bluuebunny/crossref_metadata_2025 huggingface dataset:
Combining terrestrial and marine electrical resistivity methods to improve data acquisition in the land-sea transition zone.
Authors: Tur-Piedra Jose , Ledo Juanjo , Queralt Pilar , Marcuello Alex , Diego-Feliu Marc , Alorda-Kleinglass Aaron , Rodellas Valentí , Folch Albert
Published: February 2023

In recent decades, there has been a growing interest in accurately characterizing the process of fresh groundwater discharge into the coastal ocean since it represents a significant pathway for solute from land to sea. Although SGD research has focused on quantifying water and solute fluxes, little is known about the physical forces, mechanisms, and distribution of SGD.Investigating interaction processes between the fresh and saltwater under the sea bottom represents a logistical and technical challenge. Traditionally, electrical geophysical methods have been solely used in the terrestrial part, and during the last decades, the method techniques have been introduced to marine environments. However, these methods are limited by their characteristics in obtaining subsurface resistivity data in the first few meters of the coast. Especially in the land-sea transition zone of microtidal environments, where many of the most critical processes take place, this data is traditionally not available. In this study, we developed a combination of methods to bridge the data gap between the terrestrial and marine realms. This study aims to characterize the FSGD in two aquifers from different geological contexts (alluvial and karstic) on the Mediterranean coast near Barcelona.To study the transition zone of the aquifer with a good spatial resolution, the amphibious electrical tomography method has been chosen, combining a terrestrial and aquatic line fixed in contact with the marine sediment. Profiles perpendicular to the coastline has been made in a shallow water area to obtain electrical resistivity data of the seabed at a local scale. The configuration used is Dipole-Dipole and Wenner-Schlumberger, with an investigation depth of 10 m. Based on the results, designing a 3D model of electrical resistivity in marine sediments was possible. In parallel to getting electrical resistivity data, manual piezometers were used to bring porewater samples at different points.We have been able to measure the presence of freshwater or brine, and we have identified differences in the geometry depending on the geological context, where the karst environment is the one that presents a more significant proportion of freshwater saturating the marine sediments. Therefore, amphibious electrical tomography is a non-invasive method that detects resistive zones of marine sediments associated with discharge processes and can be instrumental in characterizing the presence and distribution of SGD. AcknowledgmentsThis work was partly funded by the Spanish Government (grant no. PID2019-110212RB-C22) and the project TerraMar (grant no. ACA210/18/00007) of the Catalan Water Agency.
Ocean mapping: Finding and compiling spatial data on extreme environments – key information even for a general mapping project such as EMODnet geology
Authors: Asch Kristine , Müller Alexander Müller , Blischke Anett
Published: February 2023

Data and information on the ocean floor is hardly findable scattered, rarely compatible, often inaccessible, and often usable only by insiders. The main reason for this situation is the inaccessibility of the ocean floor and the need to use and rely on mostly geophysical methods in order to create a geological map. Therefore, the ocean floor is by far not as thoroughly explored as on-shore areas: “we have better maps of the surface of Mars and the Moon than we do of the bottom of the ocean.” [Gene Feldmann, NASA, 2009: https://www.nasa.gov/audience/forstudents/5-8/features/oceans-the-great-unknown-58.html].Thus, in 2009 the European Commission established the European Marine Observation and Data Network (EMODnet) programme, subdivided into seven thematic projects, one of which is EMODnet Geology. It aims to build digitally available map layers of the European Seas to be interoperable and generally and freely available. Within the EMODnet Geology the workpackage “Seafloor geology” (lead by BGR) compiles and harmonizes marine geological and geomorphological data from the EMODnet partners all over Europe and adjacent areas, to be made available on the EMODnet Geology portal [https://emodnet.ec.europa.eu/en/geology] and the BGR portal [https://geoportal.bgr.de].These data contain information on geomorphology, age, lithology and genesis (process, environment) of each unit and encompass two relevant aspects of extreme environmental mapping:a) they are often mapped in extreme environments such as mid-oceanic ridges, rift propagation zone, and subsea volcanic centres, e.g. the Grimsey lineament rift propagation zone located north-of Iceland; b) they contain information on past extreme environments, e.g. subglacial, volcanic or deep sea environments.Underpinned by examples, this poster will present and discuss both aspects and outline the benefits of mapping in extreme environments also for general mapping projects such as EMODnet geology.
VLF banded structured events observed in the 5–39 kHz frequency range in Finland
Authors: Macotela Liliana , Manninen Jyrki , Fullekrug Martin
Published: February 2023

