bluuebunny/crossref_metadata_2025 huggingface dataset:
The influence of natural climate modes on the interannual variability of the deep-water plume in the northwestern Weddell Sea
Authors: Llanillo Pedro , Kanzow Torsten , Janout Markus
Published: February 2023

A fraction of the deep-water plume that flows along the slope in the NW Weddell Sea eventually leaks from the Weddell Gyre through deep passages on its northern margin. This provides source waters for the Antarctic Bottom Water that ultimately fills the ocean abyss as the lower branch of the Meridional Overturning Circulation (MOC). Despite the importance of this supply, uncertainties still remained associated to its interannual variability. Here we investigate the role played by the combined effect of two natural climate modes in the interannual variability of the densest  water mass found within this plume, the Weddell Sea Bottom Water (WSBW). Previous studies found that both the Southern Annular Mode (SAM) and the El Niño-Southern Oscillation (ENSO) influence the winds around Antarctica, and suggested that their overlapping effects on the along-shore winds are reinforced when they occur at opposite phases (i.e. a positive SAM with a La Niña or a negative SAM with an El Niño). We prepared a combined SAM-ENSO climate index (SEI) that takes into account their overlapping effects on the winds and performed a lagged cross-correlation analysis with a 2005-2022 timeseries of WSBW thermohaline properties measured at the bottom instrument of a mooring redeployed in the NW Weddell Sea (AWI207). The significant correlations found suggest that a positive SAM occurring in summer, reinforced by a La Niña event, can influence the WSBW properties measured in the NW Weddell Sea at two different time scales. First, it would produce a warming of the WSBW reaching our mooring in the NW Weddell Sea between 4 and 5 months later. We propose that this warming is caused by the entrainment of a less modified WDW during the formation of WSBW. This is enabled by the weaker along-shore winds induced by a positive SAM and a La Niña event. Second, it would induce a freshening  of the WSBW that can be measured in the NW Weddell Sea between 13 and 14 months later. This freshening is probably related to the first mechanism proposed by McKee et al. (2011), i.e. negative anomalies in the meridional winds in the eastern side of the Antarctic Peninsula in summer would induce a reduced HSSW formation during the next winter and a decrease in the export of dense shelf waters during the next summer. However, the freshening mechanism proposed by Gordon et al., (2020), i.e. the wind-driven deepening of the V-shaped double front located at the shelf break in the western Weddell Sea, might also contribute to this freshening by enabling the injection of fresh shelf waters into the WSBW plume.
Comparison of soil organic carbon stock change with eddy covariance carbon balance at an ICOS crop ecosystem site reveals unexplained carbon losses
Authors: Loubet Benjamin , Buysse Pauline , Saby Nicolas , Ghebleh Maryam , Chenu Jean-Philippe , Ratie Céline , Jolivet Claudy , Loustau Denis , Arrouays Dominique
Published: February 2023

According to the latest estimates, soils globally store 1500 to 2400 Gt of carbon (C) at a depth of 1 m in the form of organic matter. Almost the same amount of inorganic C is estimated to be stored at a depth of 2 m. Soils contain about twice as much organic carbon as the atmosphere and three times as much as vegetation. Small changes in this large soil reservoir could therefore have major effects on atmospheric carbon dioxide (CO2) concentrations. Soil organic carbon (SOC) stocks are strongly influenced by land use, and soils have lost an estimated 140-150 Gt C globally due to disturbance and cultivation since agriculture began 8000 years ago. Global warming is disrupting the carbon cycle and could lead to a decrease in SOC worldwide. Increased nitrogen (N) deposition and intensification of N use in agriculture since the 20th century are also affecting soil inorganic carbon (SIC) stocks through carbonate weathering on agricultural sites, a process that could counteract efforts to increase SOC by changing land management.Long-term carbon observation sites, such as ICOS ecosystem sites, are unique networks for assessing soil carbon stock evolution by comparing changes in SOC stock over time through soil sampling with the annual ecosystem carbon budget combining CO2 fluxes through eddy covariance, carbon imports and exports through organic fertilization and harvesting, and dissolved carbon leaching. In this study, we compared the evolution of the SOC stock over 14 years with the carbon balance over the same period on the French crop site ICOS FR-Gri near Paris. The site is a wheat-barley-maize rotation with occasional oilseed rape. We find that SOC decreased by 68 ± 18 g C m-2 y-1 over the 14-year period in the 0-60 cm layer, with 70% of the loss coming from the 0-30 cm layer. Integration of carbon fluxes at field boundaries over the period 2006-2011 led to an estimated total carbon loss of 130 ± 110 g C m-2 y-1 in this field, an estimate close to pan-European studies (138 ± 239 g C m-2 y-1). Carbon leaching was estimated over the same period at 28 g C m-2 y-1 of which 21 g C m-2 y-1 was inorganic. The difference between the carbon balance and the SOC stock change amounts more than 50 of g C m-2 y-1, suggesting an additional carbon loss that may partly be carbonate weathering at a site that contains carbonates in part of the field.
An Integrated approach of dispersed source mapping and hyperlocal monitoring for air quality management: A case study of hotspots in Delhi
Authors: Khan Adeel , Dhandapan Sairam , Mendiratta Saurabh , Rafiuddin Mohammad , Singh Priyanka , Biswas Nimisha , Chadha Shreya , Ganguly Tanushree , Ganeshan Karthik
Published: February 2023

