bluuebunny/crossref_metadata_2025 huggingface dataset:
Repeating crustal and intermediate-depth earthquakes from the Vrancea seismic region.
Authors: Poiata Natalia , Grecu Bogdan , Tataru Dragos , Borleanu Felix
Published: February 2023

Vrancea seismic zone is the most important seismically active region in Romania, representing the main source of seismic hazard in the area and neighbouring countries. The largest significant earthquakes of the past century, M 7.7 and 7.4 in 1940 and 1977, caused major and widespread destruction. The intermediate-depth earthquakes from Vrancea have a particular space distribution, being constrained to a compact volume (60-180 km in depth and 20x50 km areal extent) and falling into the category of, so called, “seismic nests”, with a peculiar and not well understood seismogenic mechanisms.
We present first results of the repeating events identification for both the crustal and intermediate-depth activity from the Vrancea seismic region, obtained by multi-channel waveform-similarity (cross-correlation - cc) analysis for earthquakes extracted from the ROMPLUS catalogue. The analysed events cover the time-period of about 2.5 years (August 2016 – December 2018) and contains 1229 earthquakes with magnitude of 2.5 – 5.9. Of these events 630 correspond to crustal and 599 – to the intermediate-depth earthquakes. Our analysis identifies 37 families of similar events (cc > 0.7) with the largest one composed of 30 events. We observe that most of the repeating events families are located in the deeper portion of the Vrancea intermediate-depth seismic volume, at the depth greater than 100 km. The identified most active family corresponds to the average depth of 140 km. Most of the intermediate-depth families are characterized by the activity that is persistent in time over the analysed time-period. For the crustal seismicity, we identified over 35 similar event families, most of which corresponding to the short-lived activations of the local (fault) structures.
In the presentation, we will discuss how these results, in relation to the structural composition and tectonic regime of the region, can help to better understand the depth-dependent activity of the Vrancea seismic zone and whether there exists a potential correlation between the crustal and intermediate-depth seismicity.
Assessing Effectiveness of the Tsunami Alert Messages Issued by NEAMTWS-TSPs: a case study from May 2nd, 2020 South Crete Earthquake Tsunami alert for Egypt
Authors: Hassan Hany , Peresan Antonella
Published: February 2023

A tsunami induced by a shallow offshore earthquake of magnitude Mw=6.7 occurred south of the island of Crete (Greece) on May 2nd, 2020. The initial tsunami alert message (TAMs) received by the Egyptian National Tsunami Warning Focal Point for Egypt (i.e. Egyptian National Research Institute of Astronomy and Geophysics-NRIAG) was issued by the Geodynamic Institute of the National Observatory of Athens (NOA-HLNTWC), and was based on preliminary, rather inaccurate hypocenter and magnitude estimates. About 36 minutes after the earthquake, a follow-up message with an increased tsunami warning level was issued; the updated warning was motivated by a significant revision of earthquake source parameters estimates. The later message, however, was issued without taking into account the available observations from sea-level data.
In this study we investigate the effectiveness and usefulness of the TAM messages received by NRIAG for the coastal areas of Egypt (including the issue time and the source parameters on which the messages are based), by cross-checking them against observed and modelled seismological and sea level data. Based on results from the critical review of the tsunami warning messages, disseminated by NOA-HLNTWC and other TSPs in the Eastern Mediterranean Sea and received by NRIAG (which is a TWFP for Egypt), a comprehensive revision of the tsunami early warning system tools and procedures seems urgently needed in the region. The active involvement of countries along the southern coast of the Mediterranean turns out to be crucial, as the analysis shows that tsunami warning can only be efficient with international cooperation on data (seismic and sea level) and procedures.
Simplified Kalman smoother and ensemble Kalman smoother for improvingocean forecasts and reanalyses
Authors: Dong Bo , Haines Keith , Chen Yumeng
Published: February 2023

Dong et al. 2021 presented a post processing smoothing method for application inoperational ocean reanalysis products using the archive of sequential filterincrements. This simple smoother, based on a temporal decay parameter, iscapable of effectively reducing errors in global ocean reanalyses, especially where orwhen no observations are being assimilated (through assessment againstindependent data). Here we further exploit this smoothing method by implementingit in the Kalman filter (KF) and ensemble Kalman filter (EnKF), and comparing it’sperformance with traditional extended Kalman smoother (KS) and ensembleKalman smoother (EnKS) in the Lorenz 1963 model.We demonstrate that our smoothing algorithm is equivalent to the KS and EnKSexcept that the cross-time error covariances in the Kalman smoothers are modifiedas the Kalman filter error covariance multiplied by a cross-time decay term. Thesimplified KS and EnKS provide substantial improvement over the KF and EnKF withsmaller RMSE, while incurring very little computational or additional storage cost,such that there is significant potential of implementing these methods inoperational ocean forecasts and reanalyses.
Simulating Changes in Tropical Cyclone Activity During the Deglaciation
Authors: Tabor Clay , Lofverstrom Marcus , Montañez Isabel , Oster Jessica , Zarzycki Colin
Published: February 2023

