bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparing the diurnal cycle of precipitation in models and observations at different spatial scales over China
Authors: Muetzelfeldt Mark , Schiemann Reinhard , Turner Andrew , Klingaman Nicholas , Vidale Pier Luigi
Published: March 2020

Climate models have a long-standing bias in the diurnal cycle of precipitation over land - they produce peak rainfall at local midday, when insolation is at its maximum. As part of the COnvective Scale Modelling In China (COSMIC) project, we investigate this bias over China using high-resolution (13 km) global simulations with the HadGEM3 model. We compare the diurnal cycle of summer precipitation with satellite observations of precipitation from CMORPH. The simulations are run with and without a convection parametrization scheme, as this scheme has been shown to be important for controlling the timing of precipitation. We analyse the amount, frequency and intensity of the precipitation, investigating their diurnal cycle and spatial distribution.

The analysis is performed on a grid-point scale, as well as at larger scales based on the catchment basins across the region. Catchment basins provide a natural way of linking the meteorological precipitation data to the underlying physical geography of the region, in a way which is useful for decision makers and could be used to provide information to hydrological models in the future. We present a simple Python tool for performing the analysis: BAsin-Scale Model Assessment ToolkIt (BASMATI).

In line with previous studies, we find that the simulation performed with parametrized convection produces precipitation over land which peaks too early in the day. The simulation performed with explicit convection generally produces peaks in precipitation which occur later in the day - closer in time to the observed peak. By comparing our results with published work, we find that the presence or absence of a convection parametrization scheme is more important for determining the spatial distribution of the time of peak precipitation than the resolution of the simulations. We present comparisons of precipitation in the simulations and observations performed at grid points and over catchment basins using BASMATI. The catchment basins are chosen based on their size, which allows for the comparison to be done as a function of spatial scale.
P-TRAP - Diffuse phosphorus input to surface waters
Authors: Walter Sylvia , Behrends Thilo ,   P-TRAP team
Published: March 2020

Phosphate (P) as an essential resource for food production is becoming scarce. Its uncontrolled loss from agricultural areas is in conflict with the principles of a circular economy. Enhanced loading of surface waters with P is the main cause for eutrophication and presents a key challenge in meeting the objectives of the EU Water Framework Directive. Understanding and controlling environmental P fluxes therefore is key to target both problems, to develop new methods and approaches to manage environmental P fluxes, and to improve surface water quality.

In March 2019 the EU Marie Sklodowska-Curie Innovative Training Network P-TRAP has been launched. P-TRAP establishes a framework of partners from multiple science and engineering disciplines. Integration of non-academic partners from various stakeholder groups into the P-TRAP consortium paves the way for direct implementation of the acquired knowledge. The project is targeting the diffuse flux of phosphate (P) into surface waters, i.e. the problems of understanding and controlling environmental P fluxes. P-TRAP aims to develop new methods and approaches to trap P in drained agricultural areas and in the sediments of eutrophic lakes. Trapping of P involves the application of iron(Fe)-containing by-products from drinking water treatment. P-TRAP aspires the ideas of a circular economy and aims at recovering the retained P in agricultural systems. Novel microbial technologies will be developed to convert P-loaded Fe-minerals into marketable fertilizers whose suitability will be evaluated. The P-TRAP technologies have in common that they rely on the naturally strong connection between P and Fe and the innovative P-TRAP strategies will be underpinned by process-orientated investigations on the behaviour of P during the transformation of Fe minerals. The latter are key in trapping and recycling of P in agricultural systems and lakes. The poster will present the structure and the planned research of the project, including a first overview of achievements of the first year.
Numerical simulation of the July 2010 meteotsunami on the coast of Portugal: Implications for meteotsunami hazard in the NE Atlantic
Authors: Kim Jihwan , Omira Rachid
Published: March 2020

In the NE Atlantic Ocean, the tsunami hazard is mainly associated to large earthquakes occurring along the Azores-Gibraltar plate boundary, to submarine landslides, or even to the flank collapses in the volcanic Islands. The hazard posed by meteotsunami remains less understood in the region. Yet, the Atlantic coasts of Portugal, Spain and France have experienced at least two meteotsunamis on July 2010 and June 2011. On July 6th and 7th 2010, uncommon sea waves were observed along the coast of Portugal. The Portuguese tide-gauge network recorded the sea-level signals showing tsunami-like waves of heights varying from 0.14 to 0.6 m (crest-to-trough) and of periods in the range of 30 to 60 min. Analysis of both oceanic and atmospheric data
revealed the occurrence of a meteotsunami on the night of July 6th that propagated from Lagos, south, up to Viana de Castelo, north. Here, we present the first investigation of the 2010 meteotsunami that struck the coast of Portugal. We use the atmospheric pressure data to force the sea surface and numerically generate the 2010 meteotsunami. We then simulate the 2010 meteotsunami propagation over high resolution bathymetric models using a validated NLSW code. The comparison of the simulated waveforms with the records shows satisfactory agreement of wave heights and periods in most stations. Taking the 2010 event as a reference of meteotsunamis along the Portuguese coast, we provide an insight on the meteotsunami hazard posed by
events propagating from south to north of the country. This is done by considering a 2D Gaussian shape pressure disturbance that propagates along shelf under varying conditions of speed and incident angle. This allows identifying a number of “hot spots” on the coast of Portugal where the focus of meteotsunami energy is favorable. Our results suggest that meteotsunamis present a real threat on the highly occupied Portuguesecoast and therefore should be considered in tsunami hazard and forecasting strategies of the NE Atlantic countries. This work was supported by the FCT funded project FAST- Development of new forecast skills for meteotsunamis on the Iberian shelf (PTDC/CTA-MET/32004/2017).
Sentinel-5 Precursor methane and carbon monoxide column retrievals and assessments related to localized emission sources
Authors: Buchwitz Michael , Schneising Oliver , Noel Stefan , Reuter Maximilian , Vanselow Steffen , Bovensmann Heinrich , Burrows John P.
Published: March 2020

