bluuebunny/crossref_metadata_2025 huggingface dataset:
Preliminary results from the ICDP - DIVE project: Hole DT-1b (Ornavasso, Italy)
Authors: Müntener Othmar , Hétenyi György , Greenwood Andrew , Ziberna Luca , Zanetti Alberto , Pistone Mattia , Giovanelli Donato ,   DIVE Drilling Project Science Team
Published: February 2023

We report preliminary results from drill cores and logging from the ICDP Drilling the Ivrea-Verbano zonE (DIVE) project, Hole DT-1b in Ornavasso (Val d’Ossola, northern Italy). Characterized by pronounced geophysical anomalies, the exposed Ivrea-Verbano Zone in the Italian Alps represents an archetypal lower continental crust section. The first phase of DIVE is dedicated to the drilling and the petrological and geophysical characterization of the lowermost continental crust. Specifically, Hole DT-1b was set in the in the hinge zone of the Massone Antiform to explore the pre-Permian lithologies of the lower continental crust. Hole DT-1b was drilled using the diamond double tube continuous wireline coring method, from October 6 to December 10, 2022, and the retrieved rock cores were inspected and classified by the DIVE drilling project science team. Core recovery was effectively 100% throughout the entire drill hole. In total, 578m of the upper part of the lower continental crust in the Ivrea-Verbano Zone were drilled and cored.Here we summarize on site visual core descriptions and preliminary geophysical logging and microbiological investigations. The cores mostly consist of amphibolites and garnet-bearing metapelites with variable presence of migmatitic structures, and with local high and low temperature shear zones, pegmatitic dikes, and open fractures.Continuous monitoring of borehole fluids and gases (OLGA and miniRuedi devices, see EGU abstract by Dutoit and coworkers), and a suite of borehole logging measurements (see abstract by Li, Greenwood, Caspari and coworkers) were performed. They match very well the core logs performed on site (magnetic susceptibility and natural gamma radiation). The most prominent, directly observable deformation feature was a high-temperature foliation, with a dip angle between 30 and 60° in the upper part of the hole, becoming increasingly steeper in the deeper part.Along the entire drill hole fractures and open cracks were observed, some of them filled with precipitates of quartz, carbonates, sulphides and oxides. These fractures are potentially promising hosts for microbial communities and are currently under investigation. Additional samples for microbiological studies were taken every 20m from the drill cores and are currently cultivated for further investigations.Hole DT-1b provides detailed insights into the compositional, structural and geophysical variation of metasedimentary continental lower crust, including the distribution of sulphides. Relamination of metamorphic pelitic and mafic rocks may produce an important reservoir of sulphur bearing minerals in the lower continental crust. Further results emerging between abstract submission and the conference will be presented.
What if… we could observe the aurora in both hemispheres.
Authors: Halford Alexa , Liemohn Mike , Welling Dan , Ridley Aaron ,   MAAX Science Team
Published: February 2023

The aurora is a beautiful manifestation and tracer of the drivers and processes active in the interconnected geospace system. For decades we have stretched to find ways to use the aurora to gain a global view of our geospace system, most being ground-based. Ground-based measurements provide longevity in the northern hemisphere but are impacted by terrestrial weather and constrained by where there is accessible land. For a short few months, the Polar and IMAGE satellites periodically provided simultaneous images of the northern and southern aurora. From these few advantageous conjugate auroral zone observations, it was discovered that there are substantial asymmetries between the northern and southern hemispheres. Conjugate auroral features were found to exhibit different morphologies and are sometimes shifted by 10-20 ̊ in longitude. We have tried to gain insight through statistical studies of the aurora… but what questions could be answered if we observed the aurora in both hemispheres simultaneously? It has been 20+ years since NASA launched a space-based mission to image the aurora. Here we look to discuss a new mission idea focused on providing this genuinely global view, opening up pathways to answer large-scale system science questions. 
EYE-CLIMA: developing inverse modelling approaches for monitoring national GHG inventories
Authors: Winiwarter Wilfried , Peters Glen , Thompson Rona ,   EYE-CLIMA consortium
Published: February 2023

Emissions of greenhouse gases (GHG) reported by countries in their GHG inventories represent the central information used in international policies based on the Paris agreement and in the Global Stocktake process to help curb global GHG emissions. To maximize trust in these national emission inventories reported to the UNFCCC, procedures for quality control, quality assurance, and verification have been described in the IPCC 2006 national GHG inventory guidelines and extended further in its 2019 refinement. Quantifying emission fluxes via atmospheric measurements and inverse modelling provides an independent assessment of the inventories and can help determine the quality of national inventories and make improvements. While tested in scientific studies, routine applications of inverse modelling in national inventory reports are rare. As a new Horizon Europe project, EYE-CLIMA will perform inverse modelling of a range of important radiative forcers (methane, nitrous oxide, selected fluorinated gases, black carbon) as a monitoring tool on a national scale for selected European countries, together with national inventory agencies, to help develop complementary methods to ensure the robustness and lead to improvements in inventories. The presentation will lay out the overall project concept, including stakeholder involvement, and provide an overview on past experiences with inverse modelling approaches and strategies to implement them in a way useful for national inventory agencies.
Study of kinetic processes based on MMS/Cluster joint measurements in the vicinity of the plasma sheet boundary layer
Authors: Le Contel Olivier , Retino Alessandro , Chust Thomas , Steinvall Konrad , Alqeeq Soboh , Baraka Mohammed , Canu Patrick , Fontaine Dominique , Mirioni Laurent , Dandouras Iannis , Carr Christopher , Toledo-Redondo Sergio , Fazakerley Andrew , Doss Natasha , Daly Patrick , Kiehas Stefan , Nakamura Rumi , Khotyaintsev Yuri , Wilder Frederick , Ahmadi Narges ,   Joint Cluster/MMS team
Published: February 2023

