bluuebunny/crossref_metadata_2025 huggingface dataset:
Resolving nitrogen gaseous pathways in the atmosphere-plant-microbial-soil continuum in the NOAA/GFDL Earth System Modeling Framework
Authors: Beaudor Maureen , Shevliakova Elena , Malyshev Sergey , Lee Minjin
Published: March 2024

Representing plant-microbe-soil organic matter interactions and their coupling with land surface processes are critical to understanding of ecosystem responses to climate change. More specifically, microbes play an important role in the nitrogen (N) cycle by providing acquisition pathways for plants and overcoming N limitation through mycorrhizal symbiosis and bacterial fixation. Even though biological nitrogen fixation acts as a primary N source for the organisms, ecosystem N availability is still strongly affected by N losses, including atmospheric volatilization.One of the major challenges to accurately representing N availability in Earth System Models (ESM) is the representation of the atmospheric losses that are not necessarily controlled by the organisms. For instance, the conversion of soil ammonium into gaseous ammonia (i.e., volatilization) is driven by ambient environmental conditions and not directly controlled by the biological demand of plants and soil microbes. Thus, rapid losses of N via volatilization (e.g., after precipitation events) could induce feedback on soil microbial activity and plant growth by impeding biological assimilation.Even though the representation of ammonia emissions is progressively integrated into ESMs, the focus has been mainly on parameterizing losses from agricultural or managed ecosystems. However, ammonia volatilization from natural soils occurs worldwide and can reach 9 TgN/yr, a non-negligible source, especially in alkaline drylands. Up to now, no proper representation of emissions of ammonia, applicable to unmanaged lands, has been included in ESMs and challenged by observations. In the future, these emissions are likely to follow the rising trends of nitrogen deposition and increasing precipitation due to climate change.Here we describe a mechanistic parameterization of ammonia emissions in natural ecosystems with explicit treatment of microbes and vegetation dynamics in the fully integrated terrestrial component of the GFDL ESM, LM4.2-GIMICS-N. We apply observational constraints, including measurements of soil 15N isotope and estimates of nitrogen fluxes (BNF, nitrification, mineralization, and ammonia exchange) at different sites to reduce uncertainty in the model simulations. Finally, we examine the main drivers of ammonia volatilization across various ecosystems by considering aridity, soil pH, and nitrogen deposition as well as the key environmental conditions such as precipitation, temperature, and soil moisture.
Recent methane surges reveal heightened emissions from tropical inundated areas
Authors: Lin Xin , Peng Shushi , Ciais Philippe , Hauglustaine Didier , Lan Xin , Liu Gang , Ramonet Michel , Xi Yi , Yin Yi , Zhang Zhen ,   Coauthors
Published: March 2024

Record breaking atmospheric methane growth rates were observed in 2020 and 2021 (15.2±0.4 and 17.6±0.5 ppb yr-1), reaching their highest level since the commencement of ground-based observations in the early 1980s. Here we use an ensemble of atmospheric inversions informed by surface or satellite methane concentration observations to infer emission changes during these two years relative to 2019. We found a global increase of methane emissions of 20.3±9.9 Tg CH4 in 2020 and 24.8±3.1 Tg CH4 in 2021. The emission rise was dominated by tropical and boreal regions with inundated areas, as a result of elevated groundwater table. Strong, synchronous, and persistent emission increases occurred in regions such as the Niger River basin, the Congo basin, the Sudd swamp, the Ganges floodplains and Southeast Asian deltas and the Hudson Bay lowlands. These regions alone contributed about 70% and 60% of the net global increases in 2020 and 2021, respectively. Comparing our top-down estimates with simulation of wetland emissions by biogeochemical models, we find that the bottom-up models significantly underestimate the intra- and inter-annual variability of methane sources from tropical inundated areas. This discrepancy likely arises from the models’ limitations in accurately representing the dynamics of tropical wetland extents and the response of methane emissions to environmental changes. Our findings demonstrate the critical role of tropical inundated areas in the recent surge of methane emissions and highlight the value of integrating multiple data streams and modeling tools to better constrain tropical wetland emissions.
Sequence stratigraphy based on high-resolution seismic profiles in the late Pleistocene-Holocene deposits of the eastern Yellow Sea
Authors: Yoo Dong-Geun , Hong Seok-Hwi , Lee Gwang-Soo , Kim Gil-Young , Choi Yunsoo
Published: March 2024