The Sentinel-5 Precursor (S-5P) spectral radiance measurements in the shortwave-infrared (SWIR) spectral region permit the retrieval of atmospheric methane (CH4) and carbon monoxide (CO) columns with high spatial resolution and nearly daily coverage. Methane is an important greenhouse gas with increasing atmospheric concentrations contributing to global warming. Carbon monoxide is an air pollutant with emissions originating from, for example, fossil fuel combustion and biomass burning. We have adjusted and optimized the scientific retrieval algorithm WFM-DOAS to retrieve methane and carbon monoxide columns and column-averaged mixing ratios (XCH4 and XCO) from the S-5P spectra. The retrieval algorithm is based on linear-least squares fitting simulated radiance spectra to the observed spectra. For each single ground pixel we determine a quality flag using a Random Forest based machine learning approach and a similar method is also used to bias correct the retrieved methane columns to enhance the accuracy. We present an overview of the WFM-DOAS retrieval algorithm and resulting initial methane and carbon monoxide scientific data products covering the first two years of the S-5P mission including validation and comparisons with the operational data products. We focus on methane and present details on scenes showing elevated atmospheric concentrations originating from localized emission sources. In particular, we present first results from a method developed to automatically identify methane enhancements originating from localized gas, oil and coal emission sources.
Validation of TROPOMI nadir ozone profile retrievals: Methodology and first results
Authors: Keppens Arno , Hubert Daan , Lambert Jean-Christopher , Compernolle Steven , Verhoelst Tijl , Niemeijer Sander , Fjaeraa Ann Mari , ter Linden Mark , Sneep Maarten , De Haan Johan , Veefkind Pepijn ,   CHEOPS-5p validation team
Published: March 2020

Part of the space segment of EU’s Copernicus Earth Observation programme, the Sentinel-5 Precursor (S5P) mission is dedicated to global and European atmospheric composition measurements of air quality, climate and the stratospheric ozone layer. On board of the S5P early afternoon polar satellite, the imaging spectrometer TROPOMI (TROPOspheric Monitoring Instrument) performs nadir measurements of the Earth radiance within the UV-visible and near-infrared spectral ranges, from which atmospheric ozone profile data are retrieved. Developed at the Royal Netherlands Meteorological Institute (KNMI) and based on the optimal estimation method, TROPOMI’s operational ozone profile retrieval algorithm has recently been upgraded. With respect to early retrieval attempts, accuracy is expected to have improved significantly, also thanks to recent updates of the TROPOMI Level-1b data product. This work reports on the initial validation of the improved TROPOMI height-resolved ozone data in the troposphere and stratosphere, as collected both from the operational S5P Mission Performance Centre/Validation Data Analysis Facility (MPC/VDAF) and from the S5PVT scientific project CHEOPS-5p. Based on the same validation best practices as developed for and applied to heritage sensors like GOME-2, OMI and IASI (Keppens et al., 2015, 2018), the validation methodology relies on the analysis of data retrieval diagnostics – like the averaging kernels’ information content – and on comparisons of TROPOMI data with reference ozone profile measurements. The latter are acquired by ozonesonde, stratospheric lidar, and tropospheric lidar stations performing network operation in the context of WMO's Global Atmosphere Watch and its contributing networks NDACC and SHADOZ. The dependence of TROPOMI’s ozone profile uncertainty on several influence quantities like cloud fraction and measurement parameters like sun and scan angles is examined and discussed. This work concludes with a set of quality indicators enabling users to verify the fitness-for-purpose of the S5P data.
Dynamic groundwater management using Lagrangian coherent structures
Authors: Speetjens Michel , Varghese Stephen
Published: March 2020

Scope is scalar transport in enhanced subsurface flows driven via injection and extraction wells. An important application of this concept is found in groundwater treatment by containment and remediation of polluted groundwater via so-called “permeable reactive treatment zones” (PRTZs) and “permeable reactive barriers” (PRBs). Climate change introduces new challenges to clean and safe water as intrusion of seawater or contaminants into water catchment areas by rising sea levels or changing subsurface flow patterns. This necessitates groundwater management that enables shielding and containment of subsurface water bodies under dynamic conditions. However, this is beyond the above conventional water-treatment technologies; PRTZs and PRBs are namely created through a “screen” of injected reactants, construction of infiltration trenches or establishment of subsurface “ice walls” and thus static and inflexible to unforeseen or changing circumstances.