On 28th of August 2018 at 5:30 UT, MMS and Cluster were located in the magnetotail at about 16 earth radii (RE). They both suddenly crossed plasma interfaces. Located near the post midnight sector, Cluster transitioned from a cold plasma sheet to a hot plasma sheet associated with a quasi-parallel earthward flow 800 km/s whereas MMS, located at 4 RE duskward of Cluster, transitioned from a similar cold plasma sheet to the lobe region via a very short period in a hot plasma sheet associated with a vortex-like signature. At 05:50 UT MMS returned to a hot plasma sheet and also detected a quasi-parallel earthward flow ~ 400 km/s and increased energetic ion and electron fluxes. We use measurements from both missions during this conjunction to describe the possible large scale dynamics of the magnetotail as well as some associated kinetic processes. Energetic particle (>50keV) measurements from the two missions are compared. Furthermore, at ion scales, we investigate the possible role of ion fire-hose instability in the plasma flow reduction. At electron scales, we analyze fast and slow non linear electrostatic waves propagating tailward which are detected in the so called electron boundary layer as well as in the hot plasma sheet. We discuss their possible generation mechanisms and link with the large scale dynamics of the magnetotail.
First results on induced seismicity and its source parameters during hydraulic stimulations in the Bedretto Underground Laboratory, Switzerland
Authors: Rosskopf Martina , Durand Virginie , Villiger Linus , Obermann Anne , Giardini Domenico ,   Bedretto Team
Published: February 2023

The Bedretto Underground Laboratory for Geoenergies and Geosciences (BedrettoLab) is a unique research environment in a tunnel in the Swiss Alps with an overburden of one kilometer. For a first experimental campaign in the context of enhanced geothermal reservoir creation (enhanced geothermal system, EGS), six 150-300 m long monitoring boreholes were drilled in the BedrettoLab and equipped with a multi-component geophysical monitoring system. The seismic sensors are composed of acoustic emission sensors, accelerometers and geophones to cover a magnitude range from nano to micro seismicity. An additional 400 m long stimulation borehole is equipped with a multi-packer system dividing it into 15 separate intervals of 8 to 55 m length.In the first phase, we performed characterization stimulations in eight intervals using comparable small amounts of injected fluid (350-14000 l) dependent on the length of the interval and their initial transmissivity. In the second phase, we are restimulating the intervals with higher injection volumes. The objective of these experiments is to improve our understanding of the hydro-seismo-mechanical response of the surrounding rock mass to hydraulic injections. For each interval, the seismic activity varies in number and magnitude and in its spatial and temporal evolution although comparable injection volumes were used. We interpreted the spatio-temporal evolution of event clouds together with the preconditions of the intervals, such as fracture network and transmissivity. Those preconditions can have a big impact on how the rock mass behaves when pressurized during hydraulic stimulations. Depending on the interval, event clusters are distinguished, for which first moment tensors are estimated. The moment tensors show different mechanisms not only for different intervals but also for different clusters. Finally, we compare the seismicity to other observables in the volume like stress and temperature measurements performed in monitoring boreholes to recognize fluid pathways and the response of the rock mass.
DIRECTED – Disaster Resilience for Extreme Climate Events providing Interoperable Data, Models, Communication and Governance
Authors: Steinhausen Max , Schröter Kai , Drews Martin , Cumiskey Lydia , Apel Heiko , Bagli Stefano , Bharwani Sukaina , Struck Julian , Bittner Daniel , Conradt Tobias , Gräler Benedikt , Genillard Christopher , Hochrainer-Stigler Stefan , Huszti Levente , Irvine Tracy , Kropf Chahan M. , Rønde Nielsen Emilie , Schweizer Pia-Johanna , Pancioli Valeria , Rutili Analia ,   DIRECTED project team
Published: February 2023

