bluuebunny/crossref_metadata_2025 huggingface dataset:
The MULTI OBSERVATIONS Thematic Assembly Centre of the Copernicus Marine Environment Monitoring Service
Authors: Guinehut Stephanie , Buongiorno Nardelli Bruno , Chau Trang , Chevallier Frederic , Ciani Daniele , Claustre Herve , Etienne Helene , Gehlen Marion , Greiner Eric , Jousset Solene , Mulet Sandrine , Sauzède Raphaelle , Verbrugge Nathalie
Published: March 2021

Complementary to ocean state estimate provided by modelling/assimilation systems, a multi observations-based approach is available through the MULTI OSERVATIONS (MULTIOBS) Thematic Assembly Center (TAC) of the European Copernicus Marine Environment Monitoring Service (CMEMS).

CMEMS MULTIOBS TAC proposes products based on satellite & in situ observations and state-of-the-art data fusion techniques. These products are fully qualified and documented and, are distributed through the CMEMS catalogue (http://marine.copernicus.eu/services-portfolio). They cover the global ocean for physical and biogeochemical (BGC) variables. They are available in Near-Real-Time (NRT) or as Multi-Year Products (MYP) for the past 28 to 36 years.

Satellite input observations include altimetry but also sea surface temperature, sea surface salinity as well as ocean color. In situ observations of physical and BGC variables are from autonomous platform such as Argo, moorings and ship-based measurements. Data fusion techniques are based on multiple linear regression method, multidimensional optimal interpolation method or neural networks.

MULTIOBS TAC provides the following products at global scale:

3D temperature, salinity and geostrophic current fields, both in NRT and as MYP;

2D sea surface salinity and sea surface density fields, both in NRT and as MYP;

2D total surface and near-surface currents, both in NRT and as MYP;

3D vertical current as MYP;

2D surface carbon fields of CO2 flux (fgCO2), pCO2 and pH as MYP;

Nutrient vertical distribution (including nitrate, phosphate and silicate) profiles as MYP;

3D Particulate Organic Carbon (POC) and Chlorophyll-a (Chl-a) fields as MYP.

Furthermore, MULTIOBS TAC provides specific Ocean Monitoring Indicators (OMIs), based on the above products, to monitor the global ocean 3D hydrographic variability patterns (water masses) and the global ocean carbon sink.
Regional-scale analysis of dune-beach systems using Google Earth Engine
Authors: Latella Melissa , Luijendijk Arjen , Camporeale Carlo
Published: March 2021

Coastal sand dunes provide a large variety of ecosystem services, among which the inland protection from marine floods. Nowadays, this protection is fundamental, and its importance will further increase in the future due to the rise of the sea level and storm violence induced by climate change. Despite the crucial role of coastal dunes and their potential application in mitigation strategies, the phenomenon of the coastal squeeze, which is mainly caused by the urban sprawl, is progressively reducing the extents of the areas where dune can freely undergo their dynamics, thus dramatically impairing their capability of providing ecosystem services.

Aiming to embed the use of satellite images in the study of coastal foredune and beach dynamics, we developed a classification algorithm that uses the satellite images and server-side functions of Google Earth Engine (GEE). The algorithm runs on the GEE Python API and allows the user to retrieve all the available images for the study site and the chosen time period from the selected sensor collection. The algorithm also filters the cloudy and saturated pixels and creates a percentile-composite image over which it applies a random forest classification algorithm. The classification is finally refined by defining a mask for land pixels only. 

According to the provided training data and sensor selection, the algorithm can give different outcomes, ranging from sand and vegetation maps, beach width measurements, and shoreline time evolution visualization. This very versatile tool that can be used in a great variety of applications within the monitoring and understanding of the dune-beach systems and associated coastal ecosystem services. For instance, we show how this algorithm, combined with machine learning techniques and the assimilation of real data, can support the calibration of a coastal model that gives the natural extent of the beach width and that can be, therefore, used to plan restoration activities. 
Forty years record of the metalimnetic oxygen minimum in Germany’s largest drinking water reservoir
Authors: Seewald Michael , Mi Chenxi , Donner Jan , Rinke Karsten
Published: March 2021

Dissolved oxygen is a central player in water quality management of lakes and reservoirs. Low levels or absence of oxygen poses a major problem, especially in drinking water reservoirs. Usually, the focus lies on the oxygen depletion in deep water. However, in many stably stratified water bodies, significant oxygen deficits have been documented in the metalimnion, even in lakes of low trophic state. This phenomenon is known as metalimnetic oxygen minimum (MOM) and the causes of MOM have been discussed controversially. The Rappbode Dam, Germany's largest drinking water reservoir, forms a MOM every year and long-term observations indicate that the oxygen deficit may have increased in recent years. Although the data cover a long period (40 years), they are very heterogeneous in terms of temporal and spatial resolution. Our study aims at systematically analysing the available data to characterize the interannual development of the MOM with respect to existing trends and to identify relevant environmental and management factors. The results confirm increasing surfacewater temperatures and unchanged deepwater temperatures in summer (Mai to October) as well as an increasingly prolonged summer stratification in the course of global warming. In contrast to the previous working hypothesis, increasing stratification duration is not correlated with the significantly increasing (p 0.009; τ -0.26) annual maximum intensity of the MOM.
The science system on-board the Emirates Lunar Mission's Rashid rover
Authors: Els Sebastian , Almaeeini Sara , Almarzooqi Hamad
Published: March 2021

