bluuebunny/crossref_metadata_2025 huggingface dataset:
The response of intense Mediterranean cyclones to climate change 
Authors: Alvarez-Castro M. Carmen , Gualdi Silvio , Faranda Davide , Ribera Pedro , Gallego David , Peña-Ortiz Cristina
Published: March 2022

Intense Mediterranean cyclones (IMC) are weather systems that have a high potential for destruction in the densely populated coastal areas around the Mediterranean sea and they cause high risk situations, such as flash floods and large-scale floods with significant impacts on human life and built environment. The aim of the study is to analyse and attribute future changes in IMC under different future forcings and to assess the effect of horizontal model resolution by comparing hydrostatic- versus convection-permitting models. Following a non-linear approach, we explore IMC events that are connected to anomalous atmospheric patterns. First, the analogs search is performed on ERA5 and historical simulations, so as to use the latter as a control run for future projections.  We then examine clusters and trends in the dates of analogs and study their predictability properties in the attractor space (e.g., local dimension and persistence). Then we explore how the trajectories of the precursors of the observed extreme event, emerging from the analog approach, may eventually lead to an IMC event in each available simulation. In this way, we can evaluate the probability of obtaining an observed event, given an initial condition. Finally, we evaluate the physical factors possibly connected to the change of probability of the event.
Macro-Turbulent Energy Cascades in UpperTropospheric-Lower Stratospheric Mesoscales
Authors: Can Serhat
Published: March 2022

In recent years a consensus has been reached regarding the direction of the energy cascade in the mesoscales in the Upper Tropospheric-Lower Stratospheric (UTLS) altitudes. Numerous measurements and model results confirm the existence of a predominantly forward spectral energy flux from low to high horizontal wavenumbers. However, the details to explain the observed -5/3 power law for Kinetic and Available Potential Energy (KE and APE) are still being debated.

In this study we performed simulations using the dry version of the Kühlungsborn Mechanistic general Circulation Model (KMCM) with high horizontal and vertical resolution for permanent January conditions. Horizontal diffusion schemes for horizontal momentum and sensible heat satisfy the Scale Invariance Criterion (SIC) using the Dynamic Smagorinsky Model (DSM). We investigated the simulated KE and APE spectra with regard to the scaling laws of Stratified Macro-Turbulence (SMT). Zonally and temporally averaged dissipation rates for KE & APE and SMT statistics correlate highly in subtropical mid-latitudes and the UTLS levels. Particularly the characteristic dimensionless numbers of Buoyancy Reynolds Number and turbulent-Rossby Number are pronounced in the regions, where the maximum of the forward spectral fluxes of nonlinear interactions are also found. During this process the spectral contribution of the negative buoyancy production term plays an important role by converting KE to APE. These findings are entirely in line with the spectral and statistical predictions of idealized Stratified Turbulence (ST) and confirms that the energy cascades that give rise to the simulated mesoscale shallowing are strongly nonlinear.

Furthermore level by level analyses of the horizontally averaged spectral tendencies and fluxes of both KE and APE reservoirs in this specific region revealed that there is a non-negligible spectral contribution by the energy deposition term of upward propagating Gravity Waves (GW). Further investigation indicate the dynamics of these resolved GWs look like a superposition of westward Inertia GWs that are subject to a Lindzen-type saturation condition. Their vertical propagation in UTLS heights is non-conservative above their generation level. These results associate directly for the first time ST and GW dynamics, which were thought to be distinct in character. Finally we present simulations with different diffusion schemes and show that the previously mentioned energy deposition contribution was only identified if both horizontal momentum and sensible heat diffusion schemes fulfill the SIC.
Severe cooling of the Atlantic thermocline during the last glacial
Authors: Lausecker Marleen , Hemsing Freya , Krengel Thomas , Förstel Julius , Schröder-Ritzrau Andrea , Border Evan Cooper , Orejas Covadonga , Titschak Jürgen , Wienberg Claudia , Hebbeln Dierk , Wefing Anne-Marie , Montagna Paolo , Douville Eric , Matos Lelia , Raddatz Jacek , Frank Norbert
Published: March 2022

The mean cooling of the global ocean during the Last Glacial Maximum (LGM) was recently estimated to 2.6°C using noble gases trapped in ice cores (1). The ocean, however, is highly heterogeneous with respect to its internal temperature varying both in latitude and water depth. While temperature changes in the deep ocean are small at about 2 - 3 °C (1,2), the upper ocean is more dynamic. Regional temperature anomalies of up to 7°C are predicted during the LGM compared to modern interior ocean temperature by global ocean circulation models (3). Due to the temperature drop to near freezing conditions and the global increase in salinity from ice sheet growth, the oceans’ deep interior became strongly haline stratified (2). Temperatures of the glacial ocean thermocline are, however, less well constrained.