Analysis of very low frequency (VLF) radio waves provides us the remarkable possibility of investigating the response of both the lower ionosphere and magnetosphere to a diversity of transient and long-term physical phenomena originating on Earth (e.g., atmospheric waves) or in space (e.g., CMEs). In this work, broadband VLF data measured at Kannuslehto, in northern Finland, is used to characterize a new type of VLF emissions displaying a strip-like structure observed in the 5–39 kHz frequency range. Analyzing campaigns from 2006 to 2022, we found that this emission can be observed either in the high VLF frequency ranges or spanning from low to high frequency ranges. We also found that the events last usually less than 1 hour, occur during evening hours, and during quiet geomagnetic conditions. We discuss the seasonal dependence of this kind of events by analyzing a complete year during 2022. We also discuss whether their origin might be due to plasma instabilities in the magnetosphere, as in the case of auroral hiss.
Understanding the Abundance, Variability and Sources of Ice NucleatingParticles (INPs) over the Kara and Laptev Seas in the Eurasian Arctic
Authors: Li Guangyu , Welti André , Rocchi Arianna , Pérez German , Thurnherr Iris , Dall’Osto Manuel , A. Kanji Zamin
Published: February 2023

The Arctic region is sensitive to climate change, experiencing accelerated warming. Cloud radiative properties and related feedback mechanisms on Arctic climate are highly uncertain and dependent on the cloud phase. Primary ice formation in Arctic mixed-phase clouds is initiated by INPs. So far, little is known regarding the abundance, variability, and potential sources of INPs in the Arctic owing to the scarcity of data, particularly in the marine environment. We study the INP-cloud interactions to improve the understanding of the abundance and sources of INPs in this region.  We present results from a cruise-based Arctic Century Expedition, which took place from 5 August to 6 September 2021 in the previously uncharted Kara and Laptev Sea in the Eurasian Arctic. Ship-borne INP concentrations (immersion mode) and their spatiotemporal variabilities will be presented and linked to the physicochemical properties of ambient aerosols, including particle size distribution, heat lability, chemical compositions, and biological activities. Additionally, geographical variability of INPs along the ship track are investigated to assess the influence from different origins, e.g., sea ice, marine or terrestrial origins. Ultimately, we will report the results from the in-situ aerosol generator experiments to reveal the phase partitioning of INPs at the sea-air interface highlighting the importance of the aerosolization mechanisms to the production of marine INPs.
Decision-making irrigation system based on MIKE SHE model for addressing water scarcity in Mediterranean olive orchards
Authors: Kourgialas Nektarios , Morianou Giasemi , Tzerakis Konstantinos , Malandraki Afroditi , Psarras Georgios
Published: February 2023

In the Mediterranean area, Greece is considered as one of the most important olive producing countries. Specifically, olive (Olea europaea) is the main crop covering more than 75% of the total tree cultivation area, while about 45% of the total cultivated area is being irrigated. Groundwater is the main source of irrigated water in Greece, but the growing demand and the climate change are putting this resource in risk.  The design of an optimal irrigation plan, based on detailed measurements and modeling tools, can effectively contribute towards water saving with no loss on crop yield, in the area. In this study, an IoT-based decision-making system for the management of irrigation water resources of olive orchards in a small sub-basin of Lasithi, Crete, Greece is presented.  The system integrates monitoring of soil moisture and atmospheric parameters in four fields within the study area and modeling approaches, using the modules of MIKE-SHE model, to simulate water flow in the unsaturated zone at the sub-basin level.  Additionally, 45 soil samples (from 3 different soil depths) have been collected and analyzed from the study area for soil texture, bulk density, rock percentage, pH, organic matter, and mineral nutrients. After the successful calibration of the model (comparison of simulated against observed soil moisture values) the spatio-temporal representation of soil moisture is used as guidance for developing optimal irrigation scheduling, considering olive tree water requirements, for the entire study area (sub-basin), even for olive orchards with lack of monitoring equipment installation.ACKNOWLEDGEMENTSThe authors acknowledge contribution of the AgriCapture CO2 - Horizon 2020 project. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 101004282
Magnetospheric Auroral Asymmetry eXplorer: observing the aurora to uncover how energy flows in space
Authors: Liemohn Michael , Ridley Aaron , Welling Daniel , Halford Alexa , Immel Thomas , Connor Hyunju , DeJong Anna , Fasel Gerard , Gabrielse Christine , Garcia-Sage Katherine , Harding Brian , MacDonald Elizabeth , Matsuo Tomoko , Spanswick Emma , Zou Shasha
Published: February 2023

