bluuebunny/crossref_metadata_2025 huggingface dataset:
The impact of assimilating Earth Observation and in situ data on seasonal hydrological predictions in a snow-dominated river system
Authors: Musuuza Jude Lubega , Crochemore Louise , Pechlivanidis Ilias G.
Published: March 2022

Earth Observations (EO) have become popular in hydrology because they provide valuable information in locations where direct measurements are either unavailable or prohibitively expensive to make. Recent scientific advances have enabled the assimilation of EO’s into hydrological models to improve the estimation of initial states and fluxes which further leads to improved forecasting of different hydrometeorological variables. When assimilated, the data exert additional controls on the quality of the forecasts; it is hence important to apportion the effects according to model forcing and the assimilated data. Here, we investigate the impact of assimilating different EO and in itu data-sets individually and as combinations on the discharge and reservoir inflow estimations in the snow dominated Umeälven catchment in northern Sweden. We further assess the impact of the assimilations on seasonal predictions over the catchment. Six datasets are assimilated comprising of four EO products (fractional snow cover, snow water equivalent, and the actual and potential evapotranspiration) and two in situ datasets (discharge and reservoir inflow). For the latter investigation,  we drive the E-HYPE hydrological model with two meteorological forcings: (i) a down-scaled GCM product based on the bias-adjusted ECMWF SEAS5 seasonal forecasts, and (ii) historical meteorological data based on the Ensemble Streamflow Prediction (ESP) method. We finally assess the impacts of the meteorological forcing and the assimilated data on the streamflow and reservoir inflow seasonal forecasting skill for the period 2001-2015. We assessed the value of assimilating different data-sets and identified the datasets that can be meaningfully combined. We further show that all assimilations generally improve the forecasting skill but the improvement varies depending on the season and assimilated variable. The lead times until when the data assimilations influence the forecast quality are also different for different datasets and seasons; as an example, the impact from assimilating snow water equivalent persists for more than 20 weeks during the winter. We finally show that the assimilated datasets exert more control on the forecasting skill than the meteorological forcing, highlighting the importance of initial hydrological conditions for this snow-dominated river system.
Evidence of a complex structure within the 2013 August 19 coronal mass ejection. Radial and longitudinal evolution in the inner heliosphere
Authors: Rodríguez-García Laura , Nieves-Chinchilla Teresa , Gómez-Herrero Raúl , Zouganelis Ioannis , Vourlidas Angelos , Balmaceda Laura , Dumbovic Mateja , Jian Lan , Mays Leila , Carcaboso Fernando , Guedes-Dos Santos Luiz Fernando , Rodríguez-Pacheco Javier
Published: March 2022

Context. Late on 2013 August 19, a coronal mass ejection (CME) erupted from an active region located near the far-side central meridian from Earth’s perspective. The event and its accompanying shock were remotely observed by the STEREO-A, STEREO-B and SOHO spacecraft. The interplanetary (IP) counterpart (ICME) was intercepted by MESSENGER near 0.3 au, and by both STEREO-A and STEREO-B, near 1 au, which were separated by 78 degrees in heliolongitude.

Aims. The main objective of this study is to follow the radial and longitudinal evolution of the ICME throughout the inner heliosphere, and to examine possible scenarios for the different magnetic flux-rope (MFR) configuration observed on the solar disk, and measured in-situ at the locations of MESSENGER and STEREO-A, separated by 15 degrees in heliolongitude, and at STEREO-B, which detected the ICME flank.

Methods. Solar disk observations are used to estimate the ‘MFR type’, namely, the magnetic helicity, axis orientation and axial magnetic field direction of the MFR. The graduated cylindrical shell model is used to reconstruct the CME in the corona. The analysis of in-situ data, specifically, plasma and magnetic field, is used to estimate the global IP shock geometry and to derive the MFR type at different in-situ locations, which is compared to the type estimated from solar disk observations. The elliptical cylindrical analytical model is used for the in-situ MFR reconstruction.

Results. Based on the CME geometry and on the spacecraft configuration, we find that the MFR structure detected at STEREO-B belongs to the same ICME detected at MESSENGER and STEREO-A. The opposite helicity deduced at STEREO-B, might be due to the spacecraft intercepting one of the legs of the structure far from the MFR axis, while STEREO-A and MESSENGER are crossing through the core of the MFR. The different MFR orientations measured at MESSENGER and STEREO-A arise probably because the two spacecraft measure a curved, highly distorted and rather complex MFR topology. The ICME may have suffered additional distortion in its evolution in the inner heliosphere, such as the west flank is traveling faster than the east flank when arriving near 1 au.
Effect of soil microorganisms on organic carbon sequestrationindifferent soil landscapes of the Ouargla’s basin
Authors: Bensayah Maria Nour El Houda , Karabi Mokhtar , Hamdi Aissa Baelhadj , Berkal Ismaiel
Published: March 2022

