bluuebunny/crossref_metadata_2025 huggingface dataset:
Temporally compounding energy droughts in European electricity systems with hydropower
Authors: van der Most Lieke , van der Wiel Karin , Gerbens-Leenes Winnie , Benders René , Bintanja Richard
Published: March 2024

As renewable energy capacities continue to grow (rapidly), the European electricity system will become vulnerable to extreme events in the form of energy droughts—periods of low production coinciding with high demand. In this work, we use a large model ensemble of 1600 years of daily climate data in conjunction with an energy production and demand modelling framework and consider present-day installed capacities to compute the full distribution of renewable electricity production and demand in the present-day climate. This approach enables us to examine in detail the specific events at the tail of the distribution that pose the highest risks to energy security.In particular, this study focuses on energy droughts occurring once every ten years in six European countries: Sweden, Norway, Italy, Spain, France, and Switzerland, chosen because of their specific renewable energy mix including hydropower. We analyze energy drought events and their corresponding meteorological conditions and find that energy droughts result from processes that cause (temporally) compounding impacts in the energy and meteorological system. These processes can turn what might have been short-term droughts into prolonged, cumulative energy crises. For instance, low reservoir inflows in spring quadruple the chance of prolonged energy droughts: reduced snowpack and rainfall lower hydro-availability but also dry-out subsoils, increasing the chance of heatwaves and thereby extending the energy problems into summer.We identify and evaluate three compounding energy/climate conditions and quantify the associated risks. These results can inform the energy modelling community where high-risk meteorological conditions can be applied in power system models to optimize and analyze the robustness of future energy system designs, and provide insights on the specific characteristics of the risks of multiyear energy droughts to policymakers and energy companies.
India Water Model: A Transboundary Water Modeling System Over South Asia and a 75-year Daily Streamflow Reanalysis
Authors: Prakash Ved , Saharia Manabendra
Published: March 2024

Streamflow has a crucial role in the global water cycle. The demand for long-term daily streamflow observations becomes essential for robust water resources planning, hydroclimatic extremes analysis, and informed ecological assessments. However, there is a lack of availability of this type of dataset, particularly concerning the river basins of South Asia daily. The hydrologic-hydrodynamic model can simulate the streamflow over the domain. However, these models are not well calibrated to provide the locally relevant streamflow simulation daily. In response to this crucial knowledge deficit, in this study, we developed a state-of-the-art hydrological-hydrodynamic model to simulate daily streamflow spanning the years 1949 to 2022 across river basins South Asia by calibrating the model with observed daily streamflow. Leveraging meteorological observations meticulously gathered by the India Meteorological Department (IMD) inside India, and Modern-Era Retrospective Analysis for Research and Applications, Version 2 (MERRA2) outside domain, our model integrates the Noah MP as the land surface model and the HyMAP routing model to generate intricate daily streamflow dynamics within the South Asian sub-continental river basins. We calibrated the model at the 173-gauge stations against observed streamflow over South Asia. The calibration and validation time periods were 3 and 5 years respectively. This process ensures the adaptability and relevance to the local nuances of Basins in the model, aligning the simulated daily streamflow patterns with observed data. A comprehensive examination of the model's performance provides good results, with key metrics such as Kling-Gupta Model Efficiency (KGE), coefficient of determination (R2), and Nash-Sutcliffe efficiency (NSE) consistently exceeding a median threshold of 0.34. Taking our analysis further, we calculated the KGE skill score of the dataset, we found that 83/173 in calibration and 72/173 in validation showed KGE skill score more than 0.08. This extensive reconstruction and evaluation of streamflow dynamics not only contribute significantly to filling the knowledge gap but also lay the foundation for more precise and informed water management strategies in the dynamic landscape of South Asia's river basins.
A Hybrid Deep Learning Framework to Generate Locally Relevant Streamflow from Large Scale Hydrological Models 
Authors: Magotra Bhanu , Saharia Manabendra
Published: March 2024

 The large scale physically based hydrological model outputs can exhibit uncertainties due to various sources such as model structure, parameterization, and inputs. Moreover, these outputs are often available at a coarser resolution due to high computational and data requirements, thus limiting their applicability in operational hydrology. In this study, we present a deep learning framework that reduces the uncertainty in the streamflow generated by a continental scale physical model, using a two-stage process. The hydrological model is setup over the Indian Subcontinent with outputs at 0.1° and daily resolution from 1981-2021. The outputs, including streamflow, are generated by a six-member ensemble consisting of two land surface models (LSM) namely: Noah MP 3.6 and CLSM Fortuna v2.5, and three meteorological forcings namely: MERRA2, CHIRPS and IMD. First, we predict the residual in each of the six-member ensemble streamflow by training a Long Short-Term Memory Network (LSTM) on 220 catchments using dynamic meteorological inputs and static catchment attributes. Next, we pass the six corrected streamflow outputs to another LSTM layer that learns to optimally combine them along with integrating a three-day moving average of observed streamflow, generating an accurate prediction of 1-day ahead streamflow for each catchment.  Our results showcase the efficacy of this hybrid framework in significantly enhancing the skill of large-scale hydrological models, imprpoving the national median Kling-Gupta Efficiency (KGE) from 0.01 to 0.628. Moreover, we reproduced extreme event conditions at specific locations with higher accuracy. This study leverages the power of deep learning and extensive observed data to derive locally relevant streamflow predictions from a large-scale hydrological model, offering practical solutions for refining hydrological models and informing water resource management strategies.  
Using STEREO-A data from April to November 2023 as a sub-L1 monitor
Authors: Weiler Eva , Möstl Christian , Davies Emma E. , Amerstorfer Tanja , Amerstorfer Ute V. , Rüdisser Hannah T. , Bailey Rachel L. , Veronig Astrid , Horbury Timothy , Lugaz Noé , Le Louëdec Justin , Bauer Maike
Published: March 2024

