bluuebunny/crossref_metadata_2025 huggingface dataset:
Metal contamination of urban soils in Cork, Ireland
Authors: Binner Hannah , Sullivan Timothy , Mc Namara Maria E.
Published: March 2021

Soil contamination is widespread across Europe. In particular, contamination of urban soils by metals is poorly characterised. This is a major environmental concern, especially given that urban recreational amenities may be located on former industrial sites and/or may possess ex situ soils derived from industrial areas. We surveyed soils from nine urban recreational sites (15 samples per site) in Cork city in order to assess the degree of metal contamination. The results show that Pb concentrations exceed national background levels in all soil samples from all sites by a mean of 600 % and at least 140 %. Mn, Fe and Zn are enriched above background levels in all soil samples from three (Mn and Fe) to five (Zn) of the sites and, at the remaining sites, show 7 – 14 localised hotspots. Similar hotspots characterise Cu, Rb and Sr, which each exceed background levels at eight or more sampling locations at four sites. Co, Ni, As and Sn concentrations exceed background levels in at least three hotspots at each of three to six sites. Overall, metal concentrations are highest in the sites closest to the city centre, reflecting diverse sources that potentially include traffic and current and historical domestic coal burning and industry. At each urban site, the element grouping Zn and Pb recurs in 50 to 80 % of locations and enrichment in the element grouping Mn, Fe, Cu, Zn and Pb recurs in approx. 50 % of locations; Ni and As recur in approx. 10 % of the locations. At three sites, elevated concentrations of Mn, Fe, Cu, Zn and Pb are associated with high LOI (Loss-on-ignition) values – a proxy for the amount of soil organic matter present – and near-neutral pH values. Conversely, low LOI and acidic pH values are associated with lower concentrations of these elements. This indicates that soil metal concentrations are influenced by the amount of organic matter present and by pH.  Future analyses and experiments will further investigate links between soil organic matter and metal concentrations.
Collecting training data to map forest management at global scale
Authors: Lesiv Myroslava , Schepaschenko Dmitry , Dürauer Martina , Buchhorn Marcel , Georgieva Ivelina , Fritz Steffen
Published: March 2021

Spatially explicit information on forest management at a global scale is critical for understanding the current status of forests for sustainable forest management and restoration. Whereas remotely sensed based datasets, developed by applying ML and AI algorithms, can successfully depict tree cover and other land cover types, it has not yet been used to depict untouched forest and different degrees of forest management. We show for the first time that with sufficient training data derived from very high-resolution imagery a differentiation within the tree cover class of various levels of forest management is possible.

In this session, we would like to present our approach for labeling forest related training data by using Geo-Wiki application (https://www.geo-wiki.org/). Moreover, we would like to share a new open global training data set on forest management we collected from a series of Geo-Wiki campaigns. In February 2019, we organized an expert workshop to (1) discuss the variety of forest management practices that take place in different parts of the world; (2) generalize the definitions for the application at global scale; (3) finalize the Geo-Wiki interface for the crowdsourcing campaigns; and (4) build a data set of control points (or the expert data set), which we used later to monitor the quality of the crowdsourced contributions by the volunteers. We involved forest experts from different regions around the world to explore what types of forest management information could be collected from visual interpretation of very high-resolution images from Google Maps and Microsoft Bing, in combination with Sentinel time series and Normalized Difference Vegetation Index (NDVI) profiles derived from Google Earth Engine (GEE). Based on the results of this analysis, we expanded these campaigns by involving a broader group of participants, mainly people recruited from remote sensing, geography and forest research institutes and universities.

In total, we collected forest data for approximately 230 000 locations globally. These data are of sufficient density and quality and therefore could be used in many ML and AI applications for forests at regional and local scale.  We also provide an example of ML application, a remotely sensed based global forest management map at a 100 m resolution (PROBA-V) for the year 2015. It includes such classes as intact forests, forests with signs of human impact, including clear cuts and logging, replanted forest, woody plantations with a rotation period up to 15 years, oil palms and agroforestry. The results of independent statistical validation show that the map’s overall accuracy is 81%.
Adaptation to climate change in the mountain regions of Central Asia: Assessment of the current knowledge
Authors: Saidaliyeva Zarina , Muccione Veruska , Shahgedanova Maria , Bigler Sophie , Adler Carolina
Published: March 2021

The mountains of Central Asia, extending over 7000 m a.s.l. and accommodating diverse and complex natural and managed systems, are very vulnerable to climate change. They support valuable environmental functions and provide key ecosystem goods and services to the arid downstream regions which strongly depend on the melting snowpack and glaciers for the provision of water by the transboundary rivers starting in the mountains. Strong climate change adaptation (CCA) action is required to increase resilience of the vulnerable, low-income communities in the region. Our knowledge of the CCA actions in the mountains of Central Asia is limited in comparison with other mountainous regions. The aim of this study is to assess the existing adaptation projects and publications and to identify gaps in adaptation efforts by conducting a systematic review of the peer-reviewed literature published in English language. To be selected, the papers had to comply with the following criteria: (i) publication between 2013 and 2019; (ii) explicit focus on CCA in the mountain ranges of Central Asia; (iii) explanation of adaptation options; (vi) a clear methodology of deriving suitable adaptation options. Following the initial screening and subsequent reading of the publications, complying with the specified criteria, 33 peer-reviewed articles were selected for final analysis. This is considerably lower than the number of publications on the European Alps, Hindu-Kush – Himalayas, and the Andes. The number of publications on Central Asian mountains has declined since 2013.

