bluuebunny/crossref_metadata_2025 huggingface dataset:
Arctic rapid sea ice loss events in CMIP6 simulations
Authors: Sticker Annelies , Massonnet François , Fichefet Thierry
Published: February 2023

The summer Arctic sea ice is projected to disappear completely by the middle of the century in response to anthropogenic greenhouse gas emissions, according to simulations conducted with the latest global climate models. The decrease in summer Arctic sea ice extent is marked by periods of rapid ice loss, known as rapid ice loss events (RILEs), which are expected to become more frequent in the coming decades. However, the causes of RILEs are not well understood and it is difficult to predict their occurrence a season to several years ahead. It is essential to improve our understanding of these events and their potential impacts on ecosystems and societies, as the rate of sea ice decline can affect the ability to adapt to rapid change. To gain a better understanding of RILEs, we conducted an analysis using climate simulations from the Coupling Model Intercomparison Project phase 6 (CMIP6). Our results show that the frequency of RILEs increases as the Arctic sea ice extent diminishes, and the probability of observing a RILE is highest during the period from 2025 to 2030. Moreover, the observed September Arctic sea ice extent is critically approaching the value corresponding to the peak of probability of occurrence of RILEs. This suggests that we may be on the verge of a new RILE, following a slowdown since the early 2010s. In the future, we plan to identify the climatic conditions that are favorable for the formation of RILEs, with the goal of predicting the probability of their occurrence in real-time. We also aim to study the impacts of these rapid ice loss events on the wider climate system. 
Relationships of the Diurnal Pulse to Structure and Intensity of Tropical Cyclones
Authors: Zhang Xinyan , Xu Weixin
Published: February 2023

The radially-outward propagating, cloud-top cooling, diurnal pulse (DP) is a prominent feature in tropical cyclones (TCs) that has important implications for changes in TC structure and intensity. By using an objective diurnal-pulse identification algorithm, this study characterizes DPs both globally and regionally over various ocean basins and examines their relationships to TC structure and intensity. Active DPs (ACTDPs) occur on 52% of TC days globally. They are the most frequent over the Northwest Pacific (NWP, 60.4%). The median duration and propagation distance of ACTDPs are 12–15 h and 500–600 km, respectively. Some ACTDPs (20–25%) last longer than 18 h and propagate as far as 700–800 km. Although the mean propagation speed of ACTDPs is 11–13 m s-1, persistent ACTDPs (lasting >15 h) mostly propagate at speeds similar to internal inertial gravity waves (5–10 m s-1). Most ACTDPs initiate in the inner core overnight, in phase with inner-core deep convection. Nearly half of the ACTDPs are coupled with the outward propagation of precipitation within TCs. The TC inner-core deep convection is significantly enhanced on ACTDP days. Specifically, the 20 dBZ echo top in the upshear quadrant of TCs rises the most evidently with the occurrence of the ACTDP, leading to a more symmetric structure of the inner-core convection. The occurrence ACTDPs may promote the rapid intensification (RI) of TCs. The frequency and duration of ACTDPs are strongly correlated with the TC intensification rate. RI TCs have a markedly higher frequency of the very long-duration ACTDPs (≥15h) and longer mean pulse duration than steady-state and gradually intensifying TCs. Overall, the DP is a potentially useful signal for the RI of TCs.
Why are some faults in the Alps active, and others not? Answers from stress-induced anisotropy of nonlinear elasticity
Authors: Aiman Yongki Andita , Delorey Andrew , Lu Yang , Bokelmann Götz
Published: February 2023

Major faults such as the Periadriatic Fault and the Giudicarie Fault have been active in the past, and they have even been central features of the larger-scale deformation in the Alps. It seems that these faults are not active anymore though and we investigate why this is so by inspecting the orientation of the regional stress field which loads the faults mechanically. The orientation of maximum horizontal compressive stress (SHmax) is commonly estimated from in-situ borehole breakouts and earthquake focal mechanisms. Borehole measurements are expensive, and therefore sparse, and earthquake measurements can only be made in regions with many well-characterized earthquakes. Here we derive the stress-field orientation using stress-induced anisotropy in nonlinear elasticity. In this method, we measure the strain derivative of velocity as a function of azimuth. We use a natural pump-probe approach which consists of measuring elastic wave speed using empirical Green’s functions (probe) at different points of the earth tidal strain cycle (pump). The approach is validated using a larger data set in the Northern Alpine Foreland region where the orientation of SHmax is known from borehole breakouts and drilling-induced fractures. The technique resolves NNW-SSW to N-S directed SHmax which is in good agreement with conventional methods and the recent crustal stress model. The technique is then applied to the Southern Alps to understand the contemporary stress pattern associated with the ongoing deformation due to the counterclockwise rotation of the Adriatic plate with respect to the European plate. Our results explain why the two major faults in Northeastern Italy, the Giudicarie Fault and the Periadriatic Line (Pustertal-Gailtal Fault) are currently inactive, while the currently acting stress field allows faults in Slovenia to deform actively. We have demonstrated that the pump-probe method has the potential to fill in the measurement gap left by conventional approaches, both in terms of regional coverage and depth. 
A meteotsunami in the north Indian Ocean triggered by Hunga Tonga volcanic eruption.
Authors: Nambiathody Anup , Vijayakumaran Vijith , Balakrishnan Rohith , Puthiyadath Sreeraj , Rose Linta , Sabu Arjun , Kumar B L Sudeep , Krishnapillai Sukumarapillai Krishnamohan , Anakuzhikkal Sudarsanan Sunil , Poikayil Sukumaran Sunil
Published: February 2023

