bluuebunny/crossref_metadata_2025 huggingface dataset:
COST-G: release of GRACE-FO RL02 combination
Authors: Jaeggi Adrian , Meyer Ulrich , Lasser Martin , Flechtner Frank , Dahle Christoph , Boergens Eva , Förste Christoph , Mayer-Gürr Torsten , Kvas Andreas , Behzadpour Saniya , Öhlinger Felix , Lemoine Jean-Michel , Bourgogne Stéphane , Koch Igor , Flury Jakob
Published: February 2023

The Combination Service for Time-Variable Gravity Fields (COST-G) is providing monthly gravity fields of the dedicated gravity missions GRACE and GRACE-FO, which are combined from the individual time-series of the COST-G associated and partner analysis centers (ACs). Recently, the operational GRACE-FO combination has been switched to the new RL06.1 time-series of the GRACE-FO science data system (SDS) ACs, which are based on JPL’s new accelerometer transplant product, and to AIUB-GRACE-FO-RL03, which makes use of empirical noise modelling techniques. Moreover, the COST-G weighting scheme was adapted according to the recommendation developed in the Horizon 2020 project Global Gravity-based Groundwater Product (G3P). The so-far existing COST-G GRACE-FO time-series has been re-combined and is now available as RL02. We analyse the quality improvement of the COST-G GRACE-FO RL02 wrt the RL01.
Automatic Detection of Interplanetary Coronal Mass Ejections in Solar Wind in Situ Data
Authors: Rüdisser Hannah Theresa , Windisch Andreas , Amerstorfer Ute V. , Amerstorfer Tanja , Möstl Christian , Bailey Rachel L. , Reiss Martin A.
Published: February 2023

Interplanetary coronal mass ejections (ICMEs) are one of the main drivers for space weather disturbances. In the past, different approaches have been used to automatically detect events in existing time series resulting from solar wind in situ observations. However, accurate and fast detection still remains a challenge when facing the large amount of data from different instruments. For the automatic detection of ICMEs we recently published a deep learning pipeline which has been trained, validated and tested on Wind, STEREO-A and STEREO-B data. We shortly present results of this work and talk about our current attempt to extend its application to a real time scenario in order to investigate its eligibility for functioning as an early warning system.
Overview of the microlitter pollution in the coastal area of the north-eastern Tyrrhenian Sea (Italy): knowledge, innovative monitoring solutions and future perspectives
Authors: Piazzolla Daniele , Scanu Sergio , Bonamano Simone , Della Ventura Giancarlo , Lucci Federico , Piermattei Viviana , Marcelli Marco
Published: February 2023

Anthropogenic litter (AL) is globally recognized as a major challenge due to its multiple environmental, economic, social, political, and cultural implications. It is composed of various materials the most abundant being the plastic. AL is a threat especially in areas with high population densities; with this respect, coastal areas are considered main hotspots of AL pollution. The most abundant and potentially harmful fraction of AL is the microlitter (items < 5 mm) component.In the last three years, several studies concerning microlitter pollution have been conducted in the coastal area of northern Latium (Northern Tyrrhenian Sea, Italy). These studies have provided important information on the quality and quantity of microlitter in different environmental matrices.Microlitter components were classified according to the different shapes (fragments, films, filaments, and microspheres), sizes, colors, and types by visual sorting, optical and scanning electron (SEM) microscopy, while their typology was mainly addressed via spectroscopic (Raman and FTIR) and XRF (X-ray fluorescence) microanalysis.Overall, microplastics (MPs) were found to be abundant in all analyzed samples. MPs abundances were comparable with data from the literature related to the same environmental matrices in the Mediterranean Sea and elsewhere. Coastal sediments showed the presence of particles produced by transport and industrial activities (aluminium silicate microspheres) which contributed 32% of the total microlitter content. Furthermore, coastal waters showed a higher concentration of microlitter items in the water column compared to surface waters.To better investigate the microlitter distribution and fate in the coastal zone, the use of numerical models capable of simulating marine hydrodynamic conditions and predicting the pathways of AL is of particular importance to properly evaluate the litter items trajectories and the presence of potential contamination hotspots. In this context the reliability of predictive models could be enhanced in the next future thanks to the use of new low cost-effective devices and autonomous survey technologies for the acquisition of real-time data with a greater spatial and temporal coverage. To better understand qualitative and quantitative variations of microlitter in coastal areas as well as their distribution, transport, and fate, environmental factors such as rainfall and flood events, which strongly influence the contributions from the continent to the sea and consequently the pollutants load, must be considered. Repeated long-term investigations and seasonal surveys of microlitter pollution could give important information to confirm the obtained results
Towards machine learning-based streamflow drought forecasts across the Colorado River Basin
Authors: Goodling Phillip , Sando Roy , McShane Ryan , Hamshaw Scott , Watkins David , White Ellie , Simeone Caelan , Hammond John
Published: February 2023