Sub-L1 monitors are currently being researched in mission concepts for small satellites and may be deployed on distant retrograde orbits around the Earth in the future. Depending on the location of the sub-L1 monitor, the lead time for the arrival of coronal mass ejections (CMEs) and for determining their geo-effectiveness could be prolonged. If the sub-L1 monitor was to orbit the Earth at a distance of 0.05 AU, as is proposed for the MIIST mission, for example, Dst predictions could be made up to 5 hours in advance. The close encounter of STEREO-A and Wind from April 2023 to November 2023 represents such a constellation, and therefore allows us to investigate potential impacts of future sub-L1 missions. Following the method of Bailey et al. (2020), the data from STEREO-A are mapped to L1, taking into account an expansion of the CME. We then calculate the Dst of the temporally and spatially shifted data, and compare the result with the Dst calculated from L1 solar wind data and the observed Dst. In this way, we can analyse and quantify the implications of sub-L1 monitors on space weather forecasting.The events included in our study are part of the HELIO4CAST lineup catalog v2.0 (https://helioforecast.space/lineups). The catalogue includes CMEs that were observed by at least two spacecraft such as Solar Orbiter, Parker Solar Probe, BepiColombo, STEREO-A, and Wind. In contrast to single in situ measurements, which do not adequately capture the vast structure of CMEs, the events in the catalogue allow us to study the temporal and spatial evolution of CMEs and improve our current understanding of the large-scale structure of their magnetic flux ropes. In view of the upcoming maximum of solar cycle 25, further multipoint events are expected to be continuously added to the catalogue.
The Copernicus Sentinel-4 UVN mission: status and ongoing activities at EUMETSAT  
Authors: Kumar Vinod , Rüthrich Frank , Garcia Sebastian Gimeno , Gu Myojeong , Pandey Praveen , Taberner Malcolm , Lindstrot Rasmus , Dobber Marcel , Grandell Jochen , Ahlers Berit , Veihelmann Ben , Courreges-Lacoste Gregory Bazalgette , Bojkov Bojan
Published: March 2024

The Copernicus Sentinel-4/UVN mission is Europe's contribution to the virtual constellation of air quality related sensors in geostationary orbit. It is planned to be launched in 2025 on board EUMETSAT’s Meteosat Third Generation – Sounder (MTG-S) platform and complement the Korean GEMS and American TEMPO instruments which are already in orbit over Asia and North America, respectively.Following the space segment development and in-orbit commissioning under ESA responsibility, EUMETSAT will be responsible for operations, data processing and continuous calibration/validation of the Copernicus Sentinel-4 instruments and the derived operational products. The state-of-the-art UVN sounder onboard the MTG-S satellite covers the UV to NIR spectral range to provide hourly high spatial resolution measurements of several trace gas and aerosol concentrations and vertical profiles, crucial for monitoring atmospheric pollution. Other instruments (e.g., the Infrared Sounder, Lightning Imager and Flexible Combined Imager) onboard the MTG platforms will provide complementary information about temperature, clouds, and atmospheric constituents like water vapour.In this presentation, we will cover the progress achieved at EUMETSAT for the Sentinel-4 UVN mission with respect to the readiness of the ground segment including the in-orbit calibration key data (CKD) generation. We will put forward the in-flight measurement sequences and manoeuvres that are meant to secure the quality of the generated L1 and L2 data. We will show the results of the system validation test performed with the EUMETSAT ground segment and Telespazio after the successful mechanical integration of the instrument onto the platform in September 2023. We will also present the ongoing preparation and planned activities concerning the development of tools and facilities for monitoring and operational validation.
Characterizing drained lake basins across the Arctic 
Authors: Bergstedt Helena , Bartsch Annett , von Baeckmann Clemens , Jones Benjamin , Breen Amy , Wolter Juliane , Farquharson Louise , Grosse Guido , Kanevskiy Mikhail
Published: March 2024

