bluuebunny/crossref_metadata_2025 huggingface dataset:
Modelling organic carbon content of southwestern German soils using visible near-infrared reflectance spectra and multi-temporal Sentinel-2 data
Authors: Blaschek Michael , Torney Larissa , Frei Michaela , Rückamp Daniel , Chabrillat Sabine
Published: February 2023

The sustainable management of agricultural land requires reliable information about soil physical and chemical properties. Among these properties, soil organic carbon (SOC) is a key attribute, as it serves as an important indicator for soil health and helps fighting climate change through carbon storage in soils. Since direct measurements are costly, visible near-infrared spectroscopy (VIS-NIR-SWIR) from 400 to 2500 nm is often used to estimate SOC, leveraging a statistical model which relates SOC analytical data to the spectral information obtained in the laboratory from a collection of sieved, air-dry samples. This study evaluates VIS-NIR-SWIR to predict SOC content of southwestern German soils after resampling the recorded soil spectral library (SSL) to match Sentinel-2 bands. It also examines whether these prediction models can then be applied to Sentinel-2 satellite imagery for rapid mapping of topsoil SOC content at a state-wide scale.A suite of 1500 VIS-NIR-MIR soil spectra, recorded from air-dried, 2-mm, sieved soil samples, were associated with SOC analytical data obtained from different soil surveys done by the State Authority for Geology, Resources and Mining (LGRB) in Baden-Wuerttemberg, Germany. Partial least squares (PLS) regression and support vector machines on PLS latent variables (PLS-SVM) were used for spectroscopic modelling. Final estimates showed good results with regards to PLS-SVM with a ratio of performance to deviation (RPD) of 1.96, while slightly less accurate predictions were found for calibration models based on resampled spectra with a RPD of 1.64. The successful spectral prediction model for SOC from resampled spectra was subsequently used to produce a high-resolution map of topsoil SOC content on croplands for entire Baden-Wuerttemberg, Germany. To identify bare dry soil pixels a worfklow was established that creates per-pixel composites utilizing three years of Sentinel-2 satellite imagery and spectral indices. Direct standardization (DS) was used for the correction of environmental factors such as variable moisture conditions using a set of representative locations with both dry spectra and Sentinel-2 band values.Preliminary results indicate that a calibration model based on resampled spectra from a region-specific SSL can be applied to multi-temporal Sentinel-2 data for rapidly estimating the spatial distribution of topsoil SOC content. Unlike official SOC products currently available for Baden-Wuerttemberg, Germany, the given approach can easily be updated if additional data becomes available or new sensors emerge, for instance, from hyperspectral satellite missions such as EnMAP or CHIME.
Development of a long-term SO2 column data record from satellite nadir UV sensors
Authors: Theys Nicolas , Li Can , De Smedt Isabelle , Lerot Christophe , Yu Huan , Vlietinck Jonas , Hedelt Pascal , Krotkov Nickolay , Van Roozendael Michel
Published: February 2023

As part of its Climate Change Initiative extension program (CCI+), the European Space Agency started a new activity aiming to develop space-based long-term climate data records for precursors gases involved in the formation of aerosols and ozone (https://climate.esa.int/en/projects/precursors-for-aerosols-and-ozone/about/). The targeted trace gases are NO2, SO2, HCHO, CHOCHO, CO and NH3.For SO2 in particular the project relies on recent developments for Sentinel-5 Precursor/TROPOMI based the Covariance-Based Retrieval Algorithm (COBRA). This algorithm will be used to build consistent column retrievals from a series of four satellite sensors (GOME, SCIAMACHY, OMI and TROPOMI), covering nearly three decades of observations.Here, we give an overview of the SO2 development activities in the Precursors CCI+ project. To achieve the project objectives, an extensive comparison of results is performed in the form of a round Robin exercise. This includes comparison of different algorithms, but also testing of various processing options for ancillary data such as cloud and surface reflectance parameters. First results from the round Robin exercise are presented with a focus on OMI, in particular the comparison between COBRA and Principal Component Analysis (PCA) column retrievals. Preliminary results using COBRA for the historical sensors GOME and SCIAMACHY are also shown. 
New Antarctic spin-up method results in committed Thwaites glacier collapse
Authors: van den Akker Tim , Lipscomb William H. , Leguy Gunter R. , van de Berg Willem Jan , van de Wal Roderik
Published: February 2023

Projections of sea level rise are subject to large uncertainties in the contribution of the Antarctic Ice Sheet (AIS), as it is unclear how AIS dynamics will evolve over time. Ice sheet models use spin-up techniques to initialize the ice sheet to the present-day state. Previous attempts using the Community Ice Sheet Model (CISM) assumed that the ice sheet is in equilibrium at the end of the spin-up. This assumption limits the contribution of model drift, but does not match observations and might bias future projections. For this reason, we have incorporated present-day thickness change rates from Smith et al. (2020) in our Antarctic spin-ups. As in previous spin-ups, we tune basal friction coefficients beneath grounded ice, and ocean temperatures beneath floating ice, to match observed present-day thickness. In the new procedure, CISM is also forced to match thickening and thinning rates, with the surface mass balance (SMB) adjusted to allow the AIS to maintain the observed thickness and grounding-line locations. This technique improves the modelled velocities in regions with substantial thinning. When the SMB adjustments are removed, the modelled ice sheet exhibits the observed thickness change rates. We use this initialised state to project AIS evolution without additional forcing (‘committed climate change’). For a range of parameter settings, this causes Thwaites glacier to collapse irreversibly, without further ocean warming. The time of initiation of collapse is sensitive to model parameters, but once initiated the collapse is largely complete within two to three centuries. The sensitivity tests are carried out for a range of parameters related to basal sliding and various ocean warming scenarios.
The Global Geodetic Observing System (GGOS) - infrastructure underpinning Science and Society -
Authors: Miyahara Basara , Sánchez Laura , Sehnal Martin , Craddock Allison
Published: February 2023

