bluuebunny/crossref_metadata_2025 huggingface dataset:
Community-based lightning detection in Europe: studying the detection efficiency of the BlitzOrtung network - a case study concerning lightning climatology over Hungary
Authors: Buzás Attila , Bozóki Tamás , Bór József
Published: February 2023

Being one of the natural hazards and an indicator of severe weather, studying and evaluating lightning activity has a well recognized role in scientific research. The detection of lightning activity with a good efficiency is crucial not only to the protection of human lives and minimizing economic losses, but to get a better understanding of Earth’s climate system as well.There are several solutions for lightning detection implemented both on ground (e.g., Earth Networks, EUCLID, LINET, WWLLN, etc.) and in space (e.g., GLM, LIS, OTD) providing a big amount of reliable data. The BlitzOrtung (BO) is a dynamically developing and community-based lightning detection network (Wanke et al., 2014). By 2018, the BO had circa 2000 stations around the globe (Narita et al., 2018) and their data are used widely in Europe. However, there is a need to evaluate the detection efficiency and compare the parameters of the detected lightning strokes with the ones derived from other networks (Narita et al., 2018).In this study, we aim at evaluating the performance of the BO network on a statistical basis. First, the detected lightning strokes are paired with those reported by the LINET and WWLLN systems using the time point and location information. Then the geographical distribution as well as the temporal stability of the number of detected events and the percentage of paired events are examined. The first results of a pilot analysis over Hungary (45.5°-49° N, 16°-23° E) in Central Europe will be presented. This project serves to establish a comparison-based method for the evaluation of the lightning climatology of a region. Narita, T. et al. (2018): A study of lightning location system (Blitz) based on VLF sferics, 34th International Conference on Lightning Protection, 978-1-5386-6635-7/18/$31.00,Wanke, E., Andersen, R., and Volgnandt, T. (2014): A World-Wide Low Cost Community-Based Time-Of-Arrival Lightning Detection and Lightning Location Network, http://www.blitzortung.org/Documents/TOA_Blitzortung_RED.pdf
Studying secondary ice production mechanisms: from a remote sensing and hydrometeors dynamics perspective
Authors: Le Roy De Bonneville Florian , Aboel Fetouh Yasmin , Cermak Jan , Hoose Corinna , Järvinen Emma , Leisner Thomas , Uhlmann Markus
Published: February 2023

Ice crystal number concentrations were often found to be orders of magnitude higher than the number concentration of ice nucleating particles; a finding that indicated the presence of secondary ice production (SIP).  Although 6 mechanisms of SIP have been both discovered and theorized, it is still not fully understood and the recent studies have been inconclusive in identifying the dominant process in real conditions.  This lack of constraint of ice multiplication adds to the uncertainty of cloud simulations in climate models. Studying SIP is challenging due to the various interfering factors involved.In this study, we attempt to further our knowledge in understanding the SIP mechanisms using two different but complementary approaches. The first consists of using remote sensing tools such as Himawari-8 and MODIS retrievals in addition to the SOCRATES in-situ data to identify the presence of SIP and categorize the possible mechanism involved.The second approach utilizes numerical simulations to further understand these mechanisms that are potentially responsible for SIP, but through the study of the dynamics of the different particles (ice crystals, supercooled droplets, graupel...) involved in these processes. In this approach we focus on the characteristics of the particles, such as their diameter and concentration, as well as the presence of turbulence, that are crucial in describing their movement and the feasibility of the mechanisms under study. 
Verification of ECMWF SEAS5 precipitation seasonal forecasting using ERA5 and observations for Brazilian Hidro Power Plants
Authors: Rogiski da Silva Nathalli , Bomfim da Silveira Reinaldo , Freitas Camila , Silmara Aver Paranhos Cassia , Luiz de Campos André , Ávila Rangel Leandro
Published: February 2023

The Electric Energy Company of Parana (COPEL GeT), the Meteorological System of Parana (SIMEPAR) and RHAMA Consulting company are undertaking the research project PD-6491-0503/2018 for the development of a hydrometeorological seasonal forecasting for Brazilian reservoirs. The project, sponsored by the Brazilian Electricity Regulatory Agency (ANEEL) under its research and development programme, aims the forecasting of streamflow, at temporal scales ranging from 1 to 270 days, at hydro power enterprises, which are integrated by the National Power System Operator (ONS) through its Interconnected System (SIN). In the present work, we verify the precipitation seasonal product from SEAS5 from ECMWF against three references, namely model climatology, ERA5 reanalysis and in-situ observations. In order to achieve the results, we extract the values from the model, respectively to the closest location of observations within Brazilian rain gauge network, corresponding to hydro power plants, and compare them to the observed values and ERA5 results, for the period from 2000 to 2020. The accuracy measurement was performed by settling a contingency matrix to estimate the probability of detection (POD), probability of false detection (POFD), the ROC curve, the area under the ROC (AUC) and other related metrics. The statistics are gathered by monthly and by season and by considering three quantile thresholds of rainfall distribution for forecasting, computed for 153 reservoirs of the SIN. The results describe a good performance of SEAS5 for either monthly or seasonal forecast if compared to climatology or ERA5, but less accuracy if compared to the rain gauges, mainly for low quantiles. Despite this, by considering the large extension of the country and its climate diversity, we noticed the SEAS5 is quite promising for using on hydrological forecasting at seasonal scale.
Investigating the effects of meteorological conditions on landslide formation in a high-arctic glacier basin using terrestrial laser scanning (Ny-Ålesund, Svalbard)
Authors: Kuschel Erik , Zangerl Christian , Laa Ursula , Klaus Vinzent , Prokop Alexander , Bernard Eric , Friedt Jean-Michel , Duvernet Léo , Tolle Florian
Published: February 2023

