bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving global SO2 emission inventories using Sentinel-5P TROPOMI satellite data
Authors: Jost Adrian , Beirle Steffen , Borger Christian , Theys Nicolas , Ziegler Steffen , Wagner Thomas
Published: March 2024

We provide a global database of SO2 emissions from point sources generated from TROPOMI observations of SO2 (COBRA product) for the time range from May 2018 to July 2022. Our algorithm derives the advection of SO2 by combining TROPOMI SO2 column densities and ERA5 wind fields, i.e., taking the product of the vertical column density gradient and the horizontally projected wind speed. In addition, several corrections, e.g., for satellite sensitivity and topography, are applied. For each point source, error estimates are given, considering the uncertainties of the various retrieval steps.A fully automated iterative detection algorithm of point sources from around the world forms the basis of our catalog. The catalog includes a list of 130 locations identified as substantial anthropogenic SO2 point sources. Most of these locations are close to power plants included in the Global Power Plant Database (GPPD) or match entries in previously compiled SO2 inventories.The emissions in our catalog are in good agreement (Pearson correlation coefficient (r) of 0.82) with those recorded in existing SO2 datasets (Fioletov et al., 2023) but are higher by about 36%.By comparing our SO2 catalog with matches in the global NOx catalog compiled by Beirle et al. (2023), information on the used fuel and applied filtering measures is provided. We observe an SO2 to NOx mass ratio ranging from 0.8 to 141.5 with a mean of about 10 for the selected point sources.The SO2 catalog was created as part of the World Emission (2022) project, funded by ESA, which focuses on quantifying emissions of different species that can be detected by satellite instruments. The complete SO2 catalog will be made publicly available through the World Emission Portal at https://app.world-emission.com.
Earthquake Early Warning Systems based on Fiber Optic Distributed Acoustic Sensing in the Sea of Marmara
Authors: Coşkun Zeynep , Özgür Havva Gizem , Koç Berkay , Dal Meryem Ece , Özkan Erkan , Erkorkmaz Tayfun , Pamukçu Niyazi Bedri , Şahin Ramazan Can , Tunç Süleyman , Kalafat Doğan , Pınar Ali , Buldanlı Kadri , Özener Haluk
Published: March 2024

The Istanbul Natural Gas Distribution Company (İGDAŞ) has recently embarked on utilizing existing Fiber-Optic (F/O) cables to enhance disaster prevention and mitigation efforts in Istanbul. We are exploring the potential of a novel technology called F/O Distributed Acoustic Sensing (DAS) for earthquake early warning systems. The strategic placement of the F/O cable, which crosses the North Anatolian Fault in the Marmara Sea, presents a unique opportunity for monitoring seismic activity. While seismic stations exist around the Marmara Sea, the absence of online operating Ocean Bottom Seismometer (OBS) stations makes the F/O cable the only sensor positioned across the fault lines expected to rupture during a major earthquake.The monitored F/O cable, originally intended for telecommunications, spans 60 kilometers in the Sea of Marmara. Over the past 7 months starting in June 2023, more than 160 earthquakes ranging from magnitudes 1.0 to 7.5 have been recorded through the F/O cable. Notably, the F/O DAS system successfully captured significant distant events, notably the February 6, 2023, M7.8 and M7.5 earthquakes in Kahramanmaraş. This initiative highlights the critical stages, obstacles, and best practices associated with deploying this technology. It underscores the importance of precise cable layout, optimal sensor density, range optimization, and the conduction of shaking table tests.Shaking table experiments were conducted to compare noise levels across various sampling rates. By subjecting a Force-Balanced Accelerometer (FBA) and F/O cable to simulated seismic activity resembling the 1999 Sakarya Earthquake (M6.9) with sine signals at frequencies of 0.25 Hz, 0.5 Hz, 1.5 Hz, 2 Hz, and 3 Hz, observations revealed that reducing the sample rate to 200 sps significantly lowered the interrogator's instrumental noise compared to 2000 sps. Hence, a lower sample rate proved advantageous in achieving a better Signal-to-Noise Ratio (SNR).Through the analysis of acoustic signal variations along the F/O cable, the DAS systems can accurately pinpoint and characterize earthquake events, facilitating timely warnings. F/O DAS technology boasts distinct advantages in earthquake detection due to its capacity to capture a broad spectrum of seismic signals, ranging from low-frequency tectonic shifts to high-frequency ground vibrations. The effectiveness of F/O DAS measurements relies on proper coupling, ensuring the efficient transfer of acoustic signals to the optical fiber, thereby ensuring precise detection and interpretation of seismic activity.
SilvaCuore, a tool for monitoring the health status of Italian forests
Authors: Castellaneta Maria , Borghetti Marco , Colangelo Michele , Colle Giacomo , Rita Angelo , Ripullone Francesco
Published: March 2024