The Global Geodetic Observing System (GGOS) is a collaborative contribution of the global Geodesy community to the observation and monitoring of the Earth System. Geodesy is the science of determining the shape of the Earth, its gravity field, and its rotation as functions of time. Essential to reach this goal are stable and consistent geodetic reference frames, which provide the fundamental layer for the determination of time-dependent coordinates of points or objects, and for describing the motion of the Earth in space. With modern instrumentation and analytical techniques, Geodesy is capable of detecting time variations ranging from large and secular scales to very small and transient deformations – all with increasing spatial and temporal resolution, high accuracy, and decreasing latency. The geodetic observational and analysis infrastructures as well as the high-quality geodetic products provide the foundation upon which advances in Earth and planetary system sciences and applications are built. In this way, GGOS endeavors to facilitate and enable production and sharing of the Earth observations needed to monitor, map, and understand changes in the Earth’s shape, rotation, and mass distribution. GGOS also advocates the global geodetic frame of reference as the fundamental backbone for measuring and consistently interpreting global change processes as well as the essential geospatial infrastructure to ensure a homogeneous and sustainable development worldwide.GGOS closely works with its parent organization, the International Association of Geodesy (IAG), to keep these fundamental geodetic contributions sustainable. The IAG Services provide the infrastructure and products on which all contributions of GGOS are based, and the IAG Commissions and IAG Inter-Commission Committees provide expertise and support to address key scientific issues within GGOS. Additionally, GGOS supports the IAG by strengthening external and interdisciplinary relations and contributions to the broader geospatial information community, including relevant United Nations groups, in particular, the UN Committee of Experts on Global Geospatial Information Management (GGIM), its Subcommittee on Geodesy, and the new UN Global Geodetic Centre of Excellence (scheduled to commence operations in 2023). The main contribution of GGOS in this regard is to support actions and initiatives to communicate the value of Geodesy to society as well as to help to understand and solve complex issues facing the global geodesy community. Towards this objective, GGOS have developed a comprehensive Geodesy portal (https://ggos.org/) including detailed descriptions of geodetic observations (https://ggos.org/obs/) and products (https://ggos.org/products/), and various outreach tools such as short videos to explain the roles and importance of Geodesy to non-geodesists.
Recent methane trends derived from S5P/TROPOMI data
Authors: Hachmeister Jonas , Schneising Oliver , Buchwitz Michael , Burrows John P. , Notholt Justus , Buschmann Matthias
Published: February 2023

Methane (CH4) has a relatively long tropospheric lifetime and is consequently a well-mixed greenhouse gas. CH4, released by severaltypes of human activity and natural processes, is one important driver of climate change. The global mean concentration of CH4 hasincreased by 156% between the beginning of the industrial revolution around 1750 and 2019, reaching roughly 1866 ppb in 2019 (IPCC).The time dependence of this increase is not well understood. For example, it is not entirely clear why CH4 growth rates reached record high values in 2020 and 2021. Furthermore, the number of published growth rates (annual methane increases) is limited and includes datafrom NOAA and the Copernicus Climate Change Service. Hence the rate of increase of CH4 calculated from independent data sources arevaluable for cross-verification and in furthering our understanding of the methane cycle.The TROPOMI instrument onboard the Sentinel-5P satellite provides daily CH4 data with a spatial resolution of roughly 7x7 km²and global coverage. We analyze the TROPOMI CH4 data with the goal of determining robust values of the annual methane increases (AMI)for both global and zonally resolved data. For this we utilize a dynamic linear model approach to separate the underlying methane level,the seasonal and short-term variations. The AMIs are defined as the difference in the underlying (i.e. fitted) methane level betweenthe first and last day of a year. In this contribution, we present first results for global and zonal TROPOMI AMIs for the years 2019-2022.We compare the resulting global TROPOMI AMIs with data from NOAA and Copernicus and discuss the distribution of zonal AMIs for the given years.
Analyzing the Land Subsidence activity in the Joshimath Region of Indian Himalayas Using Persistent Scatterer Interferometric Synthetic Aperture Radar (PSInSAR)
Authors: Awasthi Shubham , Jain Kamal
Published: February 2023