Limited actionable data is one of the main constraints for urban local bodies and regulatory agencies to improve air quality. Emission inventories and source apportionment are important components of air quality management. However, they provide limited information about the location of pollution sources and how the sources are changing dynamically. To overcome these limitations, a field reconnaissance survey and hyperlocal monitoring through low-cost sensors were conducted for one of the hotspots in Delhi. Field reconnaissance survey helps identify and geolocate dispersed pollution sources (unpaved roads, road dust, biomass and waste burning, construction activities, etc.). The operation of the survey includes route planning, training of field surveyors, field survey, data quality control and analysis. Through the survey, 786 dispersed sources of 14 distinct types were identified. Construction and Demolition waste, potholes, road dust and garbage dumps constitute 40 % of the sources. The concerned agencies and sub-departments were mapped through consultation with stakeholders, and sources were prioritised based on factors like population density, predominant wind direction, etc. A network of low-cost sensors is also being deployed, taking the different land use categories within the hotspot into consideration to study the impact of tackling these dispersed sources. The present approach was found to be both cost as well time effective and has the potential to scale and can be used for other scientific applications like spatial bias correction in air quality models. The approach can also be used to develop targeted strategies for improving air quality and mitigating the negative impacts of air pollution on human health and the environment.
ExoMars – WISDOM Field-Test Data Processed with Automatic Pipeline
Authors: Plettemeier Dirk , Benedix Wolf-Stefan , Hegler Sebastian , Hahnel Ronny , Statz Christoph , Lu Yun , Ciarletti Valérie , Brighi Emile , Le Gall Alice , Sall Issa , Mas Esther , Shestov Aleksey
Published: February 2023

The ExoMars Rover instrument WISDOM (“Water Ice and Subsurface Deposit Observations on Mars”) is a ground penetrating radar (GPR) designed to investigate the shallow subsurface of Oxia Planum, the ExoMars mission’s designated landing site. Using a frequency range from 0.5 GHz to 3.0 GHz the electromagnetic waves penetrate the subsurface via a wideband antenna assembly. The achieved penetration depth is at least three meters, with a depth resolution of a few centimeters. The dual-polarimetric design of the antenna allows to measure four different channels during probing the Mars soil.The WISDOM radar will give access to the geological structure, electromagnetic nature, and possibly hydrological state of the shallow subsurface by retrieving the layering and properties of the buried reflectors. A short-term subsurface analysis will support the tight schedules of the rover operations both for science and drill operations in finding places of high scientific interest and low risk.In order to achieve these short times for decision making the incoming data at the remote operation control center (ROCC) will be automatically processed through a predefined pipeline. The processing is written in Python, which uses a self-developed framework. The basic process consists of a chain of filters that produces several radargrams at different states of processing. Further, it prepares the data for storage in PDS4 format for long-term archiving.In this work, automatic processing is introduced and results of processed measurement data acquired during a WISDOM field test in Svalbard are presented.
Calibrating a 2D high-performance hydrodynamic model for fluvial process modelling along the Mekong River
Authors: Su Xiaoli , Liang Qiuhua , Jiang Jinghua
Published: February 2023

The Vietnamese Mekong Delta (VMD), representing a highly complex hydrodynamic system, plays a major role in food security and socio-economic development in Vietnam. With ongoing climate change and rapid urbanization, the VMD is increasingly vulnerable to flood risk from multiple sources, e.g. driven simultaneously by fluvial, pluvial and coastal processes. It is essential to develop reliable modelling tools to simulate such compound flooding processes to support hazard risk assessment and management to inform the development of policies and effective strategies to sustain the delta development.To support reliable compound flood modelling and risk assessment in VMD, it is important to accurately predict the fluvial processes along the Mekong River. For large river and river network modelling, one-dimensional (1D) and quasi two-dimensional (2D) hydrodynamic models are commonly used. However, modelling overbank flow and flooding process over floodplains is out of the capability of these 1D or even quasi 2D models. These 1D or quasi 2D models are then integrated with a 2D inundation model through one-way coupling to predict the flooding processes in floodplains. The resulting one-way coupled models neglect the dynamic interactions between the flows in the river and floodplain as well as upstream and downstream domains, inevitable introducing model uncertainties that are difficult to quantified and controlled. Ideally, we can use a full 2D hydrodynamic model to simulate the entirely fluvial flooding process spreading from the river channels over to the floodplains. However, this approach has not been widely reported for large-scale application due to the prohibited computational cost of a 2D hydrodynamic model.In this work, we explore the possibility of calibrating a fully 2D hydrodynamic model, the High-Performance Integrated hydrodynamic Modelling System (HiPIMS), to reproduce high, medium and low flood conditions along the middle and lower reaches of Mekong River of 55 km, starting from the Kratie gauge in Cambodia to avoid tidal influence. The model is driven by inflow at Kratie and calibrated using the measurements of both water level and discharge available at 4 gauge stations (Can Tho, My Thuan, Chau Doc, Tan Chau). The Nash-Sutcliffe efficiency (NSE) is used to quantify prediction errors to support the model calibration process.
Tectonic evolution of the Makran-Sistan triple junction: Field study and magnetostratigraphy from the Molasse-type Karvandar Basin, SE Iran
Authors: Ruh Jonas B. , Vouga Julien , Valero Luis , Najafi Mahdi , Landtwing Fabio , Guillong Marcel
Published: February 2023