Drought is among the most damaging environmental phenomena, affecting agricultural productivity, wildfire risks,  hydropower production, water quantity and quality, public health, ecosystem integrity, and recreation. Streamflow drought, where the streamflow declines below a threshold defining anomalously low flows, is one measure of hydrologic drought that can be interpreted as an integrative measure of the availability of water for specific uses. Early warning of streamflow drought onset, severity, spatial extent, and duration is needed to support improved water resource management. Streamflow drought forecasting is particularly important in the western United States where a changing climate threatens already-scarce water resources.The U.S. Geological Survey is  applying a variety of machine learning and artificial intelligence modeling methods to predict streamflow drought in a 40-year retrospective analysis at 425 USGS stream gage locations within and surrounding the Colorado River basin. In this presentation, we briefly provide an overview of these approaches, then primarily focus on results from random forest binary classification models for streamflow drought onset and duration. For this study, streamflow drought is defined using seasonally variable streamflow exceedance thresholds developed from the Weibull distribution of observed flows or zero-flow durations from 1981-2020. We trained a large set of random forest models (n =72) , each of which predicts daily streamflow drought onset and duration probabilities at a particular forecast horizon and severity level. The models are trained using past observations of daily streamflow drought and a predictor dataset of daily hydrometeorological variables and static basin characteristics We combine the results of these models to provide holistic forecasts. In addition to streamflow drought prediction performance, we evaluate the opportunities for transitioning this modeling framework to operational forecasting and consider future directions for providing actionable forecasts to regional and national stakeholders.
Eco-geomorphological repercussions of recent climate dynamics on soil quality from Cabo de Gata-Níjar Natural Park (Almería, Spain)
Authors: Espinosa-Muñoz Julia , Sillero-Medina José Antonio , Ruiz-Sinoga José Damián
Published: February 2023

In the Mediterranean area of southern Spain, a well-defined rainfall gradient is identified, ranging from 1.000-1.500 mm annual rainfall in the western sector to less than 150 mm in the extreme east. This fact implies a related impoverishment of ecosystem services, intensified by the impacts of current climate dynamics and leading to a degradation of soil-water-plant relationships and reflected in different indicator properties. In this respect, protected natural environments have a fundamental role to preserve and protect ecosystem services. Thus, the mitigation of the effects of climate change on them is a crucial challenge.  For this reason, this study has focused on the Cabo de Gata-Níjar Natural Park (UNESCO Global Geopark), located at the eastern end of the above-mentioned gradient, with territorial characteristics related to arid and semi-arid climatic conditions where the consequences of the current pluviometric pattern are emphasising the vulnerabilities of these areas. This research aims to (i) analyse the eco-geomorphological dynamics in last decades from a climatic and vegetation cover perspective and (ii) contrast this evolution with the soil quality situation, with emphasis on soil organic properties as determinants of the main degradation processes in the Mediterranean area. Methods used combine the statistical analysis of climatic variables based on data from the SAIH Hidrosur Network (1997-2022) with the use of spatial remote sensing techniques by applying vegetation indices in Sentinel-2 images. In addition, a total of 276 soil samples were collected and analysed to determine their physical, hydrological, and organic properties. On a preliminary way, the results show large differences between different landscape units. On the one hand, areas where abiotic factors control the current eco-geomorphological dynamics and where the aggressiveness of rainfall is causing important degradation processes, a reduction in the organic content of soils and, in general, a dynamic associated with rhexistasy, and on the other hand, areas where biotic factors are improving environmental conservation and the prevalence of biostasy processes.
Modelling seismicity based on fault geometry: maximum magnitudes and magnitude-frequency distributions.
Authors: Roche Vincent , van der Baan Mirko , Walsh John
Published: February 2023

Investigating clusters of events and geophysical screening often provides limited constraints on fault geometries. This imaging issue prevents the integration of realistic fault zone geometry into earthquake studies, which can affect our capacity to evaluate the role of pre-existing faults on seismicity. This study describes a modelling strategy accounting for realistic fault zone geometries. Our approach uses stochastic methods underpinned by quantitative fault zone parameterization, followed by an assessment of seismicity from simulations of rupture dynamics controlled by fault geometry. This method is used to investigate the role of fault maturity on seismicity for two case studies, including seismicity associated with the reactivation of a pre-existing fault network due to hydraulic fracturing in Harrison County, Ohio, from 2013 to 2015, as well as the natural seismicity associated with the Yushu-Ganzi left-lateral strike-slip fault system in central-eastern Tibet. In the Harrison County case, we analyze the effect of vertical variability in fault maturity and show how more mature faults in the deeper crystalline basement generate higher magnitude seismicity than shallow, immature faults in younger sedimentary rocks. In the Yushu-Ganzi case study, we show how lateral variability in structural maturity, arising from long-term fault propagation and strain rates, leads to different seismicity on individual fault segments. Our findings indicate that fault geometry determines seismic patterns, with rupture length controlled by fault zone geometry rather than fault lengths, and favour the adoption of a structural geological perspective for the integration of realistic fault geometry into seismicity prediction strategies.
Pangea is a complete supercontinent: paleomagnetic evidence from North China
Authors: Yi Zhiyu , Liu Yushu , Meert Joseph
Published: February 2023

