bluuebunny/crossref_metadata_2025 huggingface dataset:
Heliophysics Applications on Education and Research using Cloud Computing
Authors: Raptis Savvas , Merkin Slava , Atunes Sandy , Smith Brent , Jeschke Chris , Winter Eric , Wiltberger Michael
Published: March 2024

Cloud computing has gained substantial momentum across diverse applications in recent years, notably in scientific computing, collaborative research, and large-scale machine learning operations. Its integration of data and code within a unified system facilitates swift data transfer and sharing among various research groups. However, despite its prominence in research, cloud computing usage in education is still limited beyond computer science courses.Embracing this technological shift presents an opportunity for graduate students and early-career researchers to familiarize themselves with these tools, contributing to open research and facilitating global collaboration.In this work, we explore from a user perspective the use of cloud computing in two NASA projects, particularly the Center for Geospace Storms (CGS) and Heliocloud, shedding light on how these initiatives can benefit the scientific community. By bridging higher education with academic and research environments through workshops and tutorials, these efforts can play a pivotal role in educating the next generation of researchers.
 Role of Carbon Dioxide, Ammonia, and Organic Acids in Buffering Atmospheric Acidity: The Distinct Contribution in Clouds and Aerosols 
Authors: Zheng Guangjie , Su Hang , Cheng Yafang
Published: March 2024

Acidity is one central parameter in atmospheric multiphase reactions, influencing aerosol formation and its effects on climate, health, and ecosystems. Weak acids and bases, mainly CO2, NH3, and organic acids, are long considered to play a role in regulating atmospheric acidity. However, unlike strong acids and bases, their importance and influencing mechanisms in a given aerosol or cloud droplet system remain to be clarified. Here, we investigate this issue with new insights provided by recent advances in the field, in particular, the multiphase buffer theory. We show that, in general, aerosol acidity is primarily buffered by NH3, with a negligible contribution from CO2 and a potential contribution from organic acids under certain conditions. For fogs, clouds, and rains, CO2, organic acids, and NH3may all provide certain buffering under higher pH levels (pH > ∼4). Despite the 104to 107 lower abundance of NH3and organic weak acids, their buffering effect can still be comparable to that of CO2. This is because the cloud pH is at the very far end of the CO2multiphase buffering range. This Perspective highlights the need for more comprehensive field observations under different conditions and further studies in the interactions among organic acids, acidity, and cloud chemistry.
BIOSOLID FROM SEWAGE TREATMENT PLANT INCREASES THE GROWTH OF JACK BEAN (Canavalia ensiformis) IN A COPPER CONTAMINATED SOIL
Authors: Silveira Andressa , Tamiozzo Fernanda , Santana Natielo , Jacques Rodrigo , Clasen Bárbara , Schein Edivan
Published: March 2024

Copper (Cu) mining have been carried out for more than a century in the Minas do Camaquã region, southern Brazil. Currently, this site has an extensive area impacted by the disposal of tailings and the soil has high levels of Cu. As a result of this contamination, the site has little or no vegetation cover, increasing the risk of other environmental compartments being affected. Phytoremediation can be used to mitigate this problem, and its efficiency can be enhanced by the use of organic amendments. Therefore, this study sought to evaluate the effect of sewage biosolids on the development of jack bean (Canavalia ensiformis) in a copper-contaminated soil after the cultivation of black oats (Avena strigosa). A biosolid obtained from the sludge of an aerobic domestic sewage treatment system was used in this study. The pots with soil from the area impacted by copper mining tailings (739 mg kg-1 of Cu Mehlih) received increasing doses of biosolid (0, 90, 180, 360, 720 and 1440 kg ha-1 of N) and black oat was grown in a greenhouse. After 75 days black oats were harvested, and then jack bean were cultivated in the same soil, using the same treatments of the black oat, but without new addition of biosolid. The jack bean was harvested at flowering to determine dry mass and copper content in tissues. The dry mass of the shoot increased with the addition of biosolid, but no significant difference was observed between treatments for dry mass of the roots. The highest dose (1440 kg ha-1 of N) promoted the highest dry mass production of the shoots (20 g pot-1), but did not differ (p < 0.001) from doses of 180, 360 and 720 kg ha-1 of N. In the control treatment (0 kg ha-1 of N) the plant presented less than 8 g pot-1of aerial biomass. The highest levels of Cu in shoot biomass were observed in the intermediate doses (180 and 360 kg ha-1 of N) and in the control treatment (average of 22.11 mg kg-1), differing (p < 0.05) only from the dose of 1440 kg ha-1 of N (12.42 mg kg-1). In the roots, no significant difference (p = 0.525) in Cu content was observed. Thus, our study indicates that intermediate doses (180 and 360 kg ha-1 of N) of biosolids promoted plant growth similar to the higher doses and increase the Cu contents in the shoot biomass. More studies must be carried out to evaluate the effects of biosolids on other soil and plant parameters, but our results indicate that the use of biosolids can be an alternative for increasing vegetation cover in phytoremediation strategies for soils contaminated by Cu mining tailings.
How can spatial parameter sensitivity analysis enhance streamflow calibration routines in hyper-resolution hydrological models?
Authors: Bacelar Luiz , Liu Hongli , Tang Guoquiang , Vergopolan Noemi , Mizukami Naoki , Wood Andy , Chaney Nathaniel
Published: March 2024