The Cenozoic Karvandar Basin is situated at the intersection of the Sistan Suture Zone and the Makran accretionary wedge, in SE Iran. This intersection represents the junction of the continental Lut and Afghan/Helmand blocks in the west and east, respectively, and the northward subducting oceanic lithosphere of the Arabian plate in the south, hereafter called Makran-Sistan triple junction. The plate tectonic framework in Late Cretaceous is comparable to the present situation in the Mediterranean, with several microcontinents divided by smaller branches of the Neo-Tethys (Nain-Baft, Fannuj, Sistan, and Sabsevar oceans) surrounding the Central Iranian Blocks and the main Neo-Tethys Ocean to the south.The Karvandar Basin hosts a series of elongated, doubly-plunging growth synclines connected by variably thick shale walls while anticlinal structures are mostly absent. In this study, we unravel the tectonostratigraphic development of these synclines by geologic field investigations and precise magnetostratigraphic dating, pinpointed by U-Pb zircon ages of interlayered tuffs. Detailed information on the timing of sediment accumulation, limb rotation, and the geometry of unconformities allow identifying the character of their formation, i.e. gravitational downbuilding vs. tectonic forcing, and help understanding the tectonic context of the Karvandar Basin, specifically, how it relates to adjacent plate boundaries such as the Makran subduction zone and the Sistan Suture Zone, which is still under debate.The stratigraphic record of the Karvandar Basin is dominated by a 6-kilometer-thick sequence, showing a gentle deepening towards the west. The basin records a relatively rapid shallowing upwards trend at the base. After this first phase, the record is dominated by shallow marine to non-marine alluvial Molasse-like sediments. During this phase, the sedimentary environment remained steady for thousands of meters, suggesting a balance between accommodation and sedimentation. This reveals a fast and steady subsiding system, and points to high sedimentation rates and an expanded stratigraphy.Magnetostratigraphic dating of a approx. 4km sedimentary sequence suggests that the basin formed between ~23–17 Ma, resulting in an accumulation rate of ~1 m/kyr. Angular blocks of volcanic heritage and corrals in the underlaying shale potentially suggest an olistostrome nature with a respective age >24 Ma. We propose that the closure of the South Sistan Basin and the related orogeny led to tectonic subsidence, where a Molasse-type continental sequence was deposited onto a kilometer-thick, mechanically weak olistostrome.
Large-scale thermo-mechanical modelling of Greenland ice sheet
Authors: Utkin Ivan , Räss Ludovic , Werder Mauro
Published: February 2023

Antarctic and Greenland ice sheets lose most of their mass by a few corridors of rapidly flowing ice. These ice conveyor belts constitute fast drainage routes whose flow velocities are undoubtedly sensitive to climate perturbations directly impacting sea-level. Observations suggest the ice is rather sliding than flowing, the key being where sliding is accommodated. Commonly, sliding occurs at the ice-bedrock interface, but recent studies favour englacial sliding to explain data from Western Margin of Greenland. Our aim is to demonstrate that the mechanisms controlling the spontaneous formation of englacial sliding explains the transition from slow flowing to fast sliding ice over Greenland. We employ a new thermo-mechanical ice flow model to predict thermally activated creep instability leading to the spontaneous rearrangement of ice motion in three dimensions. Accurately resolving these nonlinear interactions on regional to ice sheet scales requires high spatial and temporal resolution which can only be achieved using a supercomputer.We present a new thermo-mechanical ice flow model, FastIce.jl, that is capable of predicting the evolution of ice sheet at unprecedented scale. The model uses the full-Stokes formulation for the ice flow and the enthalpy method for describing the polythermal ice behaviour. FastIce.jl uses GPU acceleration for solving the flow equations, resulting in close to ideal scaling in distributed computing benchmarks. We compare our simulation results with other full-Stokes models, and present the results of simulating the 120x120 km regions of Greenland ice sheet at 10m resolution. High resolution allowed us to capture the transition from slow to sliding flow regimes without any simplifying assumptions.
Property level pluvial flood risk estimation from large-scale flood models - Identifying potential erroneous locations using a geospatial postprocessing algorithm
Authors: Muthusamy Manoranjan , Bartholomew Ian
Published: February 2023

A distinctive characteristic of 2D flood models used in catastrophic modelling in industries such as re/insurance is that they are often developed for a national, continental or even global scale (hereafter referred to as large-scale models). Traditionally these models were used at portfolio-level loss estimations. However, the increased need for understanding flood risk at a much smaller scale (e.g., at the property level), especially for parametric insurance products demands these models to deliver high-resolution, high-accurate flood inundation mapping. Although technological advancements in remote sensing and cloud computing have made this possible to a certain extent, the underlying models are still large-scale models with inherent uncertainties caused by unaccounted small-scale dynamics in both hydrometeorological and terrain data that are impossible to be captured by these large-scale models. Although this uncertainty exists in all three sources of floods (fluvial, pluvial and coastal), pluvial floods' sensitivity to drainage structures and small-scale dynamics in terrain - both of which are poorly represented in large-scale models - make them the most vulnerable flood type to this uncertainty.  