Lakes and drained lake basins (DLB) are common landforms in permafrost lowland regions in the Arctic and widely cover 50% to 75% of the landscape in parts of Alaska, Siberia, and Canada. Lakes and DLBs create a heterogeneous and dynamic mosaic of terrain units, providing unique habitats for flora and fauna. Lakes and drained lake basins in permafrost regions play a crucial role in the regions landscape and ecosystem processes, influencing permafrost dynamics, biogeochemical processes, the hydrologic regime, as well as carbon cycling and greenhouse gas emissions. Depending on time passed since drainage of a given DLB, characteristics like surface roughness, vegetation, moisture, and abundance of ponds may vary between basins. Spatial heterogeneity within a single basin also varies between basins of different age. The mosaic of vegetative and geomorphic succession within DLBs and the distinct differences between DLBs and surrounding areas can be discriminated with remote sensing and used to derive a landscape-scale classification. In situ observations of these surface characteristics of DLBs are crucial for a better understanding of these features but can only describe a small percentage of existing DLBs.In this study, we use a novel pan-Arctic assessment on DLB occurrence and the ESA Permafrost_cci circumpolar landcover unit data set based on Sentinel-1 and Sentinel-2 satellite imagery to assess the inter and intra-DLB spatial heterogeneity of surface characteristics. Building on existing research, we sort DLBs into distinct groups corresponding to previously published DLB age classification schemes (young, medium, old and ancient DLBs). DLB groupings show different landcover distribution within the basins, allowing for assumptions about the relative time passed since a drainage event occurred. To compliment and verify our remote sensing-based approach, a wide array of field data was collected at multiple sites across the Arctic, including on the Alaska North Slope. First results show distinct differences between DLBs within the study area, based on the landcover occurring within basins and other surface properties. Comprehensive mapping and characterizing of DLBs on a circumpolar scale will allow for improved parametrization of regional to pan-Arctic modeling efforts and improve our understanding of DLBs as a crucial landform in Arctic permafrost landscapes.  
Impact analysis of processing strategies for long-term GPS zenith tropospheric delay (ZTD)
Authors: Bai Jingna , Lou Yidong , Zhang Weixing , Zhou Yaozong , Zhang Zhenyi , Shi Chuang , Liu Jingnan
Published: March 2024

Homogenized atmospheric water vapour data is an important prerequisite for climate analysis. Compared with other techniques, GPS has inherent homogeneity advantage, but it still requires reprocessing and homogenization to eliminate impacts of applied strategy and observation environmental changes where a selection of proper processing strategies is critical. Here, we reprocess GPS observations at 44 IGS stations during 1995 to 2014. We focus on the influence of the mapping function, the elevation cut-off angle and homogenization on long-term reprocessing results, in particular for Zenith Tropospheric Delays (ZTD) products. Moreover, for the first time, we include the mapping function (VMF3) and exploit homogenized radiosonde data as a reference for ZTD trend evaluations. Our analysis shows that both site position and ZTD solutions achieved the best accuracy when using VMF3 and 3° elevation cut-off angle. Regarding the long-term ZTD trends, we find that homogenization can reduce the trend inconsistency among different elevation cut-off angles. ZTD trend results show that the impact of mapping functions is very small. On the other hand, the discrepancy can reach 0.60 mm/year by using different elevation cut-off angles. We suggest the low elevation cut-off angles (3° or 7°) for the best estimates of ZTD reprocessing time series when compared to homogenized radiosonde data or ERA5 reference time series.
Constellation of N Spacecraft : the Aliasing Problem
Authors: Chanteur Gérard M.
Published: March 2024

Constellations of N spacecraft allow to separate spatial and temporal variations of the electromagnetic field in space as demonstrated by achievements of CLUSTER and MMS missions. Future missions in preparation, involving more than four spacecraft, will offer new opportunities beside proper technological progress in sensors and electronic design : the genuine and promising aspect is the number of spacecraft larger than four. Four spacecraft is the minimal configuration to estimate gradients and to do spatial filtering in three dimensions. More than four spacecraft gives additional degrees of freedom by weighting the constellation ; a numerical weight is attributed to each spacecraft for computing gradients or doing spatial filtering. It has been early recognized that spatial filtering by a constellation of spacecraft is limited by spatial aliasing ; theoretical considerations, for example dispersion relations, allow to discriminate aliased energy peaks. Discriminating aliased energy peaks with more than four space spacecraft is possible just by changing the weighting of the constellation as will be shown for the simplest case N=5. First the aliasing equation is reminded, then the fundamental cell is defined and visualized, and it is shown that aliased peaks are moving when changing the weighting. Meanwhile non-aliased peaks are unaffected.
A web-based and data-driven approach to paleogeographic reconstructions
Authors: Aminov Jovid , Dupont-Nivet Guillaume , Tirandozova Nozigul , Poblete Fernando , Rakhimjanov Ibragim , Amonbekov Loiq , Rikamov Ruslan
Published: March 2024

