bluuebunny/crossref_metadata_2025 huggingface dataset:
Wetland observatories for rewetting of drained peatlands (ReWeT-DK)
Authors: Petersen Rasmus Jes , Zak Dominik , Maagaard Astrid , Hoffmann Carl , Hans Andersen , Jesper Christiansen , Lars Elsgaard , Johannes Pullens , Paul Lærke
Published: March 2022

ReWet is currently establishing four observatories on drained peatlands in Denmark. These observatories will serve as platforms for ecosystem monitoring, experimental research, technological development and demonstration. The objective of ReWet is to facilitate climate smart management and land use change related to agriculture and forestry on peat soils  The ReWet observatories will focus on measurements of fluxes of greenhouse gases (GHG), energy, water and matter (including major nutrients and dissolved carbon) in the interface of the upper groundwater, soil, vegetation and the atmosphere under different rewetting strategies and land use combinations. The ecosystem monitoring will include biodiversity namely vegetation composition and soil microbial communities. The vertical movement of the peat surface will be monitored using dynamic radar reflectors. The monitoring and research carried out at the observatories will, in combination with nationwide  soil databases, enable development of science based national strategies for rewetting of temperate wetlands like in Denmark to achieve substantially lower GHG emissions at national scale, less nutrient pollution of aquatic ecosystems and increased landscape biodiversity.
Closing the gap between related databases: MetBase and the Astromaterials Data System (Astromat) plan for a common future
Authors: Hezel Dominik C. , Lehnert Kerstin A.
Published: March 2022

MetBase is the world’s largest database for meteorite compositions [1], currently hosted in Germany. MetBase started more than 20 years ago with collecting cosmochemical data by a private collector. Among others, the database consists of more than 500.000 individual data of, for instance, bulk and component chemical, isotopic and physical properties. Further, the database holds more than 90,000 references from 1492 until today. In 2006, the high value of the database was acknowledged by the Meteoritical Society with its Service Award. MetBase has seen substantial transitions in the past years from a purely commercial to a donation, free-of-charge database. The technical foundation has been completely modernised.

More recently, the Astromaterials Data System (AstroMat) has been developed as a data infrastructure to store, curate, and provide access to laboratory data acquired on samples curated in NASA’s Astromaterials Collections. AstroMat is intended to host data from past, present, and future studies. AstroMat is developed and operated by a team that has long-term experiences in the development and operation of data systems for geochemical, petrological, mineralogical, and geochronological laboratory data acquired on physical samples – EarthChem and PetDB.

Astromat and MetBase are two initiatives with two very different histories – but a shared goal. Astromat and MetBase therefore plan a common future. As a part of this, we are currently starting a project to make MetBase data fully FAIR (findable, accessible, interoperable and reusable, [2]), thereby implementing the recently established Astromat database schema [3], which is based on the EarthChem data model. Astromat and MetBase currently also work on new solutions for a long term and centralized hosting of both databases and a data input backbone.

Both MetBase and Astromat participate in the OneGeochemistry initiative, to contribute to the development of  community endorsed and governed standards for FAIR lab analytical data that will allow seamless data exchange and integration. Data access to the MetBase content will be provided both through Astromat and via a front-end that is part of the recently initiated ›National Data Infrastructure Initiative‹ (NFDI), covering all scientific areas [4].

References: [1] http://www.metbase.org. [2] Stall et al. 2019. Make scientific data FAIR. Nature 570(7759): 27-29. [3] https://www.astromat.org [4] https://www.dfg.de/en/research_funding/programmes/nfdi/index.htm [5] https://www.nfdi4earth.de
Investigating the VLBI scale behavior 
Authors: Le Bail Karine , Nilsson Tobias , Haas Rüdiger , Nyström Lindé Fredrik
Published: March 2022

Preliminary results of the ITRF2020 show that the Very Long Baseline Interferometry 
(VLBI) solution appears to have a scale problem, with larger scatter of the scale factor and a 
potential scale drift after around 2014. There are several possible reasons that have been 
brought into discussion, ranging from specific VLBI stations having technical problems to 
the use of various geophysical models in the VLBI data analysis, such as atmospheric 
pressure loading and post-seismic deformation models, and other models to account for, e.g., 
thermal and gravitational deformation of radio telescopes. This work focuses on the impact of 
such reasons on the VLBI scale. We first investigate the VLBI contribution of the Onsala 
Observatory which made used of the software package ASCOT and that enters in the IVS 
combined solution, and we then expand to the IVS combined solution and other individual 
contributions. 
Assessing Uncertainties and Variability 34 Years of Surface Radiative Fluxes and Radiative Closure Using GEWEX SRB Release4-IP
Authors: Stackhouse Paul , Cox Stephen , Mikovitz J. Colleen , Zhang Taiping
Published: March 2022