Here, thermocline temperature reconstructions since the last glacial based on the Li/Mg ratio in cold-water coral skeletons are presented. The coral samples, collected from 300 - 1200 m water depths from different sites in the Atlantic (43°N to 25°S), reveal synchronous 5 - 7°C cooling during the last glacial period compared to today, as well as a dramatic shoaling of the thermocline. At the end of the LGM, warming of the upper thermocline ocean occurred early in the southern hemisphere followed by a fluctuating warming and thermocline deepening in the northern Hemisphere. This supports the oceanic climate seesaw proposed by Stocker and Johnson in 2003 (4). We thus propose dramatic changes in the export of polar waters towards the Equator and an enhanced subsurface ocean stratification leading to a mostly polar Atlantic with a shallow permanent thermocline during the glacial.

 

References:

1) Bereiter et al., Nature 553, 39-44 (2018).
2) Adkins et al., Science 298, 1769-1773 (2002).
3) Ballarotta et al., Clim. Past 9, 2669-2686 (2013).
4) Stocker and Johnsen, Paleoceanography 18, 1087 (2003).
Mantle metasomatism recorded upon bimodal chromitites (E. Chalkidiki, Greece): a tool to unravel metasomatic processes
Authors: Koutsovitis Petros , Sideridis Alkiviadis , Tsitsanis Pavlos , Zaccarini Federica , Tsikouras Basilios , Hauzenberger Christoph , Grammatikopoulos Tassos , Bindi Luca , Garuti Giorgio , Hatzipanagiotou Konstantin
Published: March 2022

Nea Roda and Gomati ultramafic bodies (east Chalkidiki, north Greece) consist of both Cr- and Al- podiform chromitites, which are highly altered. Their PGE geochemistry and subsequently PGE-mineralogy (PGM) demonstrate abnormal element concentrations with an enrichment in PPGE (Pd, Pt), leading to high Pd/Ir ratios. Secondary PGM and base metal assemblages are dominated by Sb and As, whereas primary phases form sulphides. At a more mature stage, desulphurization of the aforementioned phases led to formation of native metals. Diopside hosted within diopsidite and chromitite show both an alkaline melt- and a fluid- rock interaction, depicted by LREE enrichment. The temperature of the metasomatic fluids was lower than 600oC, as recorded by chlorite and garnet geothermometry. A raise in fluid mobile elements (FME: B, Sb, Li, As, Cs, Pb, U, Ba and Sr) is noted in the whole rock and clinopyroxene analysis. All these characteristics along with the distinctive spinel textures (porous, zoned grains) point to a metasomatic event during subduction that led to the post-magmatic modification of the chromitites and the mantle section causing a LREE, Pb, As, Sb, Pd and Pt enrichment. 
Modelled and observed stage-discharge relationships for cobble leaky barriers with and without pipes
Authors: Milledge David , Johnson Adam , Allott Tim , Brown David , Edokpa Donald , Evans Martin , Goudarzi Salim , Kay Martin , Rees Joe , Shuttleworth Emma , Spencer Tom
Published: March 2022

Flooding is costly and disruptive in the UK and worldwide. Leaky barriers (LBs), small-scale blockages to streamflow, provide multiple environmental benefits. Depending on design, and if installed in sufficient numbers, they could also play an important role in reducing downstream flooding. Leaky barrier installation is proceeding at pace, thousands of cobble dams have been installed in peat gullies across the South Pennines (UK). However, the hydraulics of LBs in general and these cobble barriers in particular is poorly understood. Here we develop a simple model coupling two classical engineering flux estimates: Darcy/Casagrande equations for matrix flow and Colebrook equation for pipe flow (where drains are installed). We test this model against observed stage and discharge measurements for four study features with and without drains to: identify stage-discharge relationships; evaluate model performance for individual features; and apply it to model chains of features of varying design (i.e., LB density, matrix permeability, and pipe diameter). We find that: 1) stage-discharge relationships for cobble dams are concave up and are generally well captured by our simple model; 2) current designs offer relatively little attenuation because they are too permeable; 3) instead, optimal designs have low matrix permeability with pass-forward pipes at their base of a diameter tuned to design flow. Based on these results we hypothesise that LBs will perform best where they are designed to have negative permeability-depth relationships (and thus convex up stage-discharge relationships) and where the form and magnitude of the relationship is optimised to accommodate peak flood discharges.  
Characterization and nowcasting of severe weather events over Milano Malpensa
Authors: Anesiadou Aikaterini , Chkeir Sandy , Biondi Riccardo
Published: March 2022

Extreme weather events in Europe have increased in frequency and intensity in the last decades, especially in some areas like Alpes and Balkans, and is expected to increase even more in the upcoming years due to the climate change. Monitoring and forecasting the severe weather events locally developed and in a short time range is very challenging but also very important for aviation safety. Several studies have been made for studying the pre-convective environment, however there are still gaps in the knowledge of the dynamical processes of regional and short duration deep convective systems.

This study is implemented within the SESAR ALARM project and focuses on the analysis of the pre-convective and convective environment in support to the air traffic management and air traffic control. The work focuses in the detection, analysis and nowcasting of severe weather events in a selected hotspot: the area of Milano Malpensa airport in Italy. We have used the data from 28 weather stations, 8 GNSS stations, radar and lightning detectors, in the period 2010-2020 to train a nowcasting algorithm and to characterize the pre-convective environment.