The Magnetospheric Auroral Asymmetry Explorer (MAAX) mission makes a major leap forward in determining how magnetosphereionosphere electrodynamic coupling regulates multi-scale auroral energy flow through the near-Earth space environment. Recently proposed to NASA’s Heliophysics Small Explorer program, MAAX accomplishes this by: (1) Understanding how seasons and tilt of the magnetic field regulate energy flow from the solar wind through the system; (2) discovering how the formation, evolution, and interhemispheric asymmetries of nightside meso-scale auroral features are regulated by the auroral background conductance; (3) determining how the time-dependent magnetospheric energy flow controls multi-scale auroral dynamics. The solar wind energy enters the magnetosphere mainly through dayside reconnection and is stored in the magnetosphere, which later converts to plasma and neutral thermal and kinetic energies. Dynamic smaller-scale processes in the nightside magnetosphere map from the magnetosphere to the ionosphere, resulting in auroral structures that have fascinated people for millennia. Observations of the aurora have been used as a window to probe and understand these dynamics even beyond the Earth system. The magnetic field lines in which the aurora occurs thread through both hemispheres. Traditionally, auroral observations from one hemisphere are assumed to be conjugate, while recent observations suggest this may not always be applicable. With auroral observations from one hemisphere, we can only understand some of the processes that control the flow of energy through the system. However, with observations in both with observations in both hemispheres we gain a deeper understanding into the dynamics of this integrated system. MAAX comprises two observatories in circular polar orbits at 20,850 km altitude for viewing of the auroral ovals in both hemispheres. Each observatory carries a single high-heritage UV imager to close the science objectives that operate poleward of +/-35° latitude. For the first year of the mission, the observatories are spaced at 90° to allow continuous coverage on one oval, then the other with a 6-hour duty cycle. This phase also allows for intervals in which both view the same hemisphere or both view the same longitude but different hemispheres. For the second year of the mission, the observatories are spaced at 180° to have simultaneous complete viewing of both the northern and southern auroral ovals with a 4.5 hr/1.5 hr on/off duty cycle. Discussed here is the science motivation of the mission concept and the numerical modeling trade studies to optimize the mission characteristics to achieve the proposed objectives.
Managing climatic risk in cocoa by designing resilient agroforestry systems based on a functional trait approach
Authors: Abdulai Issaka , Hoffman Munir , Dippold Michaela , Asare Richard , Rötter Reimund
Published: February 2023

Climate change projections indicate that significant areas of the current cocoa cultivation areas in West Africa are likely to experience unfavorable climatic conditions by 2050. Water use efficient agroforestry systems are considered to be an important option to adapt cocoa to climate change. Water use efficiency and complementary soil water use between cocoa and shade trees have been reported in previous studies in Indonesia but in our previous study in Ghana, popular native shade tree species Albizia ferruginea and Antiaris toxicaria were found to have a strong competitive water use advantage over cocoa plants during an extreme drought experienced during 2015/16. Cocoa plants under no shade were relatively more resilient with higher survival rate and post drought recovery.While past research studies   were each limited to few selected shade tree species being investigated despite the huge numbers within cocoa landscapes. To overcome this limitation, an approach based on functional traits of trees in terms of water use is proposed to understand their effect on water use efficiency and drought resilience in cocoa agroforestry systems rather than describing individual species. We apply this concept across temporal and spatial scales in a marginally suitable cocoa climate in Ghana. Shade tree species have been categorized into phenological trait groups (evergreen, deciduous, or brevi-deciduous) under which detailed above- and belowground traits interactions with cocoa plant and effect on water use has been evaluated.The following hypotheses are being tested: (i) shade trees in the three phenological trait groups exhibit significant difference in their root and water uptake depth, and, thus, affect environmental conditions relevant for cocoa, (ii) cocoa plant above- and belowground morphological and physiological traits are influenced by shade tree phenological and morphological traits and their modification by micro-climatic (light, temperature, relative humidity and VPD), and soil (water and nutrients) conditions over different seasons.Replicated plots of 19 shade tree species distributed across the three phenological trait groups have been established for analysis of functional traits interactions in such a multi-species agroforestry system. We determine root specific traits through direct sampling, stable isotope analysis for assessment of water use portioning between the various shade tree groups and cocoa plants. Soil moisture, temperature and relative humidity and light sensors were installed in each plot. Cocoa plants under different micro-climatic impact zones of the shade trees have been monitored for a full production cycle.  The shade trees impact on the cocoa plant productivity (morphology and yield traits) has been evaluated. Complementary and non-complementary shade tree species with respect to their trait interactions and effect on cocoa plant productivity have been identified.
Development of a national-scale VIC hydrological model to project future changes of the water resources of the Philippines
Authors: Scheidegger Johanna , Jackson Christopher , Barkwith Andrew , Wang Lei , Guzman Maria Aileen
Published: February 2023

We applied a version of the macro-scale hydrological model VIC, into which we incorporated a 2D lateral groundwater flow model, to simulate the hydrology of the Philippines. We used global data sets to parameterise the model, which uses a ~1km grid to represent each of the country’s islands; global meteorological driving data were downscaled to this resolution. The model was calibrated over the historical period (1990-2019) against available observed river flow time-series by adjusting soil, aquifer, and riverbed hydraulic properties; Nash-Sutcliffe Efficiency scores of up to 0.53 were obtained. We applied projections of future climate for the 2050s and 2070s derived from global climate simulations undertaken by the UK Meteorological Office’s Hadley Centre – the UKCP18 projections – considering two greenhouse gas concentration pathways: RCP2.6 and RCP8.5. Projected future reductions in precipitation translate into decreases in surface runoff, groundwater recharge, and river baseflow, on average, but the simulations highlight regional differences in groundwater and surface water availability over both the historical and future periods.
Climate-related changes in total alkalinity as a key to understanding ocean acidification in the coastal zone
Authors: Kulinski Karol , Aguado Gonzalo Fernando , Bromboszcz Laura , Diak Magdalena , Koziorowska-Makuch Katarzyna , Makuch Przemyslaw , Palka Izabela , Prusinski Piotr , Saghravani Seyed Reza , Szymczycha Beata , Winogradow Aleksandra
Published: February 2023