How tropical cyclones respond to climate change remains an open question. Due to recent increases in computing power and climate model resolution, it is now possible to explicitly simulate tropical cyclone genesis and life cycle over long temporal and spatial scales. So far, most high-resolution simulations have explored tropical cyclones under present-day and future climate conditions. There has been little work on tropical cyclone activity in past climates. Here, we help fill in this gap with high resolution simulations of the last deglaciation including the Last Glacial Maximum (LGM; 21-ka), Heinrich Stadial 1 (HS1; 16-ka), and Preindustrial (PI; 1850 CE). We use the water isotope tracer enabled version of the Community Earth System Model version 1.3 (iCESM1.3) at ~0.25° horizontal resolution to simulate climate and the TempestExtremes algorithm to track tropical cyclone features. Our preliminary results show intriguing spatial changes in tropical cyclone activity at the LGM relative to PI. The Atlantic and Indian basins produce less tropical cyclones while the Western Pacific produces more tropical cyclones at the LGM. Furthermore, tropical cyclone frequency decreases in the southern hemisphere but remains similar in the northern hemisphere. The LGM simulation also produces fewer strong storms (greater than 49 m/s). Further investigation will explore the physical mechanisms for the simulated tropical cyclone responses during the deglaciation as well as the effects of freshwater flux into the North Atlantic on tropical cyclone activity.
Martian atmospheric chemistry of HCl: implications for the lifetime of atmospheric methane
Authors: Taysum Benjamin M. , Palmer Paul I. , Luginin Mikhail , Ignatiev Nikolay , Trokhimovskiy Alexander , Shakun Alexey , Grigoriev Alexey , Montmessin Franck , Korablev Oleg , Olsen Kevin
Published: February 2023

We develop a 1-D atmospheric photochemistry model for Mars to interpret hydrogen chloride (HCl) profile measurements collected by the ACS MIR spectrometer aboard the ExoMars Trace Gas Orbiter (TGO) in Mars Year (MY) 34. We include a gas-phase chlorine chemistry scheme and study 1) surface chemistry, 2) hydrolysis, 3) photolysis, and 4) hydration and photolysis of dust grains as possible sources of gas-phase chlorine chemistry. Heterogeneous uptake of chlorine species onto water ice and minerals in Martian dust are loss processes common to all mechanisms. We drive the 1-D model using TGO profile measurements of aerosols and water vapour. We find that mechanism four can reproduce observed HCl profile tendencies during MY34. It reproduces the HCl cut-off at high southern latitudes (<60° S) at ≈35 km, and forms layers of HCl between 20-35km at the tropics. Mechanisms one, two, and three result in significant model biases.Seasonal variations of Martian HCl are reproduced by mechanism four, yielding low HCl abundances (< 1 ppb) prior to the dust season that rise to 2--6 ppb in southern latitudes during the dust season. We find that the additional Cl atoms released via mechanism four shortens the atmospheric lifetime of methane by a magnitude of 102. This suggests the production of Cl via the UV (or other electromagnetic radiation) induced breakdown of hydrated perchlorate in airborne Martian dust, consistent with observed profiles of HCl, helps reconcile observed variations of methane with photochemical models.
Dirty Matters: The Soil Game
Authors: Burak Emma , Christina Van Midden Christina
Published: February 2023

The presenters would like to showcase a game they have created through funding allocated by the British Society of Soil science. The original brief of the project was to demonstrate the ability of soils to deliver on the UN Sustainable Development Goals, specifically Zero Hunger, Clean Water and Climate Action. We also wanted to capture the interlinking complexity of soil in a simple, fun, and educational format in order to promote how amazingly intricate and fascinating soils are.The resulting game is called Dirty Matters: The Soil Game and focuses on how soil management practises affect soil, which in turn affect the SDGs. Dirty matters is a fully cooperative game where the players embody soil organisms (including the mole, earthworm, and mycorrhizal fungi) and move around the soil implementing soil management techniques (such as cover crops, no tillage regimes, and adding manure) to counteract the events that negatively impact the soil (such as soil compaction, acid rain, and erosion). This is all done with the overarching aim of keeping the soil healthy enough to meet the yield requirements of a growing population whilst trying to avoid polluting water and excessive carbon loss.The process of making this boardgame initially involved brainstorming sessions to form a game design and then rigorous research to make sure our concepts were backed by up-to-date science. Once a playable game design was achieved, we started play testing with other soil scientists and a variety of other communities to make sure both the mechanics and science worked, tweaking the game after each session to incorporate feedback. The final stages included making it look appealing by engaging with a graphic designer. As of today, Dirty Matters is free to download and printer friendly educational tool to advance the understanding of soil and how we should take care of it and everything in it.
Analysis of Uncertainty Due to Climate Change Using REA Approach in Different Rivers of Western Ghats, South India
Authors: Chandu Navya , Eldho Thekkilakkattu Iype
Published: February 2023

