bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of AMR on the advanced magnetized CME model
Authors: Baratashvili Tinatin , Poedts Stefaan , Verbeke Christine
Published: March 2022

Coronal Mass Ejections (CMEs) are the main drivers of interplanetary shocks and space weather disturbances. One of the key parameters that determine the geo-effectiveness of the CME is its internal magnetic configuration. Strong CMEs directed towards Earth can have a severe impact on our planet and their prediction can mitigate possible damages. 

 

The novel heliospheric model Icarus, which is implemented within the framework of MPI-AMRVAC (Xia et al., 2018) introduces new capabilities to model the heliospheric wind and real CME events. Advanced techniques, such as adaptive mesh refinement and grid stretching are implemented. By imposing these techniques, we avoid cell deformation in the domain and only the necessary/desired areas are refined to higher spatial resolutions (and coarsened again when the high resolution is no longer necessary, e.g. behind a travelling shock wave). The refinement and coarsening conditions are controlled by the user. These techniques result in optimised computer memory usage and a significant speed-up, which is crucial for forecasting purposes. 

 

In order to model the magnetic field of the CME and its interaction with the solar wind, the Gibson and Low model is implemented in Icarus. In order to assess the ICARUS model capabilities to predict the solar wind conditions in the heliosphere, especially at L1, we consider a real CME event.  Further, we perform a comparison of the results of the existing Linear Force-Free Spheromak model and the new advanced model. To perform the full comparison we compare the time series data at L1 and other satellites, while we also monitor the time that simulations require to model the heliospheric wind and CME events. 

 

The solution mesh refinement is applied to the CMEs in order to model its arrival time and interior magnetic field better. To analyse the results, the radial, longitudinal and latitudinal components of the magnetic field are compared to the original EUHFORIA simulations and the observed data. As a result, the new magnetized model gives an opportunity to model the CME better and a bigger range of parameters to investigate to model the event as accurately as possible.  

 

This research has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 870405 (EUHFORIA 2.0).
Deep ice and mineral dust: the case of the TALDICE ice core
Authors: Delmonte Barbara , Baccolo Giovanni , Maggi Valter , Frezzotti Massimo
Published: March 2022

Mineral dust archived in polar ice cores can be used to document past atmospheric circulation variability and past climate conditions over the dust source areas. Thanks to its relative immobility and stability, eolian dust concentration has been used to synchronize deep ice cores as well as ice stratigraphies and marine sediment records. However, mineral impurities in deep ice can be affected by post-depositional physical and chemical alterations, deriving from small-scale relocation of dust grains and subsequent alteration in acidic micro-environments.

By applying a set of different techniques spanning from dust concentration and grain size to iron mineralogy and elemental composition, here we provide evidence of in situ dust physical and chemical alterations observed below 1000 m depth in the 1620-m deep TALDICE ice core drilled at Talos Dome (peripheral East Antarctica, 72°49’S, 159°11’E; 2315 m a.s.l.). Results highlight significant dust aggregation and alteration of Fe-minerals with englacial precipitation of neo-formed jarosite, occurring in parallel with the decline of ferrous minerals and depletion of some major elements. Therefore, below 1000 m depth the TALDICE dust record can be considered partly affected by acidic-oxidative weathering resulting from the interaction of dust particles with highly saline acidic brines. Although limited to only one specific site, this study opens new issues concerning the interpretation of climate signals in the deepest part of ice cores.
Experimental laboratory setup for identification and quantification of transported soil particles in subsurface flows
Authors: Kögler Laura , Iserloh Thomas , Helmer Alina , Ruby Andreas , Marzen Miriam , Seeger Manuel , Ries Johannes B.
Published: March 2022

There is a knowledge gap concerning the identification and quantification of transported soil particles in subsurface flows. If these soil particles reach relevant amounts, protective measures against soil erosion applied on the surface may be partially ineffective, and the soil may degrade further and unnoticed. In consequence, there is a need to develop a method to determine this subsurface particle transport in situ. A laboratory flume experiment was developed to examine the processes of fine soil material transport as well as the development of sediment traps for in situ measurements. Since, steep-slope vineyard soils are especially prone to subsurface flows they were subject of first investigations: The shallow steep-slope vineyard soils of the Mosel wine region are mainly developed from Devonian argillaceous schists and Pleistocene terrace sediments. Among the main physical characteristics are a very high rock fragment content and a loose surface layer over a strongly compacted layer caused by the combined action of tillage and weathering. This structure is presumably prone to subsurface flows within the upper horizon, especially in periods of very high soil moisture. The results of this laboratory experiment clearly confirm the presence of subsurface particle transport and the applicability of a sediment trap prototype consisting of a relatively simple and low-cost drain structure. 
Emulating spatially resolved annual maximum temperatures of Earth system models using MESMER-X 
Authors: Quilcaille Yann , Gudmundsson Lukas , Beusch Lea , Hauser Mathias , Seneviratne Sonia
Published: March 2022