The objective of this work is to study the effect of microorganisms on carbon sequestration in
different soil landscapes of Ouargla’s basin. Ouargla is part of the arid zones of the Algerian
Sahara, which is characterized by high temperatures, low and irregular precipitation, sparse
vegetation and soils poor in organic matter. However, the soil remains a favorable environment
for macros and microorganisms which tolerates this deficit. The soil provides ecosystem services
to these environments by protecting natural resources. Microbial biomass, which represents on
average 2 to 4% of organic carbon, is involved in renewing organic matter in the soil. For this
study, 7 stations of different pedo- sequences were chosen. After collection, the samples
underwent microbiological analyzes for enumeration of bacteria and fungi, fumigation-extraction
and physicochemical analyzes. The enumeration of the main microbial groups in bacteria and
fungi showed the predominance of bacterial microflora, followed by fungal microflora at higher
values in cultivated soil and those of Sebkhat. The identification of fungal species according to the
determination keys allowed us to identify the following species: Alternaria alternata, Rizopus sp
and Aspergillus niger, as well as yeasts. The microbial carbon values show that this parameter is
higher in Sebkhat N’Goussa, gypsum soil in Frane and in cultivated soil. These are the stations
where high values of organic carbon and organic matter are recorded. We can say that
microorganisms play an important role in carbon sequestration. They mineralize microbial
residues and provide carbon to the stable organic matter fraction of the soil. 

 

Key words: carbon sequestration, ecosystem service, microbial carbon, organic carbon, Ouargla.
The climate impacts of an abrupt AMOC weakening on the European winters 
Authors: Bellomo Katinka , Meccia Virna , D'Agostino Roberta , Fabiano Federico , von Hardenberg Jost , Corti Susanna
Published: March 2022

The Atlantic Meridional Overturning Circulation (AMOC) is thought to exist in multiple states of equilibria. In the present climate, the AMOC is believed to be in a relatively strong state, bringing warm waters into the North Atlantic and contributing to mild winters over Europe. However, proxy data show evidence of abrupt declines in the strength of the AMOC, often associated with the initiation of ice ages. The abrupt shifts in the strength of the AMOC are usually referred to as ‘tipping points’. Presently, state-of-the-art climate models are unable to spontaneously reproduce tipping points in the AMOC, preventing an accurate study of the climate impacts of an abrupt AMOC shutdown. Contextually, although it is deemed unlikely that the AMOC will collapse in response to climate change, it is expected to further slow down into the 21st century. The impacts of this weakening, relative to those of global warming, are poorly understood, especially on daily timescales.

            To address this question, we run water hosing experiments with the EC-Earth3 earth system model to investigate the impacts of an AMOC abrupt weakening on the winter climate variability focusing on the North Atlantic and Europe. We confirm results from previous studies showing a large decrease in temperature, precipitation, and an increase in the jet stream over Europe. However, we further investigate the moisture budget and the impacts on daily weather regimes and blocking. In contrast to previous hypotheses, we find that the reduction in precipitation over Europe is due to changes in the storm tracks rather than thermodynamic effects. Further, we find a significant increase in the frequency and persistence of NAO+ days. Finally, we show precipitation and temperature extremes that are expected in response to the AMOC weakening.

            Our results show the climate impacts on weather events that can be expected from an AMOC weakening alone, and are relevant to understanding the relative roles of greenhouse gas forcing and AMOC weakening on the European climate in simulations of future climate change.
Geological hazard assessment of volcanic islands: Insights from seafloor geomorphology and turbidites in sediment cores, central Azores Islands
Authors: Chang Yu-Chun , Mitchell Neil , Quartau Rui , Hansteen Thor , Schindlbeck-Belo Julie , Freundt Armin
Published: March 2022

Volcanic eruptions and submarine landslides and may have occurred frequently among the central Azores (Faial, Pico, São Jorge, and Terceira islands) because landslide valleys are abundant on their submarine slopes and dark volcaniclastic beds are common in sediment cores. The threats of future such processes need evaluating for citizens living on the islands. A multidisciplinary approach was applied to provide a hazard assessment based on high-resolution multibeam bathymetric data and four gravity cores collected in basins amongst the islands.

More than 1200 submarine slope valleys were documented from the bathymetric data. Based on their morphological features, >300 of them were interpreted to be likely of landslide origin and produced by single slope failures. Thirteen of them would probably have generated tsunamis with heights at source 1-7 m. This may explain some tsunamis recorded in the area that cannot be assigned to earthquakes. Different landslide abundances and mean volumes were also found between two groups of islands. There are more and smaller landslides in one group (Faial and Pico) compared with fewer but larger landslides around another group (São Jorge and Terceira). This may be explained by a more frequent triggering of slope failure around Faial and Pico, which prevent the accumulation of thick superficial deposits, or sediment densification by ground shaking. This may suggest a greater threat from large earthquakes among these two islands that is not currently found in earthquake records.