Efficiently modeling water and energy fluxes across spatial scales has historically involved grouping landscapes based on hydrological similarities. The HydroBlocks (HB) modeling framework, using unsupervised machine learning of high-resolution environmental datasets, emerges as a robust tool for representing heterogeneity in Land Surface Models (LSMs). This framework effectively discretizes complex gridded LSMs, such as Noah-MP, into spatially unstructured Hydrological Response Units (HRUs), facilitating the modeling of hydrological processes at hyper-resolution (10-100 m) with computational efficiency suitable for continental and global simulations. However, extending process-based hydrological models to such scales does not inherently ensure heightened simulation accuracy. For operational purposes, especially in flood warning systems, calibrating new LSMs remains imperative. Therefore, this study proposes a spatial parameter sensitivity methodology based on the pyVISCOUS algorithm, with the potential to facilitate HRU-level parameter calibration and enhance the application of hyper-resolution resolving LSMs for real-time streamflow prediction.Our investigation delves into the relationship between spatial parameter sensitivity and model discretization across the Contiguous United States (CONUS), mainly focusing on surface and subsurface runoff states. Two clustering architectures were used to generate HB HRUs for an ensemble of simulations varying Noah-MP LSM parameters. The simplified HB configuration clusters HRUs based on terrain and hillslope variations, while the formal HB incorporates finer-scale land heterogeneity from high-resolution land cover and soil properties maps. Results reveal that saturated hydraulic conductivity was considered the most sensitive parameter for runoff production independent of the HRU grid configuration. The infiltration controlling parameter REFDK was ranked as the second most important in first-order sensitivity and had a higher spatial impact (% of HRUs) over the experiment with a higher level of clustering small-scale heterogeneity. Lower sensitivities were found in HRUs classified as urban areas, while soil properties parameters demonstrate reduced sensitivity near streams, where the floodplain remains closer to saturation. We intend to demonstrate that excluding the least sensitive HRU groups within a defined parameter range from calibration could potentially minimize computational costs while preserving physically realistic spatial patterns of LSM fluxes and states at field-scale resolutions, mitigating artifacts introduced by conventional methods (e.g. constant parameter multiplier over subbasins).
Retrieval algorithm for GEMS aerosol optical properties: Improvement, validation, and post-processing
Authors: Cho Yeseul , Kim Jhoon , Go Sujung , Kim Mijin , Lee Seoyoung , Kim Minseok , Hong Hyunkee , Lee Dong-Won , Torres Omar
Published: March 2024

The Geostationary Environment Monitoring Spectrometer (GEMS), a pioneering Geostationary Earth Orbit (GEO) satellite instrument for air quality observation, is designed for atmospheric environmental monitoring and provides aerosol optical properties (AOPs). In this work, improvements to the GEMS aerosol retrieval algorithm, including spectral binning, surface reflectance estimation, cloud masking, and post-processing, are presented, along with validation results. These improvements aim to provide more accurate aerosol monitoring outcomes across Asia. Adopting spectral binning within the Look-Up Table (LUT) reduces random measurement errors and provides the stability of satellite data. Furthermore, Furthermore, a high-resolution surface reflectance database is constructed by considering monthly Background Aerosol Optical Depth (BAOD) values. This is based on the minimum reflectance method at the GEMS pixel resolution. The implementation of new cloud removal techniques enhances the accuary of cloud detection. Validation of GEMS AOD products against data from the AErosol RObotic NETwork (AERONET) and Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) from November 2021 to October 2022 reveals a robust correlation with AERONET AOD (R=0.792). Different validation outcomes are observed for different aerosol types, namely Highly Absorbing Fine, Dust, and Non-absorbing. GEMS Single Scattering Albedo (SSA) aligns well with AERONET data within acceptable error margins, although accuracy varies among aerosol types. When GEMS AOD exceeds 0.4, 42.76% of GEMS SSA values fall within the expected error range of ±0.03, and 67.25% fall within the range of ±0.05. The comparison of GEMS Aerosol Layer Height (ALH) with CALIOP data shows commendable agreement, with a mean discrepancy of -0.225 km and 55.29% (71.70%) of the data within ±1 km (±1.5 km). However, to address the issue of artifactual diurnal biases in AOD measurements, a machine learning-based post-processing correction method is developed. Post-process correction enhances GEMS AOD performance, reducing biases. In particular, the slope is close to 1, at 0.806 and the R is 0.897. Post-process correction also enhances GEMS SSA performance. 68.54% of GEMS SSA values fall within the expected error range of ±0.03, and 88.95% fall within the range of ±0.05.
Time-series InSAR monitoring and analysis of permafrost thaw-subsidence dynamics based on the ARIMA Method
Authors: Yu Wenyan , Jiang Mi , Cheng Xiao
Published: March 2024