The recent droughts and unprecedented floods in Central Europe have revealed our vulnerability to extreme weather events. Besides climate change as a driver of more frequent and intensifying extreme events, demographic change and socio-economic development exacerbate severe impacts. International frameworks for disaster risk reduction (DRR) and climate change adaptation (e.g. Sendai framework for DRR, EU Strategy on adaptation to climate change) acknowledge the critical need for integrating risk governance, communication and operational mechanisms for coping with extreme climate events throughout the entire Disaster Risk Management cycle.DIRECTED aspires to foster disaster-resilient European societies by expanding our capabilities to communicate, utilise and exchange state-of-the-art data, information and knowledge between different actors. The project strives to boost the integration, accessibility and interoperability of models, facilitating knowledge sharing and improving dialogue and cooperation on all levels of Disaster Risk Management cycle. Four regional and municipal Real World Labs in the Capital Region of Denmark, the Danube Region, Emilia Romagna Region, Italy and the Rhine-Erft District, Germany, are at the centre of the bottom-up, value-driven co-development approach. The Real World Labs ensure the project continuously and actively involves key stakeholders in the development process and address topical problems of multi-hazard risk management and climate change adaptation to maximise the impacts of the DIRECTED project. Key to supporting interoperability will be the establishment of the DATA-FABRIC, an innovative, federated cloud platform that enables secure, flexible, discovery and sharing of all structured and unstructured data. DIRECTED is committed to promote the power of open data and open science in all of its research efforts.Through an interdisciplinary approach that brings together natural and social scientists, with data experts, local stakeholders as well as first and second responders DIRECTED builds lasting real world partnerships and leverages synergies for Disaster Risk Reduction and Climate Change Adaptation efforts in Europe.
Comprehensive intercomparison and evaluation of global upscaled foliar trait maps
Authors: Dechant Benjamin , Pavlick Ryan , Schneider Fabian , Townsend Philip ,   sTRAITS  working group
Published: February 2023

Global trait maps of specific leaf area (SLA), leaf nitrogen (N) and phosphorus (P) contents have been generated using a wide range of data-driven upscaling approaches. We comprehensively studied their consistency and agreement with sPlotOpen data at 0.5 degee grid cells. For this, we developed approaches to separate the maps into their plant functional type (PFT) components by taking into account within-grid-cell heterogeneity and stratified sPlotOpen data by PFT.We found that despite many differences in the upscaling approaches, the maps fall into two groups: One group using remote sensing based, fractional PFT cover  in the upscaling, while the other did not. Spatially, the main differences between the two groups are located in areas of high within-grid-cell trait heterogeneity and these areas dominate global trait variations due to the combined effects of fractional PFT cover and trait differences between-PFTs.The agreement of upscaled maps with sPlotOpen data strongly depends on the way sPlotOpen data are scaled to the grid cell. When using a similar scaling approach as the upscaling approaches a similar level of agreement can be observed for both groups of maps. However, only the maps that used PFT information could capture main features of between-PFT differences, especially the low values of SLA and N in evergreen needleleaf forests. Within-PFT trait variations of upscaled maps partly showed similar patterns as sPlotOpen data when aggregated to latitudinal averages but considerable differences remain and the evaluation is challenging without having the original maps per PFT. We conclude that fractional PFT cover contains essential information for capturing global, top-of-canopy trait patterns using upscaling approaches at moderate to coarse spatial resolution.
A new data-driven map of peat distribution predicts substantial unknown peatland areas in Amazonia.
Authors: Hastie Adam ,   Amazonian peatlands consortium
Published: February 2023

Tropical peatlands, the most carbon dense terrestrial ecosystems in the world, are a substantial but highly uncertain component of the global carbon cycle with wide-ranging estimates of their total area (441,025 -1,700,000 km2), and total below-ground carbon (105-215 Pg C). Protecting and restoring tropical peatlands can make a significant contribution to limiting CO2 emissions and global warming, but policy instruments such as REDD+ and Nationally Determined Contributions to the Paris Agreement must be informed by high resolution maps of peatland distribution if they are to be effective.In regions such as South East Asia, we have relatively high confidence in existing peatland estimates, supported by decades of research and field data. There have also been recent intensive field efforts in regions such as the Congo basin and Peruvian Amazonia, which have driven the development of more accurate regional peatland and below-ground carbon maps. However, substantial gaps remain in our understanding of the distribution of peatlands and their carbon store in some key tropical regions, including most of tropical South America.Here we collate around 2,000 ground reference points in and around Amazonian peatlands, including data from Peru, Colombia, Brazil and Ecuador. These data are used to drive a high-resolution machine learning model predicting peatland distribution across the Amazon basin. We estimate a total peatland extent of approximately 200,000 km2, greater for example than that of the Congo basin, with Brazil hosting the greatest predicted area. However, a lack of field data, particularly across some regions of Brazil, Bolivia and Venezuela, means that substantial uncertainties remain. We predict large areas of peatland in the Rio Negro basin which overlap with predicted maps of Campinarana or white sand forest habitats, but we do not know what proportion of these ecosystems represent true peatlands and how deep and carbon dense their peat could be. We discuss remaining uncertainties and call for expanding sampling in these ecosystems to better understand these potentially extensive peatlands. The past response of tropical peatlands to climate and land-use change, particularly in terms of carbon accumulation, also requires urgent investigation given that the central and eastern Amazon is projected to undergo more significant climatic change than the western basin.
Planetary-scale MLT waves diagnosed through multi-station methods
Authors: He Maosheng
Published: February 2023

