bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessing the Impacts of the 2020-22 Drought in California: Applying System Approaches to Improve Drought Early Warning Systems
Authors: Escriva-Bou Alvar , Medellin-Azuara Josue , Schwabe Kurt
Published: March 2024

The 2020–22 drought has been the driest three-year period on record in California. The drought led to fallowing of hundreds of thousands of hectares of cropland causing billions of dollars in lost revenues, dried up thousands of drinking water wells in small communities, harmed California’s freshwater ecosystems, and caused many cities to take unprecedented actions to ensure water reliability. Despite all these costly drought impacts, California lacks a statewide early warning system to identify and mitigate them. Some argue that California’s complex water system, with abundant storage and conveyance infrastructure, challenges the identification of drought drivers. But another important fact is that it does not exist a comprehensive source for multi-sectoral drought impacts.
The main goal of our study is to improve drought early warning systems in complex water systems by better understanding the linkages between drought indicators and drought impacts. To achieve that goal, we first obtain a spatially explicit timeline of the 2020-22 drought impacts by comparing different sources of information. We use the Drought Impact Reporter—which tracks drought impacts by scanning media for reports about drought impacts and collecting and mapping observations on drought-related conditions and impacts from agricultural producers and others—and discuss and complement this database with other reliable sources of information, such as agricultural production based on mixing evapotranspiration and agricultural economic models, drought impacts in cities from monthly agency reporting, dry wells for small communities from self-reported data, and environmental impacts from flow anomalies. Secondly, we assess how different drought indicators are able to predict the observed drought impacts in California’s complex water system. We use two different families of indicators: common hydro-meteorological indicators (such as SPI, SPEI, the US Drought Monitor, and others), and system-based drought indicators—which estimate drought hazard conditions by connecting water users and the drought conditions of their water sources, accounting for regulatory frameworks and management.
Our preliminary results show that reliable drought impact databases are essential to develop useful early warning systems, although there are challenges to identify and track location-specific drought impacts accurately. Also, we find that system approaches are essential to identify drought impacts in highly management systems, where users might not be dependent on local hydro-meteorological conditions.
Duplex Structures in the EastGRIP Ice Core - the Loss of Stratigraphic Integrity
Authors: Westhoff Julien , Bons Paul , Stoll Nicolas , Weikusat Ilka , Zeppenfeld Chantal , Erhardt Tobias , Dahl-Jensen Dorthe
Published: March 2024

The EastGRIP ice core is drilled through the Northeast Greenland Ice Stream, which has a surface velocity of 55 m/yr towards NNE at the drill site. Deriving a better understanding of internal deformation and the rheology within an ice stream is crucial for ice flow models and projections of future solid ice discharge. We use the line scanner to make the stratigraphy visible and document disturbances in the layering in the depth region from 1375 to 2120 m covering a large part of the Glacial Period. Disturbances are visible in cuts perpendicular to the ice flow direction, and not in cuts parallel to flow. Between these two extremes, we have a gradual change in type and amount of disturbances. As with all other ice cores, the ice in the EastGRIP ice core is thinned vertically. Due to the advanced thinning of layers, it is clear that the visible structures are not the remnants of surface features, such as sastrugi.  However, the disturbances, or deformation structures, are the result of strain caused by the stress field at the EastGRIP site, which is described by a compressional component perpendicular to and an extensional component parallel to the ice flow direction. In most samples cut perpendicular to ice flow, i.e. with the compressional setting visible, we find structures, very similar to geological duplex structures. We identify duplex structures extending the width of the core by the sudden change of layer tilt within one bag at a time. Duplex structures are confined by layer parallel shear zones, with tilted layers in between them. The small-scale shear zones only become evident due to the deformation they cause and can extend well beyond these visible structures. We furthermore suggest, that shear zones are present parallel to layering, but do not show up, as a lateral displacement of layers, does not disrupt the vertical profiles. We discuss one example, from a depth of 1651 m (26 ky b2k), in detail. We further investigate approx. 30 m of chemical CFA data, mainly NH4+ and Ca++, from the same depth. We find peaks that double, in both the visual stratigraphy as well as the CFA data. These may be a result of the duplex structures that stack the stratigraphy and have the potential to disturb the climate record. Our results display the importance of understanding internal deformation when interpreting the climate record.
Microcomputed Tomography Unravels CO2-fluid/rock Interaction in Elba's Carbonated Serpentinites
Authors: Rizzo Roberto Emanuele , Papeschi Samuele , Baroncini Edoardo , Vannucchi Paola
Published: March 2024