Our first results for different locations in the area of interest, show on average that the root mean square error of the rainfall prediction lie in the range 0.1029-0.2838 mm and 0.2720-0.7815 m/s for the wind speed prediction. Our algorithm shows the best rain predictive performance in the next 10 minutes higher than 90%, and higher than 80% in the next 30 minutes. Moreover, the pre-convective environment analysis shows that all the cases with wind field divergence never show an increasing trend of GNSS Zenith Total Delay before the event.
Investigating impacts of large-scale vegetation restoration on water recycling processes in the agro-pastoral ecotone of Northern China
Authors: Wang Xuejin , Zhang Baoqing , Zhang Zhenyu , Kunstmann Harald , He Chansheng
Published: March 2022

From 1998 until now, the Chinese government has implemented numerous policies and programs, such as the Grain for Green Program, the Three-North Shelter Forest Program, and the Beijing-Tianjin Sand Control Program, to restore ecosystems and to improve environmental protection in the agro-pastoral ecotone of Northern China (APENC). However, it remains unclear how the large-scale vegetation restoration modulates the regional moisture cycle in the APENC. To fill this gap, we investigated the variations of observed precipitation and estimated evapotranspiration from 1995 to 2015. The evapotranspiration is estimated by the Priestley-Taylor Jet Propulsion Laboratory model with dynamic vegetation (DV). The precipitation recycling ratio calculated by the Dynamic Recycling Model is used to analyze the impacts of vegetation restoration on regional moisture recycling. Our results show that the precipitation and ET under the DV were significantly increased during the period of 1995-2015, with the increasing rate of 4.42 mm yr-1 and 2.13 mm yr-1, respectively. The precipitation recycling ratio was also significantly increased during the study period, showing positive feedback of vegetation restoration on precipitation. The atmospheric water budget analysis shows that vegetation restoration noticeably modifies the annual mean values of water transport terms in the regional water cycle, indicating an indirect effect on local precipitation. Our findings help better understand the impacts of land cover change on local water resources, which in turn supports local water resource management and decision making.
Pre-Jurassic tectonic evolution of the central part of West Siberian basin: the new data from the Frolov-Krasnoleninsky region
Authors: Latyshev Anton , Panchenko Ivan , Kulikov Petr , Smirnova Maria , Fedyukin Ivan , Gusev Ivan
Published: March 2022

The basement of West Siberian plate has mosaic architecture and consists of the Paleozoic fold belts and supposed Precambrian massifs. The Frolov-Krasnoleninsky region is located in the central part of the West Siberian basin (near the town of Khanty-Mansiysk) and occupies the key position in its structure.  The junction of the Uralian fold belt, Kazakhstan superterrane, and Irtysh-Zaysan fold zone is located there. However, the pre-Jurassic tectonic evolution of this area is still poorly constrained. Based on the new representative data on drill cores from deep boreholes and geophysical data, whole-rock geochemistry and U-Pb ages, we reconstructed the main stages of the geological history of this area:

In the Neoprotertozoic the ancient metamorphic complexes of the Krasnoleninsky and Aprel’sky uplifts were formed. Based on the detrital zircons ages and correlation with similar rocks in the nearby fold belts, we suggest that this stage terminated about 600-540 Ma.

In the Early Paleozoic volcano-terrigenous rocks were accumulated mainly in the island arc tectonic setting. This stage ended with the emplacement of gabbro-granitic plutons, fold deformations and amalgamation of the Kazakhatan superterrane with the Krasnoleninsky block in the beginning of Silurian (446-440 Ma).

In the Devonian – Early Carboniferous carbonate and overlying mainly clastic sediments were accumulated. The first manifestation of supra-subduction volcanic activity and granitic intrusions are identified as Late Devonian-Early Carboniferous. At the end of Early – beginning of Middle Carboniferous fold deformations related to the closing of back-arc basin took place.

In the Middle – Late Carboniferous differentiated volcanic series and coeval granodiorite massifs of the continental arc tectonic setting were formed (310-307 Ma). This stage corresponds to the convergence of continental masses of Siberian and East European platforms and Kazakhstan superterrane and the closing of relic oceanic basins between them.

The Early-Middle Permian is a time of collision, manifested by large granitic plutons in the Krasnoleninsky uplift and other areas of the West Siberia and Uralian fold belt (290-260 Ma). At this stage, main structural features of the basement of West Siberian plate were formed.

