bluuebunny/crossref_metadata_2025 huggingface dataset:
Relative impact of irrigation techniques and climate change on hydroclimatic regimes in the Mediterranean region
Authors: Pool Sandra , Francés Félix , Garcia-Prats Alberto , Pulido-Velazquez Manuel , Sanichs-Ibor Carles , Schirmer Mario , Yang Hong , Jiménez-Martínez Joaquin
Published: March 2021

Irrigated agriculture is the major water consumer in the Mediterranean region. Improved irrigation techniques have been widely promoted to reduce water withdrawals and increase resilience to climate change impacts. In this study, we assess the impact of the ongoing transition from flood to drip irrigation on future hydroclimatic regimes in the agricultural areas of Valencia (Spain). The impact assessment is conducted for a control period (1971-2000), a near-term future (2020-2049) and a mid-term future (2045-2074) using a chain of models that includes five GCM-RCM combinations, two emission scenarios (RCP 4.5 and RCP 8.5), two irrigation scenarios (flood and drip irrigation), and twelve parameterizations of the hydrological model Tetis. Results of this modelling chain suggest considerable uncertainties regarding the magnitude and sign of future hydroclimatic changes. Yet, climate change could lead to a statistically significant decrease in future groundwater recharge of up -6.6% in flood irrigation and -9.3% in drip irrigation. Projected changes in actual evapotranspiration are as well statistically significant, but in the order of +1% in flood irrigation and -2.1% in drip irrigation under the assumption of business as usual irrigation schedules. The projected changes and the related uncertainties will pose a challenging context for future water management. However, our findings further indicate that the effect of the choice of irrigation technique may have a greater impact on hydroclimate than climate change alone. Explicitly considering irrigation techniques in climate change impact assessment might therefore be a way towards better informed decision-making.

This study has been supported by the IRRIWAM research project funded by the Coop Research Program of the ETH Zurich World Food System Center and the ETH Zurich Foundation, and by the ADAPTAMED (RTI2018-101483-B-I00) and TETISCHANGE (RTI2018-093717-B-I00) research projects funded by the Ministerio de Economia y Competitividad (MINECO) of Spain including EU FEDER funds.
Exploring the potential of soil moisture reanalysis data for improving the identification of regional landslide triggering thresholds
Authors: Palazzolo Nunziarita , Peres David J. , Creaco Enrico , Cancelliere Antonino
Published: March 2021

Landslide triggering thresholds provide the rainfall conditions that are likely to trigger landslides, therefore their derivation is key for prediction purposes. Different variables can be considered for the identification of thresholds, which commonly are in the form of a power-law relationship linking rainfall event duration and intensity or cumulated event rainfall. The assessment of such rainfall thresholds generally neglects initial soil moisture conditions at each rainfall event, which are indeed a predisposing factor that can be crucial for the proper definition of the triggering scenario. Thus, more studies are needed to understand whether and the extent to which the integration of the initial soil moisture conditions with rainfall thresholds could improve the conventional precipitation-based approach. Although soil moisture data availability has hindered such type of studies, yet now this information is increasingly becoming available at the large scale, for instance as an output of meteorological reanalysis initiatives. In particular, in this study, we focus on the use of the ERA5-Land reanalysis soil moisture dataset. Climate reanalysis combines past observations with models in order to generate consistent time series and the ERA5-Land data actually provides the volume of water in soil layer at different depths and at global scale. Era5-Land project is, indeed, a global dataset at 9 km horizontal resolution in which atmospheric data are at an hourly scale from 1981 to present. Volumetric soil water data are available at four depths ranging from the surface level to 289 cm, namely 0-7 cm, 7-28 cm, 28-100 cm, and 100-289 cm. After collecting the rainfall and soil moisture data at the desired spatio-temporal resolution, together with the target data discriminating landslide and no-landslide events, we develop automatic triggering/non-triggering classifiers and test their performances via confusion matrix statistics. In particular, we compare the performances associated with the following set of precursors: a) event rainfall duration and depth (traditional approach), b) initial soil moisture at several soil depths, and c) event rainfall duration and depth and initial soil moisture at different depths. The approach is applied to the Oltrepò Pavese region (northern Italy), for which the historical observed landslides have been provided by the IFFI project (Italian landslides inventory). Results show that soil moisture may allow an improvement in the performances of the classifier, but that the quality of the landslide inventory is crucial.
Improving Sub-Seasonal Hydrological Forecasts in Switzerland: An Exploratory Study of Post-Processing Techniques by Using Machine Learning and Weather Regime Diagnostics
Authors: Chang Yuan-Yuan (Annie) , Bogner Konrad , Zappa Massimiliano , Domeisen Daniela I.V. , Grams Christian M.
Published: March 2021