The appraisal of climate change impacts on river hydrology using different Global Climate Models (GCM) and emission scenarios is incomplete, without quantifying the uncertainty associated with it. It is critical to quantify those uncertainties in order to develop beneficial managerial capabilities. The objective of the present study is to model the GCM and scenario uncertainty in Western Ghats (WG) river basins of South India using Reliability Ensemble Average (REA) for the estimation of stream flows. The analysis is carried out grid wise, for monsoon (JJAS) rainfall in near future (2011-2040). The statistically downscaled (kernel regression) rainfall data at 0.25o resolution for three CMIP-6 GCMs CNRM, CCCMA and MPILR for SSP2 4.5 and SSP5 8.5 are used in the present study. The river basins Netravati, (upper region), Kadalundi (middle region) and Manimala (lower region) in different elevation profile (lowland, midland and ghats) of WG are chosen as a criterion for quantifying the uncertainty associated with GCM models and emission scenarios. The uncertainty associated with GCM is found to be more significant than the scenario uncertainty in this region. The GCM model shows good correlation with the latitude profile in WG. The GCM MPILR have higher weightage in lower and middle region as compared to the others while the GCM CNRM is less pronounced in the high elevation zones along the basin.Keywords: Climate Change, Variable Infiltration Capacity Model, Uncertainty, REA approach.
Permanent Displacement Distribution From Strong Ground Motion Records of the 2023 Mw7.7 Earthquake.
Authors: Adanır Emrecan , Tanırcan Gülüm
Published: February 2023

One of the most damaging earthquake effects occurring in the vicinity of the fault trace is fling step, also known as permanent displacement. However, due to the fact that the standard filtering techniques eliminate the low frequency portions of the motion, the permanent displacements are not seen on the displacement time histories derived from the accelerogram records. Thus, fling step is neglected in many engineering practices. To reveal the permanent displacements, special data processing schemes based on removal of the baseline shifts in separated time windows were proposed. In this study, the most recently proposed data processing scheme eBASCO (Schiappapietra et al., 2021) is improved and the effectiveness of the new scheme is tested by comparing the obtained displacements on the processed records with those derived from nearby GPS data for 25 records from worldwide earthquakes. Preliminary site screening efforts and geodetic observations demonstrated that the earthquake sequence of February 6, 2023 in Turkey caused remarkable permanent displacements, which might be one of the reasons for severe damage and collapse of the structures, especially those which have long fundamental periods such as pipelines, roadways and high-rise buildings. In this study, near fault records of the earthquake sequence are processed with the proposed scheme and the obtained permanent displacements are evaluated with those predicted by existing models.
Less than expected? Landslides triggered by the 2023 Mw 7.7 and 7.6 Kahramanmaras (Türkiye) earthquake sequence
Authors: Gorum Tolga , Tanyas Hakan
Published: February 2023

A devastating earthquake sequence occurred on February 6, 2023, within the East Anatolian fault system. Two main shocks, the Mw 7.7 Sofalaca-Şehitkamil-Gaziantep, and Mw 7.6 Ekinözü-Kahramanmaraş earthquakes occurred nine hours apart and affected 10 cities and more than an area of 100,000 km2 (PGA>0.08g). The earthquake-affected area mainly exhibits arid/semi-arid climatic conditions where approximately 15% of the landscape is characterized by steep topography (slope steepness>20°). Initial estimates of globally available predictive landslide models indicated extensive landslide distribution over the area.We examined high-resolution satellite images and aerial photos to provide a better insight into this co-seismic landslide event and its possible post-seismic consequences. These observations are going to be validated and enriched by detailed field surveys. This research presents our preliminary findings as a result of these investigations. Our observations carried out in the first two weeks after the sequence showed that rock fall and lateral spreading are the dominant landslide types, and the overall landslide population could be less than expected. Therefore, the resultant co-seismic landslide event seems unexpected, given the intensity of ground shaking and landscape characteristics. Based on the preliminary investigations, lithology, topographic relief, and climatic conditions appear to be the main variables causing these below expectations for landslide distribution. We should stress that our historical records mostly lack landslide events in arid/semi-arid conditions, as we observed in this event. In this context, this event is going to be recorded as one of a few of its kind. Our observations also showed intense ground shaking and strongly deformed numbers of hillslopes, although most have not failed yet. In particular, heavy rain and snowmelt may result in a considerable number of failures on those hillslopes that are prone to cracking and deformation due to strong ground shaking. In this respect, this area needs to be monitored for a long time to understand the earthquake legacy effect and post-seismic hillslope response.
Mapping the ruptures of the Mw7.8 and Mw7.7 Turkey-Syria Earthquakes using optical offset tracking with Sentinel-2 images
Authors: Provost Floriane , Van der Woerd Jérôme , Malet Jean-Philippe , Maggi Alessia , Klinger Yann , Michéa David , Pointal Elisabeth , Pacini Fabrizio
Published: February 2023