In the Late Permian – Early Triassic West Siberia was an area of wide-scale rifting, caused by the post-collisional extension and the mantle plume ascent. Thick sequences of the contrasting basaltic and felsic lavas were erupted. Volcanic piles are overlain by clastic coal-bearing sediments of the Triassic and, possibly, Early Jurassic age.
Deformation observations and geodetic modelling during the recent unrest at Askja volcano
Authors: Parks Michelle , Ófeigsson Benedikt , Drouin Vincent , Sigmundsson Freysteinn , Hooper Andrew , Geirsson Halldór , Hreinsdóttir Sigrún , Friðriksdóttir Hildur , Sturkell Erik , Hjartadóttir Ásta , Lanzi Chiara , Li Siqi , Barsotti Sara , Óladóttir Bergrún
Published: March 2022

At the beginning of August 2021, inflation was detected at Askja volcano, on a continuous GNSS station located to the west of Öskjuvatn and on interferograms generated using data from four separate Sentinel-1 tracks. Ground deformation measurements at Askja commenced in 1966 with levelling observations and since this time additional ground monitoring techniques have been employed, including GNSS and Satellite interferometry (InSAR) to detect long-term changes. Ground levelling measurements undertaken between 1966-1972 revealed alternating periods of deflation and inflation. Measurements from 1983-2020 detailed persistent subsidence of the Askja caldera, initially at an inferred rate of 7 cm/yr, decaying in an exponential manner. Suggested explanations for the long-term subsidence include magma cooling and contraction, or withdrawal of magma – eventually facilitated by an extensive magma-rich plumbing system, with an open conduit between the uppermost and the deeper parts of the magmatic system. This presentation will focus on the recent period of uplift and provide an overview of the GNSS and InSAR observations to date and present the latest geodetic modelling results which describe the best-fit source for the observed deformation.
Development of a solar energy forecasting system for two real solar plants based on WRF Solar with aerosol input and a solar plant model
Authors: Prósper Miguel A. , Sosa-Tinoco Ian , Miguez-Macho Gonzalo
Published: March 2022

Regional meteorological models are becoming a generalized tool for solar energy production forecasting,  due to their capacity to simulate different types of cloud formations and their interaction with solar radiation. The greater demand for reliable forecasting tools in the energy industry is the motivation for the development of an integrated system that combines the Weather Research and Forecasting atmospheric model package designed to fulfill the needs of solar energy applications (WRF-Solar), with the solaR power plant model. This study focuses on the use and validation of this coupled tool in forecasting the energy production for two real solar plants, one in Spain and another in India. A period of one year for the Spanish emplacement and nine months for the Indian site are simulated with a daily operational forecasting set-up. Aerosol data from the Copernicus Atmosphere Monitoring Service (CAMS) are considered in the calculations, a new capability in WRF-Solar. Power predictions are obtained and compared with real data from the inverters of both plants provided by the operating company.

The results show that WRF-Solar obtains accurate forecasts of global, direct, and diffuse radiation and of the ambient temperature that solaR uses as input to predict the energy production of the solar plants. The normalized Mean Annual Errors (NMAE) is 5.18% in the Spanish and 5.59% in the Indian plant for the first day of predictions, demonstrating a reliable performance of the forecasting system in different climate locations. The skill scores for the second day of prediction are also promising, with practically the same errors as the previous day (5.19% and 6.17 for Spain and India respectively). By comparing the model predictions, with and without AOD input during the dustiest days in the Spanish site, the importance of the aerosol effect inclusion is demonstrated with an improvement up to 10% in the energy forecast. These results demonstrate the system’s potential both for solar plant operation and energy market applications.
Grasping water availability at regional scale: development of exploratory methods
Authors: Brakkee Esther , van Huijgevoort Marjolein , Stofberg Sija
Published: March 2022

Climate change and socio-economic development are putting water resources under increasing pressure, even in what are so far seen as ‘water-rich’ countries. At a regional scale, the water resources present in groundwater, soil water and surface water are often used for various functions, including nature, agriculture and drinking water production. Local changes in water management or land cover can potentially affect all these functions. Therefore, ensuring a sustainable water availability requires an integrated understanding of the interactions in the water system. However, regional water systems, that often include a wide range of water pathways and functions, can be complex to grasp and time-intensive to study in detail. There is therefore a need for exploratory methods that provide a fast and comprehensive overview of the interactions in regional water systems. This provides a valuable first step to direct research and management efforts.  

In this study, we have developed an exploratory water system analysis method using a case study in the south of the Netherlands. The case study area supports groundwater-dependent nature areas, agriculture, drinking water production and urban land use, which may face increasing pressure in the future. Several adaptation measures have been proposed, including restoration of natural brook systems, enhancing groundwater recharge and changing extraction regimes. As a first step, we developed quantitative visual overviews of the water system under both average and dry conditions, using a combination of a groundwater model and field data. Next, we used simplified analytical functions to assess the potential effects of several proposed measures on water stores and fluxes in the water system. Together, these analyses provide an overview of the main system drivers and potential threats to water availability. In addition, they help to identify which potential solutions are promising for further exploration. The results can be used to guide further research and cooperation in the area towards a sustainable water system. In addition, the methods can be easily applied to other regions and scales.
Transition from Aegean back-arc extension to Corinth rifting. Miocene to Pleistocene interacting extensional regimes of the Northern Peloponnese. 
Authors: Wicker Vincent , Ford Mary , Gawthorpe Robert , Kranis Haralambos , Skourtsos Emmanuel , Bouilhol Pierre , Muravchik Martin , Fabregas Natacha , Beaufumé Kévin , Beldame Hugo
Published: March 2022