Rising CO2 concentrations in the atmosphere have a multidimensional influence on marine ecosystems. Through amplifying the greenhouse effect they lead to seawater temperature increase, which initiates cascade changes in the environment. In addition to this climatic pathway, increasing atmospheric CO2 concentrations cause also an overall increase of CO2 concentrations in surface seawater and, consequently, a pH decrease – a mechanism called Ocean Acidification (OA). OA is already fairly well understood and traceable in the open ocean waters, where large-scale projects and actions supply an enormous amount of observations and experimental data and where the magnitude of OA is to a large extent thermodynamically consistent with the increase in atmospheric pCO2. In the coastal and shelf seas, OA is still a considerably understudied phenomenon despite their high socio-economic importance and potentially great vulnerability of these regions to acidification due to often lower salinity and corresponding lower buffer capacity of waters as compared to open ocean.In the present study, we underline the importance of total alkalinity (TA) as the key factor shaping the OA dynamics and pH fields in the coastal and shelf seas. The extensive research performed in 2018-2022 extended from the brackish Baltic Sea through the open waters of the eastern Fram Strait to the Spitsbergen fjords affected by the high inflow of meltwaters. It revealed extremely high variability in the marine CO2 system structure and significantly different influences of freshwater input in the investigated regions. The observed overall spatial and temporal (seasonal) variability in TA extended in the broad range between <350 and 4,320 µmol kg-1. This makes TA a fundamental variable for studying the large-scale pH and pCO2 changes and forecasting the development of OA in the coastal zone in the future high-CO2 world. This large-scale study can be considered as the reference for future OA research in the investigated regions and simultaneously calls for action to include TA in the routinely observed parameters in the coastal waters.
Assessing plant water status in Merlot vineyards using Worldview-3 multispectral images in central Spain
Authors: Nowack Juan Claudio , Atencia Luz Karime , Gómez del Campo María , Tarquis Ana María
Published: February 2023

Water status in vineyards is a determining factor, given its relationship with productive and physiological parameters such as vegetative growth, berry ripening, yield and overall wine quality. In-field measurements, through a pressure chamber, provide very accurate and reliable measurements of midday stem water potential (Ψstem), a direct method for determining a plant’s water status by quantifying the tension with which water is retained in the leaf. Despite the robustness of this method, it is not practically applied to extensive commercial vineyards as it is a labour-intensive practice which can narrowly evaluate the significant intra-field variability. Remote sensing offers large-scale information at a single point in time without the need to be physically present in the field. This study aims to assess the use of multispectral imagery from Worldview-3, a commercial satellite, as a tool to indirectly estimate water status in the vineyard through different Vegetation Indexes (VI).This research was carried out in a commercial Merlot vineyard in Yepes (Toledo), an arid area in central Spain where rainfall and irrigation water availability is scarce. The vines were established in 2002 and arranged on a trellis with a plantation spacing of 2.6 x 1.1 m. Five different irrigation doses were tested to obtain variability in vine water status. Drip irrigation emitters were identical in all treatments ( 2 l h-1), but distances between emitters were adjusted to modify irrigation levels. Treatments were designed as follows: T1 (100% dose) emitters every 0.25 m, T2 (50%) emitters every 0.5 m, T3 (25%) emitters every 1.0 m, T4 (0%) no emitters and T5 (25%) underground emitters every 1.0 m. The results will be discussed in the context of deficit irrigation.
Hubble and Juno observations of Jupiter’s auroras and magnetospheric dynamics during the Juno Extended Mission
Authors: Nichols Jonathan D. , Clarke John , Grodent Denis , Bonfond Bertrand , Cowley Stanley , Gladstone Randy , Bagenal Fran , Orton Glenn , Lysak Bob , Allegrini Frederic , Connerney Jack , Mauk Barry , Clark George , Wilson Rob , Ebert Rob
Published: February 2023

We present simultaneous Juno and Hubble Space Telescope of Jupiter's far-ultraviolet auroras obtained as part of a programme of observations covering 3 years of Juno's Extended Mission.  We show that bright, expanded dusk-side southern main emission is associated with large-scale convection dynamics, dusk-side main emission arcs are associated with field-aligned currents, and equatorward diffuse emission and patches are associated with plasma injections in the middle magnetosphere occurring within intervals of enhanced plasma density, ongoing interchange motion and magnetospheric convection.  These results shed light on the relation between the main auroral emission and magnetosphere-ionosphere coupling currents, and radial force balance in the magnetosphere. We also report on unusually bright and expanded southern auroral emissions observed during PJ 43.
Sequential multiple-point statistics simulations conditioned on arithmetic averages
Authors: Levy Shiran , Friedli Lea , Mariéthoz Grégoire , Linde Niklas
Published: February 2023