Alfred Wegener proposed the idea of a supercontinent, which he called Pangea about one century ago. The idea led directly to the hypothesis of continental drift, which eventually evolved into the theory of plate tectonics. Pangea is traditionally represented by ~75% of continental crust in which the East Asian blocks (EABs) are typically omitted. Climate models developed using an outboard position of the East Asian blocks led to the hypothesis of a mega-monsoon.Aiming to refine the paleogeography of Pangea, this study reports a new late Triassic paleopole for North China based on dykes and sills sampled from two localities that were ~500 km apart. Laser-ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) U-Pb dating on zircons selected from the sills yields a mean age of 224.4 ± 1.4 Ma. The characteristic remanent magnetizations isolated from the two localities are consistent and pass reversal and baked-contact tests suggesting a primary origin. The high-quality paleomagnetic pole positioned the EABs at 75.6° ± 6.8° N at ~220 Ma using Beijing as a reference site, which is in good agreement with the paleolatitude resolved from the apparent polar wander path of Eurasia. Along with the ages newly-reported from the “stitching pluton” that intruded the Mongol-Okhotsk suture, our study reveals a full amalgamation between the EABs and Pangea by ~220 Ma, indicating that Pangea comprises ~99% of available continental crust and was perhaps the largest of all known supercontinents.The refined reconstruction of East Asia provides an opportunity to reevaluate the paleogeography and climatic patterns of Pangea. The climate-sensitive lithofacies in East Asia indicate a humid-temperate climate during the Late Triassic and Early Jurassic. The wet conditions were typically explained via a mega-monsoon model. However, according to our new reconstruction, much of the EABs are positioned above ~40° N (within the humid-temperate to subpolar humid zones) during the Late Triassic and early-Middle Jurassic. The humid-temperate conditions are therefore consistent with a zonal climate pattern. To better evaluate climatic patterns of Pangea from a global perspective, we further restore the climate-sensitive lithofacies of the Late Triassic according to our Pangea reconstruction. The distribution of lithofacies is compatible with a zonal climate when Pangea reached its maximum size and optimal equatorial symmetry for developing a monsoon climate, which obviates the need for the Pangean mega-monsoon hypothesis.
Measuring snowfall properties with the open-source Video In Situ Snowfall Sensor
Authors: Maahn Maximilian , Maherndl Nina , Steinke Isabelle
Published: February 2023

We do not know the exact pathways through which ice, liquid, cloud dynamics, and aerosols are interacting in clouds while forming snowfall but the involved processes can be identified by their fingerprints on snow particles. The general shape of individual crystals (dendritic, columns, plates) depends on the temperature and moisture conditions during growth from water vapor deposition. Aggregation can be identified when multiple individual particles are combined into a snowflake. Riming describes the freezing of cloud droplets onto the snow particle and can eventually form graupel. In order to exploit these unique fingerprints of cloud microphysical processes, optical in situ observations are required.The Video In Situ Snowfall Sensor (VISSS) was specifically developed for a campaign in the high Arctic (MOSAiC) to determine particle shape and particle size distributions. Different to other sensors, the VISSS minimizes uncertainties by using two-dimensional high-resolution images, a large measurement volume, and a design limiting the impact of wind. Tracking of particles over multiple frames allows determining fall speed and particle tumbling. The instrument design and software will be released as open-source. Here, we present the design of the instrument, show how particles are detected and tracked and introduce first results from campaigns in the high Arctic (MOSAiC), in the Colorado Rocky Mountains (SAIL), and in and Hyytiälä (Finland).  
The Influence of Climate Change and Human Activities on the Future Air Quality in the Beijing-Tianjin-Hebei Region of China
Authors: Li Dongqing , Wu Qizhong
Published: February 2023

As the Beijing-Tianjin-Hebei (BTH) region of China is one of the key areas with PM2.5 air pollution and various control policies, to project the future air quality in this region under different climate scenarios and emission scenarios is of great significance. Under the comprehensive considering meteorology and anthropogenic emission, the target accessibility of 35 µg/m3 annual mean PM2.5 concentration (the Interim Target-1 by World Health Organization) in 2030, similar to the command of the carbon emissions peak and carbon neutrality, will be analyzed based on the sensitivity experiments. This study explored and quantified the influence of climate change and anthropogenic emission on the future air quality in BTH region under the future climate scenario RCP8.5, RCP4.5, and RCP2.6 with the baseline and reduced emission inventory (Base and EIT1 scenarios). The future air quality research modeling system including global climate model BNU-ESM, regional meteorological model WRF, emission process model SMOKE and air quality model CMAQ is utilized. The BNU-ESM provided the global meteorological field, and the more specific meteorological data simulated by WRF using dynamical downscaling method were adopted to drive the SMOKE model to calculate emission inventory and CMAQ model to generate air pollutant results. The results show that the future PM2.5 concentrations over BTH still present the seasonal variation, higher in winter and lower in summer. Moreover, the annual PM2.5 concentrations under various climate scenarios and under Base emission scenario are almost consistent, about 40µg/m3. However, the annual PM2.5 concentrations over BTH under the identical RCP4.5 climate scenario and under diverse emission scenario shows huge differences. The annual PM2.5 concentrations under EIT1 emission scenario is 37.5% less than the value under Base emission scenario and could achieve the annual target of 35µg/m3. Besides, the shape of high PM2.5 concentrations follows the area with high emission inventory. In a word, the future PM2.5 concentrations over BTH region is highly related to anthropogenic emission by human activities, while the climate change in 2030 has little impact on the future air quality over BTH region. That indicates emission reduction is significantly required to achieve the new Chinese PM2.5 target in 2030.
A Development of High-Resolution Long-Term Gridded Meteorological Data for South Korea using Deep Learning
Authors: Jeong Yookyung , Byun Kyuhyun
Published: February 2023