Most experimental investigations on planetary-scale waves in the mesosphere lower thermosphere (MLT) region are based on single-station or -satellite spectral analysis methods, which are subject to intrinsic spectral aliasing/ambiguity. To conquer the aliasing, the author developed and implemented dual- and multi-station spectral methods in a series of recent works. These methods were implemented on meteor radar observations and surface magnetometer observations. A variety of waves were discovered or investigated in terms of seasonal variations and responses to sudden stratospheric warming events, including lunar and solar tides (migrating and non-migrating), Rossby wave normal modes, quasi-two-day waves, ultra-fast Kelvin waves, and secondary waves of wave-wave nonlinear interactions between the previous waves. The current paper uses synthetic data to illustrate the three methods and reviews comparatively these methods and results in plain language.
A wildfire vulnerability index for buildings in Austria
Authors: Papathoma-Koehle Maria , Hausharter David , Schlögl Matthias , Fuchs Sven
Published: February 2023

Recent events have clearly shown that wildfires may occur in areas that until now have not experienced large wildfires and the associated consequences (e.g. Scandinavia, Siberia, Austria, etc.). There is a need to understand the risk posed by wildfires and develop tools for the assessment of the vulnerability of assets such as buildings and infrastructure. Building quality and design standards are important not only because building loss is costly but also because robust buildings may offer shelter when evacuation is not possible. Studies aiming at the analysis of wildfire vulnerability for the built environment are limited.  We present a new wildfire vulnerability index for buildings in Austria based on a choice of vulnerability indicators and expert judgement. Vulnerability indicators express characteristics of the buildings and their surroundings that influence their vulnerability to a hazardous process. A list of indicators based on the existing literature has been used together with an expert panel to decide which indicators may be relevant and what is their importance in controlling vulnerability. The indicators and their weights are aggregated into a wildfire vulnerability index which can be assigned for each building located in the wildland urban interface (WUI) zone. This index is related to information such as the structural building type, the roof type, material and shape of the roof, the inclination of the ground, the surrounding vegetation, the material of the shutters and the ground covering. The resulting vulnerability and its spatial pattern may guide decisions, strategies and vulnerability reduction activities that will increase the resilience of communities to this emerging risk. The index may be used by decision-makers, emergency services, homeowners and insurance companies to visualise physical vulnerability to wildfire.
Towards a theory of carbon allocation based on eco-evolutionary optimality principles
Authors: Ding Ruijie , Nóbrega Rodolfo , Prentice Iain Colin
Published: February 2023

Understanding the distribution of assimilated carbon (C) among different plant parts is essential in explaining the responses of multiple functional traits to climate change. C allocation is not adequately represented by current ecosystem models, and the general explanatory framework of C allocation with environmental conditions is fragmented. Machine learning approaches applied to large data sets have failed to reveal general principles underlying C allocation. Here, we analyse a large global set of data derived from several previous compilations to test eco-evolutionary optimality hypotheses that potentially account for the environmental controls on root:shoot biomass ratios (R:S) in both woody and herbaceous plants. These controls are expressed in terms of statistical predictors describing aspects of the environment relevant to plant stimuli. Thus, for example, we consider growing-season temperatures rather than annual means; and we include modelled gross primary production (GPP) and root-zone water capacity (RZWC) among the candidate predictors. We hypothesize that increasing gross primary productivity (GPP) permits increased C allocation to stems, automatically reducing R:S. Demand for C allocation to roots is less in warmer climates because of faster nutrient turnover in warmer soils. On acid soils, the need for roots to take up nutrients is reduced due to more open stomata and thus lower optimal photosynthetic capacity. More C is allocated to roots in climates with seasonal mismatches between water supply and demand, where increased RZWC is required to maintain water availability during the dry season. On sandy soils, low water-holding capacity implies a need for further investment in roots for water uptake. Our analysis broadly supports these hypotheses, and an ordinary least-squares multiple linear regression model explains nearly three-quarters of the observed global variation in R:S. However, the allocation strategies of woody and herbaceous plants differ. The expected negative relationship of R:S to growth temperature, and the positive relationship of R:S to sand content, are shown only in woody plants; while the expected positive relationship of R:S to soil pH is shown only in herbaceous plants. These findings constitute a first step towards a theory of C allocation response to resource availability, and a parsimonious model for inclusion in next-generation C cycle models.
Moisture sources and pathways of annual maximum precipitation in the Lancang-Mekong River Basin
Authors: Zhang Shuyu , Liu Junguo , Chen Deliang , Gong Guoqing , Zhang Gengxi
Published: February 2023