Across the globe, there has been an increasing interest in improving the predictability of weekly to monthly (sub-seasonal) hydro-meteorological forecasts as they play a valuable role in medium- to long-term planning in many sectors such as agriculture, navigation, hydro-power production, and hazard warnings. A Precipitation-Runoff-Evapotranspiration HRU model (PREVAH) has been previously set up with raw metrological forcing of 51 ensemble members and 32 days lead time taken from the operational European Centre for Medium-Range Weather Forecasts (ECMWF) extended-range forecast. The PREVAH model is used to generate hydrological forecasts for the study area, which consists of 300 catchments covering approximately the entire area of Switzerland. The primary goal of this study is to improve the quality of the categorical forecast of weekly mean total discharge in a catchment laying in the lower, normal, or upper tercile of the climatological distribution at a monthly horizon. Therefore, we explore the approach to post-process PREVAH outputs using machine learning algorithm Gaussian process. Weather regime (WR) data, based on 500 hPa geopotential height in the Atlantic-European region are used as an added feature to further enhance the post-processing performance.

By comparing the overall accuracy and the ranked probability skill score of the post-processed forecasts with the ones of raw forecasts we show that the proposed post-processing techniques are able to improve the forecast skill. The degree of improvement varies by catchment, lead time and variable. The benefit of the added WR data is not consistent across the study area but most promising in high altitude catchments with steep slopes. Among the seven types of WRs, the majority of the corrections are observed when either a European blocking or a Scandinavian blocking is forecasted as the dominant weather regime. By applying a “best practice” to each individual catchment, that is the processing technique with the highest accuracy among the different proposed techniques, a median accuracy of 0.65 (improved from a value of 0.53 with no processing technique) can be achieved at 4-week lead time. Due to the small data size, the conclusions should be considered preliminary, but this study highlights the potential of improving the skill of sub-seasonal hydro-meteorological forecasts utilizing weather regime data and machine learning in a real-time deployable setup.
Statistics of 20 years of heavy precipitation events in Germany from radar data
Authors: Lengfeld Katharina , Walawender Ewelina , Winterrath Tanja , Weigl Elmar , Becker Andreas
Published: March 2021

Extreme precipitation events are expected to occur more frequently in a warming climate. Understanding their structure and predicting the exact time and location of precipitation events still remains a challenge because of the high temporal and spatial variability of rainfall. Nationwide weather radar networks are a common tool for investigating precipitation events and their spatial and temporal structure. The German Weather Service (DWD) provides a nationwide climatological radar data set from 2001 to 2020. A reprocessing procedure has been applied to reflectivity measurements in order to obtain precipitation estimates as homogeneous as possible. With an object-oriented analysis, all precipitation events for 11 different durations from 1 to 72 hours exceeding DWD’s official warning level for heavy precipitation have been detected and statistically analysed.

We will present a comprehensive analysis of all heavy precipitation events that occurred in Germany between 2001 and 2020. We examined their size, duration, location, spatial structure and distribution as well as regional and climatological differences and demonstrate how this information is collected in an online tool for easy access. An assessment of how well these heavy precipitation events were captured by DWD’s network of precipitation stations will be given. Finally, we will present the possibility to use the event detection procedure as an operational tool for assessing and classifying heavy precipitation events and their potential impact in near real-time.
Area and volume quantification of arctic thaw slumps using time-series of digital elevation models generated from radar interferometry
Authors: Bernhard Philipp , Zwieback Simon , Hajnsek Irena
Published: March 2021

Vast areas of the Arctic host ice-rich permafrost, which is becoming increasingly vulnerable to terrain-altering thermokarst in a warming climate. Among the most rapid and dramatic changes are retrogressive thaw slumps. These slumps evolve by a retreat of the slump headwall during the summer months, making their change visible by comparing digital elevation models over time. In this study we use digital elevation models generated from single-pass radar TanDEM-X observations to derive volume and area change rates for retrogressive thaw slumps. At least three observations in the timespan from 2011 to 2017 are available with a spatial resolution of about 12 meter and a height sensitivity of about 0.5-2 meter. Our study regions include regions in Northern Canada (Peel Plateau/Richardson Mountains, Mackenzie River Delta Uplands, Ellesmere Island), Alaska (Noatak Valley) and Siberia (Yamal, Gydan, Taymyr, Chukotka) covering an area of 220.000 km2 with a total number of 1853 thaw slumps.

