bluuebunny/crossref_metadata_2025 huggingface dataset:
The highest altitude paleoecological record of early pastoralism in Africa
Authors: Gil-Romera Graciela , Bittner Lucas , Grady David A. , Epp Laura S. , Ossendorf Götz , Fekadu Mekbib , Zech MIchael , Opgenoorth Lars , Miehe Georg , Lamb Henry F.
Published: March 2021

The advent of pastoralism in Eastern Africa is one of the most significant cultural transformations in the continent’s history. Traditionally, herding origins and its spreading routes have been studied in the lowlands and described as a complex and lengthy process that began before 4 ka BP and lasted until 1.3 ka BP. This cultural transition has long been argued to have been a process involving both environmental change and population movements. Given the current patchy archaeological data, most studies studies conclude that no single factor can be identified as a driver of the onset of herding in Eastern Africa, but almost all evidence is from lowland areas. The higher elevations of the Eastern African mountains are sensitive to climate and environmental change, so may be ideal for testing hypotheses of human-environmental relationships. However, the history of pastoralism in the African highlands, especially its connection with regional herding migrations and Holocene climate change, has thus far been poorly explored with few available records.

 In this contribution, we provide evidence of early pastoral activities at high altitude in the Bale Mountains of southwest Ethiopia. We present a 4000-year multiproxy palaeoecological lacustrine sequence from Garba Guracha, a cirque lake at 3950 m asl, combining palaeoclimatic and palaeoenvironmental proxies. Our record indicates the distinctive presence of faecal fungal spores (Sporormiella, Cercospora, Podospora) and the expansion of pollen and sedaDNA from ruderal plants as early as 3.5 ka. To our knowledge, this is the highest altitude record of early animal husbandry traces on the continent. Coeval with the expansion of pastoralism indicators in Garba Guracha, we find important changes in the lake’s diatom community, as well as climate fluctuations reconstructed from biomarkers; these may be critical for understanding human occupation at high altitudes. However, archaeological studies conducted in the Garba Guracha basin have proved unfruitful in finding permanent settlements of herders, suggesting hypotheses of seasonal resource use.

 We discuss different scenarios of pastoral expansion on the Eastern African highlands under changing local climates, as well as the general context of pastoralist migration across Eastern Africa.
Variable response of North Atlantic deep-sea benthic ecosystems to industrial-era climate change
Authors: O'Brien Charlotte , Spooner Peter , Thornalley David , Wharton Jack , Papachristopoulou Eirini , Pallottino Francesco , Radionovskaya Svetlana , Dutton Nicolas , Li Tianying , Garratt Rebecca , Oppo Delia
Published: March 2021

Traditionally, deep-sea ecosystems have been considered to be insulated from the effects of modern climate change. Yet, with the recognition of the importance of food supply from the surface ocean and deep-sea currents to sustaining these systems, the potential for rapid response of benthic systems to climate change is gaining increasing attention. North Atlantic benthic responses to past climate change have been well-documented using marine sediment cores on glacial-interglacial timescales, and ocean sediments have also begun to reveal that planktic species assemblages are already being influenced by global warming. However, very few ecological time-series exist for the deep ocean covering the Holocene-through-industrial era. Here, we use benthic and planktic foraminifera found in Northeast Atlantic (EN539-MC16-A/B and RAPID-17-5P), Northwest Atlantic (KNR158-4-10MC and KNR158-4-9GGC) and Labrador Sea (RAPID-35-25B and RAPID-35-14P) sediments to show that, in locations beneath areas of major North Atlantic surface water change, benthic ecosystems have also changed significantly over the industrial era relative to the Holocene. We find that the response of the benthos is dependent on changes in the surface ocean near to the study sites. Our work highlights the spatial heterogeneity of these benthic ecosystem changes and therefore the need for local-regional scale modelling and observations to better understand responses to deep-sea circulation changes and modern surface climate change. 
Global biosphere primary productivity over the last 800,000 years reconstructed from the triple-isotope composition of dioxygen trapped in polar ice cores
Authors: Yang Ji-Woong , Landais Amaëlle , Brandon Margaux , Blunier Thomas , Prié Frédéric , Duchamp-Alphonse Stéphanie , Extier Thomas , Bouttes Nathaëlle
Published: March 2021