Extremely heavy precipitation leads to increasingly frequent floods, landslides, debris flow, storm surges, and other natural hazards in the Lancang-Mekong River basin (LMRB) that causes large amounts of economic loss and affected millions of residences. This study analyzed the spatial-temporal characteristics of the annual maximum precipitation (R1X) of the LMRB and identified the moisture sources and pathways conducive to the occurrences of these extreme precipitation events during 1965-2021. Results show that the R1X of the upstream region concentrated in July, while that of the downstream region mainly occurred from August to September. The regional mean R1X shows an increasing trend, especially after 2010. The moisture pathways of the historical R1X were identified through a Lagrangian back trajectory model and were classified into three clusters by the Self-Organize Map: West Pacific Ocean (WP), local evapotranspiration, and Bay of Bengal (BOB). BOB provided the main moisture source to the R1X of the LMRB which contributes 68.3% of the trajectories, while the local evapotranspiration and WP account for 20.4% and 11.3%, respectively. For most areas downstream of LMRB, the moisture from the BOB transported through the cross-equator flow is the main moisture pathways patterns. For the upstream of LMRB, the evapotranspiration from the local and neighboring terrestrial and oceanic surfaces provides the main moisture sources. For the east area of the downstream, R1Xs are high and mainly resulted from tropical cyclones bringing large amounts of moisture from the WP to the LMRB. As tropical cyclones moved northward under climate change, more extreme precipitation over the LMRB was fed by the moisture from WP, while those from the BOB is decreasing with the slowdown of cross-tropical flows.
Layered structure of near equatorial, ring current density and its ionospheric coupling: multi-spacecraft observations
Authors: Tan Xin , Dunlop Malcolm , Yang Yanyan , Dong Xiangcheng , Du Yingshuai
Published: February 2023

The Earth’s ring current forms a complex current system at the boundary of the inner magnetosphere. It is highly dynamic because of the interaction between the solar wind with the Earth's magnetosphere (the influence of space weather), while its morphology depends on the nature of the magnetospheric-ionospheric (M-I) coupling, generating field-aligned currents (FACs). Its behaviour can therefore have a huge impact on the terrestrial environment. According to Ampere's law, these currents can be directly measured by perturbations in the magnetic field using multi-spacecraft observation techniques. We have analyzed the magnetic field data from the four MMS spacecraft in their small-sale configuration to obtain the in-situ current density and have carried out statistical analysis from several years of data. The form of the current density distribution and its changing nature has been investigated. Our results show that the current density exhibits a three-dimensional layered structure in the ring current region. The significant westward current on the day side flows to higher magnetic latitudes and complete closure there rather than to the magnetic equator. There are some differences between geomagnetic quiet period and storm period on current density, but the basic spatial structure remains similar and compares well with previous space mission data. Comparison with Swarm data at low Earth altitudes, we found that the stratification is consistent with the distribution of the R2 field-aligned currents seen both adjacent to the ring current and at ionospheric altitudes (at Swarm). In addition, significant continuous eastward currents exist in some latitudes and some regions, indicating the complexity of the ring current. Some of them can be explained by the formation of banana currents.
Profiling, instead of ranking, academics with the multi-metric academic profile ProAc
Authors: Crameri Fabio
Published: February 2023

Scientific evaluation built upon numeric metrics is advantageous: It’s time effective (saving precious research time), fair (directly comparable and less biased by subjective reviewer opinions), and does not require, and cannot be altered by, individual linguistic or other skills (unlike written CVs, for example).The ruling metric, the h-index, is currently misused widely to rank academics based upon numbers of papers (only papers) published and number of received citations: Who published the most adequately cited papers wins permanent jobs, project funding, and awards. Something that is most easily achieved by an academic, who blends in, and works in, an established research entity and along an established line of research, and does not share methodologies.I believe that, in stark contrast, a multi-metric profile can end the academic detour past high-quantity low-quality science publication (e.g., “publish or perish”), all-dominant research camps, irreversible scientific views, and inaccessible science. If designed carefully, a numeric multi-metric profile provides a multitude of critical academic incentives. As such it offers a unique opportunity to foster academic diversity, boost disruptive science, and rebuild the bridges with the general public (i.e., academia’s stakeholder); likely the most sensible way forward for science.Today, the quality of research can – numerically – be valued higher than its quantity; the openness of research, methodologies, and tools can be represented by a single, if also brutally honest number; pivotal academic contributions towards method and tool development, and even to some degree, teaching, and outreach can be recognised in quantified form.Such a multi-metric professional profile characterises individual academics, instead of purely (and poorly) ranking them. Assembling complementary team or project members becomes easier; more successful research likelier. Individual strengths and weaknesses become clear and allow academics (and supervisors) to make use of them and take steps to improve.Here, I will introduce, outline, and *make available* the first, ready-to-be-used version of the academic profile, ProAc. It is geared towards making academic evaluation fairer and more time-effective, and science the best it can be: diverse, collaborative, disruptive. ProAc is neither perfect nor complete – it never will be. This is why it is designed for continuous improvements and adjustments. ProAc is crafted with all my heart and your gain in mind, but also with the hope for your feedback and support down along its exciting roadmap.With love, fury, and a bit of coding. 💫
R-tipping and N-tipping in a vegetation pattern model
Authors: Vanderveken Lilian , Martínez Montero Marina , Crucifix Michel
Published: February 2023

