bluuebunny/crossref_metadata_2025 huggingface dataset:
Multi-site analysis of the impact of surface ozone on European forests
Authors: Vieira Inês , Meunier Félicien , Sitch Stephen , Brown Flossie , Gerosa Giacomo , Janssens Ivan , Boeckx Pascal , Bauters Marijn , Verbeeck Hans
Published: February 2023

Tropospheric Ozone (O3) is a secondary pollutant with a positive radiative forcing and many negative effects on air quality, human health and ecosystems at different scales. In fact, O3 acts as a strong oxidant in plants, negatively impacting many cellular and molecular processes, such as modifying rubisco activity, reducing stomatal conductance and inducing early leaf senescence. Furthermore, when the O3 levels at the surface are high (typically above 40 ppb), these combined effects may decrease the photosynthetic carbon gains, mainly detectable at the leaf level but also important at the tree and stand scales. In this study, we intend to evaluate the effects of O3 on Gross Primary Production (GPP) at four European forest sites (Belgium, France and Italy) using local measurements, both for O3, eddy-covariance (GPP) and meteorological variables (including air temperature (TA), relative humidity (RH), vapour pressure deficit (VPD), short-wave radiation (SW), wind and precipitation). We first applied a series of statistical analyses to identify the impact of O3 and meteorological variables on GPP for each site. In a second step, we used a process-based model that simulates GPP using the Farquhar equations parameterised for each site to quantify O3-induced GPP reductions. Our results showed that the dominant meteo factor is site dependent. The SW appears to be the most important variable for predicting GPP at all sites, contrary to TA and VPD. The Belgium and Italian sites show a correlation of 0.51(0.55) for TA and 0.38(0.48) for VPD, respectively. Whereas in the French site, the TA correlation of 0.55 exceeds the VPD correlation of 0.38. Consequently, the GPP reduction varies along the different sites. This study shows the necessity of long-term monitoring datasets to understand better the O3 impacts at several ecosystems combined with process-based models. 
Global and Regional Numerical Modeling of Water and Ammonia Cycles on Jupiter
Authors: Lian Yuan , Guillot Tristan , Ingersoll Andrew , Li Cheng
Published: February 2023

Data analysis of Juno MWR instrument measurements of brightness temperature at six channels showed that ammonia vapor was depleted in the region between ammonia cloud base all the way down to 40-60 bars. The vertical extent of depletion is far greater than previous thought, which assumed that ammonia in the sub-cloud layers were well mixed. We use a state-of-the-art Global Circulation Model (GCM), JupiterMPAS, to investigate the physical and dynamical processes below the water cloud base in hoping to interpret water and ammonia abundances retrieved over a wide range of latitudes. Two mechanisms that may affect ammonia distributions have been examined: “mushball” microphysics and mesoscale circulations. JupiterMPAS model results show that: 1. the mushball microphysics is a viable method to produce ammonia depletion in the region above water cloud base; 2. the treatment of lower boundary conditions in the JupiterMPAS model can impact tracer distribution in the sub-cloud layers; 3. depletion of ammonia via strong mesoscale downdrafts is possible, but its effect on global ammonia distribution is very limited.
The influence of preparation obtained by the electropulse ablation method on the soil microbiota in soybean crops
Authors: Kravchenko Olha , Bilyavska Ludmila , Chobotar Viacheslav
Published: February 2023

A powerful factor in increasing the productivity of crop production, the potential of which is extremely underutilized, is the intensification of the development of agronomically useful groups of microorganisms. These groups of microorganisms increase the fertility of the soil due to their participation in the transformation of complex compounds of carbon, nitrogen, phosphorus, potassium and trace elements, converting them into available for plants forms. That is why it is extremely important for the agricultural producer to know the state of the soil microbiota in order to timely correct it and prevent crop productivity losses (Coban et al, 2022, De Corato et al, 2020).The purpose of the research was to determine the composition of ecological and trophic groups of soil microbiota in soybean crops after seed treatment with a drug whose components were obtained by the method of electropulse ablation (Kravchenko et al, 2021). To compare the effect of the preparation, the other part of the soybean seeds was treated with the chemical pesticide Maxim XL (active substance - Fludioxonil + Metalaxyl-M). As a control, seeds without etching were used.As a result, it was established that the amount of ammonifiers in the variant with preparation was 1046 thousand CFU/g of soil, while in the variant without etching - 396.7 thousand CFU/g of soil, in the variant with chemical pesticide - 188.1 thousand CFU/g of soil. This may indicate a high content of organic matter in the soil, since under such conditions the ammonifying microbiota is the most numerous and taxonomically diverse.In the experimental sample, pedotrophic microorganisms were 2 times more than in the control and about three times more than in the variant with a chemical pesticide. Under optimal conditions in the soil, pedotrophs are the most widespread group of soil microorganisms, which adequately reflects the general development of microbiota in the soil and play a significant role in the formation of soil fertility.The number of phosphate-mobilizing microorganisms in the experimental version exceeded 2.8 times the number of corresponding microorganisms in the control and variant with Maxim-XL. The high number of this group of microorganisms makes it possible to reduce the application rate of phosphorus mineral fertilizers.Thus, the obtained results indicate a significant increase in the number and composition of various ecological and trophic groups of microorganisms with the use of drugs obtained by electro-impulse ablation methods.
Using a co-production approach to support effective application of S2S forecasts in Africa
Authors: Hirons Linda
Published: February 2023