We attempt to develop a novel and practical geospatial approach to identify cases where large-scale 2D flood models are likely to underestimate/miss pluvial flood risk at the property level using easy-to-calculate proxies. These proxies are derived from the inundation clusters created using the 2D flood map itself - hence they do not need any additional data. To test the method, we used data collected from FloodFlash’s novel and low-cost flood depth sensors installed at properties across the UK. Initial results show that the method is able to identify more than 75% of the cases where the large-scale flood maps underestimated flood risk at the property level (Hits). This method is currently being improved to reduce the number of false positives by finetuning the selected proxies. 
Measuring Atmospheric Hydrogen Ahead of the Anticipated Hydrogen Economy
Authors: Mitrevski Blagoj , Guerette Elise-Andree , Langenfelds Ray , Woodhouse Matthew , Spenser Darren , Krummel Paul , Steele Paul
Published: February 2023

The continuous population and economy growth demands more energy, currently provided predominantly by burning of fossil fuels. However, the depletion of fossil fuel resources and the detrimental environmental impacts of burning fossil fuels are driving the public opinion and governments towards renewable energy (RE) sources. Solar and wind power are the most promising, but its reliability is shadowed by their weather dependence. Hydrogen is considered as a very promising energy carrier which can overcome the limitations of the existing RE sources. Producing hydrogen at the solar panel fields or incorporating water electrolysers within wind turbines will smooth the energy supply, and even reduce the energy transport. If the hydrogen economy takes effect as anticipated, then the hydrogen impact on the climate needs to be re-assessed. In order to simulate future hydrogen concentrations, it is necessary to build a model which can simulate present day hydrogen emissions and sinks, and resultant atmospheric concentrations, which are currently infrequently measured. Building a history of hydrogen measurements opens up possibilities in the future to determine background and pre-existing hydrogen sources, and gives a baseline before the switch to a hydrogen economy.Historically, Reduction Gas Analysers (RGA) were the workhorse in the laboratory and field, where reductive gasses like hydrogen or carbon monoxide release mercury gas by passing along a heated solid mercuric oxide bed, which in turn is analysed by ultraviolet (UV) absorption. The method is well established but lacks linear response and stability. CSIRO is working on novel methods for more accurate and precise hydrogen measurement. The Pulsed Discharge Helium Ionization Detector, or simply PDD, is an alternative to the RGA. CSIRO has been operating a PDD for hydrogen at Cape Grim (along with the classic RGA) for 7.5 years using shared calibration tanks. The mean difference between them (50,000+ matched data points, when pollution events are removed) is just 0.02 ppb, proving PDD’s incredible compatibility with the established RGA technique. The PDD also has a demonstrated superior precision and linearity compared to the RGA. Another two PDD systems are operational at Aspendale measuring urban hydrogen since 2019 and 2021. The later one is to be deployed at the CSIRO Clayton site, where Aspendale will relocate to in 2025. Another PDD system is in a development stage, able to measure not just hydrogen, but many other atmospheric gases (CH4, CO2, N2O, Kr, Xe). The inability of optical instruments to measure hydrogen (homonuclear diatomic molecule) will mean that there will be an increased demand for RGA or PDD measurements of hydrogen in the future.
Reduced Basis Methods for Optimal Control Problems with Random Inputs in Environmental Science
Authors: Carere Giuseppe
Published: February 2023

We study methods that aim to reduce the dimension of a finite dimensional solution space, in which the solution corresponding to a certain parametrized Optimal Control Problems governed by environmental models, e.g. Quasi-Geostrophic flow, is sought. The parameter is modeled as a random variable to incorporate possible uncertainty, for example in parametric measurements. For such a reduction to be useful, it should be guaranteed, for every possible parameter value, that it results in an acceleration of the solution process while maintaining an accurate approximate solution. In order to do this, conditions are formulated, and under those conditions, several versions of a specific reduction method known as Proper Orthogonal Decomposition are implemented. We consider examples and show that a simplification of the general state of the art reduction method performs equally well.
The triggers for Conger Ice Shelf demise: long-term weakening vs. short-term collapse
Authors: Lhermitte Stef , Wouters Bert , Team HiRISE
Published: February 2023