The sediment cores were analyzed to interpret whether emplacements of volcaniclastic beds were from tephra fallout, pyroclastic flows or submarine landsliding. This required assessing various information, including sedimentary structures, glass shard geochemistry and morphometrics, bulk composition and organic geochemistry. From the results, 2/3 of the volcaniclastic beds originated directly from erupting volcanoes, whereas only 1/3 involved slope remobilization such as landsliding. The modal thickness of the volcaniclastic beds is small (2-20 cm). The low incidence of beds of landslide origin could be explained either by landslide-generated sediment flows infrequently reaching the basin floors and/or eruptions creating beds more frequently. Based on 14C datings, all types of turbidity currents have reached the core sites at a modest frequency since the Last Glacial Maximum (0.45 events/kyr on average).
Are Pi2 pulsations in meridian plane a field line dipolarization?
Authors: Saka Osuke , Klimushkin Dmitri
Published: March 2022

Dawn-dusk flow shears in the nightside magnetosphere associated with field line dipolarization produce tangential discontinuities in the midnight sector and generate periodic displacement of the discontinuity surface at Pi2 periodicities through the KH instabilities [Saka et al., 2010].

Wave polarizations of Pi2 pulsations thus produced in the magnetosphere by the boundary displacement are generally reversed in the polar ionosphere [Saka et al., 2012]. The polarization reversal cannot be understood through the reconfiguration of geomagnetic field lines in terms of the fundamental harmonics but rather by considering the third harmonics in the meridian planes. On the ground, negative bays marked by decrease of the northward component of the geomagnetic fields are observed. We show that the field line deformations associated with third harmonics matched those of field line dipolarization and they are produced by the poloidal wave mode guided along the field lines: guided poloidal mode [Radoski, 1967]. This result indicates that Pi2 pulsations in meridian plane are field line dipolarization itself excited at the outer boundary of closed magnetosphere.

 

References

Radoski, H., Highly asymmetric MHD resonances: the guided poloidal mode, J. Geophys. Res., 72, 4026, 1967.

Saka,O., Hayashi, K., and Thomsen, M., First 10 min intervals of Pi2 onset at geosynchronous altitudes during the expansion of energetic ion regions in the nighttime sector, J. Atmos. Solar Terr. Phys., 72, 1100, 2010.

Saka, O., K. Hayashi, and D. Koga, Excitation of the third harmonic mode in meridian planes for Pi2 in the auroral zone. J. Geophys. Res., 117, A12215, doi:10.1029/2012JA018003, 2012.
An experimental approach for developing a building damage matrix for the flood-affected vernacular housing typology
Authors: Narendr Aishwarya , Anand Shantanu , Haridas Aithal Bharath , Das Sutapa
Published: March 2022

The study aims to investigate flood-related damage on earthen buildings using an experimental analysis. Wattle and daub method is the main construction technique used in the coastal part of West Bengal, India. Housing damage caused due to floods is often poorly compensated due to the absence of an established loss-assessment scale for vernacular housing typologies a predominant construction practice in the study region. Earthen buildings developed using various techniques have proven functional, while offering multiple benefits such as cost and energy efficiency along with thermal comfort. Despite the benefits, the functionality gets significantly reduced due to their susceptibility to flooding instances that are likely to increase with aggravating extremes as a result of changing climate. The contribution of vernacular or traditional construction techniques if integrated with disaster resilience techniques shall prove indispensable in reducing the shortage of 29.6 million dwelling units for the low-income rural households by the year 2022 in the study region.

The qualitative assessment of the damage process involves visual inspection of the sealed model of the building component behaviour and a non-destructive test. Under the qualitative process, the sample is tested under Universal Testing Machine (UTM) machine to understand the loss of compressive strength at each stage of flooding. The process will result in a damaged matrix which is an array of loss percent for various depth–duration combinations. The matrix will help in identifying corresponding flood losses and deciding repair costs for varying flood intensity. In addition to this, the process can be identified as an imperative step while suggesting an alternate construction technique in such a flood-affected region.

Keywords: Flood damage,Vernacular housing, Damage matrix, Non-destructive tests, Destructive tests
A novel Zirconium-modified Coal Gasification Coarse Slag for phosphate adsorption
Authors: Yang Baoguo , Li Yilian
Published: March 2022

The excess phosphate in water leads to eutrophication, and hence finding cost effective adsorbing material for removing phosphorus from water is of great significance. Meanwhile, Coal Gasification Coarse Slag (CGCS) as a general solid waste, poses a potential threat to the environment. To solve these problems, herein, a novel low cost and high-efficiency adsorbing material was synthesized from CGCS by a facile method. The (CGCS)/ZrOCl2⋅8H2O mass ratio of 5:4 (denoted as CGCS-Zr4) was selected from a series of adsorbents with different mass ratios for subsequent sorption researches. The performance for phosphorus removal and related adsorption mechanism were investigated. The results showed CGCS-Zr4 had good adsorption property within a broad pH range. The Langmuir isothermal model, the pseudo-second-order kinetic and intra-particle diffusion model described the experiment data well, indicating that 1) the reaction process was monolayer and chemical adsorption; 2) rate determining step were both boundary layer effect and intraparticle diffusion. The adsorption mechanism of phosphorus on CGCS-Zr3 could be mainly achieved by electrostatic attractions and coordination reactions, forming inner-sphere phosphate complexes. The experiment results suggest that using Coal Gasification Slag (CGS) for removing phosphate could be a promising method in the wastewater treatment and resource utilization of solid waste.
Inferring soils' heterogeneous structure via hydro-electrical measurements at altering spatial scales  
Authors: Moreno Ziv
Published: March 2022