The primary production, or oxygenic photosynthesis of the global biosphere, is one of the main source and sink of atmospheric oxygen (O2) and carbon dioxide (CO2), respectively. There has been a growing number of evidence that global gross primary productivity (GPP) varies in response to climate change. It is therefore important to understand the climate- and/or environment controls of the global biosphere primary productivity for better predicting the future evolution of biosphere carbon uptake. The triple-isotope composition of O2 (Δ17O of O2) trapped in polar ice cores allows us to trace the past changes of global biosphere primary productivity as far back as 800,000 years before present (800 ka). Previously available Δ17O of O2 records over the last ca. 450 ka show relatively low and high global biosphere productivity over the last five glacial and interglacial intervals respectively, with a unique pattern over Termination V (TV) - Marine Isotopic Stage (MIS) 11, as biosphere productivity at the end of TV is ~ 20 % higher than the four younger ones (Blunier et al., 2012; Brandon et al., 2020). However, questions remain on (1) whether the concomitant changes of global biosphere productivity and CO2 were the pervasive feature of glacial periods over the last 800 ka, and (2) whether the global biosphere productivity during the “lukewarm” interglacials before the Mid-Brunhes Event (MBE) were lower than those after the MBE.
Here, we present an extended composite record of Δ17O of O2 covering the last 800 ka, based on new Δ17O of O2 results from the EPICA Dome C and reconstruct the evolution of global biosphere productivity over that time interval using the independent box models of Landais et al. (2007) and Blunier et al. (2012). We find that the glacial productivity minima occurred nearly synchronously with the glacial CO2 minima at mid-glacial stage; interestingly millennia before the sea level reaches their minima. Following the mid-glacial minima, we also show slight productivity increases at the full-glacial stages, before deglacial productivity rises. Comparison of reconstructed interglacial productivity demonstrates a slightly higher productivity over the post-MBE (MISs 1, 5, 7, 9, and 11) than pre-MBE ones (MISs 13, 15, 17, and 19). However, the mean difference between post- and pre-MBE interglacials largely depends on the box model used for productivity reconstruction.
Fungi play a key role in the restoration of species-rich grasslands: trace-labelling carbon through the food chain
Authors: Morriën Elly , Quist Casper , Cuk Sena , Koppen Jules , Varkevisser Eva , Hannula Emilia
Published: March 2021

Restoring natural plant communities on abandoned agricultural fields can be challenging due to a degraded soil community and a fertilizer legacy. We discovered that fungi are the initiators of a tighter connected soil food web which restores the closed carbon and nutrients cycles in soils, thereby accommodating species-rich plant communities in grasslands. Boosting the fungal channel as a bottom-up approach could thus be used as a next-generation restoration measure. We show data of soil inoculation experiments and trace the progression of change in the fungal community via sequencing and functioning via community response profiles. We assessed the top-down foraging of predators and consumers on the microbiome by analysing gut contents of consumers and predators from different restoration stages. We will be able to show preliminary data on the effect of fungi and their higher trophic levels in stimulating species-rich plant communities as well as give a prospect on the wider applications for microbiome engineering.
Magnetopause Shadowing Characteristics in Phase Space Density Measurements
Authors: Staples Frances , Rae Jonathan , Kellerman Adam , Murphy Kyle , Sandhu Jasmine , Forsyth Colin
Published: March 2021

Loss mechanisms act independently or in unison to drive rapid loss of electrons in the radiation belts. Electrons may be lost by precipitation into the Earth’s atmosphere, or through the magnetopause into interplanetary space. Whilst this magnetopause shadowing is well understood to produce dropouts in electron flux, it is less clear if shadowing continues to remove particles in tandem with electron acceleration processes, limiting the overall flux increase. 

We investigate the contribution of shadowing to overall radiation belt fluxes throughout a geomagnetic storm in early September 2017. We use new, multi-spacecraft phase space density calculations to decipher electron dynamics during each storm phase and identify features of magnetopause shadowing during both the net-loss and the net-acceleration storm phases. We also highlight two distinct types of shadowing; ‘Indirect’, where electrons are lost through ULF wave driven radial transport towards the magnetopause boundary, and ‘direct’, where electrons are lost as their orbit intersects the magnetopause. 
Recurrent landslides in Southern Western Ghats, India: A changing environmental perspective
Authors: Achu Asokan Laila , Gopinath Girish
Published: March 2021

The Western Ghats (WG), an elevated passive continental margin along the southwestern coast of India, is the most widely populated biodiversity hot spot in the world. Monsoon climate is prevalent throughout the length of the Western Ghats. The WG region is prone to the occurrence of various hydro-climatic disasters such as extreme rainfall-driven floods and landslides. During the past 100 years, landslides and floods caused by extreme rainfall events in the WG have occurred in 1924 and 1979; but the most disastrous event, in terms of area of impact, loss of life and economic impact, occurred in August 2018. Generally, the south-west monsoon (Indian summer monsoon) occurs in the first week of June and extends up to September and the Indian Meteorological Department (IMD) predicted above-normal rainfall of 13% during the month of August 2018. But the State received an excess of 96% during the period from 1st to 30th August 2018, and 33% during the entire monsoon period till the end of August. The unprecedented heavy rains, storms, floods and associated thousands of landslides have caused exorbitant losses including 400 life losses, over 2.20 lakh people were displaced, and 20000 homes and 80 dams were damaged or destructed. This study aimed to elucidate the reasons behind the thousands of landslides caused in WG using observed and field evidences. Changes in south-west monsoon pattern and rainfall intensity played a vital role in the occurrence of landslides in WG. Further, the extensive causalities are the result of anthropogenic disturbances including landscape alterations and improper landuse practices in the hilly tracks of WG. The major causative factors for series of landslides in various segments of WG is due to hindrance of lower order streams/springs, vertical cutting, intensive quarrying, unscientific rain pits & man-made structures together with erratic rainfall triggered major and minor landslides in various segments of WG. The present investigation concludes that a scientific landuse policy and geoscientific awareness is essential to mitigate the environment.
Using Rapid Repeat SAR Interferometry to improve Hydrodynamic Models of flood propagation in Coastal Wetlands 
Authors: Fagherazzi Sergio , Zhang Xiaohe , Jones Cathleen , Oliver-Cabrera Talib , Simard Marc
Published: March 2021