Ice shelf instability is a key uncertainty in future sea level rise projections, as several small-scale processes leading to ice shelf collapse remain poorly quantified. Historical large scale ice shelf collapses, like the Conger Ice Shelf collapse in March 2022, therefore, provide unique insights in the processes leading to ice shelf instability.In this study, we assess the long- and short-term changes on Conger Ice Shelf in historical satellite records (Landsat, Sentinel, MODIS, ICESat) and model output of ocean and climate conditions (HYCOM, RACMO, IMAU-FDM and ERA-5). Based on both observations and model output we determine the role of known ice shelf instability processes like hydrofracturing, basal melting and damage changes. Moreover, we evaluate the role of extreme weather and ocean conditions in the sudden Conger Ice Shelf collapse.The longer satellite record shows that Conger Ice Shelf has been weakening for years and then collapsed in two abrupt events (2 and 15 of March 2022). The long-term weakening is the result of damage processes and calving events due to extreme ocean/weather conditions that gradually abate the ice shelf. The abrupt Conger Ice Shelf collapse, however, coincides with extreme atmospheric and ocean conditions (e.g., ocean slope and wave conditions) that trigger the weakened ice shelf into a sudden collapse. Our results show that the known ice shelf instability processes like hydrofracturing and basal melting do not play a key role in the abrupt Conger Ice Shelf collapse, but that gradual weakening followed by extreme weather and ocean conditions triggered the ice shelf collapse.Our results stress the importance of separating ice shelf weakening from ice shelf collapse in studies of ice shelf stability. Moreover, they imply that extreme weather and oceanic conditions need to be to considered when assessing the future vulnerability of Antarctic ice shelves to collapse.
Toward high resolution and daily thermal infrared measurements for agricultural water management
Authors: Ziliani Matteo G. , Werner Florian , Abelló Albert
Published: February 2023

Sustainable water use in agriculture, while ensuring high yield returns, is key to tackling challenges imposed by climate change and population growth. Knowing the crop water status within the field allows for optimized water consumption by matching management practices to the actual crop water demand. Science and applications communities have made clear the needs and requirements for daily, field-scale (< 100 m) evapotranspiration (ET) data for agricultural applications. Current and planned space missions with thermal infrared (TIR) measurements either have high-spatial or high- temporal resolution, but not both, making it hard to capture the field-scale variability required for irrigation and crop growth modeling.Hydrosat has innovated through the technical barriers to achieving field-scale, global TIR and VNIR measurements for ET every day, multiple times per day. With an upcoming launch en route to a 16+ smallsat constellation, Hydrosat data will be a game-changer and will significantly advance our ability to monitor and manage agricultural systems. An Early Adopter daily 20-m surface temperature product is already available now and can be used to accurately track crop water supply and demand within a specific field.Here we show the potential of a new method that combines the spatio-temporal advantage of Hydrosat Early Adopter (along with freely available satellite data) with the predictive ability of crop model simulations to overcome the limitations of existing methods of irrigation management at the field and sub-field levels. The method was validated over multiple corn fields in the US Corn Belt, exploring a wide range of environmental conditions and management practices and across multiple growing seasons (2019-2021). ET, soil moisture, and yield data collected during the season were used for validation.First, high spatio-temporal resolution thermal and multispectral satellite data were used to derive ET and leaf area index (LAI) during the crop growing season. Using these products, phenological development and soil-water components of the APSIM crop model were calibrated to accurately determine (and improve upon) farm-level predictions, both in terms of soil moisture content and end-of-season yield. Our method successfully estimated soil moisture with high accuracy (RMSE of 1.43 mm/mm and rRMSE of 7.47 %) and predicted yield reliably up to 14 weeks before harvest, with a strong correlation to independently collected measurements (RMSE of 1162 kg/ha and rRMSE of 7 %). The proposed approach has the potential for driving irrigation management decisions while quantifying end-of-season yield without the need for in situ data.
The set up of the “UNO” project relational database for Stromboli volcano
Authors: Tarquini Simone , Martinelli Francesco , Bisson Marina , De Beni Emanuela , Spinetti Claudia , Tarabusi Gabriele
Published: February 2023

Active volcanoes are complex, poorly predictable systems that can pose a threat to humans and their infrastructures. As such, it is important to improve as much as possible the understanding of their behavior. The Stromboli volcano, in Italy, is one of the most active volcanoes in the world, and its almost persistent activity is documented since centuries. The persistent background activity is sometimes interrupted by much more energetic, dangerous episodes. The Istituto Nazionale di Geofisica e Vulcanologia (Italy) set up the interdisciplinary “UNO” project, aimed to understand when the Stromboli volcano is about to switch from the ordinary to the extraordinary activity. The UNO project includes an outstanding variety of research activities, such as sampling in the field, the modeling of Stromboli topography from ALS technique and satellite data, the 3D numerical simulations of ballistic trajectories, or the set up of an ultrasonic microphones system. Key to the success of the project is the collection of integrated high spatial and temporal resolution data and their joint analyses in a shared relational database. We present here the simplified logical model of such database, focusing on the identification of entities and their relationships.
Concepts of geodiversity and biodiversity interactions across different scales
Authors: Canessa Rafaella , Ehlers Todd A. , Kraus Diana , Dippold Michaela A. , Oelmann Yvonne , Tielbörger Katja
Published: February 2023

It has been proposed that geodiversity (the diversity of geological, geomorphological and pedological features) is positively correlated with biodiversity. This suggests that by preserving geodiversity, we can also preserve biodiversity and the associated ecosystem functions. However, a significant correlation between geodiversity and biodiversity measures does not mean causation and does not distinguish spatial and temporal scale dependencies of the processes involved. In fact, such a correlation could also imply that biodiversity estimates can predict geodiversity. These aspects have, nonetheless, rarely been considered in geo- and biodiversity studies, which constrains the applicability of these analyses in, for example, models of geo- and biodiversity distribution that rely on explicit processes. We aim to explore the interactions between geo- and biodiversity across different scales, identifying the key mechanisms that link them.