The Emirates Lunar Mission is developing the small and light weight "Rashid" rover. The goals for this rover are to traverse several hundred meters on the lunar surface during the course of one lunar day. The Rashid rover's science objectives cover both fundamental science as well as engineering topics with the goal to enable future missions to the lunar surface, and other airless solar system bodies. Hence, Rashid will carry a suite of scientific instruments and an experiment, covering a wide range of the physical properties at the lunar surface. The focus of investigation for the microscopic imager (CAM-M) will be to measure the regolith particle size distribution, and the lunar surface structure at microscopic scales. The Langmuir probe system (LNG) will address  the  electron density profile of the sheath, its behavior over the course of the lunar day, and its dependence on topographic features.  A thermal imager (CAM-T) with low spatial resolution is also foreseen. Finally, the in-situ testing of the adhesive and abrasive properties of various materials to lunar regolith is planned to be conducted by the MAD experiment.  In this paper the science program and instrumentation of the Rashid mission will be outlined.
Introducing the Vienna Urban Carbon Laboratory (VUCL)
Authors: Matthews Bradley , Watzinger Andrea , Chen Jia , Schume Helmut , Sanden Hans , Dietrich Florian , Leitner Simon
Published: March 2021

The Vienna Urban Carbon Laboratory (VUCL) has begun testing in situ measurement-based options for monitoring local carbon dioxide (CO2) and methane (CH4) emissions in Austria’s capital city. Building upon the groundwork of the CarboWien project, VUCL extends and expands the current tall-tower eddy covariance flux system and will furthermore conduct campaigns to measure carbon isotopes and isofluxes, as well as upwind-downwind gradients in total column CO2 and CH4 mixing ratios. The project, which runs between 2021 and 2024 and is funded by the Vienna Science and Technology Fund (WWTF), will be implemented by a collaboration between the University of Natural Resources and Life Sciences Vienna (BOKU), the Technical University of Munich (TUM), the Environment Agency Austria (EAA) and A1 Telekom Austria AG (A1). In addition to contributing to international research into measurement-based greenhouse gas emissions monitoring, the multi-method approach provides an opportunity to demonstrate measurement-based emissions monitoring options directly to Vienna’s civil servants responsible for climate change mitigation action in the city. Continuous local stakeholder engagement over the project duration is therefore planned.

This conference contribution to the WMO-IG3IS session at vEGU21 will allow VUCL to be introduced to relevant scientists and stakeholders in the international community. Given the recent project start (01 Feb 2021), the foreseen discussions on the project’s planned implementation will provide an important and timely input into VUCL. Finally, initial VUCL results will be presented together with data from the preceding CarboWien project (2018-2020) to show how the measured CO2 fluxes in Vienna have been impacted by the lockdown restrictions due to the COVID-19 pandemic.
An Exhumation Pulse From the Nascent Franciscan Subduction Zone (California, USA)
Authors: Rutte Daniel , Garber Joshua , Kylander-Clark Andrew , Renne Paul
Published: March 2021

We investigated a suite of metabasite blocks from serpentinite matrix and shale matrix mélanges of the California Coast Ranges. Our new data set consists of 40Ar/39Ar dates of amphibole and phengite and U‐Pb dates of metamorphic zircon. Combined with published geochronology, including prograde Lu‐Hf garnet ages from the same blocks, we can reconstruct the timing and time scales of prograde and retrograde metamorphism of individual blocks. In particular we find that exhumation from amphibole‐eclogite facies conditions occurred as a single episode at 165–157 Ma, with an apparent southward younging trend. The rate and timing of exhumation were initially uniform (when comparing individual blocks) and fast (with cooling rates up to ~140°C/Ma). In the cooler and shallower blueschist facies, exhumation slowed and became less uniform among blocks. Considering the subduction zone system, the high‐grade exhumation temporally correlates with a magmatic arc pulse (Sierra Nevada) and the termination of forearc spreading (Coast Range Ophiolite). Our findings suggest that a geodynamic one‐time event led to exhumation of amphibole‐eclogite facies rocks. We propose that interaction of the Franciscan subduction zone with a spreading ridge led to extraction of the forearc mantle wedge from its position between forearc crust and subducting crust. The extraction led to fast and uniform exhumation of subducted rocks into the blueschist facies. We also show that the Franciscan subduction zone did not undergo significant cooling over time and that its initiation was not coeval with blueschist‐facies metamorphism of the Red Ant schist of the Sierra Nevada foothills.
Inventory and preliminary assessment of natural hazards in Kigezi highlands, South Western Uganda
Authors: Kanyiginya Violet , Twongyirwe Ronald , Kagoro Grace , Mubiru David , Kervyn Matthieu , Dewitte Olivier
Published: March 2021