The research is heavily focused on the problem of water resources, especially water availability at present and in the future 70 % of the analysed papers addressing these issues. These are followed by the papers considering adaptation in agriculture and in managing biodiversity. A critical finding is the lack of publications on adaptation to hazards and disasters including glacier outburst floods, mudflow, and landslides which are common and comparatively well-researched hazards in the Central Asian mountains, experiencing rapid deglaciation. About 50 % of the papers address the transboundary nature of the impacts of climate changes on water resources and land management reflecting the transboundary nature of the Central Asian catchments and the tensions which exist across the region but are especially prominent in the Aral Sea basin.

We conclude that while there is ample evidence of climate change and its impacts in the mountains of Central Asia and many publications mention the need for adaptation, a very limited number of publications explicitly focus on CCA and how it can be delivered.
Laboratory test results of a new developed low-cost and open-source inclinometer based on MEMS technology
Authors: Ruzza Giuseppe , Revellino Paola , Guadagno Francesco Maria
Published: March 2021

The stationary or in-place inclinometer is the main high-performance solution in landslide monitoring applications due to its capability of tracking real time displacement at different depth and supporting early warning. Despite that and the general need of data for understanding landslide behaviour, the high cost of in-place inclinometers, in most cases, limit or prevent their use. On this basis, we started developing a low-cost and open source, modular MEMS-based inclinometer that uses multiple Arduino boards as processing units. Although MEMS accelerometers have many advantages in comparison with traditional high-precision electromechanical sensors, they are very sensible to temperature variation (i.e. thermal drifting).

In order to compensating thermal drifting a specific thermal analysis and an associated simple compensation strategy were used. After the mitigation of thermal bias, the electronic devices were designed, built and assembled.

The developed inclinometer system is composed of two main electronic systems: 1) a multiple electronic device (i.e. a MEMS accelerometer, the IMU reading interface and a communication board) installed within each measuring module; 2) an external master control unit, based on the Arduino platform coupled with a dedicated developed interface board. The master unit reads tilt value from each measuring module through a communication interface. This unit was developed to allow interfacing of additional digital or analog sensors (e.g. water content, rain gauge, etc..), and control additional parameters.

A steel casing for measuring components was designed and built. For each measuring unit, a squared-section case, consisting of a 30 cm long tube equipped with 4 elements that allow the installation the instrument within a standard inclinometric tubes, was prepared and assembled.

After system assembling, displacement of the inclinometric column was first simulated by a laboratory test. In particular, we used a supporting frame that allowed to vertically align the modules. The auxiliary frame was specifically designed to drive displacement along a selected axis and to register the maximum displacement at the head of the inclinometric column. In this way, the lower module is kept fixed. This test permitted to obtain a number of different synthetic deformation curves that form a basis for checking the accuracy of the instrumentation measurement. Result obtained highlight the potential use of our system for real monitoring application. The next step will be to install the instrumentation on site to check its operation in real field conditions.
A new data set for the Brewer spectrophotometer uncertainty budget in the total ozone column measurements
Authors: Parra-Rojas Francisco Carlos , Redondas Alberto , Berjón Alberto , López-Solano Javier
Published: March 2021

Brewer spectrophotometers are one of the most widely used instruments for measuring the Total Ozone Column (TOC) in the world, which is obtained by measuring solar radiance at a set of UV sensible wavelengths. To date, the value of the uncertainty in these measures has not been obtained quantitatively. With this work, we have carried out an exhaustive study of the uncertainties that have affected the measure of TOC with data obtained during the first ATMOZ field campaign carried out between 12-25 September 2016 at the Izaña Atmospheric Observatory, Canary Islands, Spain at 2373 m.a.s.l., organized by the Spanish Meteorological Agency (AEMET) and the World Radiation Center (PMOD/WRC). For this, we have differentiated between three uncertainty components: related to the measure (dead time, filters, etc), model components (cross sections, etc) and atmospheric components (effective temperatures and heights, etc). The total uncertainty has been obtained through the propagation of errors of the different parameters, and the cross-correlations between the model and atmospheric components, using two different data sets. With the standard algorithm we have obtained the expected 2σ-uncertainty, around 2.4% for the three RBCC-E Triad Brewer double-monochromator spectrophotometers studied (Br157, Br183 and Br185) at noon and using the Extra-Terrestrial Constant (ETC) Langley calibration. On the other hand, for these same spectrophotometers, and using an updated algorithm the 2σ-uncertainty are reduced to values around 1.3 % in the TOC measurement. In first approximation, ignoring the cross-correlations the ozone absorption coefficient covers the most of total ozone uncertainty in both algorithms, followed by the ozone optical mass, the ETC and the measurement uncertainties.
Future changes in European windstorm severities and impacts 
Authors: Catto Jennifer , Little Alex , Priestley Matthew
Published: March 2021