Landslide processes are one of the dominant agents of erosion and sediment transport in alpine terrain, which often pose a significant risk to communities and infrastructure around the world. Climate change generates a wide range of processes such as glacier retreat, permafrost degradation or changing precipitation patterns, which are projected to decrease the stability of mountain slopes and thus will lead to increased landslide activity. However, the empirical evidence is lacking as meteorological boundary conditions altered by climate change, may have different and often contrasting effects on landslide formation and activity. As a result of the Arctic amplification, high-arctic environments are an important field laboratory for investigating current and future landslide processes.The ongoing paraglacial response of sediment-mantled slopes through landslide processes has been assessed and mapped around the globe. However, investigations on the impact of meteorological factors on shallow landslide formation modifying sediment-mantled slopes in the surroundings of retreating glaciers is in many cases not possible due to the lack of long-term high-resolution terrain data. The Austre Lovénbreen glacier basin in Svalbard (Norway) is a particularly relevant location to study the modification of slopes through landslides, as the area has been affected by the recent global warming characterized by the greatest temperature increase during the last three decades.The objectives of this study are i) to provide data utilizing multi-temporal high-resolution terrestrial laser scans of the glacier and the surrounding slopes, ii) identify and quantify landslide processes found on sediment-mantled slopes, iii) investigate failure mechanisms and derive a conceptual model describing the adaptation of the periglacial talus slopes to the retreat of the glacier and iv) investigate the driving factors for the temporal and spatial evolution of landslides in the Austre Lovénbreen Basin.The Austre Lovénbreen glacier basin represents a highly dynamic environment, which is in an unstable state, caused by the rapid retreat of the glacier and by climatic conditions. We show that, in contrast to the established literature, shallow debris slides are the primary source of sediment transport on steep sediment-mantled slopes in a high-arctic environment and that meteorological parameters control their spatial and temporal evolution.
Hamiltonian Monte Carlo Method and Symplectic Geometry
Authors: Öztürk Feyza , Diner Çağrı , Aktar Tevfik Mustafa
Published: February 2023

Hamiltonian Monte Carlo (HMC) method is an application of non-Euclidean geometry to inverse problems. It is a probabilistic sampling method with the basis of Hamiltonian dynamics. One of the main advantages of the HMC algorithm is to draw independent samples from the state space with a higher acceptance rate than other MCMC methods. In order to understand how a higher acceptance rate is achieved, I have studied HMC in the light of symplectic geometry. Hamiltonian dynamics is defined on the phase space (cotangent bundle), which has a natural symplectic structure, i.e. a differential two-form that is non-degenerate and closed.Symplectic geometry lies at the very foundations of physics: Geometry is the method of abstracting the solutions of physical phenomena. Once the use of phase space in the solutions of mechanical systems (e.g. simple harmonic motion, or ray-tracing) is abstracted via geometry, then it can be used in other branches such as optimization problems (e.g. Hamiltonian Monte Carlo). I present two different applications of symplectic geometry: Ray-tracing and Hamiltonian Monte Carlo.First, the Hamiltonian function is defined on the phase space, which corresponds to an invariant of the system (e.g. total energy for the HMC method and wavefront normal for ray-tracing problem), and then by using the non-degeneracy property, a vector field can be found in which Hamiltonian function is invariant along the integral curves of the field. The invariance of the Hamiltonian function results in a high acceptance rate, where we apply the accept-reject test to satisfy the detailed-balance property.After describing the concept of phase space for both mechanical systems and optimization problems, I am going to show different applications of HMC, including 2-dimensional travel-time tomography on a synthetic complex velocity structure. 
Forecast sensitivity to the assimilation of observational data - two case studies for Australia
Authors: Rogers Cassandra , Tingwell Chris
Published: February 2023

Australian weather forecasts use Numerical Weather Prediction (NWP) model output. Forecast accuracy is improved by assimilating a range of observational data which includes Australian Bureau of Meteorology station data. The significant investment by the Bureau of Meteorology in the national observing network, and the constant evolution of observational technologies, requires an ongoing assessment of the scientific value of the network components. Examining an objective measure of the impact of each assimilated observing system on the quality of short-term NWP forecasts can potentially guide planning and investment decisions related to network efficiency and effectiveness. 