Paleogeographic maps illustrate the distribution of land and sea, as well as the topography of the Earth’s surface during different geological periods based on the compilation of a wide range of geological and geophysical datasets. These maps provide boundary conditions for various models of the Earth’s systems, including climate, mantle convection, and land surface evolution. A number of software programs and computer algorithms have been developed in the past three decades to reconstruct either the past positions of continents and oceans or their elevation and depth. We recently developed the open-source and user friendly "Terra Antiqua", allowing users to create digital paleogeographic maps in a Geographic Information System (GIS) environment (QGIS), using various tools that are easy to operate in combination with Gplates, a widely used software for plate tectonic reconstructions. The next step is to develop a comprehensive and integrated solution easily accessible on the web that can automate most of the steps involved in reconstructing past plate configurations and topography. We present here a web application ("Terra Antiqua online") that we are developing for the creation of digital paleogeographic maps. The web application has two parts: (1) The front-end uses CesiumJS, an open-source JavaScript library for making 3D globes and maps, to visualize the databases and let the users interact with it.  (2) The back-end uses Python algorithms and libraries such as GDAL and pyGPlates to process the data and perform tectonic and hypsometric reconstructions.  Terra Antiqua online uses pyGplates API to access existing tectonic models and apply them to rotate plate positions and datasets to their past position. New developments are allowing it to estimate the elevation, depth and distribution of the land and sea by automatically processing various geological proxy data (e.g. paleofacies maps, paleo-elevation proxies, fossils databases etc…) according to physically based algorithms. The project further aims to incorporate web-based landscape modeling tools and develop a community around a geological database and paleogeographic reconstruction methods and standards.
Real-time fluvial flood mapping for impact-based flood early warning in Denmark 
Authors: Plum Charlotte , Butts Michael , Trolle Dennis , Nielsen Anders
Published: March 2024

Estimating flood (inundation) extent for river systems is a key element for impact-based flood forecasting and warning. Hydrodynamic Inundation mapping is widely used for planning for local flood mitigation measures and climate adaptation strategies. An interesting but challenging option is to use these models in real-time to provide locally relevant and impact-based flood warning. The challenge is that these methods can be computationally demanding and therefore may not be able to provide timely forecasts and effective warnings for early action. One approach used in practical applications, is to simulate pre-defined flood scenarios that are calculated, ahead of time, and then used as a look-up table by flood forecasters. However, this approach may not necessarily capture the actual flood dynamics and requires time-consuming manual interpretation. The Danish Meteorological Institute (DMI) has recently been appointed as the national authority for flood forecasting for Denmark, and is tasked with developing and implementing a flood forecasting and early warning. The initial focus is on informing decision-making for local and national emergency services. In this study, we explore approximate, but computationally efficient, flood mapping for flood early warning. As a starting point, we have formulated a static flood mapping approach, based on an extension of the deterministic 8-node approach, and established an approximate hydrodynamic model, using LISFLOOD-FP for the Vejle River in Denmark. Adopting these simpler approaches recognizes that for flood warning the most relevant information is the identification of the areas at risk during an extreme flood event rather than the precise extent and magnitude of flooding. The township of Vejle, located near the mouth of Vejle River in a deep lowland glacial valley, is subject to frequent flooding from the coast as well as fluvial flooding from heavy rainfall and cloudbursts. Severe flooding from extreme rainfall occurred in the Vejle River during both February and March 2019. To evaluate the impact of the approximations used, we have compared the resulting flood map with drone observations of flood extent, photographs and satellite data during the flood in March 2019. These evaluations will guide DMI in developing operational flood mapping for flood early warning and emergency actions across the whole of Denmark.
Multi-GPU Material Point Method Solver for Landslide Simulation
Authors: Huo Zenan , Jaboyedoff Michel , Podladchikov Yury , Räss Ludovic , Wyser Emmanuel
Published: March 2024

We present a high-performance Material Point Method (MPM) numerical solver for simulating the landslide run-out process with high resolution. The solver has been adapted to run on multi-GPU platforms. The current version is backend-agnostic, operating efficiently across various CPU and GPU hardware from different vendors, utilizing the same codebase. We evaluate multiple performance metrics and ensure minimal data synchronization between different devices at each iteration. We validate the solver's accuracy by comparing the simulation results of an aluminum-bar collapse with the corresponding experimental outcomes. Consistency is observed between numerical and experimental results for the free and failure surfaces. The results also indicate favorable performance scalability in high-resolution models, significantly enhancing computational efficiency. Further, we simulate the slumping mechanic problem with a simplified landslide geometry. The results show that the shear band develops within the high plastic strain area. The failure surface is in good agreement with the solution reported by Huang[1] et al., demonstrating that MPM can accurately handle failure and large deformation problems as they occur in landslides. Our multi-GPU implementation using MPI makes it possible to perform large-scale simulations that enable to tackle research in the field of geotechnical engineering.References:[1]. Huang, Peng, Shun-li Li, Hu Guo, and Zhi-ming Hao. “Large Deformation Failure Analysis of the Soil Slope Based on the Material Point Method.” Computational Geosciences 19, no. 4 (August 2015): 951–63. https://doi.org/10.1007/s10596-015-9512-9.
Rock Magnetic Studies of The Early Jurassic Middle Eocene Volcanic and Sedimentary Rocks of the Eastern Pontides
Authors: Algur Bahadırhan Sefa , Kayın Sercan , Dokuz Abdurrahman , Hisarlı Z. Mümtaz , İşseven Turgay
Published: March 2024