Understanding and predicting water flow and solute transport at the subsurface are important for agronomical, hydrological, and environmental applications. Nevertheless, due to the heterogeneous nature of soils, those predictions are subject to significant uncertainties. Although stochastic approaches have been proposed to cope with soil heterogeneity, uncertainties in model predictions remain high due to data scarcity and lack of spatially continuous measurements. Geo-electrical methods have the potential to significantly reduce models' uncertainties due to their ability to provide continuous, extensive, and non-invasive information of the subsurface. At the core of these methods, the obtained subsurface's electrical conductivity can be translated to hydrological state-variables via site-specific hydro-electrical relations calibrated with lab or field data. However, due to soil's heterogeneity, the hydro-electrical relations can be scale-dependent.

This work studied the impact of soil's heterogeneity at the sub-core level on the effective hydro-electrical relations scale dependency. For that purpose, synthetic soil samples with various geostatistical parameters were generated. Constant capillary pressure was applied, and water saturation maps were obtained using a van-Genuchten model and the Leverett J-function for retention and retention scaling. The water saturation maps were transformed to soil's electrical conductivity by adopting Archie's law with assumed "intrinsic" parameters. An electrical current was injected, and the corresponding electric potential was calculated. The soil's effective electrical conductivities at different spatial scales were estimated, and new effective hydro-electrical relations were calibrated for each measurement scale.

This forward approach had shown that each soil structure has a unique signature on the effective hydro-electrical relations calibrated at different measurement scales. Following those observations, a novel stochastic inversion technique, based on an iterative Bayesian approach and Markov Chain Monte Carlo sampling, was used to confine the soil's geostatistical properties. The proposed inversion technique was tested on three different scenarios: two synthetic cases with a known structure, and one real data case based on CT images of a two-phase CO2 and brine injection at altering fractional flows. Results have shown that the proposed approach was capable of confining the soil's geostatistical parameters with high accuracy and a narrow distribution around the actual values that were tested, by calibrating the effective hydro-electrical properties at only three different measurements scales.
Thallium and lead variations in a contaminated peatland: An isotopic study from a mining/smelting area
Authors: Vanek Ales , Vejvodova Katerina , Mihaljevic Martin , Ettler Vojtech , Penizek Vit , Trubac Jakub , Sutkowska Katarzyna , Teper Leslaw , Golias Viktor , Vankova Maria
Published: March 2022

Vertical profiles of Tl, Pb and Zn concentrations and Tl and Pb isotopic ratios in a contaminated peatland/fen (Wolbrom, Poland) were studied to address questions regarding (i) potential long-term immobility of Tl in a peat profile, and (ii) a possible link in Tl isotopic signatures between a Tl source and a peat sample. Both prerequisites are required for using peatlands as archives of atmospheric Tl deposition and Tl isotopic ratios as a source proxy. We demonstrate that Tl is an immobile element in peat with a conservative pattern synonymous to that of Pb, and in contrast to Zn. However, the peat Tl record was more affected by geogenic source(s), as inferred from the calculated element enrichments. The finding further implies that Tl was largely absent from the pre-industrial emissions (>~250 years BP). The measured variations in Tl isotopic ratios in respective peat samples suggest a consistency with anthropogenic Tl (ε205Tl between ~ -3 and −4), as well as with background Tl isotopic values in the study area (ε205Tl between ~0 and −1), in line with detected 206Pb/207Pb ratios (1.16–1.19). Therefore, we propose that peatlands can be used for monitoring trends in Tl deposition and that Tl isotopic ratios can serve to distinguish its origin(s). However, given that the studied fen has a particularly complicated geochemistry (attributed to significant environmental changes in its history), it seems that ombrotrophic peatlands could be better suited for this type of Tl research.
The influence of Coriolis force on sedimentation of the Yellow River
Authors: Liu Kejing , Liu Dawei
Published: March 2022

In the northern hemisphere, river subjects the right bank to the pressure generated by the Coriolis force, which will increase the erosion of the river on the right bank. On the other hand, the Coriolis force also causes the sediments in the water to move to the right bank, which will increase the sediment deposition on the right bank of the river. Therefore, for rivers with low sediment content, Coriolis force will increase the erosion of river water on the right bank; for rivers with high sediment content, Coriolis force will increase the sedimentation of sediment on the right bank. It is noted that the Lanzhou section of the Yellow River has siltation of sands and pebbles to the right (south) bank. It is believed that this is caused by the Coriolis force moving the sands and pebbles to the right bank.
Soil structure turnover under grassland is mainly driven by biotic drivers
Authors: Leuther Frederic , Mikutta Robert , Wolff Maximilian , Kaiser Klaus , Schlüter Steffen
Published: March 2022