The late Quaternary stratigraphy and depositional history at the eastern Yellow Sea shelf was studied using a dense network of high-resolution, single-channel seismic reflection profiles and sediment data. The shelf deposits in this area consists of six seismic units formed since the LGM. During the LGM, the study area was completely exposed, resulting in subaerial erosion associated with paleo-channel incision by the Huanghe and Korean Rivers. As the shelf was flooded, the incised channels were backfilled fluvial or coastal sediments, forming incised channel-fill deposits (SU1). The paleo-river may have supplied abundant terrigenous sediments to the study area around the paleo-river mouth and adjacent area. These sediments were trapped within the paleo-estuary and formed SU2, regarded as an estuarine deposit. Two types of serial sand ridges (SU3 and SU5) which correspond to transgressive deposits developed. SU3 on the southern part (80~110 m deep) is regarded as a moribund-type mainly formed during the early to middle stage of transgression. These are thought to have ceased growing and remobilizing. In contrast, SU5 (occurring 30~50 m deep off the Korean Peninsula) is generally regarded as active sand ridges deposited during the late stage of transgression and is partly modified by modern tidal currents. As the transgression continued, the near-surface sediments were reworked and redistributed by shelf erosion, resulting in a thin veneer of transgressive sands (SU4). The uppermost unit (SU6) formed the Heuksan Mud Belt (HMB), which is one of the most prominent mud deposits in the Yellow Sea. The lower part of the HMD corresponds to shelf-mud deposited during the late stage of transgression, whereas the upper part consists of a recent shelf-delta developed after the highstand sea level at about 7 ka BP. 
Human adaptation to diverse biomes over the past 3 million years
Authors: Zeller Elke , Timmermann Axel , Yun Kyung-Sook , Raia Pasquale , Stein Karl , Ruan Jiaoyang
Published: March 2024

We identify past human habitat preferences over time to investigate the role of vegetation and ecosystem diversity on hominin adaptation and migration. Using a transient 3-million-year earth system-biome model simulation and an extensive hominin fossil and archaeological database we distinguish in what habitat previous Hominin lived. Our analysis shows that early African hominins predominantly lived in open environments such as grassland and dry shrubland. Hominins adapted to a broader range of biomes by migrating into Eurasia. By linking the location and age of hominin sites with corresponding simulated regional biomes, we also find a preference for spatially diverse environments. Suggesting our ancestors actively sought out mosaic landscapes.
Evaluating coastal atmospheric properties using UAS during TRACER
Authors: de Boer Gijs , Lappin Francesca , Butterworth Brian , Klein Petra , Quint Daphne , Calmer Radiance , Asher Elizabeth , Argrow Brian
Published: March 2024

The Tracking Aerosol Convection Interactions Experiment (TRACER) project deployed a variety of observing systems to the greater Houston area in 2021/2022 to help improve our understanding of the interplay between the urban environment, aerosol particles, and coastal circulations and their combined influence on the development of convection and precipitation.  With approximately 40% of the planet’s population living in coastal regions, extreme precipitation events in these areas can have significant impact and result in significant damage and losses.  In the Houston urban metroplex many of these impacts are amplified by the generally low-lying terrain, which contributes to significant regional flooding events under heavy precipitation. As part of TRACER, teams from the University of Colorado Boulder and University of Oklahoma deployed small uncrewed aircraft systems (UAS) to areas between the Gulf of Mexico and Houston.  Collecting data on thermodynamic, kinematic, and aerosol properties in the lower atmosphere, the measurements from these platforms provide unique perspectives on the vertical and horizontal variability in key parameters.  During this presentation, we will provide an overview of the sampling strategies employed during TRACER and the platforms used to collect airborne data, the types of measurements collected, and initial results on aerosol conditions and sea breeze properties from the deployment.  We will additionally provide broader context by combining these data with measurements from the US Department of Energy’s 2nd Atmospheric Radiation Measurement (ARM) program Mobile Facility (AMF-2), which was deployed to the region for the TRACER campaign.  
Study of ionospheric variations from a global network of VLF antennas
Authors: Galopeau Patrick , Boudjada Mohammed , Eichelberger Hans , Maxworth Ashanthi , Biagi Pier , Schwingenschuh Konrad
Published: March 2024

We present a system which records electromagnetic signals, in the Very Low Frequency (VLF: 3 kHz – 30 kHz) and Low Frequency (LF: 30 kHz – 300 kHz) range, 24 x 7 x 365, with the goal of identifying ionospheric variations. An individual system consists of a monopole antenna, a pre-amplifier, a power supply, a central computer, a GPS unit, and a recording device. Several receivers will be implemented around the globe in a network. The first implementation of the system was done in Graz (Austria), the second one will be in Guyancourt (France), a third one in Réunion (France) and a fourth one in Moratuwa (Sri Lanka). Each reception device will allow a continuous daily monitoring of transmitter signals in the VLF and LF frequency bands. This network will be devoted to the study of ionospheric variations, in particular, those linked to the solar activity, but also those associated with seismic activity with the purpose to identify electromagnetic earthquake precursors.
Navigating Water Resource Management: A Forecasting Framework for Interannual Drought Projections
Authors: Jiang Ze , Kibria Golam , Sharma Ashish
Published: March 2024