Climate change has a considerable impact on socioeconomic fields as well as on the natural environment. To effectively respond and adapt to climate change, we should analyze the long-term climate change trends and future impacts according to plausible climate scenarios. For this, the production of high-quality and high-resolution gridded meteorological data based on observation is essential, which is important for developing high-quality downscaled future projections. However, South Korea lacks the long term gridded meteorological data because a dense network from ASOS (Automated Synoptic Observing System) and AWS (Automated Weather System) Stations was available only after 2000. To address this problem, this study aims to produce high quality gridded meteorological data for a historical period (1973-1999), which could have been generated if a dense network existed. Specifically, we reconstruct spatial variations and features of meteorological variables for the historical (1973-1999) period by relating the gridded products for more recent period (2000-21) to that for preceding period (1973-1999) based on a deep learning algorithm. For this, MK-PRISM, an interpolation method for quantifying the effects of meteorological factors based on elevation in South Korea was applied to produce two different version of gridded products based on two different observation networks: a sparse network (ASOS) and a dense network (ASOS+AWS) over the recent 22 years (2000-2021). Then, we develop the Long-Short Term Memory (LSTM) for each grid cell using the gridded products by the sparse network as input and the denser network as output layer. Finally, we generate meteorological variables for the period of 1973-1999 using gridded product by a sparse network as input of the developed LSTM model for each grid cell. Our preliminary results showed that Nash-Sutcliffe Efficiency (NSE) was higher than 0.9 in most grid climate prediction models. Therefore, our development in this study has a potential to calculate high-quality and long-term meteorological data which can be used as important data to analyze the long-term climate trends and variability.Acknowledgement:This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. NRF-2022R1A4A3032838).
Drainage development in an intra-continental mountain belt: A case study from the south-Central Tian Shan
Authors: Gong Lingxiao , van der Beek Peter , Schildgen Taylor , Sobel Edward , Racano Simone
Published: February 2023

As the highest intra-continental orogen in Central Asia, with summits above 7000 m, the Tian Shan orogenic belt has experienced multiple phases of orogeny, and has been reactivated since the early Cenozoic in response to the India-Asia collision. In the south-Central Tian Shan, sedimentary and thermochronology records suggest that Cenozoic deformation initiated from the late Oligocene to the early Miocene, leading to the building of widely-spaced mountain ranges. The Kyrgyz south-Central Tian Shan is characterized by a significant contrast between a longitudinal (i.e., strike-parallel) drainage pattern in the west and a transverse (i.e., strike-perpendicular) drainage in the east. However, it is not clear how the drainage pattern, a key topographic feature in orogenic belts, responded to Cenozoic structural reactivation and uplift of individual ranges.We focus here on the transition area between the regions of longitudinal and transverse drainage: the anomalously large Saryjaz catchment, which drains the highest part of the south-Central Tian Shan and shows a complex and peculiar drainage pattern. Through geomorphic observations and existing geological (i.e., structural and lithological) data, we analyze drainage characteristics, including longitudinal profiles in χ-space, knickpoints, and normalized channel steepness to understand the possible controls on the observed drainage pattern. We discriminate between knickpoints of different origin: tectonic (potentially linked to active faults), lithologic, glacial and linked to transient waves of incision.We find a series of transient knickpoints in tributaries downstream of a sharp U-shaped bend along the main stem of the Saryjaz catchment, which also shows a striking increase in channel steepness. Both observations indicate recent incision along this reach. The incision depth and the elevation of knickpoints both show a decreasing trend downstream. These results suggest that incision is driven “top-down” by a large-magnitude capture event rather than “bottom-up” by a base-level drop. We link this capture to ongoing replacement of the longitudinal drainage system to the west by the transverse one to the east, consistent with inferred patterns of drainage development in other intra-continental mountain belts and suggesting a more mature stage of drainage development in the east.
Marine geological maps as essential seabed geodiversity information for sustainable management
Authors: Dolan Margaret F.J. , Bøe Reidulv , Bjarnadóttir Lilja R.
Published: February 2023

