bluuebunny/crossref_metadata_2025 huggingface dataset:
Upstream flow effects revealed in the EastGRIP ice-core using a Monte Carlo inversion of a 2D ice-flow model
Authors: Gerber Tamara Annina , Hvidberg Christine , Grinsted Aslak , Jansen Daniela , Franke Steven , Rasmussen Sune Olander , Sinnl Giulia , Dahl-Jensen Dorthe
Published: March 2021

The North East Greenland ice-stream (NEGIS) is the largest active ice-stream on the Greenland ice-sheet and is a crucial contributor to the ice-sheet mass balance. To investigate the ice-stream dynamics and to gain information about the past climate, a deep ice-core is drilled in the upstream part of the NEGIS, termed the East Greenland ice-core project (EastGRIP). Upstream flow effects introduce non-climatic bias in ice-cores and are particularly strong at EastGRIP due to high ice-flow velocities and the location in an ice-stream on the eastern flank of the Greenland ice-sheet. Understanding and ultimately correcting for such effects requires information on the source area and the local atmospheric conditions at the time of ice deposition. We use a two-dimensional Dansgaard-Johnsen model to simulate ice-flow along three approximated flow-lines between the summit of the ice-sheet and EastGRIP. Model parameters are determined using a Monte Carlo inversion by minimizing the misfit between modeled isochrones and isochrones observed in radio-echo-sounding images. We calculate backward-in-time particle trajectories to determine the source area of ice found in the EastGRIP core today and present estimates of surface elevation and past accumulation-rates at the deposition site. The thinning function and accumulated strain obtained from the modeled velocity field provide useful information on the deformation history in the EastGRIP ice. Our results indicate that increased accumulation in the upstream area is predominantly responsible for the constant annual layer thickness observed in the upper part of the ice column at EastGRIP. Inverted model parameters suggest that the imprint of basal melting and sliding is present in large parts along the flow profiles and that most internal ice deformation happens close to the bedrock. The results of this study can act as a basis for applying upstream corrections to a variety of ice-core measurements, and the model parameters can be useful constraints for more sophisticated modeling approaches in the future. 
Changes in mechanisms and intensity of Western U.S. floods, 1960-2013
Authors: Fayne Jessica , Huang Huilin , Fischella Mike , Liu Yufei , Ban Zhaoxin , Li Dongyue , Cavanaugh Kyle , Lettenmaier Dennis
Published: March 2021

Extreme precipitation, a critical factor in flooding, has selectively increased with warmer temperatures in the Western U.S. Despite this, the streamflow measurements have captured no noticeable increase in large-scale flood frequency or intensity. As flood studies have mostly focused on specific flood events in particular areas, analyses of large-scale floods and their changes have been scarce. For floods during 1960-2013, we identify six flood generating mechanisms (FGMs) that are prominent across the Western U.S., including atmospheric rivers and non-atmospheric rivers, monsoons, convective storms, radiation-driven snowmelt, and rain-on-snow, in order to identify to what extent different types of floods are changing based on the dominant FGM. The inconsistency between extreme precipitation and lack of flood increase suggests that the impact of climate change on flood risk has been modulated by hydro-meteorological and physiographic processes such as sharp increases in temperature that drive increased evapotranspiration and decreased soil moisture. Our results emphasize the importance of FGMs in understanding the complex interactions of flooding and climatic changes and explain the broad spatiotemporal changes that have occurred across the vast Western U.S. for the past 50 years.
Extraction of Nonlinear Dynamics of Heterogeneous Reactions Based on Sparse Modeling
Authors: Ito Masaki , Kuwatani Tatsu , Oyanagi Ryosuke , Omori Toshiaki
Published: March 2021

Heterogeneous reactions are chemical reactions with conjugation of multiple phases, and they have the intrinsic nonlinearity of their dynamics caused by the effect of surface area between different phases. In earth science, it is important to understand heterogeneous reactions in order to figure out the dynamics of rock formation near surface of the earth. We employ sparse modeling algorithm and sequential Monte Carlo algorithm to partial observation problem, in order to simultaneously extract substantial reaction terms and surface models from a number of candidates. Using our proposed method, we show that heterogeneous reactions can be estimated successfully from noisy observable data under conditions that the number of observed variables is less than that of hidden variables.
The Resiliency of High-Altitude Watershed to Dry Condition Under the Changing Climate
Authors: Fatima Eshrat , Rahim Akif , ul Hasson Shabeh , Hassan Mujtaba , Aziz Farhan , Yousaf Muhammad
Published: March 2021