The propagation of tides and riverine floodwater in coastal wetlands is controlled by subtle topographic differences and a thick vegetation canopy. A precise quantification of fluxes of water, sediments and nutrients is crucial to determine the resilience and vulnerability of coastal wetlands to sea level rise. High-resolution numerical models have been used in recent years to simulate fluxes across wetlands. However, these models are based on sparse field data that can lead to unreliable results. Here, we utilize high spatial-resolution, rapid repeat interferometric data from the Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) to provide a synoptic measurement of sub-canopy water-level change resulting from tide propagation into wetlands.  These data are used to constrain crucial model parameters and improve the performance and realism of simulations of the Wax Lake wetlands in coastal Louisiana (USA). A sensitivity analysis shows that the boundary condition of river discharge should be calibrated first, followed by iterative correction of terrain elevation. The calibration of bed friction becomes important only with the boundary and topography calibrated. With the model parameters calibrated, the overall Nash-Sutcliffe model efficiency for water-level change increases from 0.15 to 0.53 with the RMSE reduced by 26%. More importantly, constraining model simulations with UAVSAR observations drives iterative modifications of the original Digital Terrain Model. In areas with dense wetland grasses, the LiDAR signal is unable to reach the soil surface, but the L-band UAVSAR instrument detects changes in water levels that can be used to infer the true ground elevation. The high spatial resolution and repeat-acquisition frequency (minutes to hours) observations provided by UAVSAR represent a groundbreaking opportunity for a deeper understanding of the complex hydrodynamics of coastal wetlands.
Quantifying spatial and seasonal variations of groundwater- surface water interaction for the prediction of hydrological turnover on the catchment scale
Authors: Bäthke Lars , Ulrich Sven , Schuetz Tobias
Published: March 2021

Targeting hypohreic exchange as well as gains and losses as the means of interaction between ground- and surface water in a stream leads forward to the consideration of both influencing the apparent hydrological turnover at the catchment scale i.e. the cumulative effect of gains and losses on physical water composition along a stream. The variability in hydrological turnover across a catchment is governed by the spatially varying connectivity between groundwater and the streambed. Especially under low flow conditions, expansion of turnover relative to stream flow is prominent and its spatial variability is intensified.

Studying the scaling behaviour of hydrological turnover processes, we measured hydrological turnover along two representative stream segments of about 500-600m length at a second order tributary to the river Mosel in Trier, western Germany by applying differential sault dilution gauging (after Payn et al., 2009) over 10 campaigns in summer and 7 in winter. Each stream reach represents a typical geomorphological setting in the catchment. The upstream reach is characterized by steep sloping terrain towards the stream with pastures and forest at higher elevations as the dominant land use. At the downstream reach the terrain is flatter with the stream meandering. The land use is diverse with meadow, pastures and forest as well as settlements. Each respective reach was split into two equidistant parts, resulting in three measurements of hydrological turnover, first and second section as well as the whole reach. Thus, acquiring data accounting for the spatial variability in each reach as well as between reaches. The measurements were carried out weekly, at the two stream reaches from August to September with stream flow ranging from ca. 2 l/s to 94 l/s and at the downstream reach from November to February with stream flow ranging from 200 l/s to over 1000 l/s.

The results show clearly the positive relationship between discharge and the relative volume of water exchanged between stream, hypohreic zone and groundwater as gains and losses at the reach scale. In addition to that, exchange processes vary independently at both investigated reaches. However, the dataset suggests a distinctive relationship between turnovers of an entire reach compared to the sum of the two sub-reach sections. The slope of this relationship may be a first step for the upscaling of observed exchange and turnover processes from the reach to the network scale.
A regime view of future atmospheric circulation changes in Northern mid-latitudes
Authors: Fabiano Federico , Meccia Virna L. , Davini Paolo , Ghinassi Paolo , Corti Susanna
Published: March 2021

Future changes in the mid-latitude wintertime atmospheric circulation are studied from a weather regimes perspective. The analysis is based on daily geopotential height at 500 hPa during the extended winter season (NDJFM) from both CMIP5 and CMIP6 historical and scenario simulations. The model performance in reproducing the observed weather regimes during the historical period in the Euro-Atlantic (EAT) and Pacific-North American (PAC) sectors is first evaluated, showing a general improvement of CMIP6 models in terms of regime patterns, frequencies and variance ratio. The projected circulation changes in the future climate (2050-2100) under the different scenarios are analysed in terms of the change in the frequency and persistence of the regimes. Significant positive trends are found for the frequency of NAO+ and negative trends for the Scandinavian Blocking and Atlantic Ridge regimes. This confirms the tendency for the zonalization of the circulation in the EAT sector, with decreased latitudinal variability of the jet stream. For the PAC sector, significant changes are seen for the Pacific Trough regime (increase) and the Bering Ridge (decrease), while there is no agreement in the response of the two PNA regimes. The spread among the model responses in the most extreme scenarios is analysed through a multi-linear regression approach and linked to different levels of warming in the polar stratosphere, the tropical upper troposphere, the North Atlantic and the Arctic.
A multistratigraphic study of the Campanian Postalm section (Northern Calcareous Alps, Austria)
Authors: Wagreich Michael , Wolfgring Erik , Hohenegger Johann , Dinarès-Turell Jaume , Spötl Christoph , Sames Benjamin
Published: March 2021