Forecasts on sub-seasonal to seasonal (S2S) timescales have huge potential to improve early warning and anticipatory action ahead of high impact events. However, fully realising this potential predictability requires reliable forecasts that are communicated effectively so that they can support appropriate preparedness action. This study reflects on the African SWIFT (Science for Weather Information and Forecasting Techniques) S2S forecasting testbed which brought together researchers, forecast producers and forecast users from a range of African and UK institutions. The testbed used a co-production approach to pilot the provision of real-time bespoke S2S forecast products for applications. The S2S testbed supported decision-makers in a range of sectors and contexts. For example, informing food security decisions and hydropower energy planning in East Africa, supporting agricultural decision-making across West Africa, and, in health applications, increasing the lead-time for potential disease outbreaks. This study critically reflects on the benefits and challenges of the co-production process within the S2S applications context. Specifically, while having direct access to the real-time S2S data allowed user-guided iterations to products to make them more actionable for their specific context. Some key lessons for effective co-production emerged. First, it is critical to ensure there is sufficient resource to support co-production, especially in the early co-exploration of needs. Second, all the groups in the co-production process require capacity building to effectively work in new knowledge systems. Third, evaluation should be ongoing and combine meteorological verification with decision-makers feedback. Ensuring the sustainability of project-initiated services within the testbed hinges on integrating the knowledge-exchanges between individuals in the co-production process into shaping sustainable pathways for improved operational S2S forecasting within African institutions.
Lagrangian atmospheric transport of the smoke plume from the large Australian Wildfire Event of 2019/2020.
Authors: Curbelo Jezabel , Rypina Irina I.
Published: February 2023

The bushfires in Australia during the 2019/2020 season were particularly severe, leading to the creation of a plume of smoke that rose into the Lower Stratosphere and resulted in record levels of smoke concentration.  In early January 2020, the plume disperses into independent transport paths in the stratosphere. Following a Lagrangian approach, we study the three dimensional atmospheric transport in the region at this time to better understand the cause of the splitting, the subsequent transport geometry, and the influence of the plume buoyancy on its movement. Aided by the Finite Time Lyapunov Exponent tool, we identify Lagrangian Coherent Structures (LCS) which simplify the three-dimensional transport description and make possible the characterization of the smoke plume evolution. Our numerical modeling results were able to replicate the observed behavior of the smoke plume during the bushfires in Australia, including the splitting of the plume into multiple pathways. In the model, we found parcels trajectories with the same behavior as the observed plume, highlighted the contribution of the passive advection of the plume by the wind versus the buoyancy effect of hot smoke, delineated the plume into regions destined to different fates, and showed that the division of the main path was affected by an eddy.
Resurrecting lost forests – speleothems inform on environmental changes in northern Scotland during MIS 5e
Authors: Breitenbach Sebastian F.M. , Homann Julia , Couper Hamish , Fox Beth R.S. , Kwiecien Ola , Lawson Tim J. , Hoffmann Thorsten , Henderson Gideon M. , Atkinson Tim C.
Published: February 2023

Modern Northern Scotland is a largely barren landscape, with most of the natural temperate rainforest that covered the Atlantic side of Great Britain lost to active deforestation and overgrazing, mainly by sheep and deer (Shrubsole 2022). Pockets of relic temperate rainforest are reminders of the significant changes induced by the arrival of humans and their domestic animals. However, little is known about early Holocene and previous interglacial environmental conditions, and here we propose an unorthodox archive of natural vegetation cover of Scotland.We present a new U-Th dated speleothem from the previous interglacial (MIS 5e/Ipswichian) and use stable oxygen and carbon isotope ratios, in tandem with lignin, a biopolymer with three monomers, to gain insight into last interglacial environmental conditions in Assynt, NW Scotland. The lignin monomer ratio provides information about relative changes between gymnosperm vs. angiosperm plant communities, and thus on changes in vegetation (e.g., from pine forest to moorland or grassland).Flowstone TJL20080901 was found broken and recovered in 2008 from Rana Hole, a cave at 352 m above sea level overlain by heather moorland overlying blanket peat (Lawson & Dowswell 2022). Seven U-Th dates, analysed at Oxford University, show that this calcite flowstone was deposited between 127 and 119 ka BP during Marine Isotope Stage 5e, with an average growth rate between 20 and 40 μm/yr.We suggest that speleothem δ13C indicates local infiltration and vegetation and soil composition, whereas δ18O reflects the history (source, temperature, seasonality) of the moisture feeding the cave stream from which the flowstone was precipitated. The lignin composition directly relates to local vegetation cover.Our new multi-proxy record provides unique insights into environmental conditions in Assynt during MIS 5e, and the history of vegetation developing without human interference.ReferencesHomann et al. (2022) Linked fire activity and climate whiplash in California during the early Holocene. Nature Communications 13:7175Lawson T. J. & Dowswell P. N. F. (2022) Caves of Assynt (3rd edition). Grampian Speleological Group. Edinburgh, 211 pages, ISBN 987-1-7397635-0-3Shrubsole G. (2022) The lost rainforests of Britain. HarperCollins Publishers, 336 pages, ISBN 9780008527952
Stochastic simulation of daily precipitation extremes in West Africa
Authors: Bliefernicht Jan , Rauch Manuel , Maranan Marlon , Fink Andreas , Kunstmann Harald
Published: February 2023