The hydrological cycle is generally known as a recurring result of various forms of water movement and changes in its physical state in nature over a specific area of ​​the earth (river or Lake Basin, a continent, or the whole earth). It is most likely that the increase in global warming will intensively affect the hydrological cycle regionally and globally which will ultimately affect the ecosystem, public health, and municipal water demand. Therefore, the resiliency of watershed to extreme events play a vital role to understand the health of the watershed. This study aims to quantify the resiliency of the Hunza watershed, which lies in the Western Karakoram, to dry conditions under the climate change projections i.e. RCPs 2.6, 4.5, and 8.5. We used a fully distributed hydrological model SPHY to simulate the impact of climate change on future water availability. The SPHY Model was calibration and validation for the time periods (1994-2000) and (2001-2006) respectively. The performance of the model was tested through statistical analysis such as Nash-Sutcliffe efficiency (NSE), coefficient of determination (R2), percentage of bias (PBIAS), and root mean square error (RMSE).To develop future water scenarios, the daily temperature, and precipitation data were obtained from the CORDEX South Asia domain under three Representative Concentration Pathways (RCPs). The empirical quantile mapping method was used for the correction of the daily temperature and precipitation biases under the regional scale. The model was run for near (2007-2036), mid (2037-2066), and far-future (2067-2096) climate projections i.e. RCP2.6, RCP4.5, and RCP8.5. The resilience of watershed defined as the speed of recovery from dry conditions. The monthly Streamflow Drought Index (SDI) was used as an indicator of the dry condition. The resiliency of the watershed determines with the threshold levels of -0.5 and -1.0. The analysis indicates that the resiliency of the watershed has increased from 0.3 to 0.5 in the future under the RCP of 2.6. The value of resilience under the RCP of 4.5 is 0.29, 0.45, and 0.52 for near, mid, and far futures respectively. Under extreme climate conditions RCP 8.5, the watershed resilience is 0.2 in the near future and 0.3 in the mid-future, and 0.6 for the far future. Therefore, it can be concluded that the health of the reservoirs will be very good in the future to stabilize the drought.  
Using Electric Resistivity Tomography and Borehole Logs to Detect Sedimentation Changes in a Gravel-Bed Ephemeral Channel
Authors: Martínez-Segura Marcos A. , Conesa-García Carmelo , Pérez-Cutillas Pedro , Vásconez-Maza Marco D.
Published: March 2021

Differences in deposit geometry and texture with depth along ephemeral gravel-bed streams strongly reflect fluctuations in bedload, which occur due to environmental changes at the basin scale and morphological channel adjustments. In this study, non-destructive methods, 2D and 3D electrical resistivity tomography(ERT), have been combined with datasets from borehole logs to identify, quantify and analyze the internal geometry of cross-sections of the gravel-bed ephemeral channel, known as Azohía Rambla (southeastern Spain). The electrical survey was performed through longitudinal and transverse profiles in two channel reaches, upper and middle stretches. Both profiles utilized 28 stainless steel electrodes reaching 14-30 m in length and an investigation depth of 3-5 m, approximately. Electrical resistivity values were correlated with data obtained from the samples collected from borehole logs (e.g. sediment strength, grain size distribution, compaction, porosity (ϕ), and hydraulic conductivity (k)). To determine ϕ and K granulometric and morphometric variables, such as shape-sphericity indices, particle sorting, effective grain-sizes and void ratios, were used.

The alluvial channel-fills showed the superposition of four layers with uneven thickness and arrangement: 1) a lower sandy-gravel body, scarcely thick, characterized by moderate resistivity (150-500 Ω · m); 2) a thicker intermediate layer, with moderate to high resistivity values (500 to 1600 Ω · m); and 3) an upper set composed of coarse gravel and supported matrix, ranging from 1600 to 3000 Ω · m, and a narrow subsurface layer, the most resistive (> 3000 Ω · m), corresponding to the most recent armored deposits (gravel and pebbles). Consequently, the ERT results coupled with borehole data suggest that since the channel entrenchment in the Miocene marl substrate, different pulses of vertical sedimentary accretion were produced, denoting a general trend to increase in grain-size (coarsening-upwards) and hydraulic conductivity towards the top of the sedimentary sequence. This research was funded by ERDF/Spanish Ministry of Science, Innovation and Universities—State Research Agency/Project CGL2017-84625-C2-1-R; State Program for Research, Development and Innovation Focused on the Challenges of Society.
Final mass balance of Fukushima released radiocaesium in our environment
Authors: Aoyama Michio , Inomata Yayoi , Tsumune Daisuke , Tsubono Takaki
Published: March 2021

One of the greatest results obtained by analyzing seawater samples from the North Pacific Ocean was the estimation of the total amount of 137Cs in the North Pacific to be 15-18 PBq (Aoyama et al., 2016). This estimation has been validated by two methods described by Tsubono et al. (2016) and Inomata et al. (2016). Coastal modeling results gave the amount of 137Cs direct discharge from the FDNPP to coastal waters to be (3.5 ± 0.7) PBq (Tsumune et al., 2012) which was the first and the most accurate result. Since the amount of direct discharge was accurately determined, the amount of 137Cs released into the atmosphere was also properly determined by the mass balance consideration as discussed in Aoyama et al. (2016a). 