Carbonation of serpentinites is a crucial factor in controlling the earthquake cycle in subduction zones. Serpentinites are commonly found within subduction zones, both in the mantle wedge above subducting slabs and on the incoming plate, formed from peridotites exposed directly on the ocean floor. Carbonation of these serpentinites often results from the “contamination” of CO2-rich fluids derived from sediments involved in the subduction. This process leads to the formation of carbonate minerals within the serpentinite, which in turn influences the mechanical properties of the rock. A critical factor affecting the spatial and temporal progress of carbonation reactions - and thus their potential to trigger mechanical instabilities at the plate boundary - is the emergence of a permeable network of cracks and pores, which facilitates the interaction of CO2-rich fluids with the serpentinite rocks.We present a detailed three-dimensional (3D) characterization of variously carbonated serpentinite samples through computed microtomographic (µCT) imaging integrated with a machine learning algorithm (i.e. Random Forest classifier) to segment the different mineral phases. Machine learning offers a robust and accurate means of identifying and quantifying the carbonate phases, leveraging the Random Forest capacity for handling complex, multidimensional data. This allows for a comprehensive 3D examination of the alteration phases affecting the serpentinite samples and provides quantitative insights into the volumes and geometries of the carbonate vein networks. Our focus is on samples from an exhumed subduction channel separating  the fossil Cretaceous – Eocene accretionary prism (Ligurian Units) from the continent-derived nappes of the Northern Apennines. The subduction channel, part of the Norsi – Cavo Complex, is exposed over approximately 10 km along the N-S strike on the Island of Elba, consisting of oceanic sediments and ultramafic rocks detached from the prism base. Our analyses reveal that carbonation preferentially follows pre-existing serpentine veins, exploiting inherent anisotropies in the rock. In addition, the geometry of the vein network, as illuminated by the µCT 3D data, can help us to correlate with the carbonation timescale and fluid fluxes, as inferred from geochemical data.The presence of carbonate-rich fluids can be responsible for increasing pore-fluid pressure, pushing the rock toward failure. The formation of extensive carbonate vein networks can also lead to a net volume increase in the original serpentinite, thus increasing instability. The observed preferential distribution of carbonates along pre-existing structures not only provides crucial insights into the mechanics of subduction zones but also offers valuable implications for CO2storage models, highlighting potential fluid migration and reaction pathways.
Genesis and Decay of Baroclinic Eddies in the Seasonally Ice-Covered Arctic Ocean
Authors: Meneghello Gianluca , Marshall John , Lique Camille , Isachsen Pål Erik , Doddridge Edward , Campin Jean-Michel , Regan Heather , Talandier Claude
Published: March 2024

We explore the origin and evolution of mesoscale eddies in the seasonally ice-covered interior Arctic Ocean. Observations of ocean currents show a curious, and hitherto unexplained, vertical and temporal distribution of mesoscale activity. A marked seasonal cycle is found close to the surface: strong eddy activity during summer, observed from both satellites and moorings, is followed by very quiet winters. In contrast, subsurface eddies persist all year long within the deeper halocline and below.We find that the surface seasonal cycle is controlled by friction with sea ice, dissipating existing eddies and preventing the growth of new ones. In contrast, subsurface eddies, enabled by interior potential vorticity gradients and shielded by a strong stratification at a depth of approximately 50 m, can grow independently of the presence of sea ice. We address possible implications for the transport of water masses between the margins and the interior of the Arctic basin, and for climate models’ ability to capture the fundamental difference in mesoscale activity between ice-covered and ice-free regions.
An 8 ka record of drought and fire dynamics in the southern European Alps based on biomarker analyses 
Authors: Danius Lisa , Strobel Paul , Prochnow Maximilian , Zech Roland , Bliedtner Marcel
Published: March 2024

The southern European Alps are currently suffering from serious drought conditions and wildfires due to climate change. For this reason, paleoenvironmental research is fundamental in this vulnerable region to better understand the interactions between climate, humans, and landscape in the past, which are still largely unknown. Therefore, we established an 8 ka sediment record from Lago di Pusiano in the Brianza region (northern Italy) to reconstruct previous drought and wildfire dynamics since the Neolithic period using biomarker analyses. Specifically, besides well-established geochemical analyses, we use compound-specific hydrogen isotope analyses (δ2H) of n-alkanes to reconstruct hydroclimatic conditions and polycyclic aromatic hydrocarbons (PAHs) to reconstruct fire activities.Our results show that δ2Hof the terrestrial n‑C29 and n-C31, which both reflect the δ2H signal of the growing season precipitation, is enriched during the Mid Holocene (~8 to 4.2 cal. ka BP), depleted from ~4.2 to 2.5 cal. ka BP and enriched from ~2.5 to 0.4 cal. ka BP. On longer timescales, we interpret our terrestrial δ2H to reflect the isolation-driven temperature change due to northern hemispheric cooling, showing an ongoing depletion in δ2H from the Mid to Late Holocene. However, on shorter timescales, especially during the Late Holocene, terrestrial δ2H can be overprinted by changes in the moisture source of precipitation, which are mostly related to the North Atlantic Oscillation (NAO) and the position of the Westerlies. Compared to the terrestrial n-alkanes, δ2H of the aquatic n‑C25, which reflects the δ2H signal of lake water, is generally more enriched due to lake water evaporation. Consequently, the offset between aquatic and terrestrial δ2H gives a valuable indication about evaporation at Lago di Pusiano and indicates wetter conditions during phases of enriched terrestrial δ2H and dryer conditions during depleted terrestrial δ2H.PAHs are abundant throughout the sediment core and increase during periods of higher regional human activity (e.g., Bronze Age pile dwellings ~4 cal. ka, Roman settlements ~2 cal. ka, and during Medieval times ~1 cal. ka), especially strongly during industrialization. The occurrence of PAHs in the Pusiano sediments, especially the large amount of high molecular PAHs, indicates significant local fire episodes with biomass combustion at high burning temperatures. The comparison of PAHs and δ2H of n‑alkanes suggests the presence of increased fire activities during wetter periods, possibly due to higher biomass availability as fuel for more extensive wildfires, and/or increased anthropogenic burning due to increased human presence during wetter periods.
AutoVal: A framework for scientific validation of flood catastrophe models
Authors: Massam Ashleigh , Burns Douglas , Jordan Owen , Nix Barbara , O'Malley Niamh , Oldham Philip , Sahu Brijkishore , Vasiljeva Ksenija
Published: March 2024