Emulators of Earth System Models (ESMs) are complementary to ESMs, in that they provide climate information with reduced computational costs. However, climate extremes, one of the most impactful consequences of climate change, remain challenging to emulate in all of their aspects. Here, we propose a method for the emulation of local annual maximum temperatures, with a focus on reproducing essential statistical properties and correlation in space and time. The Modular Earth System Model Emulator for Regional eXtremes (MESMER-X) is based on sampling from the generalized extreme value distribution and we show quantitatively that the resulting emulations of annual maximum temperature can reproduce the temporal evolution and spatial patterns of the underlying ESM simulations. Given the general design of the emulator and the good performances for annual maximum temperatures, the proposed methodology can be applied to other indicators of climate extremes, illustrated here with an indicator of fire weather.
Development of a novel approach to assess the risk of physical clogging at managed aquifer recharge sites
Authors: Lippera Maria Chiara , Werban Ulrike , Rossetto Rudy , Vienken Thomas
Published: March 2022

Increasing aquifers' recharge and storage is of great importance in addressing challenges posed by climate change and growing water demand. Managed Aquifer Recharge (MAR) technologies may ensure water supply for agriculture and diminish impacts from groundwater overexploitation. The expansion of MAR solutions in Europe still requires the implementation of these waterworks at their maximum efficiency. Physical clogging is one of the main bottlenecks for these technologies. In spreading methods, during water recharge, eroded clays from surface runoff reach the infiltrating surface and intrude into the soil matrix, decreasing the basin infiltration capacity over time. The resulting loss in performance increases the operation and maintenance (O&M) costs and, in extreme cases, can lead to the MAR site's abandonment. Thus, it is vital to assess the risk of physical clogging during the MAR planning phase, extending the MAR scheme lifespan and minimising O&M costs. Our study aims to develop a comprehensive model for physical clogging transferable to multiple MAR sites, based on the characterisation of the sediment matrix and MAR operations. To achieve this, we built a semi-empirical 1D numerical model for physical clogging. Evolution in soil permeability via the Kozeny-Carman equation is computed in function of depth based on the input of fines into the soil matrix and the porous media characteristics. The vertical distribution of fines is derived through a general relationship from a systematic review of multiple studies in the literature. The model allows computing the evolution in infiltration rates over time for the MAR site and the depth of soil to be treated to restore infiltration efficiency. Preliminary validation at the field scale is conducted at a MAR infiltration basin in Suvereto, Italy. To spatially apply the model, zoning is performed through an electromagnetic induction (EMI) survey, defining areas with similar soil properties. Values of hydraulic conductivity near saturation and soil samples were collected to characterise the sediment matrix and fines content for the entire basin. Predictions of the expected decrease in infiltration capacity for spreading methods assists maintenance scheduling and reduce O&M costs for the specific site. The proposed model for physical clogging can serve as a tool for decision support when exploring a set of design alternatives prior to MAR construction.
The art-science interface: making York's air pollution visible
Authors: Bryant Daniel , Nattress Clare , Hamilton Jacqui
Published: March 2022

Airborne particulate species less than 2.5 micrometers in diameters known as PM2.5 are considered to be the most deadly form of air pollution, contributing to millions of premature deaths per year globally. However, due to the small size of these damaging airborne particulate species drawing public attention to the issue is challenging. This study aims to increase the public awareness of PM2.5 through an art-science collaboration. Conceptual artist Nattress uses her bicycle as a performative tool to pedal on low and high infrastructure routes around the city of York, UK. The roads around the circumference of the University of York and York St John University are known highly polluted areas that are often heavily congested. The bicycle was equipped with a MiniVol TAS sampler and a Plume Labs Flow 2 sensor gathering data over the course of three months. The filters collected were extracted and analysed by atmospheric scientist Bryant through an established method used for PM2.5 filter samples, using ultra-high-performance liquid chromatography, high-resolution mass spectrometry to identify known compounds within the samples. The process of collection and extraction were documented and the filters also photographed and investigated under a microscope.

This arts-science collaboration seeks to uncover if there are any striking differences in air pollution levels on regular bus routes to both campuses as well as alternative rural routes. This study proposes that the data and information gathered will be incorporated onto a digital map of York to reveal collection locations and routes as well as pollution concentrations and compounds present within filter samples. Combining this data with photos and video snapshots of each performance ride will improve the public's ability to see for themselves pollution within their city. This interdisciplinary collaboration would also increase our understanding of environmental hazards facing cyclists and the benefits of a healthier environment through improved infrastructure. This study will help monitor and creatively disseminate exactly what cyclists and the public are exposed to and will help to inform effective solutions.