For the calculation of the final mass balance, we did not include several results as they did not cover the whole region, or they included the amount of atmospheric fallout as part of the direct discharge. The total amount of radiocesium released to the atmosphere was estimated to be from 8.1 PBq (Yumimoto et al., 2016) to 36 PBq (Stohl et al., 2O12). Based on mass balance consideration we conclude that (15.2-20.4) PBq of the FDNPP-derived 137Cs might be a reasonable value for the total atmospheric release (supported by Aoyama et al., 2016a; Katata et al., 2015; Mathieu et al., 2012; Saunier et al., 2013; Winiarek et al., 2014). The estimated land deposition is (3.4–6.2) PBq (Aoyama et al., 2016). The estimated 137Cs inventories in the North Pacific are in the range (15.2–18.3) PBq, as obtained by Tsubono et al. (2016) and  Inomata et al. (2016), while only (3–6) PBq was the contribution from the direct discharge (consensus value, Aoyama et al., 2016), although our previous estimate was more precise, (3.5 ± 0.7) PBq. For atmospheric deposition to the North Pacific, the estimated values are in the range (11.7–14.8) PBq (Aoyama et al., 2016; Inomata et al., 2016; Tsubono et al., 2016).

The radiocesium inventories in the interior domains of the North Pacific Ocean have been estimated. The radiocesium inventory in the STMW (Subtropical Mode Water) is (4.2 ± 1.1) PBq (Kaeriyama et al., 2016), and (7.9 ± 1.4) PBq in the surface layer (Inomata et al., 2018b). In the CMW (Central Mode Water), the radiocesium inventory is (2.5 ± 0.9) PBq (Inomata et al., 2018b). The radiocesium sediment inventory is (0.20 ± 0.06) PBq (Otosaka, 2017). The inventory in marine biota might be less than 200 GBq (Aoyama et al., 2019).
Robustness of modelling the forced change of the ENSO-Indian monsoon teleconnection
Authors: Bodai Tamas , Lee June-Yi
Published: March 2021

Beside means, the forced response of the internal variability of the climate system is also of considerable practical interest. Teleconnections are one aspect of internal variability, and they derive their importance partly from their role in seasonal predictability. We compare the forced response of the ENSO-Indian monsoon teleconnection — as a first step of investigating the robustness of its modelling — in two Earth System Models, making use of the Large Ensemble data sets of the MPI-GE and CESM1-LE. We find considerable similarities of climatologies and the forced responses with respect to spatial patterns, in terms of e.g. MCA (Maximum Covariance Analaysis) modes. However, because of the mismatch of these patterns, both in terms of their weight and shape, the teleconnection associated with restricted areas, such as the domain of the so-called All-India Summer Monsoon Rainfall (AISMR) differ very considerably in the two models. While most representations of the teleconnection involving the principal modes of variability show a strengthening in the MPI-GE, not much change is detectable in the CEMS1-LE. In fact, the second modes, EOF2 or MCA2, are associated with much more change in the CESM1.
ALOS-2/PALSAR-2 dual-polarized L-band data for sea ice parameter estimation and sea ice classification 
Authors: Karvonen Juha
Published: March 2021

This research is related to the JAXA 6th Research Announcement for the Advanced Land
Observing Satellite-2 (ALOS-2) project "Improved Sea Ice Parameter Estimation with L-Band SAR (ISIPELS)".
In the study ALOS-2/PALSAR-2 dual-polarized Horizontal-transmit-Horizontal-receive/
Horizontal-transmit-Vertical-receive (HH/HV) ScanSAR mode L-band  Synthetic Aperture Radar (SAR) imagery
over an Arctic study area were evaluated for their suitability for operational sea ice monitoring.
The SAR data consisting of about 140 HH/HV ScanSAR ALOS-2/PALSAR-2 images were acquired during the winter 2017.
These L-band SAR data were studied for estimation of different sea ice parameters:
sea ice concentration, sea ice thickness, sea ice type, sea ice drift. Also some comparisons with nearly
coincident C-band data over the same study area have been made. The results indicate that L-band
SAR data from ALOS-2/PALSAR-2 are very useful for estimating the studied sea ice parameters and equally good
or better than using the conventional operational dual-polarized C-band SAR satellite data.

 
Observations of nonlinear internal waves of tidal origin in the northeastern East China Sea
Authors: Lee Seung-Woo , Nam SungHyun
Published: March 2021

Oceanic nonlinear internal waves (NLIWs) play an important role in regional circulation, biogeochemistry, energetics, vertical mixing, underwater acoustics, marine engineering, and submarine navigation, most commonly generated by the interaction between barotropic tides and bathymetry. Here, we present characteristics of first mode NLIWs observed using high-resolution in-situ data collected using moored and underway temperature sensors in a relatively flat bottom in the northeastern East China Sea during May 15-28, 2015. During the experiment, totally 34 events of first mode NLIWs were identified and characterized with amplitude of 4–16 m, characteristic width of 310–610 m, propagation speed of 0.53–0.56 m s-1, and propagation direction (mainly southwestward propagation), respectively. Most NLIWs were observed during period of spring tide with phases locked to semidiurnal barotropic tides. Generation and propagation of the first mode NLIWs observed in the region are discussed in relation to satellite images and historical hydrographic data collected in the region. Our results support significance of first mode NLIWs and their interactions on turbulent mixing and regional circulation particularly in a broad and shallow continental shelves where the NLIWs generated from multiple sources propagate into multi-directions experiencing wave-wave interactions.
The Global Geodetic Observing System (GGOS) – infrastructure underpinning Earth science
Authors: Miyahara Basara , Sánchez Laura , Sehnal Martin
Published: March 2021