Extratropical cyclones that impact Europe are significant natural hazards that can cause severe damages and lead to large socio-economic losses. There are large uncertainties associated with changes in storm number, and storm intensity, in future climate projections. Here we use a Lagrangian tracking algorithm applied to reanalysis data and to historical and two future scenario simulations of a number of CMIP6 models to investigate future changes in characteristics of windstorms over Europe. As well as storm frequencies and peak wind speeds, we also quantify changes in two versions of a storm severity index (SSI), one of which is population weighted. These metrics are calculated using the footprints of cyclones as they pass over the European continent.

The models show differing abilities to represent the historical SSI compared to ERA5. Future changes in SSI are somewhat uncertain, but tend to show an increase in severities over central and northwest Europe, and a decrease over lower latitudes and the Mediterranean, with responses tending to be larger for the more extreme climate change scenario. These changes are associated with the changes in the extreme winds over land.

By considering the parameters of population density and wind intensity threshold we could explore the relevance of future socio-economic and adaptive changes on the windstorm impacts. For the population-weighted SSI, smaller increases are found in the future cases where population densities do not change and/or adaptation to increases in extreme wind speed climatologies occur.
Locating flowing conduits in Karst using passive seismic deployments
Authors: Karbala Ali Haleh , Bean Christopher J. , Hickey Caoimhe , o'Keeffe Billy
Published: March 2021

Karst is an important landscape in many locations incorporating many subterranean waterflow passages in the form of caves, conduits, and fractures. Although challenging, some karst structures can be imaged by active geophysical techniques however they generally cannot facilitate differentiation between flowing and non-flowing waterways. In this study, we aim to locate flowing conduits by passively capturing flow-induced seismic signals.

To gain a broad understanding of seismic source versus path effect in these complex structures and to help us design bespoke field experiments, we commence our study by undertaking 3D numerical simulation (using SPECFEM3D) for different cases of shallow and deep conduits. These choices are informed by known conduit geometries in Ireland (they have been dived). Spectral resonance, synthetic heat maps, and amplitude-based locations of synthetic data reveal interesting information regarding the conduit response.

Based on the results of these simulations, we designed the layout of a passive field experiment on karst on Pollnagran cave in County Roscommon, Ireland using 1Hz seismometers and 5 Hz Geophones. The karst deployment is also complemented by smaller experiments on surface rivers in order to help better understand observed signals. We also undertake an active hammer seismic survey at the site in order the build a model for future site-specific numerical simulations.

Consistent with numerical experiments, clear discrete frequencies associated with water flow are observed in the field data. A complex picture is emerging where the largest dived caves are not necessarily the flow structures with the largest seismic amplitudes.
High-resolution 3D Forecasting System for Barcelona's beaches and coastal waters
Authors: Liste Muñoz María , Mestres Ridge Marc , Espino Infantes Manuel , Sánchez-Arcilla Agustín , García León Manuel , García Sotillo Marcos , Álvarez Fanjul Enrique
Published: March 2021

The ocean is an essential part of the planet that plays a crucial role in the global life system and provides vital resources for humanity. Coastal areas are the most affected by direct pressure from human activity, and their management is very complex due to the multiple interconnected processes that occur there. To conserve and protect our coastal areas, we must observe and understand how they interact. Despite its paramount importance to society, there are fundamental gaps in coastal observing and modelling. Therefore, current forecasting systems limit our capacity to manage this narrow border between land and sea sustainably. Improved numerical models and sustained observations of our ocean are needed to make informed decisions and ensure that human-coastal interaction is sustainable and safe.

EuroSea initiative is an innovation action of the European Union entitled "Improvement and integration of the European oceans Observation and prediction systems for the sustainable use of the oceans'. EuroSea brings together the leading European players in the ocean observation and forecasting with users of oceanographic products and services and provides high-resolution coastal operational prediction systems in domains such as ports, beaches and nearby coastal waters.