Traditional techniques for assessing the impact of observations in NWP are inflexible (i.e. they require dedicated trials) and computationally expensive, but a widely used technique, known as adjoint-based Forecast Sensitivity to Observations (FSO), can provide forecast impact information continuously, flexibly, and in near real-time. We use archived FSO data to assess the relative forecast impact of in-situ data for different instruments and variables. We use two case studies to examine the impact of 1) three upper-air measurement instruments - radiosondes, aircraft, and a wind profiler - through the atmosphere at Sydney Airport, and 2) Automatic Weather Station surface observations along the Great Barrier Reef. These studies aim to provide network planners with information that can guide observations rationalisation decisions. 
Comparing river routing concepts in distributed hydrological modeling
Authors: Bouaziz Laurène , Buitink Joost , van Verseveld Willem , Eilander Dirk , Hegnauer Mark , Sprokkereef Eric , Stam Jasper , van der Sleen Niek , Lammersen Rita
Published: February 2023

Distributed hydrological models are valuable tools for operational and strategic water management planning. These models include a representation of vertical processes such as interception, transpiration and infiltration and require a lateral component to route the water downstream along the river network. The kinematic wave is a commonly used approach for lateral flow in distributed hydrological models, which assumes that topography mainly controls the water flow. While this applies in steep terrain, the assumptions of the kinematic wave do not apply in flatter landscapes. The Wflow framework is a free and open-source distributed hydrological modeling platform developed by Deltares (van Verseveld et al., 2022). The Wflow framework has been extensively tested in catchments around the world using the SBM vertical concept in combination with the kinematic wave for lateral river, overland flow and subsurface flow routing. Recently, the local inertial approximation, which only neglects the convective acceleration term in the Saint-Venant equations, was implemented in the Wflow framework as an alternative lateral routing concept to accurately represent river routing processes in flatter areas. In addition, the numerical scheme proposed by de Almeida et al. (2012) was implemented for the simulation of 2D overland flow. Using the HydroMT (Hydro Model Tools, https://github.com/Deltares/hydromt) Python package, we set-up wflow_sbm models for the Rhine and the Meuse basins and compare alternative concepts for river (and overland flow) routing, including kinematic wave, local inertial 1D and local inertial 1D2D. The results show significant differences in the shape and magnitude of modeled peak flows and the importance of floodplain storage and floodwave attenuation processes, as the local inertial 1D2D simulations were closest to streamflow observations. With this study, we stress the importance of including relevant routing processes (floodwave attenuation through overbank flow in the floodplains) as opposed to a more extensive calibration which would compensate for these lacking processes. References:de Almeida, G. A. M., P. Bates, J. E. Freer, and M. Souvignet, 2012, Improving the stability of a simple formulation of the shallow water equations for 2-D flood modeling, Water Resour. Res., 48, W05528, https://doi.org/10.1029/2011WR011570.van Verseveld, W. J., Weerts, A. H., Visser, M., Buitink, J., Imhoff, R. O., Boisgontier, H., Bouaziz, L., Eilander, D., Hegnauer, M., ten Velden, C., and Russell, B.: Wflow_sbm v0.6.1, a spatially distributed hydrologic model: from global data to local applications, Geosci. Model Dev. Discuss. [preprint], https://doi.org/10.5194/gmd-2022-182, in review, 2022.
Sulfur and carbon isotope measurements of carbonyl sulfide (COS) from small air samples; an overview and recent findings
Authors: Baartman Sophie , Krol Maarten , Röckmann Thomas , Popa Maria Elena
Published: February 2023

Carbonyl sulfide (COS) is the most abundant sulfur-containing trace gas in the atmosphere, with an average mixing ratio of 500 parts per trillion (ppt). It has a relatively long lifetime of about 2 years, which permits it to travel into the stratosphere. There, it likely plays an important role in the formation of stratospheric sulfur aerosols (SSA), which have a cooling effect on the Earth’s climate. Furthermore, during photosynthetic uptake by plants, COS follows essentially the same pathway as CO2, and therefore COS could be used to estimate gross primary production (GPP). Unfortunately, significant uncertainties still exist in the sources, sinks and global cycling of COS, which need to be overcome. Isotopic measurements of COS could be a promising tool for constraining the COS budget, as well as for investigating its role in the formation of stratospheric sulfur aerosols.Within the framework of the COS-OCS project, we developed a GC-IRMS based measurement system at Utrecht University that can measure δ33S, δ34S and δ13C from S+ and CO+ fragment ions of COS from small air samples of 2 to 5 L. With this system, we have measured various types of air samples, including outside air, firn air from Greenland, and air from the upper troposphere – lower stratosphere region. We conducted photosynthesis experiments using a plant gas exchange chamber and we are also planning to measure firn air from Antarctica. Here, we will present an overview of the COS isotope measurements conducted within the COS-OCS project, and we will highlight the most interesting findings.
QA4SM: a service for transparent and reproducible evaluation of satellite soil moisture products
Authors: Aberer Daniel , Preimesberger Wolfgang , Stradiotti Pietro , Scherrer Samuel , Tercjak Monika , Gruber Alexander , Dorigo Wouter , Boresch Alexander , Himmelbauer Irene , Gibon François , Richaume Philippe , Mialon Arnaud , Kerr Yann , Mahmoodia Ali , Crapolicchio Raffaele , Sabia Roberto , Garcia Raul , Goryl Philippe , Scipal Klaus
Published: February 2023