The Hunga Tonga Volcano in the southwest Pacific islands of Tonga erupted in January 2022. The massive explosion resulted in the generation of Lamb waves that propagated globally with a speed of ~ 300m/s and generated a tsunami that has affected numerous Pacific countries. In this study, we use observations and a numerical model to show the impact of this volcanic eruption on the Indian coastline. The Lamb wave took roughly 10 to 11 hours to reach the Indian coast, as observed in atmospheric pressure at mean sea level. Further, the signatures of high-frequency sea-level perturbations were observed from coastal tide-gauge networks along the Indian coastline. Our analysis shows that sea-level oscillations with considerable amplitude (10-20 cm) were observed along the Indian coastline during this period. The predominant frequency and amplitude, and oscillation were different at different locations. Further, an asymmetry between east and west coast stations was observed in the nature of high-frequency oscillations forced by the Hunga Tonga volcanic eruption. Finally, a numerical model was utilised to demonstrate how topography contributes to the observed sea-level disturbances. The model simulations imply that bathymetry is crucial to the observed sea-level variability. Thus, a 12000 km away event has significantly impacted the sea level along the Indian coastline. This work paves the way for understanding the importance of high-frequency variabilities along the Indian coastline and discusses the necessity to enhance the capability of our early warning systems by incorporating these variabilities.
Strength of the lithosphere derived by geological and geophysics data: the Graham Land (Antarctic Peninsula) case study
Authors: Linsalata Fernando , Spada Giorgio
Published: February 2023

We explore the strength of the lithosphere beneath the Graham Land region (Antarctic Peninsula) using numerical modeling which simulate lithospheric deformation as a function of geological and geophysical parameters. First, we process 21 GNSS time series data spanning 1997–2022 provided by the Nevada Geodetic Laboratory, to produce a robust tectonic velocity solution and calculate a new geodetic strain rate model using an optimal mesh grid definition of 0.5 x 0.5 degrees that best fits our study area. Second, we combine our new geodetic strain rate model with the Moho depth and rheological parameters such as geothermal heat flow (GHF), heat productions and thermal conductivity previously published in the literatures to determine yield strength envelope (YSE) along three profiles (A, B and C respectively) beneath Graham Land. The lithospheric strength values are in a range from 0 to 500 MPa and depend more on strain-rates at the surface and thermal regime (GHF) than on crustal thickness. The highest values for the crust (500 MPa) are mostly concentrated in the profile A, near Cape Alexander, where the second invariant of the strain rate present the smaller value (5-15 μstrain/yr) and the principal strain rates are compressive approximately in the N-S directions. In contrast, the highest values for the mantle mainly depend on the thermal structure of the lithosphere and Moho depth and the highest values are concentrated in the profiles B (297 MPa) and C (279 MPa), in the Trinity Peninsula. Here, the second invariant of the strain rates, present the larger value (50-80 μstrain/yr) and the principal strain rates are extensive in the W-E directions, with a maximum value of 30 μstrain/yr. The results of our study demonstrate that both “jelly sandwich” and “crème brûlée” models are valid for the Graham Land lithosphere, depending on specific thermal and rheological conditions considered.
Climate and mineral controls on global soil radiocarbon profiles
Authors: von Fromm Sophie F. , Hoyt Alison M. , Doetterl Sebastian , Trumbore Susan E.
Published: February 2023

Radiocarbon measurements provide a powerful tool to assess the persistence of soil organic carbon (SOC). While soil depth is generally one of the most important predictors of soil radiocarbon age, it remains unclear whether this relationship is due to an overall decrease in C input with depth or to changing importance of climatic or mineralogical constraints on SOC decomposition. Due to this lack of mechanistic understanding, we argue that the relationship between soil radiocarbon age and SOC abundance may be a better proxy than depth to investigate SOC persistence. To test this hypothesis, we use globally collected soil radiocarbon data from the International Soil Radiocarbon Database (ISRaD) to examine the influence of climate and soil mineralogy on the relationship between SOC concentration and radiocarbon age at the profile level. Our analysis includes about 600 soil profiles covering all major climatic zones and soil types (except aridisols). We show that extreme climatic and mineralogical constraints can lead to a similar accumulation of old SOC throughout the soil profile but for very different reasons. Climatic extremes include soils from tundra/polar regions where C input and decomposition are constrained by low temperatures and water availability. Mineralogical extremes include volcanic soils (andisols) that are dominated by highly reactive amorphous minerals that limit SOC accessibility. Across all climate zones and for a given SOC concentration, arid soils tend to have younger radiocarbon ages compared to temperate soils. Tropical soils have the youngest SOC at the surface due to high C input and show a relatively uniform distribution of SOC and radiocarbon ages globally. In terms of mineralogy, soils dominated by low-activity clays (oxisols and ultisols) show younger radiocarbon ages than soils dominated by high-activity clays (all other soil types except andisols) for a given SOC concentration. These first results have far-reaching implications for better understanding SOC vulnerability and benchmarking soil carbon models for representing SOC turnover and persistence across climate zones and soil types.
How to mitigate global change impacts on soil health?
Authors: Rumpel Cornelia
Published: February 2023