In this research, we revealed the findings from rock magnetic analyses, including Isothermal Remanent Magnetization (IRM) and High-Temperature Susceptibility (HTS), conducted on various volcanic and sedimentary rocks from the Early Jurassic – Middle Eocene located in the Eastern Pontides. These magnetic studies offer valuable insights into the minerals causing magnetization, as well as the composition and changes in magnetic minerals within these rocks. The experiments were carried out at the Doç.Dr. Yılmaz İspir Paleomagnetism Laboratory, Istanbul University-Cerrahpaşa.For the Isothermal Remanent Magnetization (IRM) studies, samples were collected from 57 sites in the Eastern Pontides, ensuring representation of each rock type. The analysis revealed that “Hematite”, “Magnetite”, and a combination of “Hematite + Magnetite” are the minerals responsible for magnetization in the selected samples. Moreover, it was discovered that in 41 out of the 57 sites, the samples reached saturation magnetization, indicating that "Magnetite" is the predominant mineral responsible for magnetization. The magnetic susceptibility of the rocks was examined during the heating and cooling stages in these high-temperature susceptibility measurements. High-temperature susceptibility measurements were used to assess whether the minerals responsible for magnetization in the rocks underwent any changes due to temperature, to determine the Curie temperatures, and to understand the domain structure. For this aspect of the study, 23 sites representing various ages and types of rocks were chosen for high-temperature susceptibility studies. It can be said that some rocks are rich in "Ti-Magnetite". It is observed that mineral phase transformation occurs in some rocks as a result of heating phases.This study was supported by the project of the Scientific Research Projects Commission of Gümüşhane University with Project Number: 21.B0126.01.01.
A comprehensive inventory of large hydropower systems in the Italian Alpine Region
Authors: Zarghami Dastjerdi Soroush , Galletti Andrea , Majone Bruno
Published: March 2024

The threat of climate change and water resource overexploitation to river network ecosystems and their natural flows is evident, particularly in mountainous regions where hydropower production is also responsible for significant alterations of the natural streamflow. Hydrological modeling in these watersheds is hindered by limited knowledge of technical and geometrical information. Key characteristics and parameters related to hydropower operating schedule and their hydraulic infrastructures are usually hard to obtain as they are mostly confidential data producers hold. Consequently, modeling hydropower systems over large domains often relies on simplified methods which may decrease the reliability of these studies. In response to these challenges, we created a comprehensive inventory designed to model the interaction between natural stream networks and hydropower-related infrastructures at the mesoscale. This inventory, tailored for the large hydropower systems in the northern mountainous region of Italy (Italian Alpine Region - IAR), includes detailed hydraulic parameters essential for the reliability of water-energy-nexus modeling implementations. The selected region includes over 300 large hydropower systems with complex infrastructures, among those, nearly 160 plants are reservoir-fed, causing a significant alteration in streamflow. To assess the reliability of the provided inventory, we employed HYPERstreamHS as the reference hydrological model. We assessed the accuracy of our designed inventory by comparing the modelled hydropower production with the finest observations available, which are province-aggregated monthly hydropower production data from 1995 to 2008. The outcomes revealed a commendable similarity ranging from 83% to 100% across simulated areas, with an overall average of 90%, solidly confirming the accuracy of the crafted inventory.
The evolution of fault networks during multiphase deformation: An analogue modeling approach
Authors: Liu Jun , Rosenau Matthias , Kosari Ehsan , Brune Sascha , Zwaan Frank , Oncken Onno
Published: March 2024

It is well known that triaxial deformation is a common feature of continental tectonics, and is accommodated by complex polymodal fault networks. Field investigations confirm that multiple phases involving time-dependent three-dimensional strain conditions (e.g. constriction, plane, and flattening strain) affect the spatial and temporal interaction of polymodal fault systems. However, a key question remains: How do changing strain conditions affect the reactivation of fault systems that formed during a previous deformation phase? Here, we conduct scaled analogue models with time-dependent boundary conditions to investigate how fault networks evolve under changing boundary conditions, including  reactivation and formation of new faults.We have developed a setup in which a basal rubber sheet is stretched in one direction, so that longitudinal extension and layer thinning are accompanied by lateral shortening, hence producing triaxial deformation (Liu et al. in revision). According to previous brittle-viscous experiments with this set-up, an increase in longitudinal extension velocity results in a higher coupling between the rubber base and brittle layer, generating increasing transmission of lateral shortening from the base into the brittle layer. We thus induce constriction-to-plane strain conditions in the brittle layer as a function of longitudinal extension velocity by varying the magnitude of lateral contraction. In a new set of experiments, by varying extension velocity either stepwise or continuously, we realize time-dependent kinematic boundary conditions including deformation phases and secular changes, respectively. Digital image correlation (DIC) and photogrammetry (structure from motion, SFM) are employed to track the 3D kinematic surface and topography evolution, respectively.Preliminary observations show both the formation of new faults and the reactivation of early phase faults through a change from plane to constriction strain. Conversely, a change from constriction to plane strain conditions results in the abandonment of the early phase fault network as it becomes overprinted by fault systems of the subsequent phase. Moreover, early-phase fault systems influence the propagation and linkage of fault populations in subsequent phases. Our analogue models highlight the impact of strain conditions on the overall plan-view geometry of fault populations, providing alternative explanations for complex fault patterns and interactions (e.g. the Jeanne d’Arc basin, the North Træna Basin, and the Beagle Platform).
Effects of the 2023 Kahramanmaraş Earthquake Sequence on the Palu Segment of the East Anatolian Fault
Authors: Hoşses Muhammed İbrahim , Özarpacı Seda , Özdemir Alpay , Ayruk Efe Turan , Turğut Muhammed , Farımaz İlay , Doğan Uğur , Ergintav Semih
Published: March 2024