The freezing and thawing processes of the active permafrost layer, driven by temperature variations between summer and winter, lead to surface seasonal uplift and subsidence, which can be captured by time-series InSAR techniques and associated permafrost modeling. As climate change introduces variations in factors like soil moisture and temperature, the seasonal surface deformation experiences interannual and fluctuating variations. However, these variations have often eluded capture due to either the spatiotemporal filtering processes to mitigate atmospheric delay of temporal InSAR and the approximate assumptions in permafrost deformation models. To better capture the dynamic changes in surface deformation caused by permafrost freeze-thaw processes, we develop a seasonally varying deformation method based on Autoregressive Integrated Moving Average Model (ARIMA) time series analysis. Through both synthetic data and real data experiments, we validate that the proposed method can provide more accurate deformation results while capturing the interannual variations in permafrost deformation. The real-data experiment, utilizing Sentinel-1 data, reveals that the maximum seasonal deformations in the continuous permafrost region of northern Alaska exhibit an increasing-decreasing trend from 2017 to 2021, with 2019 showing a relative maximum, correlating with the number of thawing days and air temperature in that year. This study contributes to a deeper understanding of freeze-thaw processes in permafrost regions, providing robust support for analyzing the impact of climate change on surface deformations in permafrost areas.
Innovating Solar Observation: The Potential of Volume Holographic Grating Filters as Optical Correlators
Authors: Antunes Vieira Luis Eduardo , de Oliveira Ivan , Tavares Felipe , Guarnieri Fernando , Miyazawa Keiji
Published: March 2024

This study investigates the feasibility of employing Volume Holographic Grating Filteras optical correlators in solar spectropolarimetry, a field that requires high-precision observations. VHGs, inscribed on photorefractivecrystals using a 633 nm wavelength laser, offer a unique method to simultaneously capture spatial and spectral data, a crucial advancement in observing solar phenomena. Despite challenges such as the fixed wavelength of the laser and the absence of thermal control during recording, the VHGs exhibit notable spectral and angular selectivity. The initial results demonstrate a spectral gradient in the VHG response, likely due to off-Bragg deviations. Future research directions include enhancing the laser capabilities to record VHGs with adjustable wavelengths, optimizing the optical setup, and conducting comprehensive field testing. These steps are aimed at refining the application of VHGs as optical correlators in solar observation, potentially expanding their capabilities in spectropolarimetry. By advancing VHG technology and adapting it for solar observation, the study contributes significantly to our understanding of solar magnetic activities and adds to the broader field of astrophysics. This research underscores the importance of continued innovation, collaboration, and the exploration of new applications in scientific technology.
Observations of solar wind-magnetosphere-ionosphere coupling and its impact on equatorial ionospheric electrodynamics during the March and April 2023 geomagnetic storms
Authors: Le Guan , Liu Guiping , Yizengaw Endawoke
Published: March 2024

The low-latitude ionosphere is effectively shielded from the high latitude convection electric field during geomagnetic quiet times because region-2 field-aligned currents associated with the partial ring current act to oppose the convection electric field associated with region-1 field-aligned currents. However, the low-latitude ionosphere can be directly coupled to the enhanced magnetospheric electric field through prompt penetration of convection electric field during periods of strong solar wind-magnetosphere interaction. The mechanisms that lead to the generation of prompt penetration electric field during enhanced solar wind-magnetosphere-ionosphere coupling are complex and not fully understood. We study the evolution of field-aligned currents and the equatorial electrojet during the March and April 2023 geomagnetic storm to understand the processes involving solar wind disturbances interacting with the magnetosphere and coupling into the polar ionosphere, and how the low-latitude ionosphere responded to the enhanced magnetosphere-ionosphere coupling. We will present the observations in the solar wind-magnetosphere-ionosphere system, in particular, field-aligned currents at high latitude ionosphere by Swarm and the equatorial electrojet by Swarm and ground-based magnetometers. 
Key controlling factors on the formation of Jura-type fold in eastern Sichuan Basin, South China: insights from analogue modelling with optical strain monitoring (Digital Image Correlation)
Authors: Feng Guimin , Adam Jürgen , Chen Shuping , Wang Xinpeng
Published: March 2024

Eastern Sichuan fold belt, a prolific hydrocarbon province in China, shows the similar fold styles to the Swiss Jura Mountain fold belt, which’s therefore called as Jura-type fold by Chinese geologists. However, it’s still a matter of geologist’s debate on the formation mechanism of the eastern Sichuan fold belt.To unravel how this type of fold trains form, a systematic scaled 2D contractional analogue experiments with composite materials were conducted. Silica-sand represents the overburden with added mica-flakes, and a stiff plasticine interlayer introducing different mechanical anisotropies. Viscous silicone rubber represents the salt detachment. The following 3 main issues have been investigated: 1) what type mechanical stratigraphy can form the fold train during lateral contraction; 2) what are the mutual interaction between faulting and folding during the formation process of detachment fold; 3）what are kinematics and its related strain distribution patterns for a detachment fold system.The modelling results indicate that the presence of a stiff plasticine layer is the key perquisite for the formation of a concentric fold train for the following reasons: 1) it encourages the shortening to be periodically accommodated by sinusoidal-symmetric buckle folds at the inceptive folding stage; 2) it can keep the break-thrust ramps from being activated with further shorting delaying the development of faulted detachment folds at the later folding stage. As for silicone detachment, it mainly plays a role in the amplification of detachment folds via the redistribution of ductile material between the syncline and anticline domain.DIC strain data show that the main sections of detachment fold-the limbs, especially in the forelimb, and the hinge are easily strained. More specifically, the normal faults and breakthrusts can form in the anticlinal hinge and limbs, respectively, when the detachment fold cannot be tightened any more. However, the strain is not easily accumulated in the syncline domain.Our modelling result together with the latest interpretation of seismic reflection suggest that the eastern Sichuan fold belt is a result of faulted detachment folds, mainly controlled by the competence contrast within the overburden and the thickness of both the weak viscous detachment and strong brittle overburden.Keywords: Eastern Sichuan Basin; Analogue modelling; DIC; Fold-thrust belt; Detachment fold
Exploring the entrainment of liquefied bed material in landslides
Authors: Waring Alexandra , Take Andy
Published: March 2024

