bluuebunny/crossref_metadata_2025 huggingface dataset:
Towards assimilating SAR data into an anisotropic model of an underground aquifer
Authors: Salehian Ghamsari Sona , Van Dam Tonie , S. Hale Jack
Published: February 2023

In this study, we aim to shed light on the feasibility of assimilating synthetic aperture radar (SAR) data into a partial differential equation-based model of a poroelastic homogeneous aquifer with anisotropic hydraulic conductivity (AHC).Although other authors [1] have considered the problem of assimilating SAR data into a poroelastic model that uses an inhomogeneous random field model for the hydraulic conductivity, to the best of our knowledge this is the first study to consider assimilating SAR data into a poroelastic model with AHC.Our study is inspired by the work of [2] where an aquifer test is performed on the Anderson Junction aquifer in southwestern Utah. Due to the inherent preferential direction of the fractured sandstone at the Anderson Junction site, the ratio of hydraulic conductivity along the principal axes can be on the order of 24 to 1.We build an anisotropically conductive poroelastic finite element model of the Anderson Junction site that can predict the coupled fluid flow and mechanical displacements. Our results show that the effective elastic response of the aquifer on the Earth’s surface has an anisotropic nature driven by the underlying anisotropy in the fluid problem, even when the elasticity problem is assumed to be isotropic. We interpret these results in the context of using SAR data to improve the characterization of aquifer systems, like the Anderson Junction site, with strongly anisotropic behavior.[1]      A. Alghamdi, “Bayesian inverse problems for quasi-static poroelasticity with application to ground water aquifer characterization from geodetic data,” Thesis, 2020. doi: 10.26153/tsw/13182.[2]      V. M. Heilweil and P. A. Hsieh, “Determining Anisotropic Transmissivity Using a Simplified Papadopulos Method,” Groundwater, vol. 44, no. 5, pp. 749–753, 2006, doi: 10.1111/j.1745-6584.2006.00210.x.
Climate change and subsurface urban heat island: ground surface, well temperature and surface air temperatures correlation in the city of Padova, Italy
Authors: Di Sipio Eloisa , Cenni Nicola , Galgaro Antonio
Published: February 2023

The geothermal heat available in urban environments is becoming increasingly interesting for its possible use as geothermal resource available at shallow depth beneath cities.This heat is mainly composed of the natural thermal background regime of the area of interest, the anthropogenic effect due to the urbanization process and the contribution due to the global warming. To be able to differentiate between these contributions provides a better understanding on how the urban heat resource could be used and managed.In detail, global climate warming has a direct consequence in the increase of surface air temperature over time affecting, at local scale, the heat energy exchanges between the air-ground interface. The air temperature fluctuations can penetrate several meters deep into the subsurface raising the ground surface temperatures and, consequently, the mean annual temperature of shallow aquifers. A detailed analysis of temporal series of air, ground and shallow depth ground temperature data is expected to show this behaviour.The city of Padova and its surroundings, located in the north-east of Italy, were selected as case study area. Here, starting from a comprehensive analysis of surface air temperature variation in the last 60 years, the local climate change was tracked. The correspondence between increase temperature on surface and underground was researched using at first underground temperature profile data collected in surface groundwater wells in urban and agricultural areas. The preliminary results confirm the influence of air temperature variation, affected by global warming, on shallow depth ground. Next step consists in the analysis of underground temperature profile variations over approximately 100 m depth in a geothermal borehole installed in the city centre, to assess the contribution of the climatic temperature to the background thermal regime and anthropogenic heat effect.
Demystifying urbanization and migration interaction pathways – Evidences from 80 cities of India.
Authors: Kumar Ratan , Mann Deepika , Shukla Roopam
Published: February 2023

Rapid rate of urban growth are being reported, urbanization is recommended, but at what environmental, health, and equity costs? Phenomena such as the  Urban heat island are resulting in  increased risk of heat-related mortality and morbidity, unequal benefits, and exclusionary planning. It is becoming increasing critical that we understand and address the challenges arising due to unplanned and rampant urbanization. The current study aims to characterize SUHII in 80 cities of India and correlate its impacts on migration using Google Earth Engine. 4 different pathways in which migration and urbanization are summarized based on the evidences gathered from the remote sensing based analysis. The results of the study will assist in deriving quantitative evidence will notably support the design of urban risk reduction practices at a pan- India level.
Characterization of blowing snow aerosol events in the central Arctic
Authors: Bergner Nora , Beck Ivo , Pratt Kerri , Mirrielees Jessica , Creamean Jessie , Frey Markus , Heutte Benjamin , Angot Hélène , Arnold Steve , Uin Janek , Springston Stephen , Matrosov Sergey , Laurila Tiia , Jokinen Tuija , Quéléver Lauriane , Pernov Jakob , Gong Xianda , Wang Jian , Schmale Julia
Published: February 2023