Can CMIP6 decadal projections be effective for multi-decadal water resources planning? This is the underlying question that motivates the present research, investigating what are the key deficiencies that limit their direct use for applications, and whether cleverly formulated mathematical alternatives can be used as effective postprocessors. This study focuses on the development of a robust framework for predicting droughts over interannual to decadal scales to enhance water resource management. The proposed framework utilizes the Wavelet System Prediction (WASP) methodology, which refines the spectral attributes inherent to climate indices to improve the skill of drought forecasts. Further improvement in forecasting capability is achieved through the Hierarchical Linear Combination (HLC) logic, which incorporates forecasts from ten climate indices. These indices, including ENSO-related sea surface temperature anomalies and other climate drivers closely linked to Australian rainfall, are derived from decadal predictions of the Decadal Climate Prediction Project (DCPP). The results of projected drought indices across various scales in Australia demonstrate the substantial potential of the integrated HLC-WASP framework to significantly improve the forecast skills of medium to long-term drought scenarios. This advancement enables the water industry to adapt their strategic plans and optimize reservoir operations effectively. By providing more reliable near-term projections of water availability, this research contributes to effective water resource management, facilitating informed decision-making for water allocation and conservation initiatives.
Soil moisture downscaling based on physics-based hydrological simulations: a downscaling playground and a novel high-resolution downscaling product for the continental USA
Authors: Leonarduzzi Elena , Maxwell Reed M.
Published: March 2024

High-resolution soil moisture is key for a wide range of applications such as water resources management, agriculture, and natural hazard monitoring and prediction. In the last few decades, the prominent approach for deriving high resolution soil moisture fields over large areas has been downscaling of satellite observations. These approaches, which are mainly machine learning based, use the coarse resolution estimate from the satellite, combine it with other variables which impact soil moisture distribution (e.g., landcover, topography, soil characteristics) and/or other remote sensed products with higher spatial resolution, and use the in-situ soil moisture observations for training/testing.Here, we follow a different approach, which takes advantage of physics-based hydrological simulations. First, we create a downscaling playground by using historical simulations of the hydrological model ParFlow-CLM over the continental USA (CONUS). We use the 1 km2 run as our high-resolution estimate, and an upscaled version (averages over 10x10 km2 gridcells) as representative of the coarse resolution estimate. By doing this, we remove two of the biggest issues when downscaling soil moisture: first, we know there’s a perfect match between high- and low-resolution soil moisture and second, we can train and test the model freely over the entire domain, as information is available for every gridcell, without being constrained by the number/locations of in-situ stations. In terms of downscaling approach, we use a random forest model, trained on coarse resolution soil moisture, drainage area, slope, elevation, hydraulic conductivity, porosity, and landcover. We carry out several experiments changing the locations and timing of both the training and testing sets. These experiments allow us, for example, to test whether the in-situ stations available are adequate in number and representative of the entire domain for reliable downscaled products.Finally, we take advantage of this playground to develop a new downscaling product. We train the same random forest model, but over the CONUS domain, using all gridcells. This results into a model that has learned the spatial scaling of soil moisture between the two resolutions and can predict the 1 km2 over CONUS, fed by a 10x10 km2 estimate in addition to static predictors. We then use the model in a predictive mode, feeding it the coarse resolution estimate from Soil Moisture Active Passive (SMAP) satellite, creating a high-resolution (1 km2) version of SMAP soil moisture.
Assessment and comparison of crop growth models for estimating wheat production in a semi-arid region of Morocco
Authors: Kaissi Oumaima , Er-raki Salah , Bouras Elhoussaine , Belaqziz Salwa , Chehbouni Abdelghani
Published: March 2024

Faced with growing food security challenges influenced by global factors such as population growth, climate change, and soil erosion, the need for sustainable agricultural practices is particularly relevant in Africa. In Morocco, wheat is the most dominant crop, but its production is highly dependent on rainfall. In this research, we evaluate several crop growth models, including AquaCrop, among others, focusing on their ability to effectively improve crop production predictions and yield gap analysis in Morocco. This evaluation is essential to develop adaptive agricultural practices that can mitigate the adverse effects of climate change on crop yields. This study employs AquaCrop-OSPy (ACOSP), an open-source Python version of the AquaCrop model, to simulate various indicators of crop growth such as canopy cover (CC), actual evapotranspiration (ETcact), biomass, and grain yield (GY) for wheat under drip irrigation in the semi-arid Chichaoua region of Marrakech in Morocco. The model was first calibrated by using the field data collected over two wheat fields during the 2016/2017 cropping season. Key parameters affecting CC, ETcact, biomass, and GY were calibrated by comparing field measurements with the model outputs. Then, model validation was carried out on the same fields but during the 2017/2018 cropping season. The results demonstrated that ACOSP effectively simulates CC, ETcact, biomass, and GY across two growing seasons. The comparative analysis between observed and simulated parameters yielded the following average values: for CC, R²=95%, RMSE=8.5%, and MSE=1.1%; for ETcact, R²=76%, RMSE=0.61 mm/day, and MSE=0.40 mm/day; and biomass, R²=87%, RMSE=0.22 t/ha, and MSE=0.05 t/ha during the calibration season. GY recorded was 3.87 t/ha. In the validation season, the model achieved similar accuracy for CC R²=95%, RMSE=8.0%, MSE=1.0 %; and biomass R²=91%, RMSE=0.15 t/ha, MSE=0.05 t/ha; with a GY of 3.29 t/ha. These results confirm the model's reliability in simulating key growth parameters of wheat in a semi-arid environment. Two main aspects are addressed through this study: firstly, to provide valuable information for agricultural policy and decision-making in Morocco, and secondly, to enrich the international conversation on sustainable agricultural practices, particularly in arid and semi-arid regions. Leveraging the findings of efficient simulation of wheat growth and production using the ACOSP model, this research provides a solid basis for local, national, and international key actors in developing robust strategies to improve wheat production, thus enhancing the sustainability and resilience of Moroccan agriculture.
Unveiling the Mysteries of Multiscale Magnetotail Dynamics with the CINEMA Constellation
Authors: Ukhorskiy Sasha , Millan Robyn ,   CINEMA Science Team
Published: March 2024