Uganda is regularly affected by multiple natural hazards, including floods, droughts, earthquakes, landslides and windstorms. This is due to a combination of natural biophysical factors such as steep topography, intense rainfall, variability of dry and rain seasons and high weathering rates. In addition, high population density, deforestation and other human-induced land use changes, and high poverty levels are believed to have an influence on the patterns of natural hazards and their impacts in the region. Despite this, there are limited studies that assess where and when natural hazards occur in Uganda, and a dearth of information on the processes involved. In addition, drivers and earth/landscape characteristics controlling the occurrence of natural hazards in the country remain poorly understood despite the high need for effective disaster risk reduction. Here, we present the ongoing methodological research framework and the first results of a study whose main objective is to understand the spatial and temporal occurrence of natural hazards that affect the Kigezi Highlands of south western Uganda and their interactions. To this end, the study is undertaking a comprehensive regional hazard inventory consisting of satellite image analysis, field surveys and exploration of literature and archives. Historical aerial photos and interviews with the elderly are important tools to analyze the impact of multi-decadal human-induced land use changes on natural hazard occurrences. Meanwhile, a network of 15 geo-observers, i.e. citizens of local communities distributed across representative landscapes of the study area, was established in December 2019. Trained at using smartphone technology, they collect information (processes and impacts) on seven different natural hazards (droughts, earthquakes, floods, hailstorms, landslides, lightning, and windstorms) whenever they occur.  During the first 12 months, 204 natural hazard events with accurate timing information have been reported by the geo-observers. Combined to field survey, these recent events have been associated mainly with the occurrence of > 3000 shallow landslides and 30 floods, frequently in co-occurrence and triggered by heavy rainfall. Additional inventory from Google Earth and Planet imagery covering a region much larger than that of the geo-observer network and a time window of more than 10 years shows an extra 230 landslide and flood occurrences, while archives and literature indicate 226 natural hazard events over the last 30 years. The preliminary results already demonstrate the value of citizen-science in producing highly detailed natural hazard inventory. A combination of different inventory methods improves the level of accuracy in understanding the spatial-temporal distribution of natural hazards.
Coupled processes in an ocean-sea ice-wave configuration
Authors: Rynders Stefanie , Aksenov Yevgeny , Coward Andrew
Published: March 2021

Marginal ice zones are areas with many interactions between ocean, surface waves, sea ice and atmosphere. Increasing computational power makes it possible to perform increasingly complex simulations of marine systems, with more components of the climate system that are more interacting. We have produced a set of increasingly coupled simulations with NEMO, CICE and WW3, exchanging more and more variables. The configuration is global at 1 degree resolution. The focus is on wave attenuation in sea ice and the impact of using modelled wave height for ocean mixing due to breaking waves. The example simulations give an idea of the possible impact on the simulated state versus the still considerable computational cost.
Analyzing the performance of a rain garden over 15 years 
Authors: Amur Achira , Wadzuk Bridget , Traver Robert
Published: March 2021

The Bioinfiltration Traffic Island (BTI) is a bioinfiltration rain garden that was retrofitted off an existing traffic island located at Villanova University, USA in 2001. Having been monitored since 2003, the BTI has quantitative hydrological data collected for the approximately two decades, making it a very valuable dataset for an in-depth analysis of the performance of the site.

The initial analysis comprises of a high-resolution analysis of rainfall event frequency along with resulting performance at the bioinfiltration rain garden. All rainfall events within the 15 years of collected data was discretized in to 2.5 mm, 2-hour bins. The binned rain events were then analyzed using a mass balance approach to understand how the different hydrological elements contribute to the ability of the site to treat incoming stormwater runoff. The second part of the analysis focuses on assessing the intensities of each of the recorded storms to understand its influence on the performance of the rain garden.

The third part of this analysis will comprise of studying the site’s ability to manage incoming runoff with the rain garden’s development over the fifteen years. The main focus will be to assess the performance of the site in the earlier stages and compare it to the performance seen in the latter stages with established vegetation. The binned rainfall events will be used to compare the performance of the BTI for storms with similar characteristics (similar precipitation amount and event duration) occurring in different stages of the timeline. The extensive dataset will additionally give insight to internal mechanisms such as evapotranspiration and infiltration occurring at the site and indicate how their contribution changes with the evolution of the site.

The overall analysis provides lessons into system components and aims to understand the interaction of the different hydrological elements within the rain garden. The objective is to use the findings in designing Green Infrastructure systems that can be optimized in their ability to manage incoming stormwater.
Contribution to the study of carbonatite complex of the Richat Dome (Mauritania)
Authors: Maham Eboubekrine Sedigh , Ouali Houssa , jébrak Michel , Ouabid Muhammed
Published: March 2021

The Richat Dome is a huge circular, slightly elliptical depression (~ 40 km in diameter) in the Proterozoic to Cambro-Ordovician sedimentary series of the NE part of the Mauritanian Taoudeni basin. This structure consists of a central zone that corresponds to a complex of dolomitic limestones and sedimentary rocks of Neoproterozoic age, cut by breccia silica and felsic volcanic rocks. A peripheral zone comprising Neoproterozoic to Late Ordovician sandstones and pelites into which carbonatite veins and two gabbroic annular dykes are injected.