Vegetation in semi-arid regions has adapted to low rainfall by organizing itself in patterns, which can be described by reaction-diffusion equations that include local positive feedback (e.g. infiltration) and non-local mitigation (e.g. lateral water flow). This allows the vegetation to survive in lower rainfall conditions and creates multiple stable states, meaning that for a fixed amount of rainfall, the vegetation can exist in different patterns. It is possible to identify these different equilibrium states and to create a bifurcation diagram for the model.As the climate changes, there is likely to be a shift in the rainfall patterns in the Sahel, although it is not yet clear if there will be an increase or decrease in precipitation. In this context, we use the vegetation pattern model and its bifurcation diagram to understand how it will respond to slow and fast changes in rainfall, and explore the possibility of rate-induced tipping (R-tipping). On the other hand, rainfall, land use and fires have a stochastic component, which we represent by adding two types of noise to the system: homogeneous and heterogeneous. This noise can cause a switch from one stable equilibrium to another, known as N-tipping, depending on the type of noise applied. The vegetation pattern is more stable to homogeneous noise than heterogeneous, but when it tips the homogeneous noise kill all the vegetation.Understanding how patterned systems respond to changing environments and noise is critical for predicting the future evolution of various patterned systems globally, not just vegetation in the Sahel.This project has received funding from the European Union’s Horizon 2020 research and innovation programme (grant no. 820970). 
Widespread Slope Movements in Countrywide InSAR Mapping of Iceland
Authors: Jónsson Sigurjón , Cao Yunmeng
Published: February 2023

We report on countrywide InSAR deformation mapping of Iceland using all the available Sentinel-1 radar data (Summer/Fall 2015-2021) from three parallel and overlapping descending and three ascending orbit tracks, yielding a complete countrywide coverage for both look directions. The total number of satellite passes for each of the six orbit tracks is about 170, meaning that over 1000 data sets were used, from which we processed around 8700 interferograms (multilooked to 100 m x 100 m pixels). Atmospheric signals in the data were reduced using a two-step correction approach based on global atmospheric model outputs and information about the stochastic characteristics of atmospheric noise. We then solved for the time-series of each of the six data sets and inverted for near-east and near-vertical time-series, assuming that north ground displacements are small. Large-scale displacements in Iceland are dominated by the plate motion and by glacio-isostatic adjustment. The results show how the width of the plate-boundary zone varies from being relatively narrow in Reykjanes to more distributed deformation in the Eastern Volcanic Zone. The glacio-isostatic uplift reaches a maximum of ~3 cm/year in central Iceland and appears to accelerate during the observation period. These large-scale horizontal and vertical displacements can be removed with a model of the plate motion, plate-boundary deformation and glacio-isostatic adjustment, leaving only local deformation signals in the residual displacement rate map, e.g., at central volcanoes and areas of geothermal exploitation. Widespread slope movements are also evident in the residual deformation map. Almost all east-facing slopes are moving eastward and west-facing slopes westward. This deformation is seen all over Iceland and amounts to a few mm/year, with faster rates at some known landslides. Example areas include northwestern and central-north Iceland where 5-10 mm/year movement rate is found on many of slopes, as well as the Western Fjords and Snæfellsnes peninsula. Recent slope failures in North Iceland in 2021 and 2022, which resulted in mudslides with road closures and some structural damage, occurred on slopes that can be seen moving during the years before the failures. However, no anomalous motion is detected at these slopes in the months before the failures; they are just slowly creeping like many other slopes in this area. In Summary, our results show that InSAR data are effective to map country-wide ground velocities and velocity changes as well as local deformation signals and transients at volcanoes and geothermal areas.  The results also show that slopes all over Iceland are subject to steady gravitational soil creep amounting to several mm/year, with higher rates observed in many areas where geomorphologically landslides can be identified in the landscape.
Early warnings of the transition to a superrotating atmospheric state
Authors: Williamson Mark
Published: February 2023

A superrotating atmosphere, one in which the angular momentum of the atmosphere exceeds the solid body rotation of the planet occurs on Venus and Titan. However, it may have occurred on the Earth in the hot house climates of the Early Cenozoic and some climate models have transitioned abruptly to a superrotating state under the more extreme global warming scenarios. Applied to the Earth, the transition to superrotation causes the prevailing easterlies at the equator to become westerlies and accompanying large changes in global circulation patterns. Although current thinking is that this scenario is unlikely, it shares features of other global tipping points in that it is a low probability, high risk event.Using an idealized general circulation model developed for exoplanet research here at Exeter, we simulate the transition from a normal to a superrotating atmospheric state. We look at the changes in typical early warning indicators of tipping which show critical slowing down as well as oscillatory behaviour close to the transition. Inspired by the studies of phase transitions we also look at the critical spatial modes and correlation lengths close to the transition.
A regional flow duration curve-based approach for predicting sediment yield at ungauged sites
Authors: Sathya Abhijith , Srinivas Venkata Vemavarapu
Published: February 2023