There is little doubt that anthropogenic activities have led to profound changes in environmental conditions, which impact biogeochemical cycling and soil functioning. Increasing atmospheric carbon dioxide (CO2) concentrations, global temperature increases, changes in precipitation regimes and more frequent occurrence of extreme events in addition to intensive agricultural practices have adverse effects on soil physical and (micro-)biological properties determining their biogeochemical functioning. In this presentation, I will present the global impacts a and their influence on soil functioning, biogeochemical cycling and ecosystem services in different environments. Feedbacks between the effects of climate change and soil will be presented and soil-based strategies for their mitigation and  adaptation to their consequences will be discussed.
Multi-decadal trends in Antarctic deep convection from satellite-derived steric height
Authors: Cocks Jennifer , Silvano Alessandro , Marzocchi Alice , Naveira-Garabato Alberto , Hogg Anna
Published: February 2023

Deep convection from dense water formation in the Southern Ocean drives the lower limb of the global overturning circulation, sequesters anthropogenic heat and carbon from the atmosphere and ventilates the abyssal ocean. The rate and location of dense water formation and its trajectory to the deep ocean is determined by changes in ocean density and stratification and influenced by ocean-ice-atmosphere interactions such as polynya openings (both open-ocean and coastal), sea ice formation and ice shelf collapse.Signatures of deep convection are logistically difficult to measure. The highest-quality observations of water column density are currently provided by in-situ moorings and profiles from Argo floats or CTDs mounted on elephant seals (MEOP data[1]), but these data are spatially and temporally sparse. Satellite products providing complete coverage of high latitudes at regular repeat periods are becoming more readily available and offer an alternative method for capturing changes the extent and variability of deep-water formation in polar regions. We compute steric height anomalies in the Southern Ocean from 2002-2018 using a novel method combining satellite altimetry and gravimetry data. We use these to explore density changes, focussing on deep water formation regions including the Weddell and Ross seas, the Adelie coastline and Amery shelf region, and infer multi-decadal changes in deep convective processes. Long term changes in the steric height anomalies can be linked to recorded ocean-ice events, such as the 2010 collapse of the Mertz glacier, the 2017 Maud Rise polynya and recent recovery of Ross Sea Bottom Water. The satellite-derived steric height anomalies have been validated against in-situ Argo and MEOP profiles and show good agreement in regions with a high data density.
[1]https://meop.net/meop-portal/
Sedimentation rates across Baffin Bay since the last glacial period (based on radiocarbon age control)
Authors: Okuma Emmanuel , Titschack Jürgen , Kienast Markus , Hebbeln Dierk
Published: February 2023

Around Baffin Bay, the large continental Laurentide, Innuitian, and Greenland ice sheets retreated from their maximum extent reaching the shelf break during the Last Glacial Maximum (LGM) to their present-day close-to-minimum extent being largely confined to onshore settings. The associated changes in ice extent, erosion patterns, and material transport modes probably greatly affected spatial and temporal patterns of sediment deposition in Baffin Bay. While for many sites in Baffin Bay, local information about temporal changes in sedimentation rates exist, a spatial analysis allowing to compare sedimentation patterns is still lacking. To fill this gap, radiocarbon ages from over 50 sediment cores (with two or more dates) across Baffin Bay were compiled to assess the spatiotemporal variability in sediment input to Baffin Bay since the LGM. Preliminary results evaluating sedimentation rates (calculated from un-calibrated 14C ages) binned to 1 ka time slices reveal that during the LGM and the early deglacial, the slope beyond the shelf break and the deep basin were the only active depocenters, however, marked by very low sedimentation rates (mainly <20 cm ka-1), suggesting a largely ice-covered bay. At ~15 ka, sediment supply to these settings increased, likely reflecting the onset of ice retreat during the deglaciation. With the beginning of deposition on the mid and outer shelves after ~10 ka, deposition on the slopes and in the basin ceased almost completely. Ongoing ice retreat progressively uncovered new depocenters in the over-deepened shelf troughs off Baffin Island and Greenland, where from ~9 ka onwards, especially the inner shelf off Greenland, experienced elevated sedimentation rates (~100-500 cm ka-1), while Baffin Island fjords received less material (mainly <100 cm ka-1). Most shelf records show a continuous decrease in sedimentation rates since the early Holocene but a few records from the Greenland shelf point to rates picking up over the last two millennia, probably reflecting the Neoglaciation. Sedimentation rates peak after ~6 ka in the wider northern Baffin Bay. These data generally reflect the transition from low glacial to enhanced deglacial sedimentation beyond the shelves, followed by a progressive landward displacement of the main depocenters towards the over-deepened inner shelf troughs. There, sediment input decreased when the ice sheets attained their minimum extent in the mid-Holocene. Only in northernmost Baffin Bay is this trend turned around, with the highest sediment input in the Late Holocene.
State-of-the-art modeling the interaction between microplastic and the low-trophic level marine biota
Authors: Biancardi Anastasia Angela , Zambianchi Enrico , Coppini Giovanni , Liubartseva Svitlana
Published: February 2023