In the EuroSea project framework, we present a 3D hydrodynamic tool to improve Barcelona's beaches' inner dynamics solution. We use the Coupled Ocean-Atmosphere - Wave - Sediment Transport (COAWST) Modeling System that utilizes the Model Coupling Toolkit to exchange prognostic variables between the ocean model ROMS, wave model SWAN, and the Community Sediment Transport Modeling System (CSTMS) sediment routines. As part of the system, the wave and ocean models run with nested, refined, spatial grids to provide increased resolution, scaling down to resolve nearshore wave-driven flows, all within selected regions of a larger, coarser-scale coastal modelling system.

Bathymetry was built using a combination of bathymetric data from EMODnet (European Marine Observation and Data Network), and specific high-resolution sources provided by local authorities. Copernicus products have driven these high-resolution simulations.

Results have been validated with field campaigns data, displaying preliminary agreements between model outputs and in-situ observations. The model provides results that will be used to study interactions between sea-level hazards, economic activity, and risk. These results will develop new forecast capabilities, such as erosion and flooding, rip currents, floating debris and flushing times.

Finally, we look ahead to the future of the operational prediction systems as useful tools to make informed decisions, minimize risks and improve environmental management.
High-resolution radiocarbon dating to reconstruct last century environmental changes in the pacific island of Espiritu Santo
Authors: Camperio Giorgia , Welte Caroline , Ladd S. Nemiah , Prebble Matthew , Dubois Nathalie
Published: March 2021

Espiritu Santo is one of the 82 islands of the archipelago of Vanuatu and is the largest, highest, and most biodiverse of the insular country. Climatic changes linked to El Niño and extreme events such as cyclones and volcanic eruptions are a daily challenge in this remote area. These events can be recorded in sedimentary archives. Here we present a multi-proxy investigation of sediment cores retrieved from two small lakes located on the West coast of Espiritu Santo. Although the records span the last millennium, high-resolution radiocarbon dating of macrofossils reveals a rapid accumulation of sediment in the past 100 years. The high accumulation rate coupled with the high-resolution dating of freshwater sediments allows us to compare the 14C bomb curve with the biogeochemical proxies of the sedimentary records. The results can then be validated against written and oral historical records linked with the societal perception of recent environmental changes in this vulnerable ecosystem.
Evaluating performances of one-year simulation by using 3.5 km mesh global nonhydrostatic model
Authors: Yamada Yohei , Kodama Chihiro , Noda Akira , Satoh Masaki , Nakano Masuo , Miyakawa Tomoki , Yashiro Hisashi , Nasuno Tomoe
Published: March 2021

Recent advancement of supercomputing enables us to conduct a climate simulation by using a global model with horizontal grid spacing of a few kilometers. We may need to tune the model in order to conduct a reliable simulation. In order to test feasibility of a few kilometer climate simulation in near future, we conducted one-year simulation from June 2004 to May 2005 by using Nonhydrostatic Icosahedral Atmospheric Model (NICAM) with horizontal grid spacing of 28 km, 14 km, 7 km, and 3.5 km, and evaluated their simulation performances. In general, global models have shown weak wind speed of tropical cyclones compared to its central sea level pressure due to insufficient horizontal resolution. As expected, the 3.5 km simulation showed improvement of this bias. As for simulated mean state, globally annual mean precipitation tended to be decreased with finer horizontal resolution in NICAM. Compared with observation (Global Precipitation Climatology Project V2.2; 2.71 mm day-1), 7 km and 3.5 km simulations underestimated the global mean precipitation (2.54 mm day-1 and 2.67 mm day-1), while 14 km and 28 km simulations overestimated (2.84 mm day-1 and 2.78 mm day-1). The 3.5 km simulation showed the best performance for reproducing globally annual mean precipitation. However, the 3.5 simulation showed underestimation of the South Pacific Convergence Zone. In order to conduct a reliable simulation, we need to improve performance of the 3.5 km global model. This demands extensive computing resources. The supercomputer Fugaku will give us extensive computing resources for addressing this issue.
Climatology of moisture sources fuelling extreme precipitation in the Western Mediterranean region
Authors: Insua Costa Damián , Miguez-Macho Gonzalo , Llasat María Carmen
Published: March 2021

The Western Mediterranean region (WMR) is usually affected by heavy rainfall, which has been extensively studied in the past because of the enormous impact it causes. However, there is still an open question related to these potentially catastrophic episodes: does the water vapour that feeds precipitation actually come from the Mediterranean Sea? Several studies have pointed to a significant contribution from other moisture sources, but the debate remains open because only a few case studies with disparate findings have been analysed so far. Here we use the Weather Research and Forecasting (WRF) model with a coupled moisture tagging capability to simulate over one hundred cases of extreme precipitation in the WMR. In order to detect possible remote moisture sources, we use a domain that covers almost the entire northern hemisphere. Preliminary results show that, although the contribution from the Mediterranean Sea is crucial, the combined contribution from more distant sources in the tropical, subtropical and north Atlantic is higher on average. In some specific cases, a significant part of the humidity may come from sources as far away as the Pacific Ocean. Our findings suggest that when explaining WMR torrential rainfall episodes, the Mediterranean Sea should be generally understood as a precipitation enhancer rather than the main contributor to precipitation.
Global Continental Residual Topography
Authors: Stephenson Simon , Hoggard Mark , White Nicky
Published: March 2021