Monday February 6, 2023, two large Mw7+ earthquakes struck Turkey and North-Syria. The first event occurred along the N60 striking East Anatolian Fault (EAF) and its prolongation towards the Dead Sea Fault, the N25 striking Karazu fault, with an epicenter 30 km south-east off the main rupture zone. The second event is located to the north of the first one, along the N100 Sürgü-Çartak fault. Focal mechanisms of both shocks exhibit a dominant left-lateral strike-slip component on sub-vertical faults. These ruptures and mechanisms are compatible with Anatolia westward extrusion between the North and East Anatolian faults in response to Arabia-Eurasia convergence. The complex geometry of the activated faults during this earthquake sequence sheds light on how strain is partitioned and distributed among the faults of this triple-junctions linking Nubia, Arabia and Anatolia.The current constellation of Earth Observation satellites allowed for rapid acquisition of the whole impacted area shortly after the mainshocks. On February 9, 2023, the Copernicus Sentinel-2 satellite captured a set of optical images while the region was mostly cloud free. This dataset offers a complete coverage of the system of faults activated during these events at 10 m spatial resolution. Although this resolution is not sufficient to map surface ruptures directly from the images, image correlation (also known as offset tracking) techniques can be applied on these images to retrieve the distribution of the surface displacement. In the present work, we used the GDM-OPT-ETQ service of the ForM@Ter solid Earth data hub to measure (with the open source photogrammetry library MicMac) the co-seismic displacement between images of January 25, 2023 and February 9, 2023. The massive processing was performed on the Geohazards Exploitation Platform (GEP). The final products of the processing are East-West and North-South displacement maps covering an area of  300 km x 300 km at 10 m resolution and further 2D strain maps are also derived. Spatial offsets in the range of 3 to near 10 m are identified with large geographic variability along the faults. These maps significantly contribute to identify and map the ruptures of the Turkey-Syria earthquakes and determine the along fault displacement. The spatial distribution of the displacement will be discussed together with a first order cluster analysis of the seismic sequence using an aftershock catalogs. The combined datasets should allow us to better understand the complexity of the on-fault and off-fault deformation pattern.
Comparison between the uncertainty in the tsunami forecast from slip models obtained from geophysical data inversion and by a Phase Variation Method
Authors: Romano Fabrizio , Catalan Patricio , Lorito Stefano , Cipriano Escalante Sanchez , Atzori Simone , Lay Thorne , Tonini Roberto , Volpe Manuela , Piatanesi Alessio , Jorge Macias Sanchez , Manuel J Castro Diaz
Published: February 2023

Subduction zones are the most seismically active regions in the world and hosted many great tsunamigenic earthquakes in the past, often with destructive coastal consequences. Hence, an accurate estimate of the tsunami forecast is crucial in Tsunami Early Warning Systems (TEWS) framework. However, the inherent uncertainties associated with the tsunami source estimation in real-time make tsunami forecasting challenging. In this study, we consider the South American subduction zone, where in the last 15 years occurred, three M8+ tsunamigenic earthquakes; in particular, we focus on the 2014 Mw 8.1 Iquique event.Here, we evaluate the variability of the tsunami forecasting for the Chilean coast as resulting i) from the coseismic slip model obtained by geophysical data inversion and ii) from an expeditious method for the tsunami source estimation, based on an extension of the well-known spectral approach. In the former method, we estimate the slip distribution of the 2014 Iquique earthquake by jointly inverting tsunami (DARTs and tide-gauges) and GPS data; we adopt a 3D fault geometry and Green’s functions approach.On the other hand, a set of stochastic slip models in the latter is generated through a Phase Variation Method (PVM), where realizations are obtained from both the wavenumber and phase spectra of the source.In the analysis, we also evaluate how the different physics complexity included in the tsunami modelling (e.g. by including dispersion or not) can be mapped into the tsunami forecasting uncertainty. Finally, as an independent check, we compare the predicted deformation field from the slip models (inverted or by PVM) with the RADARSAT-2 InSAR data. 
Extending aquifer lifespans with pumping reductions: Experiences from the High Plains aquifer
Authors: Butler James
Published: February 2023

The High Plains aquifer in the central United States is one of the world’s largest and most important regional aquifers in terms of the agricultural production that its waters support. The portion of the aquifer in the state of Kansas has been heavily stressed for decades, producing large water-level declines that have called into question the continued viability of groundwater-based irrigated agriculture and the rural communities that depend on it. Given the sparsity of surface water in the region, reductions in pumping, which are typically accompanied by modifications of agricultural practices, are often the only option to extend the aquifer lifespan. Such reductions, however, must be implemented over a relatively large area to make a signiﬁcant impact on regional decline rates. In 2012, the Kansas Legislature approved a new groundwater management option to facilitate pumping reductions, the Local Enhanced Management Area (LEMA) program. This program allows the development of locally generated management plans that are then supported by regulatory oversight. The first LEMA, the Sheridan-6 (SD-6) LEMA, was established in 2013 in a 255 square kilometer area in northwest Kansas with the goal of reducing water use by 20% relative to the prior average use. In the first decade, the pumping reduction was close to 30% after controlling for climatic conditions. More importantly, the water-level decline rate decreased by over 50%, thereby extending the aquifer lifespan by over five years during the first ten years of the LEMA. The ultimate extension of the aquifer lifespan, which will likely be much greater, depends on how net inflow changes with time. Until now, net inflow has remained close to the pre-reduction level. Eventually, however, it will decrease in response to the pumping reductions. Continued monitoring will enable the timing and magnitude of that decrease to be quantified. The success of the SD-6 LEMA has led to the establishment of larger LEMAs in 2018 (12,623 square kilometers) and 2021 (663 square kilometers) with an additional LEMA under consideration. If the success of the irrigators in the SD-6 LEMA can be duplicated in these larger areas, the lifespan of the High Plains aquifer in Kansas will be significantly extended.
Subsurface drip fertigation estimation tool (SubFerT)
Authors: Callau-Beyer Ana Claudia , Mburu Martin , Weßler Caspar-Friedrich , Stützel Hartmut
Published: February 2023