Soil structure is a dynamic property of soils which undergoes continuous changes due to various abiotic and biotic drivers. At the same time, the spatial arrangement of pores, organic matter and minerals influences soil functions, such as storage and filtering of water, nutrient cycling, or habitat for soil organisms and plants. In terms of carbon storage and matter turnover, the rearrangement of soil structure and herewith the change in accessibility of soil carbon for microbial decomposition is highly relevant. However, the turnover of soil structure and its constituents is difficult to quantify. In this study, a new method of structure labelling with inert garnet-particles in combination with X-ray µCT was used to determine the turnover rate of macro-aggregates and their drivers in two field experiments. Trials were conducted in topsoils of a Chernozem and a Luvisol under grassland, both with a silty loam texture but under different climatic conditions (Chernozem = 480 mm precipitation, Luvisol 886 mm). Over the course of 4 years, soil structure was regularly determined by X-ray µCT at two resolutions, 60 µm and 15 µm, to track soil structure development with time and in response to seasons. By excluding roots and soil fauna > 30 µm in half of the samples, it was possible to estimate the contribution of abiotic and biotic drivers. The distribution of garnet particles was determined in order to quantify the rate of soil structure turnover as related to potential biotic drivers. It is shown that soil structure turnover by natural processes is slow and that both abiotic and biotic drivers affect soil structure. Turnover under dry climatic condition was significantly slower due to lower biological activity. When soil is mixed by fauna > 30 µm activity, the distribution of garnet particles originally located at the surfaces of macro-aggregates became increasingly randomised, indicating rearrangement of soil structure and establishment of new pore−soil matrix interfaces.
Soil methane (CH4) fluxes in cropland with permanent pasture and riparian buffer strips with different vegetation
Authors: Dlamini Jerry , Cardenas Laura , Tesfamariam Eyob , Dunn Robert , Hawkins Jane , Blackwell Martin , Evans Jess , Collins Adrian
Published: March 2022

Methane (CH4) has a global warming potential (GWP) 28-times that of carbon dioxide (CO2) over a 100-year horizon. Riparian buffers strips are widely implemented for their water quality protection functions along agricultural land, but conditions prevailing within them may increase the emissions of greenhouse gases (GHGs), including CH4. However,  only small amount of information is available regarding the dynamics of unintended emissions of soil CH4 in these commonplace features of agroecosystems and how the dynamics compare to those for agricultural land not containing buffer strips. To understand the dynamics of soil CH4 fluxes from a permanent upslope pasture and contiguous riparian buffer strips with different (grass, willow, and woodland) vegetation as well as controls with no buffer vegetation, field measurements were carried out using the static chamber technique on a replicated plot-scale facility. Gas fluxes were measured periodically with soil and environmental variables between June 2018 and February 2019 at Rothamsted Research, North Wyke, United Kingdom. Soils under all treatments were sinks of soil CH4 with the willow riparian buffer (-2555 ± 318.7 g CH4 ha-1) having the lowest soil CH4 flux followed by the grass riparian buffer (-2532 ± 318.7 g CH4 ha-1), woodland riparian buffer (-2318.0 ± 246.4 g CH4 ha-1), no-buffer control (-1938.0 ± 374.4 g CH4 ha-1), and lastly, the upslope pasture (-1328.0 ± 89.0 g CH4 ha-1) which had a higher flux. The three vegetated riparian buffers were more substantial soil CH4 sinks, suggesting that they may help reduce soil CH4 fluxes into the atmosphere in similar agroecosystems.
Skilful US Soy-yield forecasts at pre-sowing lead-times
Authors: Vijverberg Sem , Coumou Dim , Hamed Raed
Published: March 2022

Soy harvest failure events can severely impact farmers, insurance companies and raise global prices. Reliable seasonal forecasts of mis-harvests would allow stakeholders to prepare and take appropriate early action. However, especially for farmers, the reliability and lead-time of current prediction systems provide insufficient information to justify for within-season adaptation measures. Recent innovations increased our ability to generate reliable statistical seasonal forecasts. Here, we combine these innovations to predict the 1-3 poor soy harvest years in eastern US. We first use a clustering algorithm to spatially aggregate crop producing regions within the eastern US that are particularly sensitive to hot-dry weather conditions. Next, we use observational climate variables (sea surface temperature (SST) and soil moisture) to extract precursor timeseries at multiple lags. This allows the machine learning model to learn the low-frequency evolution, which carries important information for predictability. A selection based on causal inference allows for physically interpretable precursors. We show that the robust selected predictors are associated with the evolution of the horseshoe Pacific SST pattern, in line with previous research. We use the state of the horseshoe Pacific to identify years with enhanced predictability. We achieve very high forecast skill of poor harvests events, even 3 months prior to sowing, using a strict one-step-ahead train-test splitting. Over the last 25 years, 90% of the predicted events in February were correct. When operational, this forecast would enable farmers (and insurance/trading companies) to make informed decisions on adaption measures, e.g., selecting more drought-resistant cultivars, invest in insurance, change planting management.
GDNDC (v2.0): Modelling long-term soil acidification of cropland under different fertilization scenarios
Authors: Huang Xiao , Yu Chaoqing
Published: March 2022