In this presentation we will focus on the area and volume change rate probability density functions of the mapped thaw slumps in these study areas. For landslides in temperate climate zones the area and volume change probability density function typically follow a distribution that can be characterized by three quantities: A rollover point defined as the peak in the distribution, a cutoff-point indicating the transition to a power law scaling for large landslides and the exponential beta coefficient of this power law. Here we will show that thaw slumps across the arctic follow indeed such a distribution and that the obtained values for the rollover, cutoff and beta coefficient can be used to distinguish between regions. Furthermore we will elaborate on possible reason why arctic thaw slumps can be described by such probability density functions as well as analyzing the differences between regions. This characterization can be useful to further improve our understanding of thaw slump initiation, the investigation of the drivers of their evolution as well as for modeling future thaw slump activity.
Atmospheric production and transport of 7Be activity by cosmic rays: Modelling with the chemistry-climate model SOCOLv3.0 and comparison with direct measurements
Authors: Golubenko Kseniia , Rozanov Eugene , Kovaltsov Genady , Leppänen Ari-Pekka , Usoskin Ilya
Published: March 2021

We present the first results of modelling of the short-living cosmogenic isotope 7Be production, deposition, and transport using the chemistry-climate model SOCOLv3.0 aimed to study solar-terrestrial interactions and climate changes. We implemented an interactive deposition scheme,  based on gas tracers with and without nudging to the known meteorological fields. Production of 7Be was modelled using the 3D time-dependent Cosmic Ray induced Atmospheric Cascade (CRAC) model. The simulations were compared with the real concentrations (activity) and depositions measurements of 7Be in the air and water at Finnish stations. We have successfully reproduced and estimated the variability of the cosmogenic isotope 7Be produced by the galactic cosmic rays (GCR) on time scales longer than about a month, for the period of 2002–2008. The agreement between the modelled and measured data is very good (within 12%) providing a solid validation for the ability of the SOCOL CCM to reliably model production, transport, and deposition of cosmogenic isotopes, which is needed for precise studies of cosmic-ray variability in the past. 
Comparing 3D vs 2D approach in vorticity estimates
Authors: Montemagni Chiara , Zanchetta Stefano , Iaccarino Salvatore , Montomoli Chiara , Carosi Rodolfo , Fusi Nicoletta
Published: March 2021

Kinematic analysis of flow is becoming a well-established methodology, increasingly applied for its capability to contribute to the solution of complex topics in structural geology and tectonics, such as shear zones deforming by general shear.

Vorticity evaluations based on stable porphyroclasts method have been used for many years to deduce large-scale tectonics of shear zones with different kinematics (Fossen & Cavalcante, 2017). However, limitations occur because a complex three dimensional problem, the motion of rigid clasts in a flowing matrix, is reduced to its two-dimensional analysis on the XZ plane of the finite strain ellipsoid (Iacopini et al., 2011; Mancktelow, 2013). Therefore vorticity estimates are limited by the extrapolation to three dimensions of two-dimensional data.

We propose a totally new 3D approach based on the use of X-ray micro-computed tomography (X-ray micro-CT) that reflects the real 3D geometry and orientation of the porphyroclasts population. X-ray micro-CT allows to face the loss of dimensionality information imaging the rock sample in three dimensions and produces stacks of 2D grey-scale value images, called “slices”, that combined in 3D allow observing the internal structure of the scanned sample.

We tested this approach chiefly on mylonitic orthogneiss from an intensively studied crustal scale shear zone: the Main Central Thrust zone (MCTz) of the Himalaya orogenic belt. Mylonites samples from other regional-scale shear zones in the Alps have been also used for comparison.

The first and foremost consideration is that the use of micro-CT certainly increases the number of investigated clasts because hand samples are scanned: all clasts are evaluated. Micro-CT minimizes the problems due to the isolation factor, as it becomes possible to only select the clasts that do not interact with each other. Moreover, observation in three dimensions allows a more realistic evaluation of the aspect ratios and radii of clasts, avoiding erroneous measurements that generate systematic errors in the vorticity evaluation.

We would like to stress that using the microCT we are able to evaluate all the clasts in the sample, avoiding those which do not meet the prerequisites of the method, otherwise not possible using classical 2D thin section based analysis.

 

Fossen H. & Cavalcante G.C.G., 2017. Earth-Sci. Rev., 171, 434–455.

Iacopini D. et alii, 2011. GSL Spec. Publ., 360, 301–318.

Mancktelow N.S., 2013. J. Struct. Geol., 46, 235-254.

Montemagni C. et alii, 2020. Terra Nova, 32, 215-224.
Towards Developing Community Guidelines for Sharing and Reusing Quality Information of Earth Science Datasets
Authors: Lacagnina Carlo , Peng Ge , Downs Robert R. , Ramapriyan Hampapuram , Ivanova Ivana , Moroni David F. , Wei Yaxing , Bastin Lucy , Ritchey Nancy A. , Larnicol Gilles , Wyborn Lesley A. , Shie Chung-Lin , Habermann Ted , Ganske Anette , Champion Sarah M. , Wu Mingfang , Bastrakova Irina , Jones Dave , Berg-Cross Gary
Published: March 2021

The knowledge of data quality and the quality of the associated information, including metadata, is critical for data use and reuse. Assessment of data and metadata quality is key for ensuring credible available information, establishing a foundation of trust between the data provider and various downstream users, and demonstrating compliance with requirements established by funders and federal policies.