The health status of forests is becoming increasingly endangered by drought-induced climate change. In recent decades, widespread forest decline has been reported  worldwide in all biomes. The reports of forest mortality across Italy and the need to be better aware of the extent and magnitude of the phenomenon were the assumptions that led to the development of a web-application called SilvaCuore. A team of researchers from the University of Basilicata has carried out this project to safeguard Italian forests. The aim is to combine scientific research and active community participation (Citizen Science project) through the use of new technologies, in order to better monitor and manage Italy’s forest heritage. The SilvaCuore web-application seeks to census the declining forest sites located in Italy and to create a database that can be used as a basis to improve the forest management. SilvaCuore has been developed as a Progressive Web Application and can be accessed from smartphones, tablets and PCs due to its responsive user interface. The user, after registering in to the web-application, is guided by a user-friendly step-by-step procedure in the reporting process that, besides a brief description or more complex data, allows to take some photos and the GNSS position of the site. The report outcomes will be automatically collected in a cloud web database, immediately accessible to the research team. Verified reports will become publicly accessible from the same web-application, ready to provide a concrete insight into the health of our forests. The application is also linked to a website that provides additional information about the project, the rationale behind the app, and the research activities carried out by the SilvaCuore team. It is crucial to improve the citizen's approach to nature and environmental issues: a more aware citizen will be a citizen who cares more about the environment and its preservation. An case in point is the agreement with PEFC Italy (Program for the Endorsement of Forest Certification Schemes): first, PEFC-certified forest owners will be able to utilize the web-application, in order to implement adaptive forest management and second, this will provide useful alert reporting. The challenge here is to be able to create a monitoring network that not only monitors the current state of forest health but also evaluates potential future dynamics, and becomes increasingly capable of responding to the threat of forest decline.
Testing the gravitational redshift by time transfer with Moonlight constellation
Authors: De Marchi Fabrizio , Tartaglia Pasquale , Sesta Andrea , Iess Luciano
Published: March 2024

The recent boost toward lunar exploration and the ensuing increase in the number of missions to the Moon makes the development of a Lunar Radio Navigation System (LRNS) highly desirable. To this aim, ESA conceived the Moonlight project: a constellation of small satellites in highly eccentric orbits around the Moon, composed of four satellites in Elliptic Lunar Frozen Orbits (ELFOs) with a good coverage of the southern hemisphere.
Eccentricities are about 0.63, periselenium altitudes about 1800 km, while the orbital periods are 24 hours. Thanks to radio tracking at X or K band from Earth stations, the Moonlight constellation will provide a communication and navigation service for users on the lunar surface and cis-lunar space [1]. These orbits and radio configuration may be favorable for improved tests of the foundations of general relativity.
The Local Lorentz and Local Position invariances (LLI, LPI), together with the Universality of Free Fall (UFF), constitute the Einstein Equivalence Principle (EEP). The validity of the EEP is one of the cornerstones of the General Relativity (GR). LLI and LPI are usually tested by comparing the GR predictions with the measured gravitational redshift of clocks onboard Earth satellites or interplanetary spacecraft (Galileo mission, [2]).
To date, the LPI has been verified up to a 10-5 level by the analysis of Doppler data provided by GSAT0201 and GSAT0202 satellites of the GALILEO constellation [3].
Our aim is to investigate, by means of detailed simulations, if the one-way Doppler link between the clocks onboard the Moonlight satellites and the Earth stations can be used to improve the current knowledge about the Local Lorentz and Local Position invariances.
We simulate the experiment by assuming different scenarios, such as 1) type of onboard clocks (e.g. miniRAFS or DSAC-2), 2) orbital geometry and 3) mission duration.
 

[1] L. Iess et al. (2023) Proceedings of the 36th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS+ 2023), Denver, Colorado, September 2023, pp. 4029-4050. https://doi.org/10.33012/2023.19428
[2] Krisher, T. (1993) “The Galileo Solar Redshift Experiment”. PRL 70, 15. https://doi.org/10.1103/PhysRevLett.70.2213.
[3] Delva, P. et al. (2018) “Gravitational Redshift Test Using Eccentric Galileo Satellites”, Phys. Rev. Lett., 121, 231. https://doi.org/10.1103/PhysRevLett.121.231101
 
Groundwater quality in two coastal fens and the influence of storm surge flooding and rewetting with seawater
Authors: Racasa Erwin Don , Liu Haojie , Toro Miriam , Janssen Manon
Published: March 2024