Despite ongoing evidence that suggests art enhances our understanding of science and data, there is still much to analyse regarding impact and personal realisation for action. This study provides initial evidence that the public engages with creative and visual outcomes that aim to make the invisible, visible. 
A laboratory perspective of extreme events in a global warming scenario
Authors: Harlander Uwe , Rodda Costanza , Vincze Miklos
Published: March 2022

Laboratory experiments are used to study the effect of Arctic warming on the amplitude and zonal phase speed of mid-latitude jet meanders. Our results show that a progressive decrease of the meridional temperature difference 1) slows down the eastward propagation of the jet stream, 2) complexifies its structure, and 3) increases the frequency of extreme events. Extreme events and temperature variability show a clear trend in relation to the Arctic warming only at latitudes influenced by the jet stream, whilst such trend reverses in the equatorial region south of the subtropical jet. Despite missing land-sea contrast in the laboratory model, we find similar trends of temperature variability and extreme events in the experimental data and the National Centers for Environmental Prediction (NCEP) reanalysis data. Moreover, our data qualitatively confirm the decrease in temperature variability due to the meridional temperature gradient weakening (which has been proposed recently based on proxy data). Probability distributions are weakly sensitive to changes in the temperature gradient, which is in accordance with recent findings from quasigeostrophic models. 
Short-term anthropogenic impact of mobile bottom-contact fishing on the biogeochemistry of coastal sediments and its long-term effects on mineral distribution
Authors: Roeser Patricia , Zeller Mary A. , Feldens Peter , Kallmeyer Jens , Clemens David , Rooze Jurjen , Radtke Hagen , Schönke Mischa , Schmiedinger Iris , Forster Stefan , Sommer Stefan , Böttcher Michael E.
Published: March 2022

The research project MGF-Ostsee deals with the consequences of the exclusion of mobile bottom-contact fishing in the southern Baltic Sea, specifically to assess its effects on the biogeochemistry of surface sediments and across the benthic-pelagic food chain. In Summer 2021, an in-situ monitored experiment was conducted at a coastal site in the region of Warnemünde/Rostock to investigate the short-term impacts of bottom trawling. Herein, we present first results on how this anthropogenic intervention affects biogeochemical processes and associated elemental cycling, as well as the resulting changes in geochemical mineral tracers. We analyzed porewater and sediment, as well as the water column for major, minor and trace elements, and the stable isotope composition (C, S, O) of dissolved and solid carbon and sulfur species. Porewater gradients are combined with lander-based oxygen-consumption- and radiotracer-based microbial sulfate reduction rates to elucidate how the disturbances by the fishing gear affect element (C, P, Mn, Fe, S) and mineral (re)distribution.

The controlled trawling experiment generated a re-suspension plume that reached up to 2 m above the sea floor, with 4 NTU in the lowermost portion. In the central trawled area, short cores were taken with a MUC prior and one to two hours after the experiment, and on the following day. In addition, sediment cores were recovered by divers from furrows and mounds of recent trawl marks. First results suggest that in the trawled area, the coupled Fe-Mn-P cycle reacts most sensitively, as expressed by altered porewater gradients and element diffusion. In the trawl marks, pore waters are affected differently whether sediments are removed, as in trawl furrows (erosion), or added/topped, as in trawl mounds (burial). In general, the tentative results point towards a Mn loss in the trawling area and in the furrows, whereas in the mounds Mn becomes enriched. The observed short-term changes in geochemical patterns from the experiment in the Warnemünde region are compared to data from a monitored region in the Fehmarn Belt. There, the observed patterns are tentatively associated to meso-scale areas with a history of low or high trawling impact.
Coincident glacier and lake evolution across New Zealand: Past, present, and future
Authors: Sutherland Jenna , Carrivick Jonathan , Huss Matthias , Purdie Heather , Stringer Christopher , Grimes Michael , James William , Shulmesiter James
Published: March 2022

Mountain glaciers are rapidly diminishing and causing widespread environmental and socio-economic concern. The stability of mountain glaciers is influenced by the expansion of proglacial landscapes and meltwater impounded as lakes within natural topographic depressions or ‘overdeepenings’. In particular, the relative sensitivity of mid-latitude glaciers to modern climate change makes them especially important to consider. One of the most striking features of South Island, New Zealand, is the sequence of glacial lakes that occupy mountain valleys along the Southern Alps. Our previous work has highlighted that the presence of these lakes is likely to have had an impact on ice-marginal dynamics of their adjacent glaciers, thereby influencing the rate of deglaciation on sub-millennial timescales. This emphasizes the need to incorporate proglacial lakes into palaeoglacier reconstructions and into analyses of future glacier evolution. In this new study we (i) document contemporary loss of glacier ice across the Southern Alps, (ii) analyse ice-marginal lake development since the 1980s, (iii) utilise modelled glacier ice thickness to suggest the position and size of future lakes, and (iv) employ a large-scale glacier evolution model to suggest the timing of future lake formation and future lake expansion rate. In recent decades, Southern Alps glaciers have fragmented both by separation of tributaries and by detachment of ablation zones. Glacier margins in contact with a proglacial lake have experienced the greatest terminus retreat. Our analysis indicates a positive relationship between mean glacier mass balance and rate of lake growth and with length of an ice-contact lake boundary. We project sustained and relatively homogenous glacier volume loss for east-draining basins but in contrast a heterogenous pattern of volume loss for west-draining basins. Our model results show that ice-marginal lakes will increase in number and combined size towards 2050 and then decrease to 2100 as glaciers disconnect from them. Overall, our findings should inform (i) glacier evolution models into which ice-marginal lake effects need incorporating, (ii) studies of rapid landscape evolution and especially of meltwater and sediment delivery, and (iii) considerations of future meltwater supply and water quality.
Joint inversion of Magnetotelluric Data and Surface-Wave Dispersion Curves using Correspondence Maps
Authors: Aquino Monica , Marquis Guy , Vergne Jerome
Published: March 2022