The Postalm section in the Gosau Group (Northern Calcareous Alps) exposes pelagic deposits of northwestern Tethyan origin. We present a magneto-, bio- and chemostratigraphic assessment of this Santonian to uppermost Campanian record, as well as a cyclostratigraphic model for the Tethyan Campanian based on three independently assessed proxies; the δ13C signature, the elemental ratio of Fe and the thickness of limestone/marl couplets (Wolfgring et al., 2021).

The Santonian/Campanian transition is characterised by condensed greyish packstones, the Campanian strata exhibit a succession of limestone-marl couplets that represent orbital precession of an approximate duration of 20ka. A magneto- and biostratigraphic (based on planktonic foraminifera and calcareous nannofossils) framework is supported by carbon isotope and strontium stratigraphy.

The Sr isotope record matches the data for the Upper Cretaceous and suggests no major gaps in the Postalm succession. A robust cyclostratigraphic assessment of three independently assessed data series (L/M couplets, Fe and δ13C) resulted in the identification of eighteen 405 ka eccentricity cycles spanning the middle to upper Campanian (Contusotruncana plummerae to Gansserina gansseri Zones or CC17/UC15 to CC23/UC16 nannofossil zones).

Carbon isotope stratigraphy identifies the LCE (Late Campanian Event) and possibly the SCBE (Santonian Campanian Boundary Event). Magneto- and biostratigraphic data, in particular the position of the top of the R. calcarata planktonic foraminifera Zone, the position of the LCE and the top of Chron C32r.1r served as primary tie points and constraints to match the floating cyclostratigraphic model to the Laskar solution and to compare it to other cyclostratigraphic solutions and reference sections for the upper Campanian.

References: Wolfgring, E., Wagreich, M., Hohenegger, J., Böhm, K., Dinarès Turell, J., Gier, S., Sames, B., Spötl, C., Jin, S., 2021. An integrated multi-proxy study of cyclic pelagic deposits from the north-western Tethys: The Campanian of the Postalm section (Gosau Group, Austria), Cretaceous Research, 120, 104704, doi.org/10.1016/j.cretres.2020.104704.
Elastic anisotropy of oceanic serpentinites – influence of CPO and microstructure
Authors: Kühn Rebecca , Behrmann Jan , Kilian Rüdiger , Leiss Bernd , Stipp Michael
Published: March 2021

Physical properties of rocks are mainly controlled by the modal composition, crystallographic preferred orientation (CPO) and microstructure of a rock. One of the most relevant physical properties related to the interpretation of seismic data are the elastic properties of a mineral aggregate. Changes of elastic properties - and hence changes in our interpretation of the tectonic architecture of certain regions - can be related to mineral reactions and deformation.

In order to explore the impact of mineral reaction and deformation on elastic anisotropy, we study oceanic serpentinites formed at low-grade metamorphic conditions by hydration of peridotites. Samples are obtained from the Atlantis Massif, which is an Oceanic Core Complex located at 30°N, Mid-Atlantic Ridge. During IODP Expedition 357, oceanic serpentinites were recovered from drill cores along the southern wall of the Massif. Fully serpentinized samples displaying variable microstructures were analyzed regarding the influence of microstructure and CPO on the overall elastic anisotropy. Microstructure analysis was based on optical microscopy and large area micro X-ray fluorescence mapping. For CPO analysis synchrotron high energy X-ray diffraction in combination with the Rietveld method was applied and the derived CPO was used to compute seismic properties.

Serpentinites with a typical mesh microstructure are interpreted to represent undeformed samples and show a close to uniform CPO. The increase in fabric anisotropy of vein-like magnetite aggregates is interpreted as an increase in deformation. Samples show a single c-axis-maximum and enhanced CPO. Calculated seismic anisotropies show up to >5% anisotropy for compressional waves (Vp) and shear wave splitting up to 0.15 km/s in the deformed samples. Hence, such an anisotropy can be used to differentiate deformed from undeformed zones in seismic data sets using the elastic anisotropy data.
Optically thin clouds in the winter trades
Authors: Mieslinger Theresa , Kölling Tobias , Brath Manfred , Stevens Bjorn , Buehler Stefan A.
Published: March 2021