The East Anatolian Fault (EAF) is an approximately 420 km long sinistral strike-slip fault extending between Karlıova (Bingöl) in the northeast and Türkoğlu (Kahramanmaraş) in the southwest. The earthquake in Sivrice (Elazığ) on January 24, 2020, with a magnitude of Mw 6.8, along with the earthquakes in Pazarcık (Kahramanmaraş) on February 6, 2023, with a magnitude of Mw 7.8, and Elbistan (Kahramanmaraş) with a magnitude of Mw 7.6, has increased the seismic potential of the left-lateral strike-slip East Anatolian Fault.This study involved a total of 12 campaign measurements conducted at a GNSS network consisting of six sites in Palu (Elâzığ) segment of EAF  between the years 2015 and 2023. The distance of the survey GNSS sites and continuous GNSS stations from the fault varies between approximately tens of meters to hundred of kilometers. Before and after the earthquakes on February 6, 2023, near field GNSS data were utilized in the analysis of crustal movements related with  the earthquakes in 2020-2023. The estimated deformation in the GNSS network campaign results between September 2021 and September 2023, varies from approximately 10 ± 2.6 mm to 40 ± 2.9 mm in Palu segment. These estimations include not only the postseismic effects of the 2020 Sivrice (Elaz) earthquake, but also the coseismic and early postseismic effects of the 2023 Kahramanmaraş earthquake sequence, along with ongoing shallow creep observations.
Long-term geophysical monitoring of safety critical geotechnical infrastructure slopes
Authors: Chambers Jonathan , Wilkinson Paul , Meldrum Phil , Kuras Oliver , Swift Russell , Ngui Jason , White Adrian , Cimpoiasu Mihai , Harrison Harry , Maleki Rosa , Boyd James , Dashwood Ben , Bruce Edward , Donohue Shane , Holmes Jessica , Stirling Ross , Whiteley Jim , Binley Andrew
Published: March 2024

Robust and timely assessment of the condition of geotechnical infrastructure assets (e.g. cuttings, embankments, dams) is essential for cost effective maintenance and engineering interventions to prevent failure events. Infrastructure slopes (in transportation, utilities and water management) are experiencing increasingly high levels of failure and require considerable resources to maintain; in the order of hundreds of millions of pounds per year in the UK alone. The issue of accelerating asset deterioration is being exacerbated by the greater prevalence of extreme weather events. Conventional monitoring techniques are still dominated by surface observations, which provide infrequent information and deliver very few insights into subsurface deterioration processes which typically precede surface expressions of deterioration. Here we describe the development of novel geoelectrical imaging technology to monitor and assess the internal condition of infrastructure slopes in four-dimensions. In particular, we outline a workflow in which time-lapse geophysical models are used to inform estimates of soil moisture and suction distributions, and we consider the challenges associated with the deployment of geophysical monitoring systems on operational geotechnical assets. Examples are given from long-term field experiments on transportation and water management earthworks. We propose that novel geophysical monitoring complements more traditional forms of asset assessment to significantly enhance the resilience of safety critical infrastructure through improved subsurface information provision and decision support.
Thermal impact on shallow groundwater systems by heat loss from hot wells: the impact of operational conditions and subsurface heterogeneity
Authors: de Vries Enno , Hartog Niels
Published: March 2024

Geothermal heat production and aquifer thermal energy storage have significant potential to contribute to the energy transition. However, due to higher temperature inside the wells used, it is known that this leads to heat loss through conduction to the surrounding cooler, shallower groundwater systems. Therefore it is important to be able to anticipates such impacts to allow effective monitoring and prevention or mitigation measures when needed. However the thermal impact on groundwater systems is expected to strongly depend on local conditions. Therefore, this study focused on the impact of operational conditions (e.g. effective well temperatures and intermittency) and aquifer conditions (e.g. permeabilities and heterogeneity) on the resulting heat transport processes into the aquifer by conduction and density driven flow. To evaluate the degree and variation of impact that may occur under field conditions, the heat loss to a shallow groundwater system was simulated using a 2D axisymmetric numerical MODFLOW 6 model for a wide range of conditions considering both the impact of conduction and density-driven flow. The results of this study indicate that the total thermal impact and its distribution (up to >10 m from the hot well in 10 years) in shallow groundwater systems is strongly impacted by the induced density driven flow in the relatively permeable layers of the groundwater system. Conduction is dominant in transfer of heat from the hot well in the low permeability confining layers and for mitigating temperature differences in the groundwater system induced by buoyancy flow. Overall, this study highlights the importance of considering local conditions in assessing thermal impact by heat losses from hot well casings, to allow distinguishing these thermal impacts from those induced by leakage and to allow efficient thermal groundwater impact monitoring.
Towards a 500 kyr record of tropical land temperature from fluid inclusion microthermometry in Borneo speleothems
Authors: Meckler Anna Nele , Krüger Yves , Løland Marit H. , Ding Hao , Afonso Camille , Hof Verena , Carolin Stacy , Timmermann Axel
Published: March 2024