Landslide runout analyses are conducted to predict the motion and distal reach of potential future landslides to inform landside hazard zonation, risk management, and the design of the optimal location and height of mitigation strategies such as barrier systems. A key uncertainty in these analyses relates to the erodibility and entrainment of sediment which may unexpectedly increase the volume of the landslide and affect travel distance. In this study we explore the case of a landslide overriding and entraining loose saturated valley floor sediments; in particular, whether such a scenario may cause the overridden sediments to liquefy, and if so, the extent to which that liquefaction affects the depth of erosion of the bed material and mobility of the slide.The presence of a loose saturated layer of soil at the base of a slope inherently introduces a soil region potentially prone to static liquefaction. This scenario fulfills the criteria required for instability: a) loose contractive soil, which happens to be co-located in an area that is both b) fully saturated, and c) within reach of a shear trigger (i.e., being overridden by the landslide). This scenario was reproduced in the Queen’s landslide flume, using a horizontal liquefiable bed of saturated fine sand 2 m in width, 7 m in length, and 0.3 m in height located at the bottom of the inclined portion of the flume. Landslides of up to 1,200 kg of granular material were then released from the top of a 6.5 m long slope inclined at 30 degrees to impact the bed at speeds of up to 6 m/s. Behaviour of the sand bed upon impact was captured using ultrahigh speed imaging of the landslide and bed profiles, a Blickfeld LiDAR sensor positioned opposite to the landslide to capture point cloud scans of the slide, and a linear array of porewater pressure sensors within the sand bed. Preliminary results of experiments attempting to liquefy the valley floor sediments are presented as we explore the requisite conditions for different rates of entrainment, and in extreme cases, liquefaction, of the sand bed, as well as the effect of liquefaction and entrainment on the speed and volume of the slide.  
Understanding the Marianas’ 2007 volcanic earthquake swarm: A perspective from fundamental quantities
Authors: orellana-rovirosa felipe , phipps morgan jason
Published: March 2024

In this project I am trying to understand the mechanics of the 2007 Marianas earthquake-swarm region and surrounding vicinity; located in the asthenosphere and lithosphere of the Marianas microplate above the subducting Pacific plate. The earthquake swarm exhibited seismicity for almost 2 years, with events occurring from depths of 300 km and up to the surface, right underneath the Marianas arc currently-active basaltic volcanoes.My approach is to estimate the magnitudes of mechanical variables (forces per unit area, forces per unit volume) that control the evolution of this system. These forces are evaluated for the swarm region, where the ambient rock is heavily fractured and intruded by migrating magmas, thus altered and weakened. From continuum-mechanics momentum equation, the specific terms under consideration are the elastic, viscous and inertial forces. These are evaluated as characteristic magnitudes, following approximated scaling forms of their analytical expressions. Additionally and alternatively, I am carrying out separate assessments of the viscous and elastic forces using visco-elastic (VE) theory (Kelvin-Voigt and Maxwell VE models).For comparison, I am also carrying out the corresponding estimates for Japan’s Mt. Yake (1998) volcanic earthquake swarm, and also, for a typical continental crustal seismogenic environment.  Importantly, the deformation of the system is very different when-and-where earthquakes are occurring, than at other times and locations. For this reason, my assessment distinguishes  two regimes: (i) short length-scales and short duration Co-Seismic, and (ii) long-length-scale and long duration A-/Inter-Seismic background. It is for these two time frames that I estimate the stress-strain and forces per unit volume. Additionally, associated energies and energy density-rates are also estimated, and finally the energy budget of the co-seismic and inter-seismic frameworks are studied.
Underestimating extremes due to random uncertainty
Authors: Sivadas Nithin , Sibeck David
Published: March 2024

As we attempt to infer a system's response to external driving from measurements, random errors in the measurement of the drivers can lead us to mistakenly infer a non-linear response. In particular, we are likely to underestimate the system's response during extreme and rare driving conditions due to uncertainty in the drivers. We demonstrate this phenomenon for extreme space weather and its impact on Earth's magnetosphere, where due to random errors in the measurements of solar wind drivers, there is a non-linear bias in the magnetosphere's response. We propose that the underlying statistical effect (related to the more well-known regression to the mean effect) is generalizable to the other fields that study different systems' responses to driving, like extreme climate studies. 
Growing season dynamics of net photosynthesis and leaf respiration for a mixed hardwood forest as inferred from flux-variance similarity
Authors: Scanlon Todd , Tatham Elizabeth
Published: March 2024