The Global Geodetic Observing System (GGOS) is the contribution of Geodesy to the observation and monitoring of the Earth System. Geodesy is the science of determining and representing the shape of the Earth, its gravity field and its rotation as a function of time. A core element to reach this goal are stable and consistent geodetic reference frames, which provide the fundamental layer for the determination of time-dependent coordinates of points or objects, and for describing the motion of the Earth in space. Traditionally, geodetic reference frames have been used for surveying, mapping, and space-based positioning and navigation. With modern instrumentation and analytical techniques, Geodesy is now capable of detecting time variations ranging from large and secular scales to very small and transient deformations with increasing spatial and temporal resolution, high accuracy, and decreasing latency. GGOS has been working closely with components of International Association of Geodesy (IAG) to provide consistent and openly available observations of the spatial and temporal changes of the shape and gravity field of the Earth, as well as the temporal variations of the Earth’s rotation. These efforts make available a global picture of the surface kinematics of our planet, including the ocean, ice cover, continental water, and land surfaces, as well as estimates of mass anomalies, mass transport, and mass exchange in the System Earth. Surface kinematics and mass transport together are the key to global mass balance determination, and are an important contribution to understanding the energy budget of our planet. In order to play its vital role, GGOS has following missions; a) to provide the observations needed to monitor, map, and understand changes in the Earth’s shape, rotation, and mass distribution, b) to provide the global geodetic frame of reference that is the fundamental backbone for measuring and consistently interpreting key global change processes and for many other scientific and societal applications, c) to benefit science and society by providing the foundation upon which advances in Earth and planetary system science and applications are built. For the mission, GGOS works tighter with components of the IAG, more specifically, IAG Services, IAG Commissions and IAG Inter-Commission Committees. The IAG Services provide the infrastructure and products on which all contributions of GGOS are based, and the IAG Commissions and IAG Inter-Commission Committees provide expertise and support to address key scientific issues within GGOS. Together with the IAG components, GGOS provides the fundamental infrastructure underpinning Earth sciences and their applications.
The evolution and non-fickian flow of local stagnant zones in hierarchically nested groundwater flow system under different rainfall infiltration intensity
Authors: Sun Ronglin , Jiang Liqun , Liang Xing , Jin Menggui
Published: March 2021

Groundwater plays an active role in certain geologic processes that has been recognized in numerous subdisciplines for a long time. According to Toth (1963, 2009), gravity-driven regional groundwater flow is induced by elevation differences in the water table and its pattern is self-organized into hierarchical sets of local, intermediate and regional flow systems.  Convergence of two flow systems results in a stagnant zone called hydraulic trap which is under the discharge area, and diverge of two flow systems results in a stagnant zone called quasi-stagnant zone which is under the water divide. These stagnant zones have been found to be critical to accumulation of transported mineral matter. Based on analytical and numerical solutions, some researchers reported that the local stagnant point or zone that are located under the local counter directional flow system. There is a question that whether hydraulic trap and quasi-stagnant zone is separate or integrate, and whether they are located under the discharge area or water divide or counter directional flow systems.

In this study, two-dimensional numerical cross-sectional model is used to investigate the effect of climate change on local stagnant zones and whether the hydraulic trap and quasi-stagnant zone is separate or integrate. Considering the climate change of basin and the change of rainfall infiltration intensity, a flux upper boundary is used to simulate the rainfall recharge. Then a synthetic homogeneous sandbox with three potential sinks is used to validate the evolution of the hierarchical nested groundwater flow systems considering different rainfall infiltration intensity. Salt tracer test is used to investigate the effect of stagnant zones on solute transport.

According to numerical results, we concluded that the hydraulic traps and quasi-stagnant are possible to be separate only for simple local systems and the two local stagnant zones are located on two sides of the counter directional flow system. When nested flow systems occur, such as local-intermediate, local-intermediate-local, local-regional, the local hydraulic traps and quasi-stagnant zones are always integrated under the local counter directional flow systems. Laboratory results show that when the rainfall infiltration intensity reduce, the groundwater flow pattern will change and the penetration depth and scope of counter directional local flow system will decrease. The corresponding local stagnant zone will slowly be closing to the discharge area of that counter directional local flow system. Salt tracer tests show that there are obvious non-fickian phenomenon in the local stagnant zones in hierarchically nested flow systems even in the homogeneous aquifer.
Spatial Contribution to Flood Risk Analysis (COSPARIN)
Authors: Guillaume Lahache , Alix Roumagnac , Sylvain Chave
Published: March 2021

After having developed an operational flood risk management service in France for more than 15 years, PREDICT Services was asked to deploy this service internationally.

PREDICT Services has started the transfer of the methods internationally and particularly in Morocco. The first feedbacks of experiences show that spatial data take an essential part in it but that today the quality of these products needs to be improved and that the durability of the access to the data must be secured.

PREDICT Services has partnered with Météo-France and CEREMA to carry out this project.