We use a correspondence map approach to jointly invert surface-wave dispersion curves and magnetotelluric data for subsurface shear velocity and resistivity but also for a possible relationship between them. Our first experiments consist of inversions of synthetic data computed from models linked by linear and second-order polynomial relationships. Our methodology produces joint inversion model-pairs (resistivity-shear velocity) from where 80% fit the 'observed' parameter relationship within a 5% error vs only 1%  of the separate inversion model-pairs for the linear relationship experiment. For the non-linear relationship synthetic test, 85% of the joint inversion model-pairs fit the 'observed' relationship within a 5% error while just 40% of the separate inversion model-pairs. This reduces the number of acceptable models without compromising the data fit ('reduction of non uniqueness'). Using the non-linear synthetic data we show how to select an appropriate polynomial degree for joint inversion. Having validated the approach with synthetic cases, we applied our methodology to field data from the ECOGI and EstOF surveys in North Alsace, France. We compare separate and joint inversions and we find that the 1D subsurface models obtained from joint inversions are more similar to previous models documented in the area than the separate inversion models. We are currently extending this work to higher dimensions. At the spatial scale of our problem, sensitivity analysis suggests that shear velocity models can benefit from the lateral sensitivity of the magnetotelluric data.
Can satellite images provide supervision for cloud systems characterization?
Authors: Chatterjee Dwaipayan , Deneke Hartwig , Crewell Susanne
Published: March 2022

With ever-increasing resolution, geostationary satellites are able to reveal the complex structure and organization of clouds. How cloud systems organize is important for the local climate and strongly connects to the Earth's response to warming through cloud system feedback.

Motivated by recent developments in computer vision for pattern analysis of uncurated images, our work aims to understand the organization of cloud systems based on high-resolution cloud optical depth images. We are exploiting the self-learning capability of a deep neural network to classify satellite images into different subgroups based on the distribution pattern of the cloud systems.

Unlike most studies, our neural network is trained over the central European domain, which is characterized by strong land surface type and topography variations. The satellite data is post-processed and retrieved at a higher spatio-temporal resolution (2 km, 5 min), enhanced by 66% compared to the current standard, equivalent to the future Meteosat third-generation satellite, which will be launched soon.

We show how recent advances in deep learning networks are used to understand clouds' physical properties in temporal and spatial scales. In a purely data-driven approach, we avoid the noise and bias obtained from human labeling, and with proper scalable techniques, it takes 0.86 ms and 2.13 ms to label an image at two different spatial configurations. We demonstrate explainable artificial intelligence (XAI), which helps gain trust for the neural network's performance.

To generalize the results, a thorough quantified evaluation is done on two spatial domains and two-pixel configurations (128x128, 64x64). We examine the uncertainty associated with distinct machine-detected cloud-pattern categories. For this, the learned features of the satellite images are extracted from the trained neural network and fed to an independent hierarchical - agglomerative algorithm. Therefore the work also explores the uncertainties associated with the automatic machine-detected patterns and how they vary with different cloud classification types.
Case study of interacting large-scale solar wind phenomena in the heliosphere
Authors: Geyer Paul , Dumbovic Mateja , Temmer Manuela
Published: March 2022

The interaction of interplanetary coronal mass ejections (ICMEs) and stream interaction regions (SIRs) gives rise to complex heliospheric plasma and magnetic field conditions. Considering the different magnetic configurations of both phenomena as well as the source regions in the solar corona, there is also the possibility of magnetic reconnection either at coronal heights or farther out in the heliosphere.

The event of February 7th, 2014 shows clear signatures of a qualitative alteration of the ICME structure in ACE plasma and magnetic field data. There is a significant drop of the magnetic field strength inside the FR simultaneously to an enhancement in temperature and a high variability of speed. The flow angle reversal expected to take place at the stream interface sharply coincides with the onset of the ICME magnetic field rotations and drop of temperature below expected temperature. The speed inside the flux rope, yet showing the aforementioned variations, overall features a decline from the front to the rear of the ICME. The launch site of the ICME is derived from SDO AIA data, showing its location to be 30° West from a N-S elongated coronal hole.