Continental extension is characterized by two end members: rifting and highly extended terrains. These two modes of extension usually develop under very different conditions and are rarely observed together. However, in the northern Peloponnese, metamorphic windows recording Miocene late orogenic to back arc extension of the Southern Hellenides on low angle detachments, lie directly south of the younger Pliocene-Pleistocene Corinth rift and appear to interact with its southern margin fault system. This work integrates data from a recent structural and stratigraphic field campaign from the Central Peloponnese to the Corinth rift southern margin with regional cross-sections to document the style of regional Miocene to Pliocene extensional tectonics and the transition from the wide extensional regime to the narrow Corinth rifting. It shows that the pre-rift Hellenides nappe stack was stretched by about 15-25 km by low angle extensional faults that root into the Cretan detachment that forms the main decoupling level in this area. These low-angle extensional faults contribute to the exhumation of the Quartzite-Phyllite metamorphic nappe and contribute to the continental unroofing of the Southern Hellenides. New field data in the northern Peloponnese indicate that  continental sedimentation controlled by these low angle normal faults underlies in apparent continuity the  Corinth syn-rift succession, which  is itself controlled by later high angle rift faults. We integrate in a regional structural model the transition from the pre-rift Aegean extensional tectonic regime to early-stage Corinth rifting recorded in newly mapped depocenters located in the south-eastern Corinth basin between Stymfalia and Nemea.
Geomagnetic field shielding over the past 100 000 years
Authors: Korte Monika , Gao Jiawei , Panovska Sanja
Published: March 2022

The geomagnetic field prevents energetic particles, such as galactic cosmic rays, from directly interacting with the Earth's atmosphere. The geomagnetic field is not static but constantly changing, and over the last 100,000 years several geomagnetic excursions occurred. During geomagnetic field excursions, the field strength is significantly decreased and the field morphology is controlled by non-dipole components, and more cosmic ray particles can access the Earth's atmosphere. Paleomagnetic field models provide a global view of the long-term geomagnetic field evolution, however, with individual spatial and temporal resolution. Here, we reconstruct the geomagnetic shielding effect over the last 100,000 years by calculating the geomagnetic field cutoff rigidity using four global paleomagnetic field models, i.e., GGF100k, GGFSS70, LSMOD.2, and CALS10k.2. We find that the non-dipole components of the geomagnetic field are not negligible for estimating the long-term geomagnetic shielding effect, in particular during excursions. Our results indicate that cosmic ray flux, impact area, and cosmic ray radiation intensity increase strongly during the excursions. Our results provide the possibility to accurately estimate the cosmogenic isotope production rate and cosmic radiation dose rate covering the last 100,000 years.
Combining green infrastructure and ground heat exchangers in urban areas
Authors: Yildiz Anil , Stirling Ross
Published: March 2022

Ground Source Heat Pump (GSHP) systems are one of the many alternatives that will help to decarbonise the space heating and cooling – especially in residential sector. High capital costs of drilling for borehole heat exchangers and added complexity of space dedication in densely populated urban areas are hindering the market development. We propose combining GSHP systems with Sustainable Drainage Systems (SuDS) for a more efficient heat exchange, which provide opportunities to significantly improve the resilience and sustainability of our built environment. This combined system removes the need to dedicate space to accommodate shallow ground heat exchangers in areas where the unit price of land is high. Furthermore, hydrological conditions prevalent in the substrate of SuDS provide demonstrably beneficial thermo-hydrological interactions. We built an at-scale SuDS component, i.e. a 950-mm high soil column with a diameter of 1800 mm, as a lysimeter setup at the National Green Infrastructure Facility to test the heat injection into the substrate. A range of field testing scenarios (thermal load and cycling) were applied under natural, external ambient conditions. Soil temperature during heat injection was also simulated numerically by solving a transient heat conduction equation with a finite difference modelling scheme. The developed model was validated using measurements from the lysimeter setup which then enabled numerical experiments into the effects of varying hydrological regimes to be performed.
Investigating process drivers of Natural Flood Management and its flood risk reduction potential across scales
Authors: Goudarzi Salim , Milledge David , Holden Joseph , Allott Tim , Edokpa Donald , Evans Martin , Kay Martin , Shuttleworth Emma , Spencer Tom
Published: March 2022