Recently, international focus on the United Nations Sustainable Development Goals has led to the proposal of Essential Geodiversity Variables (EGVs), a framework for geological (geodiversity) information, intended to stand alongside Essential Variables (EVs) already defined for Climate, Biodiversity and Oceans (limited to ocean physics, biochemistry, biology, and ecosystems). In Norway, the Nature Diversity Act, which acknowledges geological and landscape diversity alongside biodiversity, has helped establish geology as part of an essential foundation for knowledge-based management, on land, in the coastal zone and offshore. In keeping with this, geological mapping is a core component of two ongoing national multidisciplinary seabed mapping initiatives [MAREANO, Marine Base Maps for the Coastal Zone (pilot)].Here we examine to what extent marine geological map products from the Geological Survey of Norway generated under these mapping initiatives fit within this EGV framework and how well it is suited to information on marine geodiversity. Further, we examine opportunities for highlighting quantitative geodiversity information through the development of non-traditional marine geological map products. We present some thematic examples at different spatial scales which explore the potential for delivering seabed geodiversity and related geological information more directly. It is important that such information is available in forms that are readily accessible and understandable to a wide range of end users who are largely non-geologists, and that it complements existing information used in coastal and offshore management.  
Quantitative comparison between DInSar-derived surface displacements on slow-moving landslides and ground-based rainfall series
Authors: Ardizzone Francesca , Gariano Stefano Luigi , Volpe Evelina , Antronico Loredana , Coscarelli Roberto , Manunta Michele , Mondini Alessandro Cesare
Published: February 2023

Earth observation data are helpful in analyzing how climate-related variables affect geomorphological processes. This work aims at evaluating the influence of rainfall on slow-moving landslides, by means of a quantitative procedure for (i) identifying clusters of pixels measuring satellite-based surface displacements indicating landslide activity, (ii) comparing them with rainfall series, and (iii) applying statistical tests to assess their relationships at the regional scale. The methodology was developed within the framework of the OT4CLIMA project (Development of Innovative Earth Observation Technologies for the Study of Climate Change and Its Impacts on the Environment), funded by the Italian Ministry of Education, University and Research. The project aimed to develop advanced Earth observation technologies and methodologies for improving the capabilities to understand the effects of climate change at regional and sub-regional scale.The procedure presented here was applied in the Basento river basin, within the Basilicata region, southern Italy.  The Basento catchment, with an area of 1535 km2 and a NW-SE trend, falls within the domain of the Apennine chain in the western part, and within the Bradanic Trough in the eastern part. The stratigraphic and structural setting of the basin plays a significant role in determining landslide occurrence and distribution.Rainfall series were gathered from rain gauges (http://www.centrofunzionalebasilicata.it/it/) and analyzed to evaluate the presence of temporal trends. Ground displacements were obtained by applying the P-SBAS (Parallel Small BAseline Subset) technique to three datasets of Sentinel-1 images: T146 ascending orbit, and T51 and T124 descending orbits, for the period 2015–2020. The displacement series of the pixels located in areas mapped as landslides by the Italian Landslide Inventory (IFFI database, https://idrogeo.isprambiente.it/app/) and sited within rain gauge influence regions (defined as 10 km circular buffers) were studied.Two slow-moving landslides were selected and investigated in detail. The average displacement series of the landslides were analyzed and compared to the rainfall series to search for relations, by employing statistical and non-parametric tests. More in detail, the Kendall rank correlation coefficient and the Maximal Information Coefficient were adopted in the analysis. Significant results were obtained for the T124 descending orbit for both landslides, for a 3-day cumulative rainfall and a 7-day delay of the slope response. Given the procedure’s replicability it can be applied to study areas with different physiographic and climatic features. Other applications might involve satellite- or radar-based rainfall estimates.
Development of an optimized, combined and high-resolution imaging method for the site investigation of radioactive repositories (DOSIS)
Authors: Ding Hui , Scholze Maximilian , Schörner Eva , Sortan Sonia , Hertweck Thomas , Houpt Lars , Bohlen Thomas , Kühne Niklas , Jusri Tomi , Hlousek Felix , Buske Stefan
Published: February 2023

3D seismic measurements are a tool for high-resolution structural exploration of the subsurface using artificially generated seismic waves. Depending on the acquisition geometry and the seismic source, structures can be examined at depths ranging from a few meters to more than 10 km. The accuracy of the geological layer boundaries in the depth image resulting from the field data depends heavily on the quality and the details of the physical earth model and the imaging algorithms used.The "DOSIS" project was initiated in order to design an optimized, combined and high-resolution method to facilitate finding answers for important geophysical and geological questions in the exploration of repository sites in Germany in the future. In the framework of the "DOSIS" project, the simulation of elastic waves using finite differences and the associated full-waveform inversion as well as the Fresnel-volume migration are further developed, so that seismic anisotropy and inelastic attenuation can be taken into account for a detailed characterization of the subsurface. These methods are tested and validated using both, synthetic data and real data in the form of a massive high-quality 3D seismic data set acquired in 2020 in the area of the "Asse" salt structure in Lower Saxony and provided by BGE.
Short- and long-term changes in soil physical properties following biochar addition to soils with different textures
Authors: Zanutel Martin , Garré Sarah , Bielders Charles
Published: February 2023