The feedbacks between geodiversity and biodiversity start at the microscale during the process of soil aggregation and formation, driven by microbial diversity such as fungi and biological soil crusts, as well as by plant roots. On the other hand, soil texture defines microsites for microbial life, and surface types and quality shape their colonization process. At intermediate landform or catchment scales, the spatial variability of topographical, lithological and soil features benefits the formation of diverse habitats and resources for biota (e.g. plants, vertebrates and invertebrates), which, at the same time, will affect radiation distribution, erosion and nutrient availability. At even larger scales, processes like mantle dynamics and the number of plate boundaries can determine regional-scale shifts in ecosystems, isolation processes and the evolution of biota. Similarly, temporal variability determined by, e.g. microclimate, catchment scale meteorology or orographic effects, induces niche variability within a spatial scale. Finally, based on these process-related relationships at variable scales, we suggest a list of geodiversity parameters to be used when assessing geo- and biodiversity interactions.
Enhancing Urban Resilience to flooding using Afforestation: the case of Nouakchott city, Mauritania
Authors: Perona Paolo , Dubois Emmanuel , Marshall Montana , Boukhreiss Fatimetou , Ahmed Cherif Saleck Moulaye , Chenal Jerôme , Grossiord Charlotte
Published: February 2023

Despite a warm and dry climate, the city of Nouakchott has been facing constant flooding for almost a decade, making part of the city inhabitable and posing long-term health threats. Groundwater levels are relatively constant over the year, except for October, when the groundwater table rises at the end of the rainy season, resulting in an almost doubled flooded area in the city compared to drier periods. Saltwater intrusion maintains a constant level in the water table beneath the city. However, the infiltration of most of Nouakchott’s used water acts as systematic artificial aquifer recharge, thus increasing the risk of groundwater saturation excess and flooding. Hence, in comparison to the driest decade (1971-1980), flooding in the city today cannot only be attributed to the slight increase in precipitation over the last decade. This project hypothesizes that increasing the resilience to urban flooding in the city of Nouakchott can be achieved by using salt-tolerant plants to lower the water table level. This work presents a joined interdisciplinary ecohydrology and plant physiology approach for monitoring and modeling the transpiration and dewatering capacity of different local tree species. The project aims to provide scenarios for an integrated and sustainable afforestation strategy for Nouakchott. In addition to increasing the city’s resilience to flooding, the role that afforestation could play to enhance the provision of sustainable services for the people and the economy (e.g., shade in the streets, potential fruit harvesting and wood market, etc.) will also be discussed. The first field campaign of the project allowed to monitor five observation wells with automatic water depth measurements and 12 sap flow sensors on three tree species. Eventually, to reinforce the relatively scarce groundwater data, a spatiotemporal time series of the city's flooded areas was also reconstructed using remote sensing data, and its reliability to calibrate an eco-hydrogeological model will be discussed.
Dissolved organic sulfur utilization by marine benthic microbial communities revealed by quantitative DNA stable isotope probing
Authors: Coskun Ömer Kürsat , Orsi William D. , D'Hondt Steve , Gomez-Saez Gonzalo V.
Published: February 2023

Microbial metabolisms are directly responsible for the production, degradation and recycling of dissolved organic matter (DOM) in the ocean. Many compounds within the DOM contain sulfur (dissolved organic sulfur, DOS) and in sum they represent the largest reservoir of organic sulfur in the ocean. Recent studies indicated an abundant and diverse suite of marine bacteria with the genetic capacity for DOS transformation. However, there is currently very little experimental data regarding the marine sediment microbial communities that are actively using DOS substrates as a source of carbon. Here, we use quantitative 13C DNA stable isotope probing (qSIP) to provide the first quantitative measurements of DOS (taurine and methionine) utilization by specific operational taxonomic units in seafloor sediments from continental shelf of Puerto Rico (493 meter below sea surface). Immediately after sampling, seafloor sediments were amended with 500 µg / g 13C-labeled taurine or methionine as well as natural-abundant (12C) substrates as a control and were incubated in gas-tight glass flasks with no headspace in the dark over two different timepoints (30 hours and 10 days) to unravel the active microbial communities. Our preliminary results by gas-chromatography mass spectrometry showed that there was 6 – 10% of 13CO2-remineralization compared to control samples. This indicates that taurine and methionine are important DOS substrates supporting the activity of benthic microbial populations. Notably, the rate of taurine remineralization was five-fold higher than glucose and 50-fold higher than methionine over the first 30-hours of incubation, suggesting that taurine is an underappreciated, yet important DOS substrate for microbial activity at the seafloor. Oxygen was rapidly consumed to anoxic levels over the first 12 hours in all incubations, indicating that the taurine was utilized via anaerobic microbial metabolism. This was reflected by changes in the initial microbial community that was dominated by Thaumarchaeota (29%), Gammaproteobacteria (15%) and Planctomycetes (13%), which changed to being enriched by Firmicutes (8%-43%), Deltaproteobacteria (10%-26%), and Gammaproteobacteria (10%-29%) in the presence of taurine and methionine. Further quantitative DNA isotope probing study (in progress) will reveal the specific anaerobic microbial taxa that are responsible for driving the biogeochemical cycling of these important, yet overlooked DOS substrates at the seafloor.
The Student-Led Design and Testing of an Imaging CubeSat Payload
Authors: Watson Matthew , Hunter Thomas ,   PROVE Team
Published: February 2023