Ecosystem-scale estimates of net photosynthesis may be derived from eddy covariance measurements of net ecosystem exchange through the application of flux-variance similarity theory. Net photosynthesis, which is defined as carboxylation minus photorespiration and leaf respiration, differs from gross primary production by the leaf respiration term, which has been implicated as a potential source of error for traditional flux partitioning approaches. Here, we focus on seasonal dynamics of net photosynthesis and leaf respiration by deriving relevant variables (e.g. magnitude of dark respiration, light-saturated rate of net photosynthesis, sensitivity of leaf respiration to light intensity) through rectangular hyperbolic fits of net photosynthesis to photosynthetically active radiation (PAR) throughout the growing season. We find that the magnitude of dark leaf respiration decreases throughout the growing season, while the sensitivity of leaf respiration to light intensity and light-saturated net photosynthesis remain relatively stable. The level of PAR required for carboxylation minus photorespiration to exceed leaf respiration increases over the course of the growing season. We examine how environmental variables, specifically air temperature and volumetric soil moisture, influence these aspects of net photosynthesis. Estimates of leaf-level water use efficiency, a key parameter in the flux-variance similarity theory approach, are evaluated through comparisons with co-located measurements of solar induced fluorescence and sap flux.
Introducing the World Climate Research Program (WCRP) Academy
Authors: Hart Melissa , Lennard Chris , Jamero Ma. Laurice , Batino Lora , Borges de Amorim Pablo , Francis Feba , Kalele Dorcas
Published: March 2024

The WCRP Academy is the research training advisory and coordination arm of the World Climate Research Program. It is the flagship activity for WCRP´s mission: “to develop, share, and apply climate knowledge that contributes to societal well-being” and works to equip current and future climate scientists with the knowledge, skills and attributes required to tackle the world’s most pressing and challenging climate research questions. The Academy is a hub which connects training providers and users of training. Inclusion within the Academy implies that the training is of high quality and, as such, is a legitimate source of training and professional and capacity development platform that is targeted to climate scientists. In this presentation, we will introduce the Academy and our catalogue of climate science training, which collates in-house WCRP training activities and educational materials to the global science community. Further, the WCRP Academy encourages and invites all research and expert groups, academic and research institutions, government agencies and non-government organizations who provide climate science training and education to register as training providers and contribute to our online training catalogue.The WCRP Academy is building a global community of climate researchers at all career stages to provide global networking and development opportunities to facilitate lifelong learning, global equity, and skills matching for current and future research projects.  
Effect of wakes on chlorophyll-a at the Benham Bank
Authors: Alcantara Crizia , Sotto Lara , Sihay Janell Carmina , Ajoc Fiona Samantha , Bantay Kristine , Villanoy Cesar
Published: March 2024

Benham Bank is the shallowest part of Benham Rise, located offshore eastern Luzon at the Philippine Sea. It is a seamount with a flat top (guyot). This topographic feature causes the formation of wakes on the leeward side of the bank as the prevailing westward flowing currents pass through the area (NEC, Kurushio). Data from research cruises in 2018, 2019, and 2022 were compiled to investigate the formation of wakes at the Benham Bank and its consequences on chlorophyll-a distribution. ADCP data show a flow reversal at the western side of Benham Bank with currents flowing east and south at depths between 100-300 meters. The turbulence generated from the wake result in the erosion of the deep chlorophyll maximum (DCM) at the western side of the bank due to mixing. The increased mixing at the western side of the bank could have implications on the distribution of phytoplankton affecting their access to the photic zone as well as their availability for higher trophic levels.
Why and How to Increase Dataset Compression in RDIs and MIPs like CMIP7
Authors: Zender Charles
Published: March 2024

Research data infrastructures (RDIs) like the Coupled Model Intercomparison Project (CMIP) exemplify geoscientific dataset archive organization and applied informatics. The CMIP metadata and data policies have continuously co-evolved with mature and FAIR technologies (e.g., CF, OpenDAP, ESGF) that are, in turn, often adopted by other RDIs. Improved lossy and lossless compression support in the standard netCDF/HDF5 scientific software stack merit consideration for adoption in upcoming MIPs and RDIs like CMIP7. We have proposed a three point plan to CMIP7 to utilize modern lossy and lossless compression to reduce its storage and power requirements (and associated greenhouse gas emissions). The plan will boost the compression ratio of CMIP-like datasets by a factor of about three relative to CMIP6, preserve all scientifically meaningful data, and retain CF-compliance. We will present the plan, and discuss why and how to implement it in CMIP7 and other MIPs and RDIs.
Crust-mantle delamination enables continental subduction and flake tectonics: insights from numerical modelling
Authors: Rodrigues Nuno , Rosas Filipe , Riel Nicolas , Almeida Jaime , Gomes Afonso , Duarte João
Published: March 2024