We investigate the abundance and radiative effect of small and optically thin clouds in trade wind cumulus cloud fields from high-resolution satellite imagery. Using radiative transfer calculations to simulate clear-sky observations, we can identify optically thin cloud areas in ASTER images, a signal that is undetected by the satellite products that are commonly used for cloud radiative effect and cloud feedback analysis. Results from the analysis within the EUREC4A campaign suggest that the area covered by optically thin clouds is approximately as big as the area covered by clouds that are detected by common cloud masking algorithms. Compared to clear-sky ocean observations, the enhanced radiance from optically thin clouds leads to a high-bias in clear-sky estimates and hence a low-bias in the estimated radiative effect of trade wind cumuli. Next to the radiative effect, we discuss further implications that a broad cloud optical depth distribution might have on modelling results of a perturbed climate.
Integrating 1D-2D Hydrodynamic Model For Sabarmati Upper River Basin With Special Reference to Ahmedabad City Area
Authors: chandel sejal , shah suvarna
Published: March 2021

In recent study, Gujarat has become one of the India’s most urbanized state, causing severe flash flooding. The Sabarmati river is one of the major west-flowing rivers in India and biggest river of north Gujarat.Urbanization should meet the population’s need by enlargement of paved areas, which has unusually changed the catchment’s hydrological and hydraulic characteristic. Therefor, the frequency of flash flooding in Sabarmati river has been increased. The Sabarmati river basin experienced eight times devastating flooding coendition between 1972 to 2020.Among which July 2017 flooding event breakdown a 112 years old record of 1905. The Dharoi dam and Wasna barrage on Sabarmati river and surrounding district Kheda, Mehsana, Gandhinagar, Ahmedabad received a huge rainfall caused anomalous inflow to tributary which forced the dam authorities to release huge discharge in short duration which leads to flooding. The Sabarmati riverfront of Ahmedabad had been going under water for five days due incessant rainfall in the city that leads to swelling of the Sabarmati river in 2017. In order to determine extent of Inundation, Hydrodynamic Model HEC-RAS(5.0.6) with Arc GIS was used. Various scenarios were run with HEC-RAS to study the impact of flow simulation on flood inundation(with & without riverfront project). The simulated flood depths have been compared with actual depths obtained at gauging station, which were collected from Government authorities. Ultimately, the analysis was used to create maps for different return periods with RAS Mapper and ArcMap that visually show the reach of the floodplains, illustrating the affected areas. Results demonstrate the usefulness of  modelling system to predict the extent of flood inundation and thus support analyses of management strategies to deal with risk associated with infrastructure in an urban setting.
Long-Wavelength Earth Model via Accelerated Full-Waveform Inversion
Authors: Thrastarson Solvi , van Herwaarden Dirk-Philip , Krischer Lion , van Driel Martin , Boehm Christian , Fichtner Andreas
Published: March 2021

As the volume of available seismic waveform data increases, the responsibility to use the data in an effective way emerges. This requires computational efficiency as well as maximizing the exploitation of the information associated with the data.

In this contribution, we present a long-wavelength Earth model, created by using the data recorded from over a thousand earthquakes, starting from a simple one-dimensional background (PREM). The model is constructed with an accelerated full-waveform inversion (FWI) method which can seamlessly include large data volumes with a significantly reduced computational overhead. Although we present a long-wavelength model, the approach has the potential to go to much higher frequencies, while maintaining a reasonable cost.

Our approach combines two novel FWI variants. (1) The dynamic mini-batch approach which uses adaptively defined subsets of the full dataset in each iteration, detaching the direct scaling of inversion cost from the number of earthquakes included. (2) Wavefield-adapted meshes which utilize the azimuthal smoothness of the wavefield to design meshes optimized for each individual source location. Using wavefield adapted meshes can drastically reduce the cost of both forward and adjoint simulations as well as it makes the scaling of the computing cost to modelled frequencies more favourable.
Ambipolar electrostatic field in negatively charged dusty plasma
Authors: Hadid Lina , Shebanits Oleg , Wahlund Jan-Erik , Morooka Michiko , Nagy Andrew , Farrell William M. , Holmberg Mika , Modolo Ronan , Persoon Ann , Tseng Wendy
Published: March 2021

It is well known that in the magnetosphere of the outer planets (eg. Saturn, Jupiter, Neptune), even in the absence of an electric current, a polarization electric field develops as a consequence of charge separation in a plasma, providing a restoring force to maintain charge neutrality. It is also well established that certain regions of these planetary systems (ionosphere, icy moons, rings) are populated by significant amount of charged dust that play an important role in the physical and chemical processes in the surrounding plasma environment.
In the present work, we study the effect of the charged dust grains on the polarization electric field using Saturn’s F-ring region as a case study. We derive a general expression for E parallel to the magnetic field (E_para) and then using the Cassini RPWS/LP measurements we estimate for the first time in situ E_para close to Janus/Epimetheus ring during the F ring grazing orbits. We further demonstrate that the presence of charged dust,  as small as nanometers in size, can significantly influence the plasma transport processes, in particular the ambipolar diffusion along the magnetic field lines. We show that, close to the ring plane (Z <0.1 Rs), the dusty plasma amplifies E_para by at least one order of magnitude and reverses its direction. Such a reversal implies a confinement of the electrons above the equatorial plane. Furthermore, we show a clear correlation between the amplification of the ambipolar eletrostatic field and the ions and electrons number densities, that could be used in other dusty environments where in-situ measurements are not available yet (in our solar system or the interstellar medium).
Surface deformation analysis in Northeast Italy by using PS-InSAR and GNSS data 
Authors: Areggi Giulia , Merryman Boncori John Peter , Pezzo Giuseppe , Serpelloni Enrico , Bonini Lorenzo
Published: March 2021