West Africa is one of the most data-poor regions in the world. In-situ precipitation observations are not available for many sites or contain many data gaps, thus leading to uncertainties and biases in hydrological studies in this region. To address this fundamental problem, we present a straightforward stochastic approach based on turning bands to simulate daily precipitation fields. Our approach is based on meta-Gaussian frameworks that generate Gaussian random fields, which are transformed into "real-world" precipitation fields using transfer functions. The simulation approach is tested for multiple extremes (1991 – 2016) in the Ouémé river basin in West Africa using different model settings and the most comprehensive station-based precipitation dataset available for this region. The evaluation shows that our approach is a valuable tool for simulation of daily precipitation fields and clearly outperforms classical interpolation techniques (e.g., ordinary kriging). Moreover, the simulation method can be conditioned on observations, uses only a small set of parameters and is an efficient algorithm for ensemble generation of precipitation fields for ungauged areas and design events.  In our West African research projects FURIFLOOD, the precipitation simulations are used as input information for hydrological modeling to reconstruct observed flood events and to create improved hazard maps for this region. Overall, the application of this advanced technique contributes to a better understanding of precipitation uncertainties and to the provision of improved station-based precipitation products for this challenging region.   
Linking soil hydrologic and tree transpiration dynamics by dendrometer measurements
Authors: Metzger Johanna Clara , Schütt Alexander , Becker Joscha N. , Reisdorff Christoph , Eschenbach Annette
Published: February 2023

Trees in forests and urban environments are increasingly under pressure due to extended periods of drought in central Europe. At the same time, their transpiration performance is all the more important to counteract drought and heat. Defining drought itself, as well as trees’ physiological response strategies, can be closely linked to soil hydrological conditions. In a three-year field experiment with young trees of different species planted in different substrates (n = 3 substrates * 9 species * 5 repetitions = 135 trees) in Northern Germany, we found that soil hydraulic properties strongly affected tree vitality, and that the species’ reactions towards unfavorable conditions differed significantly. This might be due to species-specific transpiration regulation strategies under drought stress. In a second step, we now link tree diameter fluctuations, which have been shown to closely correlate with transpiration, to soil water conditions. To this end, subsets of trees were equipped with dendrometers – 15 trees of one species (Quercus cerris) in three different substrates (sand, planting substrate, and loamy silt) in the growing season of 2020, and 21 trees of seven different species (Amelanchier lamarkii, Carpinus betulus ‘Lucas’, Geleditsia traconathos ‘Skyline’, Liquidambar styraciflua, Ostrya carpinifolia, Quercus palustris, Tilia cordata ‘Greenspire’) in sand substrate in the growing season of 2021. The dendrometer measurements were partly combined with soil water tension measurements (2020: n=6, 2021: n=10). By comparing statistical characteristics of the time series, we want to (1) link soil water and transpiration dynamics and (2) differentiate this link for different substrates and species. Such, tree stem diameter fluctuations, coupling soil conditions and physiological properties, might provide insight into the effect of tree strategic responses to soil drought.
Three Hundred and Fifty Views on what the Natural Hazard Community should do to Support the Implementation of the SDGs
Authors: Malamud Bruce D. , Šakić Trogrlić Robert , Donovan Amy
Published: February 2023