Quality assessment is an integral part of creating climate data records. Producers of satellite based records want to evaluate whether their products fulfill certain quality requirements, such as the ones set by the Global Climate Observing System (GCOS) of the World Meteorological Organization (WMO) or by the Committee on Earth Observation Satellites (CEOS). Users of these data, on the other hand, are usually interested in their fitness-for-purpose in terms of specific applications, temporal/spatial subsets, and how different data sets of the same variable compare to each other.Quality Assurance for Soil Moisture (QA4SM) is an online validation service for (inter)comparing soil moisture records and assessing their quality, incorporating best practices, in a standardized, traceable way via an easy-to-use graphical user interface. The processing chain includes automatic preprocessing (filtering, temporal/spatial matching, scaling) of input data and computation of a set of quality metrics (e.g., correlation, bias, signal-to-noise-ratio). It provides an open and flexible framework in which users can upload their own data for comparison to state-of-the-art records that are already integrated in the service. These include reference data from the International Soil Moisture Network (ISMN), reanalysis data from ERA5 and GLDAS Noah, and various satellite based records such as SMOS, SMAP, Sentinel-1, ESA CCI, and C3S. In this presentation we give insight into the scientific and technical background of developing a cloud-based validation service and its current capabilities. We explain the advantages a service like this has, and how it can benefit users of climate data records with minimal effort.The service was launched as part of the Quality Assurance for High Spatial and Temporal Resolution Soil Moisture Data (QA4SM-HR) project through the Austrian Research Promotion Agency (FFG) and is currently developed within the framework of the European Space Agency’s Fiducial Reference Measurement for Soil Moisture (FRM4SM) project. It can be accessed at: https://qa4sm.eu
Observations of Sea Ice Melt and Ice-Ocean Boundary Layer Heat Fluxes in the Marginal Ice Zone North of Fram Strait
Authors: Reifenberg Simon F. , von Appen Wilken-Jon , Fer Ilker , Haas Christian , Hoppmann Mario , Kanzow Torsten
Published: February 2023

Given the prospect of a merely seasonally ice-covered Arctic Ocean in the future and a consequential new quality of atmosphere-ocean coupling, understanding and quantifying oceanic processes that contribute to sea ice melt is of particular relevance.A region of intense melting is the marginal ice zone (MIZ) north of Fram Strait, where inflowing warm Atlantic Water meets sea ice advected southward by the Transpolar Drift. We present observations of the ice-ocean boundary layer (IOBL) from a cruise of German research vessel Polarstern to that region in summer 2022, where we gathered continuous-in-time hydrographic observations from autonomous drifting stations on three separate ice floes, supplemented by intense observation periods of vertical microstructure profiles and ice cores from crewed stations during three revisits per floe throughout the drifting period.The three occupied floes were oriented on a line approximately perpendicular to the ice edge, initially about 25 km apart from each other, with the southernmost floe located 75 km away from the edge. The drifting instrument platforms cover a common time period of approximately two weeks, under relatively quiescent atmospheric conditions. First results show that, while the floes exhibited similar drift trajectories dominated by superimposed diurnal and semidiurnal oscillations, the evolution of key IOBL variables, such as stratification, melt rates, friction velocity, and turbulent fluxes, varied considerably – both in time and among the occupied floes.We plan to assess how this observed variability relates to other measured properties of sea ice (e.g., ice roughness, ice thickness distribution, floe size distribution) and of the upper ocean (e.g., ice-ocean velocity shear, turbulence, surface waves, internal waves and tides) and their interaction, in order to put our preliminary findings into the broader context: ocean controls on sea ice melt in the marginal ice zone north of Fram Strait.
Characterization of size-segregated particles turbulent fluxes in an Arctic city (Fairbanks, Alaska)
Authors: Pappaccogli Gianluca , Donateo Antonio , Scoto Federico , Busetto Maurizio , Pohorsky Roman , Baccarini Andrea , Schmale Julia , Barret Brice , Bekki Slimane , Brett Natalie , Law Kathy S. , Dieudonné Elsa , Fochesatto Gilberto J. , Simpson William , D'Anna Barbara , Temime-Roussel Brice , Decesari Stefano
Published: February 2023