Before-after monitoring of small-scale restoration activities in blanket peatlands, e.g., revegetation and gully blocking, suggests they can also deliver significant Natural Flood Management (NFM) benefits (reduce and delay floodpeaks). However, we still lack a clear understanding of the underlying processes driving NFM effects; and doubts remain about whether interventions will retain their impact when implemented at scales large enough to reduce flooding in downstream communities. We examine the impact of the two interventions at a range of scales from the 1 hectare micro-catchment scale at which a Before-After-Control-Intervention (BACI) study has been undertaken, to the 40 km2 scale (at which flooding begins to affect residential properties). We calibrate the Generalised Multistep Dynamic (GMD) TOPMODEL rainfall-runoff model to different BACI experimental catchments each representing an intervention scenario. Through numerical experimentation with the calibrated parameters, we estimate the impact-magnitude of different process drivers. Our findings confirm the NFM benefits of these restoration-focused interventions at the micro-catchment scale. In both interventions and in our largest storms, floodpeak attenuation is primarily due to roughness reducing the floodwave speed and thus thickening the overland flow (kinematic storage). More conventional, static storage (i.e. interception + ponding + evapotranspiration), becomes important only in smaller storms. Finally, we use the parameter-sets identified by calibrating to the BACI catchments to extend our findings to the 40 km2 Glossop catchment. Glossop has experienced several damaging floods in the last 50 years and has received appreciable recent restoration activity. Here we use GMD-TOPMODEL in a second set of modelling experiments to estimate downstream impact of existing interventions and to examine the impact of alternative scenarios of spatially distributed intervention configurations.
Detection of Habitat Heterogeneity Changes Using Laser Scanning Data Targeting Birds
Authors: Kim Ji Yeon , Lee Dong Kun , Kim Eun Sub
Published: March 2022

Research dealing with three-dimensional structural data of forests or vegetation is increasing. LiDAR-based research to detect biodiversity (LaRue et al. 2019) is growing, through using structural data such as analyzing heterogeneity, distribution, and height in forest structures (Matsuo et al. 2021) or identifying rugosity (Gough et al. 2020). For example, the technology to detect canopy structures is linked with the GEDI technology, leading to structural diversity mapping on a wide scale and further to β-diversity. (Schneider et al. 2020) Meanwhile, most connectivity studies so far have been conducted on two-dimensional surfaces, and resistance value-based studies on species data, topography and vegetation structure, and habitat quality have been performed. In this study, we try to detect changes in the space distribution pattern of species due to anthropogenic intervention through lidar-based 3D structural data. Through structural heterogeneity, the connectivity at the landscape level is analyzed, and for this purpose, it can be compared with the traditional diversity evaluation method through a verification process based on species data. By detecting the impact on species in advance in the impact assessment stage, this study intends to present a methodology that can function as a forestry and conservation decision-making support tool in combination with ICT-based monitoring technology.
Benthic foraminifera community structure; a function of dispersal and environmental gradients 
Authors: Alfaraj Mashaer , Amao Abduljamiu , Alramadan Khalid , Kaminski Michael
Published: March 2022

Research into the resting stage and dispersal of benthic foraminiferal using propagules is helping to reshape our understanding of dispersal and the distribution of benthic foraminifera.  As a result, our understanding of what constitutes a dominant and cryptic species is also changing.  In other words, individual and multi-species assemblages appear to respond differently to one or more specific environmental conditions. This, in turn, is responsible for the noticeable changes or lack of, in a community structure. In the current study, we investigated the community structure of benthic foraminifera retrieved from samples collected from three locations in Eleuthera Island, Bahamas to understand the similarities and differences in the assemblage composition and structure. Our main undelaying assumption is that, given the three locations are spatially connected and receive a similar load of propagules, they should be similar compositionally without any other influences. However, our preliminary result indicates significant differences among the time average populations sampled. This finding, tentatively indicate the influence of environmental gradients among the sampled sites. Our observations corroborate previous conclusions arrived in several papers working on the “propagule method”, which seeks to examine the ecology of benthic foraminifera through their mode of dispersal and settlement.
Upper mantle structure beneath Bulgaria obtained by receiver function analysis
Authors: Georgieva Gergana , Vinnik Lev , Oreshin Sergey , Makeyeva Larissa , Dragomirov Dragomir , Buchakchiev Valentin , Dimitrova Liliya
Published: March 2022

Deep structure beneath the central part of the Balkan Peninsula was studied using P and S receiver function technique. Data from seismic stations from the Bulgarian National Seismological Network and several stations from neighbouring countries were used. Depth of Mohorovicic discontinuity has been estimated between 28–30 km in northern and central Bulgaria to 50 km in southwestern of Bulgaria. The 410 km mantle boundary is uplifted by 10 km relative to nominal depth in the area of Rhodopean Massif. In northern Bulgaria, the boundary is lowered by 10 km. Indications of a low-velocity layer are present at a depth exceeding 410 km. The thickness of the asthenosphere is estimated as 50 km and the depth of lithosphere-asthenosphere (LAB) boundary varies between 40 and 60 km.

