bluuebunny/crossref_metadata_2025 huggingface dataset:
On Lagrangian particles tracking in coastal areas: hydrostatic vs non-hydrostatic model runs
Authors: Sokolov Alexander
Published: February 2023

This work is focussed on modelling of the hydrodynamic processes in small coastal areas using a 3-D model on unstructured mesh with fine spatial resolution. A finite element based three-dimensional baroclinic model TELEMAC-3D was applied to the Himmerfjärden area in the Baltic Sea. The TELEMAC modelling suite is developed by the National Laboratory of Hydraulics and Environment (LNHE) of Electricité de France (EDF).Himmerfjärden is a coastal fjord-like bay situated in the north-western part of the Baltic Sea. The fjord size is 25km by 50km and it has a mean depth of 17m and a maximum depth of 52m. The water is brackish (6‰) with small salinity fluctuation (±2‰). A sewage treatment plant, which serves about 300 000 people, discharges into the inner part of Himmerfjärden.The modelling domain is approximated by unstructured mesh with element size varying from 50m along the coast to 300m offshore. In vertical direction 20 sigma layers were used. The area was modelled operationally for five days period using model in hydrostatic and non-hydrostatic modes. Open boundary conditions were obtained from the Baltic wide NEMO v4.0 model operationally running by SMHI and provided by the Copernicus Marine Service. Meteorological forecast data were obtained using Open-Meteo API (https://open-meteo.com). Lagrangian particles were tracked online with and without stochastic diffusion.The computations were enabled by resources provided by the Swedish National Infrastructure for Computing (SNIC) at the NSC - National Supercomputer Centre at Linköping University, partially funded by the Swedish Research Council through grant agreement no. 2018-05973.
Evaluating the Role of Blockage Ratio and Orientation in the Drag Force Calculation for Large Woody Debris
Authors: Balmes Jan Peter
Published: February 2023

Large woody debris (LWD) is commonly used in river restoration projects because it provides important habitats. However, when used in urban creeks and rivers, these structures must be designed and installed in a way that balances the needs for flood safety with the goals of ecological restoration. To ensure the stability of LWD during floods, engineers must consider a range of characteristics such as the size of the structure relative to the flow cross-section, the ratio of length to diameter, shape, orientation, flow magnitude, and the overall hydraulic conditions. To properly design and fixate LWD, it is necessary to consider both lift and drag forces in different flow situations. There are several approaches available for calculating these forces, but many of them are often only applicable by simplifying the LWD into an idealized 1D or 2D cylinder case.The general drag force equation uses an empirical drag coefficient, which is a function of the object's shape, size, and surface roughness, as well as the properties of the fluid and the flow conditions. However, the drag coefficient does not account for factors such as blockage ratio (the ratio of the object's area to the flow cross-section) and orientation (the angle at which the object is oriented relative to the flow direction). These factors can significantly affect the drag force, and their inclusion in the drag force calculation can lead to more accurate predictions.To evaluate the role of blockage ratio and cylinder orientation, experiments were conducted in a 10 meter long, 79 cm wide glass flume with a rough bed to create a fully turbulent velocity profile. Smooth PVC cylinders, representing the woody structures, were placed in the flume with rotation angles between 0 and 90 degrees relative to the flow. Examined were three cylinders with a ratio of length to diameter from 3.16 to 9.48 and lengths between 20% and 60% of the channel width. A dynamic load cell was used to measure the drag forces on the cylinders in the flow direction, and various subcritical flow conditions with different depths and velocities were examined.
Developing geomagnetically induced current forecasting capability across Europe
Authors: Richardson Gemma , Beggan Ciarán , Wang Guanren , Florczak Ewelina , Clarke Ellen
Published: February 2023

Space weather poses a hazard to grounded electrical infrastructure such as power transmission networks, through the induction of geomagnetically induced currents (GIC). Modelling GIC in real-time, as well as historical events and extreme event scenarios is of great importance for understanding and mitigating the effects on power networks. We have constructed a model of the interconnected European power networks using open-source data, to provide estimates of GIC across the whole continent, with the goal of creating a real-time operational warning system.In recent years there have also been improvements in forecasting the ground geomagnetic field from L1 solar wind measurements using magnetohydrodynamic (MHD) models, and the development of models which forecast the solar wind itself days ahead of time. As part of the EUHFORIA2.0 Horizon 2020 project we have coupled models for the full Sun-to-Earth system to generate forecasts of geomagnetic fields, geoelectric fields and ultimately GIC across Europe.
An application of iterative principal component analysis on analyzing the regional groundwater level and stratum elastic-deformation
Authors: Chang Liang Cheng , Chen You Cheng , Lin Tsai Chen
Published: February 2023