Data quality information should be consistently curated, traceable, and adequately documented to provide sufficient evidence to guide users to address their specific needs. The quality information is especially important for data used to support decisions and policies, and for enabling data to be truly findable, accessible, interoperable, and reusable (FAIR).

Clear documentation of the quality assessment protocols used can promote the reuse of quality assurance practices and thus support the generation of more easily-comparable datasets and quality metrics. To enable interoperability across systems and tools, the data quality information should be machine-actionable. Guidance on the curation of dataset quality information can help to improve the practices of various stakeholders who contribute to the collection, curation, and dissemination of data.

This presentation outlines a global community effort to develop international guidelines to curate data quality information that is consistent with the FAIR principles throughout the entire data life cycle and inheritable by any derivative product.
From rivers to retailers: using cross-sector stakeholder engagement to broaden dissemination and guide future research
Authors: Stanton Thomas , Kay Paul , Gomes Rachel , Johnson Matthew , Weeks Jason
Published: March 2021

Concern for the fate and impacts of plastic waste has motivated cross-sector engagement with the environment and society’s impact on it. Though efforts to minimise plastic pollution should not be discouraged, it is important that such efforts do not exacerbate the environmental impacts associated with plastic alternatives; acknowledge that plastic per se is not the root of the plastic pollution problem; and recognise that environmentally conscious consumption is a privilege not currently afforded to all. Cross-sector communication and cooperation can maximise the impact of plastic pollution research and are vital tools in ensuring research can inform positive change. Here we report on the use of stakeholder engagement spanning UK industry, government, not-for-profit organisations and academia to share knowledge, motivations and priorities, in order to broaden research impact beyond academia.

Informed by our own work, microplastic researchers at the University of Nottingham hosted a cross-sector workshop to recognise evidence requirements, focus key questions, highlight misunderstandings and ultimately identify knowledge gaps across multiple sectors. This engagement identified key areas for improvement from the scientific community in order to better inform and engage decision makers. These included: a need for greater clarity from the scientific community as to the extent of the plastic pollution problem; communication of the implications of methodological inconsistencies in the science that informs industry; and the importance of placing the impacts of plastic pollution within the context of broader environmental quality for non-scientific stakeholders.

This workshop and engagement led to outputs that included: the writing of a policy brief; the writing of an opinion article on the topic of plastic pollution with authors from not-for profits, the wastewater industry and government organisations; and the public dissemination of these activities through press releases, articles for The Conversation, and their reproductions in UK news media. These outputs are designed to guide and inform individuals, industry, decision makers, and future research.

Concern for the problems posed by plastic pollution presents a generational opportunity for science to inform industries, governments and consumers, and enthuse their environmental action beyond plastic pollution. Our work highlights the value of considering, and where feasible engaging with, these stakeholders with environmental research from conception to dissemination.
Detecting regime transitions in the stable boundary layer
Authors: Vercauteren Nikki , Kaiser Amandine , Boyko Vyacheslav , Faranda Davide , Krumscheid Sebastian
Published: March 2021

Predictability of the atmospheric boundary layer is impaired by possible rapid transitions between fully turbulent states and quiescent, quasi-laminar states. Such rapid transitions are observed in Polar regions or at night when the atmospheric boundary layer is stably stratified, and they have important consequences in the strength of mixing with the higher levels of the atmosphere. 

In some cases, perturbations of the flow can play an important role in triggering transitions. Using different randomised models of the stable boundary layer, we will investigate the role of natural fluctuations of atmospheric processes to trigger regime transitions. 

We then apply a combination of methods from dynamical systems, statistical modelling and information theory to study and detect those regime transitions. A statistical-dynamical indicator is developed as an early-warning signal of regime transitions that can be applied to highly non-stationary field data. 
Analysing crystal distortions to deduce dislocation slip systems
Authors: Wheeler John , Piazolo Sandra , Prior David , Tielke Jake , Trimby Pat
Published: March 2021

In many parts of the Earth rocks deform by dislocation creep. There is therefore a need to understand which slip systems operated in nature and in experimental products. Knowing the conditions of experiments may then allow natural conditions and strain rates to be characterised. Dislocation creep typically gives lattice preferred orientations (LPOs), since activity on particular slip systems leads to lattice rotations and alignment. For decades LPOs, measured first optically and since the 1990s by EBSD, have been used to infer slip systems. This is a valuable technique but the link between slip sytem activity and LPO is complicated, especially if recrystallisation and/or grain boundary sliding have been involved.

Here we present a more direct method to deduce “geometrically necessary” dislocations (GNDs) from the distortions within crystals. Distortions may be optically visible (e.g. undulose extinction in quartz) but EBSD has revealed how common distortions are, and allowed them to be quantified. The method does not give the complete picture of GNDs but allows hypotheses to be tested about possible slip systems. We illustrate this “Weighted Burgers Vector” method with a number of examples. In olivine the method distinguishes slip parallel to a and c, and in plastically deformed plagioclase it reveals a variety of slip systems which would be difficuilt to deduce from LPOs alone. GNDs may not necessarily reflect the full slip system activity, since many dislocations will have passed through crystals and merged with grain boundaries leaving no signature. Neverthless the method highlights what dislocations are present “stranded” in the microstructure. In many case these will have been produced by deformation although the method can also characterise growth defects.