We have developed with Météo-France a global precipitation estimation data thanks to an artificial intelligence algorithm specific to rainfall estimation computation which considers the discrimination of stratiform and convective clouds, their precipitation estimates, the evaporation correction of precipitation, seasonality, latitude.... These data are also processed in a training file to calibrate the data according to several parameters and in particular existing radar data.

This data is available every 30 minutes at a resolution of 5km around the world.

In addition, with CEREMA, we can generate flood zones thanks to its Exzeco model, applied on the new Airbus digital terrain models (WorldDEM) based on satellite data, thus improving the overall accuracy.

A pilot project has started and will last 2 years to validate the methods and data developed during the project in the Indian Ocean area (Reunion - Mauritius - Mayotte - Madagascar) so that they can be deployed worldwide. Global rainfall estimation as well as the estimation of floodable areas elaborated thanks to satellite data.

These data will be shared via a web platform which will allow users (insurers, meteorological direction, States) to take control of these tools. A real time assistance service 24/24, 365/365, already set up by PREDICT Services for more than 15 years, will support them in the management of risk events.

This data, essential for crisis management and anticipation of natural risks, will allow the different actors to better anticipate and be better prepared during risk events.
Clustering of Fast Coronal Mass Ejections during Solar Cycles 23 and 24 and Implications for CME–CME Interactions
Authors: Rodriguez Gomez Jenny Marcela , Podlachikova Tatiana , Veronig Astrid , Ruzmaikin Alexander , Feynman Joan , Petrukovich Anatoly
Published: March 2021

Coronal Mass Ejections (CMEs) and their interplanetary counterparts (ICMEs) are the major sources for strong space weather disturbances. We present a study of statistical properties of fast CMEs (v≥1000 km/s) that occurred during solar cycles 23 and 24. We apply the Max Spectrum and the declustering threshold time methods. The Max Spectrum can detect the predominant clusters, and the declustering threshold time method provides details on the typical clustering properties and timescales. Our analysis shows that during the different phases of solar cycles 23 and 24, fast CMEs preferentially occur as isolated events and in clusters with, on average, two members. However, clusters with more members appear, particularly during the maximum phases of the solar cycles. During different solar cycle phases, the typical declustering timescales of fast CMEs are τc =28-32 hrs, irrespective of the very different occurrence frequencies of CMEs during a solar minimum and maximum. These findings suggest that  τc   for extreme events may reflect the characteristic energy build-up time for large flare and CME-prolific active regions. Statistically associating the clustering properties of fast CMEs with the disturbance storm time index at Earth suggests that fast CMEs occurring in clusters tend to produce larger geomagnetic storms than isolated fast CMEs. Our results highlight the importance of CME-CME interaction and their impact on Space Weather.
Proposal of a typology of karst systems functioning based on relevant indicators of karst springs hydrodynamics
Authors: Cinkus Guillaume , Mazzilli Naomi , Jourde Hervé
Published: March 2021

10% of the world’s population is dependent on karst water resources for drinking water. Understanding the functioning of these complex and heterogeneous systems is therefore a major challenge for long term water resource management. Over the past century, different methods have been developed to analyse hydrological series, and subsequently characterize the functioning of karst systems. These methods can be considered as a preliminary step in the development and design of hydrological models of karst functioning for sustainable water resource management. Recent progress in analytical tools, as well as the emergence of data bases of discharge time series (e.g. the French SNO KARST database and the WoKaS database at global scale) allow reconsidering former typology of karst system hydrodynamic responses. Ten karst systems and associated spring discharge time series were considered for developing the typology. The systems are well-known with a high-quality monitoring and they cover a wide range of hydrological functioning, which ensure the relevance of the analyses. The methodology for the assessment and the development of the typology consisted in (i) the analysis of springs discharge time series according to four different methods, (ii) the selection or proposal of the most relevant indicators of karst systems hydrodynamics, and (iii) the interpretation of the information from these indicators based on principal component analysis and clustering techniques. A typology of karst systems accounting for 6 different classes is finally proposed, based on 3 aspects of functioning: the capacity of dynamic storage, the draining dynamic of the capacitive function and the variability of the hydrological functioning. The typology was applied to a wider dataset composed of spring discharge of 78 karst systems. The results show a relevant distribution of the systems among the different classes.
Gender equality officers: which activities can we do to improve gender equality in STEM? Examples from MARUM women’s representatives
Authors: Lefebvre Alice , Bender Vera B. , Schnieders Luzie
Published: March 2021

Many institutes have equal opportunity or gender equality officers. They are usually responsible to ensure that equal opportunity and gender equality laws are applied at their institute but also offer local support. The actions from these officers might greatly help to improve equal opportunities and gender equality.

At MARUM – Center for Marine Environmental Sciences, University of Bremen, Germany, a collective of three women was elected in January 2019 as decentralised women’s representatives. Our overarching goal is to advice and support all scientists and students at MARUM, as well as the director and committees, in the implementation of the legally-fixed gender equality duty (Bremisches Hochschulgesetz / Higher Education Act of the State of Bremen). As such, we have implemented several actions to promote gender equality at MARUM.