Geodetic data play a crucial role in the detection of surface deformation related to active tectonic processes. The present study aimed to investigate the Northeastern Italian sector, characterized by a convergent regime due to the NNW-ward motion of the Adria microplate towards the Eurasian plate, at a rate of ~ 2mm/yr. N-S shortening is accommodated by fold and thrust systems in the Alpine chain and buried below the Friuli-Venetian plain sediments. We used InSAR and GNSS data respectively in 2015-2019 and 2000-2020 time interval to estimate the surface kinematics and deformation pattern of the area. We processed the SAR images acquired by the European satellites Sentinel 1A/B from ascending and descending tracks by using the Stanford Method for Persistent Scatterers (StaMPS). A post-processing of the resulting Line-Of-Sight (LOS) deformation time series was carried out by applying a spatial-temporal filter and calibrating using the velocities provided by GNSS stations. Finally, the post-processed ascending and descending LOS measurements were combined to solve for the vertical and horizontal (east-west) deformation components. We observed a positive vertical signal toward the Alps, in the northern region of Veneto and Friuli-Venezia Giulia. Moreover, we observed a significant negative vertical signal located in the plain and in the coastal zones due to the subsidence that strongly affects these areas. Horizontal velocities with rate of 1-2 mm/yr are observed close to main tectonic structures, especially in the eastern and the northwestern sector of the study area, where GNSS data reveal higher shortening rate.
Diversity in ERC populations: applicants, grantees and reviewers
Authors: Jesus-Rydin Claudia , Fariña-Busto Luis
Published: March 2021

The European Research Council (ERC), Europe’s premiere funding agency for frontier research, views equality of opportunities as an essential priority and a vital mission to ensure credibility in the review process. The ERC monitors closely various demographic data yearly on every call and has taken actions to tackle imbalances and potential implicit and explicit biases.

This presentation is focused on demographic data for the three main funding schemes: Starting Grant, Consolidator Grant and Advanced Grant. Attention is directed mainly to gender and geographic distribution. The demographics presented here consider various stakeholders, such as reviewers, applicants and grantees.

After more than 10 years of existence, ERC data provides an insight on demographical evolution. In the first framework programme (FP7, 2007-2013), 25% of applicants were women. In the last years (Horizon 2020, 2014-2019), this percentage increased by 4%, with 29% of women applied for ERC grants. In the same periods of time, the share of women as grantees has also increased from 20% to 29%. In the last years, men and women enjoy equal success rates. This presentation also sheds light on the population diversity of ERC reviewers, both panel members and external reviewers.

The ERC knows that work to ensure equality of opportunities is never finished. This presentation analyses critically the institutional efforts and considers possible steps to consolidate the accomplished results.
The contribution of different climate forcings on the global glacier climatic mass balance over the last millennium
Authors: Vlug Anouk , Maussion Fabien , Marzeion Ben , Prange Matthias , Richter Kristin
Published: March 2021

The mass loss of glaciers and ice caps is one of the major contributors to sea-level rise over the past 120 years. Different climate forcings, both natural and anthropogenic, have an influence on the climate and therefore on glacier mass balance. Glaciers have a slow and delayed response to climate change, and at any point in time, their properties are therefore also a result of past climate changes. In this context, we present global glacier simulations over the last millennium. For these simulations, the Open Global Glacier Model was forced with the fully forced, single forced and control simulations of the Community Earth System Model Last Millennium Ensemble. These simulations show how different climate forcings, i.e., volcanic, greenhouse gasses, solar, orbital, land use & land cover and ozone-aerosol, impact the climatic mass balance, both individually and combined. These influences are then analyzed over time and regionally. In addition to addressing the role of the different forcings, we present the contribution of natural vs anthropogenic forcings on glacier mass balance over the last millennium.
Lacustrine oxygen isotope records from biogenic silica (δ18OBSi) – a global compilation and review
Authors: Meister Philip ,   Project team: "Lacustrine oxygen isotope records from biogenic silica (δ18OBSi) – a global compilation and review"
Published: March 2021

Isotope records are crucial for proxy-model comparison in paleoclimatology because of their advantage of being directly comparable with isotope-enabled paleoclimate model outputs. Oxygen isotopes (δ18O) are commonly measured on carbonates (i.e. ostracods, authigenic carbonates) and biogenic silica (mainly diatoms). Oxygen isotopes in lacustrine carbonates (δ18OCaCO3) have been studied extensively for several decades, yet they are subject to complex species-dependent fractionation processes and not available globally. Lacustrine oxygen isotope records from biogenic silica (δ18OBSi), on the other hand, likely do not display species-dependent fractionation effects (or only very minor) and offer insight even in data-sparse regions devoid of carbonates, such as the Arctic. To date, more than 70 lacustrine δ18OBSi records have been published. These case studies have been complemented with additional efforts addressing climatic and hydrological backgrounds, laboratory techniques and possible species-dependent fractionation as well as deposition and dissolution effects.