 The Himalayan region is prone to natural disasters, including land deformation caused by tectonic activity, earthquakes, landslides, and human activities such as construction of large infrastructural projects. In the Joshimath region, located at the base of Middle Himalayas, there has been a significant number of reported cases of visible deformation in roads and buildings over the past six months i.e. between July 2022 to December 2022, with 610 buildings, including houses and hotels etc., showing cracks in their walls and foundations. This poses a danger to both the community and infrastructure in the area. To study this deformation, time-series synthetic aperture radar interferometry was used to monitor land subsidence in the region. An analysis of land subsidence in the entire Joshimath region was conducted using Time-Series Synthetic Aperture Radar Interferometry, and the land deformation velocity for was calculated using a PsInSAR approach, which measured the displacement velocity in mm/year. The results indicated that the rate of displacement, measured in Line of Sight (LOS) deformation velocity, was in the range of +187.55 mm/year to -84.65 mm/year. A positive sign indicates movement away from the SAR sensor, while a negative sign represents movement towards the sensor. The highest rate of subsidence was observed in the northwest region of the Joshimath that is in the range +103.22 mm/year to +187.55 mm/year, while areas in the north and central region also experienced high to moderate subsidence of +63.73 mm/year to +103.22 mm/year. In contrast, the southwest region was found to have experienced expansion measuring −84.65 mm/year to -13.13 mm/year. Additionally, the southeast region of the town had a rapid land subsidence ranging from -13.13 mm/year to -5 mm/year towards the lower part of the town. The potential causes of deformation in the Joshimath region are believed to include an inadequate drainage system in the town, high levels of erosion caused by the Alaknanada river, which is impacting the stability of the slope on which the town is situated, and recent development of large infrastructure projects in this disaster-prone area, that include construction of a hydropower project tunnel by NTPC and the expansion of the Chardham Highway. The fact that the ridge on which the town sits is composed of debris from past landslides further exacerbates these issues, as the terrain formed by such debris has a lower bearing capacity, making it a poor foundation for heavy infrastructure development.
The reason for the wide particle spread during the 17 April 2021 SEP event
Authors: Dresing Nina , Rodríguez-García Laura , Jebaraj Immanuel , Warmuth Alexander , Wallace Samantha , Balmaceda Laura , Podladchikova Tatiana , Strauss Du Toit , Kouloumvakos Athanasios , Palmroos Christian , Krupar Vratislav , Gieseler Jan , Xu Zigong , Mitchell Grant , Cohen Christina , de Nolfo Georgia , Palmerio Erika , Carcaboso Fernando , Kilpua Emilia , Sanchez-Cano Beatriz
Published: February 2023

The widespread SEP event of 17 April 2021 was observed by five longitudinally well-separated observers in the inner heliosphere covering distances to the Sun from 0.42 to 1 au: BepiColombo, Parker Solar Probe, Solar Orbiter, STEREO A, and close-to-Earth spacecraft. The event, which produced relativistic electrons and protons, was associated with a complex and long-lasting solar eruption involving a long-duration flare, a medium-fast Coronal Mass Ejection (CME), an EUV wave and a complex solar radio burst activity lasting for 40 minutes including type II bursts, marking the presence of a shock, as well as four distinct groups of type III bursts. Our comprehensive analysis of the multi-spacecraft in-situ and remote-sensing observations suggests different source regions for the electron and proton SEP event with a stronger shock contribution for the proton event and a more likely flare-related source of the electron event. We furthermore determine that the four distinct injection episodes, marked by the radio type III burst groups, cover a longitudinal range of about 110° and were a main ingredient for the wide SEP spread. We consider this a new scenario that must be taken into account as a potential contributor to widespread SEP events.
Freshwater input and water mass interactions in the Uummannaq fjord system
Authors: Ponsoni Leandro , Ollevier Anouk , Develter Roeland , Boone Wieter
Published: February 2023

The climate is rapidly changing in the Arctic, where global warming is reported to be about up to four times the global average in the last two decades. Aligned with this Arctic Amplification, other climate-related phenomena are also changing, or are bound to change, on a regional scale. For instance, the accelerated glaciers’ melting is forcing a transition of some glaciers from marine- to land-terminating systems and, therefore, impacting the balance of freshwater input into the oceans. As consequence, other ocean climate-related processes (e.g., water masses (trans)formation, baroclinicity of geostrophic currents) are expected to be impacted.Within this context, and as part of the “Innovative study on regional high-resolution imaging of glacier induced plankton dynamics in West-Greenland fjords (IOPD)” project, we visited the fjord system in the Uummannaq area, off Western Greenland, aboard the R/V Sanna, from 28/Jun to 10/Jul/2022. In this region, fjords are marked by both land- and marine-terminating glaciers. During the cruise, we performed 47 hydrographic stations of the entire water column into 5 different fjords - from their mouth to the innermost accessible location. These stations are complemented by an offshore transect from the fjord mouth to the shelf edge.Based on the in-situ measurements described above, complemented by other historical oceanographic measurements and state-of-the-art datasets for solid and liquid freshwater input provided by the Geological Survey of Denmark and Greenland (GEUS), we aim at characterizing the fjord system in the Uummannaq area in perspective of the ongoing climate changes. More specifically, this work addresses the following questions (i) What is the long-term and recent freshwater input to the region? And, is this input undergoing changes in the latest years? (ii) How are the water masses quantitatively distributed within the fjords and adjacent continental shelf? Are there differences between fjords? And, how do the connections with the adjacent continental shelf take place? (iii) Are there differences between marine- and land-terminating systems in terms of (solid and liquid) freshwater input and water mass distribution in the region? If so, what are these differences?
The GOME-type Tropical Tropospheric Ozone Essential Climate Variable (GTTO-ECV) satellite data record and an updated S5P-BASCOE dataset
Authors: Heue Klaus-Peter , Loyola Diego , Coldewey-Egbers Melanie , Dameris Martin , Lerot Christophe , van Roozendael Michel , Hubert Daan , Errera Quentin , Chabrillat Simon
Published: February 2023