In the context of global soil degradation, biochar is being promoted as a potential solution to improve soil quality in addition to its carbon sequestration potential. Burying biochar in soils has been shown to affect soil physical properties, but the intensity of this effect depends, among others, on soil properties and application rates. Moreover, the long-term effects of biochar remain largely undocumented yet they are important to quantify given biochar’s persistency in soils. The objective of this study was therefore to determine the short-term and long-term effects of biochar on soil physical properties in function of soil texture and biochar application rates. For this purpose, experiments were conducted in Wallonia (southern Belgium) at two sites with different soil texture (silt loam and sandy loam). Both sites are characterized by the presence of former kiln sites that were used for studying the long-term (> 150 years) effect of hardwood biochar. In addition, fresh biochar produced from Picea abies at 500°C by GreenPoch SA was buried in subplots at both sites at rates of 1% and 2% in mass in the top 10 cm just before the spring sowing in 2021. Samples were collected on September 2021 in kiln sites, in fresh biochar (1 & 2%) subplots and in biochar-free reference plots, in triplicate. The measured soil physical properties were the bulk density, the water retention curve and the hydraulic conductivity curve.Reference subplots were characterized by higher bulk density and lower saturated water content than biochar subplots. The presence of biochar increased the water content for pF < 1.5. These biochar effects were higher for the sandy loam compared to the silt loam and in the short-term compared to the long-term. The plant available water capacity increased with the presence of biochar on the sandy loam, but was unaffected on the silt loam. The hydraulic conductivity was slightly higher for pF < 1.5 in the biochar subplots compared to the reference subplots. On the silt loam, this effect was more visible for fresh biochar whereas on the sandy loam, this effect was higher in the kiln sites. Therefore, the study highlighted a positive effect of biochar in the short-term and in the long-term on soil physical properties for the range of soils and biochar application rates investigated here. Further research may be needed to confirm the observed trends over a wider range of soil types, biochar types and biochar application rates as well as to better understand the underlying mechanisms.
A comparative study of SMAP and ASCAT satellite soil moisture products with cosmic-ray neutron sensing and in-situ data in a Mediterranean setting
Authors: Detsikas Spyridon E. , Petropoulos George P. , Koutsias Nikos , Gasparatos Dionisios , Pisinaras Vasilis , Bogena Heye , Wendland Frank , Herrmann Frank , Panagopoulos Andreas
Published: February 2023

Obtaining Soil Moisture Content (SMC) over large scales is of key importance in several environmental and agricultural applications especially in the context of climate change and transition to digital farming. Remote sensing (RS) has a demonstrated capability in retrieving SMC over large areas with several operational products already available at different spatiotemporal resolutions. At the same time, cosmic-ray neutron sensing is a recently emerged approach in retrieving high temporal resolution SMC at intermediate spatial scales. The present study conducts an intercomparison between different RS-based soil moisture products, daily SMC retrievals from a cosmic-ray neutron sensor (CRNS) station and a network of in situ SoilNet wireless sensors installed at the Pinios Hydrologic Observatory ILTER site in central Greece for a time period of 2018-2019. The RS-based soil moisture products included herein are from NASA’s Soil Moisture Active Passive (SMAP) and Metop-A/B Advanced Scatterometer (ASCAT) satellite missions. The methodological workflow adopted includes standardized validation procedures employing a series of statistical measures to quantify the agreement between the different RS-based soil moisture products, CRNS-based SMC and the SoilNet ground truth data. Our study results contribute towards global efforts aiming at exploiting CRNS data in the context of soil moisture retrievals and their potential synergies with RS-based products. Furthermore, our findings provide valuable insights into assessing the capability of CRNS at retrieving more accurate SMC estimates at arid and semi-arid environments such as those found in the Mediterranean basin, while supporting also ongoing global validation efforts.Keywords: Cosmic Ray Neutron Sensors; SMAP; ASCAT; SoilNet; Soil Moisture Content
Ecosystem services at risk from disturbances in European forests
Authors: Lecina-Diaz Judit , Senf Cornelius , Grünig Marc , Seidl Rupert
Published: February 2023