Coastal peatlands are unique ecosystems situated at the interface of land and sea. Past human activities, specifically drainage, have turned these carbon sink coastal regions into carbon sources. To mitigate climate change, recent management strategies focus on rewetting drained coastal peatlands. In this study, we aimed at characterizing surface and groundwaters in two coastal fens and examine the impacts of seawater input events caused by a storm surge (freshwater-rewetted) and rewetting with seawater (seawater-rewetted). Prior to the events, our findings reveal variable marine influence on surface and groundwater in the past which depends on distance from the coast, peat thickness, and possibly, drainage networks. After the storm surge, increases in specific conductivity (SC), chloride, and sulfate concentrations in surface waters persisted for up to a year. Increases in surface water dissolved inorganic carbon (DIC) and dissolved organic carbon (DOC) concentrations were also observed. In peat groundwater, a sustained increase in DOC concentrations that reached 526 mg DOC L-1 was observed at a shallower depth (max: -0.59 masl) while a delayed increase was observed at a deeper depth (max: -1.41 masl). High dissolved carbon concentrations were still observed in peat groundwater until the end of the observation period, three years after the storm surge. For the seawater-rewetted fen, significant changes in surface water properties were observed, which included SC, chloride, pH, DOC, DIC. The initial DOC concentrations in peat groundwater decreased, but later, showed the same high concentrations similar to the storm surge flooded fen. No apparent impacts to deeper sandy aquifers from both sites were observed. Overall, storm surge flooding impact on surface water properties lasted for a limited time while rewetting with seawater significantly and drastically changed the surface waters as the peatland was transformed into a lagoon-like environment. Peat groundwater properties in both sites did not change significantly, however, depth-dependent variable increases in DOC concentrations could be expected. The increases in DOC concentrations in peat groundwater were accompanied by increased SC and decreased pH conditions. Lastly, the ongoing salinization of seawater-rewetted fens may lead to brackish-rewetted environments with higher concentrations of seawater salts and potentially create new biogeochemical reactive mixing zones of ground- and seawater.
Characterization of biogeochemical self-purification processes in the Vjosa River network focusing on different spatial and temporal scales
Authors: Hoxha Sonja , Griebler Christian , Karwautz Clemens , Singer Gabriel , Beqiraj Sajmir
Published: March 2024

The Vjosa River and its tributaries represent a large and dynamic river network characterized by a near natural flow regime and largely undisturbed hydromorphological dynamics. Due to the high connectivity (e.g. the lack of dams and regulation in the main river stem), the Vjosa River is a hotspot of natural biodiversity and may serve as an ecological reference system.The self-purification potential of an ecosystem describes the resistance and resilience to contamination (disturbances). In rivers, the contaminants are attenuated and degraded not only in the visible river channels, but most importantly in the hyporheic zone and the riparian corridor. The subsurface is a vital bioreactor, that hosts an immense river- and groundwater-borne biodiversity.Here we target the key biogeochemical processes involved in the cycling of carbon and nutrients in a qualitative and quantitative manner. The spatio-temporal distribution and transformation of different carbon (e.g. DOC, DIC, CO2, CH4), nitrogen (e.g. NO3-, NO2-, NH4+), and phosphorus (e.g. PO43-, Ptot) species are studied in detail at different spatial scales. Extrapolation from flow-through sediment microcosms to natural river sections of various dimensions (mesoscale to macroscale) will allow a good estimation of material import, transformation, attenuation, and export. The role of the microbial community, in the water and attached to the sediments, will be analyzed via high throughout sequencing to determine its composition and functions.The outcome of this study will help to better understand the functioning river ecosystems from the micro to the catchment scale as a basis for in-depth evaluation of future sustainable management options. The Vjosa River has been proclaimed a national park recently, and options for ecotourism are currently developed by its management authorities. In the light of global change, the Vjosa River network shall serve as a reference system for other rivers in Europe and a unique field laboratory for assessing biogeochemical processes in an intact environment.
Developing a mobile app for adopting efficient irrigation technologies for cotton production in India
Authors: Ponce Pacheco Mario Alberto , Adla Soham , Guntha Ramesh , Aravindakshan Aiswarya , Presannakumar Maya , Tyagi Ashray , Nagi Anukool , Pastore Prashant , Pande Saket
Published: March 2024

Smallholder farmers are critical to global food production and natural resource management. Due to increased competition for water resources and variability in rainfall due to climate change, chronic irrigation water scarcity is rising particularly in drought-prone regions like Vidarbha, Maharashtra (India). Improving irrigation water efficiency is critical to sustainable agricultural intensification; however, adopting a new technology represents a certain level of risk for the farmers, who invest time and economic resources in changing their practices. Because of the uncertainties in the rainfall (monsoon onset and dry spells), in addition to the upcoming global change, the expected yield is unsure and variable; so, a paradigm comparison between different irrigation technologies is not clear.  We have developed software that allows farmers to make decisions in real time based on the implemented practices (fertilisation and irrigation) in their crops, mainly cotton. By implementing a socio-hydrological dynamic model, the software provides a risk forecast of the yield and profit the user can expect at the end of the season under the current practices; in addition, the software computes the forecast of the production under a provided best practices scenario, so the users can compare and improve their practices. The model also considers state variables the water storage water and biomass production, providing an understanding of the impact of the executed practices in the natural resources. Finally, we implemented a kernel principal component analysis (KPCA) to consider the impact of socioeconomic factors on the yearly outcome, based on previous surveys performed in the area. We’ve focused on object-oriented programming (OOP) approach in order to optimise the management of the information. The app not only processes social and agricultural information provided by the user but also retrieves and continually updates climate datasets from the web, as well as market prices. The farmers can request the execution of the social-hydrological model to our servers from their own mobile devices, helping to the adoption of technologies. By following an agile methodology, the mobile app has been tested with farmers in order to get feedback from real users; this brought the opportunity to redesign the functionality based on the correct understanding of information and, a fast and clear management of the tool. In addition, this software represents a useful tool to capture and follow information about the use of water by farmers.
SeaHeat: Assessing Baltic Sea potential and risks for thermal energy source
Authors: Siiriä Simo-Matti , Nummelin Aleksi , Laakso Lauri
Published: March 2024