We seek to develop a methodology enabling fast geostatistical simulations honoring both geophysical data and a complex prior model. Particularly, we consider a multiple-point statistics (MPS) framework in which a training image (TI) describes the available prior knowledge. Accurate posterior sampling is then possible by using a so-called extended Metropolis algorithm in which proposals are drawn from the prior using sequential geostatistical resampling. Such a Markov chain Monte Carlo (MCMC) algorithm will eventually locate and sample proportionally to the posterior distribution, however, it is often exceedingly slow and typically demands millions of MCMC iterations before the posterior is sampled sufficiently. We are developing a methodology in which the MPS simulation is built up iteratively pixel-by-pixel starting from an empty grid. At each pixel, multiple proposals are generated using an MPS algorithm and the proposals are accepted proportionally to the likelihood considering conditioning data in terms of linear averages (for instance geophysical data). The likelihood function is generally intractable as it depends on the pixels that have not yet been sampled. We approximate the likelihood function using a Gaussian model in which the posterior mean and covariance are updated sequentially as the simulation builds up. The posterior statistics are approximated by running the algorithm multiple times (sequentially or in parallel). Considering crosshole first-arrival ground-penetrating radar data, we assess the accuracy of our methodology both for multi-Gaussian priors for which analytical posteriors are available and for more complex training images against the extended Metropolis method. Our approach is inherently approximate due to the use of a finite training image, a finite number of candidates for each pixel and the need to approximate intractable likelihood functions. Nevertheless, preliminary results are promising as this method allows directly obtaining a reasonable estimation at a reduced computational cost compared to MCMC.
A new EDI Division of the Italian Geological Society
Authors: Amadori Chiara , of the Italian Geological Society EDI Division
Published: February 2023

The study by Agnini et al. (2020) has described the scenario over the last two decades about the presence of women working in geosciences in the Italian University system. Data show a slightly positive trend in the female percentages of both full (from 9.0% to 18.5%) and associate professors (23.6% to 28.9%). Conversely, the same positive trend is not seen among research fellows/assistant professors, although the PhD population (i.e., the career starting point) shows near gender balance. The under representation of women among permanent researchers is around 35% and 32% for non-permanent researchers. In Italy, the Glass Ceiling Index is alarmingly high, 3.02, and never approached the value of 1 that indicates no difference between women and men in terms of their chances of being promoted. It is clear that more efforts are needed to promote work-life balance policies and a firm discouragement of the prevailing patriarchal mentality would eventually help in reconciling family and work to give equal opportunities to men and women.On this topic, in 2021, the Italian Geological Society (SGI) created a new Division dedicated to Equity, Diversity and Inclusion, “PanGEA, Geoscienze Senza Frontiere”. This new SGI Division aims to coordinate and promote activities to overcome differences in gender, sexual orientation, ethnic origin, disability, language and age and support inclusiveness in Italian geology. The Division is also conceived as an open environment, intended to create opportunities for communication, mutual support and professional development. To do so, the Division organizes – at least once a year – a national workshop to connect academic geoscientists to professionals from the public and private sectors and teachers. We believe in the need to build supporting and mentoring actions at different levels because geology is a discipline that must evolve to embrace all kinds of diversity.  Agnini, C., Pamato, M. G., Salviulo, G., Barchi, K. A., and Nestola, F.: Women in geosciences within the Italian University system in the last 20 years, Adv. Geosci., 53, 155–167, https://doi.org/10.5194/adgeo-53-155-2020, 2020.
Fractal Dimension of nonattracting chaotic sets
Authors: Roemer Raphael , Ashwin Peter
Published: February 2023

The fractal dimension of a nonattracting chaotic set provides information about its geometric complexity and can often be of practical use. For example in the case of a chaotic saddle on a (fractal) basin boundary between two basins of attraction where the boundary is the stable set of the chaotic saddle. Then, the fractal dimension of the saddle and of the boundary provide information about the impact of small changes to the initial conditions on the future behaviour of the system, when the system is in a state close to the boundary.This information is highly relevant in the context of climate tipping phenomena.Building on Edward Ott’s and David Sweet’s work from 2000, we will discuss how to rigorously construct a measure on a chaotic repellor which leads to the estimation of its fractal dimension. Further, we discuss the fractal dimension of its stable and unstable set.
Geotopes as a tool for geoscience teaching and outreach
Authors: Friedrich Anke M
Published: February 2023