Convective circulation in the mantle supports some fraction of Earth’s topography. It is challenging to observe this topographic expression of mantle convection because it is contaminated by crustal and lithospheric isostatic processes. In the oceanic realm, residual bathymetry has been calculated by removing the effects of sedimentary and crustal thickness variations and comparing to the well-known plate cooling trend, revealing sub-plate topographic support that is up to 1–2 km in amplitude and varies on wavelengths of ~1000 km. On the continents, crustal thickness and density variations support a much larger fraction of topography. Similarly, the density and thickness of the lithospheric mantle do not follow a simple predictive relationship. It is therefore significantly more challenging to calculate the component of sub-plate topographic support in the continental realm. Here, we assemble a database of > 20,000 continental crustal thickness estimates from published active and passive source seismic experiments with a goal of exploring the topographic expression of crustal, lithospheric, and sub-plate mantle structure. A subset of these studies provides constraints on crustal seismic velocity structure which can be used to estimate local density structure of the continental crust. We exploit a database of laboratory-determined density and velocity measurements of crustal rocks to develop a velocity to density conversion scheme. We use these constraints on crustal structure to remove the effects of crustal thickness and density variations and calculate an estimate of residual topography that arises from mantle processes. We compare these values of residual topography to an independent, tomographically derived map of lithospheric thickness. We find that residual topography is negatively correlated with lithospheric mantle thickness, which is expected and consistent with oceanic lithospheric observations. Next, we exploit a pressure and temperature-dependent density parametrisation to calculate and remove the expected topographic contribution of the lithospheric mantle. This approach demonstrates that up to 3 km of residual topography is positively correlated with lithospheric thickness even after removing the effects of cooling and thickening of the plate, indicating that compositional factors may lead to decreasing density with increasing lithospheric thickness. This relationship is in broad agreement with constraints on lithospheric mantle composition from xenoliths. Our analysis demonstrates the importance of accounting for lithospheric structure in the continental realm in constraining the sub-plate, dynamic contribution to Earth’s topography. An important corollary is that changes to the density and thickness of lithospheric mantle drive rapid vertical motions of the Earth’s surface which are increasingly recognised as causes of regional epeirogenic uplift.
The Europlanet Evaluation Toolkit
Authors: Heward Anita , DeWitt Jen
Published: March 2021

In this presentation, we will give an overview of the Europlanet Evaluation Toolkit, a resource that aims to empower outreach providers and educators in measuring and appraising the impact of their activities. The toolkit is intended to provide advice and resources that can be simply and easily integrated into normal outreach and education activities. It is available as an interactive online resource (http://www.europlanet-eu.org/europlanet-evaluation-toolkit/), as a downloadable PDF and as a hard copy (including a book and set of activity cards).

The toolkit has been developed over a number of years with content provided by professional outreach evaluators Karen Bultitude and Jennifer DeWitt (UCL, UK). Initially, a series of focus groups and scoping discussions were held with active outreach providers from the planetary science community in order to determine what they wanted from such a toolkit, and what sort of tools would be of most interest. A shortlist of tools was developed based on these discussions, with volunteers testing out the tool instructions once they were drafted.

The toolkit begins with a brief introduction to evaluation and steps to choosing the right tools. This advice takes the form of a series of questions to help design an evaluation approach and make the most efficient and effective use possible of limited time and resources.

The toolkit offers a choice of 14 data collection tools that can be selected according to the audience (e.g. primary, secondary, interested adult, general public), the type of environment and activity (e.g. drop-in, interactive workshop, ongoing series, lecture/presentation or online) or according to when they might best be used (during, beginning/end, or after an event). The online version of the toolkit includes a set of interactive tables to help with the selection of which tool is most appropriate for any given situation.

The toolkit includes descriptions and worked examples of how to use two techniques (word-clouds and thematic coding) to analyse the data, as well as some top tips for evaluation and recommended resources.

For some of the tools, case study examples include information about how the tools have been used in the context of an event, how data was actually collected and analysed and what conclusions were reached, based on the data gathered.