Volcanic ash presents a challenge for the aviation industry. 3D information is needed to be able to back-calculate dose – this is a key parameter in managing airspace. To recreate the ash cloud, multiangle observations are required – deal to perform visual and infrared observations. Other mission objectives using the can also be realised, for example, as volcanic ash clouds are the primary target, there is the possibility to map new magma extrusions, lava and pyroclastic flow movements. Thermal infrared data has also previously been used to observe volcanic cycles and better understand their behaviour. The visual images required for 3D construction of ash clouds can be used to create digital elevation models of terrain around volcanos which have application in disaster management and planning, and forest fires may also be included as targets of opportunity.
A CubeSat mission - Pointable Radiometer for Observing Volcanic Emissions (PROVE) Pathfinder - is proposed to monitor the ash cloud using both thermal infrared and visual cameras. The resulting 2U payload consists of a thermal infrared camera (FLIR Tau 2 with a 50mm lens) and a visual camera (a narrow field of view Basler ace ac5472-5gc with a Kowa LM75HC lens). Alongside this, a payload computer to communicate with the cameras and store data was selected (the BeagleBone Black Enhanced Industrial) with a custom PCB providing connections to the instruments and bus. The software to operate the payload takes the form of a custom scheduler for an imaging pass, sending commands to the camera systems (and to the bus) to take the required multiangle images for ash cloud reconstruction.
The engineering model of the payload is currently being tested at the European Space Agency’s CubeSat Support Facility with the support of the Education Office of the European Space Agency under the educational Fly Your Satellite! Test Opportunities programme. The team are undertaking a month of environmental testing including vibration and thermal vacuum tests. The aim of the testing campaign is to qualify the payload for launch.
Currents, mélange and iceberg calving in Greenland fjords: new insights to a self-organised critical system
Authors: Christoffersen Poul , Lee Seungbong , Cook Samuel , Truffer Martin
Published: February 2023

Flow and mass balance of the Greenland Ice Sheet are largely controlled by marine-terminating glaciers that deliver large quantities of ice into fjords and coastal seas. The interaction of these glaciers with the ocean is crucial because heat and circulation in fjords drive high rates of melting. However, the links between warm ambient fjord water, subaqueous melting and iceberg calving are poorly understood. Here, we report a detailed record of surface circulation in Ikerasak Fjord, West Greenland, by tracking the displacements of icebergs in radar imagery acquired with a terrestrial radar interferometer, which also produced a detailed record of iceberg calving from Store Glacier. With images captured every three minutes, we derived fjord circulation and calving rates with unusually high temporal resolution. In the first of three periods, we observed low-speed surface currents (<0.15 m/s) together with high calving activity (around 50 events per hour) as a response to the break-up of proglacial winter melange. We subsequently observed faster surface currents (up to 0.57 m/s) but much less calving (<20 icebergs per hour). Later, as currents intensified and a large eddy formed, we observed a combination of fast fjord circulation (around 0.4 m/s) and high calving activity (20-40 events per hour). The record shows that calving is a self-organised critical system, with small icebergs produced continuously in a critical state, whereas large icebergs were produced mostly when calving becomes super-critical. A super-critical state was reached when the melange broke up and later as the eddy formed in front of the glacier. In this state, we found stronger fjord circulation to drive more frequent calving events, while more frequent calving in general caused a higher flux of ice to the ocean.
Monitoring natural and geo- hazards at cultural heritage sites using Earth observation: the case study of Choirokoitia, Cyprus
Authors: Themistocleous Kyriacos , Fotiou Kyriaki , Tzouvaras Marios
Published: February 2023