Soil pH is one of the most important properties for soil health, affecting the microbial activities, aggregate structure, nutrient availability and soil toxicity. For croplands in China, intensive application of ammonium-based fertilizer, as well as increased rate of nitrogen deposition, are inducing significant soil acidification in the long term and therefore threating agricultural sustainability. However, in almost all process-based biogeochemical models, soil pH is used as model input (constant) but its dynamic (especially at decadal scale) has not been simulated properly. In this study, we developed the new soil pH module in GDNDC (Gridded version of DeNitrification and DeComposition model) model to simulate the evolution of soil acidification processes within 0-40cm depth and its effect on crop growth. Using charge balance as the principle, different equations based on the chemical equilibrium between H+, NH4+, NO3-, Al3+, base cations (e.g. Mg2+, Ca2+ and K+), organic anion (Org-) and CO2 were integrated into the new model and then numerically solved at daily step. Over 20-year field observations (e.g. soil nitrogen content, soil pH, crop yield, etc) under different fertilization scenarios (including non-fertilizer, inorganic NPK only, organic manure only, and inorganic NPK + organic manure) from both Qiyang and Jinxian sites in China were used to validate the accuracy of model’s prediction. By comparing the model outputs with field measurements, we found the GDNDC (v2.0) could effectively capture the unique trend of soil pH evolution under different fertilization scenarios at decadal scale, for example, the accelerated soil acidification under NPK and the buffering effect of organic manure. The difference of crops yield under different fertilization scenarios was also predicted precisely. As a result, our model has the capacity to simulate the dynamic of soil pH under various fertilization schemes and it can make a great contribution to long-term policy making on improved fertilization for agricultural sustainability.
Injection-induced sequences give us insights about what is happening at depth during natural earthquake swarms
Authors: Danre Philippe , De Barros Louis , Cappa Frédéric
Published: March 2022

Natural earthquake swarms occur in various geological contexts, and are usually interpreted as driven by fluid pressure diffusion. However, little is known about their fluid-driving processes, as no direct observations of either fluid and deformation are possible at such depths. To improve our understanding of the processes involved in swarms, we develop a quantitative comparison between natural and injection-induced swarms. Fluid injections in the crust, for instance geothermal reservoir development or wastewater storage, are accompanied by a prolific seismicity, that can be related to the fluid-pressure perturbation and potentially in association with aseismic slip at depth. It is well-accepted that the released seismic moment scales with injected fluid volume, but proposed relations usually not consider the contribution of aseismic deformation. Constraining such a relation might provide information on what happens at depth during natural earthquake swarms. Indeed, based on the numerous similarities observed between natural and injection-induced swarms, we confirm that both types of sequences seem to obey the same physics. In our work, we establish a framework to relate seismic observables to the fluid volume circulating at depth. This allows us to quantify aseismic slip for all types of swarms, but also to estimate the volume of fluids circulating at depth during natural earthquake swarms. By focusing on several natural swarms, this sheds a new light on the processes driving swarms of seismicity.
Optimizing the operating rule of a controversial interbasin water transfer: the Tagus-Segura aqueduct (Spain)
Authors: Valerio Carlotta , Giuliani Matteo , Castelletti Andrea , Garrido Alberto , De Stefano Lucia
Published: March 2022

Interbasin water transfers (IBWT) are often conceived as solutions to balance freshwater's uneven spatial and temporal distribution. Climate change, increasing water demand and water quality deterioration are expected to further increase the importance of water transfer schemes in future. At the same time, IBWT are often controversial and raise concerns about their social, environmental and economic impacts.

The Tagus-Segura aqueduct (TSA) in Spain is among the major IBWT projects existing in the world. It is designed to transfer a maximum of 650 hm3/year from the Entrepeñas and Buendía dams in the Tagus headwaters river basin to the Segura river basin for irrigation and urban water supply purposes. The reduction of the natural runoff registered since the 80ies, the implementation of a non-optimal operating rule and, finally, the degradation of the Tagus river ecosystems have generated strong, still unsolved tensions between donor and receiving regions.

In this study, we employ the Evolutionary Multiobjective Direct Policy Search (EMODPS) to optimize the operation of the TSA with respect to four potentially conflicting objectives: the Tagus (i) and the Segura water demands (ii); hydropower production downstream of the Entrepeñas and Buendía dams (iii) and the social-economic benefit of the population living on the shores of the reservoirs (iv). The release decision parameters and the operating rule parameters are jointly optimized, thus allowing the exploration of trade-offs between objectives and the definition of an operating rule that could benefit all the stakeholders involved. We tested the optimization under several scenarios, with the aim to assess the effect of the implementation of different environmental flows in the Tagus river on the TSA operations.