The NASA/GEWEX Surface Radiation Budget (SRB) project produces 3-hrly shortwave and longwave surface and top of atmosphere radiative fluxes for the 1983-near present time period. The new Release 4 Integrated Product (IP) uses the newly recalibrated and processed ISCCP HXS product as its primary input for cloud and radiance data, replacing ISCCP DX with a ninefold increase in pixel count (10 km instead of 30 km).  This first version retains a 1°x1° resolution enabling intercomparison against previous versions and other data sets such as CERES, but spans 34 years from July 1983 through June 2017 and was announced by Kummerow et al. 2019 (GEWEX News). This new IP product also uses an atmospheric temperature and moisture dataset known as nnHIRS and other parameters such as near surface and skin temperatures from SeaFlux and LandFlux data sets.  In addition to the input data improvements, several important algorithm improvements have been made since Release 3. These include recalculated SW atmospheric transmissivities and reflectivities, updated ocean and snow/ice albedos, and variable total solar irradiance consistent with SORCE measurements. The LW code has been updated to improve the optical property treatment for clouds and aerosols are included in this version.  Radiative treatment of ice clouds is also improved in the LW. The variable aerosol optical properties for the SW and LW are specified using a detailed aerosol history from the Max Planck Institute Aerosol Climatology (MAC).

Here we present an assessment of the LW radiative fluxes and the uncertainty of those fluxes relative to the various inputs to surface SW/LW flux measurements from BSRN and PMEL buoys measurements.  We review the validation of the SW and LW fluxes and then in terms of time series and then assess the products in terms of their long-term variability of the surface SW and LW net fluxes compared to multiple other data products including atmospheric reanalysis products.  The comparisons of radiative estimates to observations are performed at various temporal scales and aimed at investigation of agreement at longer time averages but accessing potential change in diurnal magnitude and daily variability.  Utilizing this uncertainty information, to access long-term variability of surface radiation components at selected region and global scales, considering satellite sampling/calibration “artifacts” as necessary.  At the longer time scales, the net SW and net LW the TOA and surface have implications toward closure of the energy budgets at the surface, we assess these compared to other studies on energy budget closure for the same selected global and regional scales.
Influence of horizontal resolution on aerosol hygroscopic growth effects in urban andremote boundary layers in the context of climate impact and adaptation studies
Authors: Metzger Swen , Feigel Gregor , Steil Benedikt , Rémy Samuel , Christen Andreas
Published: March 2022

We share our experiences for impact and adaptation studies, by presenting results of a climate modelling study, which is based on ERA5 data at different horizontal resolutions, i.e., down from approximately 300 km to 25 km. The ERA5 data is used as a meteorological constraint (nudging) to perform a numerical model study on the influence of horizontal resolution on aerosol hygroscopic growth effects on meteorology in urban and remote atmospheric locations. For this sensitivity study we only switch on/off the associated aerosol water mass. Aerosol water is crucial form climate impact and adaptation studies as it links air pollution with weather and climate through direct and indirect radiative feedbacks. We try to separate urban from continental-scale effects using the EMAC atmospheric chemistry climate and Earth system model. EMAC is applied globally in various horizontal resolutions, in a set-up similar to our previous PMAp evaluation study (https://www.eumetsat.int/PMAp), i.e., resolving weather time-scales. We compare our EMAC results of the aerosol optical depth (AOD) against CAMS reference simulations (40 km), various satellite data (MODIS-Aqua/Terra, PMAp) and AERONET surface observations (~ 30km radius around the instrument). While CAMS REA includes AOD data assimilation (Modis/PMAp), EMAC calculates the AOD ab initio from size-resolved aerosol hygroscopic growth without any data assimilation, and with an option to include aerosol-cloud feedbacks. Our results show that the EMAC AOD results are within the range of CAMS and satellite AOD. Aerosol water effect on AOD is noticeable for nudged and free running EMAC versions at both, urban and remote locations. The aerosol water effect is larger for free running EMAC versions, and more pronounced for urban AERONET sites, e.g., Hamburg, Karlsruhe, Thessaloniki, Zaragoza. The moisture feedback with air pollution is resolution dependent (time and space). Generally, this becomes more relevant with increasing resolution due to finer moisture and air pollution gradients, which is an indication for the importance of horizontal resolution for impact and adaptation studies.
Spatiotemporal evolution of snow depth distribution on Antarctic sea ice
Authors: Maksym Ted , Mei M. Jeffrey , Wever Nander , Trujillo Ernesto , Leonard Katherine , Ackley Steve , Weissling Blake , Williams Guy , Singh Hanumant
Published: March 2022

Snow cover is a primary control on Antarctic sea ice mass balance as it controls basal ice growth and snow ice formation. It is also a primary control on the surface energy budget, partitioning of solar radiation, and sea ice biological communities. Finally, knowledge of its distribution is critical for accurate estimation of sea ice thickness from satellite altimeters. The floe-scale distribution of snow is highly variable, driven by wind redistribution over complex sea ice surface topography. Yet, our understanding of the seasonal evolution of snow depth distribution is poor and its representation in models is simple or non-existent.We present observations of the three-dimensional distribution of snow depth, ice thickness, and surface topography from a suite of cruises in the Weddell, Bellingshausen, Ross, and East Antarctic Seas that span the full growth season – from autumn, through winter, to late spring. The distribution of snow depth changes from a right-skewed distribution in autumn as snow initially accumulates around ridges to a gaussian by spring as snow deepens and ice surface topography roughens. While the distribution is spatially complex, the spectral distribution of snow features is similar across seasons. Using these data we construct a simple statistical model for the seasonal evolution of floe-scale snow depth distribution. We also compare our results to prior observations from drilling transects and larger-scale airborne observations from NASA’s Operation IceBridge. For the latter we use a convolutional neural network to demonstrate that the surface topography can be used as a reliable predictor of the snow depth distribution at regional scales.
Time-dependent forcing in the geosciences and in epidemiology
Authors: Ghil Michael
Published: March 2022