Generally, the carbonatites represent a relatively rare type of igneous rock composed mainly of primary carbonate minerals (calcite and/or dolomite > 50 vol % of the rock) associated with phosphate minerals, silicates, and oxides. They contain the highest concentrations of rare earth elements (REE) of all igneous rocks. The carbonatites are also the main source of REE especially the light REE (La, Ce, Pr and Nd) as well as some critical metals such as Nb and Ta.

The aim of this study is to present a preliminary work on the carbonatite dykes of the Richat Dome: (1) detailed geological mapping of the various dykes, (2) petrographic, (3) mineralogical and (4) geochemical characterizations. The results obtained will be cross-referenced with other strategic deposits around the world
Net ecosystem exchange of CO2 and ecosystem respiration in two bogs in Estonia along disturbance gradient
Authors: Maddison Martin , Veber Gert , Kull Ain
Published: March 2021

Northern peatlands are important terrestrial carbon (C) stores, but their ability to sequestrate C is at delicate balance affected by management and also by climate change. The climate change causes less snow pack and warmer winters with faster water table drop in spring and drier summers in most boreal areas. Due to those changes natural peatlands may become C source instead of sink.

This study presents ecosystem respiration (ER) over five-year period and the annual estimates of net ecosystem exchange (NEE) of CO2 in Umbusi and Laukasoo in Estonia along disturbance gradient from drained to natural ombrotrophic bog. Both study sites locate next to the active cutaway peatlands. There were four CO2 flux measurements plots with three measurements points at different distance from the drainage ditch (10, 50, 100 and 200 m in Umbusi; 3, 40, 50, 125 m in Laukasoo) to form a water table depth and soil moisture gradient on both study sites. ER was measured using opaque static chamber throughout of the year in period 2012-2016. A vented and thermostated transparent plastic chamber with removable opaque cover was used for CO2 exchange measurements. NEE measurements occurred biweekly from April to December in 2015, totally were done 648 measurements. NEE was derived from modelling of ER and gross primary production with temperature, photosynthetically active radiation, water level and days of year (as phenological phase) as driving variables.

Annual mean NEE at four different distance from the ditch toward undisturbed area in Umbusi and Laukasoo were 0.37, 0.28, 0.15, 0.08 and 0.44, 0.34, 0.04, 0.21 kg C m-2 y-1, respectively. Although mean NEE was positive for all plots on both sites, there were also negative annual NEE values in some points in undisturbed plots (100 and 200 m from the ditch in Umbusi and 50 and 125 m in Laukasoo).

Average water level at four different distance from the ditch toward undisturbed area in Umbusi and Laukasoo during growing period (from the beginning of May to the end of October) in 2015 were -94, -45, -22, -22 and -124, -33, -21, -22 cm, respectively. Monthly mean air temperature and sum of precipitation were not different from the long-term measurements in studied growing period in 2015 while winter was significantly warmer.

Modelled ER remained high for cold period because of higher air temperature in 2015. Due to higher respiration rate from non-frozen peat layer in cold season, more CO2 was released back to atmosphere and annually less C was accumulated. Monthly mean air temperature for cold period was 3.5 ºC warmer than the long-term average.
An update on the 4D-LETKF data assimilation system for the wholeneutral atmosphere 
Authors: Koshin Dai , Sato Kaoru , Kohma Masashi , Watanabe Shingo
Published: March 2021

The four-dimensional local ensemble transform Kalman filter (4D-LETKF) data assimilation system for the whole
neutral atmosphere is updated to better represent disturbances with wave periods shorter than 1 day in the mesosphere and
10 lower thermosphere (MLT) region. First, incremental analysis update (IAU) filtering is introduced to reduce the generation
of spurious waves arising from the insertion of the analysis updates. The IAU is better than other filtering methods, and also
is commonly used for the middle atmospheric data assimilation. Second, the horizontal diffusion in the forecast model is
modified to reproduce the more realistic tidal amplitudes that were observed by satellites. Third, the Sounding of the
Atmosphere using Broadband Emission Radiometry (SABER) and Special Sensor Microwave Imager/Sounder (SSMIS)
15 observations in the stratosphere and mesosphere also are assimilated. The performance of the resultant analyses is evaluated
by comparing them with the mesospheric winds from meteor radars, which are not assimilated. The representation of
assimilation products is greatly improved not only for the zonal mean field but also for short-period and/or horizontally
small-scale disturbances. 
The potential of Sentinel-5P’s high spectral resolution for ocean applications
Authors: Bracher Astrid , Oelker Julia , Losa Svetlana , Altenburg Soppa Mariana , Richter Andreas , Rozanov Alexei , Brotas Vanda , Brito Ana C. , Gomes Mara , Costa Maycira , Rio Marie-Helene
Published: March 2021