Catastrophe models are complex numerical models that simulate extreme events to estimate the economic cost of natural disasters, usually developed by model providers and adopted by clients in the (re)insurance, finance, and other sectors. Before adopting a model, the model user typically engages in an evaluation process that can be a challenging and resource-intensive task, and challenging for non-experts. This process is not standardised across the industry, so model users need to establish their approach from scratch. Yet effective evaluation is repetitive and takes time and resources – an effort that is being duplicated across organisations and teams, which would be better placed on an exploratory side of testing that progresses knowledge and understanding of models. By automating the repetitive part of model evaluation, data visualisations and results can be reproduced quickly. This would allow for more frequent assessment, leading to an improved understanding of the limitations of catastrophe models and increased confidence in the insights gained from using a catastrophe model.We present AutoVal, a catastrophe model evaluation tool that automates standard loss validation tests. The premise of AutoVal is very simple: third party data is transformed at the point of use into benchmark expectations, for assessment against catastrophe model outputs. In our work to date, third party insurance claims data or published estimates of event losses are used to calculate average annual losses, loss exceedance curves, and map spatial and temporal distributions of loss for comparison with modelled estimates. Further work is ongoing to expand the capability of AutoVal to evaluate components within the natural catastrophe model, including vulnerability functions and hazard maps.AutoVal can aid model users from both industry and academic backgrounds through the application of standard, repeatable tests. It assists with the effective review of model configurations across a range of perils or scenarios, allowing decision makers to better understand model sensitivity and behaviour. AutoVal also has the potential to remove the repetition in model evaluation, allowing for more frequent model evaluation and faster feedback loops between developers and users. In this presentation, we will share our progress so far with designing and automating the evaluation of our catastrophe models, including – but not limited to – standardised schemas for benchmark data, validation exercises to assess modelled estimates of loss, and new approaches to interpreting model sensitivity.To realise the potential of AutoVal, we invite colleagues from the risk management sector to discuss our ongoing work towards establishing a set of benchmark tests that can complement industry-wide progress towards consistent and common standards.
Integrated RIsks MAnagement for more resilient societies at the global changes era (IRIMA)
Authors: Grandjean Gilles , Georges Didier , Boudia Soraya
Published: March 2024

Between 1980 and 2022, weather- and climate-related extremes caused economic losses of assets estimated at EUR 650 billion in the EU. To face this challenge, increasing with ongoing warming, it seems necessary to stimulate and coordinate the European effort on multidisciplinarity. The proposed approach, as developed in the France 2023 Risks-IRIMA program, is hightly holistic and integrative of knowledge. It aims to largely federate geosciences, climate sciences, engineering, data and digital sciences, as well as human and social sciences. These different disciplines are now heavily involved in these issues, but still work too much in silos and / or, sometimes, without direct interaction with society. We propose here un way to capitalize on available knowledge and develop inter and transdisciplinary methodological approaches, so as to better detect, quantify and anticipate risks, understanding their complexity (extreme events, multiple risks), and unsteady, coupling and cascading effects, multi-scale dynamics, taking better account of human and socio-economic vulnerabilities, etc.) It will also be a question of making better use of scientific data and citizen knowledge, and of better valuing new technologies, particularly those of information, by consolidating data acquisition and assimilation / cascading effect modeling / decision support / policy implementation for crisis management, citizen protection and anticipation of future risks related to climate change and anthropization. Through this renewed effort, research on risks should strongly contribute to the sustainable transformation of society: societal well-being, better preparedness, adaptation and resilience in the face of risks, and strengthen social, technical and economic capabilities in a world shaped by global change.
Assessing the spatial and temporal trophic properties of the Marano and Grado Lagoon, Italy with the coupled physical-biogeochemical model SHYFEM-BFM 
Authors: Scroccaro Isabella , Laurent Celia , Aveytua Leslie , Solidoro Cosimo , Canu Donata
Published: March 2024