Planetary magnetospheres are among the most dynamic and complex systems studied in heliophysics. Driven by their stellar environment and internal sources (e.g., planetary rotation or moons), these vast reservoirs of magnetic energy exhibit a range of dynamical states. Energy circulation (convection) through the system can be steady or explosive, triggering fast plasma flows, global current systems, and spectacular auroral displays. Understanding the response of magnetospheres to their stellar environment is essential for understanding the nature of our home in space, a key heliophysics goal. In Earth’s solar wind–driven magnetosphere, the magnetotail is a key region through which energy is circulated. How the magnetotail maintains steady convection, and when and how it decides to explosively release stored energy, are major unsolved mysteries of space physics. A significant challenge is the intrinsically multiscale nature of magnetotail convection, which is difficult to capture with the sparse measurements available so far. The CINEMA (Cross-Scale INvestigation of Earth’s Magnetotail and Aurora) SMEX Phase A Mission Concept will provide a new cross-scale view of the magnetotail, revealing its large-scale configuration and its influence on dynamics at smaller scales. With a constellation of 9 spacecraft in low-earth orbit all equipped with a full complement of high-resolution energetic particle sensor, auroral imagers, and magnetometers, CINEMA will capture the plasmasheet structure and evolution key for unveiling the mysteries of multiscale magnetospheric convection.  
Volcanic and thermogenic emissions from the North Atlantic Igneous Province: Insights from melt and fluid inclusions
Authors: Jones Stephen , Capriolo Manfredo , Muirhead David , Tegner Christian
Published: March 2024

Throughout the Phanerozoic, temporal coincidence between Large Igneous Provinces (LIPs) and climate perturbations points to a potential causality via volcanic and thermogenic emissions. The best documented example of this association consists in the North Atlantic Igneous Province (NAIP) and the Paleocene–Eocene Thermal Maximum (PETM), which represents the most recent natural analogue for anthropogenic greenhouse gas emissions flux [1]. The NAIP extends from Greenland to the Scandinavian Peninsula and the British Isles, but the East Greenland margin preserves one of the most studied magmatic systems: the Skaergaard intrusion and its overlying 6-8 km thick lava pile, close to the centre of the province [2]. Melt and fluid inclusions within intrusive and effusive rock samples from East Greenland were screened and selected to investigate their volatile content by confocal Raman microspectroscopy. In the effusive rock samples, phenocrysts of olivine, clinopyroxene and sometimes plagioclase host primary melt inclusions containing gas bubbles. On the contrary, in the intrusive rock samples, most of primary melt inclusions within olivine crystals do not contain any gas bubble. However, in these rock samples, quartz often occurs as interstitial subhedral crystals or forms graphic textures with alkali feldspar, and hosts abundant multiphase (i.e., gaseous ± liquid ± solid phases) fluid inclusions. In general, the investigation of volatile species preserved by melt and fluid inclusions within magmatic minerals allows the reconstruction of volcanic and thermogenic emissions from LIPs [3; 4]. Here, we present preliminary data of this ongoing project that aims to constrain the role of volatiles from the NAIP in driving the synchronous PETM. [1] Jones et al. (2019), Nat. Commun. 10, 5547.[2] Larsen & Tegner (2006), Lithos 92, 181–197.[3] Capriolo et al. (2020), Nat. Commun. 11, 1670.[4] Capriolo et al. (2021), Nat. Commun. 12, 5534.
Increasing water footprints of flex crops
Authors: Mialyk Oleksandr , Berger Markus , J. Booij Martijn
Published: March 2024

Flex crops—crops with multiple end-uses that can be flexibly interchanged—play an important role in our society. Due to high nutritional and energy contents, they became widely used in various industries, providing food, animal feed, biofuels, and other chemical components. However, a limited number of studies exists on the environmental pressures of such crops, specifically concerning water resources.Here, we aim to quantify the water footprints of main flex crops—namely maize, oil palm, soya beans, sugar cane, coconut, cassava, rape seed, and sunflower—using a recently published database on gridded water footprints of the world’s major crops in the 1990–2019 period. Our study reveals three key developments:All flex crops experienced large water-productivity gains in response to increasing crop yields (less water is needed per tonne).
The global water footprint of flex crops has increased by more than one trillion cubic metres as productivity gains were insufficient to meet rapidly growing demand.
The production of flex crops has been concentrating around main exporting regions, most notably in Latin America and South-eastern Asia.
As demand keeps increasing, this raises a need for further research addressing the sustainability of flex crops. In particular, regarding the potential links to green and blue water scarcity, exposure of global supply chains to socio-economic and climatic risks, and the role of flex crops in our society.
Anoxia in the Permian Irati-Whitehill Ocean of southern Gondwana: A possible link with uprising of the Cape and San Rafael mountain belts
Authors: Caxito Fabricio , Sperling Erik , Bastos Lucas , Pereira Egberto
Published: March 2024