Irrigation and fertilization are essential to increasing crop yield and affect vegetable production and food security. Conventional irrigation and fertilizer application methods often exceed the crop requirements. Moreover, nitrate pollution of groundwater from agriculture is caused by the asynchrony between nutrient availability and crop demand and is an issue of major concern in many regions. As water and nutrients limitations will be more frequent in the coming decades due to climate change along with regulations aiming at protecting water resources, there is a need for innovations in agricultural production to improve water and nutrient use efficiencies. Subsurface drip fertigation (SDF) is the fertigation (irrigation combined with application of dissolved fertilizer) of crops through buried driplines which include built-in emitters to drip water to the surrounding soil. This allows placing the water and fertilizers directly into a small soil volume in the rooting zone at just the rates needed by the plants. SDF systems have a great potential to minimize the movement of water and nutrients below the root zone when effectively managed. Through the combined application of nutrients and water, drought and nutrient stresses can be diminished and yield potentials optimized. SDF systems can therefore make cropping systems not only more environmentally friendly and sustainable, but also more resilient to climatic fluctuations.The aim of our research is to contribute to the understanding of crop growth under SDF. The work presented here is the Subsurface Drip Fertigation Estimation Tool (SubFerT) which is available for farmers who want to integrate this fertigation system in their production. The tool is based on daily water and nitrogen balances at the field scale by modeling (a) crop growth and nitrogen uptake; (b) crop water requirements though daily ET0 estimation using the Penman–Monteith equation, separation between evaporation and transpiration (dual Kc approach); (c) dynamics of water (irrigation, precipitation, root uptake, losses) and nitrogen (mineralization, denitrification, leaching) in the soil root zone. SubFerT-tool provides information on when and how much water and fertilizer to apply to crops grown under SDF system. This tool allows farmers to manage the fertigation of the crops under SDF in an efficient way. Additionally, the tool delivers daily time series of different variables involved in the balance: soil moisture, root uptake, deep percolation, total met transpiration, etc.
FRYv2.0 : a global fire patch morphology database from FireCCI51 and MCD64A
Authors: Mouillot Florent , Chen Wentao , Campagnolo Manuel , Ciais Philippe
Published: February 2023

The assessment of global burned area from remote sensing is an essential climate variable driving land surface GHG emissions and energy/water budget. Gridded 0.25° or 0.5° monthly burned area have been largely used for biosphere/atmosphere interactions modelling, while recent fire/weather analysis or model developments increasingly request fire events, defined as a fire patch with intrinsic fire spread properties. Pixel level information, the finest resolution from global burned area, defined by their burn date, can be aggregated within a spatio-temporal threshold and delineate these fire events. Uncertainties in burn date, the coarse resolution of pixel resolution, multiple ignition points, or the specified values in spatio-temporal thresholds can however lead to various final fire event delineation. Currently, three major global fire event database exist (FRY, Fire Atlas, GlobFire), mostly derived from MCD64A1 pixel level 500m-resolution burned area. We propose here a new version of FRY, based on MCD64A1 and FireCCI51 at 250m, with an updated pixel aggregation method allowing for single ignition fire patches. Fire patch morphology indicators as elongation, direction, complexity have been conserved from v1.0, with additional information as ignition points from minimum burn date from burned area and more timely-accurate hotspots (VIIRS and MCD14ML), rate of spread, fire Radiative power and burn severity, as well as fraction of land cover affected, based on user requirements. The dataset is delivered as a yearly shapefile, with an attribute table referencing all information on ignition, spread and final shape. Global comparison of major information from FRYv2.0 (fire size distribution, fire number, ROS) will illustrate the effects of increasing spatial resolution and better timing from hotspots provided in this new version, freely available for the scientific community for the period 2001-2020.
Five years of real time hydro-meteorological forecasts and monitoring for local civil protection: the SOL and MOCAP warning systems
Authors: Ceppi Alessandro , Gambini Enrico , Ravazzani Giovanni , Lombardi Gabriele , Meucci Stefania , Mancini Marco
Published: February 2023