Sediment yield estimates in river basins are essential for studies related to river morphology, water quality modeling, development of erosion control and management plans, and design of water control structures (e.g., dam, barrage). In data-scarce scenarios, calibration and validation of numerical models for estimating sediment yield become challenging. A regional FDC (Flow Duration Curve)-based methodology is proposed for predicting the sediment yield at ungauged locations in river basins. Its effectiveness was investigated through Jackknife cross-validation experiment on the frequent flood-prone Mahanadi basin, considering daily records of 13 sediment and flow monitoring stations for the time period 1980-2019. A set of 34 catchment-related attributes derived based on morphology, climate, landuse, and location were considered. Potential attributes influencing flows in the basin were identified as those having significant correlations with flow quantiles corresponding to 15 chosen exceedance probabilities (P=0.1, 0.5, 1, 5, 10, 20, 30, 40, 50, 60, 70, 80, 90, 95, and 99). The identified attributes include (i) catchment area, (ii) number of streams, (iii) minimum elevation, (iv) basin relief, (v) the percentage of area classifiable as grassland, and (vi) longitude. To arrive at sediment yield at an ungauged location, first FDC corresponding to the location is derived using regression relationships fitted between each of the 15 flow quantiles and the potential attributes of gauged sites in the region. The relationships were developed using the best subset regression analysis. Subsequently, the daily discharge and daily sediment time series at the ungauged location were derived from the FDC. For this purpose, the rating curve parameters for the ungauged site were obtained from its neighboring sites in the attribute space, through a proposed strategy. The performance of the proposed approach in predicting the discharge and sediment time series was found to be effective when assessed in terms of various performance measures, which included Nash-Sutcliffe efficiency, and Kling-Gupta efficiency.
Northern Hemispheric extratropical cyclones during glacial times: impact of orbital forcing and ice sheet height
Authors: Raible Christoph C. , Messmer Martina , Buzan Joanthan , Russo Emmanuele
Published: February 2023

Extratropical cyclones are a major source of natural hazards in the mid latitudes as wind and precipitation extremes are associated to this weather phenomenon. Still the response of extratropical cyclones and their characteristics to strong external forcing changes is not yet fully understood. In particular, the impact of the orbital forcing as well as variations of the major ice sheets during glacial times on extratropical cyclones have not been investigated so far.  Thus, the aim of this study is to fill this gap and to assess the impact of orbital forcing and northern hemispheric ice sheet height variations on extratropical cyclones and their characteristics during winter and summer. The main research tool is the Community Earth System Model CESM1.2. We performed a set of time slice sensitivity simulations under preindustrial (PI) conditions and for the following different glacial periods: Last Glacial Maximum (LGM), Marine Isotopic stage 4 (MIS4), MIS6, and MIS8. Additionally, we vary the northern hemispheric ice sheet height for all the different glacial periods by 33%, 66%, 100% and 125% of the ice sheet reconstructed for the LGM. For each of the simulations the extratropical cyclones are identified with a Lagrangian cyclone detection and tracking algorithm, which delivers a set of different cyclone characteristics, such as, cyclone frequency maps, cyclone area, central pressure, cyclone depth, precipitation associated to the extratropical cyclones as well as extremes in cyclone depth and extratropical cyclone-related precipitation. These cyclone characteristics are investigated for the winter and the summer season separately.Preliminary results show that the extratropical cyclone tracks are shifted southwards on the Northern Hemisphere during the winter season. This has rather strong implication for the Mediterranean, with an increase of precipitation during glacial times over the western Mediterranean. This increase is modulated when changing the ice sheet height as extratropical cyclone tracks shift further south with increasing northern hemispheric ice sheet height. The orbital forcing shows a higher impact during the summer season, where mean precipitation is further reduced over Europe when comparing MIS4 and MIS8 with LGM. The role of the cyclones for these changes in summer needs to be assessed as well as the implication in the North Pacific.
Harmonics multiple to the driving frequency of damped bilinear oscillators
Authors: Pasternak Elena , Dyskin Arcady , Pevzner Roman , Gurevich Boris
Published: February 2023