We present the results of an NHESS (Natural Hazards and Earth System Sciences) 20th anniversary survey, in which 350 natural hazard community members responded to two questions: (Q1) “what are the top three scientific challenges you believe are currently facing our understanding of natural hazards” and (Q2) “what three broad step changes should or could be done by the natural hazard community to address natural hazards in achieving the Sustainable Development Goals”? We have analysed the data quantitatively and qualitatively. According to the 350 respondents, the most significant challenges (Q1) are the following (within brackets % of 350 respondents who identified a given theme): (i) shortcomings in the knowledge of risk and risk components (64 %), (ii) deficiencies of hazard and risk reduction approaches (37 %), (iii) influence of global change, especially climate change (35 %), (iv) integration of social factors (18%), (v) inadequate translation of science to policy and practice (17 %), and (vi) lack of interdisciplinary approaches (6 %). In order for the natural hazard community to support the implementation of the Sustainable Development Goals (Q2), respondents called for (i) enhanced stakeholder engagement, communication and knowledge transfer (39 %), (ii) increased management and reduction of disaster risks (34 %), (iii) enhanced interdisciplinary research and its translation to policy and practice (29 %), (iv) a better understanding of natural hazards (23 %), (v) better data, enhanced access to data and data sharing (9 %), and (vi) increased attention to developing countries (6 %). We note that while the most common knowledge gaps are felt to be around components of knowledge about risk drivers, the step changes that the community felt were necessary related more to issues of wider stakeholder engagement, increased risk management and interdisciplinary working.
A proposal for drilling “Geiseltal” – a near complete terrestrial section of the Eocene in Central Europe
Authors: Kaboth-Bahr Stefanie , Bahr André , Zeeden Christian
Published: February 2023

As the world warms due to rising greenhouse gas concentrations, the Earth system moves toward climate states without historic precedent, challenging societal adaptation. One way to investigate these unprecedented conditions is to study past climates and ecosystems that shar similarities to our current and future ones. One such period is the Eocene (~56 – 33 Ma), during which the climate changed from a hot-house to a greenhouse state, comprising a wide range of atmospheric CO2 concentrations. However, our knowledge of the Eocene climate evolution is incomplete because of a lack of terrestrial records covering the entire period. To address this gap in our understanding, we propose to obtain drill cores at Geiseltal in Eastern Germany as part of the International Continental Scientific Drilling Program (ICDP).This former lignite quarry is famous for its exceptionally well-preserved Eocene mammal fossils, but its potential as a climate archive has not yet been explored due to the lack of existing drill cores. By drilling a maximum of three cores, we aim to create a spliced 100-120 m long record comprising the entire Eocene archived in Geiseltal as an alteration of lignite seems intercalated with fluvial strata. High-resolution, multi-proxy analyses of the obtained sediments will allow to generate a unique record of (sub)orbital climate variability under various atmospheric greenhouse gas concentrations. The integration of newly developed paleoclimate records with the existing paleoecological data will further help to inform how the terrestrial ecosystems reacted to long-term as well short-term changes, e.g., during hyperthermals. To advance this project, we welcome scientific input from a wide range of disciplines (e.g., stratigraphy, sedimentology, paleolimnology, paleobotany, paleontology, and organic/inorganic geochemistry) as well as are actively seeking interested groups and individuals to collaborate with us on this project.
Health impacts of wildfire smoke in the Arctic
Authors: Silver Ben , Arnold Steve , Emmons Louisa , Reddington Carly , Conibear Luke
Published: February 2023

Climate change has increased the vulnerability of boreal forests and grasslands to wildfires. An increase in high-latitude wildfires has resulted in the deterioration of air quality, particularly in Western Siberia, where PM2.5 levels have increased at >1 µg m-3 year-1 during 1998−2020. Arctic wildfire carbon emissions have doubled during the last 20 years, and in Siberia they have shifted northwards. Using fire air pollutant emissions data from the Quick Fire Emissions Dataset (QFED), we create two emissions scenarios for Arctic Council member nations, with and without wildfires. PM2.5 is simulated for the two scenarios using the Community Earth System Model, which we evaluate using in-situ measurement data, finding a large negative bias in wildfire plumes. To correct this underestimation we use a high resolution PM2.5 reanalysis dataset, improving agreement with observations. Bias-corrected scenarios are used to estimate air quality degradation and resulting health impacts due to Arctic Council nation wildfires across the Northern Hemisphere high- and mid-latitudes for the period 2001-2020. We use the Global Exposure Mortality Model to estimate the health impacts of chronic exposure to Arctic wildfire-attributed PM2.5­. We find that health impacts are highly variable, with 25,000−55,000 premature deaths yearly, with most of the health burden falling on nations outside the Arctic Council, particularly China, due to transboundary transport of Siberian wildfire PM2.5. Health impacts have decreased during our study period partly due to the northwards shift in wildfires.
Characteristics of saltwater wedge under the chalk cliffs of Sainte-Marguerite-sur-Mer (Normandy, France) using optical and geophysical methods.
Authors: Junique Thomas , Antoine Raphael , Costa Stéphane , Beaucamp Bruno , Guilbert Vincent , Ledun Cyril , Maquaire Olivier , Rejiba Faycal , Fauchard Cyrille
Published: February 2023

