ALBERT

Description: Volcanic island sector collapses have the potential to trigger devastating tsunamis and volcanic eruptions that threaten coastal communities and infrastructure. Considered one of the most hazardous volcano‐tectonic regions in the world, the Christiana‐Santorini‐Kolumbo Volcanic Field (CSKVF) lies in the South Aegean Sea in an active rift zone. Previous studies identified an enigmatic voluminous mass‐transport deposit west and east of Santorini emplaced during the early evolution of the edifice. However, the distribution and volume as well as the nature and emplacement dynamics of this deposit remained unknown up to now. In this study, we use an extensive dataset of high‐resolution seismic profiles to unravel the distribution and internal architecture of this deposit. We show that it is located in all basins surrounding Santorini and has a bulk volume of up to 125 km3, thus representing the largest known volcanic island mass‐transport deposit in the entire Mediterranean Sea. We propose that the deposit is the result of a complex geohazard cascade that was initiated by an intensive rift pulse. This rifting event triggered a series of smaller precursory mass‐transport events before large‐scale sector collapses occurred on the northeastern flank of the extinct Christiana Volcano and on the southeastern flank of the nascent Santorini. This was followed by the emplacement of large‐scale secondary sediment failures on the slopes of Santorini, which transitioned into debris and turbidity flows that traveled far into the neighboring rift basins. Following this cascade, a distinct change in the volcanic behaviour of the CSKVF occurred, suggesting a close relationship between crustal extension, mass transport and volcanism. Cascading geohazards seem to be more common in the evolution of marine volcanic systems than previously appreciated. Wider awareness and a better understanding of cascading effects are crucial for more holistic hazard assessments.

Description: Schematic Reconstruction of the Santorini Mass‐Transport Cascade (SMTC): After a phase of volcanic quiescence (A), a rift pulse (B) triggered precursory mass‐wasting events (C), large‐scale sector collapses (D) and secondary sediment failures (E), which culminated in a change in the volcanic behaviour of the system (F).

Description: Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659

Description: Empirical evidence demonstrates that lakes and reservoirs are warming across the globe. Consequently, there is an increased need to project future changes in lake thermal structure and resulting changes in lake biogeochemistry in order to plan for the likely impacts. Previous studies of the impacts of climate change on lakes have often relied on a single model forced with limited scenario-driven projections of future climate for a relatively small number of lakes. As a result, our understanding of the effects of climate change on lakes is fragmentary, based on scattered studies using different data sources and modelling protocols, and mainly focused on individual lakes or lake regions. This has precluded identification of the main impacts of climate change on lakes at global and regional scales and has likely contributed to the lack of lake water quality considerations in policy-relevant documents, such as the Assessment Reports of the Intergovernmental Panel on Climate Change (IPCC). Here, we describe a simulation protocol developed by the Lake Sector of the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP) for simulating climate change impacts on lakes using an ensemble of lake models and climate change scenarios. The protocol prescribes lake simulations driven by climate forcing from gridded observations and different Earth system models under various Representative Greenhouse Gas Concentration Pathways, all consistently bias-corrected on a 0.5° × 0.5° global grid. In ISIMIP phase 2, 11 lake models were forced with these data to project the thermal structure of 62 well-studied lakes where data were available for calibration under historical conditions, and for nearly 17,500 lakes using uncalibrated models and forcing data from the global grid where lakes are present. In ISIMIP phase 3, this approach was expanded to consider more lakes, more models, and more processes. The ISIMIP Lake Sector is the largest international effort to project future water temperature, thermal structure, and ice phenology of lakes at local and global scales and paves the way for future simulations of the impacts of climate change on water quality and biogeochemistry in lakes.