The Baltic Sea presents a unique environment for thermal energy usage through heat pumps, which has yet to be extensively explored. Its distinct characteristics, such as a strong vertical stratification dominated by salinity and relatively shallow depth, create a setting where, despite cold winters, the water beneath the halocline remains relatively warm. Identifying areas where temperatures remain sufficiently warm is the first step in utilising this resource for energy production. During winter, with water temperatures typically under 5 °C, the water flows required for meaningful power plants would be comparable to the magnitudes of small rivers, necessitating a thorough assessment of the environmental impacts of both extracting warm water and the outflow of cooler water.We will present the first results of a project in which we have used the existing Baltic Sea reanalysis from Copernicus Marine Services to  (i) identify locations within the Baltic Sea where water temperatures reliably stay above specific trigger temperatures, thereby offering feasible sites for energy extraction and (ii) assess  the environmental impacts of intake and outflow volumes based scale analysis of the local ocean heat budget.We will also present a decision support tool designed for end-users considering the implementation of sea-heat power plants. This tool provides a preliminary assessment of both the opportunities and risks associated with specific sites, offering a crucial first step in the decision-making process for potential sea-heat energy projects.
Nodal Local Earthquake Tomography of La Soufrière Volcano, Guadeloupe
Authors: Jiwani-Brown Elliot Amir , Savard Geneviève , Barsuglia Filippo , Rosselli Alberto , Fischanger Federico , Truffert Catherine , Lupi Matteo
Published: March 2024

La Soufrière is an active andesitic stratovolcano lava dome at 1467 m elevation. It is the most recently eruptive centre of the Guadeloupe archipelago in the eastern Caribbean Sea. Previous activity has consisted of effusive, explosive magmatic, and phreatic eruptions. Many hazards are associated with La Soufrière volcano, including explosive blasts, pyroclastic flows, acid degassing and contamination of groundwater sources. Since 1992, increased seismic and fumarolic activity at La Soufrière has raised the alert level to yellow, peaking with a volcanically triggered ML 3.7 earthquake in 2018.  In the framework of the MEGaMu project, innovative geophysical subsurface imaging methods are deployed at La Soufrière to produce a high-resolution model of the volcanic edifice at up to ~1 km depth to improve our understanding of the volcano’s shallow structure. In October 2023, we deployed an array of 48 3-component 5 Hz nodal geophones around the base of the volcanic massif and the summit crater, recording continuous passive seismic data at a sampling of 250 Hz for one month. An electrical resistivity campaign was conducted at the same time, providing an outstanding opportunity to compare the derived 3D seismic velocity model with a 3D electrical resistivity model on a similar scale. In this study, we apply seismic ambient noise tomography using data from our temporary nodal network and nearby existing broadband stations to produce Rayleigh wave group velocity maps and a 3D model of shear wave velocity. This model is interpreted with the 3D resistivity model to determine the extent of the shallow hydrothermal system and known fault zones crossing the volcanic massif. Such a multi-scale and multi-physics geophysical prospection approach greatly helps in reducing subsurface uncertainty in the interpretation of geophysical datasets.We use new nodal technologies and up-to-date applications of seismic passive noise tomography to analyse Rayleigh wave shear-velocity dispersion data from a nodal seismic network of 48 3-component units, and generated 2D group velocity maps at different periods, and 3D depth insertion of shear wave velocities. We compare this to a 3D electrical resistivity, carried out simultaneously with seismic deployment, to better constrain the subsurface plumbing system based on comprehensive geophysical methodologies.
Matched Field Processing of train vibrations for opportunistic surface wave tomography
Authors: Rebert Théo , Bardainne Thomas , Cai Caifang , Allemand Thibaut , Chauris Hervé
Published: March 2024