Among the natural disasters floods are identified with the greatest impact on highly urbanized areas in economic terms and loss of human lives. Flooding phenomena are more often observed due not only to significant weather events, but also to less intense, but more frequent episodes that undermine the urban drainage system and its interconnections with the river network.In this context, an alert system has been developed to predict possible river floods for the Seveso, Olona and Lambro rivers (SOL) 24 - 36 hours in advance with a technology based on the sequential functioning of hydrological meteorological, hydraulic engineering calculation models, and visualization on web-GIS.The proposed flood warning system is, in fact, composed of a physically based and spatially distributed hydrological model for the rainfall-runoff transformation, fed by both observed and forecasted atmospheric forcings of various deterministic and probabilistic meteorological models such as the GFS, Bolam, Moloch, Cosmo I2 and I5, Cosmo-Leps, and WRF.The data measured on the ground are daily provided by a citizen scientist observation network of the Meteonetwork association and by the official Arpa Lombardia network.In recent years, this decision support system has also been integrated with a real-time hydrological monitoring and alert network (MoCAP, an Italian acronym which stands for municipal monitoring for flood alerts), developed for the civil protection of the Bovisio-Masciago town, which is located along the Seveso River.This study describes the benchmark analysis of the coupled forecasting and monitoring systems for local civil protection purposes and its relative performance in the last five years (2018-2022) of functioning.
Research on the Mechanism of Induced Seismicity Utilizing InSAR-Retrieved Land Subsidence, Source Model, and Geological Constraints
Authors: Witkowski Wojciech , Łucka Magdalena , Sudhaus Henriette , Barańska Anna , Hejmanowski Ryszard , Guzy Artur
Published: February 2023

Mining-induced sub-surface rock-failure processes cause seismicity and permanent surface deformation that may result in infrastructural damages and endanger residents in the affected areas. In recent years, this issue has received increasing attention due to the suddenness of the occurrence, the lack of effective predictive capabilities and the adverse consequences.  Importantly, seismic events have caused significant land subsidence and several fatalities in Polish underground mines. To better investigate such mining-induced sub-surface rock failure processes, we analyze rock deformation based on surface displacement data and also put local geology in context with seismological analysis results.In Poland's Legnica-Glogow Copper District, between 2016 and 2020, 13 mining-induced earthquakes in the moment magnitude range from 3.2 to 3.8 have been recorded by the IS-EPOS platform. Based on co-seismic Sentinel-1 satellite radar images of ESA’s Copernicus program, and radar interferometry (InSAR) we measure the surface displacements caused by nine of these earthquakes. The maximum line-of-sight surface displacements are observed for the Mw3.6 mining-induced earthquake on October 17, 2016 with 144 mm and 124 mm away from the satellite in ascending and descending radar interferograms, respectively, and an estimated maximum land subsidence reaching -142 mm. We estimate the location and volume component associated with these surface effects by using an isotropic volume point-source model in a Bayesian inference. The Geodetic Bayesian Inversion Software GBIS has been applied for these calculations. Notably, only some of the earthquakes we analyse resulted in land subsidence. Although no significant relationship between earthquake magnitude and land subsidence is apparent, we find that the greater the thickness of loose Quaternary strata, the greater the land subsidence. The focal points of the deformation at depth of the investigated earthquakes, which we compare to seismic hypocenters, are located at depths of 437 m to 669 m, according to our results. Importantly, these focal points are located above the mining exploitation fields, within layers of rigid Triassic rock. Our results also show a mismatch between the spatial location of the earthquake epicentres and the maximum land subsidence. These differences are up to 440 m and are greater for the earthquake epicentres determined using seismic data than for the source point model. This discrepancy suggests that the epicentre of a mining-induced earthquake is not necessarily associated with the region of maximum rock layer compaction.This study adds to our understanding of the impact of mining-induced seismicity on the occurrence of land subsidence and the seismic mechanism in areas of active mining paving the way towards more sustainable mineral extraction.
Geologic and geomorphic setting control of water sources and flow paths in mountainous headwater catchments
Authors: Segura Catalina , Perry Zachary , Ortega Melendez Jaime
Published: February 2023

Communities downstream from mountainous regions rely on snowmelt for water supply. As climate change reduces the reliability of the snowpack in these regions it is important to understand how and when rain and melt water are stored and released as runoff. In mountainous regions the prediction of water movement is especially complex because water storage capacity and overall water input magnitude and form vary over short distances given variable geology, geomorphology, and topography. We used water stable isotopes (WSI) and water chemistry (ions and cations) to investigate seasonal water sources and contributions in a 64 km2 headwater mountain catchment in Oregon (USA). In one study, we collected > 1,000 synoptic samples between 2021 and 2022 across different seasons in 12 headwater streams (600–1,200 m in elevation and drainage areas 0.1–5 km2) and analyzed them for WSI. Results demonstrate that despite season there are localized variations in WSI within less than 1-km2 between catchments underlain by similar geology but characterized by different geomorphic history of mass wasting events (landslides and earthflows). We also observed weak relationships between elevation and WSI in some streams suggesting that their sources of baseflow are not directly controlled by seasonal precipitation but by differences in storage over spatially variability geomorphic history.  In a second study, we investigated relative streamflow contributions from five tributaries (0.7–17 km2) over the whole year based on weekly WSI and water chemistry in grab and precipitation samples. We found strong differences across streams; the most interesting was a spring-fed stream, whose water contribution varies widely throughout the year, resembling a snowmelt system (with high relative water input in the summer). The depleted WSI signal and relatively high cations concentrations of this stream reveals higher elevation snowfall is moving to the stream through relatively long flow paths. This stream is underlain by porous lava flows demonstrating a strong geologic control on runoff generation. The contribution of this stream to the whole watershed is over 27 times larger in the summer compared to any other season. This finding challenges the idea of streamflow scaling with drainage area because the effective drainage area of this stream varies between 0.8 and 47 km2 while the topographic derived drainage area is 0.7 km2.
Dimensionless Illustration: The Grain Size 2 mm Is Indeed “Special” in the Context of Fluvial Sediment Transport and Morphology
Authors: Parker Gary , An Chenge , Lamb Michael , Garcia Marcelo
Published: February 2023