These results imply a deterioration of the FR due to magnetic reconnection, either caused by the proximity of CH and CME eruption site and favorable magnetic configurations, or the heliospheric interaction of the associated SIR and ICME. WSA-ENLIL simulations suggest that the ICME catches up with the SIR close to Earth, which, along with the in-situ signatures, implies the simultaneous occurrence of stream interface and flux rope onset. The declining speed profile that is characteristic for quiescent ICME spatial evolution suggests no high-speed stream is inhibiting expansion from behind. Due to its complexity, this event provides a great opportunity to study the interaction of ICMEs and SIRs.
Enzyme activity gradients across the maize roots
Authors: Ibrahim Zeeshan , Ghaderi Negar , Blagodatskaya Evgenia
Published: March 2022

The labile organic compounds provided by roots remove the nutrient limitation and thus stimulate microbial activity and facilitate biochemical process rates into the soil, forming microbial hotspots. However, the extent of root effect and the functional properties of microorganisms are dependent on the root morphology and can vary with the distance from the root. The objective of this study was 1) to investigate whether biochemical processes mediated by hydrolytic enzymes that are involved in C, N, and P cycling, are overlapping in the rhizosphere hotspots or whether they are hotspot-specific and 2) to evaluate the effect of plant genotype on the kinetic parameters in the hotspots. We identified the hotspots from two maize (Zea mays L.) plant genotypes (wild type and root hair deficient mutant) by applying zymography of β-glucosidase, acid phosphatase, and leucine aminopeptidase. Soil samples were taken at 1, 1-2, and >2mm from the hotspots epi-centrum.  The Vmax of β-glucosidase was 1.7 times higher at a 1mm distance from roots than 1-2mm and was 4 times higher than >2mm distance. The Vmax of β-glucosidase was significantly higher in the wild type versus root hair-deficient mutant at a 1mm distance from the root. Acid phosphatase and leucine aminopeptidase in both 96-well microplate and image processing indicated higher enzymes activity at the epi-centrum than outside the hotspot. In general, the microplate assay demonstrated similar trends with soil zymography, but the latter ensured better statistical significance. The Km values indicated similar enzyme systems within and outside the hotspots across the plant roots. The Km values suggested that root hair deficiency was compensated by higher affinity of enzymes acquiring C, N and P for the plant. In contrast, wild type of maize attracts microorganisms with broader spectrum of functional traits compared to root hair-deficient mutant. This work was conducted within the framework of the priority program 2089 “Rhizosphere spatiotemporal organization – a key to rhizosphere functions”, funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) – Project number: 403664478. Seeds of the maize were provided by Caroline Marcon and Frank Hochholdinger (University of Bonn).

Keywords: Zymorgaphy, Enzyme activity, Enzyme affinity
Impact of GPM Precipitation Error Characteristics on Hydrological Applications
Authors: Pradhan Ankita , Jayaluxmi Indu
Published: March 2022

Precipitation-measuring satellites constitute a constellation of microwave and infrared sensors in geosynchronous earth orbit. The limited sampling of passive microwave constellations continues to be a problem, affecting applications such as hydrological modeling. Recent constellations have contributed in the construction of the next generation of earth and space science missions by allowing measurement settings to be customized to meet changing scientific understanding. Our study focuses on examining the Global Precipitation Measurement (GPM) constellation mission. The aim of the study is to examine the impact of different uncertainties carried by the GPM constellation on hydrological applications. Firstly we investigated the evaluation and comparison of spatial sampling error for the Global Precipitation Measurement (GPM) mission orbital data products. The region over India with high seasonal rainfall appears to have lower sampling uncertainty, and vice versa, with some exceptions due to differences in precipitation variability and space-time correlation length.  Second, we investigated how intermittency produced by low temporal sampling propagates through a hydrological model and contributes to stream flow uncertainty. We also examined the effect of grid resolution and how it relates to Clausius-Clapeyron scaling. This paper proposes and discusses techniques for quantifying the influence of grid resolution as a function of spatial–temporal characteristics of heavy precipitation based on these findings. Thirdly, we have quantified the influence of two different algorithms i.e top down and bottom up approach utilizing precipitation products that includes the Global Precipitation Measurement mission's (GPM) integrated Multi-satellite Retrievals (IMERG) late run, the SM2RAIN-Climate Change Initiative (SM2RAIN-CCI), and the SM2RAIN-Advanced SCATerometer (SM2RAIN-ASCAT) on hydrological simulations. The results from our study indicate that precipitation forcing at 6-hourly integration outperforms the stream flow simulations as compared to 3-hourly and 12-hourly forcing integration times. IMERG based precipitation also contains significant bias which is propagated into hydrological models when used as precipitation forcing.
Nonlinearity and asymmetry in the atmospheric branch of ENSO with a simple GCM
Authors: Beniche Margot , Hall Nicholas , Vialard Jérôme , Lengaigne Matthieu
Published: March 2022

We assess dynamical nonlinearities and asymmetries in the atmospheric branch of the Bjerkness feedback. The atmospheric response to El Nino-related sea surface temperature anomalies (SSTAs), consists of developing deep convection with low-level westerlies west of the anomalous heating. Simple models of ENSO usually assume this process to be linear and symmetric. In this study, we use a global primitive equation model to evaluate nonlinearities and asymmetries that can potentially modify the Bjerkness mechanism.