Saltwater wedge is a natural phenomenon defined as the displacement and retention of saltwater in a freshwater aquifer. This saline intrusion can modify the content of dissolved elements in coastal freshwater aquifers, which can have consequences for water use (drinking or agricultural), on the ecology, the environment, the erosion of coasts, and the stability of coastal structures.This study focuses on the integration and coupled interpretation of various geophysical and optical data obtained on the ground and by drone to evaluate the intrusion of seawater in a coastal chalk cliff in Sainte-Marguerite-sur-Mer in Normandy, France. The objective is to characterize the freshwater-saltwater interface and describe the internal structure of the formation. To do so, the combination of geophysical (Electrical Resistivity Imaging, ERI), aerial (visible and thermal infrared photogrammetry, IRT), and geotechnical (piezometers) methods was adopted.The ten ERI profiles (transverse and longitudinal to the cliff) allowed for the mapping of the electrical resistivity distribution. The novel contribution of this study was the highlighting of a marine intrusion under the chalk cliffs visualized using transverse ERI profiles implanted directly on the steep dip of the cliff. The use of a 30m deep piezometer positioned on the plateau of the cliff and intersecting the ERI profiles made it possible to constrain the resistivity values to the measured salinity values. The presence of this saltwater wedge was characterized by low resistivity values. The top of the cliff and the parts close to the outcrop showed significant resistivities, indicating a high level of potential damage (cracks in the outcrop, underground cavities). This allowed for the identification of a zone (about 10m before the main scarp) vulnerable to the risk of collapse.It has been shown that the difference in groundwater density leads to unstable conditions. We propose that the denser saline water covering the less dense freshwater creates a haline convection of the brackish waters at the base of the cliff and at the level of the rocky shore platform. The IRT was used to identify the wet areas of the cliff and the resurgences of the water table on the platform. Finally, all the data were grouped to propose a conceptual model of saline intrusion under the coastal cliffs.
Drinking-water supply sources and hydrological droughts: influence of tourism demand and reservoir availability on groundwater exploitation for the Rimini case study
Authors: Toth Elena , Neri Mattia
Published: February 2023

The analysis of the factors driving the exploitation of drinking-water sources is fundamental in the modelling and planning of water supply systems. To this end, it is important to assess the impacts of water scarcity, related to periods of hydrological drought, on the use of the available sources. This is of particular interest in touristic regions, where resource management must necessarily take into account also the significant seasonal fluctuation of urban demand.As part of the European project SIMTWIST (Simulating Tourism Water Consumption with Stakeholders), the study analyses the factors influencing both the demand for drinking-water supply of the city of Rimini and the apportionment of the supply among the different sources available to the water manager (RomagnaAcque-Società delle Fonti SpA). In fact, the city is supplied with both surface water, from the Ridracoli reservoir in the Apennines, and groundwater from well fields on the alluvial fans of the Marecchia and Conca rivers.The drivers include socio-economic variables (tourist attendance), climatic variables and hydrological availability. In particular, it is analysed how the exploitation of the groundwater source varies as a function of water availability at the Ridracoli reservoir, characterizing such availability through meteorological and hydrological drought indices computed on the upstream catchments.The analysis, in addition to confirming how the management of the resource cannot, in Mediterranean regions, disregard tourism factors, helps to understand the link between hydrological droughts, governing the availability of river-fed reservoir supply, and the choices made by water managers in the exploitation of the groundwater sources.
Quantifying the Impact of Modern Ice Mass Loss on Crustal Strain and Seismicity across Greenland and the European Arctic
Authors: Coulson Sophie , Hoffman Matthew , Dascher-Cousineau Kelian , Delbridge Brent , Bürgmann Roland , Carmichael Joshua
Published: February 2023

Ice mass loss from the Greenland Ice Sheet and Arctic glaciers has accelerated over the last three decades due to rapid changes in Arctic climate. This loss of ice from glaciated areas and redistribution of water across the global oceans creates a complex spatio-temporal pattern of crustal deformation due to the load changes on Earth’s surface. We test whether the resulting strain perturbations from this deformation are large enough to influence seismic activity in the Arctic on decade to century timescales. Using new ice-mass-loss estimates from radar altimetry for the Greenland Ice Sheet and model reconstructions of glaciers across the European Arctic, we predict gravitationally self-consistent sea level changes across the Arctic over the last three decades. These surface loads are then used as input for our deformation model, developed to calculate strain at depth within the crust, using a Love number formulation for a spherically symmetric Earth. Our global model captures both the near-field effects directly beneath ice centers and deformation across the sea floor, allowing us to fully quantify the spatio-temporal perturbations to the regional strain field created by glacial isostatic adjustment (GIA) processes. Using declustered earthquake catalogs of Arctic earthquake activity over the last three decades, we search for correlation between the earthquake record and our modelled strain perturbations. In particular, we focus our search along the Mid Atlantic Ridge and beneath Greenland. In the former, small magnitude GIA-related strains enhance or counteract rapid tectonic background loading, while in the latter intra-plate setting, GIA processes likely dominate the crustal strain field. While correlations over the last three decades may not be statistically definitive, this framework also allows for prediction of crustal strain patterns for future ice sheet scenarios, as ice mass loss from Greenland accelerates, and therefore predictions of the likelihood and potential geographic variability of climate-change-induced seismicity in the future.
N2O emissions from emission hotspots in agricultural soils – linking crop root growth and distribution with soil moisture and nitrate dynamics
Authors: Poultney Daniel Mika-Nsimbi , Liu Yujia , Ambus Per , Elberling Bo , Thorup-Kristensen Kristian , Müller Carsten W.
Published: February 2023