Starting our work on model-based coupling microplastic (MP) and the low-trophic level marine biota, we present a contemporary overview of existing models, both the Lagrangian and Eulerian ones.MP biofouling has been modeled by Kooi et al. (2017), who develop a 1D Lagrangian model to describe size- and density specific vertical motion of MP. They have found thatDenser particles settle sooner than the less dense particles when they have the same size.
The settling velocity decreases with decreasing particle size.
MP particle can oscillate due its buoyancy controlled by biofouling. MP density is balanced by the source-and-sink terms in a biofouling equation for algae attached to the MP surface.
Oscillation periods increase with decreasing particle size.
 Lobelle et al. (2021) improve the Kooi et al. (2017) model developing a 3D Lagrangian model with horizontal and vertical advection. They consider a global distribution of MP of different size and density and note that the timescale is largely size-dependent as opposed to density dependent.Finally, Fischer et al. (2022) modify the physics part of the model by Lobelle et al. (2021), focusing on the vertical movement, both vertical advection and vertical turbulence diffusion. Additionally, they add two loss terms in the biofouling equation. They conclude that the vertical movement of particles is mainly affected by wind induced mixing within the upper mixed layer and by biofilm dynamics in the deep ocean.Biofouling as a possible mechanism of the MP removal from the surface has been incorporated into a 3D Lagrangian model for 6 size classes of MP (Tsiaras et al., 2021). In the water column, a sub-surface maximum in MP abundance is obtained, with increasing contribution of smaller particles in deep layers.MP has been embedded in a biogeochemical 3D Euler model by Kvale et al. (2020), who consider the processes of MP aggregation in sinking marine snow and faecal pellets in the global ocean. In the subsequent work (Kvale, 2022), a two-way coupling developed in the model allows finding a way of the MP influence on global marine carbon cycling and climate.Biofouling, the MP transport by marine snow and fecal pellets have been simulated by Berezina et al. (2021), who incorporate MP into a biogeochemical 2D Euler model with translational symmetry. They reveal that the so-called “biological pump” (or vertical transport of MP by marine snow and fecal pellets) can be one of the important drivers controlling the distribution of MP in the water column and bottom sediments in the Oslo Fjord.A new Lagrangian model that we plan to implement in the future will help to advance our understanding of biota-mediated processes in MP transport and fate in the Mediterranean Sea.
Observational Evidence Reveals Growing Spatial Scales of Compound Occurrence of Humid Heat Stress-Extreme Rainfall in India
Authors: Ganguli Poulomi
Published: February 2023

Extreme heat under the warming environment has direct societal implications for developing and highly urbanized populations. Previous studies have shown that extreme wet-bulb temperature, a multivariate measure of temperature-humidity, has led to anomalously high convective inhibition and increased precipitation intensity over the tropics. However, little is known about the linkage of humid heat stress characteristics, such as duration and peak heat stress, versus the sub-daily precipitation extremes over urban and periurban locations in the tropics. Leveraging ground-based meteorological records of around five decades from the 27 hydrometric observatories of the India Meteorological Department, I investigate the compound occurrence of humid heat stress versus sub-daily precipitation extremes across the Indian subcontinent (4 - 40° latitude and 65 - 100° longitude). Here heatwaves are identified when three or more consecutive days of extreme wet-bulb temperature, Tw, is above the 90th percentile daily variable threshold for each day of the year.  I show the impact of heat stress and its duration on sub-daily precipitation extremes using a novel conditional probabilistic approach. The risk of sub-daily precipitation extremes at each urbanized location is modelled considering the nonstationarity of underlying drivers. The relative timings between each driver and duration overlap between heatwaves and above-average precipitation extremes (wet spells) are also shown. The results show that the extremal upper dependence between peak Tw and sub-daily precipitation extremes are significantly positive and lies in the range of 0.12 to ≥0.20 across the central northeast region that housed part of the Indo-Gangetic Plains. More than 40% of sites report the most coinciding occurrence of humid-heat stress versus sub-daily precipitation extreme, where each of these drivers readily overlapped each other with a lag time of fewer than two days. Further, I show that considering the magnitude of heat stress as a 10-year return period, even a moderate increase in duration will increase the probability of sub-daily precipitation extremes by a range of 1.7 to 20%, with a notable increase across coastal cities. These results are supported by the physically consistent theory suggesting an increase in sub-daily rainfall extremes in response to climate warming over lands of the tropics because of the combination of “positive thermodynamic” and “dynamic contributions.” The observational evidence of increased sub-daily precipitation extremes in response to humid heat stress would help stakeholders and international organizations build resilient strategies to mitigate the impacts of such consecutive hazards.
Metal mineral classification under microscope images using deep learning
Authors: Cai Yiwei , Qiu Kunfeng , Hou Zhaoliang
Published: February 2023