 

This study explores an in situ processing strategy that relies on the existence of so-called “Lagrangian coherent structures” (LCSs) forming in the fluid trajectories and governing the advective transport in the reservoir. Such LCSs emerge naturally in (subsurface) flow systems and admit rapid and accurate control by the pumping scheme for the wells. Moreover, LCSs are fundamentally embedded in the transport of scalar quantities (e.g. reactants or heat) even in case of significant diffusion and/or chemical reactivity. Thus LCSs act as “internal actuators” for scalar transport and can be utilized for the creation of dynamic processing zones, reaction fronts and transport barriers in a wide range of operating conditions. LCS-based in situ processing may offer a promising alternative to conventional methods for groundwater management by enabling dynamic shielding and containment of subsurface water bodies without the need for physical (and static) boundaries as in PRTZs and PRBs.

 

The concept of dynamic in situ processing using LCSs is demonstrated by the advective-diffusive scalar transport in a two-dimensional (2D) unsteady Darcy flow in a circular reservoir driven by an array of injection/extraction wells. To this end the non-trivial link between scalar and Lagrangian transport is rigorously established via methods from dynamical-systems theory. This enables systematic demarcation and characterization of confinement zones and transport barriers as a function of (dynamic) operating conditions for the generic case of scalar transport subject to diffusion.
Forecasting the Dst index from L5 in-situ data using PREDSTORM: accuracy and applicability
Authors: Bailey Rachel , Moestl Christian , Reiss Martin , Weiss Andreas , Amerstorfer Ute , Amerstorfer Tanja , Hinterreiter Juergen , Bauer Maike
Published: March 2020

STEREO-B and STEREO-A are both important proxies for potential solar wind monitors at the Sun-Earth L5 point. In this study, measurements from STEREO-B are used to determine how well the Dst index in particular can be predicted using data measured near the L5 point. This is useful for determining the geoeffectivity of storms resulting from high-speed solar wind streams. Observed solar wind speeds are first mapped to the near-Earth environment as if they had been measured at L1, and the Dst is predicted from the data using a solar wind-to-Dst model. We find that Dst predicted from L5 data performs better than a recurrence model assuming the solar wind conditions repeat every 27 days, although not as well as when predicted from L1 data. The newly developed approach is currently implemented in the PREDSTORM software package to provide a real-time Dst forecast using STEREO-A data.
Utilizing the road bed for combined ground source heating and sustainable rainwater drainage in Hedensted, Denmark
Authors: Andersen Theis Raaschou , Tordrup Karl Woldum , Poulsen Søren Erbs
Published: March 2020

We present a novel climate adaption technology – the Climate Road - that combines collective, ground source heat pump (GSHP) based heating with sustainable urban drainage of rain water (SUDS). The system utilizes the road bed simultaneously as a retarding basin for excess rain water and as the energy source for a GSHP. Surface water percolates through the permeable road paving and is retained in the gravel road bed during extreme precipitation events where the sewage system is often overloaded. Water is subsequently released once capacity is available again on the sewage network. In addition, geothermal piping is embedded in the roadbed, serving as the collector for individual GSHPs that supply connected households with heating. The primary benefit of the combined system is the saved digging costs and lost property value from establishing a separate rainwater basin and trench for the geothermal piping as the road bed is to be established under any circumstances. However, there is also a subtle yet positive effect on the performance of the GSHP, from constantly watering the geothermal piping.

We have constructed 50 m of Climate Road in Hedensted, Denmark. The road bed is 1 m deep and 8 m wide and can retain a maximum of 150 mm of precipitation, given that the catchment area is twice that of the road surface. Moreover, the road bed is hydraulically disconnected from the surrounding soil by means of bentonite mats, to prevent seepage of groundwater into the road bed. Water is discharged by drainage pipes to a nearby rainwater basin for experimental and practical purposes only. 800 m of geothermal piping is embedded in the road bed, supplying a nearby kindergarten with domestic hot water and room heating by means of a GSHP. The Climate Road is fully instrumented with temperature sensors in the road bed, flow meters to measure water discharge and energy metering on the GSHP. We present the performance of the Climate Road in terms of supplied heating and the coefficient of performance (COP) for the heat pump in addition to drained water volumes for the first year of operation.
Transient Response of Atlantic Heat and Freshwater Transports in Future Climate Scenarios
Authors: Mecking Jennifer , Drijfhout Sybren
Published: March 2020

Ocean heat and freshwater transports play an important role in today’s climate system.  The Atlantic meridional heat transport transports 1.2 PW of heat northward leading to the warm climate we experience in Europe today, while the freshwater transport due to the Atlantic Meridional Overturning Circulation (AMOC) is often used as an indicator for the stability of the AMOC.  Future climate projections show that the AMOC is expected to weaken over the next several decades.  These changes to the AMOC as well as other circulations changes will not only impact the heat and freshwater transports in the Atlantic but also the temperature and salinity structure.  Using both CMIP5 and CMIP6 data this study untangles the impacts of velocity changes versus temperature/ salinity in future climate projections on Atlantic heat and freshwater transports.  Initial results show that changes in velocity dominate heat transport changes while the changes in salinity structure play a large role in freshwater transports with the impact of velocity changes being latitude and model dependent.
Large-scale tests to investigate MgO concrete with a long-term stable 3-1-8 phase in the Sondershausen and Teutschenthal mines
Authors: Aurich Jan , Freyer Daniela , Gruner Matthias , Kudla Wolfram
Published: March 2020

These abstract bases on the R & D project ELSA Phase II - Concept development for shaft seals and testing of sealing elements for HAW repositories, funded by the German Federal Ministry of Energy and Economic Affairs.