With the present contribution, we would like to present the activities with which we have been engaged and discuss how successful they were, in order to help other gender equality officers in their role. We also hope to hear about other successful actions that have been implemented in order to broaden our actions. Generally, we would like to discuss ideas of useful future actions and exchange with colleagues in this field. A long-term goal is to create a repository of actions which can be taken by equal opportunity and gender equality officers.

Our actions were implemented at a range of levels: directly with the women from MARUM (e.g. network meetings, support in case of conflict, pregnancy checklist), sensibilisation (e.g. invited talk on gendered wording in job advertisement, workshop on writing letters of recommendation, screening of “Picture a Scientist”), institutional (e.g. bi-annual meeting with director, meetings with the other gender equality actors at the university), monitoring (e.g. analysis of the gender of job applicants and selected candidates).

Most actions are very beneficial and well received. We feel it is profitable to act at these different levels, to provide support directly to the women, but also to inform a wide range of actors on gender inequalities. The resources we have at MARUM allows a funding of some activities, which is particularly useful. Because we are scientists ourselves, we have a good and productive exchange with the other women on a peer level. We are greatly encouraged and supported by the fact that people in leadership positions take us seriously and carefully listen to our opinion and feedback. A difficulty which we encounter is that, although the position of women’s representative is officially recognised by the law, we are not given specific time for it. Therefore, the work that we do as gender equality officer is done in addition to our scientific work.
Stable and accurate a posteriori LES of 2D turbulence with convolutional neural networks: Backscatter analysis and generalization via transfer learning
Authors: Guan Yifei , Chattopadhyay Ashesh , Subel Adam , Hassanzadeh Pedram
Published: March 2021

In large eddy simulations (LES), the subgrid-scale effects are modeled by physics-based or data-driven methods. This work develops a convolutional neural network (CNN) to model the subgrid-scale effects of a two-dimensional turbulent flow. The model is able to capture both the inter-scale forward energy transfer and backscatter in both a priori and a posteriori analyses. The LES-CNN model outperforms the physics-based eddy-viscosity models and the previous proposed local artificial neural network (ANN) models in both short-term prediction and long-term statistics. Transfer learning is implemented to generalize the method for turbulence modeling at higher Reynolds numbers. Encoder-decoder network architecture is proposed to generalize the model to a higher computational grid resolution.
Legacy deposits: can a small-scale mining paradigm contribute to the re-processing mining wastes to supply critical raw materials?
Authors: Bodin Jérôme , Bertrand Guillaume , D'Hugues Patrick
Published: March 2021

In line with the perspective of the Raw Material Initiative launched in 2008 by the European Commission to ensure access to and supply of critical raw materials in Europe, the H2020-funded IMPaCT project (Grant no. 730411) aims to develop a Switch-On Switch-Off (SO-SO) concept as an emergence of a new modern small-scale mining paradigm. Its ultimate goal is to increase the viability of many critical metals hosted in small primary deposits, particularly in Europe, by developing a modularized mobile plant (MMP) concept that can economically operate different type of ores in different types of geological and geographical contexts.

In addition, the project addresses the prospect of applying the SO-SO concept and the small-scale mining paradigm with regard to the reprocessing of mineral wastes in Europe. A dataset of legacy deposits of interest for the SO-SO concept was drawn from the ProMine Anthropogenic Concentration (AC) database (built during the European FP7 ProMine project) used as the data source and by applying a sequential-rating as a methodology to rank records and to highlight potential targets.

Apart from national mining wastes registries, the ProMine AC database remains so far the most exhaustive and reliable attempt at a consolidated pan-European database regarding mining wastes. Despite data shortcoming in the ProMine AC database, this study proposes potential targets of mineral wastes for the SO-SO concept in Europe and provides with preliminary information on location, type of waste, commodities content, tonnage and their potential.

To put into perspective the application of the SO-SO concept and the small-scale mining paradigm in regards with mineral wastes reprocessing, this study also proposes generic flowsheets to address specific potential targets identified among the records from the ProMine AC database and based on the preliminary information available. However, the relevancy and completeness of these information still require a case-by-case assessment. As a result, this methodology falls into a scoping approach that could be applied ahead of (pre)feasibility studies.

Combining the re-exploitation of a primary ore deposit along with the reprocessing of its wastes inherited from previous mining and ore processing activities is of great interest in seeking social acceptance. Eventually, in such perspective, a cross survey of the potential of both primary deposits, using the ProMine Mineral Deposits (MD) database, and secondary deposits, using the ProMine AC database, therefore appears as a relevant scoping strategy ahead of implementing small-scale mining.
Comparison of climatic indices with landslide occurrences in Calabria (Southern Italy)
Authors: Petrucci Olga , Aguilar Enric , Pasqua Angela A. , Vicente-Serrano Sergio , Zimbo Fabio , Coscarelli Roberto
Published: March 2021