For many of us, the Covid-19 pandemic brought long-time scientific interest in epidemiology to the point of involvement. An important aspect of the evolution of acute respiratory epidemics is their seasonal character. Our toolkit for handling seasonal phenomena in the geosciences has increased in the last dozen years or so with the development and application of concepts and methods from the theory of nonautonomous and random dynamical systems (NDSs and RDSs). In this talk, I will briefly:

Introduce some elements of these two closely related theories.

Illustrate the two with an application to seasonal effects within a chaotic model of the El

Niño–Southern Oscillation (ENSO).

Introduce to a geoscientific audience a simple epidemiological “box” model of the

Susceptible–Exposed–Infectious–Recovered (SEIR) type.

Summarize NDS results for a chaotic SEIR model with seasonal effects.

Mention the utility of data assimilation (DA) tools in the parameter identification and

prediction of an epidemic’s evolution

References

- Chekroun, M D, Ghil M, Neelin J D (2018) Pullback attractor crisis in a delay differential ENSO model, in Nonlinear Advances in Geosciences, A. Tsonis (Ed.), Springer, pp. 1–33, doi: 10.1007/978-3-319-58895-7

- Crisan D, Ghil, M (2022) Asymptotic behavior of the forecast–assimilation process with unstable dynamics, Chaos, in preparation

- Faranda D, Castillo I P, Hulme O, Jezequel A, Lamb J S, Sato Y, Thompson E L (2020) Asymptotic estimates of SARS-CoV-2 infection counts and their sensitivity to stochastic perturbation<? Chaos, 30(5): 051107, doi: 10.1063/5.0009454

- Ghil, M (2019) A century of nonlinearity in the geosciences. Earth & Space Science 6:1007–1042, doi:10.1029/2019EA000599

- Kovács, T (2020) How can contemporary climate research help understand epidemic dynamics? Ensemble approach and snapshot attractors. J. Roy. Soc. Interface, 17(173):20200648, doi: 10.1098/rsif.2020.0648
Cover crops as a method of enhancing soil moisture and nutrient retention on arable farmland
Authors: Thomas Robert , Ahmed Joshua , Johnson Joshua
Published: March 2022

Flooding affects >300 million people each year and causes loss of life, damage to infrastructure, and long-term mental and physical health problems. Across many parts of the globe, climate change is projected to increase the magnitude, frequency, and intensity of rainfall events, thus exacerbating future flood risk and increasing the demand for flood alleviation schemes. Agricultural land covers 39% of Europe, and as such intercepts a significant fraction of precipitation. Agricultural intensification has increased soil compaction and decreased soil porosity and permeability, thus decreasing infiltration, storage and groundwater recharge. Here, we report on experiments that aim to constrain the effects of using cover crops to increase soil porosity and permeability and hence decrease runoff during rainfall events in three arable fields in East Yorkshire, UK.

Half of each field was treated with a cover crop between harvest and winter cultivation, and the organic matter of this crop was incorporated into the soil. The second half of each field was used as a control. A suite of methodologies is being used to assess the long-term influence of this extra organic matter content on soil structure, health and permeability:

An array of soil moisture loggers (Delta-T PR2/4, DalesLandNet MKII, GroPoint Profile 2625-N-T-4) was deployed in each field to provide long term soil moisture data at high temporal resolution;

Roaming soil moisture measurements (Campbell Scientific HydroSense II) were used to increase spatial coverage and resolution;

Laboratory measurements of soil density, ambient soil moisture content, porosity, permeability, and nutrient content (nitrogen, phosphorous and potassium); and

A 3D MODFLOW model parameterised with collected data was used to assess the long term impact of increased soil porosity and permeability on rainfall transmission in to surface water drainage systems.

Preliminary results suggest that enhanced organic matter – delivered through cover crops – increases soil nutrient and moisture retention and decreases the peak flow stage in adjacent drainage channels after intense rainfall events. These observations suggest soil restoration may provide an important mechanism for attenuating flood peaks under future climate scenarios.
Stratospheric observations of acoustic-gravity waves from the Hunga-Tonga eruption
Authors: Podglajen Aurélien , Garcia Raphaël , Gerier Solene , Hauchecorne Alain , Hertzog Albert , Le Pichon Alexis , Lott Francois , Millet Christophe
Published: March 2022

In the frame of the Strateole 2 balloon project, 17 long-duration stratospheric balloons were launched from Seychelles in fall 2021. At the time of the main eruption of Hunga-Tonga on January 15 2022, two balloons were still in flight over the tropical Pacific, respectively at altitudes of 20 and 18.5 km, and distances of 2,200 and 7,600 km from the volcano. The balloon measurements include wind, temperature and pressure at a sampling rate of 1 Hz. Those observations of this extreme event at that altitude are unique.