The groundwater level is a comprehensive response of the external stimuli of the aquifer, such as rainfall and river recharge, and is one of the main factors affecting the formation deformation. The spatiotemporal analysis of stratum elastic deformation identifies different stimulus sources and their influence on groundwater level changes, as well as the influence of groundwater level changes on stratum elastic deformation. In addition to the numerical test to verify the correctness of the analysis process, this study uses the daily water level observation data of each aquifer in Yunlin area of Taiwan to conduct principal component analysis to explore the influence of rainfall and river water level on the variation of groundwater level in each aquifer. Furthermore, based on the magnetic ring layered subsidence observation well data, the iterative principal component analysis was used to explore the influence of the variation of the groundwater level in each layer on the elastic deformation of each layer.The research results show that the first principal component of the groundwater level in each aquifer in the Yunlin area can fully reflect the impact of rainfall on the groundwater level, and the residual water level affected by rainfall can be deducted to analyze the impact of the river water level. The results show that the shallower water level Compared with the deeper aquifers 2-2 and 3, layers 1 and 2-1 have a more significant effect on the river water level. In the analysis of formation compression deformation, the correlation analysis between the principal component of groundwater level and the principal component of formation deformation shows that there is a high negative correlation between the water level change of each aquifer and the formation deformation, which is in line with the physical mechanism of groundwater level and formation deformation. The above analysis results show that principal component analysis, combined with the analysis process of this study, can indeed identify and isolate the influence of various external stimuli to the groundwater level, and can also obtain the main changes in the elastic deformation of the formation, which can be used as the basis for further water resources planning and analysis. Important reference.
Quantifying the Downstream Impact of Implementing Irrigation in a Semi-Arid Mediterranean Basin in NE of Spain
Authors: Altés Víctor , Pascual Miquel , Escorihuela Maria José , Villar Josep Maria
Published: February 2023

Irrigation in arid and semi-arid regions is key to maintain the productivities and the well-being of farmers. However, irrigation is an important source of pollution to rivers due to the impact of agricultural drainage [1], which may contain high levels of salts, nutrients and other pollutants. In the present study we quantified the impact of implementing irrigation in a 10,000 ha semi-arid basin of the Noguera Ribagorçana river (Ebro Basin, NE Spain). Water quality data obtained during 20 years (2002-2022) in four different sampling points in the river (three before, and one after the main agricultural drainage returns of the basin, which drains 4,366 ha) were analyzed, focusing on nitrate concentration (NO3-, ppm), phosphate concentration (PO43-, ppm), and electrical conductivity of the water (EC, dS/m). In 2002, less than 4,000 ha were under irrigation and during the studied period, a total of 5,571 hectares were brought under irrigation progressively over time, with the implementation of a new irrigation district in the area. Results showed a significative difference in the concentration of NO3- in the river water before and after the main agricultural drainage return of the new irrigation district. However, phosphorous concentration and electrical conductivity showed no significative differences between the sampling points before and after the main agricultural drainage returns. On the other hand, NO3- values at the sampling point after the main agricultural drainage return have increased over time as it did the irrigated area. Thus, along the 18 km of the Noguera Ribagorçana river observed in this study, NO3- levels have increased on average from 1.7 ppm at the first sampling point to 10.9 ppm at the last sampling point, after the returns of agricultural drainage in the basin. Therefore, we could state that implementing irrigation in 5,571 ha represents an increase of 9.2 ppm of NO3- in the water of the Noguera Ribagorçana river in the studied area.[1] Blann, K. L.; Anderson, J. L.; Sands, G. R.; Vondracek, B. Effects of Agricultural Drainage on Aquatic Ecosystems: A Review. Crit. Rev. Environ. Sci. Technol. 2009, 39 (11), 909–1001. https://doi.org/10.1080/10643380801977966. 
Identifying and analyzing fog and low stratus life cycle regimes over central Europe
Authors: Pauli Eva , Cermak Jan , Andersen Hendrik
Published: February 2023

This contribution presents spatially distinct fog and low stratus (FLS) formation and dissipation regimes derived from satellite and reanalysis data and their sensitivities to meteorological and land surface conditions over central Europe.FLS formation and dissipation processes are strongly governed by meteorological and land-surface conditions and vary geographically and across seasons. The timing of FLS formation and dissipation further has implications for traffic and solar energy production. While climatological analyses of FLS formation and dissipation exist, the influence of meteorological and land surface conditions on specific FLS formation and dissipation regimes is not clear yet.In this study, satellite-derived fog and low stratus life cycle information is explicitly linked to land surface and meteorology in Europe. Pixel-based correlations of FLS formation and dissipation times with environmental conditions were analyzed in a hierarchical clustering approach. Spatially distinct regimes of FLS formation and dissipation can be identified, and a dependency on the background geography and climate is apparent. FLS formation and dissipation regimes are analyzed on multiple hierarchy levels, i.e. various cluster numbers are explored, to investigate the spatial division of larger regional regimes to smaller sub-regional and local regimes. Monthly mean sensitivities for selected sub-regional regimes suggest a dependency of those sensitivities on FLS type. A case study of a regime covering the Po valley in northern Italy is used to showcase the quantification of FLS drivers regionally using explainable machine learning. Future work will expand this approach to analyze and compare FLS drivers in regional regimes with different background geography and climate.
Digital twin computing for enhancing resilience of disaster response system
Authors: Koshimura Shunichi , Mas Erick
Published: February 2023