The results of this study have been published in Vinnik et. al., Izvestiya, Physics of the Solid Earth, 2021, Vol. 57, No. 6, pp. 849–863. This research has been carried out as part of a joint project supported by the National Science Foundation of Bulgaria (grant no. KP-06-RUSIA/27.09.2019) and the Russian Foundation for Basic Research (RFBR, grant no. 19-55-18008 Bolg_a).
Photovoltaic green roofs – On the role of experimental hydrology to feature the acceptance of interdisciplinary and sustainable solutions for both climate change mitigation and adaptation
Authors: Förster Kristian , Westerholt Daniel , Lösken Gilbert
Published: March 2022

While the added value of green roofs for mitigating rainfall extremes in urban drainage systems has been addressed in numerous studies, the microscale spatial redistribution of rainfall by solar panels (photovoltaic modules) mounted on green roofs and its impact on hydrology has hardly been studied so far. However, considering both green roofs and rooftop photovoltaic installations are emerging topics relevant for decision makers, since their combination supports both climate change adaptation (transforming grey to green infrastructure in order to cope with extreme rainfall in urban areas) and climate change mitigation (energy transformation). In the framework of an experimental study, we shed light on the hydrological and hydrodynamic effects of rooftop photovoltaic installations mounted on green roofs and how this contributes to the development of sustainable solutions in an interdisciplinary setting. Since solar panels redirect rainfall to the “green” fraction of the roof not covered by solar panels, the green roof part is in effect subject to higher rainfall and hence intensified surface runoff generation. Promising results were still obtained in a first investigation, where a photovoltaic green roof has been irrigated by a 100 years design storm with 27 mm over 15 minutes: the runoff coefficient (i.e., the percentage of rainfall that becomes runoff) at the end of the rainfall event amounts to only 23%, even though surface runoff occurred after 13 minutes. Based on this first investigation, a systematic measurement campaign has been launched to scrutinize the impact of the microscale spatial rainfall redistribution by solar panels on the runoff coefficient. In this presentation, we show the results of the first investigation along with results achieved in the systematic measurement campaign, which considers different vertical layer structures as well as various flow lengths and slopes of the photovoltaic green roof. In parallel, green roofs without photovoltaic rooftop installations are investigated alongside as a benchmark. In essence, our results suggest to consider both green roofs and photovoltaic rooftop installations to support both climate change mitigation and adaptation, which are important questions that decision makers are simultaneously confronted with. This way, this presentation highlights how experimental hydrology and interdisciplinary collaboration can contribute to address policy-related emerging research. Given that an obligation to install solar panels is expected in numerous countries, this kind of research might endorse new design approaches in future green roof design guidelines relevant for practitioners.

 
Moving the frontier of comparative erosion measurements under different agricultural schemes – Development of a long-term, high-resolution, 4D erosion measurement site of the Bavarian Agricultural Institute in Lower Bavaria (Germany)
Authors: Ebertseder Florian , Mitterer Johannes , Disse Markus
Published: March 2022

Today, erosion is increasing in many intensively used agricultural regions with fertile soils. At the same time, scientists expect that the intensity of heavy precipitation events, their erosivity, drought intensity and persistance will increase significantly through climate change. In combination with more strict regulations to protect the natural environment from nutrients and hazardous substances (such as herbicides and micro-plastics), it is challenging to balance the interests of food (and energy) production and environmental protection.

Therefore, we design and establish a worldwide unique measurement plot at the Bavarian Agricultural Institute (LfL) to assess different combinations of four- and six-year crop rotation schemes and machining methods concerning their long-term soil fertility, stability and resilience against climate change effects and environmental impacts, focusing on compound effects. The plot to measure and compare soil-water retention, nutrient fluxes, surface runoff, and erosion masses has an area of four acres and 14 parallel crop strips. Crop cultivation, experiments and measurements with and without artificial rain will be performed for more than ten years after a three-year set-up phase, will have a 4D (3D spatial plus temporal) high-resolution design and combine established and innovative measurement and management techniques, such as artificial intelligence, neural networks, deep learning, and robotics. Finally, up-to-date process-based hydrological modelling will incorporate the measurement data to increase our process understanding and enable upscaling to catchment scales.

This contribution to EGU 2022 will inform and include the scientific community during the set-up phase about the running and planned activities to build an international scientific network, discuss our approaches, efficiently use the existing scientific knowledge, and initiate future collaborations around the measurement financed by the German federal state of Bavaria.
Layer-specific imaging and monitoring in the Groningen subsurface using seismic interferometry
Authors: Shirmohammadi Faezeh , Draganov Deyan , Ras Paul , Wapenaar Kees
Published: March 2022

Seismic interferometry (SI) is a method that retrieves new seismic traces from the cross-correlation of existing traces, where one of the receivers acts as a virtual seismic source whose response is retrieved at other receivers. When using sources only at the surface, and so-called one-sided illumination of the receivers occurs, not only desired physical reflections are retrieved, but also non-physical (ghost) reflections. These non-physical reflections are caused by internal reflections inside subsurface layers. They are thus particularly interesting to use for monitoring changes in the specific subsurface layer that causes them to appear in the SI result because they could provide valuable information about the physical properties of the subsurface.

We illustrate the potential of SI with active-source data from numerical acoustic modelling using the Groningen subsurface model. This model describes the natural gas field located in the Groningen province in the northeastern part of the Netherlands. The reservoir of the Groningen gas field is located at depths between 2600 m and 3200 m, the total thickness ranges from approximately 100 m to 300 m. The Groningen field is cut by several fault systems, subdividing the field into a large number of fault blocks, and it is a clear example of induced seismicity by gas production.