Wheeler et al. 2009. The weighted Burgers vector: a new quantity for constraining dislocation densities and types using electron backscatter diffraction on 2D sections through crystalline materials. DOI: 10.1111/j.1365-2818.2009.03136.x
Modelling the salinity response to fresh water flow and variable tidal amplitude in an idealized river delta 
Authors: Matsoukis Constantinos , O. Amoudry Laurent , Bricheno Lucy , Leonardi Nicoletta
Published: March 2021

High salinity values in deltaic regions can be detrimental for agriculture, aquaculture and human consumption. Salinity levels in river deltas could significantly increase due to sea level rise and infrastructure works such as river diversions or dam constructions. River flow and tides have a large influence on salinity concentrations and it is thus important to understand their combined role. In this paper, a 3D model is built for an idealized delta. A series of simulations is carried out to investigate salinity fields developed under the combined action of tidal amplitude and fresh water flow. Simulations are classified based on the ratio between fresh water and tidal range. Both tide influenced and river dominated cases were considered. Results emphasize the importance of tidally driven mixing which can establish fresher conditions in the delta for certain amplitudes. Tidal amplitude increase enhances the flow in the delta and enlarges the fresh water layer thickness and length. On the other hand, the maximum tidal ranges can limit significantly the fresh water volume. The spatiotemporal salinity distribution is described in terms of delta topology and network geometry. Salinity and river discharge were found to be negatively and exponentially correlated by an equation that resembles solutions of the 1D advection-diffusion equation. Large bathymetric differences between delta areas were identified to play a key role on the salinity patterns as they can modify the nature of the extracted relationships and correlations.
Groundwater Recharge Indicators at the European scale
Authors: Lanini Sandra , Caballero Yvan , Le Cointe Pierre , Pinson Stéphanie , Desprats Jean-François
Published: March 2021

One of the goals of the ERA4CS INDECIS project (http://www.indecis.eu/) is to use available climate datasets at the European scale to derive user-oriented indicators. In this framework, we adapted a methodology to compute the present and future groundwater recharge by precipitation at the European scale. This indicator of groundwater availability aims at supporting water resource management.

The scientific approach partly relies on two indexes related to precipitation infiltration at the watershed scale. The first one is the BaseFlow Index (BFI) which is considered as a fair approximation of the average infiltration coefficient for hydrogeological basins. The second one is the Network Development and Persistence Index (IDPR), a cartographic index calculated from the differences between the real river and the theoretical thalwegs networks. The IDPR provides a qualitative indication of infiltration versus runoff, and is now available at the European scale with a 50 m resolution. We computed the mean interannual BFI over the 1981 – 2010 period for more than 350 gauged and not influenced watersheds distributed over France, with various geological contexts and climates. These BFI values proved to be linearly correlated to the spatial average of the IDPR over these watersheds. The relationship between the two datasets established on these gauged basins was then applied to convert the European IDPR map into an effective precipitation infiltration ratio (EPIR) map.

The modelling process finally consisted in computing the effective precipitation at a daily time step on each cell of a mesh covering the European area. Three different water budget models were applied. The only parameter of these models is the soil water capacity provided by European Soil Data Centre. For the present period, the models were fed with the E-OBS datasets available on a 0.25 degree grid. Resulting time series were time-averaged and multiplied by the spatialized EPIR to provide a European map of annual potential recharge by precipitation infiltration. For the future periods, the same methodology can be applied. Ensemble simulations are in progress using EURO-CORDEX climate projections as input of the hydrological models.
Megathrust shear force limits mountain height at convergent plate margins
Authors: Dielforder Armin
Published: March 2021

The shear force along convergent plate boundary faults, called megathrusts, determines the height of mountain ranges that can be mechanically sustained. However, whether the true height of mountain ranges corresponds to this tectonically supported elevation is debated. In particular, climate-dependent erosional processes are often assumed to exert a first-order control on mountain height, although this assumption has remained difficult to validate. To address this issue, I first constrained the shear force along active megathrusts from their rheological properties and then determined the tectonically supported elevation using a force balance model. This analysis revealed that the height of mountain ranges around the globe matches the tectonically supported elevation, irrespective of climatic conditions and the rate of erosion. This finding indicates that the height of mountain ranges is effectively limited by the megathrust shear force and implies that global differences in mountain height are at first-order tectonically controlled. Thus, temporal variations in mountain height should reflect long-term changes in the force balance rather than changes in climate.
Process taxonomies and copan:CORE modelling framework for studying human-Earth system interaction dynamics in the Anthropocene
Authors: Donges Jonathan F. , Heitzig Jobst , Lucht Wolfgang , Barfuss Wolfram , Cornell Sarah E. , Kassel Johannes , Kittel Tim , Kolb Jakob J. , Kolster Till , Lade Steven J. , Müller-Hansen Finn , Otto Ilona M. , Schlüter Maja , Wiedermann Marc , Zimmerer Kilian B.
Published: March 2021