Coastal and transitional areas worldwide are affected by a range of human pressures and are subjected to high natural variability. In the Marano and Grado lagoon, located in the densely anthropized north-eastern coastal area of Italy, the conservation of biodiversity and the presence of important socio-economic activities require planning and management tools and measures. Coupled physical and biogeochemical models are useful tools to support trophic studies in complex systems such as the Marano and Grado lagoon by integrating field information with relevant hydrodynamic and biogeochemical processes shaping the system. The coupled SHYFEM–BFM model was applied to the Marano-Grado lagoon, adding new features to account for the contribution of macrophytes (such as seagrasses). Results were validated against available in situ observations, and trophic properties were investigated using trophic state indices that allow to reproduce spatial and temporal variability under different scenarios.
RADEM on JUICE's first observations of the interplanetary radiation environment 
Authors: Hajdas Wojtek , Galli Andre ,   RADEM collaboration
Published: March 2024

RADEM (Radiation Hard Electron Monitor) is a versatile detector of energetic particles designed for measurements of Jupiter's harsh radiation environment. It is one of the instruments on the ESA JUICE (Jupiter Icy Moons Explorer) mission launched on April 14th, 2023. RADEM was switched on for a short commissioning phase shortly after the spacecraft launch and since August 2023 has been carrying on observations of the interplanetary radiation environment. The instrument will be operational throughout the JUICE mission from its cruise phase to the nominal scientific segment around the giant planet and its moons. RADEM was designed to detect electrons up to 40 MeV and protons up to 250 MeV enabling for covering of the most intense and hazardous regimes of the Jupiter radiation belts. Energy distributions of both protons and electrons are unfolded using eight semi-logarithmic energy bins. It allows for measurements of the spectral shapes and dynamic changes in the radiation intensity. RADEM also contains a detector sensitive to the direction of the incoming radiation with an angular coverage of 35% of the sky. Combined spectroscopic and angular measurements will allow for more accurate studies and mapping of the radiation around Jupiter and its moons. The instrument also has a dedicated heavy-ion detector designed to measure heavy-ion linear energy transfer between 0.1 and 10 MeV/cm/mg-1. RADEM's primary purpose as a radiation monitor is to observe mission dose levels for safety concerns of the spacecraft and its scientific payload. In addition, its spectroscopic measurements in the higher energy range provide valuable extensions to other instruments from the JUICE payload. In particular, the Particle Environmental Package suite of instruments optimized for particle and ion energies up to about 1 MeV will obtain data prolongation up to about 100 MeV. RADEM operation during the cruise phase opens up a unique opportunity for conducting real-time, continuous observations of the Solar System radiation environment. It covers the current, twenty-fifth solar cycle including the solar maximum expected in 2025. With the JUICE-RADEM monitoring the radiation in the space between Venus and Mars orbits one obtains a data set useful for our future manned and unmanned explorations of these two neighboring planets. In this contribution, we will present the first RADEM observations of the interplanetary radiation environment including initial reports of detected SEPs (Solar Energetic Particles). The presented data set will cover the period since September 2023. The data will be correlated with observations from other instruments flying onboard spacecraft around the Earth or in interplanetary space such as e.g. BeppiColombo and Solar Orbiter. 
Monitoring subsurface changes in a quick clay area during extreme weather
Authors: Bruland Charlotte , Köhler Andreas , Dichiarante Anna Maria , Oye Volker , Van Bever Ivan
Published: March 2024

Some of the more densely populated areas in Norway are in potential quick clay zones. When disturbed, the structure of quick clay can suddenly collapse, and behave and flow as a liquid, potentially having disastrous impact over large areas.  One of the triggering factors for quick clay slides is heavy rainfall. Here, we focus on passive seismic data from two Raspberry shake sensors located in an urban area in Oslo, Norway with quick clay in the subsurface. Using coda wave interferometry, near-surface velocity variations are estimated during the extreme weather ”Hans” (August 2023).We compute auto-correlations and single station cross-correlations of anthropogenic seismic noise (> 1 Hz) over a two-year period leading up to ”Hans”. We observe environmental velocity fluctuations well correlated with air temperature, precipitation and the water level in a nearby river. In particular, freezing and thawing produces strong changes in seismic velocity (up to 4 %). Disregarding freezing, we see the largest change in seismic velocity following the heavy rainfall associated with ”Hans”. This extreme event is associated with a sharp velocity drop anti-correlated with pore pressure. The surface wave-coda is sensitive to changes in shear wave velocity, which in turn can be used to detect changes of the subsurface properties. Therefore, observed velocity variations at the site could have potential for monitoring and early warning of quick clay instabilities.
Step-by-Step Strategies to Tackle Coastal Erosion: Insights from Calabaia Beach (Calabria, Italy)
Authors: Brunetti Guglielmo Federico Antonio , Carini Manuela , Scarcella Maria Antonietta , Xavier Pilier Francisco , Maiolo Mario
Published: March 2024