By applying a state-of-art method such as the EMODPS to the TSA case, this work contributes to the intense ongoing debate on the present and future of this controversial water transfer in Spain. We also explore the potential of the EMODPS approach to guide the design of efficient and sustainable operating rules of water transfers, with the ultimate goal of mitigating tensions between recipient and donor regions and seeking to fulfil the environmental needs in the donor basin.
Scenarios of social-environmental extremes 
Authors: Messori Gabriele , Rusca Maria , Di Baldassarre Giuliano
Published: March 2022

In a rapidly changing world, what is today an unprecedented environmental extreme event may soon become the norm. Such unprecedented events, and the related disasters, will likely have highly unequal socio-economic impacts. We investigate the relation between genesis of unprecedented events, accumulation and distribution of risk, and recovery trajectories across different societal groups, thus conceptualising the events as social-environmental extremes. We specifically propose an analytical approach to unravel the complexity of future extremes and multiscalar societal responses-from households to national governments and from immediate impacts to longer term recovery. This combines the physical characteristics of the extremes with examinations of how culture, politics, power and policy visions shape societal responses to unprecedented events. As end result, we build scenarios of how different societal groups may be affected by, and recover from, plausible future unprecedented extreme events. This new approach, at the nexus between social and natural sciences, has the concrete advantage of providing an impact-focused vision of future social-environmental risks, beyond what is achievable within conventional disciplinary boundaries. In this presentation I will illustrate an application to a future extreme flooding event in Houston. However, the approach is flexible and applicable to a wide range of extreme events.

 
Multi-Criteria Decision Making for Site Suitability of a Solar Farms 
Authors: Mudholkar Lalit , Haridas Aithal Bharath
Published: March 2022

 The global electricity consumption is increasing at a faster rate than total global power production. Non-renewable sources contributed more than 63.3% of global electricity production in 2020, and such a high reliance on non-renewable sources could lead to electricity shortages and environmental issues. This alarming situation is on the doorstep as various countries in the world are facing electricity crises. Solar energy can be an alternative to tackle this problem and to achieve the Sustainable Development Goal (SDG) of affordable and clean energy. There are several environmental factors that affect the efficiency of solar panel. Thus, based on the nature and working principle of photovoltaic cell, there is a need to prioritise these factors to locate suitable locations to increase the efficiency of both transmission and generation. Solar panel being expensive capital component, meticulous planning of such projects is necessary as it has long payback period, substantial investment, and relatively lower returns on investment. This study emphasises on two components, first the method of finding a suitable location with several required parameters through geospatial data analysis and the second being financial feasibility by identifying suitable locations of execution and maintenance costs that will be as minimal as possible without compromising the efficient solar locations. Higher efficiency and lower cost locations will together increase sustainability and affordability that contribute to achieving the SDG of affordable and clean energy. 
Origin, accumulation and fate of dissolved organic matter in an extreme hypersaline shallow lake.
Authors: Butturini Andrea , Herzsprung Peter , Lechtenfeld Oliver , Alcorno Paloma , Benaiges-Fernandez Robert , Berlanga Merce , Boadella Judit , Freixinos Campillo Zeus , Gomez Rosa , Sanchez-Montoya Maria del Mar , Urmeneta Jordi , Romaní Anna
Published: March 2022

Hyper-Saline Endorheic Aquatic Systems (H-SEAS) are shallow lakes in arid and semiarid climatic zones that undergo to extreme oscillation in salinities and large drought episodes. Although their geochemical uniqueness and microbiome are deeply studied, very little is known about availability, transformation and fate of dissolved organic matter (DOM) in water column, interstitial waters and in salts that precipitate under driest conditions. To advance in this direction, a small hypersaline shallow lake from Monegros desert (Zaragoza, NE, Spain) has been studied during a complete hydrological wet-drough-rewetting transition. DOM analysis includes: i) a dissolved organic carbon (DOC) mass balance;  ii) optical spectroscopy (absorbance and fluorescence) characterization and; iii) molecular description by negative electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS).

The studied system stored large amount of DOC and the mass balance revealed that under highest salinity conditions, salt-saturated waters (i.e. brines, salinity >30%) accumulated a disproportionate quantity of DOC indicating a significant net in-situ DOM production. Simultaneously, during the hydrological transition from wet to drought, the DOM pool changed drastically its qualitative properties: thus, aromatic and humified moieties were rapidly replaced by fresher, relatively small size and microbial derived moieties with large C/N ratio. Further FT-ICR-MS highlight the accumulation of small-size, saturated and, highly oxidized molecules (O/C molar ratio >0.5) with a remarkable increase of relative contribution of sugar-like molecules and decrease of aliphatic and carboxyl-rich alicyclic like molecules. Overall, there results highlight that H-SEAS are extremely active in accumulating and processing DOM and, the observed patterns pointed to a notable release of organic solutes from decaying microplankton probably triggered by the osmotic stress under extremely high salinities.