The Dynamical Research Empirical Atmospheric Model (DREAM) is a global primitive equation model. It explicitly calculates advection and linear diffusion but physical processes are represented by an external empirical forcing deduced from ERA-Interim data. DREAM can be used as a stationary wave model where a perturbation develops on a fixed basic state. Both linear and nonlinear perturbations can be simulated by controlling the amplitude of the anomaly. DREAM can also be used as a simple GCM. In this case the model develops transient eddy fluxes and we obtain a full nonlinear solution. ENSO perturbations are introduced as a deep convective heating based on precipitation anomalies. Both idealised and realistic heating anomalies are studied, deduced from observed precipitation composites or calculated from SSTAs using an empirical transfer function.

The linear response to equatorial heating is strongly dependent on the position of the heating. Stationary equilibrium responses to idealised equatorial heating show that the response to a source in the East Pacific is larger than for the West Pacific. Stationary wave solutions are weakly nonlinear in heating amplitude, and the modification of the linear response is well explained as a linear response to stationary nonlinear fluxes. In fully turbulent simple GCM experiments, the response to equal and opposite heating perturbation shows a much larger asymmetry. This is diagnosed in terms of the linear response to anomalous transient eddy fluxes. The degree of nonlinearity in the response depends on the region and the variable under consideration. Nonlinearity is strong in the extratropics but less likely to be a significant factor locally and so probably of secondary importance for the Bjerkness feedback. However, the sensitivity of the response to diverse and asymmetric perturbation forcing implies that even when nonlinearity is weak, the asymmetric nature of the atmospheric response must be taken into account.
Tectonic Characteristics and Controls on Hydrocarbon Accumulation in Middle Section of Western Sichuan Depression
Authors: Wang Xinpeng , Chen Shuping , Zhang Chi , Li Wenyong
Published: March 2022

Western Sichuan Depression is located in the west of the Sichuan Basin and has shown great gas prospects for many years. Due to the characteristics of multiple stages of tectonic evolution and multiple directions of tectonic distribution, petroleum geological conditions are extremely complex in this area. In this paper, we use geological data, seismic data, well logging, and petroleum geological data to study the tectonic characteristics and controls on hydrocarbon accumulation in the middle section of the Western Sichuan Depression. The middle part of the Western Sichuan Depression is dominated by thrust structures, including thrust structures formed by the combination of thrust faults, fault triangular belt, and thrust imbricate structures, as well as fold deformation related to thrust faults, such as snake-head structure and slippage fold. The study area is characterized by east-west zonation and up-down stratification. In the process of formation and evolution, Western Sichuan Foreland Basin mainly experienced three tectonic periods, namely the Indosinian period, the Yanshan period, and the Himalayan period. Multi-stage tectonics, the change of force source, and principal stress direction also lead to the formation of tectonic series and tectonic belts with different trends. Most of the traps of the Leikoupo Formation in the region had their embryonic form in the late Indochinese period, which was further developed in the Yanshanian period, and basically formed in the early Himalayan period. Therefore, the tectonic conditions and accumulation conditions were well arranged, forming self-generation and self-accumulation or a combination of self-generation and self-accumulation and up-generation and sub-accumulation reservoir formation mode. The superior accumulation conditions and tectonic conditions make the Marine strata of the Leikoupo Formation of the Western Sichuan Depression show more favorable exploration potential. This study reveals structural style of the piedmont belt in the foreland basin and establishes reliable evidences for the further development of regional structural and accumulation models, which are crucial for further oil and gas explorations.
Interannual variability in Sargassum seaweed transport from the Sargasso Sea to the equatorial Atlantic and Caribbean Sea
Authors: Durston Sophie , Holt Jason , Wolf Judith , Gommenginger Christine , Grosvenor Dan , Lavender Samantha
Published: March 2022