Digital twin is now recognized as digital copies of physical world's objects stored in digital space and utilized to simulate the sequences and consequences of target phenomena. By incorporating physical world’s data into the digital twin, developers and users have a full view of the target through real-time feedback. Recent advances in high-performance computing and large-scale data fusion of sensing and observations of both natural and social phenomena are enhancing applicability of digital twin paradigm to natural disaster research. Artificial intelligence (AI) and machine learning are also being applied more and more widely across the world and contributing as essential elements of digital twin. Those have significant implications for disaster response and recovery to hold out the promise of dramatically improving our understanding of disaster-affected areas and responses in real-time.A project is underway to enhance resilience of disaster response systems by constructing "Disaster Digital Twin" to support disaster response team in the anticipated tsunami disaster. “Disaster Digital Twin” platform consists of a fusion of real-time hazard simulation, e.g. tsunami inundation forecast, social sensing to identify dynamic exposed population, and multi-agent simulation of disaster response activities to find optimal allocation or strategy of response efforts, and achieve the enhancement of disaster resilience.To achieve the goal of innovating digital twin computing for enhancing disaster resilience, four preliminary results are shown;(1) Developing nation-wide real-time tsunami inundation and damage forecast system. The priority target for forecasting is the Pacific coast of Japan, a region where Nankai trough earthquake is likely to occur.(2) Establishing a real-time estimation of the number of exposed population in the inundation zone and clarifying the relationship between the exposed population and medical demand.(3) Developing a reinforcement learning-based multi-agent simulation of medical activities in the affected areas with use of damage information, medical demands, and resources in the medical facilities to fid optimal allocation of medical response.(4) Developing a digital twin computing platform to support disaster medical response activities and find optimal allocation of disaster medical services through what-if analysis of multi-agent simulation.
A new dataset of external surges in the German Bight and its application to potential high impact scenarios
Authors: Müller Alexander , Gerkensmeier Birgit , Gönnert Gabriele
Published: February 2023

External surges are a key component of extreme water levels in the North Sea. Caused by low pressure cells over the North Atlantic and amplified at the continental shelf, they can drive water level changes of more than one metre at the British, Dutch and German North Sea coast. To extend the knowledge on external surges, an automated approach to detect external surges was developed, using high resolution tide gauge data. The newly collected dataset of 101 external surges spanning from 1995 to 2020 revealed the phenomenon of series of external surges, whereat two or more external surges follow each other less than 72 h apart. This phenomenon accounts for 33% of the detected external surges. Serial events tend to occur more often during wind–induced storm surges. While the inclusion of external surges in design water levels is already applied in a few design level approaches, the effects of serial external surges on storm surges have not been studied. This presentation highlights past events of combined storm surges and serial external surges and analyses the corresponding storm tracks. Based on these events, modifications for further study are proposed, creating potential high impact events, which consist of storm surges combined with serial external surges.
Geoscience Access, Inclusion and… Belonging? Making Geoscience Degrees a Place of Belonging for All
Authors: Fox Bethany , Davidson Anna , Din Rukhsana , Patel-Nair Manju , Trowler Vicki
Published: February 2023

In the UK, the geosciences are one of the least diverse areas of science at all levels, from school through to senior professionals. This lack of diversity operates on a number of axes, including race, ethnicity, disability, and socioeconomic background. Both universities and learned societies have a range of initiatives to encourage students from under-represented groups to take up geoscience undergraduate degrees. However, merely increasing statistical representation is not sufficient for a truly ethical approach to diversity and inclusion. If we are to progress as a field, we must find ways to make geoscience undergraduate degrees feel like a place of belonging for all.  

We ran a series of workshops for current and recent undergraduates from under-represented groups in geoscience disciplines at UK universities. Groups represented included Black, Asian and minoritised ethnicity students; LGBTQIA+ students; disabled students; students from low-income backgrounds; students who were the first in their family to attend university; students from non-traditional educational backgrounds; international students; and students from a minoritised religious background. Most attendees identified as belonging to more than one of these groups. Geoscience disciplines represented by our attendees included geology, human and physical geography, environmental science and geochemistry.  