The Europlanet Evaluation Toolkit has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 871149 (Europlanet 2024 RI) and 654208 (Europlanet 2020 RI).
REY contents in Fe-Mn crusts in Macaronesia: evidence of variation with depth and mineralogy
Authors: Marino Egidio , González Francisco Javier , Medialdea Teresa , Somoza Luis , Ferreira Pedro , Kuhn Thomas , Magalhaes Vitor , Lobato Ana
Published: March 2021

Bulk mineralogy and geochemistry data of Fe-Mn crusts from seamounts of the Macaronesia region (Canary Islands and Madeira and Azores archipelagos) compiled for the MINDeSEA Database, have been analyzed using statistical tools and related with their location and sampling depth.
Results show that the predominant mineralogy is represented by hydrogenetic Fe-vernadite and goethite, with minor abundance of other Mn-oxides such as buserite, asbolane and todorokite in crusts influenced by early diagenesis. Bulk geochemistry is dominated by Fe and Mn (ranging from 7 to 29 wt. %) with low aluminum-silicate elements (10 wt. % in average) and with significant average contents of several strategic and critical metals like Co, Ni, V, Mo, Te and especially REYs (4700, 2300, 1000, 400, 50 and 2500 µg/g respectively).
Variation of REYs and energy critical element (Co, Mn and Te) contents as a function of water depth and mineralogy are clearly evident in this study. Geochemical and statistical studies (Pearson correlation and factorial analysis with Varimax) reveal that Fe-Mn crusts recovered at water depths just below the oxygen minimum zone (that in this area is located between 300 and 1000 m) at Tropic, Tore, Unicorn and Bimbache seamounts, show an enrichment of all REYs and especially LREEs (Ce is the most enriched element with up to 2900 µg/g). On the other hand, the crusts recollected from the deepest seamounts: Drago, Gaire and MTR (up to 4900 m water depth) show a slightly depletion in all the REYs, especially La and Ce (300 and 1800 µg/g in average respectively). A similar behavior can also be observed for the other energy critical elements where enrichment or depletion is clearly linked to water depth. Additionally, there is a correlation of REY abundance with the mineralogy.  High-resolution studies show that REY are concentrated up to an order of magnitude lower in the diagenetic Mn oxide minerals than in the hydrogenetic phases, possibly due to their high growth rates that don’t allow the concentration of these elements. This work is part of the investigation related to the metallogenetic models for marine minerals developed in the Geo-ERA MINDeSEA1 European project.

[1] This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 731166
Identifying meteorological drivers of extreme impacts: an application to simulated crop yields
Authors: Zscheischler Jakob , Vogel Johannes , Rivoire Pauline , Deidda Cristina , Rahimi Leila , Sauter Christoph , Tschumi Elisabeth , van der Wiel Karin , Zhang Tianyi
Published: March 2021

Compound weather events may lead to extreme impacts that can affect many aspects of society including agriculture. Identifying the underlying mechanisms that cause extreme impacts, such as crop failure, is of crucial importance to improve their understanding and forecasting. In this study we investigate whether key meteorological drivers of extreme impacts can be identified using Least Absolute Shrinkage and Selection Operator (Lasso) in a model environment, a method that allows for automated variable selection and is able to handle collinearity between variables. As an example of an extreme impact, we investigate crop failure using annual wheat yield as simulated by the APSIM crop model driven by 1600 years of daily weather data from a global climate model (EC-Earth) under present-day conditions for the Northern Hemisphere. We then apply Lasso logistic regression to determine which weather conditions during the growing season lead to crop failure.

We obtain good model performance in Central Europe and the eastern half of the United States, while crop failure years in regions in Asia and the western half of the United States are less accurately predicted. Model performance correlates strongly with annual mean and variability of crop yields, that is, model performance is highest in regions with relatively large annual crop yield mean and variability. Overall, for nearly all grid points the inclusion of temperature, precipitation and vapour pressure deficit is key to predict crop failure. In addition, meteorological predictors during all seasons are required for a good prediction. These results illustrate the omnipresence of compounding effects of both meteorological drivers and different periods of the growing season for creating crop failure events. Especially vapour pressure deficit and climate extreme indicators such as diurnal temperature range and the number of frost days are selected by the statistical model as relevant predictors for crop failure at most grid points, underlining their overarching relevance.

We conclude that the Lasso regression model is a useful tool to automatically detect compound drivers of extreme impacts, and could be applied to other weather impacts such as wildfires or floods. As the detected relationships are of purely correlative nature, more detailed analyses are required to establish the causal structure between drivers and impacts.
Mutual relations between tress drop of induced earthquakes and fault cohesion.
Authors: Shapiro Serge
Published: March 2021

In some regions a significant stress drop characterizes earthquakes induced by underground fluid injections or productions. In addition, long-term fluid operations in the underground can influence a seismogenic reaction of the rock per unit volume of the fluid involved. The seismogenic index is a quantitative characteristic of such a reaction. We derive a relationship between the seismogenic index and the stress drop. We propose a simple and rather general phenomenological model of the stress drop of induced earthquakes. Our model suggests that a high stress drop can result from a decrease in cohesion of initially inactive faults that are seismically activated by long-term fluid operations. On the one hand, the increasing stress drop can lead to an increase in the seismogenic index with the time of fluid operations. On the other hand, a production/injection caused change of the pore pressure can also cause a systematic increase in the stress drop. This can provide an additional contribution to the growth of seismogenic index (and thus to the seismic risk) with operation time of reservoirs.