The installation of sealing elements in salt rock requires a mechanical support system, which is chemical compatible with the host rock. In future HAW-repositories abutments and sealing elements within the shafts and drifts could be made of magnesia building material with the long term stable 3-1-8 binder phase, if solution containing magnesium can attack the seal.

In 2014 a first large-scale experiment was performed in the Sondershausen salt mine in Germany. A vertical borehole with the depth of two meters and a diameter of 1.1 meter was filled with the magnesia-based concrete. Several sensors measured the development of temperature, comprehensive stress and expansion within the test construction for approximately one year. During the binding reaction the temperature increased by 55 K in the center. After 150 days, the expansion in axial direction reached 2.4 mm/m and 1.1 mm/m in radial direction.

In 2018 a second large-scale-experiment was performed in the Teutschenthal salt mine, Germany to continue the investigations. A new vertical borehole with the depth of 3.5 meters and a diameter of 1.3 meters was filled with the same material. The temperature in the center increased by 40 K during the binding reaction and decreased down to the ambient temperature after 20 days. In result of the first experiences, the stress sensor range was increased. After one year a comprehensive stress of 6.2 MPa was measured at the contour and is still evolving at this point (early 2020). The maximum axial expansion reached 7.9 mm/m and stays at this level. The maximum radial expansion reached 0.7 mm/m 20 days after concreting and decreased subsequently. This material behavior corresponds to the high comprehensive stress level.

The second experiment is equipped with a pressure chamber at the bottom. A first determination of the integral gas permeability revealed a value of approx. 3E-18 m² to 3E-17 m². In the near term a multistage pressurization of the construction is planned, using a saturated NaCl solution to evaluate the sealing ability.

This contribution reports on the measured parameters (temperature, stress, strain) of the two large-scale tests with long-term stable MgO-concrete and the composition requirements to obtain a long-term stable MgO concrete. Long-term stable MgO concrete with 3-1-8 phase has been used for the first time in these tests. The measured test-results are the foundation for modelling the behaviour of the MgO-concrete.
The causes of sea-level rise since 1900
Authors: Frederikse Thomas , Landerer Felix , Caron Lambert , Adhikari Surendra , Parkes David , Humphrey Vincent , Dangendorf Sönke , Hogarth Peter , Zanna Laure , Cheng Lijing , Wu Yun-Chao
Published: March 2020

Global-mean sea level (GMSL) has been rising unsteadily by about 1.5 mm/yr since 1900, but the underlying causes of this trend and the multi-decadal variations are still poorly understood. Over the last few years, updated estimates of the underlying contributing processes have become available, notably for the contributions from glaciers, terrestrial water storage, the Greenland Ice Sheet, and thermal expansion. In parallel, 20th-century GMSL estimates have been revised downward as a result of improved reconstruction approaches, spatial bias correction schemes, and the inclusion of estimates of local vertical land motion at tide-gauge locations. Together, both developments now necessitate the re-evaluation of the GMSL budget to determine whether the observed sea-level rise since 1900 can be reconciled with the estimated sum of contributing processes. 

Here we present a probabilistic framework to reconstruct and budget sea level with independent observations considering their inherent uncertainties. We find that the sum of thermal expansion, ice-mass loss and terrestrial water storage changes is consistent with the trends and multi-decadal variability in observed sea level on both global and basin scales, which we reconstruct from tide-gauge records. 

Glacier-dominated cryospheric mass loss has caused twice as much sea-level rise as thermal expansion since 1900. Glacier and Greenland Ice Sheet mass loss well explains the high rates typically seen in global sea-level reconstructions during the 1930s, while a sharp increase in water impoundment by artificial reservoirs has been the dominant contributor to lower-than-average rates during the 1970s. The acceleration since the 1970s is caused by both thermal expansion and increased Greenland mass loss. No additional large-scale deep ocean warming or additional mass loss from Antarctica are needed to explain 20th-century changes in global-mean sea level. This assessment reconciles the magnitude of observed global-mean sea-level rise since 1900 with estimates of underlying processes.
Limits on nature-based solutions for coastal adaptation based on climate change indicators
Authors: Martyr-Koller Rosanne , Lissner Tabea , Schleussner Carl-Friedrich
Published: March 2020

Climate impacts increase with higher warming and evidence is mounting that impacts increase strongly above 1.5°C. Therefore, adaptation needs also rise substantially at higher warming levels. Further, limits to adaptation will be reached above 1.5°C and loss and damage will be inferred. Coastal Nature-based Solutions (NbS) have arisen as popular adaptation options, particularly for coastal developing economies and Small Island Developing States (SIDS), because of their lower overall costs compared to traditional grey infrastructure approaches such as seawalls and levees; their economic co-benefits through positive effects on sectors such as tourism and fisheries; and a broader desire to shift toward so-called blue economies. Two NbS of particular interest for coastal protection are: 1) coral reefs, which reduce coastal erosion and flooding through wave attenuation; and 2) mangroves, which provide protection from storms, tsunamis and coastal erosion. Although there is international enthusiasm to implement these solutions, there is limited understanding of the future viability of these ecosystems, particularly in their capacities as coastal adaptation service providers, in a warmer world.