Description: Das Ziel der Energiewende - ein sicheres, umweltverträgliches und ökonomisch erfolgreiches Energiesystem - birgt diverse Herausforderungen. Diese umfassen die Erreichung der Klimaneutralität, den Umstieg auf erneuerbare Energieträger in allen Sektoren (inkl. Schwerlast- und Flugverkehr sowie industrielle Prozesswärme) als auch deren gegenseitige Integration. Bioenergie kann hierzu einen multiplen Beitrag leisten, sowie negative Emissionen bereitstellen und darüber hinaus auch Beiträge jenseits des Energiesystems erbringen, wie Naturschutz, ländliche Entwicklung, oder die Bereitstellung von biogenem CO2 als Rohstoff für die chemische Industrie. Somit ist Bioenergie ein unverzichtbarer Bestandteil für die Lösung der Herausforderungen in der Transformation zu einem nachhaltigen Energiesystem. Gegenwärtig stellt Bioenergie mit dem größten Anteil an erneuerbaren Energien im Primärenergieverbrauch (60 %) als auch im Endenergieverbrauch (53 %), mehr als alle anderen erneuerbaren Energieträger zusammen. Dabei bestehen Unterschiede zwischen den Endenergiesektoren: während Bioenergie in der Bruttostromerzeugung 24 % des erneuerbaren Stroms deckt, dominiert sie die erneuerbare Bereitstellung von Wärme mit 86 % als auch den erneuerbaren Endenergieverbrauch im Verkehrssektor mit 88 % in 2018. Aufgrund der Bedeutung von Bioenergie heute werden Beispiele vorgestellt, welche einen zukünftigen multipleren Systembeitrag von Bioenergie fokussieren.

Description: The following authors were omitted from the original version of this Data Descriptor: Markus Reichstein and Nicolas Vuichard. Both contributed to the code development and N. Vuichard contributed to the processing of the ERA-Interim data downscaling. Furthermore, the contribution of the co-author Frank Tiedemann was re-evaluated relative to the colleague Corinna Rebmann, both working at the same sites, and based on this re-evaluation a substitution in the co-author list is implemented (with Rebmann replacing Tiedemann). Finally, two affiliations were listed incorrectly and are corrected here (entries 190 and 193). The author list and affiliations have been amended to address these omissions in both the HTML and PDF versions. © 2021, This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply.

Description: We perform a teleseismic P-wave travel-time tomography to examine the geometry and structure of subducted lithosphere in the upper mantle beneath the Alpine orogen. The tomography is based on waveforms recorded at over 600 temporary and permanent broadband stations of the dense AlpArray Seismic Network deployed by 24 different European institutions in the greater Alpine region, reaching from the Massif Central to the Pannonian Basin and from the Po Plain to the river Main. Teleseismic travel times and travel-time residuals of direct teleseismic P waves from 331 teleseismic events of magnitude 5.5 and higher recorded between 2015 and 2019 by the AlpArray Seismic Network are extracted from the recorded waveforms using a combination of automatic picking, beamforming and cross-correlation. The resulting database contains over 162 000 highly accurate absolute P-wave travel times and travel-time residuals. For tomographic inversion, we define a model domain encompassing the entire Alpine region down to a depth of 600 km. Predictions of travel times are computed in a hybrid way applying a fast TauP method outside the model domain and continuing the wave fronts into the model domain using a fast marching method. We iteratively invert demeaned travel-time residuals for P-wave velocities in the model domain using a regular discretization with an average lateral spacing of about 25 km and a vertical spacing of 15 km. The inversion is regularized towards an initial model constructed from a 3D a priori model of the crust and uppermost mantle and a 1D standard earth model beneath. The resulting model provides a detailed image of slab configuration beneath the Alpine and Apenninic orogens. Major features are a partly overturned Adriatic slab beneath the Apennines reaching down to 400 km depth still attached in its northern part to the crust but exhibiting detachment towards the southeast. A fast anomaly beneath the western Alps indicates a short western Alpine slab whose easternmost end is located at about 100 km depth beneath the Penninic front. Further to the east and following the arcuate shape of the western Periadriatic Fault System, a deep-reaching coherent fast anomaly with complex internal structure generally dipping to the SE down to about 400 km suggests a slab of European origin limited to the east by the Giudicarie fault in the upper 200 km but extending beyond this fault at greater depths. In its eastern part it is detached from overlying lithosphere. Further to the east, well-separated in the upper 200 km from the slab beneath the central Alps but merging with it below, another deep-reaching, nearly vertically dipping high-velocity anomaly suggests the existence of a slab beneath the eastern Alps of presumably the same origin which is completely detached from the orogenic root. Our image of this slab does not require a polarity switch because of its nearly vertical dip and full detachment from the overlying lithosphere. Fast anomalies beneath the Dinarides are weak and concentrated to the northernmost part and shallow depths. Low-velocity regions surrounding the fast anomalies beneath the Alps to the west and northwest follow the same dipping trend as the overlying fast ones, indicating a kinematically coherent thick subducting lithosphere in this region. Alternatively, these regions may signify the presence of seismic anisotropy with a horizontal fast axis parallel to the Alpine belt due to asthenospheric flow around the Alpine slabs. In contrast, low-velocity anomalies to the east suggest asthenospheric upwelling presumably driven by retreat of the Carpathian slab and extrusion of eastern Alpine lithosphere towards the east while low velocities to the south are presumably evidence of asthenospheric upwelling and mantle hydration due to their position above the European slab.