Traditional geological field education includes organized trips of large student groups to geological outcrops. Typically, instructors guide students to outcrops and give (mini-) lectures. The students’ notes consist of the provided verbal summaries instead of one’s sketches and descriptions of outcrops, often leading to poor reports. In 2020, the Covid-19 pandemic prevented group travel to geological sites, which halted such forms of teaching. To continue field education despite the contact restrictions, I designed an alternative way of field-based learning through proactive engagement of students in trip planning, site selection, outcrop study, discussion, and report writing. The concept involves (1) geotope sites provided by survey offices (e.g., Geotoprecherche LfU Bayern) because they contain precise outcrop locations and just the right amount of relevant geological information allowing students to visit geotopes of their interest on their own. It also involves (2) a shared project on GOOGLE EARTH WEB to which students post field photos, sketches, and text, which they present in (3) in the weekly zoom-seminars (geotope seminar). Instructors provide feedback and stimulate discussion among participants based on the presented field observations. The resulting sketches and reports are of higher quality because they are exclusively based on the student’s concentrated work at the outcrop (only 2 per day). However, no instructor accompanied any student in the field. The geotope seminar accommodates day trips, multi-day field exercises, and mapping projects for geoscience students of all ages and interests. Geotope courses could be offered to the broader public if safe site access is secured.
Drivers of the sudden Antarctic sea-ice decline events
Authors: Goyal Rishav , Sen Gupta Alex , England Matthew , Jucker Martin
Published: February 2023

Antarctic sea-ice extent showed an unprecedented decline during 2015/16 after showing a weak positive trend since the last four decades. Many studies have attempted to understand the reasons behind this sudden decline in the sea-ice and have shown important influences from the atmosphere as well as the upper ocean processes. In this study, we attempt to understand similar sudden Antarctic sea-ice decline episodes in the long pre-industrial control simulations of multiple CMIP models. We examine the change in sea-ice extent from September to January and classify the events as sudden decline events based on the magnitude of this change. Composite analyses are then carried out to understand the similar atmospheric as well as oceanic processes as play during such events. Preliminary analyses suggest an important role of the Zonal wave 3 amplification during September – November period similar to what was observed during 2016. We also notice a clear El-Nino signature in the tropical Pacific from the preceding austral summer with a presence of warm SSTs around Antarctica during the sea-ice growth season. More detailed analysis are currently being carried out and the results will be presented during the conference.
The 2021-22 unrest of La Fossa volcano (Vulcano Island, Aeolian Archipelago) by the side of fumarole chemistry: clues on the magmatic source in the precursory and ongoing phases
Authors: Paonita Antonio , Federico Cinzia , Bellomo Sergio , Di Martino Roberto Maria Rosario , Gattuso Alessandro , La Pica Leonardo , Pecoraino Giovannella , Pisciotta Antonino Fabio , Sortino Francesco
Published: February 2023

In September 2021, the La Fossa volcano entered a new phase of unrest. The monitoring system, operating in the island since late ‘80s, recorded a sudden variation in seismicity, ground deformation, fumarole temperatures, soil and plume degassing. These variations were interpreted as due to the fast vaporization and expansion of the hydrothermal system (Federico et al., submitted), hypothesized at depth > 1.5 km bsl. At the same time, fumarole chemistry showed clear-cut variations, related to the dominant contribution of the magmatic gas over the hydrothermal one. The CO2 content and the helium isotope composition of the magmatic source revealed the appearance of a more primitive magma, compared to that feeding the fumaroles in the previous period, during the climax of the unrest. The signs of the enhanced contribution of magmatic gases in the fumarolic gases was already evident since 2018, so the 2021 unrest appears to have been the outcome of a long lasting preparatory phase. The systematics of gas species together with C and He isotopes, emitted from fumaroles after the first months of the unrest, revealed the appearance of a different magmatic component, poorer in N2, 3He and richer in He, S and 13C. The magmatic contribution is persistently overwhelming the hydrothermal one by the time of this communication.
Application of Rain-on-Grid for flash flood modeling: A case study in the Selška Sora watershed in Slovenia
Authors: Alexopoulos Marcos Julien , Iliopoulou Theano , Dimitriadis Panayiotis , Bezak Nejc , Kobold Mira , Koutsoyiannis Dimitris
Published: February 2023

Rain-on-Grid (RoG) modelling offers an attractive alternative to more traditional routing methods. Currently, few publications are addressing the suitability of this approach to modelling a storm event, and fewer benchmark findings present its possible limitations. In the present study, it is verified whether RoG is able to replicate the 2007 flash flood event that occurred in the Selška Sora watershed, located in western Slovenia. The results are validated against a high-resolution benchmark run, and the flood footprint extracted from the field by the Slovenian Environment Agency. Results display a satisfactory description of the flood event using uniform station rainfall data as an input. The flood extent slightly exceeds the confines of the runup measured in the field. RoG offers a more realistic description of the downstream hydrograph, with a sharper initial peak, when antecedent soil moisture is lower.
 