Monitoring natural hazards due to climate change and natural hazards at cultural heritage sites facilitates the early recognition of potential risks and enables effective conservation monitoring and planning. Landslides, earthquakes, rock falls, ground subsidence and erosion are the predominant natural hazards in Cyprus, which pose serious disadvantages to cultural heritage sites as well as potential danger to visitors. To identify and monitor natural hazards and environmental displacements Earth observation techniques, such as SAR, can be used in combination with in-situ methods.The EXCELSIOR H2020 Widespread Teaming project under Grant Agreement No 857510 and the TRIQUETRA project Horizon Europe, Grant Agreement No. 101094818 will study the use of Earth observation techniques for examining cultural heritage sites. The TRIQUETRA project will examine Choirokoitia, Cyprus as a pilot project using these techniques. Choirokoitia is a UNESCO World Heritage Site and is one of the best-preserved Neolithic sites in the Mediterranean. The project will examine the potential risk of rockfall at the Choirokoitia site, as the topology of the site is vulnerable to movements as a result of extreme climate change as well as of daily/seasonal stressing actions. Rockfall poses a significant danger to visitor safety as well as damage to cultural heritage sites.As well, the Choirokoitia site will be used to detect and analyse natural hazards induced ground deformation based on InSAR ground motion data and field survey techniques for cultural heritage applications. InSAR data, satellite positioning and conventional surveying techniques will be employed to measure micromovements, while other techniques such as UAVs and photogrammetry will be used for documentation purposes and 3D modelling comparisons. In order to identify and monitor natural hazards and their severity, a permanent GNSS station and corner reflector, as well as analysing multitemporal SAR satellite data will be used to estimate the rate of land movement. SAR monitoring provides the opportunity to identify deformation phenomena resulting from natural hazards for monitoring and assessing potential hazards using remote sensing techniques to measure and document the extent of change caused by the natural and/or geo-hazards. PSI (Persistent Scatterer Interferometry) analysis can be used in the wider area to determine potential displacements.The study is expected to lead towards the systematic monitoring of geohazards, and more specifically those of ground deformation and rock falls to facilitate the early recognition of potential risks and enable effective conservation monitoring and planning. The methodology can be used to monitor cultural heritage sites worldwide which are vulnerable to natural hazards.
Review of methods for characterization of active faults for seismic hazard purposes.
Authors: Ornelas Agrela Adriana Fatima , Benito María Belén , Lindholm Conrad
Published: February 2023

This work presents a review of some methods for seismic hazard assessments based on hybrid source models, composed of active faults and seismic zones. These approaches are applied in a slow deformation area, defined as areas where the slip rate of the active faults is slower than 5 mm/yr.The introduction of active faults as independent seismic sources in seismic hazard assessment has a great impact on the results that can be obtained in urban areas close to active faults, with respect with those obtained with classical zoning methods (CZM). Currently, there are no widely contrasted methodological developments to include zones and the characterized active faults in the source models, especially in slow deforming areas. Even though, some approaches that have used hybrid models (HM) composed of zone-type sources and fault-type sources, revealed that expected ground motion values around main faults may double (on average) those obtained by zoned models, in agreement with observations in recent earthquakes (Rivas-Medina, A., 2018; Gómez-Novell O., 2020).This presentation compares some methods that address two key aspects: how to quantify the geological information and transfer it to recurrence models, and how to distribute the seismic potential between the two types of sources. Some of these methods are: 1) Moment-rate based method proposed by Bungum (2007), 2) Slip-rate based method also proposed by Bungum (2007), 3) Hybrid method developed by Rivas-Medina et al. (2019).This study is centered in the Eastern Betics Shear Zone (EBSZ) in southeast Spain, which is a low to moderate seismicity region. These methods were applied in the seismic zones 37 and 55 defined by Garcia-Mayordomo (2015) due to the seismological and geological data availability of the present faults in each zone.
The combined surveying of soil CO2 flux and air CO2 concentration for gas hazard mitigation at Vulcano, Italy
Authors: Camarda Marco , Gurrieri Sergio , Di Martino Roberto M.R. , Francofonte Vincenzo
Published: February 2023

Among extreme geological events, people feel the effects of volcanic eruptions through fear and wonder. Several volcanoes erupt across the world with sheer physical power, but a large part of them is either dormant or quiescent. Risks for explosions at active volcanoes are well-recognized, while the gas hazard which is correlated with almost continuous gas emissions from either the crater cone or the soils is still a masked risk. Volcanic gas emissions impact people at settled zones which lay around the main quiescent volcanic structure. In addition, the level of the gas hazard correlates with changes in the gas emissions, which agrees with variations of the magmatic degassing at depth.This study reports on the results of the continuous monitoring for soil CO2 flux, air CO2 concentration, and some weather variables (i.e., temperature, pressure, relative humidity, wind speed, and wind direction). Tailored monitoring stations were deployed in an anomalous degassing zone of the island of Vulcano, Italy (i.e., Faraglione) for mitigating the gas hazard. This area hosts many infrastructures and several tourist facilities. The deployment of the monitoring network occurred in June 2021 in the framework of the agreement between the Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Palermo, and the Dipartimento Regionale di Protezione Civile (DRPC – Sicilia).Since late September 2021, the volcanic degassing increased at Vulcano due to a probable increase of the magmatic degassing at depth. The results of this study show a distinct increase in the soil CO2 flux at Faraglione which correlated with the high CO2 concentration in the air. These variations caused increases in the gas hazard at Vulcano. Besides various evidence points to the climax of the volcanic unrest in autumn 2021, redundancy for monitoring stations in the anomalous degassing zone allowed capturing of some minor variations of the magmatic activity at depth. Some remarkable increases occurred in soil CO2 emissions during spring 2022, which culminated in the whitening of the seafloor at Baia di Levante. Minor variations are reported for both summer and early autumn 2022. These results point out as both the accurate monitoring of the air CO2 concentration and the weather variables complement efficiently the continuous monitoring of the soil CO2 flux resulting in a suitable strategy for mitigating the gas hazard at Vulcano.