Analysis of optical microscopic image data is crucial for identifications of mineral phases, and thus directly relevant to the subsequent methodology selections of the further detailed petrological exploration. So far, large-dimensional image analyses are dominantly based on digital image datasets, and the automatic identification of the optical microscopic data is still poorly examined. Here, by testing the Swin Transformer, a deep learning algorithm on different metal mineral phases, we proposed a well-behaved mineral recognizer with high accuracy of 92.8% and strong global ability. In addition, we apply Class Activation Mapping (CAM) is introduced for the first time in mineral identification tasks and reveals the interpretability of the models, allowing us to more intuitively observe that mineral edges are the most effective model identification features. The results demonstrated that optical microscope data can not only rely on pixel information, and machine learning can accurately extract all available attributes, which reveals the potential to assist in data exploration and provides an opportunity to carry out spatial quantization at a large scale (cm-mm).Keywords: Metal mineral; Microscope images; Deep learning; Swin Transformer; Class Activation Mapping
Characterising errors using satellite metadata for eco-hydrological modelling
Authors: Zou Hui , Marshall Lucy , Sharma Ashish
Published: February 2023

Understanding the origin of errors in model predictions is a critical element in hydrologic model calibration and uncertainty estimation. While there exist a variety of plausible error sources, only one measure of the total residual error can be ascertained when the observed response is known. Here we show that collecting extra information a priori to characterise the data error before calibration can assist in improved model calibration and uncertainty estimation. A new model calibration strategy using the satellite metadata information is proposed as a means to inform the model prior, and subsequently to decompose data error from total residual error. This approach, referred to as Bayesian ecohydrological error model (BEEM), is first examined in a synthetic setting to establish its validity, and then applied to three real catchments across Australia. Results show that 1) BEEM is valid in a synthetic setting, as it can perfectly ascertain the true underlying error; 2) in real catchments the model error is reduced when utilizing the observation error variance as added error contributing to total error variance, while the magnitude of total residual error is more robust when utilizing metadata about the data quality proportionality as the basis for assigning total error variance ; 3) BEEM improves model calibration by estimating the model error appropriately and estimating the uncertainty interval more precisely. Overall, our work demonstrates a new approach to collect prior error information in satellite metadata and reveals the potential for fully utilizing metadata about error sources in uncertainty estimation.
Characteristics of microplastics in different media in Jiaozhou Bay, China
Authors: Zheng Shan , Sun Xiaoxia , Zhang Kangning
Published: February 2023

In the current global environmental problems, marine plastic pollution, ozone depletion and ocean acidification are included. With the development of research on microplastics, we have obtained important understandings on the temporal variation of the spatial distribution characteristics and the spatial variation of the temporal distribution characteristics of microplastics in China’s coastal waters. However, due to the complexity of microplastics features, the study of microplastic sources is in a relatively preliminary stage. Based on topographic features and chemical composition, an integrated index for microplastics complexity (MCI) was developed, and was applied in reflecting microplastics complexity in different media in Jiaozhou Bay. We compared the differences in microplastic complexity in wastewater treatment plants (WWTPs) and seawater, sediments and biota by in Jiaozhou Bay. MCI range from 0.35 to 57, with the average of 0.49 in wastewater in WWTPs. The MCI in zooplankton, which was 0.3 in average. The MCI in zooplankton is rather lower than that in the seawater, as zooplankton are so small as not to ingest large size particles of microplastics. The MCI of benthic shellfish was 0.46, which was higher than that in zooplankton, indicating that the complexity of microplastics in benthic shellfish were higher. The results of the study suggest that the value of MCI can be used for quantitative analysis of microplastic source apportionment. The MCI in wastewater in WWTPs, seawater, sediments, shellfish, and zooplankton showed the complexity of microplastic contamination in each phase and the connection between different media. Quantitative source apportionment is continuing to further promote the accomplishment of goal 14.1 in SDGs and decision support.
Active tectonics and Fault behavior analysis based on deformation of mud layer on Wuhe Tableland, Eastern Taiwan
Authors: Panday Suman , Dong Jia-Jyun , Yen Jiun-Yee , Lu Chih-Heng , Yang Che-Ming
Published: February 2023