Hyperspectral satellite data are a source of the top of the atmosphere radiance signal which can be used for novel algorithms aimed for observations of marine ecosystems and the light-lit ocean. Atmospheric sensors such as SCIAMACHY, GOME-2 and OMI have proven in the past to yield valuable information on phytoplankton diversity, sun-induced marine fluorescence, and the underwater light field, however at low coverage and spatial resolution. Within the ESA Sentinel-5p+ Innovation themes, we explore TROPOMI's potential for deriving the diffuse attenuation coefficient and the quantification of different phytoplankton groups. As commonly used for the retrieval of atmospheric trace gases, we apply the differential optical absorption spectroscopy combined with radiative transfer modeling (RTM) to infer these oceanic parameters. We present results on a measure describing the diminishing of incoming radiation in the ocean with depth, the diffuse attenuation coefficient KD. KD is derived by the retrieval of the vibrational Raman scattering signal in backscattered radiances measured by TROPOMI in the UV and spectral range which then is further converted to the associated KD using RTM. The final TROMPOMI KD data sets resolved for three spectral regions (UV-B+short wave UV-A, UV-A and short blue) agree well with in situ data sampled during an expedition with RV Polarstern in 2018 in the Atlantic Ocean.  Further, KD-blue compared to wavelength-converted KD(490nm) products (OLCI-A and the merged OC-CCI) from common, multispectral, ocean color sensors, show that differences between the three data sets are within uncertainties given for the OC-CCI product. Our study shows for the first time KD products for the UV spectral range retrieved from space based data. TROPOMI KD-blue results have higher quality and much higher spatial coverage and resolution than previous ones from SCIAMACHY, GOME-2 and OMI.  Additionally, first results on TROPOMI’s potential for retrieving three phytoplankton groups will be shown and compared to similar multispectral phytoplankton group data for the same time period and ocean region as shown for TROPOMI KD.
Astronomical calibration of a key Early Eocene Boreal section: implications for the climate response to the North Atlantic Igneous Province
Authors: Thibault Nicolas , Adatte Thierry , Spangenberg Jorge E.
Published: March 2021

Sections of the Fur formation exposed on the islands of Fur and Mors (N. Jutland, Denmark) expose well-preserved diatomites and over 140 interbedded ash layers spanning >1 Myr of the Early Eocene from the top part of the Paleocene-Eocene Thermal Maximum (PETM; 55.9 Ma). The Fur Formation is a Konzentrat-Lagerstätten with an extremely rich fish fauna as well as numerous exquisitely preserved invertebrates, vertebrates, plant material, and siliceous microfossils. Due to its peculiar bentonite record, the Fur formation also constitutes a reference for the North Sea area, recording phases of active North Atlantic Igneous Province (NAIP) volcanism. Recently, a sea-surface temperature (SST) record was derived from Tex86 values for this formation, showing anomalously cool SSTs immediately after the PETM (~11–23°C, Stokke et al., 2020) while near-freezing bottom-water temperatures (BWTs) have been inferred from clumped isotopes analysis of giant glendonite crystals (Vickers et al., 2020). The section is constrained by three radiometric dates of ash layers but cyclostratigraphic analysis of the section has proved difficult due to the apparent homogeneity of the diatomite and multitude of interbedded ash layers. We performed a high-resolution analysis of the magnetic susceptibility and carbon isotopes on bulk organics (δ13Corg) from across the top PETM to the top of the Silstrup Mb. The magnetic susceptibility depicts all the apparent ash layers as well as additional hidden ash layers with peaks of various heights, and thus constitutes an excellent stratigraphic tool for its potential of correlation to other sections and deep-sea sites of the North Atlantic. Our δ13Corg record is characterized throughout by periodicities of 65 to 90 cm and 3.6 m that match well precession and short-eccentricity cycles. Long-term trends and filtered 100 kyr cycles from our record correlate very well to the recent benthic δ13C Cenozoic compilation, leading to an astronomical calibration of the section which spans ~1300 kyr from 55.88 to 54.6 Ma. Our calibration allows for a precise illustration of the drastic contrast between the post-PETM warm tropical SSTs/BWTs and the surprisingly cool SSTs/BWTs of the North Sea.

References

Stokke, E.W., et al., 2020, Earth and Planetary Science Letters 544, 116388.

Vickers, M.L., et al., 2020, Nature Communications 11, 4713.
Mineral surface reactivity: mechanisms and concepts
Authors: Fischer Cornelius
Published: March 2021

Diagenetic reactions in sediments and sedimentary rocks are controlled by both fluid transport and surface reactivity. In this chapter, the major focus is on the effect of crystal surface reactivity and its variability. The “energetic landscape” of the solid material in contact with the fluid exerts control on reaction type, kinetics, and products. Critical surface processes include sorption, catalysis, dissolution, and precipitation. For diagenetic reactions, the sequence of processes and thus the potential inhibition of subsequent reactions due to surface modifications is of great interest. Consequently, the evolution of porosity and permeability is governed by the chronological sequence of surface reactions during the diagenetic history. This provides feedback to the fluid transport behaviour in the complex porous material. Because of this coupling, numerical approaches address the problem appropriately by the use of reactive transport codes. Pore scale treatment follows mechanisms at the scale of crystal surfaces that form the pore walls of the sedimentary rock. Such surface-chemical exercises require a parametrization that includes mechanistic understanding and connection to first-principles treatment. At larger scales, so-called continuum scale simulation treats fluid transport and fluid-solid reactions in a more generalized quantitative way. While such field-scale treatment is required and applied for multiple challenges, the small-scale mechanistic understanding is still a crucial part of geochemical research. The observed heterogeneity of surface reactivity requires specific upscaling strategies that are not yet reflected in large-scale analysis and predictions.
V3Geo: A cloud-based platform for sharing virtual 3D models in geoscience
Authors: Buckley Simon , Howell John , Naumann Nicole , Lewis Conor , Ringdal Kari , Vanbiervliet Joris , Tong Bowei , Maxwell Gail , Chmielewska Magda
Published: March 2021