In Europe, forest ecosystems are facing increasing disturbances such as wildfires, insect-outbreaks and windthrows, and the impacts of such events are likely to increase under ongoing climate change. Increasing disturbances can challenge forest resilience and vulnerability, resulting in higher risks of losing forest ecosystem services. However, quantifying risk across large spatial scales such as Europe is still a fundamental research challenge, since it requires understanding and evaluating the main elements of risk. In this study, we aim to assess the risk of losing forest ecosystem services due to the most common forest disturbances in Europe (wildfires, windthrows and insect-outbreaks – mainly spruce bark beetle). To do so, we mapped the risk components across European forests: exposed values, hazard magnitude, susceptibility and lack of adaptive capacity. Exposed values were quantified in terms of the ecosystem services provided by forests (i.e., timber volume, carbon stocks, soil erosion control, protection against gravitational hazards, and outdoor recreation), that could be lost if the disturbance occurs. The magnitude of the hazard and its probability distribution was quantified using integrative hazard indices (e.g., the Fire Weather Index for wildfires). Susceptibility was based on characteristics that modulate the immediate impacts of the hazard, such as tree height for windthrows or forest continuity for spruce bark beetle. Lack of adaptive capacity was assessed using historical post-disturbance canopy recovery of forests. We integrated and harmonized different indicators, datasets and maps for each risk component and disturbance. Then, we combined the risk components to obtain a risk map for each ecosystem service and disturbance considered, which allowed us to identify the areas with the highest risk. This study is the first ecosystem services’ risk assessment of European forests, which provides critical spatial information for these forests. Given that climate change could amplify forest disturbances, the results of this study could be used to anticipate and adapt to future conditions, as well as to guide efficient forest management.
Hyper-resolution hydrological modelling over Europe: results and emerging challenges
Authors: van Beek Rens , Hoch Jannis , Sutanudjaja Edwin , Wanders Niko , Bierkens Marc
Published: February 2023

Performing hydrological simulations at ‘hyper-resolution’, that is at or below a spatial resolution of 1 km, was and still is a major challenge in hydrological sciences. However, as computational power and the number of readily available and open datasets at useful spatial resolutions increase, several hyper-resolution modelling efforts have been taken. Here, we present a first continental-scale application of the global hydrological model PCR-GLOBWB over Europe at 1 km spatial resolution. To isolate the effect of resolution refinement, results are compared with runs at the thus far ‘default’ resolutions of 10 km and 50 km, respectively. A range of modelled states and fluxes was evaluated against observations: discharge, evaporation, soil moisture, and terrestrial water storage. Evaluation metrics indicate increased accuracy with finer spatial resolutions for simulated discharge. For the other variables, results are mixed possibly due to the coarse resolution of the validation products: while the used validation products have the advantage of long observational records which helps establishing a robust baseline understanding, their spatial resolution may be too coarse to fully assess the accuracy of models at hyper-resolution. At that scale, more recent satellite products can be of more use but at the cost of only short observation record. We thus additionally validated 1 km model output against additional validation products at finer spatial resolution. Furthermore, 1 km output of PCR-GLOBWB is benchmarked against 1 km output over the UK indicating that additional emphasis needs to be put on model parameterization. Despite these outstanding challenges, our findings shows that large-scale hyper-resolution modelling is now feasible and that further pursuing these efforts can eventually lead to more locally-relevant hydrological information and process understanding.
Impact of land use/land cover changes on the urban heat load - a case study for the city of Dubrovnik
Authors: Boras Marijana , Žgela Matej , Herceg Bulić Ivana
Published: February 2023

In this study, land use/land cover changes were examined to investigate their impact on the urban heat load of the City of Dubrovnik in the present and future climate. Dubrovnik is situated in the Mediterranean, which has been referenced as one of the most responsive regions to climate change. Therefore, it is crucial to investigate the effects of different substrates on the heat load and its possible mitigation. Firstly, urban heat load, in the current morphology of the city, is investigated in the present and future climate conditions by using data observed at the local meteorological station and data obtained from regional climate models of the EURO-CORDEX initiative. Also, the urban climate model MUKLIMO_3 is utilized to obtain the spatial distribution of the heat load. Climate indices based on measured data (summer days and tropical nights) show that the heat load has been increasing in the last 50 years. The spatial distribution of the heat load in the City of Dubrovnik in the present climate indicates that the highest heat load is in the public and residential parts of the city. Furthermore, during the nighttime, heat load decreases with a reduction in the density of buildings. Climate indices obtained by simulations of the model MUKLIMO_3 for future climate scenarios (rcp4.5 and rcp8.5) show that the heat load will increase in the entire city domain, with the strongest increase in its urbanized parts. In this study, the impact of modifications in land use/land cover (like changes in the fraction of buildings, impervious surfaces, vegetation and albedo of the roofs) on the heat load are examined. It is demonstrated that these changes will decrease the heat load to some extent. However, the impact is locally limited and significantly smaller than the contribution of global warming. Therefore, land use/land cover changes can mitigate the urban heat load. However, even more comprehensive interventions cannot eliminate the overall increase in the urban heat load due to global warming.   
NH3 spatio-temporal variability over Paris, Mexico and Toronto and its link to PM2.5 during pollution events
Authors: Viatte Camille , Abeed Rimal , Yamanouchi Shoma , Porter William , Safieddine Sarah , Van Damme Martin , Clarisse Lieven , Herrera Beatriz , Grutter Michel , Coheur Pierre-Francois , Strong Kimberly , Clerbaux Cathy
Published: February 2023