Railways are exposed to geotechnical hazards such as sinkholes or subsidence because they encounter many geological settings. Railway subsurface imaging is thus important in order to detect small anomalies in the elastic properties of the upper 50 meters of soils. Seismic interferometry applied on train induced signals is a promising technique, and previous works have shown clear Rayleigh waves and reflections in the retrieved Green’s functions. However, extracting the dispersion curves of the reconstructed Rayleigh waves in a automated and robust way with high-resolution is challenging.We study a continuously acquired dataset consisting of a dense array of five lines of accelerometers deployed parallel to 120 m of track. We use Matched Field Processing (MFP) to recover a high-resolution S-wave velocity model of the subsurface. The workflow begins by correlating signals in time windows when the train is outside the array, to ensure nearly planar wavefronts before the interferometry step. However, using only trains far from the array discards the measurements associated to the train crossing the array which have a very high signal-to-noise ratio but are difficult to model. We observe experimentally that train crossings the array generate correlations compatible with the isotropic and uncorrelated source distribution hypothesis used in passive seismology. Under this assumption, we correlate signals when the train is directly next to the sensors. Combined with correlations for the train in the far-field, this allows to track the Rayleigh dispersion curve in the very high frequencies (> 50 Hz). This broadband dispersion curve extraction, along with the balanced azimuthal coverage of our image due to the source diversity, is helpful for reliable imaging of shallow structures ranging from the bottom of the ballast to the bedrock. Since array methods are robust, and trains are repeatable sources, this paves the way for reliable monitoring of the subsurface with unprecedented temporal and spatial resolution.
The influence of microtopography on soil carbon accumulation and nutrient release from a rewetted coastal peatland
Authors: Wang Miaorun , Liu Haojie , Rezanezhad Fereidoun , Zak Dominik , Lennartz Bernd
Published: March 2024

Coastal peatlands have been frequently blocked from the sea and artificially drained for agriculture. With an increasing awareness of ecosystem functions, several of these coastal peatlands have been rewetted through dike removal, allowing seawater flooding. In this study, we investigated a recently rewetted peatland on the Baltic Sea coast to characterize the prevailing soils/sediments with respect to organic matter accumulation and the potential release of nutrients upon seawater flooding. Eighty disturbed soil samples were collected from two depths at different elevations (–0.90 to 0.97 m compared to sea level) and analyzed for soil organic matter (SOM) content and carbon:nitrogen (C:N) ratio. Additionally, nine undisturbed soil cores were collected from three distinct elevation groups and used in leaching experiments with alternating freshwater and Baltic Sea water. The results demonstrated a moderate to strong spatial dependence of surface elevation, SOM content, and C:N ratio. SOM content and C:N ratio were strongly negatively correlated with elevation, indicating that organic matter mineralization was restricted in low-lying areas. The results also showed that the soils at low elevations release more dissolved organic carbon (DOC) and ammonium (NH4+) than soils at high elevations. For soils at low elevations, higher DOC concentrations were observed when flushing with freshwater, whereas higher NH4+ concentrations were found when flushing with brackish water. Recorded NH4+ concentrations in organic-rich peat reached 14.82 ± 9.25 mg L–1, exceeding Baltic seawater (e.g., 0.03 mg L–1) by two orders of magnitude. A potential sea level rise may increase the export of NH4+ from low-lying and rewetted peat soils to the sea, impacting adjacent marine ecosystems. Overall, in coastal peatlands, geochemical processes (e.g., C and N cycling and release) are closely linked to microtopography and related patterns of organic matter content of the soil and sediments.(The original article has been published in Geoderma, Volume 438, 116637; DOI: 10.1016/j.geoderma.2023.116637)
A Later Onset of the Rainy Season in California
Authors: Lukovic Jelena , Chiang John , Blagojevic Dragan , Sekulic Aleksandar
Published: March 2024

Californian hydroclimate is strongly seasonal and prone to severe water shortages. Recent changes in climate trends have induced shifts in seasonality, thus exacerbating droughts, wildfires, and adverse water shortage effects on the environment and economy. Previous studies have examined the timing of the seasonal cycle shifts mainly as temperature driven earlier onset of the spring season. In this paper, we address quantitative changes in the onset, amounts, and termination of the precipitation season over the past 6 decades, as well as the large-scale atmospheric circulation underpinning the seasonal cycle changes. We discover that the onset of the rainy season has been progressively delayed since the 1960s, and as a result the precipitation season has become shorter and sharper in California. The progressively later onset of the rainy season is shown to be related to the summer circulation pattern extending into autumn across the North Pacific, in particular, a delay in the strengthening of the Aleutian Low and later southward displacement of the North Pacific westerlies.
Air Quality Modeling for Policy Support in Poland – system overview and recent results
Authors: Durka Pawel , Kaminski Jacek W. , Struzewska Joanna , Jeleniewicz Grzegorz , Norowski Aleksander , Gienibor Aneta , Kawka Marcin , Baginski Wojciech , Lobocki Lech
Published: March 2024