The Permian section of the Paraná-Etendeka basin is represented by the Palermo and Irati formations, comprising a shallow sea that occupied ca. 5 million km2 of southern Gondwana before completely drying out around 277 million years ago (Irati-Whitehill ocean). This is broadly coincident with the uprising of the Cape Fold Belt of southern Africa and the San Rafael orogeny of the paleo-Pacific margin of South America, leading to the interpretation that basin restriction and the major ecosystem changes that followed were ultimately caused by uprising of mountainous domains surrounding the shallow sea. We combine new iron speciation, organic carbon isotope and trace element data with previous biomarker, organic carbon and nitrogen isotope data to unravel the biogeochemical and redox changes during this transition from an open marine realm to a restricted setting, and to test the hypothesis of external controls on the biogeochemical cycles of southern Gondwana. Mudstones and shales of the Palermo Formation yielded FeHR/FeT around or below 0.2, suggesting oxic bottom water conditions, reinforced by muted redox-sensitive element (RSE) concentrations and overall low Total Organic Carbon (TOC) contents, with δ13Corg around -25‰. Black shales of the overlying Irati Formation, on the other hand, record an abrupt shift to anoxic conditions, with FeHR/FeT between 0.3 and 0.9, representing mostly ferruginous conditions with sporadic euxinic incursions (FePy/FeHR > 0.8), higher concentrations of RSE such as Mo, higher TOC contents and d13Corg rapidly oscillating from ca. -29 up to ca. -19‰. The euxinic intervals are associated with the Assistência Member, containing tephra layers dated at 277 Ma and thus coeval to the Cape and San Rafael orogenies. Our results reinforce the hypothesis of mountain belt formation as the main external driver of biogeochemical changes, leading to toxic conditions for complex life forms in the Permian internal basins and to the accumulation of important organic-rich source rocks in the shallow seas of southern Gondwana.
Assessment of the spatial distribution of soil erosion using the RUSLE model and field survey study - A case study of Beas Valley, Kullu, India, Western Himalaya 
Authors: Maurya Suraj , Singh Vartika , Chand Kesar , Mishra Prabudh
Published: March 2024

Soil erosion, a global challenge with profound consequences, impacts soil nutrient depletion, land degradation, agricultural productivity, runoff, and geological hazards. Our study assesses soil erosion and land use changes in the Beas Valley, Kullu, Himachal Pradesh, situated in the Western Himalayas. Employing diverse datasets and a comprehensive methodology, we scrutinize the intricate interactions of climate, soil, topography, and land use to comprehend and mitigate soil erosion risks. Data sources include rainfall data from the Climate Research Unit at the University of East Anglia, soil data from the Food and Agriculture Organization, Digital Elevation Model (DEM) data from the Shuttle Radar Topography Mission, and Landsat satellite imagery. We utilize the Revised Universal Soil Loss Equation (RUSLE) for soil erosion assessment, which includes factors like erosivity (R-factor), erodibility (K-factor), slope and flow accumulation (LS-factor), vegetation cover (C-factor), and conservation practices (P-factor).To bolster the credibility of our findings, we complement our methodology with field observations and interviews. These on-ground assessments and stakeholder insights provide practical context and verification for our research. This interdisciplinary approach yields crucial insights into soil erosion and land use changes in the Beas Valley, enriching our understanding of soil erosion in this fragile Himalayan ecosystem. Our findings offer vital support for informed land management decisions and conservation efforts. Keywords: Soil erosion assessment, Himalayan, RUSLE, GIS and Remote Sensing
Towards 3D SPM monitoring in the North Sea using multibeam sonar
Authors: Praet Nore , Urban Peter , Roche Marc , Mortelmans Jonas , Lagaisse Rune , Vandorpe Thomas
Published: March 2024

Monitoring suspended particulate matter (SPM) in coastal areas is essential for research, management and protection of coastal ecosystems. In the Belgian part of the North Sea, the dynamic nature of SPM variability and the increasing human activities (offshore windmill parks, dredging and dumping) call for 3D monitoring of these natural and human-induced SPM changes.Multibeam echosounders (MBES) provide, in addition to bathymetry and seafloor backscatter data, a 3D dataset of acoustic measurements in the water column, which can be used to monitor SPM in coastal waters. Although MBES water column data are commonly used by fisheries and gas seepage research, only a handful of studies focus on the quantification of SPM in the water column.During the Timbers project, we developed a novel methodology to convert MBES water column data into 3D SPM maps. In contrast to most studies that deploy the MBES from stations, we quantified SPM using MBES from a sailing vessel. Simultaneous optical and acoustic measurements were collected during ship transects to yield an empirical relation using linear regression modeling. This relationship was then used to convert the acoustic measurements into a 3D grid that displays the mass concentration of SPM. The large spatial coverage of these SPM maps allows us to observe phenomena in the water column that otherwise would be missed by traditional monitoring approaches. Furthermore, several valuable lessons were learned. In particular, the interpretation of the acoustic signal is not straightforward, which makes it difficult to distinguish between different types of scatterers (sediment, plankton, flocs, bubbles, fish, etc.) captured by the MBES. Hence, additional research efforts focusing on discriminating scatterers in the water column are needed to unlock the full monitoring potential of MBES water column data.In the ongoing Turbeams project, we are exploring multi-frequency approaches to differentiate between various scatterers and their wide spectrum of sizes. Additionally, we are applying imaging tools on collected water samples and we are using underwater cameras that capture particles in their natural environment. These improvements will help to move towards operational use of MBES as a common tool for SPM monitoring in the future.
Towards a Global Assessment of Bar Push Versus Bank Pull using Remote Sensing and Cloud Computing.
Authors: Nagel Gustavo , Darby Stephen , Leyland Julian
Published: March 2024