 
Coupling crustal-scale rift architecture with passive margin salt tectonics: a geodynamic modelling approach
Authors: Pichel Leonardo , Huismans Ritske , Gawthorpe Rob , Faleide Jan Inge , Theunissen Thomas
Published: March 2022

Many rifted passive margins are associated with widespread and thick evaporite (i.e., salt) deposits, and pronounced syn-and post-rift salt tectonics. The majority and largest salt basins known-to-date formed during the latest stages of rifting, immediately prior to continental breakup. We use 2D thermo-mechanically coupled finite-element modelling of lithospheric extension to investigate the interplay between variable styles of rifted margin, syn-rift architecture, and consequences for the distribution of late syn-rift salt, and post-rift salt tectonics. We simulate the formation of salt basins in different types of continental margins: narrow, intermediate, wide, and ultra-wide margins. For each of these, we evaluate: 1) the interplay between rifting, post-rift sediment progradation, base-salt topography and margin scale salt tectonics, 2) the spatial and temporal distribution of salt-related structural domains, and 3) the contrasting styles of salt tectonics for different margin types. We show that narrow and intermediate margins form partially isolated salt basins in their proximal domain with limited translation and significant vertical diapirism. Their distal portions are associated with significant translation, development of updip listric normal faults and rollovers passing downdip to squeezed diapirs. Wide and ultra-wide margins form wide salt basins with a more subtle base-salt topography which result in significant basinward salt expulsion and overburden translation towards their distal domains. These margins are characterized by updip extensional and/or expulsion rollovers and downdip salt inflation, diapirism and shortening in the form of diapir squeezing, buckle-folding and development of allochthonous salt sheets. All margins present a distal salt nappe that varies in width for each margin type and forms as a consequence of syn-rift distal salt stretching and post-rift thrusting. These models are the first to integrate lithospheric extension with long-lived post-rift salt tectonics using a geodynamically self-consistent modelling approach where the geometries of the lithosphere and salt basins are not prescribed, allowing a natural evolution of syn and post-rift deformation. They also incorporate a more realistic style of post-rift progradation using a dynamically evolving profile and present unprecedented detail for salt, syn- and post-rift stratigraphy. The results can be directly compared to examples from various salt-bearing continental margins and provide an improved understanding on the kinematics and relative timing of rift and salt deformation, and on the controls and variability of salt tectonics for different margin types.
A statistical analysis of auroral-enhanced plasma lines observed by EISCAT
Authors: Feng Ting , Zhou Chen
Published: March 2022

Plasma lines (PLs) observed by the European Incoherent Scatter Scientific Association (EISCAT) incoherent scatter radar (ISR) data set from 2011 to 2019 are investigated. To statistically analyze the PLs in this large data set, we develop an algorithm for the automatic extraction of naturally enhanced PLs from the ISR spectra. Two typical types of auroral-enhanced PLs at high latitude, namely, secondary electron and electron beam, are analyzed based on this PL extraction algorithm. Our results show that PL enhancements originating from secondary electrons and electron beams present evident magnetic local time dependence and seasonal variations of these enhancements are also investigated. Moreover, the statistical study indicates that the PL enhancements are correlated with the geomagnetic and solar activities. These results can guide future research for the excitation mechanisms and contribute to the understanding of solar wind-magnetosphere-ionosphere coupling mechanisms.
Differential Learning: A method for polar motion time series prediction
Authors: Kiani Shahvandi Mostafa , Schartner Matthias , Soja Benedikt
Published: March 2022

Nowadays, many applications such as Global Navigation Satellite Systems (GNSS) or spacecraft tracking require a rapid determination, or even predictions, of the Earth Orientation Parameters (EOP). However, due to the measurement techniques utilized to estimate EOP, the latency can be considerably longer than required, which especially hinders real-time applications, resulting in a need for accurate EOP prediction methods.

With the resurgence of machine learning in the last decade, time series prediction is increasingly studied in this context. We propose a learning algorithm for the prediction of polar motion components (xp, yp). The algorithm is based on the concept of Ordinary Differential Equation (ODE) fitting. Within this investigation, a general formula for ODE fitting based on multivariate time series is proposed, with special focus on second order ODEs. The mathematical relations are derived and presented in both linear and non-linear forms, particularly with LSTM and Elman neural networks. In addition, a sensitivity analysis framework is proposed for the linear case, which is used for the determination of the importance of features. 

We compared the prediction performance of our method with those from three different studies. First, the conditions of the first Earth Orientation Prediction Comparison Campaign (EOPPCC) are followed. In this case, the ultra-short term predictions (up to 10 days) can be improved on average by 62.5% and 45.6% for xp and yp, respectively,  compared to the best performing EOPPCC method. Second, the prediction performance in long-term prediction (up to one year) is compared against Multichannel Singular Spectrum Analysis (MSSA). In this case, the prediction performance is improved on average for xp and yp by 40.9% and 66.4%, respectively. Finally, comparisons against Copula-based methods for long-term prediction are conducted (average improvement 32.3% for xp and 57.8% for yp).

The advantages of this method include (1) exploitation of physical information via Effective Angular Momentum (EAM) functions and by using the concept of ODE fitting, which often corresponds to the laws governing physical phenomena; (2) presence of sensitivity analysis frameworks; and (3) high predictive performance.