In this presentation, we highlight how long and with how much coverage coral and mangrove ecosystems can provide coastal protection services for future climate scenarios, using air temperature and sea level rise as climate change indicators. A mathematical model for each ecosystem is developed, based on the physical parameters necessary for the sustainability of these ecosystems. We investigate the protective capabilities of each ecosystem under warming and sea level rise scenarios compatible with: below 1.5°C warming; below 2°C warming; warming based on current global commitments to carbon emissions reductions (3-3.5°C); and with no carbon mitigation (6°C). Results show what temperature and sea level rise values beyond which these ecosystems can no longer provide coastal protective services. These results have also been framed in a temporal window to show when these services may not be feasible, beyond which more costly adaptation measures and/or loss and damage may be incurred.
Detecting groundwater anthropogenic extraction with cyclicity results of wavelet models
Authors: Naranjo-Fernández Nuria , Guardiola-Albert Carolina , Aguilera Héctor , Fernandez-Ayuso Ana , Montero-González Esperanza
Published: March 2020

Groundwater is the main water source for irrigation in arid and semi-arid areas. Unfortunately, it has been proven very difficult to prevent unauthorized extractions. The present work studies the application of wavelet analysis to detect and quantify the unfavorable effects of these extractions on the piezometry.

Wavelets have been widely applied for hydrologic time series analysis since the 1990s, with increasing popularity in recent years. This method can be applied to hydrologic series to reveal complex hydrological processes and evaluate complex latent factors, such as seasonal crop irrigation, controlling groundwater level ﬂuctuations.

Records of the piezometric level from more than 150 piezometers were studied from 1975 to 2016 in the Almonte-Marismas aquifer (SW Spain). The majority of these time series presented periodicities between 11-12 months, which corresponded to hydrological cycles of recharge and discharge. Nevertheless, in some areas close to crop fields, periodicities of 2-3 and 4-6 months have been detected. In these cases, wavelet analysis could be used as a tool to prevent damage in areas in need of deeper legal control.
Simulation studies on single-satellite space ties and their potential to achieve the Global Geodetic Observing System goals.
Authors: Schreiner Patrick , Mammadaliyev Nicat , Glaser Susanne , Koenig Rolf , Neumayer Karl Hans , Schuh Harald
Published: March 2020

The German Research Foundation (DFG) project GGOS-SIM-2, successor of project GGOS-SIM, is a collaboration between the Helmholtz Center Potsdam - German Research Center for Geosciences (GFZ) and the Technische Universität Berlin (TUB). The project aims at investigating the feasibility of meeting the requirements specified by the Global Geodetic Observing System (GGOS) for a global terrestrial reference frame (TRF) with the help of simulations. In GGOS-SIM-2 the potential of so-called space ties is examined in relation to the GGOS targets, 1 mm accuracy in position and 1 mm / decade long-term stability, which have not yet been achieved by the recent International Terrestrial Reference Frame (ITRF). Space ties are provided by a satellite that carries two, three or all the four main space-geodetic techniques, i.e. DORIS, GPS, SLR and VLBI. This allows for a quantification of the impact of systematic errors on the derived orbits and subsequent results of the dynamic method as the TRF. Proposed co-location in space missions such as GRASP and E-GRASP anticipate such a scenario. We therefor simulate the space-geodetic observations based on Precise Orbit Determination (POD) with real observations from various missions and evaluate their potential for determining a TRF. So far, we simulated DORIS and SLR observations to six orbit scenarios, including a GRASP-like and an E-GRASP-like one, and generated TRFs based on each scenario either technique-wise or combined via the space-ties or in combination with ground data. We quantify the effect on the TRF in terms of changes of origin and scale and of formal errors of the ground station coordinates and of the Earth rotation parameters.
Comparison of mega-heatwaves in preindustrial and present-day simulations over Europe
Authors: Shin Jongsoo , An Soon-Il
Published: March 2020

Heatwaves are likely to occur more frequent, longer, and stronger due to the rise in CO2 concentrations. It is related to the change in the mean of a climate distribution, as well as through the change in variance. Mega-heatwaves, in particular, have a crucial impact on human health. Many studies are trying to understand the mechanisms of mega-heatwaves and also their characteristics included amplitude, duration, frequency. In spite of these efforts, researches are limited because of the small number of mega-heatwaves. In order to overcome these limitations, Earth system model should be needed. This study aims to figure out the comprehensive characteristics of mega-heatwaves using Community Earth System Model (CESM). First, the possibility of the occurrence of mega-heatwaves in preindustrial period in Europe was analyzed. Second, the relation between decadal climate variabilities and mega-heatwaves was investigated. In addition, changes in characteristics of mega-heatwaves were compared between preindustrial and present-day simulations.
New paleomagnetic data for Ochotsk-Chukotka volcanic belt
Authors: Lebedev Ivan , Usanova Olesya , Fadeeva Tanya , Lhuillier Florian , Eid Baha , Murray-Bergquist Louisa , Pasenko Alexander , Gavrushkin Dmitriy
Published: March 2020