During the workshops, we asked participants to tell us about their experiences of geoscience undergraduate degrees and provide practical recommendations for improvements which would increase a sense of belonging. These recommendations covered a range of areas and most can be straightforwardly implemented by individual geoscience lecturers, although some require more institutional buy-in. Here we introduce the findings and recommendations, while full details are available at geoaccess.org.uk. 
Long-term response of the mountain cryosphere to climate change – a comparative perspective of the Andes of central Chile and the European Alps
Authors: Nussbaumer Samuel U. , García Juan-Luis , Gärtner-Roer Isabelle , Fernández Hans , Carraha Javiera , Pérez Francia , Tikhomirov Dmitry , Egli Markus
Published: February 2023

Over the last two decades the importance of the Andean cryosphere, particularly as water resource, has been recognized in both the scientific literature and the public sphere. However, in contrast to the European Alps, lack of field studies and limited knowledge regarding long-term cryosphere evolution has precluded basic knowledge for water-resource management and planning, particularly in the Andes of central Chile, a region that has been experiencing accelerated warming and a dramatic drought spell.Using detailed glacial geomorphological mapping as well as new geochronologic and geophysical data we unravel the ice evolution in four Andean basins: Río Limarí (31° S), Río Aconcagua (32° S), Río Maipo (33° S), and Río Rapel (34° S). The Andes of central Chile hide a striking mosaic of Quaternary landforms where climate, cryosphere, and tectonics converge. The findings from our analysis suggest glacier advances during the pre-last glacial period and the Last Glacial Maximum (LGM, ~26–17 ka), between 9–12 ka, ~2700 a cal BP, ~850 a cal BP, and ~600 years ago. Geomorphological evidence and geochronological data suggest at least two glacier advances to nearly the same extent, first by the 13th to 16th centuries and then by the early to mid-19th century. Since then, a gradual pattern of distinct moraine ridges as observed in several catchments denotes a rather active and gradual ice demise. A larger glacier extension than today is also documented during the first half of the 20th century.Finally, we discuss ages and their paleoclimate implications in the light of previous work in the region. Glacier chronologies in the southern mid-latitudes are suitable to track past latitudinal variability of the southern westerly winds (SWW) through the last glacial period and into the Holocene. For the latest Holocene, we note net humid and cold atmospheric conditions in central Chile between the 13th century and the mid-19th century. We conclude with an interhemispheric comparison of glacier chronologies from the Andes and the European Alps.
Coordinated observations for inner heliospheric science: contribution by the BepiColombo mission
Authors: Murakami Go , Benkhoff Johannes
Published: February 2023

In the 2020s we are entering a golden age of inner heliosphere science. International Mercury exploration mission BepiColombo was launched in 2018 and will arrive at Mercury in 2025. During the interplanetary cruise phase, BepiColombo will range from 1.2 AU to 0.3 AU, and will stay in the inner heliosphere for long time. BepiColombo started its science observations during the interplanetary cruise phase in 2020. The initial results showed its enough performance to observe solar wind electrons, IMF, and solar energetic particles (SEPs) even in the composite spacecraft configuration. Especially in 2021 two spacecraft of BepiColombo, Mercury Planetary Orbiter (MPO) and Mercury Magnetosphere Orbiter (Mio), successfully detected many SEP events. BepiColombo can contribute to leading and expanding the heliospheric system science. In addition to BepiColombo, NASA’s Parker Solar Probe and ESA’s Solar Orbiter are also exploring the inner heliosphere. Coordinated observations between these multi spacecraft have been planned and performed. In March 2021, we also coordinated a joint observation campaign of the solar corona and solar wind with BepiColombo, Akatsuki, and Hinode. These coordinated observations/analysis with multi spacecraft, ground-based observations, and numerical simulations can give us great opportunities to address outstanding questions in heliophysics. Here we Here we present the overview and updated status of BepiColombo and the coordinated science observations.
Seismic monitoring of co-eruptive volcanic processes during the 2021 Fagradalsfjall Eruption, Iceland, using two small-aperture arrays
Authors: Möllhoff Martin , Smith Patrick , Craig David , Bean Chris J. , Vogfjörd Kristin S. , Li Ka Lok , Nooshiri Nima
Published: February 2023

The 2021 Fagradalsfjall eruption in the Reykjanes peninsula, Iceland, was marked by episodes with varying volcanic activity. Our study focuses on the period from eruption start on the 19th March 2021 until the 2nd May 2021. This phase was marked by relatively continuous lava flows and non-periodic lava fountaining observed at up to 12 different vents, increasing in intensity throughout the observation period. Seismic tremor emanating from co-eruptive processes like for example lava fountaining, collapse of crater walls and magma and lava migration is non-impulsive, often with emergent onsets and no defined phase arrivals. Thus it is difficult to locate the tremor sources with traditional network based methods. We show that using small aperture arrays it is possible to locate and monitor several tremor sources that were active simultaneously, providing good spatial resolution on the details of the eruptive fissure. We investigate how array processing of 3-component data can assist with the determination of different seismic wave types and lead to a better understanding of the underlying volcanic processes. We find that seismic arrays are well suited to monitor the location, type and strength of volcanic processes that are active simultaneously. This can have important implications for volcanic hazard monitoring, especially when visual monitoring with webcams is difficult for example due to remoteness or poor visibility.
Dynamic weakening and rupture re-nucleation in rock gouge
Authors: Rubino Vito , Rosakis Ares , Lapusta Nadia
Published: February 2023