Agricultural soils are a major source of the potent greenhouse gas nitrous oxide (N2O). However, these emissions have high spatial variability and are highly heterogeneous in their distribution in agricultural landscapes. In Eastern Denmark, N2O “hotspots” or disproportionately high emission zones, have been observed in the vicinity of glacial depressions. These depressions form a topographical slope, where the base of the slope is typically inundated for 1-3 months over the winter and spring seasons. Preliminary work showed that the highest N2O emissions have been observed at the base of the slope, along the perimeter of the ponding zone of these depressions. In the present study we now aim to identify the mechanistic drivers of these N2O hotspots.N2O emissions were measured weekly at four positions along a gradient from upslope to the centre of a glacial depression over a winter to spring wheat growth season, at a farm in Eastern Denmark. The potential driving factors were  measured weekly along the slope: soil moisture at depths of 10 cm, 20 cm and 100 cm; soil solution nitrates and DOC at these same depths; and root growth using photographs at different depths using minirhizotrons to a depth of 100 cm. Additionally the groundwater level was monitored using a well and pressure logger. To underpin the results of this core site, further N2O measurements and soil samples were taken along the slope of three additional glacial depressions nearby with comparable topography and soil properties .The N2O emissions were found to be highest at the base of the slope, around the perimeter of the depression. We were able to demonstrate that root growth is directly linked to the moisture regime and thus the overall fate of nitrate and N2O emissions.Given the locally high N2O emissions of these hot spots, this study provides a lens into an important source of N2O emission heterogeneity in the Danish agricultural landscape.
Unique salt intrusion observations during the severe drought of 2022
Authors: Wegman Tess , Pietrzak Julie , Horner-Devine Alexander , Dijkstra Henk , Ralston David , Kranenburg Wouter
Published: February 2023

Salt intrusion is becoming an urgent problem in many deltaic areas due to the increasing probability of droughts under climate change. Sea level rise is an additional consequence of climate change, exacerbating salt intrusion worldwide. Extensive field observations during extreme droughts are rare. One of the worst droughts ever experienced took place in Europe in 2022. 

Here we present unique observations carried out during a 17 week period in the summer and autumn of 2022 in the Dutch Rhine-Meuse Delta. The dataset includes measurements of velocity and salinity around the mouth of the Rhine River and salinity measurements at numerous locations within the estuary. Apart from the fixed measurement locations, a number of ship-borne surveys were carried out during the campaign period. 

The ship transects are analysed to evaluate the internal flow structure compared to normal and high discharge conditions. The ship transects show a vertically well-mixed structure in the shallower sections of the upstream estuary. A salt-wedge structure is still present in the downstream estuary as found in a normal year, however, instead of fresh water in the surface layer as found in a typical year, the upper layer has a salinity of up to 8 PSU.  

We will present the first analysis of this dataset, exploring how the stratification alters during the drought and impacts the salt transport mechanisms in the estuary. Furthermore, our aim is to analyse the coupling between the Rhine Region of Freshwater Influence and salt intrusion length, under varying forcing conditions by means of combining the offshore stations and the inland salinity stations. 
Detections of high peak current lightning and observations of Elves
Authors: Bjørge-Engeland Ingrid , Østgaard Nikolai , Marisaldi Martino , Luque Alejandro , Mezentsev Andrey , Lehtinen Nikolai , Chanrion Olivier , Neubert Torsten , Reglero Victor
Published: February 2023

Elves are produced when electromagnetic pulses from lightning interact with the lower parts of the ionosphere and are observed from space as expanding rings of light in the UV and visible optical bands. Elves are known to be associated with high peak current lightning. Using data from the Modular Multi-spectral Imaging Array (MMIA) instrument of the Atmosphere-Space Interactions Monitor (ASIM) payload, we search for observations of Elves when high peak currents (>70 kA) are detected by the global ground-based lightning detection network GLD360. We identify two types of events; high peak current detections associated with Elves, and high peak current detections not associated with Elves. To understand why some high peak current discharges do not generate observable Elves, we explore the number of lightning discharges and their peak currents leading up to the events. Preliminary results indicate that for current pulses with peak currents below 100 kA we observe a significant number of Elves, but this quantity depends on the lightning activity within 5 minutes before. Current pulses with peak currents above 120 kA nearly always produce Elves, regardless of the preceding lightning activity.  
On the Speed of Interplanetary Shocks Propagating through the Magnetosheath
Authors: Moissard Clément , Bernal Axel , Savoini Philippe , Fontaine Dominique , Modolo Ronan , David Vincent , Michotte de Welle Bayane
Published: February 2023