Keywords: Rain-on-Grid, Flash flood, Slovenia
Reconstructing the surface temperature fields of the mid-Pliocene Warm Period using climate models and a variety of climate proxy data sets.
Authors: Hargreaves Julia , Annan James , Mauritsen Thorsten , McClymont Erin
Published: February 2023

We discuss the construction of a global climatological reconstruction of the mid-Pliocene Warm Period, which is the focus of the current PlioMIP (around 3.2 Ma BP). Our method uses an ensemble Kalman smoother to blend fields of model output, generated here by two generations of the PlioMIP project, with sparse proxy-based estimates of temperature. The methodology was previously presented by Annan et al 2022 in application to the Last Glacial Maximum. In this presentation we contrast results obtained from two different data compilations. Firstly we use the PRISM proxy estimates for sea surface temperature from an interval 15ka either side of MIS KM5c (Foley and Dowsett 2019, Haywood et al 2020), that is 3.205+-0.015Ma. This contains 34 data points on the 5x5 degree grid that we use for our analysis. We contrast this with analyses performed in the PlioVAR project (McClymont et al 2019) covering a slightly narrower interval of 3.205+-0.01Ma. These analyses are based on a different age model and multiple calibrations of UK37 and Mg/Ca. The full data set contains 31 gridded data points.Using the PRISM data, our estimate of the global temperature anomaly is considerably warmer than most previous estimates, suggesting a significant discrepancy between the models and the data. Further calculations suggest that the PlioVAR data show more consistency with the models, but uncertainty remains high. We discuss the implications of this for the creation of reliable climate reconstructions.
Making water models more inclusive and interdisciplinary to underpin sustainable development
Authors: Mustafa Syed M. T. , Ala-Aho Pertti , Marttila Hannu , Huysmans Marijke , Comte Jean-Christophe , Shamsudduha Mohammad , Ghysels Gert , Schilling Oliver S. , Hoffmann Richard , Rossi Pekka M. , Avellan Tamara , Haghighi Ali Torabi , Peeters Luk , Pulido-Velazquez Manuel , Larocque Marie , Loon Anne Van , Ferré Ty Paul Andrew , Brunner Philip , Hendricks-Franssen Harrie-Jan , Klöve Björn ,   Syed M T Mustafa
Published: February 2023

Reliable predictions of water systems’ response to external pressures and ongoing changes are highly important to ensure informed decision-making to support sustainable water resources management for human use and the functioning of healthy ecosystems. Recent strong development of numerical models offers a potential to understand and forecast water systems under anthropogenic and climatic influences to provide information for decision-making, process understanding of the ‘unseen’ part of the water cycle and hazard risk analysis. However, the reliability of numerical model predictions is strongly influenced by various sources of uncertainties, data qualities and assumptions, and often lacks stakeholders' point-of-view. A new, improved approach is needed and in this paper, we present six basic principles to improve the reliability and accuracy of numerical water model predictions considering explicitly stakeholders' needs and, thereby, better serving the society. Six highlighted principles are: (i) clearly defining the objectives and the purpose of the model, sustaining them during the entire modelling process; (ii) incorporating expert and local community knowledge through stakeholders' feedback; (iii) implementing a multi-model approach in which a range of conceptualizations are explored ; (iv) considering and representing the uncertainties arising from model inputs, parameters, conceptual model structure and measurement/information error; (v) translating the results to concrete and understandable strategies that policymakers can use for their informed decision-making; and (vi) long term capacity building and monitoring data collection to reduce knowledge gaps, test and improve predictions. We argue that implementing these six principles reduces uncertainties, improves the predictive capacity of the numerical water models, and ensures informed decision-making to support sustainable water resources management and thereby serve society better.
IUGS Heritage Stone Designation – First Experiences
Authors: Ehling Angela
Published: February 2023

Natural building stones are almost everywhere related to the cultural heritage of societies. Making the public aware of their importance and diversity is the main objective of the IUGS Heritage Stones Subcommission.One way of doing this is to designate significant natural stones as an „IUGS Heritage Stone“. According to definition it is a natural stone that has been used in significant architecture and monuments, recognized as integral aspects of human culture.Since 2016, 32 natural stones from several parts of the world have been designated by the IUGS. It is a good time to look at what experiences we have had both in the designation process and with the impact of designations. Is the process simple, transparent and still on a strictly scientific basis? What outreach do we have, geographically, professionally, publicly? What is good and what can we improve?The designation process has been changed last year and it is planned to streamline it regarding the process (not substantive) a bit for the next time. The provenance of the 150 corresponding and voting members as well as the designated stones shows a geographical disbalance. 23 designated Heritage Stones are from Europe, 5 from Amerika and 4 from Asia.In the presentation, further facts are evaluated, e.g.: Which persons / institutions are behind the applications? What effects did the designation of the stones have? The answers are result of a survey and will be the basis for the further optimisation of the work of the IUGS heritage Stones Subcommission.
The role of rivers and lakes in damping flow variability introduced by hydropower
Authors: Elenius Maria , Lindström Göran
Published: February 2023