Many large and damaging earthquakes on mature faults in the Earth’s crust propagate along layers of rock gouge, the fine granular material produced by comminution during sliding. Characterizing gouge rheology is of paramount importance to improve our understanding of earthquake physics, as friction controls key processes of earthquakes, including nucleation, propagation and arrest and how damaging they can be.  In this work, we characterize friction evolution in rock gouge layers during the propagation of dynamic ruptures in a laboratory setting. The experimental setup features a hybrid configuration with a specimen made of an analog material and a rock gouge layer embedded along the interface. This configuration allows us to trigger dynamic ruptures due to the lower shear modulus of the analogue material while at the same time study the gouge frictional behavior during spontaneously evolving dynamic events. Ruptures are captured by the use of digital image correlation coupled with ultrahigh-speed photography. Our measurements reveal dramatic friction variations, with the gouge layer initially displaying strengthening behavior and inhibiting earthquake rupture propagation. However, the gouge layer later features dramatic frictional strength losses, and hosts rupture re-nucleation enabled by dynamic stressing and marked friction weakening at higher slip velocities. Our measurements of the weakening and strengthening behavior of friction in fine rock gouge illustrate the strong dependence of their rheology on slip velocity and related processes, including shear heating, localization/delocalization of shear, and dilation/compaction of the granular shear layer.
Investigation of the Influence of Stellar Particle Events and Galactic Cosmic Rays on the Atmosphere of TRAPPIST-1e
Authors: Bartenschlager Andreas , Grenfell John Lee , Herbst Konstantin , Sinnhuber Miriam , Taysum Ben , Wunderlich Fabian
Published: February 2023

The launch of the James Webb Space Telescope (JWST) in December 2021 opens up the possibility of studying the composition of exoplanetary atmospheres in habitable zones, such as TRAPPIST-1e, in the near future. With the help of numerical models of the exoplanetary atmospheres, the observations and the processes behind them can be better understood and interpreted (Herbst et al., 2022). We investigate the influence of stellar energetic particles (SEPs) and galactic cosmic rays (GCRs) on the atmospheric chemistry of exoplanets around a very active M-star using the ion chemistry model ExoTIC. In collaboration with the University of Kiel and DLR Berlin, we perform model experiments with different N2 or CO2 dominated atmospheres, depending on the initial CO2 partial pressure, as well as humid and dry conditions (Wunderlich et al., 2020), taking into account the ionization rates for such events. A further specification regarding the scenarios results from the distinction between dead and alive atmospheres, whose atmospheric composition is characterized by a lower or higher oxygen fraction in the initial conditions. Within ExoTIC we can calculate the impact of the ionization events on these atmospheres both as a single and as a series of events with different strengths. Preliminary results show a significant impact of SEP events on the chemical composition of the atmosphere, including biosignatures such as O3 . The strength and structure of these impacts depend on the composition of the starting atmosphere, in particular on the availability of oxygen as well as nitrogen and water vapour.
Planning of Urban Greenspace for Cooling Singapore: Modeling the Cooling Effects of Greenspace and Urban Morphology
Authors: Jia Siqi , Weng Qihao
Published: February 2023

The intensified accumulation of greenhouse gasses has led to rapid changes in global temperature trends and climate. In urban areas, this issue may also be exacerbated by the Urban Heat Island (UHI) effect. There is an extensive body of studies investigating the effectiveness of nature-based solutions in addressing these concerns. The majority of investigations have been conducted in evaluating the performance of urban greenspaces on cooling the environment since greenspaces can provide significant urban cooling via shade provision, evapotranspiration, and increased albedo. However, there remain some technical constraints for currently widely used methods for quantifying the cooling effect of greenspace. For example, although remote sensing techniques can provide spatially representative temperature observations over large areas from regional to global scales, satellite thermal sensors possess relatively low-spatial resolution. Therefore, this study proposes an effective temperature downscaling method to assess the cooling effect of urban greenspaces based on the high-resolution temperature data. A total of five sites among typical urban communities in a highly-density city/country - Singapore were selected as study areas. The temperature downscaling algorithm proposed in this research combines predictions of both the geographically weighted regression (GWR) and the neural network. Results show that the hybrid temperature downscaling method outperforms the conventional downscaling method on whole territories of study regions. The cooling effect of greenspace improves with both increments in the area and the intensity of greenspace (indicated by the green plot ratio; GnPR) with R2 of 0.12 and 0.24, respectively. The characteristics of the urban built environment can also affect the cooling effect of greenspace with the R2 between the cooling effect and the sky view factor (SVF) ranging from 0.10 to 0.22 among the sites. Based on the high-resolution cooling performance of greenspace, our research offered some interesting findings: (1) small greenspace with low canopy density (e.g., small patches of grassland) may deliver higher temperature than the temperature of surroundings, thus becoming local heat islands. (2) In sites characterized by relatively high SVF, greenspace is less effective in urban cooling with an increase of openness. This suggests the effect of wind in dense high-rise urban built environments. These findings may assist in better planning of urban greenspaces to increase their cooling effects among different urban communities. The model developed in this study can also be used in other studies to study the influences of potential driving factors on the cooling performance of urban greenspace or other types of nature-based solutions at the regional level.
The coupled uncertainty in negative emission technologies and transient climate response to cumulative CO2 emissions.
Authors: Di Natale Carla Maria , Tran Giang Thanh , Keller David P. , Schaber Theresa , Merikanto Joonas , Ekholm Tommi , Partanen Antti-Ilari
Published: February 2023