We investigate the utilization of non-physical reflections retrieved from surface active-source data using SI by cross-correlation and auto-correlation. With multi-offset gathers, besides physical reflections, we retrieve non-physical reflections as well; by muting undesired reflections, we can retrieve better target-related non-physical reflections. To illustrate the potential of the non-physical reflections for monitoring purposes, we apply velocity changes in the Groningen reservoir. With zero-offset gathers, which are retrieved from SI by auto-correlation, we show that in case of velocity changes, the non-physical reflections show a clear change; furthermore, they show a good agreement with the geometry of specific subsurface layers, specifically with the faulted structure. Thus, we can utilize non-physical reflections for imaging and monitoring in the Groningen reservoir.
Improving the ionospheric state estimate during geomagnetic storm time through assimilation of neutral density data
Authors: Fernandez-Gomez Isabel , Kodikara Timothy , Borries Claudia , Forootan Ehsan , Schmidt Michael , Codrescu Mihail
Published: March 2022

During geomagnetic storms, communication and navigation instruments can be dramatically affected by the rapid changes that occur in the upper atmosphere. The assimilation of data in physics-based models such as the Coupled Thermosphere Ionosphere Plasmasphere electrodynamics (CTIPe) model through and ensemble Kalman filter, can improve the representation of the thermosphere-ionosphere (TI) system. Due to the coupled nature of the TI system, the ionosphere is affected by, among others, changes in the neutral atmosphere. In this study, we investigate the capability of the CTIPe model to provide better estimates of the ionosphere by improving its specification of the thermosphere via data assimilation. Here, we assimilate thermospheric mass density (TMD) observations from the Swarm mission normalized to 400 km altitude during the 2015 St. Patrick’s Day storm. The changes that occur in the ionosphere due to assimilation of TMD data are measured by means of the difference between the model results with and without assimilation. To measure the improvement gained with data assimilation, we compare with independent measurements of electron density along the orbit of GRACE (Gravity Recovery and Climate Experiment) satellite, that shows a reduction in the root mean square error (RMSE) by a 22% with respect to the non-assimilation run. The impact on the global scale is measured by comparing the CTIPe model results with the corresponding output of the 3D B-Spline electron density model. The results illustrate that the electron density equatorial region is the most affected region by assimilation of TMD, with an average RMSE reduction of 25% at the assimilation altitude of 400 km.
The end of the atmospheric xenon Archean’s evolution: a study of the Great Oxygenation Event period
Authors: Ardoin Lisa , Broadley Micheal , Almayrac Matthieu , Avice Guillaume , Byrne David , Tarantola Alexandre , Lepland Aivo , Saito Takuya , Komiya Tsuyoshi , Shibuya Takazo , Marty Bernard
Published: March 2022

Several geochemical tracers (S, C, O, Xe) underwent irreversible global changes during the Precambrian, and in particular during the Great Oxygenation Event (GOE), between the Archean and Proterozoïc eons [1]. Xenon is of particular interest as it presents a secular isotopic evolution during the Archean that ceased around the time of the GOE. In this regard Xe is somewhat analogous to mass-independent fractionation sulfur (MIF-S) in that it can be used to categorically identify Archean atmospheric components [2]. Xe isotopes in the modern atmosphere are strongly mass-dependent fractionated (MDF-Xe), with a depletion of the light isotopes relative to the heavy ones. There was a continuous Xe isotope evolution from primitive Xe to modern Xe that ceased between 2.6 and 1.8 Ga [2] and this evolution has been attributed to coupled H+-Xe+ escape to space [3].

The purpose of this project is to document the Xe composition of the paleo-atmosphere trapped in well-dated hydrothermal quartz fluid inclusions with ages covering the Archean-Proterozoic transition to better constraint its link with the GOE.

We have measured an isotopically fractionated Xe composition of 2.0 ± 1.8 ‰ relative to modern atmosphere at 2441 ± 1.6 Ma, in quartz vein from the Seidorechka sedimentary formation (Imandra-Varzuga Greenstone belt, Russia). A slightly younger sample from the Polisarka sedimentary formation (Imandra-Varzuga Greenstone belt, Russia) of 2434 ± 6.6 Ma does not record such fractionation and is indistinguishable from the modern atmospheric composition. A temporal link between the disappearance of the Xe isotopes fractionation and the MIF-S signature at the Archean-Proterozoic transition is clearly established for the Kola Craton. The mass-dependent evolution of Xe isotopes is the witness of a cumulative atmospheric process that may have played an important role in the oxidation of the Earth's surface [3], independently of biogenic O2 production that started long before the permanent rise of O2 in the atmosphere [4].

 

[1] Catling & Zahnle, 2020, Sciences Advances 6, eaax1420. [2] Avice et al., 2018, Geochimica et Cosmochimica Acta 232, 82-100 [3] Zahnle et al., 2019, Geochimica et Cosmochimica Acta 244, 56-85. [4] Lyons et al., 2014, Nature 506, 307-315.