Continental collision occurs when two continents are dragged towards each other by the pull of the attached subducting oceanic lithosphere. Previous geodynamic modeling studies of collisional systems focused on first-order processes (such as coupled/decoupled regimes, continental delamination, slab break-off dynamics) and regional or even local scale dynamics (e.g., exhumation of HP/UHP rocks, surface topography). However, continuous subduction of continental lithospheric mantle after the onset of collision and long-term dynamics of continental subduction remains poorly constrained. Long-term continental subduction bears major geodynamic implications for the evolution of past and present collision zones.To this aim, we use the geodynamic code LaMEM to perform high-resolution (2048 × 512) 2D buoyancy-driven numerical models, coupled with phase diagrams to account for density changes, of continued continental subduction with conditions that favor flake tectonics. We investigate the role of lower crust rheology to assess which rheological scenarios allow continental flaking and, thus, continued subduction of continental lithospheric mantle.Our preliminary results exhibit long-term continental subduction, due to decoupling of the lower crust from the subducting continental mantle and/or density changes. This separation allows the deformation to be transmitted onto the overriding plate, with the emplacement of the subducting plate crust onto the overriding plate spanning more than 350 km and lasting over 100 Myr.This work was funded by the Portuguese Fundação para a Ciência e a Tecnologia (FCT) I.P./MCTES through national funds (PIDDAC) – UIDB/50019/2020 (https://doi.org/10.54499/UIDB/50019/2020), UIDP/50019/2020 (https://doi.org/10.54499/UIDP/50019/2020) and LA/P/0068/2020 (https://doi.org/10.54499/LA/P/0068/2020), and through scholarship UI/BD/154679/2023.
Federated Climate Research Software: improving data and workflow management for climate researchers
Authors: Schwartz Misha , Chandan Deepak , Easterbrook Steve
Published: March 2024

Climate researchers have access to astronomical amounts of data; but finding that data and downloading it so that it can be useful for research can be burdensome and expensive.The team at Data Analytics for Canadian Climate Services (DACCS) is solving that problem by creating a new system for conducting climate research and providing the software to support it. The system works by providing researchers the tools to analyze the data where it’s hosted, eliminating the need to download the data at all.In order to accomplish this, the DACCS team has developed a software stack that includes the following services:- data hosting- data serving (using OPeNDAP protocols)- data search and cataloging- interactive computational environments preloaded with climate analysis tools- remote analysis tools (WPS and OGCAPI features)Partner organizations can deploy this software stack and choose to host any data that they wish. This data then becomes available to every other participating organization, allowing them seamless access each others data without having to move it for analysis.This system will allow researchers to more easily:- discover available data hosted all over the world- develop analysis workflows that can be run anywhere- share their work with collaborators without having to directly share dataThe DACCS team is currently participating in the Open Science Persistent Demonstrator (OSPD) initiative and we hope that this software will contribute to the ecosystem of earth science software platforms available today.
An overview of Japan’s Moonshot Goal 8 R&D program for controlling and modifying the weather by 205
Authors: Nakazawa Tetsuo , Miyoshi Takemasa , Sakajo Takashi , Takatama Kohei
Published: March 2024

Forecast and control are the two sides of a coin. Recent improvements in numerical weather prediction have led to the point where we can start discussing the control of complex, chaotic weather systems. The Japan’s Moonshot Goal 8 research and development (R&D) program or simply MS8 was launched in 2022 to control extreme weather events such as typhoons and torrential rains and to reduce damage from extreme winds and rains, so that we can realize a society safe from such disasters by 2050. As the important first step toward the next 3-decade R&D, MS8 prioritizes numerical simulation experiments to investigate the feasibility of weather control under the constraints of energy and technology within human’s capability in a foreseeable future. Thus far, MS8 achieved promising results to reduce a peak rainfall of heavy downpours, and more results are expected by ongoing efforts. MS8 also accelerates developing basic science and technologies for realizing weather control, such as advanced weather models, computational models of flood damage, and mathematical approaches to intervention optimization techniques for large dimensional systems. In addition, addressing ethical, legal, and social issues (ELSI) is essential and a priority in MS8. This presentation will provide an overview of MS8 with highlighting scientific results.

 
Development and Performance Evaluation of High-Resolution Climatology (ANAS23) in the Northeast Asian Seas 
Authors: Lee Jae-Ho , Kim Yong Sun , Kim Sung-Dae
Published: March 2024

This study describes a monthly Atlas for the Northeast Asian Seas 2023 (ANAS23) with a 1/10° horizontal resolution and 73 vertical levels. For ANAS23, over 1.6 million hydrographic profiles were analyzed, utilizing a simple kriging interpolation technique, which considers data density and their covariance at each grid point, along with a profile stabilizing method to minimize damage to water-mass structures. Comparison of ANAS23 with previously published atlases, repeated sectional observations, and satellite-based geostrophic current fields reveals that the ANAS23 provides reliable descriptions of the spatial distribution of water masses, currents, thermohaline fronts, and mesoscale eddies while avoiding spike-shape noises, vertical instabilities, and artificial waters, particularly over large-topographic features. ANAS23 could be utilized as a baseline to assess the dynamic state of climatological mean fields and their changes under evolving climate. The fact that uncertainty among atlases is still apparent, particularly in a region of scarce observations, calls for a collaborative international effort to collect qualified hydrographic observations for a better-performing regional atlas, thus improving predictive skills for future climate.
Testing a low-complexity model to decompose the multitemporal dynamics of soil erosion and sediment delivery in agricultural catchments
Authors: Matthews Francis , Panagos Panos , Fendrich Arthur , Verstraeten Gert
Published: March 2024