The role of air quality modelling as a supporting tool for providing information to citizens and policymakers is becoming more significant, as shown in recent research studies and the enhancement of modelling applications in a proposal for the new Ambient Air Quality Directive.Starting in 2018, the Institute of Environmental Protection – National Research Institute (IEP-NRI) is legislated to provide modelling in support of air quality policy for Poland. This support covers modelling and its analysis required for annual air quality assessment (46 zones, including 30 urban areas), the impact of transboundary transport analysis on pollution concentrations in Poland, representativeness of monitoring stations, 5-year assessment for the purpose of zone classifications, modelled scenarios for National Air Quality Improvement Plan. An operational air quality forecast for 72 hours is also modelled every day and is being used for public information, as well as eventual air quality alerts. All simulations are calculated with the GEM-AQ model (Kaminski et al., 2008), configuration and resolution are fit for purpose and depend on application - concerning the European Commission Joint Research Centre (JRC) Forum for Air Quality Modeling (FAIRMODE) guidelines and evaluation methods. Most of the analyses cover the modelling of at least primary pollutants (NO2, SO2, O3, PM10, PM2.5) and are based on a high-resolution Central Emission Database made by The National Centre for Emissions Management (KOBiZE) for Poland. Results and analysis are provided to the State Inspectorate of Environmental Protection, Ministry of Environment and Climate and published on IEP-NRI web pages.We will present the configuration and solutions of the modelling system built in IEP-NRI, as well as the most recent results. The strengths of the described approach work in progress, and further development plans will be shown and discussed.
Potential limitations of ammonia flux data beyond 72h after field application of slurries 
Authors: Neftel Albrecht , Häni Christoph , Kupper Thomas , Valach Alex , Hafner Sasha
Published: March 2024

Ammonia volatilization from animal slurry applied to fields is a major source of air pollution in Europe. The ALFAM2 model  was developed for estimating ammonia emission from such sources and is used in research, as well as  for inventory calculations. Until now, the focus has been on emissions up to 72 hours after application (ALFAM2 model version 1.2), as it was generally assumed that over 90% of total emissions from the applied nitrogen occur during this period. The recently updated ALFAM2 model (version 2.3) now includes emission data up to 168 h after application, which has led the model to indicate substantial emissions between 72 and 168 h leading to a significant increase (
Greenhouse gas emissions from valley-bottom wetlands in an agricultural tropical highland system, Taita Hills, East Africa
Authors: Gubamwoyo Sharon , Gettel Gretchen Maria , Kisha Damaris Guranya , Leitner Sonja , Weigelhofer Gabriele , Hein Thomas
Published: March 2024

Globally, agriculture is one of the main drivers of wetland loss, leading to reduced soil carbon (C) and changes in greenhouse gas (GHG) emissions. In recent decades, wetland loss in Africa appears to be faster than the global losses, at about 43% compared to 35% globally. Valley-bottom wetlands in African highland regions support the livelihoods of >65% of the people who live there, but the effect of agricultural conversion on soil C and GHG emissions is understudied. This study compares GHG emissions between 1 intact, 12 agricultural (converted), and 10 recovered valley-bottom wetlands in Taita Hills, Kenya. Using the static gas chamber method, CO2, CH4, and N2O emissions were measured monthly from April 2023 to date along with soil NO3-N, NH4-N, soil C, and soil moisture. The results indicate that CO2 emissions from the converted wetlands is similar to recovered wetlands (mean = 183 ± 11 SE mg CO2-C m-2 h-1 and mean = 174 ± 13 SE mg CO2-C m-2 h-1 respectively; p > 0.05). This is in contrast with both CH4 and N2O emissions, which showed strong differences (p
Projections of the Fire Weather Danger over Central Europe using EURO-CORDEX simulations
Authors: Bayar A. Serkan , Ramos Alexandre M. , Gouveia Célia , Pinto Joaquim G.
Published: March 2024

Increasing temperatures and harsher drought conditions in recent decades have enhanced the risk of wildfire in many regions across the globe. Recent fire activity in Central Europe raised concerns about the possible expansion of the fire weather danger conditions under climate change outside the present-day fire-prone regions, such as the Mediterranean Basin. Here, we employ the widely used Canadian Fire Weather Index (FWI) system to assess the historical and future trends in the fire weather danger for Central Europe. Calculation of the originally proposed FWI requires utilizing noon-time temperature, relative humidity, wind, and accumulated precipitation. Using the ERA5 reanalysis dataset, we make sensitivity analyses with different combinations of alternative input data for noon-time meteorological parameters and estimate their biases.This study uses an ensemble of regional climate models (RCM) from the EURO-CORDEX domain. We first compare the results from ERA5 with the RCM ensemble for the historical period. Then, we analyze future projections for Central Europe under different global warming levels (+2 K and +3 K). Results indicate that the fire-prone areas consistently increase under warmer climate conditions, including emerging fire-prone regions in Central and Northern Europe.
Use of Dynamic Mode Decomposition for the reconstruction of contaminant release history 
Authors: Ciriello Valentina , Libero Giulia , Tartakovsky Daniel M.
Published: March 2024