Analysis of Earth system dynamics in the Anthropocene requires explicitly taking into account the increasing magnitude of processes operating in human societies, their cultures, economies and technosphere and their growing feedback entanglement with those in the physical, chemical and biological systems of the planet. However, current state-of-the-art Earth system models do not represent dynamic human societies and their feedback interactions with the biogeophysical Earth system and macroeconomic integrated assessment models typically do so only with limited scope. This paper (i) proposes design principles for constructing world–Earth models (WEMs) for Earth system analysis of the Anthropocene, i.e., models of social (world)–ecological (Earth) coevolution on up to planetary scales, and (ii) presents the copan:CORE open simulation modeling framework for developing, composing and analyzing such WEMs based on the proposed principles. The framework provides a modular structure to flexibly construct and study WEMs. These can contain biophysical (e.g., carbon cycle dynamics), socio-metabolic or economic (e.g., economic growth or energy system changes), and sociocultural processes (e.g., voting on climate policies or changing social norms) and their feedback interactions, and they are based on elementary entity types, e.g., grid cells and social systems. Thereby, copan:CORE enables the epistemic flexibility needed for contributions towards Earth system analysis of the Anthropocene given the large diversity of competing theories and methodologies used for describing socio-metabolic or economic and sociocultural processes in the Earth system by various fields and schools of thought. To illustrate the capabilities of the framework, we present an exemplary and highly stylized WEM implemented in copan:CORE that illustrates how endogenizing sociocultural processes and feedbacks such as voting on climate policies based on socially learned environmental awareness could fundamentally change macroscopic model outcomes.

References

Donges, J.F. et al.: Taxonomies for structuring models for World-Earth system analysis of the Anthropocene: subsystems, their interactions and social-ecological feedback loops, Earth Syst. Dynam. Disc., in review (2021), DOI: 10.5194/esd-2018-27.

Donges, J. F. and Heitzig,et al..: Earth system modeling with endogenous and dynamic human societies: the copan:CORE open World–Earth modeling framework, Earth Syst. Dynam., 11, 395–413, 2020.
Modelling Thousands of Fractures Using Analytic Elements
Authors: Toller Erik , Strack Otto
Published: March 2021

Understanding and modelling hydraulic fractures and fracture networks have a fundamental role in mapping the mechanical behaviour of rocks. A problem arises in the discontinuous behaviour of the fractures and how to accurately and efficiently model this. We present a novel approach for modelling many cracks randomly using analytic elements placed under plane strain conditions in an elastic medium. The analytic elements allow us to model the assembly computationally efficiently and up to machine precision. The crack element is the first step in the development of a model suitable for investigating the effect of fissures on tunnels in rock. The model can be used to validate numerical models and more.The solution for a single hydraulic pressurized crack in an infinite domain in plane strain was initially developed by Griffith (1921). We demonstrate that it is possible, by using series expansions in terms of complex variables, based on the Muskhelisvili-Kolosov functions, to generalize this solution to the case of an assembly of non-intersecting pressurized cracks. The solution consists of infinite series for each element Strack & Toller (2020). The expressions for the displacements and stress tensor components approach the exact solution, as the number of terms in the series approaches infinity.We present the case where two cracks approach each other orthogonally to less than 1/2000th of the cracks length. We show the effect of increasing the number of terms in the expansion and how this influences the precision, demonstrating that the result approaches the exact solution. We also present a case with 10,000 cracks; the coefficients are determined using an iterative solver. By using analytic elements, we can both present the corresponding stress and deformations field for the global scale and for small scales in the close proximity of individual cracks.ReferencesGriffith, A. A. (1921). The phenomena of rupture and ﬂow in solids. Philosophical Transactions of the Royal Society of London. Series A, Containing Papers of a Mathematical or Physical Character, 221(582-593):163–198.Strack, O. D. L. and Toller, E. A. L. (2020). An analytic element model for highly fractured elastic media, manuscript submitted for publication in International Journal for Numerical and Analytical Methods in Geomechanics.
Carbon emissions from fires in permafrost peatlands
Authors: Veraverbeke Sander , Delcourt Clement , Granath Gustaf , Kukavskaya Elena , Mack Michelle , Strengbom Joachim , Walker Xanthe , Hessilt Thomas , Rogers Brendan , Scholten Rebecca
Published: March 2021