Coastal areas globally are invaluable assets and strategic resources from both environmental and social perspectives, as well as for the sustainable development of the marine economy, often referred to as “Blue Growth”. This understanding highlights the crucial need to protect coastal areas from climate change phenomena such as sea-level rise, flooding, and erosion. Previous research has shown the high vulnerability of the Mediterranean Sea's coasts to these phenomena, with ecosystems and biodiversity increasingly under threat. Despite past efforts to address these issues, many aspects still require further investigation, and solutions necessitate a holistic approach and a step-by-step strategy. Our research contributes to this context by providing valuable insights from Calabaia Beach (Calabria, Italy), where specific step-by-step strategies were implemented to mitigate erosion processes and restore the coastal and marine environment. The research site, located within the Marine Experimental Station of Capo Tirone (Belvedere Marittimo, Calabria, Italy), is of significant relevance as it has experienced various sea-defense interventions over the years, ranging from hard defenses to soft defenses, to the adoption of nature-based solutions. This study highlights that investigating the efficacy of these interventions over time can offer essential insights into the potential of each to sustainably curb erosion processes. From this standpoint, practitioners can establish a solid foundation to predict how future interventions for tackling erosion could effectively impact the entire coastal ecosystem of the area. Moreover, our research suggests that a step-by-step approach could be implemented also for aspects related to local hydrodynamics, pollutant dispersion, seawater intrusion, and marine biology. The case study of Calabaia Beach clearly illustrates that a time-dependent strategy could be successfully applied when there is a need to balance coastal environmental protection with social interests and the development of “Blue Growth”. This approach could be further explored in other case studies, keeping in mind that the specific characteristics of the area represent a determining factor.Acknowledgements. This research was supported by ”NAUTILOS” project (GA 101000825) and by the Next Generation EU - Italian NRRP, Mission 4, Component 2, Investment 1.5, call for the creation and strengthening of ’Innovation Ecosystems’, building ’Territorial R&D Leaders’ (D. D. 2021/3277) - project Tech4You, n. ECS0000009. This work reflects only the authors’ views and opinions, neither the Ministry for University and Research nor the European Commission can be considered responsible for them.
Sustainable Utilization of Groundwater Resources through Well of Construction Sites under Climate Change: A Case Study in Taichung City, Taiwan
Authors: Liu Chiung-Ling , Chan Hsun-Chuan , Wu I-Yu , Chien Chao-Chun , Wu Ming-Che , Chang Shu–Fang
Published: March 2024

Global climate change has led to an increase risk of drought. It reflects the importance of effective water resource management. In 2011, Taiwan experienced a severe water crisis during a drought, with Taichung bearing the brunt of its impacts. However, this brought to light the use of groundwater resources against drought. Groundwater from dewatering on construction sites played a critical role in supporting industrial and domestic uses while providing approximately 5,000 tons of water daily during the drought. Collaborative efforts resulted in the swift integration of groundwater from nine construction sites into the tap water supply system, providing about 100,000 tons daily, sufficient to support around 400,000 people.Generally, construction site groundwater is underutilized. This study aims to gather fundamental information on wells at construction sites of Taichung and analyze current water yields from various perspectives. The objective is to identify cases for long-term promotion, propose corresponding measures, and develop a sustainable management model. The results will provide specific strategies and timelines for ongoing, sustainable groundwater utilization efforts at construction sites.Keywords: drought; construction-site well; groundwater resource; sustainable utilization
Integrating machine learning technique with SWAT model to optimize the prediction of peak flow in the Beas River basin, India
Authors: Raaj Saran , Gupta Vivek , Singh Vishal , Shukla Dericks
Published: March 2024

Accurately predicting and simulating runoff is more significant in Beas River Basin, due to the uncertainty that posed by the climate change. This uncertainty brought challenges and difficulties to efficiently manage the water resources. Beas river basin is prone to flash flood area, hence estimating the peak flow is critical in this basin. Due to the presence of dams and reservoirs in the basin, they pose difficulties in predicting peak flow and daily streamflow. In this study, for modelling streamflow physics-based machine learning (ML) model in combination with semi-distributed process-based SWAT hydrological model have been evaluated. In this study performance of Elastic Net (EN) ML technique have been compared with calibrated-SWAT (cSWAT) model. The root mean square error (RMSE), coefficient of determination (R2) and Nash–Sutcliffe efficiency (NSE) were used to evaluate the performance of all the models. The findings of the study revealed that the in comparison to cSWAT model, ML model performed better. However, when ML regression models are paired with uncalibrated SWAT (uSWAT-ML) few models outperformed cSWAT model. The R2, RMSE and NSE value of cSWAT model is 0.73, 276.92 m3/s, and 0.72 which shows good performance. EN obtained better performance with R2, RMSE and NSE value of 0.89, 0.87 and 158.31 m3 respectively. Hence the approached uSWAT-ML have been used to predict the peak flow values, with models EN got better results with R2 value of 0.71. The results indicates that the integrating ML model with uncalibrated SWAT model yields reliable results for predicting daily streamflow and peak flow values.
Relationship between appearance of polar stratospheric clouds and ozone destruction over Northern polar region in 2011 and 2020 based on CALIPSO observations
Authors: Nakajima Hideaki , Ogawa Miu , Kita Kazuyuki , Pitts Michael C.
Published: March 2024