The Okhotsk-Chukotka volcanic belt (OChVB),  located in the north-eastern part of Russia, is a unique volcanic structure, which has been formed over a wide time interval from Aptian (K1) to Cenomanian (K2) [Tihomirov, 2018]. Age of its formation nearly coincides with the occurrence of the Cretaceous geomagnetic superchron of normal polarity. Thus, the volcanic formations of the OChVB represent a promising object to study the characteristics of the geomagnetic field during the Cretaceous superchron (direction, paleointensity, secular variations) needed to test various models explaining superchrons’s existence .

During the reconnaissance field work of the summer 2019 we have sampled volcanic rocks in 9 sections each includes from 8 to 30 sites corresponding either to lava flow or to tuff layers.

Up to date we have carried out AF demagnetization, petromagnetic and AMS studies. Demagnetisations studies demonstrate that the rocks contain paleomagnetic record of the ancient (primary?) magnetization of good to excellent quality. Petromagnetic experiments indicate that the main magnetic mineral in majority of studied volcanics is titanomagnetite with pseudo-single domain grain size. We use the magnetic fabric derived from AMS studies to test either the modern attitude (slight dipping up to 10-15˚) of studied rocks is due to primary paleorelief or the rocks have experienced some tectonic deformations.
Landslide dam susceptibility in the Austrian Alps inferred from modelled landslides, potential valley damming and lake formation
Authors: Argentin Anne-Laure , Prasicek Günther , Robl Jörg , Hölbling Daniel , Abad Lorena , Dabiri Zahra
Published: March 2020

In mountain landscapes, landslides often block river courses. Although landslides are well-known threats, the risks imposed by landslide dams are sometimes neglected. The impeding of a river can lead to the submergence of parts of the upstream valley and a failure of the dam can flood downstream terrain in a catastrophic event.

Our aim is two-fold: we are interested in creating a landslide dam susceptibility map relying on modelled landslides and resulting damming of valleys and formation of lakes, and in studying the relation between the occurrence of landslide dams and lithology.

Landslide susceptibility maps are a common tool for natural hazard mitigation, but landslide dam susceptibility maps are rarely produced. Several simple indices (Blockage Index, Backstow Index) have been developed to predict the obstruction capacity and stability of landslides on a river from landslide and catchment characteristics (landslide volume, catchment area, dam height etc.). However, those methods were applied on observed landslides, and did not consider landslide susceptibility. Here, we created a first modelling-based landslide dam susceptibility map and compared it to the results provided by the indices.

Although the relation between lithology and landsliding has been thoroughly studied, no connection with dam formation has been highlighted so far. Lithology has an impact on various characteristics of the landslide, including its volume, and also influences valley geometry. We investigated if some alpine lithological units are more prone to landslide dam formation than others.

In our modelling approach we used a 10 m DEM of the Austrian Alps and stochastically triggered landslides based on slope thresholds. We then simulated the runout of the landslides using a fluid flow solver. For each landslide deposit we computed the maximum dammed volume by filling the landslide-dammed DEM, and compared those volumes to the lithology. We also tested the different theoretical geomorphological indices to predict the impounding of the river and compared them to the actual results provided by our method.
Abundance and distribution of microplastics in water and sediments of the river Elbe, Germany
Authors: Stock Friederike , Weber Annkatrin , Scherer Christian , Kochleus Christian , Dierkes Georg , Wagner Martin , Brennholt Nicole , Reifferscheid Georg
Published: March 2020

Plastic pollution in the aquatic environment has gained worldwide attention in the last years. Microplastics have been investigated for over 45 years especially in the marine environment, but only in the past years research has also started to focus on freshwater environments. In the frame of the project about macro- and microplastics in German rivers, samples from 11 sites from the German part of the river Elbe were taken in order to study the plastic pollution in water and sediment, detect sinks of microplastics and better understand transport mechanisms.

The sediment samples were taken with a Van-Veen-grabber, the water samples from the Elbe with an Apstein plankton net (mesh size 150 µm) from the same location. The sediment samples were presorted with wet sieving, organic digestion and density separation and filtered on aluminium oxide filters. For the water samples, the organic matter was digested using a reagent composed of equal volumes of 10 M KOH and 30 % H2O2, then, the microplastic particles were isolated from remaining matrix by density floatation using 1.6 g/mL potassium formate solution and pressure filtration. Analysis was done by visual inspection, selected particles measured with Fourier-transform infrared spectroscopy and masses calculated with a pyrolysis GC-MS.