Since 2011, Caribbean beaches have been regularly swamped by large quantities of a floating seaweed called Sargassum. Blooms of Sargasssum form large mats in the equatorial Atlantic and at their peak can span from the Gulf of Mexico to west coast of Africa, forming the Great Atlantic Sargassum Belt (GASB). Sargassum beaching events have significant environmental and socio-economic impacts, including impacts on fisheries, tourism, nesting marine animals, and coral reefs. Prior to 2011, Sargassum was predominantly found entrained within the currents of the North Atlantic Subtropical Gyre in the Sargasso Sea. It is thought that an extreme negative phase of the North Atlantic Oscillation (NAO) in 2010/2011 may have produced conditions in the Sargasso Sea that allowed Sargassum to escape and populate further south. The NAO impacts the strength and direction of winds over the Atlantic and modulates ocean properties such as sea surface temperature (SST) and mixed layer depth. Could a change in wind and ocean circulation in 2010 and 2011 explain how Sargassum escaped the ocean gyre as an extreme one-off event? In this study, Lagrangian particle tracking simulations are used to investigate the likelihood of Sargassum leaving the Sargasso Sea between 2009 and 2021, using a velocity field from the Copernicus Marine Environment Monitoring Service (CMEMS) GLORYS12V1 reanalysis. The study’s results show interannual variability in the escape of particles eastwards from the Sargasso Sea into the equatorial Atlantic and Caribbean Sea.
Ecosystem multifunctionality of forest patches in the tropics: A systematic literature review
Authors: Tabi Eckebil Paule Pamela , Wingate Vladimir Ruslan , Akinyemi Felicia Olufunmalayo , Ifejika Speranza Chinwe
Published: March 2022

The ability of forests to provide multiple ecosystem functions and services including Nature’s Contributions to People is a key concern for achieving their sustainability. The multifunctionality of an ecosystem is its ability to maintain multiple functions simultaneously. The concept of ecosystem multifunctionality has been defined broadly in various studies to measure the abiotic and biotic functions of ecosystems including their contributions to ecosystems services. However, applications of multifunctionality to fragmented forests remain limited, particularly in the case of tropical forest patches. This review synthesizes the current knowledge on ecosystem multifunctionality of forest patches in the tropics. Moreover, it explores the key factors that affect the multifunctionality of forest patches and the trade-offs to consider. The presented analysis and results will highlight the multiple functions of tropical forest patches, and will explore particular contexts such as forest patches in agricultural landscapes in West Africa and contrast with other tropical regions. The findings can inform stakeholders on the valuation of ecosystems multifunctionality related to tropical forest patches and their contributions to human wellbeing.

KEYWORDS: Ecosystem multifunctionality, Ecosystems services, Nature’s Contributions to People, Multifunctional landscape, Forests patches, Tropics, West Africa.
Satellite Remote Sensing Investigation of 21 July 2020 Shaziba Landslide, China
Authors: Wang Wandi , Motagh Mahdi , Mirzaee Sara , Roessner Sigrid , Li Tao
Published: March 2022

Satellite Remote Sensing Investigation of 21 July 2020 Shaziba Landslide, China

 

Wandi Wang1,2, Mahdi Motagh1,2, Sara Mirzaee3, Sigrid Roessner1 and Tao Li4

Section 1.4 - Remote Sensing and Geoinformatics, GFZ German Research Center for Geosciences, Potsdam, Germany

Institute of Photogrammetry and Geoinformation, Leibniz University Hannover, Hannover, Germany

Department of Marine Geology and Geophysics, University of Miami, United States

GNSS Research Center, Wuhan University, China

 

We present the results of remote sensing analysis of deformation related to the 21 July 2020 Shaziba landslide in China. The landslide, which occurred following the heavy precipitation from June to August 2020, is located at the Qingjiang River, approx. 30 km from Enshi City in Hubei Province of China.   It destroyed over 60 houses, and by blocking the course of the river, formed a landslide dam, which threatened the safety of people and infrastructure downstream. Although Shaziba landslide occurred in form of reactivation of an old landslide, the landslide prone slope was not instrumented prior to this most recent failure. Therefore, high-resolution remote sensing imagery was used as a very effective source of information for a detailed investigation of the evolution of this slope failure.  We collected the satellite remote sensing data covering a time period from June 2016 to July 2021 and comprise optical and radar data. Firstly, cross-correlation analysis using satellite optical imagery from Planet and Sentinel-2 systems was used to retrieve the lateral direction and magnitude of landslide movements. Next, multi-temporal interferometry (MTI) analysis based on Sentinel-1 and TerraSAR-X SAR data was exploited to obtain pre- and post-failure deformation. Results from different MTI techniques including Persistent Scatterer (PS), Small Baseline Subsets (SBAS), and Eigendecomposition based Maximum-likelihood-estimator of Interferometric phase (EMI) were compared to evaluate the most suitable method for InSAR time-series analysis of deformation related to the evolution of Shaziba landslide. Finally, several high-resolution DEMs derived from TanDEM-X (TDX) data were analyzed using repeat-pass interferometry and stacked together to compensate for the errors related to DEM alignment in order to precisely estimate the landslide volume. The results highlight how the integration of various remote sensing sensors helps to gain a better understanding of landslide evolution process and characterization. 
Life in undies – Preliminary results of a citizen science data collection targeting soil health assessement in Hungary
Authors: Árvai Mátyás , László Péter , Takáts Tünde , Kovács Zsófia Adrienn , Takács Kata , Mészaros János , Pásztor László
Published: March 2022

Last year, the Institute for Soil Sciences, Centre for Agricultural Research launched Hungary's first citizen science project with the aim to obtain information on the biological activity of soils using a simple estimation procedure. With the help of social media, the reactions on the call for applications were received from nearly 2000 locations. 