The case study of Groningen gas field provides interesting information in this respect. A significant stress drop of some induced earthquakes at Groningen can be explained by activating preexisting cohesive normally-stressed fault systems. Seismic events on such faults lead to the drop of their cohesion due to the rupture process. This cohesion drop contributes directly to the earthquake stress drop. The production-related increase of the differential stress in the reservoir leads to an increasing number of seismically activated more cohesive faults. This leads in turn to an increasing seismogenic index. The seismogenic index seems to be quite low at Groningen. However, it increases systematically with the production time. One of reasons of this behavior can be related to the average cohesion of involved faults as it is mentioned above. An additional effect contributing to this increase is a systematically increasing stress drop due to the production-related pressure depletion increasing the effective stress in the reservoir. A growing seismogenic index can result in an increasing with time maximum possible magnitude, Mmax.
Upwelling signature around small oceanic islands and the case of the Maldives Archipelago
Authors: De Falco Chiara , Bracco Annalisa , Pasquero Claudia
Published: March 2021

Around the Maldives, it was found that the interaction between currents and the steep bathymetry is responsible for a local cooling of about 0.2°C in the Archipelago during the warmest season, with respect to the surrounding waters. The reduced SST is probably linked to the Island Mass Effect: the enhanced productivity around small islands discovered in the sixties and documented worldwide. Despite its effects on marine productivity, the exact description of the physical processes behind the local cooling and nutrient input that enhances productivity is still unclear. From the analysis of SST variations and net primary productivity (NPP) around small islands and archipelagos, two kinds of signals can be identified, depending on the altitude and dimension of the islands. Around islands with considerable elevation and greatest diameters, cold/warm anomalies, most likely corresponding to upwelling/downwelling zones, emerge. Warmer areas don’t appear around smaller islands that usually display only a local cooling. Several oceanic and atmospheric processes might be involved. The case of the Maldives has been analyzed in detail using CROCO and a particle tracking model: Ariane. More than one process might coexist in generating the described patterns, the prevailing one varying along the year and depending on the strength and direction of the incoming flow. Near the Maldives, the frictional break of the currents in the presence of shallow bathymetry produces a strong vertical shear in the flow that favors vertical mixing and produces a nearly symmetric cooling around the islands. A different mechanism dominates the cooling pattern when the currents are particularly intense, such as during the monsoons: intense zonal currents cross the Archipelago and give rise to intense wakes with large horizontal shear; strong upwelling originates in the lees, creating an asymmetric temperature signal (larger cooling in the lee of the islands) and obfuscating the effects of the enhanced vertical mixing.
Geochemical transformation of forested catchments following bark beetle infestation: Evidence from EC hysteresis during rainfall-runoff events
Authors: Su Ye , Langhammer Jakub
Published: March 2021

Forest disturbance resulting from bark beetle infestation is becoming a widespread phenomenon due to climate warming and changing precipitation patterns. Such disturbance could result in alterations of streamflow and stream geochemistry. Our previous study found that these changes developed relatively rapidly after infestation and have long-lasting (decadal-scale) effects. Furthermore, infestation-induced changes in event-scale dynamics of in-stream electric conductivity (EC) – discharge (Q) relations were found to be considerable, impacting even the annual average EC-values. In this study, therefore, all rainfall-induced runoff events occurring during an 11-year period were identified and their distinct EC-Q relations were evaluated. The evaluation was done based on 10-min high-frequency monitoring of Q and EC and in four experimental catchments (~4 km2 each; located in the Sumava Mountains, Central Europe), having different forest cover (disturbance) stages. Furthermore, snapshot sampling was carried out to map EC and chemical parameters (N, DOC, etc.) in different hydrological landscape units (riparian area, hillslope, and terrace) and in multiple vertical layers of soil (surface, soil, and groundwater). Results showed that after infestation the EC-Q hysteresis loops at the event-scale shifted from positive to negative relationships, implying changes in the subsurface chemical composition and runoff patterns. Specifically, healthy forest systems required event flows to mobilize substances in the soil and groundwater systems as the groundwater level rose into the relatively conductive, shallow part of the soil profile during an event. Such flush-driven systems were known for their release of large fractions of total annual in-stream substance loads showing a positive EC-Q relationship. By contrast, after infestation-induced tree mortality, the mobilization and downward percolation of nutrients and carbon from litter and decomposing needles may be considerable even during moderate rain and infiltration events. When the system is flooded under event conditions, substance-enriched soil water and groundwater may be mixed with and diluted by low-salinity event water, leading to a negative EC-Q relationship.  This study exemplifies how EC monitoring techniques can be used as an alternative to high-cost geochemical monitoring in quantifying complex rainfall-runoff processes as well as runoff generation processes, allowing for long monitoring periods at high temporal resolution and reasonable costs.
Showcasing the compact Earth system model OSCAR v3.1 with CMIP6 simulations
Authors: Quilcaille Yann , Gasser Thomas
Published: March 2021