A tropospheric ozone time series from 1995 until end 2022 has been generated within ESA’s Climate Change Initiative+ programme. The GOME-type Tropical Tropospheric Ozone Essential Climate Variable (GTTO-ECV) satellite data record combines data from GOME, SCIAMACHY, OMI and the three GOME-2 missions. The retrieval is based on the Convective Cloud Differential technique, which limits the coverage to the tropical belt (20°S to 20°N). We generated two monthly mean data sets at 1° x 1° resolution: one corresponds to a tropospheric column up to 200 hPa as in the previous CCI data release (Heue et al., 2016), while the other is limited to 270 hPa and includes the operational Sentinel-5P data as an additional sensor. An internal reprocessing of S5P CCD using 200 hPa is planned but might not be ready in time. Besides a consistent reprocessing of the CCD data for individual sensors, we also updated the harmonising scheme. The mean bias as well as the mean annual cycle relative to the reference instrument (OMI) are used to correct for the differences between the sensors.Heue et al (2016) claimed a mean tropospheric ozone trend of +0.7 DU/decade (1995-2015). How did the trend change with the extended data set? The GTTO-ECV data record will be used to investigate the tropical mean trend as well as temporal and local changes in the trends. Also, a comparison with modelled tropospheric ozone data and the respective trends might be given.As a second data product we provide the global S5P-BASCOE tropospheric ozone data. The complete time series of the S5P total ozone columns has been reprocessed recently. The reprocessing includes an update of the Level1 data as well as reprocessed cloud and O3 total columns. We use the reprocessed OFFL ozone data set in combination with BASCOE assimilation constrained stratospheric ozone profiles to calculate the tropospheric ozone columns. Relative to ground-based observations the total OFFL columns show a small positive bias. Before the retrieval of the tropospheric ozone column this bias is subtracted. The updated tropospheric ozone columns might also be compared to modelled tropospheric ozone columns.
Inputs of reactive nitrogen from wet deposition and fertilization in a tropical montane catchment characterised by smallholder farming.
Authors: Kasebele Miriam , Jacobs Suzanne , Breuer Lutz
Published: February 2023

Reactive nitrogen from anthropogenic inputs such as fertilizers and its changes in the transport and fate in the environment as a consequence of changes in land management may alter the nitrogen balance of a catchment and thus its concentrations in water bodies. This can be enhanced by increased wet and dry deposition of nitrogen from anthropogenic activities. In the Mau Forest Complex in Kenya, the annual export of nitrogen from a catchment dominated by smallholder agriculture was reported to be almost double those from the native forest. Fertilization and livestock management are assumed to have contributed to this shift, but no empirical evidence is available to support this. Furthermore, the contribution of the nitrogen wet deposition through rainfall and throughfall to the nitrogen balance has not been quantified yet. This study aims at determining the contribution of nitrogen wet deposition and anthropogenic inputs to the nitrogen balance of a 27 km² headwater catchment characterized by smallholder farming in the Mau Forest Complex. Rainfall and throughfall samples were collected from precipitation collectors in 10 different locations within 24 hours after 11 rainfall events in the span of 9 weeks. Anthropogenic inputs were estimated from a household survey (n=185). Median and Interquartile range (IQR) concentrations of total dissolved nitrogen (TDN) were slightly higher in rainfall i.e. 0.7 (0.4–0.9) mg N L−1 than in throughfall i.e. 0.6 (0.4–0.8) mg N L−1, resulting in median wet deposition of 0.04 (0.02–0.06) kg N ha−1 from rainfall and 0.03 (0.01–0.06) kg N ha−1 from throughfall per sampled rainfall event (4.7 mm; 2.5–8.1 mm). Extrapolated to the full year, this leads to an estimated nitrogen input from wet deposition of 11.7 (9.5-12.5) kg N ha−1 yr−1 from rainfall and 6.4 (5.7-9.6) kg N ha−1 yr−1 from throughfall, although this estimate does not consider seasonal changes in TDN concentrations in rain- and throughfall. Median inputs of nitrogen from inorganic fertilizer was 25 (15.2–40.2) kg N ha−1 yr−1, whereas annual inputs from livestock were 76 (49-125) kg N ha-1 yr−1.Reactive nitrogen inputs from farming and livestock are higher than the estimated wet deposition and could therefore significantly impact the catchment nitrogen balance. It follows therefore that a continual and increase use of nitrogen inputs from manures and fertilization with inorganic fertilizers, as well as further forest cover loss for agricultural expansion may lead to future elevated levels of nitrogen in the environment, leading to risks of progressive enrichment of water bodies and further nitrogen imbalances. To keep these in check, appropriate manure management strategies, fertilizer application and control of forest conversion cannot be overemphasized.
Shear-slip and Complex Fracturing by CO2 Injection in Naturally Fractured Granite at Geothermal Conditions
Authors: Pramudyo Eko , Goto Ryota , Sakaguchi Kiyotoshi , Watanabe Noriaki
Published: February 2023