Interplanetary shocks are some of the main drivers of geomagnetic storms. Before they can impact the geomagnetic environment, they propagate through the magnetosheath where their properties and geometry can be modified. What is the velocity of interplanetary shocks propagating through the magnetosheath? Previous numerical simulations and observations have given a wide range of apparently contradictory answers to this question, but they seem to all agree that interplanetary shocks generally slow down as they enter the magnetosheath: the interplanetary shocks’ velocity in the magnetosheath have been reported to be between 0.25 and 0.93 times their velocity in the solar wind. In this work, we offer two competing simple models to predict the propagation velocity of shocks through the magnetosheath. These models are applied to a list of shocks detected by currently operational spacecraft (e.g. Wind, MMS) as well as to results obtained from a hybrid PIC simulation. We show that our models both reconcile previous results and imply that interplanetary shocks could - in certain space weather-relevant situations - travel faster in the magnetosheath than they did in the solar wind. 
Precipitation of accelerated electrons at Mars
Authors: Akbari Hassanali , Fowler Christopher , Andersson Laila
Published: February 2023

Accelerated electron populations observed in the nightside ionosphere of Mars are investigated using measurements obtained by MAVEN’s Solar Wind Electron Analyzer. The measurements are of particular interest as they extend to altitudes as low as 130 km and to regions characterized by strong crustal magnetic fields, allowing us to investigate the evolution of the electron distributions in the complex crustal fields and determine the rate by which the accelerated populations precipitate into the Martian upper atmosphere.The majority of the observed accelerated electrons are trapped in the crustal fields, bouncing between mirror points, presumably drifting across magnetic field lines, but without instantaneous access to the collisional atmosphere. The average energy flux of these electrons is significant when compared to that of the much more common ‘unaccelerated’ sheath electrons. Considering that the Martian crustal magnetic fields do not provide a closed path for drifting particles, the trapped electrons are bound to exit the crustal fields and either precipitate into the atmosphere or escape. Currently, we estimate that, despite their low detection rate (< 1%), the accelerated electrons account for about 10% of the total energy that is deposited into the nightside ionosphere by electron precipitation. Further, the peak energy of the accelerated electrons is generally found in the range of tens to hundreds of eV, consistent with the energy range previously suggested for the generation of discrete aurora emissions observed on Mars.
Evaluating the risk of tipping cascades through the strength of the bipolar seesaw
Authors: Montoya Marisa , Jackson Laura C. , Alvarez-Solas Jorge , Robinson Alexander
Published: February 2023

The potential for the coupling between tipping elements leading to the occurrence of tipping cascades is of deep concern. One major tipping cascade that is often invoked results from coupling between the Greenland ice sheet, the Atlantic meridional overturning circulation (AMOC) and the Antarctic Ice Sheet (AIS). Melting of Greenland could contribute to a weakening of the AMOC, which would then result in a decrease in the northward heat transport in the Atlantic Ocean, causing warming of the Southern Ocean around Antarctica. This idea is supported by the evidence provided by ice-core records and models of different complexity suggesting that, during the last glacial period, the Southern Ocean acted as a heat reservoir which dampened and integrated in time the North Atlantic abrupt climatic variations through the bipolar seesaw. However, it has been argued instead that the heat reservoir to the Atlantic meridional heat transport involved does not lie in the Southern Ocean but north of the Antarctic Circumpolar Current, and transmitted via the atmosphere to the interior of Antarctica. Determining the ultimate heat reservoir in the sense of the strength of the Southern Ocean heat reservoir is critical to evaluate the risk of a tipping cascade.  Here we will investigate how model resolution affects the strength of the bipolar seesaw and the ultimate heat reservoir involved in this mechanism by using two different model horizontal resolution versions (0.25 and 1 degree, respectively) of the HadGEM3-GC3-1 model in simulations with a reduced AMOC in response to freshwater forcing in the North Atlantic.
Simulations of SEP events with the novel PARADISE+ICARUS model
Authors: Husidic Edin , Wijsen Nicolas , Baratashvili Tinatin , Poedts Stefaan , Vainio Rami
Published: February 2023