The advent of nucleation-assisted fluid inclusion microthermometry in speleothems (Krüger et al. 2011) opens new opportunities for accurate and precise reconstructions of land temperature in low latitudes. This physical approach, based on determination of liquid-vapor homogenization temperatures in fluid inclusions, does not need empirical calibration. Typical standard errors of the mean (2 SEM) resulting from measurements of 30-40 coeval fluid inclusions range between ~0.2 and 0.5 °C. In addition, the approach offers the rare opportunity to derive mean annual temperatures not affected by seasonal biases, due to year-round stable temperatures in the caves. However, the technique is limited to warm caves with temperatures above ~10°C and poses strict requirements on the samples in terms of calcite fabric and abundance and size of fluid inclusions.Northern Borneo (4°N, 115°E) is situated in the heart of the Indo-Pacific Warm Pool, a major heat engine of the climate system. From this region, a set of well-dated speleothems covering the last half million years has previously been studied for hydroclimate reconstructions (Partin et al., 2007, Meckler et al., 2012, Carolin et al., 2013, Carolin et al. 2016). We are now revisiting these samples to generate a continuous land temperature record from this key area. Our data so far cover the last glacial termination (Løland et al., 2022) and several other terminations, interglacials, and glacials. We find glacial-interglacial changes in cave temperature of 4.4-5.4 °C, which reduce to 3.6-4.7 °C when correcting for sea-level induced changes in cave altitude. This amplitude is substantially larger than predicted by a transient Pleistocene simulation with CESM1.2 (Yun et al., 2023), suggesting either amplifying local factors not included in the model or a more general underestimation of the sensitivity of tropical temperatures to greenhouse and orbital forcing. The temporal evolution of Northern Borneo temperature for the most part follows the evolution of atmospheric CO2, as previously observed with marine records, but with notable exceptions where insolation forcing appears to be the dominant factor. Our evolving temperature record thus sheds new light on the role and response of one of the major players in the climate system during glacial-interglacial cycles. References:Carolin, S.A., et al., 2013. Science 340, 1564–1566.Carolin, S.A., et al., 2016. EPSL 439, 182-193.Krüger, Y., et al., 2011. Chem. Geol. 289, 39-47.Løland, M.H., et al., 2022. Nature Communications 13: 5158.Meckler, A.N., et al., 2012. Science 336, 1301–1304.Partin, J.W., et al., 2007. Nature 449, 452–453.Yun, K.-S., et al., 2023. Clim. Past, 19, 1951–1974. 
Groundwater storage trends in northern Italy as observed by GRACE, well measurements, and vertical land motion
Authors: Carlson Grace , Massari Christian , Rotiroti Marco , Preziosi Elisabetta , Bonomi Tullia , Wilder Andrew , Werth Susanna , Whitaker Destinee , Wang Tianxin , Cowherd Marianne , Girotto Manuela
Published: March 2024

Geodetic observations of the Earth’s gravitational and deformational response to changes in terrestrial water storage (∆TWS) have been essential measurements to identify regions experiencing long-term wetting and drying driven by a combination of climate and anthropogenic forces. The northern Italian Plains, home to a third of the country’s population and contributing more than half of the agricultural output, have experienced a dryer-than-normal two decades. Here, we investigate what impact these dry conditions have on the long-term groundwater storage (GWS) using observations of change in terrestrial water storage (∆TWS) from the Gravity Recovery and Climate Experiment (GRACE) and the second-generation follow-on (GRACE-FO) missions and in-situ groundwater level time series from 820 wells over the period of 2003-2022. We use a wavelet time-frequency analysis to deconstruct each signal into seasonal and long-term components and identify multi-year dry and wet epochs. We find two long periods of declining groundwater storage (2003-2007, 2015-2022), two short periods of groundwater recovery (2008-2009, 2012-2014), and one period of near-zero ∆GWS (2010-2011). We find a net volume loss of 12.0 km3 from 2003-2022. Further, we validate these ∆GWS trends and total volume loss estimates using a combination of in-situ groundwater level variations and vertical land motion observed at nearly 500 Global Navigation Satellite System (GNSS) stations. These stations show poroelastic deformation over aquifers related to groundwater storage changes and elastic loading deformation that is highly correlated with predicted elastic loading displacements from GRACE(-FO) ∆TWS outside of aquifer areas. To calculate groundwater storage from groundwater level, we estimate spatially- and depth-variable aquifer storage coefficients using a combination of lithologic information and co-located well and GNSS observations. By analyzing all three datasets in combination we can evaluate the impacts of multi-year dry- and wet- periods on groundwater resources, providing essential contextual information for future water management.
Linking material cycles and ecosystem services assessment in forest modelling
Authors: Song Cholho , Lim Chul-Hee , Ko Youngjin , Son Jiwon , Choi Hyun-Ah , Lee Woo-Kyun
Published: March 2024