Previous studies showed that cloud-fracture networks (CFNs), networks of permeable microfractures densely distributed over rock body, formed in granite at superhot geothermal conditions (> ~400 °C) through the stimulation of pre-existing microfractures by low-viscosity water near and above its critical temperature. The CFNs were also shown to form in granite at conventional (~150 – 300 °C) and superhot geothermal conditions by injection of low-viscosity CO2, through the same mechanism as that by low-viscosity water at superhot geothermal conditions. The stimulation of pre-existing microfractures by the low-viscosity CO2 implied that CFNs may be formed in the matrix (i.e., unfractured rock) of naturally-fractured conventional and superhot geothermal environments, where conventional bi-winged hydraulic fractures are known to be difficult to be achieved by injection of cold water. The present study illustrates the possibility of CFN formations in naturally-fractured geothermal environments, along with the shear-slip of the natural fractures, through CO2-injection experiments into cylindrical granite samples, each contained a sawcut (representing a natural fracture) inclined from the sample axis, under geothermal conditions. The experiments show that CO2 injection induced a larger cumulative shear displacement on the sawcut at conventional geothermal condition than at superhot geothermal condition. CFNs were formed at conventional and superhot geothermal conditions; nonetheless, the fracture-apertures were thinner for the CFN formed at conventional geothermal condition. The results imply that CFNs may be formed in naturally fractured geothermal environments, and may provide additional fluid-flow paths between the stimulated natural fractures.
Interpolation of design rainfall at ungauged locations exploiting the potential of convection-permitting climate models.
Authors: Formetta Giuseppe , Marra Francesco , Dallan Eleonora , Borga Marco
Published: February 2023

Quantifying design rainfall events at varying durations is crucial for assessing flood risk and mitigating losses and damages. Yet, in a changing climate, they are fundamental tool for a reliable design of water related infrastructures, such as flood retention reservoirs, spillways, and urban drainage systems. Usually, design rainfall is quantified where rain gauges are located, and regionalization methods are used to provide estimates in ungauged locations. During the last years, convection-permitting climate models (CPM) are receiving increasing attention because, thanks to their high spatial resolution (~3km) and ability of explicitly resolving atmospheric convection, they allow for better estimating precipitation spatial patterns and extreme rainfall at multiple durations compared to coarser models.In this work, we combine at-site rain gauge measurements with CPM simulations, within a non-asymptotic statistical framework for the analysis of extreme rainfall. We aim at quantifying the added value of the physics-based information provided by CPM simulations for the estimation of high quantiles of rainfall in ungauged locations.     The performance of the new regionalization approach is compared with traditional interpolation methods (i.e. interpolation of distribution function parameters) using leave- one-out cross-validation as well as considering different rain gauge densities.Preliminary results show that the proposed methodology based on CPM simulation provides: i) similar performances compared to traditional gauge-based regionalization methods for high station density scenarios and ii) improved performances for low station density scenarios.
Observing climate zones boundaries change: Kazakhstan's case study
Authors: Yessimkhanova Kalamkas , Gede Mátyás
Published: February 2023

Presently, climate change is an urging topic and mapping the effects of climate change is a crucial part. According to the evaluation by United Nations Development Programme, more than half of the territory of Kazakhstan exposed ecological crisis as drought, extreme weather events, fires and others. In this regard, this study is important for conducting research on both observation and visualization of the boundaries change of climatic zones on the land area of Kazakhstan. The Köppen climate classification was applied as a reference. In particular, such variables as temperature and precipitation were used for climatic zones classification. Extensive database of Google Earth Engine spatial analysis platform allows to leverage climate reanalysis datasets for many decades. Although, World Metereological Organization recommends considering 30-year period to witness the climate change, there is limited data access for the region of interest. Thus, only 21-year time frame was analyzed, specifically, time range between 2000 and 2021. Results are presented as time-series maps of classified climate zones and may benefit other researchers on their projects related to climate change.
The relevance of coupled climate model WRF-CTSM for land-atmosphere interactions analysis
Authors: Mužić Iris , Hodnebrog Øivind , Berntsen Terje Koren , Yilmaz Yeliz , Sillmann Jana , Lawrence David , Swenson Sean , Sobhani Negin
Published: February 2023