Increases in arctic and boreal fires can switch these biomes from a long-term carbon (C) sink to a source through direct fire emissions and longer-term emissions from soil respiration. Landscapes of intermediate drainage tend to experience the highest C combustion, dominated by soil C emissions, because of relatively thick and periodically dry organic soils. These landscapes may also induce a climate warming feedback through combustion and post-fire respiration of legacy C – soil C that had escaped burning in the previous fire – including from permafrost thaw and degradation. Data shortages from fires in tundra ecosystems and Eurasian boreal forests limit our understanding of C emissions from arctic-boreal fires. Interactions between fire, topography, vegetation, soil and permafrost need to be considered when estimating climate feedbacks of arctic-boreal fires.
WesCon 2023: Wessex UK Summertime Convection Field Campaign
Authors: Barrett Paul , Abel Steven , Lean Humphrey , Price Jeremy , Stein Thorwald , Stirling Alison , Darlington Timothy
Published: March 2021

Faithfull physical representation of summertime convection over the United Kingdom, and beyond, remains elusive in convection permitting (CP) numerical weather prediction (NWP) models.  Biases include the incorrect representation of the size and spatial distribution characteristics of convective elements, timing errors in the diurnal cycle of convection and under-representation of high-intensity precipitation events. A key requirement for model improvement is 3D observations of convective clouds, updrafts and turbulence along with the pre-convective environment.

Increased computational power and novel parameterisation schemes (e.g. CoMORPH: scale-aware convection scheme, CASIM: Cloud AeroSols Interactive Microphysics) are on the cusp of facilitating significant advances to the representation of convective cloud systems, both at high resolution cloud resolving scales from O(100m) to O(1km) and for CP ensemble prediction systems. Observational constraints are now required to validate and develop this suite of numerical modelling and the WesCon campaign has been designed for this purpose.

Met Office and University of Reading are planning an observational field campaign from June through to August 2023 to investigate summertime convection. Focussing on the Wessex region encompassing South West and South Central England we will benefit from the remote sensing capability of  the Chilbolton Observatory to observe clouds and precipitation (including a new X-band radar) and the research radar (C-band) at Met Office Wardon Hill (Dorset) to observe precipitation structures.

Up to 80 research flight hours with the FAAM BAe146 research aircraft (Facility for Airborne Atmospheric Measurement) will probe the thermal, dynamical, updraughts and microphysical structures of the planetary boundary layer and lower free-troposphere on horizontal length-scales from the turbulence scale O(1 m) to the mesoscale (10’s kms). Ground based measurements will be deployed across the region making observations of surface exchange, turbulence and boundary layer properties. Radiosondes and dropsondes along with aircraft profiles will probe the atmosphere in the vertical.

Airborne measurements will place particular emphasis on the pre-convective environment, convective inhibition (CIN) and the early stages of the development of convective systems.  The full lifecycle of convective systems will be observed from the vantage point of remote sensing observations.

Here we present the aims and measurement strategy of the WesCon campaign and solicit interest and involvement from other modelling or observations groups within the community who may wish to join us to collaborate.
Steep-slope cultivated landscapes: towards climate-resilient water resources management
Authors: Wang Wendi , Pijl Anton , Tarolli Paolo
Published: March 2021

One of the most important tasks for humans in the 21st century is to ensure food security in the face of water scarcity. Steep-slope cultivated landscapes are widely distributed and feed more than 10% people in the world. They play an important role in Sustainable Development Goals (SDG) set in the United Nations Sustainable Development Summit which aimed to thoroughly solve the food problems in a sustainable way. In addition, more than 49 steep-slope cultivated landscapes are recognised and protected by UNESCO and FAO for their cultural and agronomic importance. It is necessary to find appropriate solutions towards climate-resilient water resources management and save more water for other ecosystems or human activities.

Climate change-induced drought and high intensity rainstorms are global challenges for water resources management in agricultural landscapes. Growing aridity and extreme rainfall are particularly exacerbating the problem of water scarcity in steep slope cultivated landscapes. Though a number of studies have shown the potential impact of climate change on agricultural systems, little is known about role of water resource management (water storages, water harvest, drainage systems, etc.) in the mitigation of these climate impacts to ensure sustainable farming in steep slope agricultural landscapes. The aim of our work is to analyse the threats and challenges of steep-slope agriculture due to climate change and provide examples of resilient water management and agricultural practices in these landscapes. In detail, the aims are to better understand and compare how shifting climatic zones particularly affect steep cultivated landscapes and to find a feasible way for water storage to sustain ecosystem service and agricultural cultivation on hillslope in long periods of drought. GIS-based techniques were employed to determine the global distribution of steep agricultural landscapes, and to quantify the fraction of these that are facing future aridity. Finally, key examples of best practices in sustainable water resource management around the world are discussed, providing a guideline for improving the resilience of steep cultivation systems in future climatic conditions.
EDR signatures observed by MMS : a statistical study of dayside events found with machine learning
Authors: Lenouvel Quentin , Génot Vincent , Garnier Philippe , Lavraud Benoit , Toledo Sergio
Published: March 2021