The fragile geology, tectonically and active seismic mountain belt like Taiwan are exposed to numerous geological controls on development of landforms. Especially North-South elongated suture zone between Eurasian and Philippine sea plate formed a Longitudinal valley remarks very active seismic behaviors and bounded by west dipping Central Range Fault (CRF) and east dipping Longitudinal Valley Fault (LVF). Wuhe table land lies on the western side of central part of valley and approximately 200 meters elevated from Xiuguluan River bed. The unconsolidated Mud layers (>50 ka) with few carbonaceous materials of about ten meters’ thicknesses lies in thick conglomerates of tableland could be the lacustrine deposits based on sedimentary environment, which suggest that there was a short-term damming event which is inclined approximate 30 degrees towards northwest. Deformation of mud layer is further studied to analysis the active tectonics and structural controls on tableland. Numerous boreholes, geophysical prospecting, InSAR data, GPS data and past earthquake information are processed on this study as preparation of 3- dimensional geological model and deformation characteristics. Past earthquake behavior shows that CRF acts as blind strike slip movement and very less surface deformation or ruptures but small-scale fissuring on south along Yuli ruptures (Yuli fault trace from 1951 earthquake) from the tableland and the upliftment rate of tableland is slow approximately about   >1mm/year.  While there are debatable issues regarding to CRF mechanism but this research tries to correlate the active deformation behavior and preservation of Wuhe Tableland on the basis of fault characteristics in this region.
Warming rates in a large subtropical shallow Brazilian lagoon
Authors: Tavares Matheus Henrique , Cardoso Maria Angélica , Motta-Marques David , Fragoso Jr Carlos Ruberto
Published: February 2023

Climate change impacts on lake surface water temperature (LSWT) have been mostly investigated in deep northern lakes, and are less understood in southern hemisphere shallow lakes. We evaluated the seasonal warming rates of a large (surface area c.a. 10000 km²) shallow choked lagoon in southern Brazil, with a 22 yr time series of MODIS-derived LSWT, and meteorological data. We found high LSWT warming, with a rate of 0.6°C dec-1 in spring and of 0.3°C dec-1 in summer. We also found a high correlation between water and mean air temperature trends, as well as a substantial shortening of the cold season. Spatially, there was some homogeneity in the warming rates but prominent point spatial differences, which may result from the variability of the tributaries’ temperature or discharge or decreased water transparency. The high warming rates found here are comparable to those found in deep northern lakes although the changes and processes of heating differ. The stronger warming in early spring can result in accelerated process rates and an earlier start of the phytoplankton growing season.
Analysis of water purity and its influence on ecosystems
Authors: Ramona Maghiar
Published: February 2023

The interdisciplinary water study was carried out in Oradea, the analysis focused on water purity and the influence of water quality on the ecosystem.In education programs water is studied by the disciplines of Chemistry, Physics, Biology, Geography and Environmental Sciences.Students from the "Mihai Eminescu" National College in Oradea, guided by their teachers they made some interesting studies about water with an emphasis on the analysis of the Pețea geothermal stream, with endangered endemic species.Water related studies were carried out during the lessons from education programs but also in non-formal education activities. The water analysis was performed with HPLC from the University of Oradea. Students did research about water in specialized institutes, but also in the middle of nature. They studied living plants, insects and animals in wet areas. At the end of the studies carried out with the waters of the area (the Crișul Repede river and the Pețea stream) the students organized workshops and seminars to disseminate their work.
Experimental investigation of the relationship between root:shoot ratio and soil-plant hydraulics.
Authors: Cecere Andrea , Javaux Mathieu
Published: February 2023

In a context of global change, it is crucial to understand the factors and processes by which plants respond to drought and by which crops may limit the development of their aboveground biomass.Experimental studies have showed that soil water status, soil structure and soil texture impact carbon allocation within plant and in particular the root:shoot ratio. We used a conceptual soil-plant hydraulic model to analyze the results of a meta-analysis gathering literature data of root:shoot ratio measured in controlled conditions. For each paper, information on soil water status, soil and plant traits and abiotic factors were collected. Soil hydraulic conductivity was estimated based on pedotransfer functions, when unavailable.The results feature that the root:shoot ratio is an adaptation strategy that depends on the soil conductance in order to balance the water availability with the transpiration demand. The partitioning response varies between plant types. This study gives an explanation to current observations and shows the necessity to collect accurate soil measurements and information for further experiments.  
Realistic uncertainties for Surface Wave dispersion curves and their influences on 1D S-wave profiles
Authors: Piana Agostinetti Nicola , Bonadio Raffaele
Published: February 2023