While Earth system models (ESM) provide spatially detailed process-based outputs, they present heavy computational costs. Reduced complexity models such as OSCAR are calibrated on those complex models and provide an alternative with faster calculations but lower resolutions. Yet, reduced-complexity models need to be evaluated and validated. We diagnose the newest version of OSCAR (v3.1) using observations and results from ESMs and the current Coupled Model Intercomparison Project 6. A total of 99 experiments are selected for simulation with OSCAR v3.1 in a probabilistic framework, reaching a total of 567,700,000 simulated years. Here, we showcase these results. A first highlight of this exercise is the unstability of the model for high-warming scenarios, which we attribute to the ocean carbon cycle module. The diverging runs caused by this unstability were discarded in the post-processing. The ensuing main results were further obtained by weighting each physical parametrizations based on their performance to replicate a set of observations. Overall, OSCAR v3.1 qualitively behaves like complex ESMs, for all aspects of the Earth system, although we observe a number of quantitative differences with state-of-the-art models. Some specific features of OSCAR contribute in these differences, such as its fully interactive atmospheric chemistry and endogenous calculations of biomass burning, wetlands and permafrost emissions. Nevertheless, the low sensitivity of the land carbon cycle to climate change, the unstability of the ocean carbon cycle, the seemingly over-constrained climate module, and the strong climate feedback over short-lived species, all call for an improvement of these aspects in OSCAR. Beyond providing a key diagnosis of the model in the context of the reduced-complexity models intercomparison project (RCMIP), this work is also meant to help with the upcoming calibration of OSCAR on CMIP6 results, and to provide a large set of CMIP6 simulations all run consistently with a probalistic model.
Minimising the computational time of a waveform based location algorithm
Authors: Parastatidis Emmanouil , Pytharouli Stella , Stankovic Lina , Stankovic Vladimir , Shi Peidong
Published: March 2021

Accurate and fast localisation of microseismic events is a requirement for a number of applications, e.g. mining, enhanced geothermal systems. New methods for event localisation have been proposed over the last decades. The waveform-based methods are of the most recent developed ones and their main advantage is the ability to locate weak seismic events. Despite this, these methods are demanding in terms of computational time, making real-time seismic event localisation very difficult. In this work, we further develop a waveform-based method, the Multichannel coherency migration method (MCM), to improve the computational time. The computational time for the MCM algorithm has been reported to linearly depend on several parameters, such as the number of stations, the length of the waveform time window, the computer architecture, and the volume of the area we are searching for the hypocentre. To minimise the computational time we need to decrease one or more of the above parameters without compromising the accuracy of the result. We break the localisation procedure into several steps: (1) we locate the event with a relatively large spatial grid interval which will give less potential hypocentral locations and less calculations as a result. (2) Based on the results of step (1) and the locations of maximum coherencies we decrease the grid volume to a quarter of the original volume and the spatial interval to half the original, focusing only around the area identified in step (1). Step (2) is repeated several times for decreased grid volumes and spatial intervals until the hypocentral location does not significantly change any more. We tested this approach on both synthetic and real data. We find that while the accuracy of the hypocentre is not compromised, the computational time is up to  125,000 times shorter.    
Crustal Structure across Central Scandinavian Peninsula along Silver Road refraction profile
Authors: Kahraman Metin , Thybo Hans , Artemieva Irina , Shulgin Alexey , Malehmir Alireza , Mjelde Rolf
Published: March 2021

The Baltic Shield is located in the northern part of Europe, which formed by amalgamation of a series of terranes and microcontinents during the Archean to the Paleoproterozoic, followed by significant modification in Neoproterozoic to Paleozoic time. The Baltic Shield includes an up-to 2500 m high mountain range, the Scandes , along the western North Atlantic coast, despite being a stable craton located far from any active plate boundary.

We study a crustal scale seismic profile experiment in northern Scandinavia between 63oN and 71oN. Our Silverroad seismic profile extends perpendicular to the coastline around Lofoten and extends ~300km in a northwest direction across the shelf into the Atlantic Ocean and ~300km in a southeastern direction across the Baltic Shield. The seismic data were acquired with 5 explosive sources and 270 receivers onshore; 16 ocean bottom seismometers and air gun shooting from the vessel Hakon Mosby were used to collect both offshore and onshore.

We present the results from raytracing modelling of the seismic velocity structure along the profile. The outputs of this experiment will help to solve high onshore topography and anomalous and heterogeneous bathymetry of the continental lithosphere around the North Atlantic Ocean. The results show crustal thinning from the shield onto the continental shelf and further into the oceanic part. Of particular interest is the velocity below the high topography of the Scandes, which will be discussed in relation to isostatic equilibrium along the profile.