The understanding of magnetic reconnection's physical processes has considerably been improved thanks to the data of the Magnetopsheric Multiscale mission (MMS). However, a lot of work still has to be done to better characterize the core of the reconnection process : the electron diffusion region (EDR). We previously developed a machine learning algorithm to automatically detect EDR candidates, in order to increase the available list of events identified in the literature. However, identifying the parameters that are the most relevant to describe EDRs is complex, all the more that some of the small scale plasma/fields parameters show limitations in some configurations such as for low particle densities or large guide fields cases. In this study, we perform a statistical study of previously reported dayside EDRs as well as newly reported EDR candidates found using machine learning methods. We also show different single and multi-spacecraft parameters that can be used to better identify dayside EDRs in time series from MMS data recorded at the magnetopause. And finally we show an analysis of the link between the guide field and the strength of the energy conversion around each EDR.
Tree stem greenhouse gas emissions from forested closed landfill sites
Authors: Fraser-McDonald Alice , Boardman Carl , Gladding Toni , Burnley Stephen , Gauci Vincent
Published: March 2021

Tree planting has the potential to increase carbon sequestration and is used as a common management strategy on former landfill sites to improve their visual appeal and manage issues such as leachates from decomposing organic matter. Tree stems mediate methane (CH4) emissions to the atmosphere from anaerobic soils, bypassing bacterial populations that would otherwise break down CH4 before it is released to the atmosphere. This process has been observed in wetland forests but has yet to be measured in a landfill context. We examined whether trees emitted more CH4 and carbon dioxide (CO2) on a closed UK landfill site relative to a more natural, comparable control site to determine the importance of this natural phenomenon in a managed environment. CH4 and CO2 fluxes from tree stem and soil surfaces were measured using flux chambers and an off-axis integrated cavity output spectroscopy analyser. Temporal and seasonal variations in greenhouse gas emissions from landfill tree stems were also investigated, as well as the impact of different landfill management techniques including site closure methods and tree species planted. Analyses showed that tree stem emissions from landfill were larger than from trees in the non-landfill control site. However, there was high variability in the greenhouse gas fluxes from trees on the landfill. Findings from this investigation suggest that conditions associated with landfill construction may increase CH4 emissions from trees planted on their surface after closure of the site. Trees planted on former landfill sites may therefore result in additional CH4 emissions to the atmosphere.
Natural Hazards: from Plinius’ time to the Anthropocene
Authors: Di Baldassarre Giuliano
Published: March 2021

Plinius (23-79 AD) is known worldwide as the author of the encyclopedic Naturalis Historia. He died in Stabiae while trying to rescue his family from the eruption of Mount Vesuvius, one of the deadliest volcanic eruptions in European history that also destroyed the cities of Herculaneum and Pompeii. At that time, natural hazards were mostly seen as “acts of God(s)”. Instead, in today’s Anthropocene, extreme events coexist with two dichotomic (and rather simplistic) views: “disasters are natural” vs. “humans are to blame since they live in risky areas”. In this lecture, I present scientific and societal challenges associated with the increasing impact (from Plinius’ time to the Anthropocene) of humans on the spatial and temporal distribution of natural hazards. I also problematize and challenge myths, preconceptions and conventional wisdoms related with uncertainty, behavioral heuristics, expert vs. local knowledge, social power and inequalities. To this end, I review recent studies in various socioeconomic contexts, and across multiple hazards, with a focus on five events that have significantly influenced my research work: the 1963 Vajont Dam landslide, the 2004 flooding in Haiti and the Dominican Republic, the 2009 L’Aquila earthquake, the water crisis (Day Zero) during the 2015-2017 drought in Cape Town and the ongoing COVID-19 pandemic.
Flood monitoring using Sentinel-1 SAR images in Pearl River basin
Authors: Junliang Qiu , Cao Bowen , Tarolli Paolo , Zhang Wenxin , Yang Xiankun
Published: March 2021

The Pearl River Basin (PRB), as the second largest basin in China and one of the densely populated areas in China, is a critical region that exposes to high flood risks. Thus, it is indispensable to monitor the flooding patterns in PRB, so as to understand the flooding mechanism and better respond to the flood hazards. Previous studies about flood monitoring in PRB were mainly conducted by using gauging data of hydrological stations. However, the flood monitoring results would be prone to deviation in the region where the hydrological stations were sparse or without hydrological stations. Moreover, previous studies mainly focused on the urban flood in metropolis in PRB, neglecting the flood extents in rural area, in which the agriculture lands were constantly inundated by flooding water body. To monitor flood more comprehensively, this study will combine hydrological data, precipitation data with Sentinel-1 images to investigate spatial patterns of flood peak and flood extents in PRB. In addition, this study will also combine flood extents with land cover map to calculate the inundated areas of cropland during flood periods. This study will be valuable for flood mitigation, flood prevention and food guarantee in PRB.