Hydropower regulations may significantly increase the variability of flow at especially short time scales when compared with the natural hydrological regime to which river ecosystems have evolved over long time periods. This can be detrimental for river habitats and for many organisms. Attenuation of the variability in rivers and lakes improves ecological status at some distance downstream of the introduced variability. Being able to accurately estimate this distance is critical for the evaluation of ecological status. The attenuation of introduced flow variability has only been studied previously for specific rivers and lakes, and the dominant mechanisms have not been analyzed in detail. In this work, the attenuation rate and its important drivers is studied for lakes and regulated rivers in all of Sweden by comparing the results of hydrological and hydrodynamic models with observations. We performed Fourier transformation of flow time series obtained with a) the Hydrological Predictions for the Environment (HYPE) model, b) an extracted model representing only river processes, c) the diffusion wave equation, and d) from observed flow at several hundred stations. The reduction of the amplitudes along rivers and in lakes was then analysed. This damping in rivers and lakes was further compared.In many regulated rivers in Sweden, flow variability of periodicity 7 days is dominant among periods varying from a couple of days up to one month. The analysis further shows that variability with periodicity days to months typically attenuate with an exponential rate that is largest for short periods. Attenuation of these periods in rivers is mainly driven by processes within rivers, as opposed to catchment features such as the distribution of rain or soil properties. Further, rivers in regulated systems often resemble cascades with long stretches of rivers with low gradients in elevation between the dams. The associated attenuation in these “lake-alike” rivers can be well described by hydrological simulations with HYPE using a simple linear attenuation box. In contrast, the sometimes-used diffusion wave equation is often unable to replicate the observed attenuation here. Lakes have larger attenuation potential than rivers, especially at low flows.Our work supports the assessment of ecological status and management decisions by improving the estimates of distances required for attenuation, and provides important insights on attenuation processes.Elenius, M.T. and G. Lindström (2022) Introduced flow variability and its propagation downstream of hydropower stations in Sweden. Hydrology Research 53(11), 1321-1339. doi: 10.2166/nh.2022.138
Influence of organic amendments, moisture content and temperature on carbon mineralization of forest soils
Authors: Krahl Ina , Kalbitz Karsten , Siewert Christian
Published: February 2023

Predicting soil organic carbon (SOC) mineralization under changing climatic conditions is complicated by the diversity of SOC composition. We combined incubation experiments with continuous respiration measurements and thermal analysis to investigate the informativeness of SOC thermal stability. Thermogravimetry is used in studies to determine soil properties such as total organic C, nitrogen, and clay content and to investigate the relationships between thermally labile and stable SOC and biodegradability. Soil respiration (SR) was measured in forest soils with added organic materials (wood, litter, and weeds with C contents of 49, 10, and 35%, respectively, and N contents of 0.1, 0.6, and 3%, respectively) at 20°C and 10°C and different soil moisture contents (5, 10, 20, 40, and 75% of field capacity). Wood amendments were further subdivided into pine (Pinus sylvestris) and beech (Fagus sylvatica) with three different particle sizes. We used topsoil samples from a pine forest, a beech forest, and a long-term agricultural experiment with different properties (C in %: 1.5, 2, and 4; clay in %: 5, 9, and 25, respectively). Basal respiration increased with soil C content, while Q10 levels decreased with field capacity 10 > 40 > 75% in forest and agricultural soils. This order changed depending on the sampling location when organic material was added. Decreasing wood particle size significantly increased SR. Weed additions caused the highest increase in soil respiration. After 10 weeks of incubation at different moisture and temperature conditions, organic amendments were mineralized faster in beech forest soils than in soils under pine forests. A multifactorial analysis of variance showed a significant influence (p < 0.01) of the interactions between temperature, moisture, site, and wood particle size on SR. Preliminary results from analysis of changes in thermal mass loss (TML) between 200 and 550 °C (reflecting SOC thermal stability) due to added organic material and incubation will be presented. Approaches to determine relationships between TML and carbon mineralization will be discussed.
Lagrangian flow networks for passive dispersal: tracers versus finite-size particles
Authors: Valente Deoclécio , Guseva Ksenia , Feudel Ulrike
Published: February 2023

Passive dispersal of different materials in ocean flows has gotten considerable attention over the last decade to increase our knowledge about the distribution of seeds plants among islands and coastal areas, the transport of larvae of different organisms between habitats and the transport of litter. Most studies have treated these objects as tracers to investigate distribution patterns and connectivity between different areas. We compare this approach with a study that considers the objects' size and density and discusses the deviation from the tracer approach. To this end, we introduce a two-dimensional kinematic velocity field which allows us to study the connectivity between an arbitrary number of islands located at arbitrary but prescribed positions in an open flow of a given direction. First, the mixing induced by the islands, which act as obstacles in the flow, was accounted for with the inclusion of a von K\'arm\'an vortex street in the wake of each island. Furthermore, we accounted for the size and density of particles approximated as spheres. Finally, we treated the particles as inertial particles experiencing various forces in the flow and computed their trajectories in a given flow field by solving the Maxey-Riley equations. In this way, we have constructed a Lagrangian flow network reflecting the connectivity between islands depending on the properties of the finite-size particles and comparing them with the motion of tracers. We show that the density differences, the flow properties, and the islands' position geometry substantially change the connectivity between islands. That change leads to segregating inertial particles according to their size and density. Nevertheless, the most striking observation is how the tracer transport (independently of geometry) overestimates the probabilities for specific pathways. In fact, the connectivity for inertial particles is much sparser than for tracers, such that certain pathways have extremely low probabilities; they practically do not exist. These results suggest that the transport probabilities can be highly under or overestimated by tracers' often-used approximation of inertial particles.