A credible assessment of spatial and temporal variability of the water and energy budget is of viable importance for the quantification of the observed changes and prediction of extremes in a changing climate. However, an accurate representation of feedback mechanisms between the land surface and the atmosphere is a key source of uncertainty in climate models.WRF-CTSM (Weather Research and Forecasting model, WRF, and Community Terrestrial Systems Model, CTSM) is a state-of-the-art modelling tool that represents the forefront in the climate modelling community and unifies the recent model development activities across weather, climate, water and ecosystem research. This study is the first to provide a systematic regional scale assessment of the WRF-CTSM coupled climate model performance in the European context - in the high-latitude region encompassing Norway, Sweden and Finland.A 10-year-long regional WRF-CTSM simulation (2010-2020) using meteorological boundary conditions from the ERA5 reanalysis is performed on a 10.5 km horizontal resolution to evaluate the representation of hydroclimatic variables through comparison against ERA5 and a range of observational datasets. Changes in boundary layer variables such as soil and near-surface air temperature, soil moisture and snowpack are essential for the assessment of the land-atmosphere feedbacks in this region and are thus selected as central for the analysis of the model skill. Besides the WRF-CTSM simulations using default CTSM settings, this study investigates the added value of including the recently developed Hillslope Hydrology model in WRF-CTSM runs that has the potential to improve the understanding of the role of topography and hydrology on the soil moisture and snowpack variability.Preliminary results indicate the capacity of WRF-CTSM to identify the high-temperature susceptible areas in Norway, Sweden and Finland and reproduce the interannual variability and spatial patterns of hydroclimatic variables in the respective region.
Sensitivity of the cancellation factor spectral variations for temperature investigation in the mesospheric nightglow layer
Authors: Bellisario Christophe , Simoneau Pierre , Jaffré Ewen , Keckhut Philippe , Hauchecorne Alain
Published: February 2023

The infrared emission lines observed between 80 and 100 km known as nightglow allow the investigation of dynamic phenomena such as gravity waves acting on local temperature and density. Swenson and Gardner (1998) introduced the cancellation factor as the link between the nightglow intensity observed and the local temperature. In a previous study, we investigated local changes in spectral intensity using the main source of the nightglow OH. The variations showed dependencies on vibrational levels due to the differences in their reaction coefficients. We now extend the sensitivity study by performing 3D spatial tests. We briefly describe the nightglow evolution model (NEMO), which is developed on a pressure level grid where the gravity wave perturbation is applied. Inherent parameters of the perturbation such as spatial wavelengths are confronted to their impacts on the nightglow layer. In addition, spectral integration over infrared InGaAs camera is applied to allow comparisons with measurement campaigns.
NASA Particle and Single-Scattering Database (PaSS-DB) in Support of Particulate Matter Retrievals
Authors: Kuo Kwo-Sen , Fenni Ines , Schrom Robert , Adams Ian , Ton Dai Hai , Huffman George , Braun Scott
Published: February 2023

A significant portion of the atmospheric particulate matters are irregular without symmetry, e.g., dust particles, ice crystals, snowflakes, etc. Some of them are of heterogeneous composition, e.g., melting hydrometeors and droplets with inclusions. Solving the electromagnetic scattering problem for these particles are computationally intensive. It becomes impractical and very inefficient to repeatedly solve the same problem. Moreover, due to the lack of symmetry, every orientation of the particle has a unique solution, generating considerably greater volumes of data than the solutions for particles with nice symmetry. Storing the solutions and making them accessible is far more sensible, economical, and thus sustainable. The Particle and Single-Scattering Database, PaSS-DB, initiative aims to catalog, warehouse, and disseminate these atmospheric particles and their electromagnetic scattering solutions using an enterprise-grade database management system and a web interface. We report the early progress of the effort in this presentation.
Assessing floodplain dynamics using radar interferometry in the East Ganga Plains, India
Authors: Singh Manudeo , Bookhagen Bodo
Published: February 2023

Floodplains are essential elements of terrestrial water storage and perform various hydrogeomorphic, ecological, and socio-economic services. Ganga Plains are one of the world's largest and most populous plains. The East Ganga Plain (EGP), other than being densely populated, is also a fluvially highly dynamic region. This region hosts ‘hyperavulsive’ rivers and numerous wetlands, some of which are the largest wetlands of the Ganga Plains. Due to frequent flood hazards, all rivers of the region are embanked on both banks. We are investigating the surface dynamics of the region by calculating the surface displacement using InSAR (Interferometric Synthetic Aperture Radar) time series in ISCE-2 and Mintpy environments. We calculated the InSAR stack for the period Oct 2016 to May 2022 and built the connected network for the next three neighbours. We iteratively chose the multilooking value of azimuth 11 and range 78 to mitigate the low coherence issues due to the vegetation. We used ascending and descending tracks of Sentinel-1 to calculate the horizontal and vertical components of the velocity. Our results show that the entire area is tectonically subsiding. However, the spatial pattern of subsidence rate is varying – surfaces with seasonal water cover, such as active channel belts and wetlands, are exhibiting the highest subsidence rates with up to 7 cm/y and twice the subsidence rates of non-water surfaces. In many regions, the subsidence is accelerating.We are using satellite-based multispectral indices (MNDWI, NDVI) and in-situ measurements such as groundwater depth and rainfall and land use data to investigate the disparity in the subsidence rates in the region. The preliminary results suggest that the waterbodies are drying, vegetation cover and irrigation are increasing, and rivers are disconnected from their floodplains due to embankments. We emphasise the anthropogenic role in the acceleration of the subsidence due to river embankment, augmented by a high drawdown of groundwater for irrigation purposes.
Disasters And Development Nexus: A Review of Vulnerability Assessment on The East Coast of India
Authors: Aditya Bharadwaz Ganni Satya Venkata Sai
Published: February 2023