The most frequent and widespread landslides all over the world are induced by prolonged or heavy rainfall events. These phenomena often cause casualties and damages. Recent research on climate change has evidencing the link between the rainfall tendencies and the increase of damaging geohydrological events. This study has been carried out in the ambit of the EC Project INDECIS, whose aim is to develop an integrated approach to produce a series of climate indicators aimed at the high priority sectors of the Global Framework for Climate Services of the World Meteorological Organization (agriculture, risk reduction, energy, health, water), with the addition of tourism. The study area is Calabria, a region of Southern Italy frequently affected by mass movements and characterized by a highly variable climate. In this study, landslide occurrences in the period 1990-2018 have been collected for the whole territory of Calabria, and clustered according to the five provinces of the region. Moreover, 13 rainfall-based climatic indexes, among those proposed in the INDECIS project, have been calculated for each of the 79 rain gauges presenting complete and homogeneous databases. For each province and for the whole Calabria, the average and the maximum values of the climatic indices have been compared with the landslide occurrences in each year. The comparisons showed the best agreements with the following climatic indices: a) the total annual precipitation (RTA), the annual count of days when daily precipitation amount ≥ 10mm (R10mm), the annual count of days when daily precipitation amount ≥ 20mm (R20mm), the annual total precipitation when daily rainfall is greater than 95th-percentile (R95TOT) and, secondarily, the annual count of days with daily rainfall >= 50 mm (D50mm). For the best matches, the curves interpolating the two databases have been also drawn. The obtained results can be useful to predict the impacts that tendencies of rainfall indices patterns can have on slope stabilities of the territory.

Acknowledgments:

The Project INDECIS is part of ERA4CS, an ERA-NET initiated by JPI Climate, and funded by FORMAS (SE), DLR (DE), BMWFW (AT), IFD (DK), MINECO (ES), ANR (FR) with co-funding by the European Union (Grant 690462)
Controlling metalimnetic bloom of Planktothrix rubescens by a novel water withdrawal strategy: a modelling study
Authors: Mi Chenxi , Frassl Marieke , Hamilton David , Shatwell Tom , Kong Xiangzhen , Boehrer Bertram , Li Yiping , Rinke Karsten
Published: March 2021

Aggregations of cyanobacteria in lakes and reservoirs are commonly associated with surface blooms, but may also occur in the metalimnion as subsurface or deep chlorophyll maxima. Metalimnetic cyanobacteria blooms are of great concern when potentially toxic species, such as Planktothrix rubescens (P. rubescens), are involved. Apparently, metalimnetic blooms of P. rubescens have increased in frequency and severity in recent years so there is a strong need to establish the external factors controlling its growth. We hypothesized that P. rubescens blooms in reservoirs can be managed by modifying the water withdrawal strategy and altering the light climate experienced by the algae. We tested our hypothesis in Rappbode Reservoir by establishing a series of withdrawal and light scenarios based on a calibrated water quality model (CE-QUAL-W2). Our scenarios demonstrated that metalimnetic water withdrawal reduced P. rubescens biomass in the reservoir. According to the simulation results we defined an optimal withdrawal volume to control P. rubescens blooms in the reservoir as approximately 10 million m3 during its blooming period. The numerical results also indicated that P. rubescens growth can be most effectively suppressed if the metalimnetic withdrawal is applied in the early stage of its rapid growth (i.e. before the occurrence of blooms). Additionally, the results showed that P. rubescens biomass gradually decreased with increasing light extinction and nearly disappeared when the extinction coefficient exceeded 0.55 m-1.  Our results indicated that close linkages among in situ measurements, model simulations, empirical growth rate and flushing rate calculations could inform management strategies to minimise the harmful impacts of P. rubescens in water supplies. Such a strategy could be used in reservoir operational strategies as an adaptation way to offset the rise in P. rubescens populations that has been linked to climate change.
Assessing pyro-convective uplift and chemical processing of Biomass Burning plumes in the ECMWF IFS
Authors: Williams Jason , Huijnen Vincent , Bouarar Idir , Belamari Sophie , Remy Samuel , Flemming Johannes
Published: March 2021

CO is an abundant tropospheric pollutant that originates from numerous emission sources. Large CO fluxes are emitted during intense Biomass Burning (BB) events over relatively short periods of a few days, which combined with the tropospheric lifetime of a month, act as a marker for air-masses influenced by burning events. Once lifted out the boundary layer, air masses influenced by BB undergo chemical processing which can be assessed by subsequent changes in tropospheric ozone. Increases in ozone and aerosol in the Free Troposphere influence photolysis at lower levels impact surface air-quality. Therefore, capturing this feedback is a necessary step towards determining tropospheric lifetimes of greenhouse gases and pollutants, which affects the fraction of transport out of the burning regions.

Here we present results from the Integrated Forecasting System (IFS) of ECMWF, which is the core of the Copernicus Atmosphere Monitoring Service (CAMS). We perform simulations with three independent chemistry modules (modified CB05, MOZART, MOCAGE), including variable photolysis schemes and variable approaches for coupling tropospheric aerosol. We choose the simulation year of 2019 corresponding with the FIREXAQ measurement campaign which occurred over California. We subsequently assess the ability of IFS in terms of (i) the representation of the transport of air masses effected by large BB emissions, (ii) the ability towards capturing chemical processing which occurs in such plumes and (iii) using large discrepancies in the simulated tropospheric profiles to imply deficiencies in BB emission estimates.