To meet the Paris Agreement targets, in addition to rapid emission reductions, carbon dioxide needs to be removed from the atmosphere with Negative Emission Technologies (NETs). On one hand, these solutions seem promising; on the other hand, they have significant and poorly estimated uncertainties and risks related to their potential to remove atmospheric carbon and wider impacts on the Earth system. One previously largely unexplored aspect of NETs is whether the uncertainty in NETs and e.g. transient climate response to cumulative CO2 emissions (TCRE) are coupled to any degree, e.g. could some NETs have lower carbon removal potential if TCRE is high. 

We estimate how TCRE and selected NETs’ carbon removal potential are dependent on climate system parameters using Perturbed Parameter Ensemble (PPE) with the University of Victoria Earth System Climate Model (UVic ESCM) and Gaussian Process (GP) emulator. Our aim is to explore and quantify any potential correlation between the carbon removal potential of single NETs and TCRE. The NETs considered are afforestation, reforestation, ocean alkalinization, ocean iron fertilization and direct air capture, which all except the last one depend on the perturbed parameters. 

The parameters of interest are chosen according to their expected impact on the climate and carbon uptake, constrained according to observations, and perturbed based on their prior probability distribution functions (PDFs). Then, to explore the parameter’s space, we use GP emulators to estimate model outputs as surrogate of actual ESM runs, which would be computationally too expensive. The emulators are created for the preindustrial spin-up, historical period, future control scenario and one for each NET scenario. They are trained through 300 simulations, considering 20 perturbed parameters. This analysis yields the correlation between the carbon removal potential of each NET and TCRE, and the contribution of each perturbed parameter to these two metrics. 

The preliminary results from the 300-member ensemble give a mean TCRE of 1.63 °C/1000 PgC, which is consistent with the best estimate of 1.65 °C/1000 PgC reported by the IPCC AR6 WGI (2021). The simulations with a high TCRE also tended to have a high ocean iron fertilization’s potential, meaning that some NETs are potentially more effective in removing atmospheric carbon dioxide if the temperature change per cumulative carbon dioxide emissions is high. Identifying such correlations between TCRE and NETs’ potential allows designing more robust mitigation strategies including portfolios of NETs that hedge against high TCRE. 
Drilling the Ivrea-Verbano zonE project: DT-1b borehole geophysics
Authors: Li Junjian , Greenwood Andrew , Caspari Eva , Pierdominici Simona , Kück Jochem , Baron Ludovic , Venier Marco ,   DIVE Drilling project Science team
Published: February 2023

The ICDP Drilling the Ivrea-Verbano zonE project (DIVE), aims at unravelling long-standing fundamental questions on the nature of the continental lower crust, its lithological correlation with geophysical anomalies and the characteristics of the underlying physical and chemical rock properties. Borehole geophysics provides an excellent opportunity and is the method of choice to explore the origin of geophysical anomalies, observed within the Ivrea-Verbano Zone, and their link to lithologies of the lower crust across several spatial scales. The first borehole of the DIVE project DT-1b in Ornavasso, Val’d Ossola (Italy), drilled into the Massone antiform, has been completed in December 2022 at a depth of 578.5 m. Geophysical borehole experiments comprising a suite of downhole logging and vertical seismic profiling (VSP) measurements have been conducted in two stages. A select set of first-look logs were collected to a depth of 315 m and a full suite at the end of drilling. The drilled rock types are metapelite, metapsammite, schist, gneiss, amphibolite, and, in places, migmatite and pegmatite. Several fractures are encountered within the drilled rock mass, exhibiting a NW-SE orientation and a variation of dip angles as identified by acoustic televiewer data. The acoustic televiewer data also show a couple of breakout zones, which may allow to constrain the current stress field orientation after carefully analyzing the impact of the topography. Preliminary results of the wireline logs suggest that they broadly correlate with the different rock types. Notably, the amphibolites as well as some of the more pelitic migmatites and gneiss exhibit locally high values of magnetic susceptibility of the order of 1000 10-6 SI. These values are confirmed by magnetic susceptibility measurements performed on drilled cores on-site with a self-built manual core scanner. Such high values have been reported in previous studies for amphibolites and mafic granulites in the Ivrea-Verbano zone and are most likely related to pyrrhotite and magnetite. Apart from the amphibolites, for most of the other rock types encountered, a weak correlation between magnetic susceptibility and the natural gamma radiation can be observed. The sonic P-wave velocities and preliminary P-wave velocity estimates of the VSP data are generally consistent. The average P-wave velocity estimate from the VSP is 5.3 km/s and slightly lower than the average estimate of 5.6 km/s obtained from the sonic logs. An integrated analysis of the complete set of the borehole geophysical data is currently undertaken to classify the rock mass with respect to their geophysical responses and to systematically delineate the underlying major factors of influence governing these responses.
Potential applications of the Benford’s Law for the investigation of hydrological time series alteration
Authors: Domeneghetti Alessio , Caroscio Letizia , Ceola Serena
Published: February 2023