Field observations show that power spectra of the response to high amplitude harmonic excitation contain peaks at frequencies multiple to the driving frequency, e.g. [1]. This phenomenon is conventionally attributed to the effect of mechanical non-linearity of the Earth’s crust. Given that there exist various types of non-linearity it is important to identify the types of non-linearities that can produce multiple harmonics in response to high power excitation and thus ensure the correct interpretation of the monitoring data.One type of non-linearity capable of producing multiple resonances is bilinearity of stiffness, the simplest representation of which is a bilinear oscillator – the oscillator with different stiffnesses for compression and tension. In the Earth’s crust the role of bilinear oscillators can be played by pre-existing fractures initially closed by the in-situ compression but capable of being opened by the tensile phase of the applied high amplitude harmonic excitation.Bilinear oscillators possess multiple resonances, e.g. [2], however these are multiples of the natural frequency. We note that extreme damping effected by the presence of fluids in fractures and porous rocks can quickly eliminate the effect of the natural frequency leaving only the stationary oscillations with the driving frequency in each linear (tensile or compressive) stage of oscillations. The transition from one stage to another is characterised by short transients, which gives rise to multiple spectral peaks. This mechanism is investigated in asymptotics of high damping ratio. It is shown the existence of the following spectral peaks: if f0 is the driving frequency, the peaks will be observed at 2f0, 3f0, 5f0 and further at all odd multiples of f0.The theory developed is essential for identifying the prevailing mechanisms of non-linearity in the Earth’s crust and determining their parameters.1. Yurikov, A., B. Gurevich, K. Tertyshnikov, M. Lebedev, R. Isaenkov, E. Sidenko, S. Yavuz, S. Glubokovskikh, V. Shulakova, B. Freifeld, J. Correa, T.J. Wood, I.A. Beresnev and R. Pevzner, 2022. Evidence of nonlinear seismic effects in the earth from downhole distributed acoustic sensors. Sensors 2022, 22, 9382.2. Dyskin, A.V., E. Pasternak and E. Pelinovsky, 2012. Periodic motions and resonances of impact oscillators. Journal of Sound and Vibration 331(12) 2856-2873.Acknowledgement. EP, AVD and BG acknowledge support from the Australian Research Council through project DP190103260. RP and BG acknowledge financial support from the Australian Department of Industry, Science and Resources for the 2021 Global Innovation Linkage (GILIII000114) grant and the Sponsors of the Curtin Reservoir Geophysics Consortium.
Health Risk Assessment and Source Apportionment of Elemental Particulate Contents from a South Asian Future Megacity
Authors: Ibrahim Muhammad , Aslam Afifa , Mahmood Abid , Alvi Muhammad , Jabeen Fariha , Tabassum Umara
Published: February 2023

Many factors cause air pollution in Pakistan, which poses a significant threat to human health. Diesel fuel and gasoline motor vehicles, as well as industrial companies, pollute the air in Pakistan's cities. The study's goal is to determine the level of air pollution in a Pakistani industrial city and to establish risk levels for the health of the population. We measured the intensity of air pollution by chemical characterization and examination of air samples collected at stationary remark sites. The PM10 levels observed at all sampling sites including residential, commercial, high traffic and industrial areas were well above the limits imposed by Pakistan EPA, United States EPA, and WHO. We assessed the health risk via chemical factors using methodology approved for risk assessment. All Igeo index values greater than one were considered moderately contaminated or moderately to severely contaminated. Heavy metals have a substantial risk of acute adverse effects. In Faisalabad, Pakistan, there was an enormously high risk of chronic effects producing of heavy metal acquaintance. Concerning specified toxic metals, intolerable levels of carcinogenic risks have been determined for the entire population. As a result, in most of the investigated areas of Faisalabad, the indices and hazard quotients for chronic and acute exposure exceeded the permissible level of 1.0. In the current study, re-suspended roadside mineral dust, anthropogenic exhaust emissions from traffic and industry and industrial dust were identified as major emission sources of elemental particulate contents. Because of the unacceptable levels of risk in the research area, it is strongly suggested that a comprehensive study of the population's health status as a result of air pollution should be conducted for policies to be developed against these risks.
Mapping Cambodian Wetlands with Satellite Imagery and Google Earth Engine’s Machine Learning Algorithm.
Authors: Darbari Vasudha , Christopher Hackney , Grigorios Vasilopoulos , Rodney Forsters , Dan Parsons
Published: February 2023

The wetlands and lakes that make up more than 30% of Cambodia's terrain are home to a diverse range of resources and biodiversity. More than 46% of the population lives and works in these wetlands while 80% of the local population relies on their vital resources for sustenance such as fish, food, water and vegetables. This makes Cambodia one of the nations with the highest reliance on wetland and lake ecosystems in the world. On-going development in the region has boosted the rates of  urbanization. Urban expansion has deteriorated wetland ecosystems through land reclamation and infilling projects as well as hydrological and sediment cycle disruptions. It has also increased the demand for mined sand from the Mekong River. Mapping and monitoring the extent and distribution of wetland ecosystems in order to quantify the impact of human activities on these vital areas is critical for maintaining the ecological balance and promoting the sustainable development of an extensively eco-service dependent country such as Cambodia. In this study we combine spaceborne multispectral and radar remote sensing datasets with machine learning classification models and algorithms within the Google Earth Engine to monitor the changes observed in Cambodian wetlands through time. Our classifier is trained by comparing Sentinel 1 Synthetic Aperture Radar data to corresponding multispectral images captured from Landsat. We then use the classifier to monitor wetland extent through time from 1989 to present using merged Landsat 5 and 8 databases. With our maps and areal statistics, we identify the spatio-temporal trends and changes in wetland cover linked to climatic patterns and local anthropogenic influence connected to sand mining from the Mekong River and land infilling. In the last 15 years, about half the country’s wetlands have disappeared, with 15 out of 25 lakes near the capital completely infilled with sand that can be clearly observed with analysis of satellite data.