V3Geo is a cloud-based repository for virtual 3D models in geoscience, allowing storage, searching tools and visualisation of 3D models typically acquired through photogrammetry (structure-from-motion), laser scanning or other laboratory-based 3D modelling methods. The platform has been developed to store and access 3D models at the range of scales and applications required by geoscientists – from microscopic, hand samples and fossils through to outcrop sections covering metres to tens of kilometres. A 3D web viewer efficiently streams the model data over the Internet connection, allowing 3D models to be explored interactively. A measurement tool makes it possible for user to measure simple dimensions, such as widths, thicknesses, fault throws and more. V3Geo differs from other services in that it allows very large models (consisting of multiple sections), is designed to include additional interpretations in future versions, and focuses specifically on geoscience through metadata and a classification schema.

The initial version of V3Geo was released in 2020 in reaction to the COVID-19 pandemic, with the aim of providing virtual tools in a time of cancelled field excursions, field-based courses and fieldwork. The repository has been accepting community contributions, based on a guideline for preparing and submitting high quality 3D datasets. Contributions are subject to a technical review to ensure underlying quality and reliability for scientific and professional usage. Model description pages give an overview of the datasets, with references, and datasets themselves are assigned Creative Commons licences. The 3D viewer can be embedded in webpages, making it easy to include V3Geo models in virtual teaching resources. V3Geo allows increased accessibility to field localities when travel or mobility is restricted, as well as providing the foundation for virtual field trips. The database currently includes around 200 virtual 3D models from around the world, and will continue to develop and grow, aiming to become a valuable resource for the geoscience community. Future updates will include tools to facilitate upload and technical review, interpretations and Digital Object Identifiers.
Post-fire soil water repellency, sorptivity, and the measurement of infiltration
Authors: Shillito Rose , Berli Markus , Ghezzehei Teamrat , Floyd Ian
Published: March 2021

Wildfires are frequently associated with the increased potential for runoff, flooding and debris flows during and after subsequent rainfall events. Specifically, wildfires can cause soils to become water repellent, which is believed to slow, if not halt, the infiltration of water into the soil. However, there exists no mechanistic way to determine the effect of post-wildfire water repellency on infiltration and runoff—until now. We have recently developed a simple physically-based model to account for the effect of water repellency on the soil hydraulic property of sorptivity. Further, since sorptivity is crucial to understanding the relationship between water repellency and post-fire infiltration, there is a need for a robust and accurate method to measure sorptivity in the field. All research was conducted in the laboratory using a fine silica sand, some of which was treated with ScotchgardTM to induce water repellency. Treated and untreated sand was mixed proportionally by weight to create various degrees of water repellent sand. Upward infiltration tests (wicking experiments) were used to validate the sorptivity model. Then, two common field methods (a 1D infiltrometer ring and a 3D tension infiltrometer) were used to measure downward infiltration and extract sorptivity data. Results showed that we able to predict sorptivity given the degree of water repellency and basic soil properties, that sorptivity measured using common field methods reflected the degree of water repellency, and that both downward infiltration measurement methods yielded similar sorptivity values.
Machine learning-based tools for water digitalisation
Authors: Slaimi Asma , Hegarty Susan , Regan Fiona , Scriney Michael , O’Connor Noel
Published: March 2021

Advanced technologies have proven to deliver significant outcomes in the water management sector. New technologies provide the capability to collect and correlate the information from remote devices, introducing smart tools that can leverage augmented intelligence for interpreting structured and unstructured, text-based or sensory data. However, most of the single feature or non-sequential prediction machine learning methods for understanding water quality achieve poor results due to the fact that water quality information exists in the form of multivariate time-series datasets.

At the catchment scale, there are many layers where relevant data needs to be measured and captured. For that, data warehouses play an essential role in decision support systems as they provide adequate information. 

In this paper, we started by extracting, transforming, cleaning and consolidating data from several data sources into a data warehouse. Then, the data in the warehouse was used to develop a computer tool to predict river water level using Artificial Neural Networks (ANNs), in particular, Long Short-Term Memory networks (LSTM). As the prediction performance is significantly affected by the model inputs, the feature selection step, which considers the multivariate correlation of water quality information in terms of similarity and proximity, is particularly important. The features obtained from the previous steps are the inputs to the prediction model based on LSTM, which naturally takes the time sequence of water quality information into account.