In this presentation, we will describe the observations of multiple wave trains by the balloons. The signature of the Lamb wave and infrasounds are particularly striking. The characteristics of the eruption and its scenario will be examined using a synergy of stratospheric in situ observations, ground observations and geostationary satellite images. Finally, we will discuss the complementarity of balloon observations with respect to the ground network due to their altitude and geographic location with respect to the source.
Relaxation timescales after small and large earthquakes: similarity and controls from seismic velocity changes estimated in Patache, Chile.
Authors: Illien Luc , Sens-Schönfelder Christoph , Ke Kuan-Yu , Turowski Jens , Hovius Niels
Published: March 2022

Ground shaking induced by earthquakes often introduces transient changes in subsurface
rock's physical properties. Evidences for these changes come from estimated
seismic velocity changes that show co-seismic velocity drops, which are succeeded by a
phase of recovery (the so-called relaxation process). Because this transient behaviour may
influence hydraulic properties, friction properties in fault zones, material strength or landslide rates,
understanding the duration of the relaxation is important for post-earthquake hazard
mitigation. However, there is poor constraint on the recovery timescale, especially after
small seismic events. In this study, we present seismic interferometry results obtained
from a  seismic array at the Patache field site in Chile. Thanks to high 
averaging capabilities with this dense deployment of 13 stations, we are able to resolve relative seismic velocity
changes (3-6 Hz) at a 10-minutes resolution following a moderate seismic event (PGV ~
5 mm/s). After inferring the 1D shear velocity profile of our field site, we report a velocity
drop of ~0.4 % in the first 10 minutes after ground shaking, that precedes a recovery to
~50% of the initial pre-event value during the 48 hours following the event. We compare
this high resolution velocity change observation with a longer term, multi-annual velocity time-series that we obtained at
the same site and which exhibits the recovery induced by 2 large earthquakes (the 2007 Mw 7.7
Tocopilla and the 2014 Mw 8.2 Iquique). This combination of short and long observations allows us to
discuss the effect of ground shaking levels and earthquake sequences on the observed
relaxation timescales and highlights its key controls to possibly derive meaningful
predictive relationship for transient mechanical changes following earthquakes.
Seismic constraints on the hydrothermal circulation and magmato-tectonic interactions beneath Lucky Strike volcano, Mid-Atlantic Ridge
Authors: Bohidar Soumya , Crawford Wayne , Cannat Mathilde
Published: March 2022

Lucky Strike volcano is the central edifice of the Lucky Strike segment, Mid-Atlantic Ridge. Its summit overlies an axial magma chamber (AMC), 3-3.8 km beneath the seafloor, and hosts one of the largest known deep-sea hydrothermal fields. Local seismicity beneath the hydrothermal field has been monitored since 2007 as a part of the EMSO (European Multidisciplinary Seafloor and water column Observatory)-Azores observatory by 5 OBSs with yearly redeployments. From the 2007-2019 earthquake catalog, the primary process for the seismicity observed beneath the volcano region is proposed to be thermal contraction at the base of the hydrothermal circulation. In this interpretation the most seismically active zones represent the domains of maximum heat extraction at the base of the hydrothermal system. Here we present the evolution of the hydrothermal system controlled by magmato-tectonic interactions in the frame of this interpretation.

First, we observe two shifts of the most seismically active zones from ~1.4km North-Northwest of the hydrothermal field as documented in 2007-2009 to ~0.7km to North of the field in between 2010-2013 and then Eastward for about ~0.6km from 2010-2013 to 2015-present. These shifts, of the order ~600-700 meters, occurring at time scales of a few years, might be driven by one or several of the following mechanisms: the relocation of the maximum heat extraction zone to a shallower region of the AMC after significant heat extraction, the relocation to a recent magmatic injection,  and/or a tectonically-driven change in the hydrothermal fluid pathways.

Second, we observe three main Higher Seismic Activity (HSA seismic rate > 18 events/week) periods: April-June 2009, August-September 2015 and April-May 2016. The 2009 HSA period lasted ~13 weeks and the events clustered just above the AMC, while the 2015 and 2016 HSA periods lasted ~4-5 weeks, with events forming a narrow, dike-shaped cluster between the AMC  and just few meters below seafloor. HSA periods are characterized by deeper events and the occurrence of a few higher magnitude events (ML > 1.0). In between HSA periods, the seismicity tends to align along the trace of an inward dipping fault that bounds the narrow axial graben to the west, at the top of the volcano. The HSA periods can thus be interpreted as periods of maximum heat extraction by the hydrothermal circulation, possibly obscuring the background fault-related seismicity that is detected in periods of lesser seismic activity.
The importance of functional diversity in forest productivity is driven by environmental stress in Italy 
Authors: Lammerant Roel , Rita Angelo , Borghetti Marco , Muscarella Robert
Published: March 2022