Long rivers extending from the mountains to the sea often undergo a transition from gravel-bed to sand-bed. The grain size dividing “gravel” and “sand”, i.e. 2 mm, has, on an empirical basis, played a special role in fluvial sediment transport and morphology. Sand-bed rivers and gravel-bed rivers have traditionally been treated separately in terms of morphology and sediment transport. For example, the sediment transport relation of Wilcock and Crowe (2003) treats gravel transport as a function of sand content in the bed. While sand is easily suspended in rivers, there are only sparse records of gravel traveling in suspension under purely fluvial conditions (as opposed to debris flows), and these records become vanishing as grain size increases. Here we study the reason for this in terms of sediment entrainment into suspension from the bed. Garcia and Parker (1991) developed a relation for the rate of suspension of sand from an alluvial, non-cohesive bed. This relation was developed exclusively based on empirical data for sand beds. When the relation is extrapolated to gravel beds, it is found to predict copious suspension where there should be none. The key parameter controlling this is a particle Reynolds number, Rep = (RgD)1/2D/n, where D is grain size, n is fluid kinematic viscosity, R is particle submerged specific gravity and g is gravitational acceleration. However, in the case of spheres, there is a unique relation between particle Reynolds number and dimensionless fall velocity Rf = vs/(RgD)1/2. The Garcia-Parker relation can easily be cast in terms of Rf rather than Rep over the range of sand grain sizes used in the derivation. The curve of Rf versus Rep, however, shows a monotonically increasing zone for small Rep but an approximate plateau region for larger values of Rep. The transitional range between the monotonically increasing and plateau region is Rep = 360 to 600. In the case of quartz in 20° water on Earth, this corresponds to the range 2.0 – 2.8 mm. In the plateau region, the modified Garcia-Parker relation is found to predict negligible suspension of sediment (gravel) within the range of shear velocities most commonly found in rivers. Suspension of gravel is not in principle precluded by the relation, but the conditions commonly found on Earth during floods, even megafloods, do not seem to allow it (Larsen and Lamb, 2016). The result is further verified using the relation for entrainment into suspension by deLeeuw et al. (2020). The results have significance for the interpretation of such phenomena as downstream fining in rivers and gravel-sand transitions. The dimensionless form of the result allows for straightforward modification to the case of ice clasts in liquid methane at the gravitational acceleration. 
Long-term effects of softwood biochars on boreal soils: results from two experiments through 13 years on soils, nutrient cycling and crops
Authors: Tammeorg Priit , Kalu Subin , Karhu Kristiina , Simojoki Asko
Published: February 2023

Biochars have notable potential in sequestering atmospheric carbon over long terms and offer various agricultural and environmental co-benefits. However, there is limited information about the long-term effects of added biochars, as there are only handful of continuously monitored biochar field experiments expanding over a decade, and especially poorly have been studied the long-term effects from boreal regions. The soils in northern colder boreal regions typically have higher carbon content and undergo continuous freeze-thaw cycles. Therefore, effects of biochars in these regions may differ from those observed in warmer climates.We studied the effects of a single application of softwood biochars on two contrasting boreal agricultural soils (nutrient-poor, coarse textured Umbrisol and fertile, fine-textured Stagnosol), both with high initial soil organic carbon contents, over 13 years following the application in 2010 or 2011. We focused on plant yield formation as well as nutrient uptake dynamics of all major Finnish field crops, as well as on soil physical properties and greenhouse gas emissions.We found that the ability of biochar to enhance the supply of nutrients to plants and hence to improve the crop biomass yield exists in boreal conditions, although these effects were minimal and not consistent over the years. Biochar notably increased plant K content, and reduced the plant content and uptake of Al and Na in several years in Stagnosol. The relative plant contents of Cd and Ni in Umbrisol, and P, K, Mg, S, Al, Cu, Fe and Ni in Stagnosol increased over the years. Despite these increased plant contents, no significant improvement was observed in crop biomass yield by added biochar over the first eight years.The enhanced plant available water and reduced bulk density previously reported during the initial years were faded in long-term, likely due to dilution of biochar concentration in topsoil. However, the potential of biochar to affect N2O emission persisted, even seven years after the application, this contributed to reduced yield-normalized non-CO2 GHG emissions. In the presentation, we will share also the preliminary results for the latest growing seasons 2019–2022.
Waves upstream of interplanetary shocks
Authors: Blanco-Cano Xochitl , Trotta Domenico , Hietala Heli , Kajdic Primoz , Rojas-Castillo Diana , Dimmock Andrew , Horbury Tim , Vainio Rami , Jian Lan
Published: February 2023