The design of effective remediation actions is crucial to protect human health and the environment against the risks posed by aquifer contamination. To improve the predictions of plume properties and the assessment of the efficiency of remediation strategies, much effort has been spent to model subsurface transport processes. One of the most challenging components of the analysis is the identification of the sources of groundwater contamination, which involves the estimation of both locations of the contaminant release and its temporal history. This inverse-modeling task must deal with the complexity of flow path in the aquifer, while contending with the sparsity (both in space and time) of observations of solute concentration. Subsurface heterogeneity and data scarcity require the use of computationally expensive probabilistic methods to solve this inverse problem. We present dynamic mode decomposition (DMD) as an alternative tool to reduce the computational burden of contaminant source identification. DMD is a data-driven, equation-free technique able to interpret the behavior of a system and generate a computationally efficient reduced-order model of the system behavior directly from the data. The method is based on singular value decomposition and consists of a regression of spatially distributed data, collected from a dynamical system at multiple times, onto locally linear dynamics. It allows one to discern dominant spatiotemporal patterns in the dynamical system behavior. We use DMD algorithms to recombine these structures to get system states back in time and reconstruct the contaminant release history.
Changes in the response of the carbon cycle to astronomical forcing during the Silurian Ireviken biogeochemical event
Authors: Arts Michiel , Cramer Brad , Calner Mikael , Rasmussen Christian M. Ø , Da silva Anne-Christine
Published: March 2024

The Silurian Ireviken Event is a biogeochemical event characterised by extinctions among several marine groups and a major perturbation to the global carbon cycle. In the Altajme core from Gotland, Sweden, the associated Ireviken Carbon Isotope Excursion (ICIE) reaches peak values of ~6‰. Within the ICIE, the main peak of -6‰ (δ13Ccarb) is superimposed by multiple short-term and small amplitude positive peaks (+1.00 ‰ δ13Ccarb), while the tail of the main peak is superimposed by multiple small amplitude negative peaks (-1.55 ‰ δ13Ccarb). To understand the processes behind these recurrent small amplitude peaks, the high-resolution XRF scanning data of the Altajme core were used to identify astronomical cycles to put astrochronological constraints on the δ13Ccarb curve. Based on the XRF data and its resulting astrochronology, the small amplitude positive and negative δ13Ccarb peaks occur during insolation minima in intervals enriched in carbonate relative to the surrounding lithology. The XRF proxy data indicates that during times when elevated carbonate content coincides with elevated δ13Ccarb values, insolation minima induced an arid environmental state in the basin. This led to decreasing runoff and a strong anti-estuarine circulation, which in turn lowered pelagic productivity and increased photozoan carbonate production, resulting in the deposition of carbonates with elevated δ13Ccarb values. This contrasts to the concomitant insolation maximum, which induced a semi-arid state in the basin, resulting in some runoff, a (sluggish) anti-estuarine circulation in the basin, some pelagic productivity and carbonates being primarily produced by heterozoans, resulting in the deposition of marly carbonates with low δ13Ccarb values. The XRF proxy data indicates that during times when carbonate-rich intervals coincide with more negative δ13Ccarb values, insolation minima induce a semi-arid state in the basin, resulting in some runoff, a (sluggish) estuarine circulation in the basin, some pelagic productivity and carbonates being primarily produced by heterozoans resulting in the deposition of marly carbonates with low δ13Ccarb values. This contrasts with the concomitant insolation maximum which induced humid conditions in the basin, resulting in increased runoff, a (strong) estuarine circulation and high primary productivity, leading to the deposition of marly shales with higher δ13Ccarb values. The shifting baseline climatic conditions during the Ireviken Event are inferred to have changed the response of the depositional environments to astronomical forcing, in changing (carbonate) productivity and circulation, which in terms modulated the carbon cycle, resulting in an imprint of astronomical cycles in the ICIE.
Working with Paul Tapponnier on the Structure, Age and Evolution of the Red Sea
Authors: Dyment Jerome , Afifi Aboud , Briais Anne
Published: March 2024

As part of his sabbatical at Schlumberger in the ARAMCO in 2008-2009, Paul Tapponnier started a complete reassessment of the plate tectonic structure, age and evolution of the Red Sea.  Public and industrial geophysical data, including gravity, magnetics, and seismics, covering the whole Red Sea, have been (re)interpreted in view of recent concepts.  This study concluded that oceanic lithosphere covers a large part of the Red Sea, although the expression of seafloor spreading in the whole ultraslow-spreading northern Red Sea and on the earlier stage of opening in the central and southern Red Sea is hidden by the thick salt cover.  We have been associated to this research between 2009 and 2013 and beyond, and will present some highlights of this exciting period.
Uncertainty Analysis in streamflow Estimation Using Chemical Gauging Technique with Multiple Instruments in High Mountain Environments.
Authors: Muñoz Sepúlveda Aldo , Muñoz Daniela , Quezada Salvador , Montserrat Santiago , Niño Yarko
Published: March 2024