The results of the sediments of the Elbe reveal that tentative microplastic concentrations differed intensively between the different river compartments. Microplastics in the sediments were in average 600,000-fold higher than in the water samples (when referring to the same volume). The amount of particles also varies significantly between the sampling sites. In sediment samples, microplastic concentrations decreased downstream, in water samples, concentrations varied stronger. The form of the particles is also site specific. In two samples, more than 80% spheres were counted whereas the 6 locations downstream reveal an increase in fragments. Polymer distribution differed between the water and sediment phase with mostly PE and PP in the water samples and a more diverse distribution in the sediments.
Therapeutic and inclusive organic horticulture: an University-society collaborative learning experience
Authors: Labrador Juana , Pérez Aída , Moreno Marta M. , Pérez-Vera Francisco
Published: March 2020

Therapeutic horticulture is a discipline which belongs to both society and health sciences that has its own identity, which differentiates it from others. It arises as a result of the complementary fusion of two disciplines: horticulture and therapy or rehabilitation. In the therapeutic field, it incorporates some knowledges about physical, cognitive and sensory disabilities, different pathologies, psychosocial problems and special needs. Around horticulture, it allows us to develop knowledge about agriculture, gardening, landscaping, environment and others. It has been used, for educational and socialization purposes, for more than half a century, since then with great implantation and recognition in many countries.

The implementation of an organic garden with pedagogical purposes for students of Agroecology in the School of Agricultural Engineering of the University of Extremadura (Spain), has been the scene for the realization of a collaborative project of integrative - teaching - learning strategy between the University and the “Sorapán de Rieros” Foundation. This project has allowed the use of the ecological orchard created for pedagogical purposes based on the needs of students with mental disorders of different nature with whom the Foundation works, connecting then different points of view.

The specialized training in Permaculture, Organic Agriculture and Agroecology, the tutoring work with specific methodologies developed by the expert staff of the Foundation in Psychology and Psychiatry, as well as the coexistence with the University students has been an enriching experience, with enormously satisfactory results in the improvement of mental and physical health, as well as the labor integration of the Foundation students.

Keywords: Therapeutic horticulture, inclusive horticulture, mental health, organic farming, permaculture.
Using reflectance spectroscopy for detecting land-use effects on soil quality in drylands
Authors: Levi Nathan , Karnieli Arnon , Paz-Kagan Tarin
Published: March 2020

The rapid growth in the global population over the past few decades has resulted in the transformation of many natural ecosystems into human-dominated ones. Land-use (LU) dynamics are accompanied by an increase in resource exploitation, often causing deteriorated environmental conditions that are reflected in the soil quality. Soil quality differences between LUs can be observed and measured using near-infrared reflectance spectroscopy (NIRS) methods. The research goal was to apply, measure, and evaluate soil properties based solely on the spectral differences between both natural and human-dominated LU practices, in the dryland environment of the central Negev Desert, Israel. This goal was achieved through the development and implementation of chemometrics techniques that were generated from soil point spectroscopy. Soil quality index (SQI) values, based on 14 physical, biological, and chemical soil properties, were quantified and compared between LUs and geographical units across the study area. Laboratory spectral measurements of soil samples were applied. Significant differences in SQI values were found between the geographical units. The statistical and mathematical methods for evaluating the soil properties’ spectral differences included principal component analysis (PCA), partial least squares-regression (PLS-R), and partial least squares-discriminant analysis (PLS-DA). Correlations between predicted spectral values and measured soil properties and SQI were calculated using PLS-R and evaluated by the coefficient of determination (R2), the Root Mean Square Error of Calibration, and Cross-Validation (RMSEC and RMSECV), and the ratio of performance to deviation (RPD). The PLS-R managed to produce “excellent” and “good” prediction values for some of the soil properties, including EC, Cl, Na, Ca + Mg, SAR, NO3, P, and SOM. Results of the PLS-R model for SQI are R2 = 0.90, RPD = 2.46, RMSEC = 0.034, and RMSECV = 0.057. The PLS-DA classification of the laboratory spectroscopy was applied and resulted in high accuracy and kappa coefficient values when comparing LUs. In contrast, comparing the sampling sites resulted in lower overall accuracy (Acc = 0.82) and kappa values (Kc = 0.80). It is concluded that differentiation between physical, biological, and chemical soil properties, based on their spectral differences, is the key feature in the successful results for recognizing and characterizing various soil processes in an integrative approach.  The results prove that soil quality and most soil properties can be successfully monitored and evaluated using NIRS in a comprehensive, non-destructive, time- and cost-efficient method.
Mapping the dynamics of the Lagunas de Ruidera wetland (Spain) using remote sensing
Authors: Pardo-Iguzquiza Eulogio , Pulido-Velazquez David , Collados-Lara Antonio-Juan , Baena-Ruiz Leticia
Published: March 2020