Coronal mass ejections (CMEs) are large eruptions of solar mass and
magnetic field into space, representing the most violent manifestation
of solar activity. During their propagation, fast CMEs generate shock
waves that can efficiently accelerate so-called solar energic
particles (SEPs) to energies of deka-MeV and beyond. Since SEPs can
pose a significant hazard to astronauts and spacecraft, there is great
interest in numerical simulations that can realistically model and
predict the acceleration and transport of SEPs. We simulate SEP events
in the inner heliosphere with the novel coupled model PARADISE+ICARUS.
Using the MPI-AMRVAC-based ICARUS code that implements adaptive mesh
refinement, we generate realistic background solar wind configurations
at heliocentric distances from 0.1 au onward and include superposed
transients. To study the propagation of SEPs, we use the PARADISE
(PArticle Radiation Asset Directed at Interplanetary Space
Exploration) code. PARADISE takes solar wind configurations obtained
from ICARUS as input to calculate energetic particle distributions by
solving the focused transport equation in a stochastic manner. Recent
results of these simulations are presented.
Roles of law and planning for a sustainable approach: institutional profiles
Authors: Bevilacqua Marco
Published: February 2023

Recent climate, health and economic emergencies have put a strain on sustainable transition national and supranational systems and it has been showed how much human beings depend on the environment. In this context, it is relevant to address which role public law should embody in climate change adaptation. It is of course a complex question and it has at least two sides: public law could be an essential vehicle for implementing adaptation policy across a range of sector and a source for providing policies aimed at changing behaviour.For instance, in the field of climate change, the regulatory problem arises in terms of good administration/governance. Public law could also, however, be interpreted as a tool for communicative action that may enhance co-operation in the municipal organization. In fact, the local government and private actors play an important role in the implementation of climate change adaptation. It follows that law-making is one of the key institutions providing the means to set priorities for climate action.Being more specific, policy intervention sets objectives; the law (or regulation) tells how to reach them, determining the procedures that must be respected. Thus, policies are more widespread internationally, while laws at the domestic level.Using the words of the HRH Sultan Azlam Shah, former Chief Justice of Malaysia, «legal principles and rules help convert our knowledge of what needs to be done into binding rules that govern human behaviour. Law is the bridge between scientific knowledge and political action» (23 August 1997). In order to catch the characteristics of the two tools in question it will be measured the effectiveness of non-binding solutions, such as the Glasgow Climate Pact (COP26), and legislative tools as the European regulation n. 2021/1119 on green deal. The expected results of the study are a lack of effectiveness of planning tools at an international level, while local legislation keeps exceptional leeway for local administrators, free not to proactively involve stakeholders.It will also address the relationship between national and supranational level’s planning: for these purposes, it will be relevant to analyse, in a comparative perspective, the impact of the Italian Piano per la Transizione energetica and Spanish legislation 2021/7, on Cambio Climático y Transición Energética.
Short-term temperature variability in regional climate models in Europe
Authors: Sedlakova Klara , Krauskopf Tomas , Huth Radan
Published: February 2023

While long-term changes in mean values and extremes of temperature have been analysed from all possible points of view, changes in temperature variability have received far less attention. Trends in variability are, however, important, among others because their interaction with trends in mean values determines the degree with which extremes would change. For a reliable estimation of future changes of variability, it is therefore crucial that climate models simulate its characteristics correctly. This contribution presents the analysis of 4 short-term (i.e. intra-seasonal) variability measures of daily mean temperature in outputs of regional climate models driven by a reanalysis. The utilized measures of variability are standard deviation, the range between the 90th and 10th quantile, one-day lagged temporal autocorrelation, and mean absolute value of day-to-day change. The ability of twelve regional climate models from Euro-CORDEX initiative driven by the ERA Interim reanalysis to simulate the temperature variability characteristics was examined over Europe for all climatological seasons in the period from 1989 to 2008. The temperature variability in the RCMs was validated against the driving ERA Interim reanalysis and station data from the ECA&D.
Global hydro(geo)logical modeling: are we missing an uncanny valley?
Authors: Moosdorf Nils , Reinecke Robert , Befus Kevin
Published: February 2023

The spatial and temporal resolution of global-scale hydrological modeling has enormously increased in recent years. Outputs are becoming available at spatial resolutions of 1x1 km, showing regional structures and changes, often in beautiful figures and large datasets covering the entire globe. The complexity of the underlying models has increased in parallel, as did the amount of input data. Model outputs start more and more to look like the actual planet.If humanoids start to look more and more like actual humans, an adverse emotional reaction can be seen in humans. In robotics and other disciplines, the term “uncanny valley” was coined for this phenomenon of the creepy impression that humanoids that are too human-like leave on humans.The increasing resolution of global hydro (geo)logical modeling outputs is partly mirrored by the increasing resolution of input data, e.g., satellite-derived climate data or vegetation information. However, input data based on in-situ observations can remain limited in resolution and remain highly uncertain. In addition, higher resolution models do not necessarily entail that our process understanding has improved. Here, we review and analyze the primary input data of global hydro(geo)logical models, identify critical datasets and discuss the implications of the reliance on these datasets for modern hydro(geo)logical model results. Moreover, we discuss if results that look more and more like the real planet should lead to skepticism in their interpretation similar to the emotional reaction to the uncanny valley in robotics.  