 
Deep structure of the Atlantic margins and neighboring oceanic crust from wide-angle seismic data and plate kinematic reconstructions.
Authors: Klingelhoefer Frauke , Biari Youssef , Franke Dieter , Funck Thomas , Loncke Lies , Sibuet Jean-Claude , Basile Christophe , Austin James , Rigoti Caesar , Sahabi Mohamed , Benabdellouahed Massinissa , Roest Walter
Published: March 2021

In order to study opening mechanisms and their variation in the Atlantic ocean basins, we compiled existing wide-angle and deep seismic data along conjugate margins and performed plate tectonic reconstructions of the original opening geometries to define conjugate margin pairs. A total of 23 published wide-angle seismic profiles from the different margins of the Atlantic basin were digitized, and reconstructions at break-up and during early stages of opening were performed. Main objectives were to understand how magma-rich and magma-poor margins develop and to define more precisely the role of geologic inheritance (i.e., preexisting structures) in the break-up phase. At magma-poor margins, a phase of tectonic opening without accretion of a typical oceanic crust often follows initial rupture, leading to exhumation of serpentinized upper mantle material. Along volcanic margins the first oceanic crust can be overthickened, and both over- and underlain by volcanic products. The first proto-oceanic crust is often accreted at slow to very slow rates, and is thus of varied thickness, mantle content and volcanic overprint. Accretion of oceanic crust at slow to very slow spreading rates can also be highly asymmetric, so the proto oceanic crust at each side of conjugate margin pairs can differ. Another major aim of this study was to understand the mechanisms of formation and origins of transform marginal plateaus. These are bathymetric highs located at the border of two ocean basins of different ages and are mostly characterized by one or several volcanic phase during their formation. They often form conjugate pairs along a transform margin as it evolves and might have been the last land bridges during breakup, thereby influencing mammal migration and proto-oceanic currents in very young basins. At these plateaus, volcanic eruptions can lead to deposits of (at least in part subaerial) lava flows several km thick, better known by their geophysical signature as seaward dipping reflectors. Continental crust, if present, is heavily modified by volcanic intrusions. These marginal plateaus might form when rifting stops at barriers introduced by the transform margin, leading to the accumulation of heat in the mantle and increased volcanism directly before or after the cessation of rifting.
Global modelling of plastic beaching indicates coastlines and coastal waters as significant plastic reservoirs
Authors: Onink Victor , Jongedijk Cleo , Hoffman Matthew , van Sebille Erik , Laufkötter Charlotte
Published: March 2021

The distribution of plastic in the ocean is poorly constrained, with the mass of floating plastic at the ocean surface being orders of magnitude smaller than estimated plastic inputs. Coastlines likely contain significant amounts of plastic, but inconsistent methodologies between beached plastic observations prevent determining the mass and distribution of globally beached plastic. We present Lagrangian model sensitivity experiments to estimate the beached fraction of marine plastic and to investigate the global distribution of beached plastic on coastlines.

We perform simulations where particles, representing masses of floating plastic, are inserted at the ocean coasts. The particles are then advected by surface currents (HYCOM/NCODA global reanalysis and surface Stokes drift from the WaveWatch III global reanalysis) for 5 years. Beaching is parametrized stochastically using exponentional probability. Here, we test the sensitivity to e-folding time scales between 1 and 100 days, applied when plastic is within the coastal zone, within 10km of the nearest coastline. Resuspension of beached plastic is parameterised exponentially with an e-folding timescale between 69 and 273 days. No other loss processes are implemented.

Between 39-95% of floating plastic mass is beached after 5 years, with the beached fraction depending on the ratio between the beaching and resuspension timescales. In all simulations, at least 77% of floating plastic mass is found either beached or within the coastal zone, indicating coastal regions are a significant reservoir of mismanaged terrestrial plastic. However, plastic entering the ocean from islands or near energetic boundary currents is more likely to reach the open ocean. The distribution of beached plastic is closely related to the input distribution, with the highest concentrations found in Southeast Asia and the Mediterranean.

Our results highlight coastlines and coastal waters as important reservoirs of marine plastic debris and indicate a need for greater understanding of plastic transport near and at the coastlines. Furthermore, improved representation of plastic beaching can help study marine plastic fragmentation, as mechanical stress during the transitions between coastlines and coastal waters and the increased UV exposure of beached plastic likely contribute to the fragmentation.
An inclination-only fold test
Authors: Ma Yiming , Yang Tianshui , Wang Huapei , Hu Shaochen , Wang Mengqing , Zou Di
Published: March 2021

The fold test is inevitably used to determine whether a remanence is acquired prefold. The remanence declinations recorded in rocks may be affected by local rotation. Thus, it is difficult to restore the structure correction’s original orientation, leading to a possible incorrect conclusion of the fold test. However, the tilt correction of inclination is immune to the influence of local rotations. Therefore, we propose a more straightforward fold test based on the inclination-only mean. Examples are given to verify the validity of the inclination-only fold test, which can be applied to data affected by a possible local rotation. The inclination-only fold test should be used to determine the contribution of inclinations. The combined use of the 3-D and inclination-only fold tests is required to evaluate paleomagnetic results from the orogen or sampling sections with unrecognizable plunging folds or near the faults.