Wetlands protect and improve water quality, store floods, maintain surface water during dry periods and provide valuable habitats for wildlife. However, wetlands may be very sensitive to climate change and appropriate monitoring works and modelling activities are needed in order to design sustainable management strategies. In this work we aim to analyze the dynamics of the Lagunas de Ruidera wetland (Spain) for the period 1984−2015. We applied the supervised classification method to LANDSAT satellite images (missions 5, 7 and 8) with a spatial resolution of 30 m and a temporal resolution of around 16 days. In this case study two different water bodies in terms of surface reflectance have been detected. Both zones have been considered for the calibration of the water detection algorithm through a non-steady threshold. We have also analysed daily surface reflectance data from MODIS (MOD09GQ) to complete the temporal dynamic of the wetland. We obtained some correlations between surface reflectance of LANDSAT and MODIS but the efficiency to detect water surfaces of the second is considerably lower due to its 250 m spatial resolution. The results show a minimum and a maximum wetland surface of around 2.7 and 6.3 km² for the considered period. We have also analysed the relationship of the wetland surface with precipitation and aquifer discharge (obtained from a groundwater flow model). For the mean year at monthly scale, the maximum correlation between the wetland surface and precipitation is obtained for a lag of one month. The wetland surface has a similar monthly trend to the aquifer discharge and the maximum correlation is obtained without lag.

This research has been partially supported by the SIGLO-AN project (RTI2018-101397-B-I00) from the Spanish Ministry of Science, Innovation and Universities (Programa Estatal de I+D+I orientada a los Retos de la Sociedad) and by the GeoE.171.008-TACTIC project from GeoERA organization funded by European Union’s Horizon 2020 research and innovation program.
Time and tempo of melt segregation from a magma mush: evidence from the Takidani pluton (Japan)
Authors: Farina Federico , Rubatto Daniela , Hartung Eva , Caricchi Luca
Published: March 2020

The Takidani pluton is a Pleistocene intrusion representing a nearly 2 km-thick shallow level magma reservoir located in the Central Japan Alps. The pluton, which is associated with caldera-forming eruptions, is vertically zoned and composed of six distinct lithological units ranging from hornblende-bearing granodiorite to biotite granite, with silica content varying from ca. 65 to 76 wt.%. In its upper part, the intrusion is characterized by the gradual transition between equigranular and porphyritic granodiorites. Textural and geochemical evidence indicates that the porphyritic unit represents a lens of residual melt extracted from the underlying equigranular granodiorite (Hartung et al., 2017).

The time and tempo of melt extraction is determined using both high precision and high-spatial resolution U-Pb zircon geochronology, performed by CA-ID-TIMS and SIMS respectively. High precision 206Pb/238U zircon ages for the two units are similar, with grains from both rocks exhibiting an age spread as large as 200-300 kyr, from ca. 1.2 to 1.5 Ma. In-situ U-Pb dating obtained by SIMS using a spot size of 20 μm reveal systematic age difference between cores and rims, highlighting two events of zircon crystallization with no substantial difference between the two units. Zircon cores from the porphyritic and equigranular granodiorites give identical ages at ca. 1.45 ± 0.06 Ma. Spot U-Pb ages from magmatic rims range between 1.29 and 1.07 Ma, with a peak of the distribution density at around 1.20 Ma.

This information, combined with Zr saturation temperatures and phase equilibria modelling, suggests that zircon cores crystallized from the magma reservoir before rheological locking and melt segregation were achieved. The segregation of the interstitial melt from the mush took place in the ca. 250 kyr between the two events of zircon crystallization. The extracted residual melt was depleted in Zr and carried entrained crystals of plagioclase and zircon from the mush. The low Zr content of this melt hindered zircon crystallization that was only possible after a time lag of 250 kyr. The youngest event of zircon crystallization at ca. 1.2 Ma was contemporaneous in the segregated melt and in the underlying mush.

 

Reference: Hartung, E., Caricchi, L., Floess, D., Wallis, S., Harayama, S., Kouzmanov, K., Chiaradia, M., 2017. Evidence for residual melt extraction in the Takidani Pluton, Central Japan. J. Petrol.58, 763–788.
Added seasonal forecasting skill from land surface parameterization detail
Authors: van den Hurk Bart , Hurkmans Ruud , Wetterhal Fredrik , Pechlivanidis Ilias , Weerts Albrecht
Published: March 2020

During dry spells, a large part of the Netherlands depends on water from the IJssel lake, a large surface water reservoir. Water is extracted for a number of purposes, such as irrigation, water quality, shipping and drinking water. Besides local precipitation, the main source of water flowing into the lake is the river IJssel; a distributary of the Rhine. To keep water available for extraction by the surrounding regions, lake levels cannot be allowed to fall more than about 20 cm under the regular summer maintenance level. Prior to the onset of a drought, therefore, it might be desirable to raise lake levels to maintain sufficient water availability during the dry spell. For adequate management of the reservoir, therefore, long-range forecasting of precipitation and river discharge would be extremely helpful. However, meteorological forecast skill is known to be nearly absent for lead times longer than about a month in northwestern Europe. The land surface contains a number of components that may increase forecast skill for Rhine river discharge; examples are the amount of snow in the Alps, groundwater, and soil moisture. We investigate to what extent this is the case and whether the forecast skill of Rhine river discharge forecasts increases with increasing detail in the land surface parameterization of the initial conditions. We collected streamflow reforecasts from various sources: ECMWF SEAS5, EFAS, SMHI-HYPE and a high-resolution distributed hydrological model (WFLOW), forced by ECMWF SEAS5 meteorological forecasts.