Wintertime air pollution affects air quality of Arctic and sub-Arctic urban areas, because of the coupling between strong local emissions for residential heating and energy production and poor atmospheric dispersion associated with a stratified planetary boundary layer. Aerosols represent priority pollutants in such environments, and their behaviour in the Arctic wintertime boundary layer not only impacts air quality but also determines deposition on snow or ice surfaces, leading to chemical and physical modifications in the snowpack. The interactions between boundary layer meteorology and air pollution were the focus of the international ALPACA (Alaskan Layered Pollution and Chemical Analysis) field campaign held in January and February 2022 in Fairbanks (AK, USA). The aim of the present work is to analyse the fluxes of atmospheric particles in at a urban background site in Fairbanks, based on continuous observations of aerosol concentration, size distributions, and size-segregated deposition velocities. The EC system was installed at the suburban site of UAF (University of Alaska Farm), located nearby the foothills bordering the city basin. The main micrometeorological parameters and fluxes (wind field, friction velocity, turbulent kinetic energy, and sensible heat flux) were characterized in terms of boundary layer conditions (occurrence of thermal inversions, dynamic stratifications, vertical wind shear, slope currents, coherent turbulence structures). The aerosol eddy covariance system was based on a condensation particle counter (CPC) - able to measure particles down to 5 nm in diameter - and an Optical Particle Counter Optical Particle Counter (OPC) for evaluating particle fluxes in the accumulation mode (0.25 < dp < 0.8 μm) and quasi-coarse mode (0.8 < dp < 3 μm). The median number concentration was 13 E+3 cm−3, 76 cm−3 and 0.3 cm−3 for ultrafine, accumulation and quasi-coarse particles mode, with higher concentrations found at low wind speeds. The particle fluxes showed a net emission pattern for the ultrafine, accumulation and quasi-coarse dimensional mode, especially in daytime, with average values of 203, 0.3, and 0.02 cm-2 s-1 respectively. Deposition periods were observed most frequently for air masses from the city located to the east, while local emission sources due to traffic lead emission fluxes, especially in the accumulation mode. We discuss the particle flux measurements in the context of parallel aerosol and gaseous pollutants determined by fixed and mobile platforms (a tethered balloon and a car) as well as of determinations of depositions in the snow pack across the Fairbanks area.
Ecosystem structure changes following a marine megafaunal Pliocene extinction and the role of continental shelf habitat loss
Authors: Shipley Amy , Aze Tracy , Pimiento Catalina , Beckerman Andrew , Dunne Jennifer , Shaw Jack , Dunhill Alexander
Published: February 2023

The end of the Pliocene (~2.5-3 Mya) saw a period of biotic turnover in marine ecosystems with significant losses in marine megafauna (36% of genera globally) including the giant apex predator, Otodus megalodon. This recently identified extinction event coincided with a period of notable climatic change, with glaciation of the Northern Hemisphere causing a drop in global sea level. A positive correlation has been found between extinction probability and those genera that had high energy requirements and were associated with coastal, shelf habitats. As such, it has been hypothesised that these extinctions may have been driven by sea level drop resulting in loss of shelf area and a reduction in the neritic zone, a highly productive feeding habitat.Megafauna, and particularly apex predators, are known to play important trophic roles in extant communities yet the ecological consequences of losing these large taxa from marine ecosystems in currently not well understood. Using a trait-based inference model, we reconstructed food webs to assess the impact of this Pliocene extinction event on North Atlantic trophic community structure and dynamics. The model distributes trophic links using rules based on optimal foraging theory and functional traits assigned to every trophic species (e.g., body size, depth distribution and feeding habit). Through analysing the differences in food web topology pre- and post- megafaunal extinction event, we identify consistency in structure and connectedness between taxa within the webs. However, diversity changes within trophic levels and a decrease in competition in the Pleistocene indicates this turnover event did result in changes to the marine ecosystem makeup. Furthermore, our results show that the trophic role held by O. megalodon in the Pliocene appears to have been lost in the Pleistocene, with no other taxa taking its place.In addition to these findings, we also consider alternate hypotheses that may have impacted megafaunal extinction other than shelf loss. As the North Atlantic possesses areas of long continental shelf, neritic zone habitats may have only been shifted, not lost. Consequently, other factors may have played a more significant role.
Magma fluxes and magma emplacement depths are key to understanding the modes of plate divergence at slow and ultraslow spreading mid-ocean ridges
Authors: Cannat Mathilde
Published: February 2023

Plate divergence at mid-ocean ridges results from a combination of three main processes: magma emplacement, faulting and hydrothermalism. Melt fluxes at fast and most intermediate spreading ridges are high enough that the axial lithosphere (the plate between the plates) remains thin, or at least thinner than the cumulative melt thickness (melt flux divided by expansion rate) per unit length of ridge. In this configuration, the magma can fully accommodate plate divergence. This is not the case for slow and ultraslow ridges, where melt fluxes are lower, resulting in colder axial geotherms and an axial lithosphere that is in the general case thicker than the cumulative melt thickness per km of ridge. In this configuration, faults must accommodate a significant part of plate divergence, while magma may be emplaced at a range of depths, over the full thickness of the axial plate. This creates the conditions for the common exhumation of mantle-derived peridotites and the formation of a composite (variably serpentinized peridotites and magmatic rocks) oceanic crust. Melt fluxes, and probably melt emplacement depths, are also highly variable at slow-ultraslow ridges. This allows for complex interactions between magma and faults, and between magma and hydrothermal circulation, resulting in spatially and temporaly variable spreading modes (the combination of the mid-ocean ridge tectonic, magmatic and hydrothermal processes that determine the composition and structure of the oceanic lithosphere). In this presentation, I revisit these concepts, discuss the extent to which they have been tested by experiments and modelling, and point to several remaining questions.
Effect of stress cycling on the deformation and AE characteristics of reservoir rock from the perspective of energy storage: An experimental study
Authors: Naderloo Milad , Hernandez Edgar , Ramesh Kumar Kishan , Barnhoorn Auke , Hajibeygi Hadi
Published: February 2023