In the Hungarian version of the international Soil your Undies programme, standardized cotton underwear was posted to the participants with a step-by-step tutorial, who buried their underwear for about 60 days, from mid of May until July in 2021, at a depth of about 20-25 cm. After the excavation, the participants took one digital image of the underwear and recorded the geographical coordinates, which were  uploaded to a GoogleForms interface together with several basic information related to the location and the user (type of cultivation, demographic data etc.).

By analysing digital photos of the excavated undies made by volunteers, we obtained information on the level to which cotton material had decomposed in certain areas and under different types of cultivation. Around 40% of the participants buried the underwear in garden, 21% in grassland, 15% in orchard, 12% in arable land, 5% in vineyard and 4% in forest (for 3% no landuse data was provided).

The images were first processed using Fococlipping and Photoroom softwares for background removing and then percentage of cotton material remaining was estimated based on the pixels by using R Studio ‘raster package’.

The countrywide collected biological activity data from nearly 1200 sites were statistically evaluated by spatially aggregating the data both for physiographical and administrative units. The results have been published on various platforms (Facebook, Instagram, specific web site etc.), and a feedback is also given directly to the volunteers.

According to the experiments the first citizen science programme proved to be successful. 

 

Acknowledgment: Our research was supported by the Hungarian National Research, Development and Innovation Office (NKFIH; K-131820)

Keywords: citizen science; soil life; soil health; biological activity; soil properties
Detecting natural and anthropic effects on displacements and water level changes: a combined observation from rain gauges, piezometers and CGNSS
Authors: Nespoli Massimo , Cenni Nicola , Belardinelli Maria Elina , Marcaccio Marco
Published: March 2022

The Po Plain (Northern Italy) has largely subsided due to natural processes and human activities. In particular, in order to reduce subsidence, in the Bologna metropolitan area a politic decision in 2010, imposed a significant reduction of civil water supply from groundwater withdrawal wells. The study area is characterized by an excellent monitoring activity which provides a good spatial and temporal distribution of data coming from continuous GNSS sites, piezometers and rain gauges.

In the present work we analyze both GNSS and piezometric data by means of the Principal Component Analysis (PCA). The results of the analysis are then compared with the rainfall time series measured by rain gauges. Thanks to the PCA analysis we can identify: i) a clear increase in the water level following the withdrawal decrease started in 2010 and ii) an anthropic induced surface displacement, which is smaller in magnitude than that induced by rainfall variations. Without the PCA analysis, such a small, but still significant, anthropic effect on vertical displacements would have remained hidden in the raw time series.

Our analysis reveals a decrease of about 4 mm/y of vertical velocity in some GNSS sites closest the withdrawal wells. We also found that on large time scales (> 1 month), the vertical displacement induced by rainfall strongly depends on the geological setting: in the mountains a water level increase causes subsidence (elastic response), whereas in the Po Plain it causes uplift (poro-elastic response). Thanks to the PCA analyses, the combined observations of different kind of instruments (GNSS, piezometers and rain gauges) and a basic knowledge of the geological context, we can correctly identify both the anthropic and natural signals on the data.
DSM with covariates at different resolution for Mongolia 
Authors: Genova Giulio , Poggio Laura , Kempen Bas , Baatar Undrakh-Od , Sarangerel Enkhmaa , Ganbold Uganbat
Published: March 2022

Digital Soil Mapping (DSM) is an established methodology to create maps of soil properties at different resolutions and extents. It establishes a statistical relationship between the measured values at point observations and environmental covariates selected to describe the soil forming factors and to explain the spatial variability of the soil properties. These relationships are then used to map the target soil properties across the area of interest. In this example, we used 1423 measurements on soil organic carbon and pH for the 0-20 cm soil layer from a Mongolian soil survey. This survey was organised within the framework of the “National Program to Combat Desertification” to determine the primary soil quality indicators for desertification assessment in Mongolia and it was conducted based on the state network of the Meteorological and Environmental Research Agency starting in 2012. The samples are collected from 1500 monitoring points every 5 years. We used data from the monitoring round between 2012 and 2015 We used two sets of covariates for modelling predictive relationships. The first is the set used in SoilGrids at 250 m resolution with over 400 layers available of which about 180 were used for the modelling, after de-correlation. The second is a reduced set of about 40 covariates at 100 m resolution derived mainly from Sentinel (1 and 2) images, ERA5 for climate data and ALOS for morphological information.  In this study we will compare the results of the two models, with both point-wise evaluation matrices and assessment of spatial patterns. In the evaluation the expertise of local partners will also be used. 