The Benford’s Law, outlined in 1938, estimates the expected frequency of the significant first or first two digits of a time series of a generic variable based on a logarithmic pattern. Lower digits (i.e., 1, 2…) are expected to occur with frequencies higher than those associated to numbers with higher first digits (i.e., 8, 9). According to this law digit 1 typically occurs about 30% of the time, while 9 appears as significant first digit in less than 5% of the cases. The validity of Benford’s Law has been proven for a wide variety of data sets and in different contexts (e.g., public elections, false accounting detection, street addresses, stock and house prices, population numbers), among which few of hydrological relevance: lengths of rivers, river flow series, lake and wetlands extents. Nonconformity of hydrologic data sets to Benford’s Law could be a consequence of time series alteration and thus a signal of the presence of biases or errors, data modification, as well as of the fact that the sample is not fully representative of the variable or the series is affected by external drivers (e.g. anthropic alteration of the natural dynamics).In this work we referred to more than 1200 GRDC sites to test the Benford’s Law validity over stream flow series longer than 40 years, as well as on the longest stream flow series (more than 12 million of data). Streamflow records have been investigated in parallel to other hydrological relevant datasets that serve as proxy for quantifying the potential human impact (e.g., GRanD-Global Reservoir and Dam Database, FFRs-Free Flowing Rivers). Results of this study, together with those of previous investigations (Nigrini and Miller, 2007) advocate that large hydrological data set should conform the Benford’s Law. On the contrary, the nonconformity to it might highlight data integrity and authenticity issue, or reveal alterations of the natural variability due to human activities or other driving factors (perhaps climate change).
The influence of using ERA-5 instead of ERA-Interim on stratospheric chemistry and ozone in EMAC simulations
Authors: Kirner Ole , Laeng Alexandra , Jöckel Patrick
Published: February 2023

In 2019, the European Centre for Medium-Range Weather Forecasts (ECMWF) published the ERA-5 reanalysis dataset (Hersbach et al., 2020). These new reanalysis data set replaced ERA-Interim (Dee at al., 2011), which had been previously often used in nudged simulations.ERA-5 provides hourly estimates of a large number of atmospheric, land and oceanic climate variables. It uses a horizontal resolution of T639 (approx. 31km) and resolves the atmosphere using 137 levels from the surface up to a height of 1 Pa (approx. 80km). ERA-Interim only used T255 (approx. 79 km) with 60 levels from the surface up to 10 Pa (approx. 60 km) with a 6-hourly output.To investigate the impact of these two reanalyses on the results of chemistry-climate simulations with the ECHAM/MESSy Atmospheric Chemistry (EMAC) model system, we performed three nudged simulations from 1979 to present.EMAC is a numerical chemistry and climate simulation system that includes submodels describing tropospheric and middle-atmospheric processes and their interaction with oceans, land and human influences (Jöckel et al., 2010). We used EMAC (ECHAM5 version 5.3.02, MESSy version 2.55) with a horizontal resolution of T42 (corresponding to a quadratic Gaussian grid of 2.8° x 2.8°) and with 90 levels up to 0.01 hPa (approx. 80 km). The applied model setup includes a comprehensive chemistry scheme with gas-phase reactions and heterogeneous reactions on polar stratospheric clouds (PSCs). We used a similar setup as in the REF-D1 simulations for the IGAC/SPARC Chemistry-Climate Model Initiative (CCMI) using boundary conditions for greenhouse gases from CMIP-6 (Eyring et al., 2016) and for ozone depleting substances mainly from WMO (2008). Surface pressure, temperature, vorticity and divergence were nudged above the boundary layer and below 1 hPa (approx. 50 km) using a Newtonian relaxation technique.We performed three EMAC simulations all with the same model setup as described above, but used as reanalysis data set ERA-Interim in the first simulation (from 1979 to 201908), and ERA-5 in the second and third simulation (from 1979 to 2021). In the third simulation we used from 2000 to 2006 the ERA-5.1 data set instead of the ERA-5. ERA-5.1 is a rerun of ERA5 for the years 2000 to 2006 only, in which the cold bias in the lower stratosphere seen in ERA5 was improved.In our presentation, we will compare these three EMAC simulations regarding temperature, dynamic and chemistry with focus of the influence of the different reanalysis data sets to the distribution and development of stratospheric ozone.Additional we will present the comparisons of ozone fields of our three simulations with different satellite observations (in particular MIPAS and MLS) and access whether the use of ERA-5 leads to an improvement of the results of our EMAC simulations.
Analysis of Scale-dependent Spatial Correlations of Actual Evapotranspiration Measured by Lysimeters
Authors: Lu Xiao , Groh Jannis , Pütz Thomas , Vereecken Harry , Hendricks Franssen Harrie-Jan
Published: February 2023