Testing and improving the capacity of soil erosion and sediment delivery models to simulate the response of soil erosion to the intra-annual dynamics of climatic drivers and disturbances (e.g., vegetation clearcutting, tillage events, wildfires) is critical to understand intolerable soil loss and catchment sediment yields. Here, we approach the trade-off between the need for model simplicity and temporally dynamic predictions by testing the ability of a low-complexity, spatially distributed model (WaTEM/SEDEM), to decompose the 15-day dynamics of soil erosion and sediment yield. A standardised RUSLE parameterisation and model implementation routine was applied to four arable-dominated catchments in North-West Europe with open-access validation data. We firstly show that when applied to simulate the multitemporal dynamics of sediment delivery, a standard assumption of a temporally static transport capacity within the model structure mostly cannot adequately replicate the multitemporal variability of sediment delivery. Instead, optimising a 5-parameter splines curve to determine the temporal profile of the transport capacity coefficient (ktc) based on the monthly average sediment yield improved the model performance and revealed clear seasonality in the sediment transport efficacy. Despite simulating similar temporally aggregated sediment yields, the introduction of seasonal dynamics into the transport capacity further caused a net reduction in the magnitudes of the spatially distributed sediment fluxes, compared to a temporally lumped approach. Published catchment observations infer this seasonality in sediment transport efficiency to attribute abundant vegetative boundaries in summer and increased soil crusting and runoff promotion in winter. Models operating at temporally aggregated timescales should account for the possibility of decoupling in time and space between gross erosion and sediment delivery related to these alternations between transport- and detachment-limited sediment transport capacity states. Despite the complexities and uncertainties involved in the temporal downscaling of WaTEM/SEDEM, we show the utility of this approach to: 1) link optimised multitemporal parameters to key missing model information components which may reduce error in gross erosion predictions (e.g. more consideration of antecedent soil conditions), 2) form a basis for strategically adding physical process-representation, with a focus on maintaining low model complexity while improving predictive skill, and 3) better understand the interdependencies between spatial fluxes and multitemporal dynamics when undertaking model predictions at large spatial and temporal scales.
Dissolved phosphorus concentrations are increasing in streams across the Great Lakes Basin
Authors: Basu Nandita , Singh Nitin , Van Meter Kim
Published: March 2024

Excess phosphorus from agricultural intensification has contributed to the eutrophication of rivers and lakes worldwide, including the transboundary Laurentian Great Lakes Basin. Algal blooms have surged in the past decade, threatening ecosystems, drinking water supplies and lake-dependent tourism economies in both large lakes (for example, Lake Erie) and smaller water bodies. Whereas previous research has focused mainly on phosphorus loads to Lake Erie, a comprehensive analysis of phosphorus species across the basin is lacking. Here we analyse changes in soluble reactive phosphorus and total phosphorus concentrations in over 370 watersheds across the Great Lakes Basin from 2003 to 2019. We find widespread increases in soluble phosphorus concentrations (83% of watersheds, with 46% showing significant increase), while total phosphorus concentrations are decreasing or non-significant. Utilizing random forest models, we identify small, forested watersheds at higher latitudes as the areas experiencing the largest relative increases in soluble phosphorus concentrations. Furthermore, we find winter temperatures to be a key driver of winter concentration trends. We propose that the increasing soluble phosphorus concentrations across the basin, along with warming temperatures, might be contributing to the increasing frequency and intensity of algal blooms, emphasizing the need for management strategies to prevent further water-quality degradation.
Climate, Ice, and Ocean Characteristics of the Thwaites Eastern Ice Shelf from two In-Situ Multi-Sensor Automated Stations
Authors: Scambos Ted , Truffer Martin , Collao-Barrios Gabi , Dotto Tiago , Kratt Chris , Tyler Scott , Pettit Erin
Published: March 2024