Here, we present the first comprehensive review and global compilation of lacustrine δ18OBSi records, with explicit regard to their individual lake basin parameters. With this work, we aim at contributing to bridging the gap between modelling and isotope geochemistry approaches regarding terrestrial archives in paleoclimatology. Departing from hitherto prevalent case studies, we assess what we can learn from lacustrine δ18OBSi records globally, considering lake basin characteristics, spatial and temporal coverage as well as hydrological background information. This improves both the usability of δ18OBSi for proxy-model comparison and our understanding of the general constraints for interpreting lacustrine δ18OBSi records.
The link between the drop scale, high resolution measurements and precipitation estimates at the catchment scale
Authors: Lanza Luca G. , Cauteruccio Arianna
Published: March 2021

In-situ liquid precipitation measurements are the essential source of information about the rainfall process, its spatiotemporal variability, and the expected frequency of intense events. Other sources are remote sensors or the measurement of hydrologically connected variables, such as the water flow in rivers or evaporation, but all these only provide indirect estimates of precipitation. Notwithstanding the advantage of allowing areal estimates, they still require accompanying in-situ measurements for calibration or validation purposes.

The accuracy of in-situ precipitation measurements, though understated in most research studies and hydrological applications, is imperative to substantiate both scientific achievements and decision making. Unfortunately, due to budgetary shortages and other priorities, the managers of monitoring networks rarely address accuracy and traceability issues to a significant extent, and measurements are performed at a much lower level of accuracy than the current scientific knowledge and technological development would actually permit.

The neglected precipitation measurement biases propagate through the applications or the modelling chain and their awareness is often rapidly lost, together with the reliability of the obtained results. The comparability and homogeneity of precipitation estimates and their hydrological consequences between different studies is also questionable.

High-resolution measurements, even down to the scale of the single drop, are the way to achieve better knowledge of the precipitation process and to raise the confidence of users in the accuracy of their basic source of information. In this work, based on the most recent results in precipitation measurement studies, we aim at demonstrating that the accuracy of catchment scale rainfall and snowfall estimates rely on the interpretation of high-resolution raw data from traditional sensors and on the knowledge of the drop size distribution and other microphysical parameters of the rainfall process. Drop scale measurements must be accurate as well, and this is still an open issue for the currently available disdrometers.
Expert Perspectives & Methodological Excerpts: Stitching a thesis quilt
Authors: Neenan Emer Emily
Published: March 2021

Much like many crafted items, research must be functional and fit for purpose, but there's no reason why it can't also be beautiful, creative, and expressive.

In working with teenagers and young people on geoscience education and climate literacy, it became increasingly important to me to find ways to express my research that would connect with people who didn't have a foundation (yet, or at all) in academic discourse. My PhD thesis is therefore written as a creative semi-fictional epistolary; a collection of documents that tell the story of the research from the first tentative proposal to my would-be supervisor, to the final submission. I made the choice to produce a creative thesis for my student co-researchers and other readers, but the person who benefitted most from it was me. The creative process in designing my thesis was fulfilling, fun, and facilitated a deeper and more meaningful engagement with my own research. 

In discussing my thesis with another researcher, trying to explain how and why I was writing geoscience education research through annotations and poems and chatlogs, I suggested the metaphor of a quilt. A quilt is inherently a functional object that must meet certain qualifying standards in order to be accepted and used. But also, a quilt can be an intricately crafted artwork, reflective not just of its use, but of the person who makes it; their choices, their joys, their cares. As a quilt is an artwork with a specific useful function of keeping someone warm at night, so too a thesis (or paper or project) can be artistic and creative while also still having useful functions of building knowledge, generating data, or developing theory. 

So, long story short, I also sewed a thesis quilt, to express both the process and outcome of my doctoral research as a piece of fabric art!
Overcoming the challenges of increasing resolution and complexity in GEOS
Authors: Putman William
Published: March 2021

The NASA Global Earth Observing System (GEOS) model supports an array of complex Earth system simulation and assimilation capabilities.  These range from simple development frameworks such as dry atmosphere dynamics and single column physics cases, to fully coupled atmosphere-ocean-land-cryosphere-chemistry. Efficient use of available computational resources requires extensive scientific development within each of these components, and optimized frameworks for coupling and executing these components in a comprehensive manner.  Ultimately, experiment design requires a compromise between complexity and increased resolution.  This talk will explore these compromises within the array of global DYAMOND Phase II winter 40-day simulations completed with GEOS. These include: 1) A coupled 4km ocean and 6km atmosphere with interactive two-moment aerosol cloud microphysics. 2) A 3km 181-level atmosphere with single-moment 6-phase cloud microphysics including 1km global carbon emissions for chemistry transport. 3) A 1.5km 181-level atmosphere with simple parameterized chemistry.
An evaluation of rainfall regime changes in Italy over the last decades from literature
Authors: Caporali Enrica , Lompi Marco , Pacetti Tommaso , Chiarello Valentina , Fatichi Simone
Published: March 2021