Large cities can experience high levels of fine particulate matter (PM2.5) pollution linked to ammonia (NH3) mainly emitted from agricultural activities. Using a combination of PM2.5 and NH3 measurements from in situ instruments, satellite infrared spectrometers, and atmospheric model simulations, we demonstrate the role of atmospheric NH3 and meteorological conditions in pollution events occurring in Paris, Toronto, and Mexico City.Ten years of measurements from the Infrared Atmospheric Sounding Interferometer (IASI) are used to assess the spatio-temporal NH3 variability over and around the three cities. The three regions are subject to long range transport of NH3, as shown using HYSPLIT cluster back-trajectories. The results show that the NH3 variability is mainly driven by meteorology, and interestingly, we can detect the fertilizers application period by looking at the NH3 – temperature relationship. To check how well chemistry transport models perform during pollution events, we evaluate simulations made using the GEOS-Chem model for March 2011. In these simulations we find that NH3 concentrations are overall underestimated, though day-to-day variability is well represented. PM2.5 is generally underestimated over Paris and Mexico, but overestimated over Toronto.We use complementary information derived from IASI, and ground-based open-path measurements over Paris. We, therefore, assess the NH3 temporal variabilities at different timescales (diurnal, seasonal, and interannual), to unravel NH3 sources (agriculture and traffic) in Paris.
Depuration kinetics of TNT and its metabolites in lab exposed blue mussels (Mytilus edulis, L.)
Authors: Binder Franziska , Bünning Tobias , Strehse Jennifer , Maser Edmund , Brenner Matthias
Published: February 2023

Explosive chemicals released by dumped warfare material pose a threat to the marine environment and can enter the marine food web. These chemicals are toxic and are suspected to be carcinogenic, mutagenic and have also genotoxic effects. 2,4,6-Trinitrotoluene (TNT) is one of the most used explosives in munitions and therefore of special interest. To test the potential uptake, bio-concentration or bio-accumulation, and metabolism or depuration of TNT in marine organisms two lab exposure experiments were conducted using common blue mussels (Mytilus edulis). Mussels were exposed to different TNT concentrations for a specific period of time. The first experiment ran for a total of 120 hours, with 48 hours of exposure to different TNT concentrations (0 mg/L, 0.625 mg/L, 1.25 mg/L and 2.5 mg/L) followed by a 72 hours recovery phase in clean artificial seawater. Mussel sampling took place during the recovery phase.The second experiment was performed as follow up to the first experiment and was conducted over 36 hours, with 24 hours of exposure and 12 hours of recovery. Water and mussel samples were taken during exposure and recovery phase with a higher sampling resolution within the first hours of the recovery phase. GC-MS/MS was used to determine the mussel tissue and water concentration of TNT and its metabolites 2-amino-4,6-dinitrotoluol (2-ADNT), 4-amino-2,6-dinitrotoluol (4-ADNT) and 2,4-diamino-6-nitrotoluene (2,4-DANT).Results of the first experiment showed a rapid decrease in TNT and metabolite concentrations in mussel tissues over time. Overall, 57 to 76 % of the detected concentration was metabolised within the first four hours after the exposure. Analysis of samples of the second experiment verified the results from the first experiment showing clear linear digression of the two ADNTs within the first four hours of the recovery phase and a more or less complete metabolism of the parent compound TNT.In summary, uptake of TNT in relation to the exposure concentration could be proven and first insights concerning the metabolism and depuration velocity could be shown.Keywords: TNT, metabolites, 2-ADNT, 4-ADNT, metabolic rate, depuration
Standardized piezometric indicator to improve the evaluation of the aquifer state. Doñana case study (SW Spain)
Authors: Guardiola-Albert Carolina , De Stefano Lucia , Barracaldo Orrego Juan Camilo
Published: February 2023

The Doñana aquifer system (SW Spain) is a coastal alluvial detrital formation composed of sands and gravels of fluvial, deltaic and marine origin. This aquifer is the basis for the sustainability of the water resources of the Doñana Natural Space, which includes the Doñana National Park.From 1991 the water administration initiated a monitoring program of piezometric levels of the Doñana area assuming its direct control, which culminated in 1995 with the establishment of the official control network. In 2021 groundwater monitoring was operational in 261 points distributed throughout the territory of Doñana.To assess the state of the aquifers around Doñana, the water administration uses a quantitative groundwater status index that is calculated from monthly piezometric level readings and requires that the length of the series be long enough to include wet and dry periods. This index has values bounded between 1 and 0. It is based on the comparison of data from the same month of the year. The driest month is used as the reference month.The use of this index to estimate the quantitative status of the Doñana area, however, is criticized by scientists and environmental associations for its lack of statistical basis. There are other definitions of a standardized piezometric indicator based on statistical criteria, like those used for the calculation of the standardized drought index. This standardized piezometric indicator is already used in other countries such as France. The present work proposes to use the standardized piezometric indicator to assess the state of Doñana aquifers and compare the results with the index currently used by the water administration.