Measuring streamflow in high mountain environments, crucial for understanding contributions from snow and glaciers, poses logistical challenges due to the complexities of accessing study areas and the temporal and spatial variability in flow rates throughout the day, particularly during spring and summer. Consequently, the volumetric balances, essential for estimating diffuse contributions, can be disrupted by the temporal variability inherent in transient environments.
In this context, this work details the fieldwork development of a synoptic streamflow measurement protocol tailored for transient high mountain environments using the chemical gauging technique. The protocol minimizes injected salt amount by measuring it at different positions with different instruments at different times of the day, ensuring correlated flow rate measurements on each instrument. Instruments include Aqua Troll 600 Multiparameter Sonde, HOBO U24-001 Conductivity Data Logger, and Sommer Tracer system.
The study area focuses on the Yerba Loca stream basin in the central Andes of Chile, a protected area with an average elevation of around 3400 meters above sea level and an average slope of 28.4°. This basin is characterized by naturally occurring Acid Rock Drainage (ARD). The studied stream exhibits characteristics of high mountain runoff, with water depths not exceeding one meter, bed roughness in the order of tens of centimeters, and slopes that can reach 40%. The study area has a roughness height comparable to the flow depth, with values around unity indicating macrorough flow.
The protocol's development involved conducting measurements in a test area situated approximately 2000 meters above sea level. Measurements were taken around the confluence of the stream with a lateral tributary during four field campaigns in different seasons of the year. Furthermore, the field protocol was applied in a high mountain glacierized area at around 3500 meters during the thaw season, evaluating its performance in a period of high variability within a day.
As a result of these activities, more than 500 streamflow measurements were obtained and analyzed to estimate flow rates and their associated uncertainties. The uncertainties for each measurement were evaluated based on the instrument used, its distance from the injection point, and various conditions present in the stream. Additionally, recommendations are provided for conducting synoptic gauging with multiple instruments of varying precision.
The authors gratefully acknowledge the financial support of the National Agency for Research and Development of Chile (ANID): ANID Project AFB230001.  Aldo Muñoz would like to thank ANID for the doctoral grant: ANID-Subdirección de Capital Humano/Doctorado Nacional/2021-21212042 and CODELCO for the funding received from Piensa Minería-Doctoral Thesis Competition.
Real-time Data Using Services: A Co-design Opportunity in ICOS Cities Project 
Authors: Marttila Tatu , Gaziulusoy Idil , Berns Katie , Ikonen Liisa
Published: March 2024

ICOS Cities is an EU-funded project that aims to develop a systematic greenhouse gas measurement system for urban areas. The Work Package (WP) 1 of the project investigates economic, societal, and political dimensions that influence how city decision-makers use and will use emission data. The two main aims of WP1 are to: 1) Collect, unlock and harmonise prior information on city climate infrastructures and emissions, and 2) Investigate relevant services the city observatory should provide to answer the needs of cities in terms of estimation of their GHG emissions and implementation of their climate policies. Stakeholder engagement is facilitated in WP1 to map the information, service and policy needs of the city administrations, as well as by conducting social surveys and semi-structured interviews with the citizens. The authors are responsible for WP1 Task 1.4, which aims to co-design a number of service prototypes demonstrating the potential of the project in the pilot cities context and develop a general methodology for service development for the use of other cities. In the initial phase of our research, we conducted a benchmarking study to develop an in-depth understanding of existing services used by the cities to display and make sense of emission data and feed into policy processes from the perspective of their intended users. To achieve this, first, a number of stakeholders in different European cities have been surveyed to collect data on the existing services. Then, the technological constraints and the situation in three selected pilot cities of the project (Zurich, Munich, Paris) have been further explored in selected in-depth interviews with pilot city representatives or other topical experts. As a result, we developed an initial typology of existing services targeting different users of GHG emissions data, including but not limited to city-level policymakers. Several service types related to GHG monitoring were found, focusing on interactive carbon impact data, emission reduction monitoring, and services for estimating emissions of different types. These services have also been targeted at different actor groups and geographical resolutions and have different design realisations. Our findings indicate that services that connect real-time measurements (or even periodic measurements) to activities in municipal planning currently do not exist. Despite the availability of real-time data, the practices and standards on how such data is processed and used are only emerging, and the data is scattered amongst several actors. There also exist major challenges to moving assessments further from scope 1 (the direct impacts of energy and fuel use), and the process depends on many types of supplementary data. These gaps, amongst other elements of the service system, indicate significant opportunities for new service development, which we will focus on in the next phase of the project.
Leveraging recent advances in Large Language Models for the ocean science community
Authors: Lguensat Redouane
Published: March 2024

Large Language Models (LLMs) have made significant strides in language understanding, including natural language processing, summarization, and translation, and they have the potential to be applied to a range of climate-related challenges. For instance, LLMs can be leveraged for data cleaning and transformation, and also assisting scientists/engineers in their daily work tasks.For the machine learning community, the year 2023 was arguably the year of breakthroughts in LLM use in production. I present in this work the exciting potential for recent advances in LLMs to revolutionize how the ocean science community can interact with computer code, information gathering, dataset finding, etc. Specifically, I will present simple applications of how these advancements in Natural Language Processing (NLP) can assist the NEMO ocean model community. Examples range from using question answering systems for browsing efficiently NEMO documentation to creating conversational agents or chatbots that can assist not only new members wanting to learn about the NEMO model but also confirmed users. An important aspect of this work is relying only on open source LLMs, evaluating the performances of several models and discussing the ethical implications of these tools. I also discuss the question of whether using these LLMs blindly without domain knowledge is a good idea, as an important chunk of this work can arguably be easily done by anyone with good computer science skills thanks to the democratization of data science tools and learning materials. 