Although stratospheric ozone loss occurs every year in Antarctica, Arctic ozone loss occurs only when stratospheric temperature gets low. Recently, substantial ozone loss occurred in Arctic in 1997, 2011, and 2020. Especially, the magnitude of Arctic ozone losses in 2011 and 2020 was comparable to that of in Antarctica. Satellite CALIPSO was launched in 2006, and is still in operation and measuring global cloud properties using two-wavelength lidars. It measures distribution and characteristics of polar stratospheric clouds (PSC) over both polar regions. In this study, we analyzed characteristics of Arctic PSCs in 2011 and 2020, and their effects on polar ozone loss. Figure 1 (not shown in this abstract) shows distribution and types of Arctic PSCs along a CALIPSO satellite track on 4 January 2011 over downstream of Greenland. The appearance of wave-ice-type PSC due to mountain-induce lee wave can be seen.In this analysis, distribution and types of Arctic PSC was analyzed for the altitudes of 20, 17.5, and 15 km for each CALIPSO orbit (15 orbits per day in maximum) from January to March in 2011 and 2020. Local temperature and HNO3 amount by Aura/MLS were also analyzed to see the PSC formation condition and the magnitude of denitrification. As a result, there were no major differences between the appearance of PSCs in January and February. However, stratospheric temperature was low in 2020 compared with 2011 in March, and appearance of PSC was greater in 2020. Ozone depletion started to occur in March when sunlight was available over the Arctic, and record-high ozone depletion was observed in 2020. The reason of this low temperature in 2020 could be attributed to the unusually strong polar vortex over the Arctic in this year.
Instrument-to-Instrument translation: An AI tool to intercalibrate, enhance and super-resolve solar observations
Authors: Schirninger Christoph , Veronig Astrid , Jarolim Robert , Johnson J. Emmanuel , Jungbluth Anna , Galvez Richard , Freischem Lilli , Spalding Anne
Published: March 2024

Various instruments are used to study the Sun, including ground-based observatories and space telescopes. These data products are constantly changing due to technological improvements, different instrumentation, or atmospheric effects. However, for certain applications such as ground-based solar image reconstruction or solar cycle studies, enhanced and combined data products are necessary.We present a general AI tool called Instrument-to-Instrument (ITI; Jarolim et al. 2023) translation, which is capable of translating datasets between two different image domains. This approach enables instrument intercalibration, image enhancement, mitigation of quality degradations, and super-resolution across multiple wavelength bands. The tool is built on unpaired image-to-image translation, which enables a wide range of applications, where no spatial or temporal overlap is required between the considered datasets.In this presentation, we highlight ITI as a general tool for Heliospheric applications and demonstrate its capabilities by applying it to data from Solar Orbiter/EUI, PROBA2/SWAP, and the Solar Dynamics Observatory/AIA in order to achieve a homogenous, machine-learning ready dataset that combines three different EUV imagers. The direct comparison of aligned observations shows the close relation of ITI-enhanced and real high-quality observations. The evaluation of light-curves demonstrates an improved inter-calibration.ITI is provided open-source to the community  and can be easily applied to novel datasets and various research applications. This research is funded through a NASA 22-MDRAIT22-0018 award (No 80NSSC23K1045) and managed by Trillium Technologies, Inc (trillium.tech)
Assessing the Impact of Stabilization Measures on a Slow-Moving Landslide in Arcos de La Frontera town (SW Spain) using InSAR
Authors: Bru Guadalupe , Ezquerro Pablo , Azañón Jose M. , Mateos Rosa M. , Tsige Meaza , Béjar-Pizarro Marta , Guardiola-Albert Carolina
Published: March 2024

The town of Arcos de la Frontera is a historical heritage ensemble located in Andalusia (SW Spain), perched on a nearly vertical 100 m calcarenites cliff and surrounded by gentle slopes characterized by being composed of weathered clayey soil from the Guadalquivir Blue Marls formation. This formation, extensively present in the region, poses significant geotechnical challenges, particularly when weathered, exhibiting low strength parameters. Between the end of the 20th and the beginning of the 21st century, the town underwent significant urban expansion. New building blocks were constructed in the head of a complex slow-moving earth slide, whose activity had been producing documented damages to linear infrastructures and urban assets since the 1970s. The most affected structures in this area by slope movements belong to La Verbena neighbourhood, which started to deteriorate soon after their construction in 2007. By October 2009, severe structural damage prompted the evacuation of 22 families, and one of the buildings was officially declared derelict in March 2010 following intense precipitation. Although local authorities commissioned geotechnical investigations and stabilization measures, these initiatives did not approach the complex landslide as a holistic problem. Instead, the works were applied locally with the objective of stabilizing La Verbena neighbourhood. These measures included jet grouting of cement-based injections and drainage and were implemented intermittently in La Verbena from 2011 to 2021, incurring a cost of €4.1 million.In this investigation, we employed a long-term motion InSAR analysis landslide activity using Sentinel-1 data acquired in both ascending and descending orbit from January 2016 to March 2023. The primary focus was to evaluate the efficacy of local stabilization efforts and compare our InSAR results to in-situ monitoring surveys. Our results indicate a clear deceleration of the landslide head post-mid-2018, providing evidence of the effectiveness of the local stabilization measures. Before this period, the Line-of-Sight (LOS) mean velocity of the entire landslide head in ascending and descending orbits was 2.2 cm/year and 1.3 cm/year, respectively, decreasing to 0.43 cm/year and 0.23 cm/year.The findings of our study demostrate that the local stabilization works in La Verbena have influenced a significantly larger area, extending beyond the directly intervened zone and effectively stabilizing the entire head of the landslide. By providing data beyond the boundaries of the in-situ monitoring area, InSAR has enriched our insights into the effects of stabilization works, emphasizing the benefits of integrating InSAR techniques as a complementary tool to traditional geotechnical monitoring methods.
Towards a comprehensive rock glacier inventory in the Swiss Alps
Authors: Duvanel Thibaut , Lambiel Christophe , Delaloye Reynald
Published: March 2024