The role of forest biodiversity in supporting ecosystem functioning is remarked to be context-dependent, and changes in environmental conditions could alter the shape of biodiversity-ecosystem functioning (BEF) relationships. However few studies have explored the processes underlying shifts in BEF relationships along abiotic gradients, which limits our ability to predict how the BEF relationship will respond to the rapid future changes in environmental conditions caused by climate change. In this study, we sought to test (i) how a water limitation gradient shapes the functional composition and diversity of forests, (ii) how functional composition and diversity of trees relate to forest productivity, and (iii) if functional diversity is more strongly related to productivity in the Mediterranean or temperate climate. To address these points, we created a functional trait data set covering traits of most of the tree species within the Italian peninsula, using forest surveyed data sets from the National Forest Inventory. We found that functional composition varied with water limitation as tree communities tended to have more `conservative` resource strategies (e.g., low specific leaf area and high wood density) under increased water limitation. Functional diversity´s response was highly variable, however, increased water limitation has been found to enhance also functional diversity in the temperate domain. Biodiversity positively influenced forest productivity through a combination of mass ratio and niche complementary effects in Italian forests, but the relative importance of these effects is dependent on the functional trait and bioclimate considered. Niche complementary effects showed a more predominant effect on productivity in the Mediterranean compared to temperate forests. Overall, our results suggest that biodiversity plays an important role in driving forest productivity under more environmental stressed conditions by promoting beneficial interactions between species and complementarity in resources.
Potential redistribution of major staple crops buffer climate change impacts on agriculture in Africa 
Authors: Chemura Abel , Gornott Christoph
Published: March 2022

The geographical range of agricultural crops is shifting under climate change as crop potential either increase or decrease. In this study, we assess the shifts in crop suitability for six major staple crops (maize, sorghum, millet, rice, cassava and wheat) across Africa by 2050 to understand crop switching and/or diversification as adaptation to climate change. While we observe that climatic suitability for four of the six crops will decrease in Africa, our results show that considering crop replacement with a more suitable crop will maintain agricultural potential in West and East Africa. Millet production can replace many maize, sorghum, cassava and wheat producing areas while fewer areas can switch to maize or wheat by 2050. We therefore provide a new empirical approach that can be used for crop shifting analysis by providing estimates of the potential in new areas. We conclude that redistribution of major staple crops according to their potential significantly reduces climate change impacts, assuming that new crops can meet calorie demands. Therefore, if farmers will grow the most suitable crops in their locations and if production can be transported and exchanged through markets between most suitable areas for a crop to less suitable areas, then climate change impacts on agriculture and food security will be reduced.
The radiocarbon reservoir age of coastal Greenland waters
Authors: Pearce Christof , Özdemir Karen Søby , Forchhammer Ronja Cedergreen , Detlef Henrieka , Olsen Jesper
Published: March 2022

Radiocarbon (14C) dating is the standard method for obtaining the age of marine sediments of Holocene and late Pleistocene age. For accurate calibrations, however, this tool relies on precise knowledge of the local radiocarbon reservoir age of the surface ocean, i.e. the regional difference (ΔR) from the average global marine calibration dataset. This parameter has become impossible to measure from modern material samples because of 14C contamination from extensive testing of thermo-nuclear bombs in the second half of the twentieth century. The local reservoir age can thus only be calculated from the radiocarbon age of samples collected before AD 1950 or from sediment records containing absolute age markers, derived from e.g. tephrochronology or paleomagnetism.

Knowledge of the marine reservoir age around Greenland is sparse and relies on work by a few studies, represented by measurements clustered in local patches. In this study we add new radiocarbon measurements on samples from historical mollusk collections from Arctic expeditions of the late 19th and early 20th Century. The 92 new samples are from central east Greenland and the entire western Greenland coast. Although the new data is mostly coastal, it includes a few deeper sites from the Labrador Sea and northeastern North Atlantic Ocean, where deep waters were found to be very young. Together with existing measurements, the new results are used to calculate average ΔR values for different regions around Greenland, all in relation to Marine20, the most recent radiocarbon calibration curve. Despite the significant addition of new measurements, very few data exist for southeastern Greenland, while no data at all is available for the Arctic Ocean coast in northern Greenland.
Soil microbial co-occurrence networks and functioning along an aridity gradient in Atlantic coastal dunes
Authors: Fernández Alonso María José , Rodríguez Alexandra , Ochoa-Hueso Raúl , Maestre Fernando T. , Durán Jorge
Published: March 2022

Atlantic coastal dunes are priority conservation areas highly sensitive to climate change. In the Iberian Peninsula, a large part of the coastal dunes are drylands where the chronic shortage of water acts as a major driver of the ecosystem structure and functioning. The predicted increase in aridity by the end of this century may compromise key ecosystems aspects in drylands, such as biotic cover, vegetation productivity and soil fertility. We know little about how changes in aridity and biotic cover may affect the abundance and diversity of soil microbial communities in coastal dunes, and as such their assembly and ecological interaction networks.