Surface wave (SW) dispersion curves are widely used to retrieve 1D S-wave profiles of the Earth at different depth-scale, from local to global models. However, such models are generally constructed with a number of assumptions which could bias the final results. One of the most critical issue is the assumption of a diagonal error covariance matrix as representative of the data uncertainties. Such first-order approximation is obviously wrong for any SW practitioner, given the smoothness of dispersion curves, and could lead to overestimate the information content of the dispersion curves themselves.In this study, we compute realistic errors (i.e. represented by a non-diagonal error covariance matrix) for Surface Wave dispersion curves, computed from earthquakes data. Given the huge amount of data available worldwide, realistic errors can be easily estimated using empirical formulations (i.e. repeated measurements of the same quantity). Such approach leads to the computation of a full-rank empirical covariance matrix which can be used as input in standard Likelihood computation (e.g. to drive a Markov chain Monte Carlo, McMC, sampling of a Posterior Probability Distribution, PPD, in case of a Bayesian workflow).We apply our approach to field measurements recorded along one decade in the British Islands. We first compute the empirical error covariance matrices for 12 two-stations dispersion curves, under different assumptions, and, then, we invert the curves using a standard trans-dimensional McMC algorithm, to find relevant 1D S-wave profiles for each curve. We perform both an inversion considering the full-rank error covariance matrix, and one inversion using a diagonal version of the same matrix. We compare the retrieved profiles with published results. Our main finding is that 1D profiles obtained using a full-rank error covariance matrix are often similar to profiles obtained with a diagonal matrix and published profiles obtained with different approaches. However, relevant differences occur in a number of cases, which leads to potentially question some details in 1D models. Given the extreme easiness of computing the full-rank error covariance matrix, we strongly suggest to include realistic error computation in SW studies.
Effect of Channel Bed Roughness on the Mode of Bedload Transport and Signal Response of Impact Plate with an Accelerometer
Authors: Sahu Bidhan Kumar , Mohapatra Pranab Kumar
Published: February 2023

Studying bedload transport is essential for analysing erosion and deposition processes in the channels and designing hydraulic structures. Impact plate systems are indirect devices deployed to measure bedload consisting of a metal plate. When the bedload sediments strike the plate, they create vibrations which are recorded as signals by an acoustic sensor attached to the plate. The signal acquired is then processed to find the bedload properties. Flow velocity and mode of bedload transport can affect the signal. The effect of velocity on the impact plate signals is well documented in the literature. However, the role of channel bed roughness which hugely influences the mode of transportation of bedload, is yet to be studied in detail. This study investigates the effect of channel roughness on the mode of bedload transport and the signal registered in an impact plate in a laboratory flume. The impact plate is placed at the downstream end such that the top plate of the box is aligned with the bed of the flume. An accelerometer sensor is attached to the underside of the plate to record the vibrations. The bed of the flume 2.5m upstream of the impact plate is composed of a replaceable “rough” section. Four different tests are conducted considering four separate rough sections (smooth, 2mm, 5mm, and 10 mm). The bedload particles are sorted into five classes based on their size, from 2.36mm to 20mm. In each test, the particles from a particular grain size class are manually released 5m upstream of the impact plate. The signal generated from the bedload strike is used to develop a calibration equation relating to bedload size and channel roughness. A digital camera is used to capture the bedload movement over the plate to link the mode of bedload transport with the signal.
Widespread occurrence of high radium concentrations in bottom waters of the Eckernförde and Kiel bays (Western Baltic Sea): Are these related to submarine groundwater discharge?
Authors: Scholten Jan , Schroeder Jan , Hsu Feng-Hsin , Liebetrau Volker
Published: February 2023

The radium isotopes (224Ra, t½ = 3.7 d;223Ra, t½ =11.5 d; 228Ra, (t½ = 5.7 y); 226Ra, t½ =1600 y) are well established tracers for the detection and quantification of submarine groundwater discharge (SGD). In the Eckernförde Bay (Western Baltic Sea) SGD associated with pock marks have been observed at many locations on the seabed (~ 20-25m water depths). In order to investigate the spatial and temporal SGD variability we repeatedly measured between 2016 and 2020 the radium (224Ra, 223Ra, 228Ra, 226Ra) distribution in the water column of the Eckernförde Bay and the adjacent Kiel Bay. In general, the water-column radium profiles are characterized by relatively low radium concentrations in the upper water column (~ <15m water depth, salinity ~ 12-18) and significantly higher ones in deep waters (~ 20-25m water depth; salinity ~ 21-25). High radium occurs also in areas far off the coast where pock marks have previously not been reported. Monthly/bi-monthly measurements at the time-series station Boknis Eck (Eckernförde Bay) revealed that this high radium occurs only between spring and autumn, a period, where bottom waters have low or negligible oxygen content. This observation may indicate that processes other than SGD may contribute to seasonal changes in deep water radium. In the presentation possible other radium sources like e.g., diagenetic radium supply from anoxic sediments, sediment bioturbation and resuspension, advection of deep waters from the North Sea, are discussed in order to understand to what extent the radium distribution in the western Baltic Sea can still be interpreted as a tracer of SGD.
The relation between GPS loss of locks and the Interplanetary Magnetic Field orientation: Swarm observations
Authors: Lovati Giulia , De Michelis Paola , Consolini Giuseppe , Pezzopane Michael , Pignalberi Alessio , Berrilli Francesco
Published: February 2023