Actual evapotranspiration (ETa) is difficult to measure and limited long-term information is available about ETa. With eddy covariance systems ETa can be measured at the field scale, but the method is associated with energy balance closure issues. For measuring ETa, weighing lysimeters are considered to be the most accurate and reliable method. However, weighing lysimeters have some disadvantages like elevated costs of installation and maintenance, and a small footprint (e.g., about 1 m2). A main question is therefore whether the precise ETa-measurements by lysimeters are representative for a larger area like a field, a meso-scale catchment, or even a larger region. Our hypothesis was that a lysimeter provides information about ETa that represents a larger area than its underlying measurement area. To this end, we examined here the daily ETa measurements from lysimeter at four study sites across Germany (separation distances 10 - 500 km) for the years 2015 to 2020. The Pearson correlations of the standardized anomalies (SA) of daily ETa between different lysimeters were calculated and compared with SA of daily ETa obtained from the corresponding eddy covariance tower. The correlations were further analyzed and related to spatial correlations of SA of environmental controls like precipitation, potential evapotranspiration (ET0), and soil moisture. We found that SA of daily ETa shows high spatial correlations (>0.5) for considerable separation distances between sites of up to 50km, with similar correlations for lysimeters and eddy covariance systems. ET0 is the dominant factor for the spatial correlation of ETa, as SA of ET0 shows stronger spatial correlations than SA of ETa.
A Google Earth Engine (GEE) system/tool for the monitoring of active volcanoes at a global scale
Authors: Marchese Francesco , Genzano Nicola , Pergola Nicola
Published: February 2023

The NHI (Normalized Hotspot Indices) system performs the automated monitoring of volcanic thermal anomalies at global scale under the Google Earth Engine (GEE) platform, by integrating information from Sentinel-2 MSI and Landsat 8/9 OLI/OLI-2 data. Thermal anomalies flagged by the NHI system may be then investigated through the tool. The latter enables the analysis of volcanic thermal features in terms of hot spot pixels, total SWIR (short wave infrared) radiance and total hotspot area, with low processing times. In this study, we present some recent results of the active volcanoes investigation performed using the tool, starting from the automated NHI detections. Results show that the NHI system/tool may provide a relevant contribution to the monitoring of thermal volcanic activity in both remote and well-monitored areas, thanks to the capacity in detecting and mapping hot targets with a low false positive rate.
Implementation and evaluation of Landscape-DNDC model for forestry management methods in a nutrient-rich peatland site in southern Finland.
Authors: Shahriyer Ahmed , Markkanen Tiina , Kajasilta Henri , Korkiakoski Mika , Rautakoski Helena , Gao Yao , Orttenvuouri Suvi , Fer Istem , Haas Edwin , Kraus David , Grote Ruediger , Aurela Mika , Lohila Annalea , Aalto Tuula
Published: February 2023

Draining peatlands for forestry and agriculture has been a common practice in Nordic countries in the last century. In drained peatland forests, trees act as carbon sink, while well-aerated peat soil is a source of carbon. Traditionally in even aged forestry all the trees are removed in clear-cut harvesting, whereas the continous cover forestry, with partial removal of a stand in selection cuttings, have been suggested to serve as climate wise option for peatlands. A process-based model ‘Landscape De-Nitrification De-Composition’ (LDNDC) was used to simulate fluxes of matter and energy of a drained nutrient-rich peatland forest ecosystem in southern Finland. LDNDC utilizes several sub-models for physiology, biogeochemistry, hydrology and microclimate and it simulates ecosystem water, energy and carbon balances including methane balance along with vegetation structure development. Multiple species can be simulated simultaneously as a mixed forest cohort, and contributions of the ground vegetation can be included. Different management methods of the forestry industry, e.g clear cutting or selection cutting have been simulated successfully. Local meterological data from 2010-2018 was used to drive the model and this data was cycled through several times to start the simulation run from 1969. The amount of carbon storage in the soil was set according to the measurements at nutrient-rich peatlands. Three different simulation runs were made for a clear-cut or a selection cutting taking place in 2016 and a reference forest with no cutting. Pine was simulated as a dominant tree species prior to the management actions along with spruce and birch as a secondary canopy and alpine meadows as ground vegetation. Eddy covariance and chamber measurements from both management and reference sites were used to evaluate model performance.  The model captured the net ecosystem exchange, gross primary production, terrestrial ecosystem respiration and methane fluxes well. The model also captured the changes in soil moisture and water-table level caused by the applied forest management methods. Leaf area index (LAI) of the combined vegetation cohort represented the measured LAI quite well along with the growth of the individual species. Successful implementation of the model resulted in extension of simulations until 2100 using different climate drivers to investigate effects of future management scenarios on various ecosystem balances. These model results can be utilized to provide recommendations for peatland forest management, which can ensure reduction in forestry related emissions and improve the possibilities for the peatland forest to act as a sink of carbon.