We investigated whether the exposure to different aridity regimes can induce differences in microbial co-occurrence networks as well as alter their spatial heterogeneity. Specifically, we aim to (1) assess whether soil fungal and bacterial networks respond differently  and (2) test the role of the biotic cover driving the bacterial and fungal network relationships, the soil attributes and functions. To that end, we used a climosequence of dune systems with minimal variation in the soil type that covered a wide range of aridity conditions including humid, dry-subhumid and drylands in the coastline of Portugal and Spain (~1500 km).

Our results show that aridity decreased the biotic cover, favoured the formation of shrub vegetation patches and negatively affected microbial diversity, organic matter content and potential nitrogen mineralisation in soils. We also observed that the biotic cover exerts a strong control on soil attributes whose effects depend on the degree of aridity (e.g. formation of fertile islands in arid areas and different control of soil inorganic nitrogen forms in wetter areas). At an ecosystem level, increases in aridity resulted in a strong increase in the coupling of the soil microbial network until a specific threshold (values of aridity index (P/ETP)= 0.5-0.6) beyond which it remained constant. Soil bacterial networks showed lower stability against changes in aridity than fungal networks. Surface microsites strongly drove the interactions among soil bacterial groups, but much less so for fungal groups. Our results suggest that climate change, through increased aridity and associated loss of the biotic cover, will have important implications for microbial communities and soil functioning in these coastal dune systems.
Developing a Next Generation Platform for Geodetic, Seismological and Other Geophysical Data Sets and Services
Authors: Trabant Chad , Berglund Henry , Carter Jerry , Mencin David
Published: March 2022

The Data Services of IRIS and the Geodetic Data Services of UNAVCO have been supporting the seismological and geodetic research communities for many decades.  Historically, these two facilities have independently managed data repositories on self-managed systems.  As part of merger activities between IRIS and UNAVCO, we have established a project to design, develop and implement a common, cloud-based platform.  Goals of this project include operational improvements such as cost-effectiveness, robustness, on-demand scalability, significant growth potential and increased adaptability for new data types.  While we expect a number of operational improvements, we anticipate a number of additional benefits for the research communities we serve.

The new platform will provide services for data queries across the internal repositories.  This will provide researchers with an easier path to discovery, and access to integratable data sets of related geophysical data.

Researchers will be able to conduct their data processing in the same, or data-proximate, cloud as the platform, taking advantage of copious and affordable computation offered by such environments.  Following the paradigm of moving the computation to the data, this will avoid the time and resource consuming need to transfer the data over the internet.  Furthermore, the adoption of cloud-optimized data containers and direct access by researchers will support efficient processing.  In cases where transferring large volumes of data are still necessary, the large capacity of cloud storage systems will allow enhanced mechanisms such as Globus for transfer, which we will be exploring.

For many users a transition of the data repositories to a new environment will be nearly seamless.  This will be made possible by implementing many of the same services already supported by the current facilities, such as the suite of FDSN web services.  The project is currently in a prototyping stage, and we anticipate having a complete design by the end of 2022.  We will report on the status of the project, anticipated directions and challenges identified so far.
The impact of the spheromak tilting in space weather modelling
Authors: Asvestari Eleanna , Rindlisbacher Tobias , Pomoell Jens , Kilpua Emilia
Published: March 2022

Accurate reconstruction of the magnetic field topology of coronal mass ejections (CMEs) is essential in space weather forecasting and thus in the spotlight of modelling efforts. The spheromak, a force-free, axisymmetric configuration within which plasma is confined by a twisted magnetic field that fills a spherical volume, is at the moment the most commonly employed flux rope model, which has entered numerous published event studies. Despite its widespread application, not much attention has been paid to the spheromak tilting, which not only affects the spheromak's orientation in the modelling domain, but also its direction of propagation. This can lead to implications when comparing simulation output to observations. The tilting of the spheromak occurs when its magnetic moment is at an angle with the ambient magnetic field. In this case a torque is exerted on the spheromak, forcing it to rotate, so that its magnetic moment aligns to the ambient magnetic field. In our study we used EUHFORIA to investigate the spheromak tilting under different conditions. We developed a method to monitor the spheromak's position and orientation in the EUHFORIA simulation output, and we quantified how the spheromak's total drift and rotation angle depend on various input parameters. We find that the spheromak experienced tilting in all studied scenarios resulting often in a significantly changed orientation to that which it had during insertion. We emphasize that in space weather modelling it is crucial to take into consideration the spheromak tilting, in particular when comparing the model output to observations.
ViCTool: An open-source tool for vegetation indices computation of aerial raster images using python GDAL 
Authors: Triana-Martinez Jenniffer Carolina , Fernandez-Gallego Jose A. , Barrero Oscar , Borra-Serrano Irene , De Swaef Tom , Lootens Peter , Roldan-ruiz Isabel
Published: March 2022

