplets, possibly attributed to the high specific surface area of small droplets or the absence of CO2 in the optical tweezers chamber. The study also monitored the evolution of pH values in sodium bicarbonate particles over time. Furthermore, the study investigated difference in pH values calculated by the four calculation methods under different ion strengths and pH values. The study also measured the pH value of sodium carbonate particles in relation to relative humidity. Overall, the experimental outcomes were reasonable and validated the capability of optical tweezers in probing the pH of atmospheric particles, offering insights into the applicable conditions of different methods and directions for refining thermodynamic models. 
Magnetotelluric Evidence for the Paleo-Subduction Polarity and Recycled Carbonates within the Beishan Orogen, Southern Central Asian Orogenic Belt 
Authors: Zhou Lishui , Zhang Letian , Jin Sheng
Published: March 2024

The Beishan Orogen, located in the southernmost part of the Central Asian Orogenic Belt, comprises ophiolitic complexes, passive-margin strata, arc assemblages, and Precambrian basement rocks, recording oceanic subduction, accretion of oceanic materials onto continental margins, and continental-arc collision. However, debates surrounding its origin and evolution persist, attributed in part to the absence of high-resolution geophysical data, leading to varying interpretations in tectonic evolution models regarding the involved terranes and paleo-subduction polarity (Li et al., 2023). In this study, we present an electrical resistivity model of the crust and uppermost mantle in the Beishan Orogen from magnetotelluric (MT) data. The resistivity model suggests an overall resistive upper crust, with conductive features indicating paleo-suture zones and tectonic boundaries. The high resistivity lithosphere beneath Niujuanzi indicates both north- and southward subduction of the Hongliuhe-Xichangjing Ocean, potentially unveiling remnants of a cold fossil oceanic lithosphere. Conductors in mantle wedges on both sides of the high resistivity body are inferred to result from recycled carbonates introduced deep into the Earth through oceanic subduction, which is substantiated by recent laboratory measurements (Jing et al., 2023). These measurements demonstrate that even unmelted carbonates can enhance electrical conductivity through cation exchange reactions with silicates in the lower crust and uppermost mantle.*This research is funded by the National Natural Science Foundation of China (42074089, 41774087, 41404060).ReferenceJing, C., Hu, H., Dai, L., Sun, W., Wang, M., Hu, Z., 2023. Recycled carbonates elevate the electrical conductivity of deeply subducting eclogite in the Earth’s interior. Commun Earth Environ 4, 276. https://doi.org/10.1038/s43247-023-00936-wLi, J., Wu, C., Chen, X., Zuza, A.V., Haproff, P.J., Yin, A., Shao, Z., 2023. Tectonic evolution of the Beishan orogen in central Asia: Subduction, accretion, and continent-continent collision during the closure of the Paleo-Asian Ocean. GSA Bulletin 135, 819–851. https://doi.org/10.1130/B36451.