Planned and unplanned developments are increasing hugely in coastal areas all over the world. Changing climate and associated coastal hazards are also increasing. In this study, a systematic literature review has been adopted to understand the Disasters and Development Nexus on the east coast of India. Vulnerability scenarios have been assessed from the existing literature. Indian coast also experiencing massive constructional developments in the last few decades. The intensity and recurrence of coastal hazards are increasing at an enormous rate. Which is causing massive economic as well as life and livelihood losses. Particularly Cyclonic storms and associated coastal flooding has become yearly events on the east coast of India. As a community's exposure to potential hazards depends on its socioeconomic condition, the poor coastal communities on the eastern coast are defenseless and exposed to potential hazards. Considering the importance of planning measures, some long-term mitigation measures, such as embankment restructuring and realignment, restoration of mangrove forests, and salinity reduction by adopting scientific land use planning, may reduce the impact of hazards. Similarly, some short-term management strategies like an early warning system, 24 h digital monitoring system, and the construction of adequate flood and cyclone shelters can improve the effectiveness of the disaster response system.
Impacts of meteorological biases on forecasting surface PM2.5 concentration over the Beijing-Tianjing-Hebei region
Authors: Du Qiuyan , Zhao Chun , Feng Jiawang , Yang Zining , Xu Jiamin , Gu Jun , Zhang Mingshuai , Xu Mingyue , Lin Shengfu
Published: February 2023

Forecast biases in the meteorological fields have long been recognized as the main limitation on accuracy and predictability of air quality forecast. However, the quantitative studies on the impacts of meteorological forecast biases on air quality forecast are insufficient, and its mechanisms in different seasons are still unclear. In this study, series of forecasts from 2-Day (24 ~ 48-hour) to 7-Day (144 ~168-hour) for January, April, July, and October of 2018 are conducted over the Beijing-Tianjing-Hebei (BTH) region and the impacts of meteorological forecast bias on surface PM2.5 concentration forecast at each leading-time are analyzed. The results show that the forecast biases of surface PM2.5 concentration caused by meteorological forecast biases keep increasing with the increasing leading-time in all seasons. The impacts of meteorological forecast biases are strongest in spring, with the forecast bias of PM2.5 concentrations up to 187% in the 7-Day forecast, followed by autumn (123%), summer (112%) and winter (80%). By the contribution analysis of relevant processes and their changes with the increase of leading-time, it is found that the dry deposition, transport and PBL mixing are the main processes contributing to the growth of forecast bias of surface PM2.5 concentrations. In addition, the correspondence between the contributions of relevant processes and the meteorological factor are examined. It is found that the changes of contributions of processes are closely related to the difference in the forecasted meteorological factors such as surface winds, wind fields at 850hPa, PBL height, shortwave radiation and precipitations at each leading-time. This study highlights the importance of meteorological forecast bias in surface PM2.5 concentration forecasting, and provides useful information for the improvement of air quality forecast accuracy and supports the policies of air pollution controlling.
Stable isotopes as a tool for improving rainfall-runoff modelling in South Africa
Authors: van Rooyen Jared , Watson Andrew , Vystavna Yuliya , Miller Jodie
Published: February 2023

Understanding the way in which a water budget is distributed within a hydrological system is imperative in the prediction of the systems behaviour when this water budget has changed. A complex interaction of variable flow rates, residence times and reactive transport, controls the available streamflow of a river system not only over seasonal changes, but under longer term climate fluctuations as well. Hydrological modelling techniques have been instrumental in predicting these changes by monitoring/simulating rainfall, river and groundwater contributions but are dependent on robust data collection through the maintenance of old infrastructure and the creation of new infrastructure. South Africa is a pertinent example of the decline of gauging infrastructure and a prime use case for novel stable isotope techniques as an accessory to traditional hydrological modelling in semi-gauged watersheds. Furthermore, to constrain contributions in modified systems, that include reservoirs and land use changes, isotopes present an opportunity to assess unpredictable water mobilisation in the streamflow system. In this study, stable isotope measurements of rainwater, groundwater and stream water (δ2H and δ18O), together with a tertiary mixing model were used to develop an isotope-enabled version of the JAMS/J2000 rainfall-runoff model, named J2000iso. The application was applied to the upper Berg River catchment, a catchment impacted by recent drought, but important for regional water supply. Compared to the base version, the J2000iso had 13% more simulated interflow, with 56% less variance in the ensemble results and less overall process uncertainty. The J2000iso was also more robust than the base version during a subsequent validation. The isotope-enabled models provided a means to constrain the proportion of surface runoff, interflow and baseflow considering the streamflow signal changes due to upstream reservoir operations. As many catchments in South Africa are still ungauged or impacted by upstream reservoirs, the J2000iso model provides a means to simulate hydrological processes, given the appropriate collection of isotope and auxiliary data.
Energetic electrons in the solar corona for the long duration event of 9 May 2021 as diagnosed from X-ray and radio observations.
Authors: Vilmer Nicole , Musset Sophie , Zhang Minghui , Klein Karl-Ludwig , Paipa David
Published: February 2023