Interplanetary (IP) shocks can be driven in the solar wind by fast coronal mass ejections and by the interaction of fast solar wind with slow streams of plasma. These shocks can be preceded by extended waves and suprathermal ion foreshocks. Shocks characteristics as well as the level of wave activity near them change as they propagate through the heliosphere and this can impact particle acceleration, and modify the ambient solar wind. In this work we study IP shock evolution and the wave modes upstream of them using a multispacecraft approach with data of Solar Orbiter, STEREO, Parker Solar Probe and Wind. We find that upstream regions can be permeated by whistler waves (f ~ 1 Hz) and/or ultra low frequency (ULF) right-handed waves (f~10-2–10-1 Hz). While whistlers appear to be generated at the shock, the origin of ULF waves is most probably associated with local kinetic ion instabilities. In contrast with planetary bow shocks, most IP shocks have a small Mach number (<4) and most of the upstream waves studied here are mainly transverse and steepening rarely occurs. 
The eruption of the Hunga Tonga-Hunga Ha'apai volcano on 15 January 2022 as observed at seismic stations in Germany
Authors: Plenefisch Thomas , Steinberg Andreas , Hupe Patrick , Pilger Christoph , Donner Stefanie , Gaebler Peter , Ross Ole , Ceranna Lars
Published: February 2023

On 15 January 2022 at 04:15 UTC, an enormous explosive eruption of the Hunga Tonga-Hunga Haʻapai submarine volcano (short: Hunga) occurred in the Tonga-Kermadec volcanic area in the southern Pacific Ocean. It was one of the strongest volcanic eruption within the last 150 years. The eruption column reached a height of more than 50 kilometres causing heavy atmospheric turbulences. A strong Lamb and a tsunami wave were generated. Besides these phenomena also seismic waves could be observed on seismic stations all over the world.Consequently, seismic body and surface waves of the Hunga main explosion could be clearly recorded at seismic stations in Germany. After about 19 minutes, the PKP phase was the first arriving body wave reaching the broadband stations of the German Regional Seismic Network and the Gräfenberg Array. Using the short-period WWSSN-SP filter it was possible to determine the onset times of relatively weak PKPbc phases at several stations. The onset times as well as slowness and azimuth determined by array methods allowed an unambiguous assignment to the Hunga event and an epicenter localization deviating approximately 1 to 1.5 degrees from the volcano.While the PKP phase is only weakly visible in short periods it shows up clearly in the long-period range (SRO-LP filter). The onset times determined therein were still accurate enough to provide a localization similar to that obtained in the short-period range. Furthermore, at least one additional event is detected on the long-period seismograms about 4 minutes after the main event.To assign a seismic magnitude to the Hunga event, we analyzed the surface wave trains. The Ms magnitudes vary between 5.8 and 6.3 within the individual stations of the GRSN, with a mean value of 6.0.The Tonga-Kermadec subduction zone is characterized by strong earthquake activity. This allows us to compare the seismic recordings of the Hunga event with those of earthquakes from the same area with shallow focal depths and comparable magnitudes. It turns out that PKP phases of the Hunga eruption have significantly smaller amplitudes in the short-period range than for the compared earthquakes but similarly strong in the long-period range. We conclude that a long-period excitation is characteristic for the seismically relevant focal process of the Hunga event.
Methane Emissions Across a Diverse Set of Large Landfills in the United States and Canada
Authors: Cusworth Daniel , Duren Riley , Ayasse Alana , Thorpe Andrew
Published: February 2023

Methane emissions from the waste sector may represent a significant fraction of the global anthropogenic methane budget. However, few comprehensive studies across the broad landscape of waste operations exist to validate existing bottom-up models that underpin reporting programs and national inventories. In this study, we flew two airborne imaging spectrometers to map emissions at large landfills across 18 states in the U.S. and three provinces in Canada between 2016-2022. This technology is particularly sensitive to point source methane emissions and can geolocate source locations to within several meters. We observed point sources at a high fraction (52%) of sites and observed high emission persistence (60%), or point source detection frequency, at sites we surveyed multiple times. Airborne derived emissions correlate poorly with EPA reported emission and are on average higher, which could point to some issues with models that underpin reporting protocols. We validated imaging spectrometer aerial emission rates against the Scientific Aviation mass balance technique at 15 landfills, and find good agreement between these two independent measurement systems. Sustained measurements across many landfills and waste sites are needed to validate inventories and provide actionable data for industry operators and enforcement agencies.