Rock glaciers are debris landforms typical of high mountain environments. They can be identified in the landscape by their steep frontal and lateral margins, as well as their lobed surface and the frequent occurrence of ridges and furrows (RGIK, 2023). Their morphology is related to the downslope creeping movement. Over the recent years, the scientific community has highlighted the importance of studying these landforms to improve our understanding of the impacts of climate change on high mountain regions. 

The RoDynAlps research project, funded by the Swiss National Foundation and led by the Universities of Fribourg, Lausanne, Zurich and the WSL Institute for Snow and Avalanche Research, aims to better understand the dynamics of rock glaciers in the Swiss Alps. One of the main objectives of the project is to assess the current state of the rock glaciers in the Swiss Alps, in the continuity of an initiative launched by Delaloye et al. (2019), with the result being a comprehensive inventory of rock glaciers in the Swiss Alps, including kinematic characterization. To this aim, we are applying a standard methodology developed by a consortium of experts (RGIK, 2023).  

This poster presents preliminary results obtained in the Valais Alps.  More than 1300 rock glaciers were identified, based on aerial ortho-images and on the new 0.5 m SwissSURFACE3D Lidar DEM analyses. In a next step, kinematic data will be computed from a wide range of interferograms derived from Sentinel 1 images 2020–2022. Then, statistical and spatial analysis will be performed in order to improve our knowledge on the factor governing the spatial distribution and the kinematics of the rock glaciers in the investigated region.  

REFERENCES  

Delaloye R., Barboux C., Gärtner-Roer I., Lambiel C., Pellet, C., Phillips, M. and Scapozza, C. (2019). Toward the first national rock glacier inventory in the Swiss Alps (SwissRG2020). Abstract, 17th Swiss Geoscience Meeting, Fribourg 2019 

RGIK 2023. Guidelines for inventorying rock glaciers: baseline and practical concepts (version 1.0). IPA Action Group Rock glacier inventories and kinematics, 26 pp. 
Diurnal Vegetation Moisture Dynamics and Water Stress: Insights from GNSS Reflectometry-Derived Vegetation Water Content
Authors: Asgarimehr Milad , Wickert Jens , Camps Adriano , Entekhabi Dara
Published: March 2024

The dynamics of Vegetation Water Content (VWC) throughout the day reflect how plants cope with water stress, trying to replenish lost water during daylight hours. Traditional radar sensors have shown sensitivity to diurnal vegetation moisture fluctuations but struggle due to their limited sampling rates, making it difficult to monitor daily patterns effectively. Innovations like Global Navigation Satellite Systems Reflectometry (GNSS-R) present a promising solution to overcome these limitations.In this study, we leverage GNSS-R measurements from the NASA Cyclone (CYGNSS) mission, launched in late 2016, to study diurnal VWC cycles in Amazon's evergreen forests. CYGNSS offers high sampling rates and increased sensitivity to VWC, penetrating vegetation layers effectively with longer L-band wavelengths. The eight satellites of CYGNSS provide frequent measurements in tropical regions across different times of the day.Our results uncover distinct differences between morning and evening VWCs over Amazon. We have observed a strong correlation (R = 0.75) between VWC and Vapor Pressure Deficit (VPD) throughout 2019, indicating VPD as a crucial factor influencing water stress. The diurnal VWC cycles in the Amazonian peatland demonstrate disruptions during arid periods and emphasize the significant role of VPD in governing vegetation diurnal moisture dynamics.Our findings bridge the information gap on water stress in vegetation, showing the potential of VWC derived from advanced remote sensing technologies. It complements in-situ data on water potential gradients, offering valuable insights into vegetation water status in these critical ecosystems.
Evaluating the implementation of the new urban parameterization for the ICON atmospheric model: results over Italy
Authors: Campanale Angelo , Adinolfi Marianna , Raffa Mario , Schulz Jan-Peter , Mercogliano Paola
Published: March 2024