The proposed method is applied to two different catchments in the island of Ireland. Experimental results indicate that our model provides accurate predictions for water levels and is a useful supportive tool for water quality management. 

Ultimately, digitised representations of water environments will guarantee situational awareness of water flow and quality monitoring. The digitalisation of water is no longer optional but a necessity to solve many of the challenges faced by the water industry.

Keywords: Water digitalisation, water quality, data warehouse, machine learning, predictive model, LSTM.
The Integrated Ocean Carbon Observing System
Authors: Sanders Richard , Watson Andrew
Published: March 2021

The Oceans have taken up 20-25% of the carbon dioxide released to the atmosphere by human activities, in the process slowing the rate of climate change and giving us more time to adapt to and mitigate the effects of global warming. However this ‘sink’ has not been stable over the recent past and there is therefore a need to measure it in near real time with higher confidence than currently possible so that appropriate policy measures can be developed and implemented in response to any change. We have a wide array of tools including satellites, ship based and autonomous (gliders, moored, floats and surface vehicles) measuring systems which together with the associated data infrastructure can demonstrably come together to deliver this vision. These have largely been developed under short-term funding streams and, as a consequence do not currently deliver the robust, near real time, sustainable estimate of ocean C uptake that we believe is necessary to support international climate negotiations and the development of adaptation/mitigation strategies. We are currently developing a blueprint for the ‘Integrated Ocean Carbon Observing System’ which we believe will be as necessary for reliably forecasting climate over the next 5-10 years as meteorological observations currently are for forecasting weather over the next 5-10 days. In this contribution we will describe the key elements of this blueprint and outline a timeline for assembling them together to deliver an annual near realtime databased estimate of ocean carbon uptake to the annual COP in support of international climate negotiations.
SLR analysis employing consistent weather-driven corrections for atmospheric refraction, geophysical displacements, and gravity field variations
Authors: Koenig Rolf , Balidakis Kyriakos , Dobslaw Henryk , Zus Florian , Schuh Harald
Published: March 2021

Satellite Laser Ranging (SLR) observations are affected by weather variations. Mass redistributions within Earth‘s fluid envelope (the atmosphere, the oceans, and the continental hydrology) which are partly induced by the perpetual variability of weather, have an impact on (i) the orbits of satellites by inducing gravity field variations, and (ii) the locations of the ground stations by inducing elastic geophysical loading deformations. The SLR range observations between stations and satellites are also dependent on atmospheric conditions (mainly pressure, temperature, and humidity), induced by refraction. This work discusses the benefits that stem from applying consistently derived reduction models for transient gravity field variations, mass loading and atmospheric refraction effects in SLR data analysis. The models are driven from ECMWF‘s latest high-resolution reanalysis, the ERA5. SLR range observations to LAGEOS-1 and -2 serve as the geodetic data input. The software suite EPOSOC is employed to assess the effect of the application of the aforementioned reduction models and to quantify the benefits.
Constraint of GIA in Northern Europe and the North Sea with Geological RSL and GPS Data
Authors: Simon Karen , Riva Riccardo , Vermeersen Bert
Published: March 2021

This study focusses on improved constraint of the millennial time-scale glacial isostatic adjustment (GIA) signal at present-day, and its role as a contributor to present-day sea-level budgets. The study area extends from the coastal regions of northern Europe to Scandinavia. Both Holocene relative sea level (RSL) data as well as vertical land motion (VLM) data are incorporated as constraints in a semi-empirical GIA model. Specifically, 71 geological rates of GIA-driven RSL change are inferred from Holocene proxy data. Rates of vertical land motion from GNSS at 108 sites provide an additional measure of regional GIA deformation; within the study area, the geological RSL data complement the spatial gaps of the VLM data and vice versa. Both datasets are inverted in a semi-empirical GIA model to yield updated estimates of regional present-day GIA deformations. A regional validation is presented for the North Sea, where the GIA signal may be complicated by lateral variations in Earth structure and existing predictions of regional and global GIA models show discrepancies. The model validation in the North Sea region suggests that geological data are needed to fit independent estimates of GIA-related RSL change inferred from tide gauge rates, indicating that geological rates from Holocene data can provide an important additional constraint for data-driven approaches to GIA estimation. The geological proxy rates therefore provide a unique dataset with which to complement or validate existing data-driven approaches that use satellite era rates of change.
Using tree rings to assess the potential of thinning to alleviate drought stress in a dry forest of western Canada
Authors: Montwé David , Standish Audrey , Isaac-Renton Miriam , Axelson Jodi
Published: March 2021