A successful energy transition requires effective storage options. Using underground energy storage (UES), such as depleted porous reservoirs, can help balance the production and demand for renewable energy. Because of the production and injection operations sequence, all underground energy storage systems, including compressed air and hydrogen energy storage, are subject to cyclic loading. To design and operate underground storage facilities, it is essential to understand the geomechanical behavior of porous reservoir rock under cyclic loading. We present the results of the triaxial cyclic laboratory experiments conducted on Red Phaelzer sandstone at 10 MPa confining pressure. By considering three frequencies (F1=0.014 Hz, F2=0.0014 Hz, and F1=0.0002 Hz), two amplitudes (A1=20 MPa and A2=5.9 MPa) and two stress regimes (38 MPa and 85 MPa), 12 triaxial cyclic tests were performed. In total, eight triangular stress cycles were applied for each test, and at the same time, six piezoelectric sensors recorded the acoustic emission (AE) activities during these experiments. Results showed that the total axial inelastic deformation increases when the stress regime and amplitude of cycles are increased. However, this parameter reduces by increasing the frequency of cycles. In addition, Young’s modulus computed from the loading ramps of the cycles increased significantly from the first cycle to the second cycle for all the tests. For tests in the brittle regime, the relation is that the larger the amplitude of cycles, the lower the increase in Young’s modulus. In addition, the AE analysis showed that major events were recorded in the first cycle. By increasing the number of cycles, the number of events, the maximum AE, and the average AE amplitude decreased. Our experimental results highlight that major mechanical changes and AE activities occur during the first cycle, and the stress regime influences the intensity of AE and mechanical changes. These outcomes can benefit studies about subsidence, uplift, fault reactivation, and other physical phenomena impacting the reservoir’s storage capacity, which is affected by cyclic sandstone deformation.
Coastal marsh resilience: a study on the role of bio-geomorphic self-organization
Authors: Hautekiet Sarah , Rossius Jan-Eike , Gourgue Olivier , Kleinhans Maarten , Temmerman Stijn
Published: February 2023

Tidal marshes are valuable coastal ecosystems that are threatened by global climate warming and the resulting sea level rise. Whether they drown or continue to exist, depends on the trapping of sediments that builds up the land surface. Tidal channel networks, which typically occur within tidal marshes, are the major supply routes for sediments towards the marshes and hence are expected to affect the capacity of marshes to keep up with sea level rise by sediment trapping. The development and evolution of tidal channel networks and the sediment trapping are locally determined by so-called bio-geomorphic interactions between plants, water flow and sediment transport. However, the effect of different environmental variables on channel network formation remains poorly understood. In this research, we investigated the impact of spatio-temporal plant colonization patterns by means of flume experiments. Four scaled landscape scale experiments were conducted in the Metronome tidal facility, a unique flume that tilts periodically to generate tidal currents. Two control experiments without vegetation, a third experiment with a channel-fringing vegetation colonization pattern, and a fourth with patchy vegetation colonization pattern. Seeds were distributed by water in the channel-fringing experiment, while a manual sowing method was used to obtain laterally expanding circular patches in the patchy experiment. Our results show that vegetation and their respective colonization pattern affect channel network formation both on a landscape scale and local scale. More extensive and effective channel networks are found in vegetation experiments. These results indicate that channel-fringing or patchy recruitment strategies might produce landscapes that are more resilient to sea level rise.
Understanding the effects land use and urban form on the urban heat island in Can Tho city, Vietnam 
Authors: Katzschner Antje , Nguyen Kieu Diem , Downes Nigel K.
Published: February 2023