The growing attention to modifications in climate in several societal sectors has led to an increasing number of studies and research on the topic of climate change and especially on changes in precipitation. The analysis presented here draws a “state of the art” of changes in the Italian precipitation regime through the review of the most relevant published studies, in peer-review journals. The aim of the study is to summarize a large quantity of information derived from specific studies, in a unique analysis and to highlight the main patterns of rainfall changes in Italy in the last decades. The results of 54 selected studies are discussed through the introduction of a weight factor, which considers the importance of each study according to its geographical area, stations density, and time series length, and provides a quantitative evaluation of the review. To offer a coherent climatic classification of the review findings, Italy is subdivided in three main macro areas and studies are also subdivided in 3 groups according to the Time-Series Length: Short TSL, less than 65 years; Long TSL, until 100 years; and centennial TSL, over 100 years. The analysis is focused on the Total Precipitation (TP) and the number of Wet Days (WDs) indices at the annual and seasonal scale. Looking at the overall results of the review, most of the studies agree about a decrease at the annual scale of the Wet Days index throughout the Italian territory for short and centennial TSL. The reduction of precipitation is confirmed by the Total Precipitation index that at the annual scale reflects this tendency except for the Northern Italy. This feature also emerges from the seasonal analysis, with some heterogeneity in the results due to difference in the number of studies used in the various areas, suggesting that there is an underlying climatic pattern driving trends toward a reduction in wet days and rainfall over the Italian territory.
Probability of distributed surface rupturing occurrence and displacement regression for dip-slip earthquakes
Authors: Nurminen Fiia , Visini Francesco , Baize Stéphane , Boncio Paolo , Pace Bruno , Scotti Oona , Valentini Alessandro
Published: March 2021

Probabilistic fault displacement hazard analysis (PFDHA) estimates the probability of occurrence and the expected exceedance of on-fault (principal fault rupturing; PF) and off-fault (dist ributed rupturing; DR) surface displacement during an earthquake. Here we concent rate on off-fault rupturing on dip-slip earthquakes, and present an original probability model for the occurrence of DR and for the expected exceedance of displacement dist ribution based on an approach named “slicing” (an alternative to the “gridding” approach commonly used). The method is developed based on the compilation and reappraisal of surface ruptures from 32 historical crustal dip-slip earthquakes, with magnitudes ranging from Mw 4.9 to 7.9. A ranking scheme is applied to distinguish PF (rank 1) from simple DR (rank 2) and t riggered faulting (rank 3). Thus modellers can use prediction equations based on or excluding ruptures st rongly related to local st ructural setting depending on the site of concern. In the case of a st ructural setting at a site where large-scale bending (rank 21, 22) and pre-existing faults (rank 1.5, 3) is considered irrelevant, modelling can be performed considering only the unpredictable DR (rank 2). To minimize bias due to the incomplete nature of the database, we int roduce the “slicing” approach, which considers that the probability of having a surface rupture within slices parallel to the PF is homogeneous along the st rike of each slice. “Slicing” probabilities, computed as a function of magnitude of the earthquake and distance from the PF, are then combined with Monte Carlo simulations that model the dependence of the probability of occurrence of rupture and exceedance of displacement with the dimensions and position of the site of interest with respect to the PF. Finally, both probabilities are combined with existing predictive equations of exceedance of displacement on the PF to calculate fault-displacement hazard curves for sites of interest.
Characterizing housing stock vulnerability to floods by combining UAV, Mapillary and survey data – A case study for Karonga, Malawi
Authors: Gortzak Inez , van den Homberg Marc , Margutti Jacopo , Beddow Christopher , van Aalst Maarten
Published: March 2021

To accurately identify the most vulnerable areas to floods, physical (e.g., building material) and social (e.g., education, health, income of households) housing stock information is required. However, in developing countries, this information is often unreliable, unavailable or inaccessible, and manual data collection is time-consuming. This can lead to difficulties for humanitarians or policymakers in implementing appropriate disaster risk reduction and response interventions. Therefore, there is a need for the development of alternative approaches to data collection and analysis. An alternative approach to on-site vulnerability assessment is to extract physical vulnerability characteristics, such as land use type or rooftop material, from satellite or Unmanned Aerial Vehicle (UAV) imagery. However, other social or physical vulnerability information on the household level can often not be extracted from only the remote sensing data. This research develops an approach for integrating multiple data sources into a Geographic Information System to improve the completeness of data on different vulnerability indicators. This approach is applied on the housing stock of the Karonga district in Malawi. An Object-Based Image Analysis on UAV imagery is combined with a machine learning analysis of Mapillary data to enable remote identification of both rooftop ànd wall material. Depth-damage curves were created to describe the impact on the housing stock for different categories of physical vulnerability (such as building material) and levels of inundation. Moreover, local survey data is used for the creation of a social vulnerability index. Combined, the datasets represent the spatial distribution of housing stock vulnerability for multiple flood scenarios. This approach is useful in situations where proactive risk analyses must be carried out or where local-scale interventions, such as building strengthening- or flood awareness projects, have to be implemented. Finally, we give recommendations for scaling the methodology to areas where only lower resolution data is available.