Description: This dataset provides results from rheological tests of glucose syrup from two suppliers tested within the EPOS Multi-scale Laboratories (MSL) trans-national access (TNA) program 2019 at the Laboratory of Experimental Tectonics (LET), Univ. Roma TRE, Italy. Syrups Glucowheat 45/81 (GW45) and Glucowheat 60/79 (GW60) are produced by Blattmann Schweiz AG, Switzerland (2019 batch). Syrups GlucoSweet 44 (GS44) and GlucoSweet 62 (GS62) are produced by ADEA (Amidi Destrini ed Affini), Italy (2019 batch) . The four tested glucose syrups are labeled according to their DE value (dextrose equivalent value). For tested products from Blattmann Schweiz AG, the second number refers to the weight percentage of dry substance. Glucose syrup GS44 is used in full lithospheric scale analogue experiments at the Tectonic Modelling Lab (TecLab) at the University of Bern, Switzerland as a low-viscosity material simulating the asthenospheric mantle lithosphere to provide isostatic equilibration. The materials have been analyzed using a MCR301 Rheometer (Anton Paar) equipped with parallel plates geometry and rotational regime . To prevent the evaporation of the samples during the measurements, an external water-lock device has been used.

Description: This dataset includes surface 3D stereoscopic Digital Image Correlation (3D stereo DIC) images and videos of 9 analogue models on crustal scale rifting with a rotational component. Using a brittle-viscous two-layer setup, the experiments focused on near-surface fault growth, rift segment interaction and rift propagation. All experiments were performed at the Tectonic Modelling Laboratory of the University of Bern (UB). All models consist of a two-layer brittle-viscous set up with a total thickness of 6 cm. Thickness variations in ductile and brittle layers are expressed by the ratio RBD = brittle layer thickness/ductile layer thickness, which ranges from RBD = 1 to RBD = 3. The model set up lies on top of a 5 cm thick foam base with a trapezoidal shape with a height of 900 mm and a pair of bases of 310 mm and 350 mm. The foam block is sliced into segments such that 7 interlayered 0.5 cm thick plexiglass bars prevent foam collapse under the model weight. The foam base is initially compressed between the longitudinal side walls and homogeneously expands during the rotational opening. Applied velocities refer to the divergence of the sidewalls at the outermost point (i.e., furthest away from the rotation axis) and decrease linearly towards the rotation axis. These velocities vary from 10 mm/h over a total run time of 4 h up to 40 mm/h over a total run time of one hour, resulting in identical total extension of ca 13% (given an initial model width of 31 cm) for all models. Detailed descriptions of the experiments as well as monitoring techniques can be found in Schmid et al. (2021).

Description: This data set includes the results of digital image correlation of ten brittle-viscous experiments on crustal extension and four benchmark experiments performed at the Tectonic Modelling Lab of the University of Bern (UB). The experiments demonstrate the differences in rift development in orthogonal versus rotation extension. Detailed descriptions of the experiments and monitoring techniques can be found in Zwaan et al. (2019) to which this data set is supplementary. Additional background information concerning the general modelling approach are available in Zwaan et al. (2016).. The data presented here consist of movies displaying digital image correlation (DIC) derived surface and internal displacement fields as well as profiles of the lateral cumulative surface displacements. Digital photographs of the experimental surface and digital image cross section of the computed CT-scans were analyzed with DIC (Adam et al., 2005, 2013) techniques to quantify displacements in the image plane at high precision (〈0.1 mm). DIC was undertaken with the software DaVis 8.0 (LaVision) applying 2D-DIC (FFT-legacy) multipass processing with a final interrogation window size of 32x32 (CT: 12x12) pixels and 50% (CT: 25%) overlap.