In this paper we will present preliminary results of an X-ray flare that occurred on 9th May 2021 for which the thermal and non-thermal X-ray signatures were detected both from the Earth direction by Fermi/GBM  and by STIX on Solar Orbiter at 97° from the Sun-Earth line.  This flare was also well observed in radio with the ground-based instruments  in Nançay and in the interplanetary space by WIND/WAVES and RPW on Solar Orbiter . The X-ray event shows both an impulsive phase observed above 25 keV by STIX and FERMI and followed by a more gradual phase observed up to 15 keV by both STIX and FERMI. In the decimetric/metric radio domain, this event shows a group of type III bursts extending to the interplanetary medium as well as type IV emission.  We shall discuss here the relative temporal evolutions of HXR emissions at different energies with those of the radio fluxes at different frequencies, as well as the spatial evolution of the X-ray and radio sources during the different phases of the event. We shall also investigate the evolution of the characteristics of the non-thermal electrons detected in the corona associated to both implusive and gradual phase of the flare.
Deployment of dense nodal network during unrest: investigation of the Vulcano-Lipari System (Italy) with Local Earthquake Tomography
Authors: Barat Célia , Savard Geneviève , Muñoz Francisco , Stumpp Douglas , Alparone Salvatore , Ricci Tullio , Ursino Andrea , Palano Mimmo , Reyes Hardy Maria-Paz , Pruiti Lucia , Planes Thomas , Sparacino Federica , Bonadonna Costanza , Ruch Joël , Caricchi Luca , Lupi Matteo
Published: February 2023

The Vulcano-Lipari System is a volcanic complex located in the central sector of the Aeolian Archipelago in southern Italy. The edifice is affected by complex tectonics and develops upon the trans-extension of the Aeolian-Tindari-Letojanni Fault System. This fault is proposed to control magmatism and acts as a preferential pathway for upwelling of magmatic and supercritical fluids. Over the last three decades, Vulcano Island underwent several volcanic crises and since September 2021 it has been showing signs of increasing activity and volcanic unrest. Temperature, degassing, seismic activity, and deformation rapidly increased causing temporal evacuation of the inhabitants of the most affected regions. During the unrest in October 2021, we deployed 196 3C geophones all around Vulcano and south of Lipari to record the seismic signals for a full month, as part of the VulcaNODES project. The resulting seismic catalog confidently contains more than 7000 volcano-seismic and volcano-tectonic events with an average local magnitude of -0.32. This catalog is used to produce an unprecedented travel-time time-lapse tomography of the unrest. Seismic tomography is a powerful tool for observing structures at depth beneath volcanic systems, using seismic waves generated by earthquakes. Such a dense network combined with the exceptional seismic signal recorded will provide tomographic time series of the plumbing system every 1-3 days for a month. The still ongoing VulcaNODES project aims at observing fluids evolution along the volcano’s tectonic structures on a daily basis, providing new insights on processes usually difficult to record on short timeframes, and shedding light on the plumbing system on a high resolution.
The role of the subsurface in the energy transition – (some of) the (scientific) challenges
Authors: Miocic Johannes
Published: February 2023

The transition towards carbon-free, renewable based energy systems is a central element to limit global warming and is one of the key societal challenges we are currently facing. The subsurface offers many different pieces for the energy transition jigsaw, from renewable energy from geothermal sources to large volumes of pore-space to permanently sequester carbon dioxide. The subsurface also provides several options for storing renewable energy over seasonal timescales, by storing renewable energy surplus converted into hydrogen and compressed air. As the subsurface can be utilized for many different energy related purposes, it becomes clear that it has to be a crucial part of the energy-transition.  However, most subsurface utilization technologies are not yet used on the scale that is needed for a successful energy transition. One reason for this lies in the incomplete understanding of (geological) processes that occur in the subsurface during, and after, the operation of these technologies. Predicting the performance and the potential of subsurface utilisation in the energy transition can also be hampered by limited data availability and the uncertainties associated with sparse datasets. Here, some of the key geoscience challenges that need to be solved for a timely energy transition are presented and some potential solutions are reviewed. The subsurface can, and must, play an important role in tomorrow’s green energy systems!
The relative importance of the amount and spatial distribution of vegetation as indicators of dryland function
Authors: G. Mayor Angeles , Bautista Susana , Maestre Fernando , Rodríguez Francisco
Published: February 2023

Bare-soil connectivity and vegetation cover have proven to be good indicators of dryland function. The two properties are closely correlated and reflect the combined role of both the amount and spatial distribution of vegetation, making it difficult to disentangle the relative importance of each. Using partial correlation analyses between bare-soil connectivity, vegetation cover and soil function data from 109 dryland plots distributed worldwide, we have investigated the independent explanatory role of the two vegetation metrics along a variety of environmental gradients. Our results show that bare-soil connectivity and vegetation cover swap their relative importance as indicators of dryland function along most of the environmental gradients considered, with bare-soil connectivity increasing its independent explanatory role for both the milder and harder end of the gradients, and pattern-independent vegetation cover being a better predictor for medium-moderate  conditions.