A pair of automated multi-sensor stations with satellite data downlinking were installed near the center of the Thwaites Eastern Ice Shelf (TEIS) in January, 2020 and continued operating (at least partially) until November, 2022. The stations, situated 4 km apart (initially near 75.05°S, 105.5°W) recorded and transmitted weather and snow accumulation data, position, images, firn and ice temperature, and ocean conditions through a suite of instruments managed with software and uplinked commands to conserve power and/or maximize observations of events. The stations, called Automated Meteorology-Ice-Geophysics Observing Systems, mark III (AMIGOS-III) are installed on a tower and adjacent ice borehole to measure air, ice, and ocean parameters. Weather and accumulation data from the stations spanning 22 months show a mean annual air temperature for TEIS of -14.6°C, with observed extremes of +1.7°C (08 Feb 2020) to -51.0°C (17 Aug 2021). Mean air pressure was 973.7 mbar (at ~25 m elevation). Winds are highly directional and dominated by dry katabatic flow from the southeast (from 115° to 130°); however, higher snowfall is correlated with winds from more easterly and northeasterly directions. Average annual snowfall in the observation period was 0.72 to 0.90 m water equivalent. Ice flow speed was observed to accelerate throughout the observation period, ranging from ~1.7 m/d in January 2020 to more than 2.2 m/d in late 2021. The rate of acceleration increased markedly after July 2020, coinciding with satellite observations of a more disrupted northern and western shear margin for TEIS. Maximum tidal amplitude is ~1.6 meters. Comparison with the CATS2008 tide model, after correction for IBE, showed a mean difference of ±17 cm. Ocean data was acquired from the two sub-shelf cavity moorings, each of which included paired SeaBird microCAT and Nortek Aquadopp sensors at mid-cavity depths (~520 m and ~317 m) and near-seabed depths (~746 m and ~785 m), in the modified Circumpolar Deep Water (mCDW) layer. These were augmented by a fiber optic thermal profiler system that measured both ice and ocean temperatures for 19 months. The fiber optic thermal data show a minimum temperature of -19.0°C in the interior, and lower temperature gradient suggesting truncation of the ice shelf base due to basal melting. Time-series of the profile data show very little basal melting of the ice at the two sites, but a thickening of the mCDW layer over the observation period. Overall, the AMIGOS-III data have supported six published studies to date, on ice shelf dynamics, ocean flow and layer properties, basal conditions, atmospheric river events, and weather. The units demonstrate the benefit of long-duration multi-sensor observing platforms in ice shelf or ice tongue areas.
Laboratory measurement of subcritical crack growth and healing in calcite using Double-Torsion tests
Authors: Nakagawa Seiji , Zhang Yida , Dadras Hooman , Hao Zhao , Voigtländer Anne , Gilbert Benjamin
Published: March 2024

Subcritical crack growth accelerates weathering of rocks and minerals, reduces the strength of rock slope, and affects the stability of subsurface faults. Under special circumstances, the produced cracks can also heal spontaneously (Self healing) regaining a part of the original tensile strength.  These crack behaviors are a manifestation of molecular-scale surface forces acting between the surfaces near the crack tip. As a part of the effort to understand how these forces control the subcritical crack growth and healing of geological materials, we examine the tensile crack behavior of calcite single crystals. A miniature Double-Torsion (DT) test system was developed for testing small plate samples (40 mm x 20 mm x 1.5 mm) cut out of optical-quality calcite single crystals (Iceland Spar crystals). These samples are oriented in such a way that the induced crack is along the (1014) plane (the primary cleavage plane). The main output of the experiment is the crack velocity (vc) vs the magnitude of applied driving force (stress intensity factor K or strain energy release rate G), which is a typical way to summarize the rate-dependent crack behavior. From the experiment, we have learned that (1) calcite exhibits strong healing behavior compared to materials such as glass or (amorphous) quartz in humid air and water, (2) healing is time dependent (the strength of a healed crack increases over time), (3) liquid water (rather than vapor) introduces strong hysteresis in the recracking vs healing behavior.   The obtained laboratory data are used to develop a mechanistic model for predicting macroscale crack behavior in rock, particularly in a water and electrolyte-rich environment.
Seasonal and interannual variations in landfast ice mass balance between 2009–2018 in Prydz Bay, East Antarctica
Authors: Li Na , Lei Ruibo , Heil Petra , Cheng Bin , Ding Minghu , Tian Zhongxiang , Li Bingrui
Published: March 2024

Landfast ice (LFI) is an indispensable component in the Antarctic coastal system, which is very important for coastal climate and ecological processes. However, the regional differences of LFI mass balance with respect to the seasonal and inter-annual variations and the impact factors responsible to those differences have not been investigated systematically in the Prydz Bay, i.e., the third largest bay along the Antarctic coast. We analyzed the data measured by 11 ice mass balance buoys (IMBs) obtained in the coastal areas off the Chinese Zhongshan station (ZS) and Australian Davis station (DS), and covered 2009–2010, 2013–2016 and 2018 ice seasons. We identified the local spatial changes in LFI based on the data.  The observed annual maximum ice thickness for LFI off ZS (DS) was 1.59±0.17 m (1.64±0.08 m), with the dominant influencing factors of air temperature anomaly, snow depth atop, local topography and wind regime, and oceanic heat flux. Larger interannual and local spatial variabilities for the seasonality of LFI mass balance were observed at ZS than at DS because of the differences in local topography and katabatic wind regime. LFI at DS (0.6±0.2 cm d-1) grew faster in winter due to the relatively low air temperature and small oceanic heat flux compared to that at ZS (0.5±0.2 cm d-1). Snow ice contributes up to 26% of the observed LFI maximum ice thickness at the offshore site close to ground icebergs off ZS because of substantial snow accumulation. Oceanic heat flux would promote the LFI growth during winter at the sites nearby Dålk Glacier off ZS because of the supercooled meltwater. At interannual timescale, we find that variability of LFI properties across the study domain prevailed, over any trend during the recent decades. Our results suggests that increased understanding of local atmospheric and oceanic conditions, as well as surface morphology and coastal bathymetry, are required to improve Antarctic LFI modelling at local and regional scale.