For precision agriculture (PA) applications that use aerial platforms, researchers are likely to be interested in extracting, study and understanding biophysical and structural properties in a spatio-temporal manner by using remotely sensed imagery to infer variations of vegetation biomass and/or plant vigor, irrigation strategies, nutrient use efficiency, stress, disease identification, among others. This requires measuring spectral responses of the crop at specific wavelengths by using, for instance, Vegetation Indices (VI). However, for the analysis of this spectral response and its heterogeneity and spatial variability, a large amount of aerial imagery (data) must be collected and processed using a photogrammetry software. Data extraction is often performed in a Geographic Information System (GIS) software and then analyzed using (in general) statistical software. On the one hand, a GIS is used for the collection of resources to manipulate, analyze, and display all forms of geographically referenced information. In this regard, Quantum GIS (QGIS) is one of the most well-known open-source software used which provides an integration of geoprocessing tools from a variety of different software libraries. QGIS is widely used to obtain VI computations through the raster calculator, although, this computation is performed with band rasters manually provided by the user; one by one, which is time-consuming. On the other hand, QGIS provides a Python interface to efficiently exploit the capabilities of a GIS to create similar plugins, but this can be a non-trivial task. In this work, we developed a specific and QGIS independent semi-automatic tool called ViCTool (Vegetation index Computation Tool) as a free open-source software (FOSS) for large amount of data extraction to derive VIs from aerial raster images in a certain region of interest. This tool has the option of extracting several multispectral and RGB VIs employing Blue, Green, Red, NIR, LWIR, or Red edge bands. The user must provide the input folder path containing one or more raster band folders, the shapefile with the regions of Interests, an output path to store the output VI rasters, and the file containing the VI computations. ViCTool was developed using Python PyQT for designing the User Interface (UI) and Python GDAL for raster processing to simplify and speed up the process of calculating a large amount of data intuitively.
Geochronology of sediments as a tool to identify lost geological features - a case study from the Mesozoic sedimentary succession of the Kutch Basin, western India
Authors: Chaudhuri Angana , Dunkl István , Schönig Jan , von Eynatten Hilmar , Das Kaushik
Published: March 2022

Sedimentary successions capture the history of geological features and events observable on present-day earth surface as well as those exposed earlier but currently buried or lost to erosion. The Mesozoic rocks in the Kutch Basin (western India) deposited between Middle Jurassic and Early Cretaceous reveal interesting provenance information on lost orogens and buried basins. The southwesterly sediment transport direction indicates north and northwest of the Indian subcontinent as the source area. Detrital zircon and monazite U-Th-Pb geochronology identify dominant sediment input from source rocks equivalent to the late Neoproterozoic Pan-African orogeny (500–650 Ma) along with substantial input from those equivalent to the Cambro-Ordovician Bhimphedian (aka Kurgiakh) (400–500 Ma) orogeny. All other contributing source rocks (ranging from 700 Ma to 3300 Ma) are traceable to the source area following the sediment transport direction. However, outcrops of crystalline rocks with zircon and monazite ages corresponding to the dominant age components are virtually lacking. Rocks equivalent to the Pan-African orogeny are found only as sparse isolated outcrops in the source area. In contrast, this orogeny is well reported from the southern granulite terrain (India), Madagascar, Seychelles and Eastern Africa. Therefore, considering the position of continents during the Mesozoic and the predominance of a 500–650 Ma sediment source in the Kutch Basin, the Pan-African orogenic belt possibly extends to north and north-western India. The current dearth of these outcrops suggests extensive erosion during the Mesozoic greenhouse climate and/or burial under the Deccan Flood Basalts. The other dominant source (400–500 Ma), equivalent to the Bhimphedian orogeny, currently reported as isolated outcrops in the Himalayan-fold-thrust belt (northern India) might have been disturbed and buried by thrusting during the Cenozoic Himalayan orogeny. This study also reveals a large gap of nearly 280 Ma between the youngest detrital zircon (458 Ma) and the depositional age (~170 Ma). This gap may be explained by (i) input of recycled sediment from an older basin, and/or (ii) absence of younger metamorphic events in the source area. The evidences of sediment recycling from thin-section petrography and ultra-stable heavy mineral assemblages (dominated by zircon, rutile and tourmaline) suggest the possibility of a so far unknown (buried or completely eroded) sedimentary basin older than the Kutch Basin. The on-going study of detrital rutile grains in these sediments may provide an alternative explanation for the 280 Ma gap by revealing lower temperature metamorphic events that are not recorded by U-Th-Pb ages of zircon and monazite.
Drought Cycle Analysis to evaluate the influence of a dense network of small reservoirs on drought evolution
Authors: Ribeiro Neto Germano , Melsen Lieke , S. P. R. Martins Eduardo , W. Walker David , van Oel Pieter
Published: March 2022