Swarm enabled researchers to investigate the disturbing phenomena that have affected spacecraft transiting in the F-region ionosphere over the last ten years, in addition to the mission's primary scientific goals. Indeed, plasma density irregularities in the ionospheric region traversed by Swarm satellites can affect both the phase and amplitude of electromagnetic waves propagating through it. As a result, the accuracy and reliability of the Global Navigation Satellite System's (GNSS) performance may be compromised. In the worst-case scenario, a GNSS signal interruption could occur while a Loss of Lock (LoL) event is taking place. This type of events appears to be important in the space weather framework, as it is favored by increased solar activity and disturbed geomagnetic conditions. The high-latitude ionospheric region is particularly impacted by these GNSS signal interruptions.
Here, we look into how the orientation of the interplanetary magnetic field affects the growth of the plasma irregularities that give rise to GPS LoL events. We use LoL events recorded between July 15, 2014, and December 31, 2021, onboard two of the three Swarm satellites, and examine how the orientations of the interplanetary magnetic fields affect the GPS LoL events distribution in magnetic local time and magnetic latitude, in both hemispheres. The results show that there is a clear dependence on the IMF orientation in the y-z plane. The effect of the IMF x component on the LoL distribution is found to be linked to the IMF y component, mainly due to the IMF spiral structure. The results are discussed considering the ionospheric convection patterns as reconstructed by SuperDARN radar observations. The capacity provided by Swarm to track these events and study their dependence on solar, interplanetary, and geophysical parameters may pave the way for a further development of LoL hazard maps at high-latitudes, and thus significantly contribute to space weather effect mitigation.
Optimal lignin decomposition during litter decay
Authors: Chakrawal Arjun , Lindahl Björn , Manzoni Stefano
Published: February 2023

A better understanding of the litter decay process is critical for improved predictions of terrestrial carbon (C) exchange between above and below-ground C reservoirs. Furthermore, developing well-constrained decomposition models with explicit representation of microorganisms is becoming more crucial for improving our understanding of nutrient recycling between soils and plants, greenhouse gas emissions, and the contribution of litter to soil organic matter formation.Litter is typically characterized by structural and non-structural pools—structural components representing the lignin like compounds and non-structural representing soluble and holocellulose organic compounds. Initial litter chemical composition has a strong control on its decomposition. In fact, empirical studies show that a higher initial lignin content in a litter is associated with slower decomposition of holocellulose and implies an increased cost of oxidative enzyme production to break the lignin cross-linked compounds, thereby decreasing microbial community carbon use efficiency. In mathematical models describing litter dynamics, the decomposition rates of these pools are given by the assumed kinetics, either first-order or Monod type, with time-invariant kinetic parameters. This approach neglects possible temporal changes in microbial traits that reflect how decomposer communities adapt to litter chemical properties.Here, we have taken an optimal control approach that does not fix kinetic parameters, but instead finds the decomposition rate constant of the structural (lignin) pool by maximizing the microbial growth (i.e., maximum fitness as a result of natural selection) while taking into account the effect of litter chemistry on microbial metabolism. In this formulation, we combine the soluble and holocellulose C into a non-structural C pool and assume first-order kinetics of decomposition of both structural and non-structural pools. Our results predict a time-varying decomposition rate constant for the lignin pool. This means that optimally adapted microbes would start decomposing lignin at different times as a function of initial lignin content. Further, we provide a case study testing the performance of our model against observed litter decomposition data from a boreal forest. With this contribution, we aim to highlight the applications of eco-evolutionary approaches as an alternate parametrization scheme for litter decomposition models by utilizing microbial life strategy as the main driving factor.
Tracking water movement through a small agricultural catchment using StorAge Selection functions and hydrologic modeling
Authors: Türk Hatice , Hrachowitz Markus , Schulz Karsten , Stumpp Christine , Stockinger Michael , Strauss Peter , Blöschl Günter
Published: February 2023

 Determining the processes that drive streamflow generation and catchment-scale transport of nutrients and pollutants by water is one of the challenges of modern hydrology. In the last decades, substantial knowledge has been gained from high-frequency and high-resolution measurements of tracers to track water movements within a hydrological system. For example, the stable isotopes of oxygen (d18O) and hydrogen (d2H) have been widely used to disentangle the contributions of different runoff generation mechanisms by modeling water travel and residence times. However, quantifying the effects of catchment internal factors for similar or different transit time distributions, particularly in characteristically complex and heterogeneous catchments, remains a challenge. Here we test different shapes for age selection functions (StorAge Selection) of individual distinct storage components (e.g., the root zone, groundwater) of the agricultural Hydrological Open Air Laboratory (HOAL) catchment in Petzenkirchen, Austria. The HOAL has a variety of runoff generation mechanisms, including overland flow, wetlands, and tile drains, as well as high-resolution tracer and hydrological data that allows for broad storage-discharge relationship testing. The main goal of this study is to estimate the transit time distributions associated with varying fluxes from these components (e.g., overland flow, groundwater recharge) to learn about catchment internal streamflow generation processes. Water flow is modeled with a water age balance model and are replaced by selecting the appropriate transfer functions. Testing different age selection functions for various storage components of the catchment will provide a better understanding of catchment dynamics under different environmental conditions, allowing for better calibration of catchment-scale water and nutrient transport models.  