Rivers and floodplains are hotspots of biodiversity that support a large and growing number of people with food, water, nutrients, and transportation. Within these floodplains, the dynamic interplay of erosion on the outer banks and sedimentation on the inner banks propels lateral channel migration, resulting in the creation of intricate and sinuous meandering river landscapes. A key question in river meandering research concerns the ongoing debate regarding the primary driver of lateral river migration. Is it initiated by outer-bank erosion, leading to localized inner-bank deposition (the process known as ‘bank pull’), or is it inner sedimentation that initially diverts the flow, subsequently triggering outer-bank erosion (‘bar push’)? This study introduces an innovative methodology that combines extensive time series analysis of remote sensing imagery with cloud computing to discern the prevalence of bar push versus bank pull across vast sections of the global river network. The methodology involves analyzing each image to pinpoint the precise timing of pixels undergoing erosion and/or sedimentation. For each river bend, we compare the years in which the outer bank undergoes erosion with the years in which the inner bank experiences sedimentation, thereby determining the predominant process—erosion and bank pull, or sedimentation and bar push. Additionally, we explore whether these processes change over time and whether they are correlated with factors such as river sediment load, bank vegetation, river curvature, and other relevant physiographic metrics. By extending this methodology to diverse rivers worldwide, we systematically test the bar push versus bank pull theories in a variety of real environmental settings. This unprecedented, large-scale analysis advances our understanding of meandering rivers and their complex dynamics.
Skill of the ECMWF SEAS5 ensemble prediction system in streamflow and rice yield forecasting for Mainland Southeast Asia 
Authors: Wanthanaporn Ubolya , Hutjes Ronald , Supit Iwan
Published: March 2024

The potential use of European Centre for Medium-Range Weather Forecast (ECMWF) ensemble prediction system SEAS5 over Mainland Southeast Asia was evaluated. The evaluation spans 30 years (1985–2014), examining SEAS5's skill in predicting temperature and precipitation. Subsequently, SEAS5 data was used to force the Variable Infiltration Capacity (VIC) hydrological model for runoff and streamflow forecasts, as well as the WOrld FOod Studies (WOFOST) crop model for rice production forecasts. These hydrological and agricultural results were compared against the WFDE5-driven reanalysis using verification skill metrics at grid cells for each month. Furthermore, the hydrological results were compared against observed station data. The reanalysis of rice yield was also compared against FAO observations, but proved inconclusive. The findings reveal promising predictive capabilities for temperature beyond a 2-month forecast, while the skill of precipitation and streamflow forecasts extend to a 1-month. Noteworthy, strong seasonal and regional dependence occurs, with high forecast skills during the pre-monsoon (April–May) and post-monsoon (October–November). Year–to–year precipitation tercile plots highlight skill in predicting the anomalous seasonal conditions associated with ENSO. The significant streamflow skill at each initiation month and lead time corresponds to the forecasting skill of meteorological variables. Nevertheless, it is important to note that the skill level of discharge and runoff forecasts is generally lower compared to the skill in temperature and precipitation. For the rice prediction, SEAS5 exhibits high performance at the beginning of the rainy season, where strong seasonal climate predictions are observed. The model shows the ability to capture anomalous rice yields and consistent accuracy throughout a 1-month to 3-month forecast. However, limitations in skill are evident when rice planting times are delayed by one or two months during the rainy season, as well as when planting in the dry season. SEAS5 shows useful skills that can potentially be used for hydrological and agricultural anticipatory management. The results could already support an initial step to come to potential anticipatory (agro-)hydrological management and could be utilised as an input for an early warning system in various sectors.
Assimilation of Written Climate and Weather Records into Paleoclimate Reanalysis using a Non-Linear Forward Model
Authors: Cho Patrick , Müller Marc , Bolster Diogo
Published: March 2024