Increasing frequency of severe drought events under climate change is a major cause for concern for millions of hectares of forested land. One practical solution to improving forest resilience may be thinning. There may be several potential benefits, chief of which is that drought tolerance could be improved in the remaining trees due to lower competition for resources and increased precipitation throughfall. By improving resilience to drought, this may increase productivity of the remaining trees while lowering risks of mortality. Such potential benefits can effectively be quantified with data from statistically-sound, long-term field experiments, and tree rings provide a suitable avenue to compare treatments. We work with an experiment that applied different levels of tree retention to mature interior Douglas fir (Pseudotsuga menziesii var. glauca) in a dry ecosystem of western Canada. The treatments were applied in the winter of 2002/2003, coinciding with the aftermath of a severe natural drought event in 2002. We used tree-rings to quantify the extent to which thinning improves recovery and resilience of treated trees as compared to non-thinned controls. Tree-ring samples as well as height and diameter data were obtained from 83 trees from 8 treatment units of the randomized experimental design. Indicators for resilience to drought were calculated based on basal area increments. Thinning substantially increased basal area increments at the individual tree level, but more importantly, led to significantly higher recovery and resilience relative to the control. The results of this tree-ring analysis suggest that thinning may be a viable silvicultural intervention to counteract effects of severe drought events and to maintain tree cover.
Estimation of Gross Primary Productivity of a raised bog ecosystem using satellite models and eddy covariance techniques under exceptional climatic conditions  
Authors: Ingle Ruchita , Bhatnagar Saheba , Ghosh Bidisha , Gill Laurence , Saunders Matthew
Published: March 2021

Peatlands are vital to the global carbon (C) cycle as they act as a significant C store and these systems in Ireland store between 1064 –1503 Gt C on ~20% of the land area. However, around 90% of this area has been drained and degraded by various anthropogenic activities and the emissions from these activities are approximately 3 million t C per year. A better understanding of the land-atmosphere C and greenhouse gas (GHG) dynamics is vital to halt these emissions and enhance the C sink strength of these ecosystems. Gross Primary Productivity (GPP) is a major part of the peatland carbon cycle and detailed knowledge of the spatial and temporal extent of GPP is imperative for improving our predictions of peatland ecology, biogeochemistry and carbon balance in response to global change. Eddy covariance (EC) techniques are widely used to measure carbon fluxes but can only account for fluxes within the flux footprint of the tower, and it is challenging to scale up data from EC towers to regional and global scales due to the limited number of towers and their geographic locations. This research assesses the relationship between remote sensing and ground-based measurements for a near-natural raised bog in Ireland using EC techniques and high-resolution Sentinel 2A satellite imagery. Vegetation indices (VIs) are one of the key input parameters for satellite-based GPP and most of the existing VIs have been developed for grassland, agriculture, and forest ecosystems. This study developed a hybrid index for raised bogs using multiple linear regression and six widely practiced conventional vegetation indices. Two approaches have been used in this study for estimating GPP using the LUE model. Initially, all the individual indices have been used to model the GPP, which was subsequently compared with the EC GPP to determine the performance of each index against the EC data. The model was run with meteorological data and satellite-derived vegetation indices. During the 2018 study period, the weather was exceptionally dry which made it challenging and rewarding at the same time as the hybrid index was developed for an exceptional year. It was crucial to test the performance of the hybrid index under more normal weather conditions with limited clear sky satellite imagery. Therefore, the hybrid index was validated for the year 2019 which had normal weather conditions. The hybrid index based modelled GPP showed a significant correlation with the EC GPP for both the years with an R2 > 0.95. Overall, this research has demonstrated the potential of combining EC techniques and the hybrid index along with satellite-derived models to better understand and monitor key drivers and patterns of GPP of raised bog ecosystems under different climate scenarios.
Modular designed Apps – an opportunity to standardize data collection methods and to encourage the reuse of software
Authors: Truckenbrodt Sina C. , Enderling Maximilian , Pathe Carsten , Borg Erik , Schmullius Christiane C. , Klan Friederike
Published: March 2021

Data collection strategies vary among different citizen science projects. This complicates the intercomparability of parameter values acquired in different studies (e.g., methodological and scale issues) and results in variable data quality. This creates problems regarding the merging of different data sets and hampers the reuse of data from different projects. Modular designed applications for mobile devices (Apps) represent a framework that helps to foster the standardisation of data collection methods. While they encourage the reuse of the software, they provide enough flexibility for an adjustment in accordance with the research question(s) of interest.

The currently developed App “FieldMApp” offers such a framework running under Android and iOS. The related concept includes predefined frame functionalities, like settings for the user account and the user interface, and adaptable application-related functionalities. The latter comprise several modules that are categorized as sensor test, basic functionality, parameter collection and data quality collection modules. The interdependencies of these modules are documented in a wiki. This enables an individual and context-based selection of functionalities. The FieldMApp is based on open-source software libraries (Xamarin, Open Development Kit (ODK), SQLite, CoreCLR-NCalc, LusoV.YamarinUsbSerialForAndroid, Newtonsoft.Json, SharpZipLib) and will be published as open-source software. Hence, the existing catalogue of functionalities can be augmented in the future. The premise for such extensions is that modules are published together with smart, universally applicable data quality recording routines and a proper documentation in the wiki.

In this contribution, we present the concept and the structure of the FieldMApp and some current fields of application that are related to the cultivation of arable land, soil mapping, forest monitoring, and Earth Observation. The extension of the functionality catalogue is exemplified by the newly implemented speech recognition module. A related quality recording routine will be introduced. With this contribution we would like to encourage citizens and scientists to elicit which requirements such an App should fulfil from their point of view.