Drought-affected regions often contain high densities of small reservoirs, usually informally built, as drought-coping mechanism. These structures influence socio-hydrological dynamics and have the potential to alter hydrological processes relevant to drought emergence and development. This study aimed to analyze the influence of a high concentration of small reservoirs on the intensification and evolution of drought events. We present an innovative method, which we call “Drought Cycle Analysis”, that tracks the concomitance of precipitation and water storage deficit and associates this with four drought stages: Wet Period, Meteorological drought, Hydro-meteorological drought and Hydrological drought period. The methodology was tested for the Riacho do Sangue River watershed located in the semi-arid region of northeast Brazil. We used a combination of satellite imagery (Landsat 5, 7 and 8) and an empirical equation to estimate the volume stored in the dense network of small reservoirs. Using the Drought Cycle Analysis, we show that the unmonitored small reservoirs induced and modified drought events, extending the duration of hydrological drought on average by 30%. Furthermore, this extension can double for specific drought events. The Drought Cycle Analysis method proved useful for monitoring and comparing the evolution of different drought events, in addition to being applicable as an auxiliary tool in the improvement of water resources management of large reservoirs. This study demonstrates the importance of considering small reservoirs in water resource management strategy development for drought-prone regions.
Terminal-Cretaceous Dinosauria and Pterosauria from a Cretaceous-Paleogene mass-death assemblage, Hell Creek Formation, U.S.A.
Authors: DePalma Robert , Unwin David , Oleinik Anton , Burnham David , Gurche Loren , Klingler Jeremy , Larson Peter , Beasley Thomas , Bergmann Uwe , Edwards Nicholas , Wogelius Roy , Egerton Victoria , Manning Phillip
Published: March 2022

Dinosaurs and pterosaurs, critical components of late Mesozoic terrestrial biomes, have thus far never been reported in-situ from deposits immediately below the Cretaceous-Paleogene (KPg) boundary. Strata from the KPg boundary preserve worldwide evidence of a massive cosmic impact that resulted in grave consequences for Earth’s biota, triggering a rapid global mass extinction that ultimately claimed ~75% of species. While trends in long-term biotic effects are well-documented, little is known about the fate of biota coeval with the impact because well-preserved fossil evidence is lacking for that brief time interval. Here we report the first-known occurrences of in-situ dinosaur and pterosaur remains coincident with the KPg boundary, providing a vantage point that is closer in temporal proximity to the Chicxulub impact than any prior known records for these clades. The fossils, preserved in a Chicxulub impact-triggered surge deposit and mass-death assemblage in the Hell Creek Formation, U.S.A., consist of a well-developed semi-articulated prenatal pterosaur in ovum and partially articulated remains of a subadult ornithischian dinosaur (Family Thescelosauridae). Examination via synchrotron rapid scanning X-ray fluorescence (SRS-XRF), scanning electron microscopy (SEM), and traditional light microscopy revealed extensive preservation of soft tissue consisting of distinct signatures of organic residues as well as three-dimensional structure. The pterosaur embryo, which comprises the first known from the Late Cretaceous and the only example thus far from North America, contributes information pivotal to understanding the prenatal development and early ontogeny of these animals from a time interval for which no such data exists. The ornithischian (c.f. Thescelosaurus sp.) dinosaur, which includes a remarkably complete articulated hind limb enclosed within three-dimensional lithified tubercular skin envelope, provides important data regarding the osseous and soft-tissue anatomy of the Thescelosauridae. In addition to contributing invaluable new anatomical and physiological insights, these specimens constitute the first conclusive evidence of the direct participation of pterosaurs and dinosaurs in the terminal-Cretaceous extinction event.
Estimating Aboveground Biomass for Sparse Tree-shrub Mixed Forest Using Muti-scale Optical Remote Sensing data in the Dryland Ecosystem
Authors: Wang Zhihui , Shi Yonglei
Published: March 2022

Sparse mixed forest with trees, shrubs, and green herbaceous vegetation is a typical landscape in the afforestation areas in northwestern China. It is a great challenge to accurately estimate the woody aboveground biomass (AGB) of a sparse mixed forest with heterogeneous woody vegetation types and background types. In this study, a novel woody AGB estimation methodology (VI-AGB model stratified based on herbaceous vegetation coverage) using a combination of Landsat-8, GaoFen-2, and unmanned aerial vehicle (UAV) images was developed. The results show the following: 1) The woody and herbaceous canopy can be accurately identified using the object-based support vector machine (SVM) classification method based on UAV red-green-blue (RGB) images, with an average overall accuracy and kappa coefficient of 93.44% and 0.91, respectively. 2) Compared with the estimation uncertainties of the woody coverage-AGB models without considering the woody vegetation types (RMSE=14.98 t∙ha-1 and rRMSE=96.31%), the woody coverage-AGB models stratified based on five woody species (RMSE=5.82 t∙ha-1 and rRMSE=37.46%) were 61.1% lower. 3) Of the six VIs used in this study, the near-infrared reflectance of pure vegetation (NIRv)-AGB model performed best (RMSE=7.91 t∙ha-1 and rRMSE=50.89%), but its performance was still seriously affected by the heterogeneity of the green herbaceous coverage. The normalized difference moisture index (NDMI)-AGB model was the least sensitive to the background. The stratification-based VI-AGB models considering the herbaceous vegetation coverage derived from GaoFen-2 and UAV images can significantly improve the accuracy of the woody AGB estimated using only Landsat VIs, with the RMSE and rRMSE of 6.6 t∙ha-1 and 42.43% for the stratification-based NIRv-AGB models. High spatial–resolution information derived from UAV and satellite images has a great potential for improving the woody AGB estimated using only Landsat images in sparsely vegetated areas. This study presents a practical method of estimating woody AGB in sparse mixed forest in dryland areas.