Climate change and social-economic development are expected to compound climate changes risks. For southeast Asian cities, the occurrence of urban heat islands and extreme heat waves are a current and future concern for public health, well-being and household energy consumption due to increased cooling demands of urban residents and limited resources to cope. Urban heat island studies using remotely sensed imagery have already revealed that Vietnam’s major cities are characterized by strong temperature differences between urban and rural areas. As such implementing adaptation measures is paramount to limit adverse impacts of heat on urban inhabitants. While different adaptation measures are currently debated by the political authorities in Vietnam, decision-making is hampered by multiple scientific knowledge gaps and the lack of practical tools to support decision-making. This paper presents an approach to investigate the pattern and characteristics of the urban heat island in Can Tho City, located in Vietnam’s Mekong Delta. This study investigated the relationship between urban heat with urban structure types, building density and blue and green spaces. An urban structure type approach was used to classify and partition the city into spatial units of different types of buildings (housing archetypes, functions, infrastructure), degrees of planning (regular, irregular), densities and open spaces on the official block geometry of the official land use plan and linked to remotely sensed land surface temperatures. The results in the form of a series of risk analysis maps at a planning relevant scale, confirm the effects of land uses and urban structures on local temperatures and allow policy makers and planners to better understanding of the relationship between the urban temperatures, functions and densities in order to reduce the UHI and promote more sustainable and resilient urban development.
Developing Chorus Wave Model Using Van Allen Probe and Arase Data
Authors: Wang Dedong , Shprits Yuri , Feng Ting , Lepage Thea , Michaelis Ingo , Miyoshi Yoshizumi , Kasahara Yoshiya , Kumamoto Atsushi , Matsud Shoya , Matsuoka Ayako , Nakamura Satoko , Shinohara Iku , Tsuchiiya Fuminori
Published: February 2023

Chorus waves play an important role in the dynamic evolution of energetic electrons in the Earth’s radiation belts and ring current. Due to the orbit limitation of Van Allen Probes, our previous chorus wave model developed using Van Allen Probe data is limited to low latitude. In this study, we extend the chorus wave model to higher latitudes by combining measurements from the Van Allen Probes and Arase satellite. As a first step, we intercalibrate chorus wave measurements by comparing statistical features of chorus wave observations from Van Allen Probes and Arase missions. We first investigate the measurements in the same latitude range during the two years of overlap between the Van Allen Probe data and the Arase data. We find that the statistical intensity of chorus waves from Van Allen Probes is stronger than those from Arase observations. After the intercalibration, we combine the chorus wave measurements from the two satellite missions and develop an analytical chorus wave model which covers all magnetic local time and extends to higher latitudes. This chorus wave model will be further used in radiation belt and ring current simulations.
The multiple-scale hydrological processes observations at mountainous areas and its preliminary results
Authors: Tian Jie
Published: February 2023

High spatial heterogeneity, difficulty in monitoring and lack of soil hydrological processes have resulted in poor understanding of the key hydrological processes in topographically complex, high elevation mountainous areas, impeding the advancement and applications of mountainous hydrology and hydrological models. This research aims to understand the mechanism of key hydrological processes at multiple spatial scales (soil profile, hillslope, watershed, and region) in the Qilian Mountain ranges, Northwest China. To this end, an in-situ observation network has been set up to monitor the hydrological processes, including precipitation, infiltration, soil moisture, subsurface flow, evapotranspiration and runoff at the multiple spatial scales. The in-situ observations has been applied to: 1) quantify the soil moisture dynamics about infiltration, 2) gain a better understanding of the underlying hydrological mechanisms of preferential flow; and 3) understand the relationship between rainfall, soil moisture dynamics and evapotranspiration.
Outreach Films from the IAGA Social Media Working Group
Authors: Rogers Hannah , Pinheiro Katia , Sharan Shivangi , Leichter Barbara , Di Chiara Anita , Sanaka Sarasija
Published: February 2023

The International Association of Geomagnetism and Aeronomy (IAGA) is one of the associations under the International Union of Geodesy and Geophysics (IUGG) and acts as a non-governmental body to serve scientists and decision-makers in research establishments, government agencies, intergovernmental bodies, and private enterprises. IAGA promotes the work of Earth and space scientists studying the magnetic and electrical properties of the Earth, other planets, the Sun and their phenomena, and interplanetary bodies.Since December 2019, IAGA has had a dedicated social media group (under the Interdivisional Commission on Education and Outreach - ICEO) to promote the work of the organisation and encourage the building of an online community. IAGA social media platforms (including Twitter, Instagram, Facebook, LinkedIn, YouTube, and a blog) started as an alternative version of mailing lists but have expanded into creating original content. We aim to provide an easily accessible platform for news and an online community for IAGA members; to increase awareness of the varied work of IAGA, both within the community and to the general public; and to promote the work of early career researchers (ECRs) and under-represented groups in IAGA. In this talk we present the successes of our most recent undertaking, the filming of outreach materials. These have fallen into two main categories: 1) outreach films, and 2) filmed interviews with IAGA (and wider IUGG) members.Evidence of success in the first category include the “Magnetic Mosaic” film (directed by Katia Pinhero), which was a finalist film in the “Women in GeoScience” category and finished 5th in the Public Choice at the Earth Futures Film Festival out of 972 initial entries. In this film 10 female scientists take the viewer on a tour as they build a magnetic mosaic from the Earth’s core into the solar system. We have also won a grant to facilitate a children’s outreach project where puppet theatre is used for Bimbim the dog to learn the differences between planets in the solar system with his friends.Secondly, we have won an outreach Grant from the IUGG where we will produce a documentary and short movies containing interviews with researchers to connect a variety of subjects under the 8 IUGG associations. The documentary will be about the structure and science of IUGG while the short movies will contain interviews of Early Career Researchers. We wish to promote this ongoing work and direct listeners to how to access these materials for their own use.
Siberian Large Igneous Province: a combination of rift and platform magmatism during its formation
Authors: Krivolutskaya Nadezhda
Published: February 2023