In ecosystem services assessment in South Korea, many studies have applied various modelling methods. However, these modelling approaches mainly focused on the statistical growth model based on the national forest inventory, so calculating carbon was the main target of research. Statistical modelling enables annual assessment of the carbon budget in forests, but it was limited to understanding daily ecosystem changes and other material cycles. Therefore, this study tried to set up the linkage of material cycles and ecosystem services using various current modelling schemes in South Korea. Therefore, the process-based model and current forest models were applied to assess carbon and ecosystem productivity. In addition, their possible linkage to ecosystem services was analyzed. From the process-based model, the net primary productivity value was calculated at around 5.17 Mg C ha-1 average, and it indicated around 1.61 Mg C ha-1 in net carbon sequestration during the 2021-2100. Considering the current projection of annual carbon sequestration, this value is similar to the current model projection. In addition, the process-based model calculated evapotranspiration, respirations, and other values which converted ecosystem services, especially climate regulation, supporting ecosystem services, and provisioning ecological materials. Linkage of these models can support to assessment of many other non-assessed ecosystem services, and an ensemble of modelling and expanded modelling in ecosystem services will be required to assess Korean ecosystem services.
Advances in clumped isotope measurements of nitrous oxide by laser spectroscopy
Authors: Magyar Paul , Prokhorov Ivan , Brunamonti Simone , Chénier Noémy , Emmenegger Lukas , Tuzson Béla , Mohn Joachim
Published: March 2024

Nitrous oxide (N2O), a greenhouse gas and ozone-depleting molecule with a 116-year atmospheric lifetime, is accumulating in the atmosphere at an accelerating pace. While it is known that the conversion of anthropogenic nitrogen pollutants to N2O by the environmental nitrogen cycle predominately drives this accumulation, essential questions remain regarding the spatial and temporal balance of N2O production and consumption. Stable isotope measurements of δ15N, δ18O, and 15N site preference (SP) in N2O provide valuable constraints on its sources and sinks. Given the complex array of nitrogen cycle processes and their overlapping isotopic signatures, they are often not sufficient to deconvolve them completely. The ‘clumped’, or multiply-substituted, isotopologues 14N15N18O, 15N14N18O, and 15N15N16O provide three additional independent constraints on N2O sources and processing, with potential to provide insight into source partitioning and reaction mechanisms.Spectroscopic approaches have emerged as central tools for quantification of N2O isotopes in atmospheric and environmental samples due to their sensitivity, suitability for continuous or on-site measurement, and isotopologue-specificity. We present an updated approach to the measurement of the eight most abundant isotopic variants of nitrous oxide, including these rare clumped isotopologues, using a quantum cascade laser absorption spectrometer with a 36 m multipass cell. A dual-laser system offers the opportunity to choose a pair of spectral windows that contains strong ro-vibrational absorption lines of the rarest isotopologues, enabling precise clumped isotope ratio measurements on relatively small (
Gridded data of daily atmospheric precipitation and minimum, mean and maximum air temperature for Ukraine, 1946-202
Authors: Osadchyi Volodymyr , Skrynyk Oleg , Sidenko Vladyslav , Aguilar Enric , Guijarro Jose , Szentimrey Tamás , Skrynyk Olesya , Palamarchuk Liudmyla , Oshurok Dmytro , Kravchenko Igor , Kyreyeva Zoryna , Pinchuk Dmytro
Published: March 2024

In this contribution, we present the results of the development of long gridded climate time series, which cover the territory of Ukraine for the period of 1946-2020 (75 years). The spatial resolution of the developed data is 0.1o×0.1o (approximately 10 km in both longitude and latitude directions), while their time discreteness is 1 day. Four essential climate variables are included in the dataset, namely daily sums of atmospheric precipitation and daily minimum, mean and maximum air temperature. The created gridded product is based on the complete collection of weather measurements, performed at 178 meteorological stations of Ukraine, which constitute the modern national observation network. Quality assurance check, homogenization and gridding of the station time series were performed by means of widely used and well approved climatological software, i.e. INQC, Climatol and MISH, respectively. The produced gridded time series were statistically compared on the monthly and daily time scales with several existing data sets, which have the same spatial resolution (i.e., previously developed gridded monthly data of Ukraine, ERA5-Land, E-OBS). The comparison showed good accordance with UA monthly data (partly obtained from other paper sources than the daily data) and acceptable agreement with ERA5-Land and E-OBS data. The developed long gridded time series are of great importance as they were built with the involvement of as many real weather measurements as possible. Therefore, they can be used as a reference for a wide variety of climatological applications for the territory of Ukraine. Oleg Skrynyk acknowledges the support from the MSCA4Ukraine fellowship program, which is funded by the European Union.