Recent reanalysis products offer unprecedented insights on past climates, but the paleoclimatic proxies that they assimilate are unevenly distributed in space leading to substantial simulation uncertainties over certain regions. In that context, written climate and weather records -- or docu proxies --  covering the past 2,000 years offer promising insights to complement natural proxies. However, docu proxies are also subject to a range of biases and error sources, for instance related to the cultural, technological background of the author and the prevailing need to convert qualitative observation to quantitative data assimilation input. These challenges require careful consideration when assimilating docu proxy into climate products, many of which employ a Bayesian Hierarchical approach with a forward model intended to translate climate models' initial estimates into a space that is compatible with the (natural or docu) proxy. Currently, docu proxy assimilation uses multivariate linear models for this transition, but the presence of perception biases within docu proxies suggests that linearity assumptions may not be suitable. To address this, we propose a non-linear forward model that better replicates docu proxy characteristics, aiming for more accurate assimilation. Leveraging the DOCUCLIM database and Last Millennium Reanalysis, we assess the efficacy of this non-linear approach.
Investigating the influence of soil organic carbon on pore structure within aggregates a comparative study of Ultisols and Cambisols in China
Authors: Liu Jingjing , Tian Yu , Lu Shenggao
Published: March 2024

Soil pore structure, dictated by factors such as porosity, size distribution, and geometry, is crucial for various soil processes and is significantly influenced by soil organic carbon (SOC). As the primary architect of pore geometry within soil aggregates, SOC plays a vital role in determining soil functionality and ecosystem services, yet traditional in-situ analysis methods have fallen short in accurately depicting its intricate distribution. The study employed a two-fold approach to analyze soil structure: a hydrogen peroxide fogging system was used to selectively remove organic carbon from soil aggregates, followed by synchrotron radiation micro-computed tomography (SR-μCT) for in-depth three-dimensional imaging. The results revealed that hydrogen peroxide treatment variably reduced organic carbon in soil aggregates, with Cambisol showing a higher removal efficiency (68-79%) compared to Ultisol (42-47%). The data highlighted the transformation of smaller pores and an increase in larger pore spaces following organic carbon removal, with Cambisol aggregates experiencing the most substantial alterations in pore structures. The impact of organic carbon on the shaping of pore structure within soil aggregates was profound and varied distinctly between the two studied soils—Ultisol and Cambisol. In Ultisol, the organic carbon, initially minimal, played a subtle role in pore structure formation, leading to limited changes post-removal, which suggested a structural resilience possibly due to its inherent mineralogy and physicochemical characteristics. In contrast, Cambisol, with higher initial organic carbon content, showed dramatic alterations in pore structure upon organic carbon removal. This indicated a more critical role of organic carbon in maintaining pore space configurations, with significant increases in larger pore spaces and a decrease in smaller, disconnected pores. These changes highlighted the organic carbon’s crucial function in not only sustaining pore integrity but also in facilitating the complex soil functions such as water retention and root penetration.
US Corn Belt enhances regional precipitation recycling
Authors: Zhang Zhe , He Cenlin , Chen Fei , Miguez-Macho Gonzalo , Liu Changhai , Rasmussen Roy
Published: March 2024

Precipitation recycling, characterized by the contribution of local evapotranspiration (ET) to local precipitation, is a critical component of theregional water cycle. In the US Corn Belt, vast croplands and irrigation applications have markedly modified surface energy and water balance, which inturn modulates precipitation recycling. However, previous studies often neglected the complex hydrological and crop physiological processes at land surface with an oversimplified assumption. In this study, we aim to understand the precipitation recycling in the US Corn Belt with explicit shallow groundwater dynamics, crop growth, and irrigation processes in the WRF model, with the water vapor tracer (WVT) capability to track ET directly from croplands. We found that the croplands exhibit a strong cooling effect on air temperatures and increasing summer precipitation. The increase in precipitation can be attributed to enhanced precipitation recycling, ranging from 11 to 22%, and much stronger seasonality during summer growing seasons. Such cooling effect and contribution to precipitation recycling is more significant in a drought year compared to normal and wet years, depending on both large-scale moisture advection and local moisture source. Our results have important implications to modeling ecohydrology and agricultural management in the Earth system, understanding precipitation recycling in the entire water cycle and designing sustainable water resource governance.
Pining for an Anomaly: Exploration and environmental assessments using regional and local scale biogeochemical patterns in the Cobar Region, Australia.
Authors: Schifano Joseph , Cohen David , Rutherford Neil
Published: March 2024

In regional or local scale geochemical mapping, the choice of sampling media and analytical methods will be influenced by the source, form, mobility and spatial distribution of elements being mapped. For environmental monitoring and mineral exploration there are potential advantages in using plant organs rather than regolith materials as the sampling media, including the capacity of plants to sample large volumes of underlying regolith and the averaging of their biogeochemical composition over timeframes extending from months to years. The limited use of plant organs in geochemical mapping relates partly to perceived complicating factors such as variability between plant species, seasonal variability in some plant organs and analytical costs. Needle samples from over 4,000 cypress pines (C. glaucophylla) in the highly mineralised Cobar Basin in central New South Wales have been analysed by both ICPMS and pXRF. The study spanned regional mapping using samples collected adjacent to roads and tracks, and detailed grids and traverses across 36 mineral prospects and deposits. For various major and trace elements, there is strong correlation between results obtained by total digestion ICPMS and by portable XRF, including direct pXRF analysis of unprocessed samples in the field.There are distinct lithological influences on variation in the background values for various elements, including Au and Pb, noting that the majority of mineral deposits are structurally hosted within the Devonian sandstone and siltstones regionally intruded by felsic intrusives. There is an extensive zone of elevated base and precious metal values in the needles between the Peak Au mine site and the city of Cobar which was the focus of mineral processing for many decades. Highly elevated values for Ag, Au, Pb, Zn, Ni, Co, W and/or REE occur above known mineral deposits, depending on deposit style, and commonly display more consistent geochemical spatial patterns than in regolith samples. Pines in general typically restrict uptake of Cu in the needles to within the range of 3–12 ppm due to its function as an important trace nutrient.
Astronomy from the Moon: From Exoplanets to Cosmology in Visible Light
Authors: Schneider Jean
Published: March 2024