The Siberian large igneous province (SLIP) is an enormous continental province in the world comprising the extra-large PGE-Cu-Ni deposits [1-3]. Its origin is under discussion for several decades including genesis of sulfide ores. Many models were suggested [4-6] where a plume activity and delamination of the crust are the main agents of its origin. Meanwhile, the link of deposits’ formation with these processes is unknown and still controversial. Almost all genetic constructions do not take into account the real geological structure of magmatic rocks within the province which reflects evolution of magmatism in space and time at the P-T boundary. The main feature of the province is an occurrence of rocks, fundamentally different in genesis. Two types of igneous rocks take part in the SLIP structure, i.e., platform (or traps per si) and rift basalts.  The first of them have sustained thickness, tholeiitic composition (6-7 wt.% MgO, 0.8 -1.6 wt.% TiO2, εNd = 0.14–1.90) and cover huge areas on ancient Siberian craton. The latter form small, rapidly pinching out flows of different composition in the Yenisey-Khatanga trough (YKT) and its feathering structures including the Norilsk-Igarka paleorift with PGE-Cu-Ni deposits.  The maximum compositional diversity characterizes the rift rocks varying from picrites to trachyandesites (3 -33 wt% MgO, 1.3-6 wt% TiO2, εNd = −11.0 - +6.6).  The fundamental difference between two types of magmatisms is crucial both for the SLIP formation and origin of the magmatic sulfide deposits. Primary it was suggested that rift magmatism preceded the trap magmatism but we proved that they operated synchronically within different tectonic elements during whole period of province formation. Magmatic activity began in the western part of the YKT from formation of subalkaline basalts of the Ivakinsky (Norilsk area) and Syradasaysky (South Taimyr) formations. They were overlapped by the Syverminsky, Gudchikhinsky (Norilsk) and Labaksky, Verkhnetamsky (Taimyr) formations. First platform basalts appeared in the Tunguska syneclise (Tuklonsky Formation) at the same time when rift basalts continued to erupt (Khakanchansky and Nadezhdinsy formations). The main impulse of the trap magmatism includes the Morongovsky, Mokulaevsky, Kharaelakhsky, Samoedsky,  formations in the Norilsk area, and Nidymsky, Kochechumsky formatiom in the Tunguska syneclise, and Betlingsky formation in Taimyr. Rift basalts synckonically exploded along the northern and southern boundaries of the YKT (Ayansky picrites, and Fadyukundinsky, Arydzhangsky, Maymechinsky formations) demonstrating its evolutions from the west to the east. It is supposed that this magmatic development and deposits’ formation realized due to a collision of the Kara and Siberian cratons at the Late Paleozoic – Early Mesozoic epochs.This study was supported  by RSF (project No 21-27-00387). 
A Tailored Fine Fuel Moisture Content Model for Improving Wildfire Danger Rating Systems
Authors: Perello Nicolò , Trucchia Andrea , D'Andrea Mirko , Meschi Giorgio , degli Esposti Silvia , Fiorucci Paolo
Published: February 2023

A change in wildfire regimes in several regions around the Earth has been acknowledged in recent decades, with an increase in the frequency of particularly severe events. Consequently, many wildfires management systems have been challenged, renewing interest in Forest Fire Danger Rating (FFDR) models to support preparedness and response phases. The Liguria Region (Italy) and the Italian Civil Protection supported independent research programs that led in 2003 to the development of the FFDR model RISICO. Nowadays the model is used as a decision-support tool by Italian civil protection systems at national and regional levels. RISICO model integrates weather conditions with vegetation types, topography, vegetation indices from satellite and ML-based wildfires susceptibility maps, in order to provide all information available. One of the main component of RISICO is the Fine Fuel Moisture Content (FFMC) model. Indeed, fine fuel moisture conditions influence the ignition and spread of wildfires, and particularly low FFMC values are often associated with the occurrence of severe events. A new formulation of the FFMC model has therefore been performed to increase its forecasting capabilities and the abilities to discriminate severe wildfire conditions. The FFMC model depends on vegetation types, differentiating the fine fuel moisture behavior through a different response time to weather conditions. This aspect makes it possible to consider the structural peculiarities of each vegetation type, differentiating then forest fire fire risk behavior. The model is also able to simulate fine fuel moisture content at different temporal resolution, ranging from hours to minutes. This makes it possible to describe in detail the fast dynamics of FFMC, which is of particular interest in environments characterized by a rapidly changing forest fire risk such as the Mediterranean environment. A reformulation and parameters calibration of the FFMC model has then been performed, to increase the reliability of the model. The use of the revised FFMC model to simulate moisture conditions in case of wildfires occurred in Italy in the last 15 years shows an increase in the model's ability to discriminate against severe events, characterized by particularly low fine fuel moisture values. 