The increasing in the resolution of atmospheric models for numerical weather prediction and climate simulations allows a more accurate description of the physical processes at urban scale. Furthermore, as the world continues to warm, urban areas are expected to face the brunt of the impacts due to large populations and higher temperatures.In all this scenario, the interest in proper modelling the physical processes in urban areas has gained wide attention from the research community. In particular, the convection-permitting atmospheric models, associated with urban parameterizations, are able to resolve the heterogeneity of cities with applications for heat stress assessment and the development of urban climate adaptation and mitigation strategies. Generally, these schemes parametrize the effects of buildings, streets and other man-made impervious surfaces on energy, water and momentum exchanges between surface and atmosphere, accounting also for the anthropogenic heat flux, as a heat source from the surface to the atmosphere due to human activities.In this perspective, a bulk urban canopy parameterization, TERRA_URB, has been developed for the multi-layer land surface scheme of the COSMO regional atmospheric model. This parameterization has already demonstrated to be able to properly take into account the overall properties of urban areas and to correctly reproduce the prominent urban meteorological characteristics for different European cities. Thus, in the framework of the transition from the COSMO model to the new Icosahedral Nonhydrostatic (ICON) Weather and Climate regional model, TERRA_URB needs to be implemented in ICON.In this work, we present the results for TERRA_URB in the ICON-LAM (limited area model), for some cities of the Italian peninsula at 2km resolution. The main outcome of this study is that the porting of the TERRA URB scheme in ICON is satisfactorily completed, and it reasonably reproduces urban effects, like Urban Heat Islands, while improving air temperature forecasts for the investigated urban areas. The results constitute an updating of numerical weather prediction and climate simulations for urban modelling applications, although further investigations aimed at enhancing the calibration of the model parameterization and introduction of more realistic urban canopy parameters are needed.
Patterns of compound drought and heatwave events in the Mediterranean and their atmospheric circulation drivers
Authors: Philippopoulos Kostas , Zazani Athina-Kyriaki , Cartalis Constantinos , Agathangelidis Ilias
Published: March 2024

Recent research reveals that extreme climate events arise from the complex interplay of multiple physical drivers across different spatial and temporal scales. Although traditional climate risk and impact assessments consider individual extreme events, it is the synergy of such events that can trigger cascading impacts, exceeding the adaptive capacity of the underlying systems, and resulting in major climate and societal impacts. Compound climate events are defined as the combination of multiple drivers and/or hazards that contribute to societal or environmental risk. This work will address the field of extreme climate and weather events through the assessment of the co-occurrence of droughts and heatwave (CDHW) events. Large-scale circulation drivers, such as atmospheric blocking influence the occurrence and the perseverance of CDHW events. The scope of this study is to evaluate the current state of climate over the Mediterranean in terms of droughts and heatwaves, focusing on their compound impacts, and identifying their large-scale atmospheric circulation drivers. The identification of the CDHW climatology is carried out through the improvement of a novel index tailored to the Mediterranean region. According to the peak-over-threshold approach, CDHW events occur when two or more contributing climate indicators simultaneously exceed a relative threshold. Multiple indicator combinations are examined, and an optimum compound index is developed that successfully quantifies the interrelations of droughts and heatwaves. Extensive statistical analysis is carried out to evaluate their frequency, duration, intensity, and trends during the historical climate period. The analysis is based on reanalysis products and following a data-driven methodology, the role of large-scale atmospheric circulation drivers on the onset, duration, and intensity of the CDHW events is examined using the synoptic climatology approach. The analysis provides the hot-spot regions of CDHW high-impact phenomena over the Mediterranean region and their association with the large-scale atmospheric circulation.
Validating ENSO Feedbacks in Climate Models Using a Causal Discovery Method
Authors: Schultz Emma , Coumou Dim , Massmann Michael
Published: March 2024

The El Niño-Southern Oscillation (ENSO) stands out as the dominant driver of climate fluctuations on interannual timescales. As ENSO causes extreme weather events in the Pacific region and beyond, it has wide ranging socio-economic impacts. Over the past decades, a strengthening in the temperature gradient is observed between the Western and Eastern Pacific. However, climate model simulations do not depict this strengthening trend. Here we explore if the Bjerknes feedback is well represented in climate models, and if not whether this could explain the discrepancy between the observed and modeled trends. The Bjerkness feedback represents the dominant feedback processes between atmosphere and ocean that drive ENSO variability. A causal discovery method, the PCMCI algorithm, is used to construct causal networks of key variables in the Bjerknes feedback: near surface temperatures, sea level pressure and trade winds across the Pacific Ocean. Causal networks are constructed for time periods 1950-1982 and 1982-2014, based on both reanalysis data and climate model simulations. The observed changes between causal networks based on the early and later period are examined. The analysis reveals a strengthening causal influence of trade winds on sea level pressure and temperatures in networks based on reanalysis data. This significant strengthening trend is absent in networks based on climate model simulations. As an increased influence of the trade winds would have a cooling effect on Central and Eastern Pacific, this might explain why there is no observed warming in the Central and Eastern Pacific over the past decades, and thus a strengthened temperature gradient. The lack of this strengthening causal influence of trade winds in climate models might thus explain why the models do show a warming over the Eastern Pacific, weakening the temperature gradient.