I look at what astronomy from the Moon might be like in the visible over the next few decades.The Moon offers the possibility of installing large telescopes or interferometers with instruments larger than those on orbiting telescopes. I first present examples of ambitious science cases, in particular ideas that cannot be implemented from Earth. I discuss also the issues which I telescope will encounter underlunar conditions. After a general review of observational approaches, from photometry to high contrast and high angular resolution imaging, I propose as a first step a 1-metre-class precursor and explore what science can be done with it.
Impact of the Indian Ocean Basin Mode on Tropical Cyclone Genesis in the North Indian and Western North Pacific Oceans
Authors: Widana Arachchige Erandani Lakshani , Zhou Wen , C. L. Chan Johnny , Wang Xuan
Published: March 2024

This study investigates the diverse influence of the Indian Ocean Basin Mode (IOBM) on tropical cyclone (TC) genesis in the north Indian Ocean (NIO) and western North Pacific (WNP) Ocean. Three types of warm (W1-W3) and cold IOBM (C1-C3) years are identified based on their persistence and connectivity with the Indian Ocean Dipole (IOD) mode. Type 1 is when the IOBM is decayed without conversion to the IOD, and type 2 is the conversion of the IOBM to the IOD with a phase change as a W event converts to a cold IOD or vice versa. Type 3 is a W event transforming into a positive IOD or a C event transforming into a negative IOD. During W1, in the WNP, TC genesis locations shift northward. They are less intense, whereas W3 TCs shift toward the southern WNP, far away from land, and significantly intensify from July to September (JAS). On the other hand, NIO TCs from October to December (OND) during W2 events are more concentrated in the Bay of Bengal (BoB). The W1–associated Genesis Potential Index (GPI) shows enhancement over the southern NIO from April to June (AMJ), extending into the WNP from JAS to OND. Most importantly, there is an increase in TCs south of 10°N in the WNP due to W3 and C2 events modulating vertical wind shear, mid-tropospheric relative humidity, relative vorticity at 850 hPa, and other related physical mechanisms. In contrast, a decrease in TCs south of 10°N in the WNP is caused by mechanisms associated with W2 and C3 events.Overall, changes in the large-scale environmental factors provide the background for the observed TC variation in both ocean basins during three types of IOBMs. This study, therefore, presents a detailed picture of the impact of IOBM events on TC activity over the NIO and WNP.Key Words: Indian Ocean Basin Mode, north Indian Ocean, western North Pacific, warm and cold IOBM, Genesis Potential Index
Assessment of The Applicability of Remotely Sensed Rainfall Products for Hydrological Analysis in The Levant Region (Case Study: Historical Palestine)
Authors: Jayousi Fakhry , O'Loughlin Fiachra
Published: March 2024

The availability of precipitation data from in-situ stations faces various challenges including varying quality and resolutions, improper distribution, and scarcity in many regions. This is particularly true for the West Bank. Hence, identifying the best available alternatives is a priority since high quality precipitation estimates are essential for most hydrological applications. This study focuses on examining the suitability of four satellite precipitation products (IMERG Final Run, PDIR-Now, CCS-CDR, CMORPH) in the Levant region taking Historical Palestine (West Bank, Israel) a case study. These precipitation products were compared to 502 in-situ rainfall stations (132 Palestinian and 370 Israeli) across the region at a daily time-step and had fine spatial resolutions varying 4-10 Km. Results show that IMERG estimates outperform all other products, with a mean R2 = 0.33 and Probability of Detection (POD) =0.7 with no adjustments applied. This R2 value is significantly higher than those found in other studies with similar climates. CMORPH was found to be the next best with a mean R2 =0.2 and POD = 0.4. The impact of elevations was also investigated and while IMERG was again the best overall, CCS-CDR performed better at lower elevations. Additionally, the satellite products were used to compare nearby Israeli and Palestinian stations and all satellites achieved higher results when compared to the Israeli stations. This potentially indicates the need for further investigation into the quality of Palestinian stations. Overall, this study found that IMERG provided the best performing satellite-based precipitation estimate for the Levant Region across a range of elevations, climatic regions, and rainfall thresholds. In addition to identifying the best performing date sets and examining newly released satellite products, this study’s finding will open the way to the application of these data sets for many hydrological purposes using available, easy-access remotely-sensed products.