Sea salt aerosols play a critical role in aerosol-radiation and aerosol-cloud interactions. Salty blowing snow has been hypothesized as an important source of sea salt aerosol in polar regions. The snow over sea ice can become salty by upward brine migration or deposition of sea spray produced from leads or transported from the ice edge. Wind-driven resuspension and sublimation of the snow is hypothesized to leave salty aerosol particles behind. Our understanding of aerosol emissions from blowing snow is based mainly on modeling studies, and direct observations to validate this process are sparse. The year-long Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition, with its integrated measurements and sampling of frequent winter storms, is well suited to enhance our understanding of coupled Arctic system processes. Here, we focus on the impact of blowing snow and high wind speed events on aerosol number concentrations, size distributions, optical properties and cloud condensation nuclei (CCN) concentrations. Total aerosol number concentrations were significantly enhanced during high-wind speed periods, also concurrent with increased scattering aerosol coefficients and CCN concentrations. We further present a process-based characterization of the blowing snow events during MOSAiC and identify the influence of environmental variables on aerosol emissions. Our observations provide new insights into wind-driven aerosol in the central Arctic and may help to validate modelling studies and inform parameterization improvement particularly with respect to aerosol direct and indirect radiative forcing.
Deriving mixing ratios of heavier neutral species in Saturn's ionosphere from light ion measurements and helium chemistry
Authors: Dreyer Joshua , Vigren Erik , Johansson Fredrik L. , Waite J. Hunter
Published: February 2023

Helium ions, He+, react only slowly with molecular hydrogen. A consequence of this is that He+ ions produced by, for example, photoionization of He in H2-dominated ionospheres, such as those of Jupiter and Saturn, can have principal loss mechanisms other than through reactions with molecular hydrogen even if the other reactants prevail in rather small volume mixing ratios. The Ion and Neutral Mass Spectrometer (INMS) onboard the Cassini mission operated in open-source ion mode during a few of the passages through Saturn’s upper atmosphere throughout the proximal orbits in 2017. Due to the high spacecraft velocity, exceeding 30 km/s, the retrieval of ion number densities was limited to light ion species with masses (for singly charged species) of < 8 Da. Direct measurements of mixing ratios of neutral species heavier than helium (such as H2O, CH4, NH3, N2,CO2 and CO) in Saturn's equatorial ionosphere are sparse and their retrieval was in part complicated by adsorption effects.We seek to make an independent estimate of the mixing ratios of volatiles other than H2 and He by making use of a simple model focusing on the production and loss balance of helium ions. We first consider two models to estimate the local production rate of He+ from the measured density profiles of He and H2 and show that these give estimates in reasonable agreement with each other. Then we show that the calculated concentration of He+ exceeds the observed values by up to two orders of magnitude if we only account for the loss of He+ ions through reactions with molecular hydrogen. We take this as a strong indicator that the principal loss mechanism of He+ in Saturn’s ionosphere is through reactions with other species than H2, whose overall mixing ratio is denoted fX.  Based on the assumption of photochemical equilibrium at altitudes below 2500 km, we can then proceed by estimating fX to closest approach for Cassini's proximal orbits 288 and 292. Our derived mixing ratios for the inbound part of orbits 288 and 292 are in reasonable agreement with the direct measurements from INMS around closest approach and subceed them at higher altitudes. Comparisons with results from other studies potentially suggest an increased water influx around equatorial latitudes.
On the initialisation of ice sheet models: equilibrium assumptions, thermal memory, and present-day states
Authors: Bernales Jorjo , Berends Tijn , van Calcar Caroline , van de Wal Roderik
Published: February 2023

A significant portion of the spread in future projections of ice sheet volume changes is attributed to uncertainties in their present-day state, and the way this state is represented in ice-sheet models. The scientific literature already contains a variety of classic initialisation approaches used by modelling groups around the globe, each with its own advantages and limitations. We propose a generalised protocol that allows for the quantification of the impact of individual initialisation choices, such as steady-state assumptions, the inclusion of internal paleoclimatic thermal signals, sea level and glacial isostatic effects, and calibration methods. We then apply this protocol to an ensemble of multi-millennia model spin-ups of the present-day Greenland and Antarctic ice sheets and show the importance of the choices made during initialisation.[This abstract is a companion to “Sensitivity of future projections of ice sheet retreat to initial conditions” by Berends et al. We hope that, if both abstracts are lucky enough to be accepted, the conveners can program the two talks in sequence.]
Continuous high-resolution glider observations of methane following the Nord Stream leaks
Authors: Mohrmann Martin , Queste Bastien , Biddle Louise
Published: February 2023

After detonations on the 26th September, methane gas leaked at four locations from the damaged Nord Stream pipelines into the Bornholm Basin of the Baltic Sea and into the atmosphere. A permanent Ocean Glider Observatory is located about 20 km east of the leaks, providing continuous data from prior, during and after the incident. We responded quickly by deploying an additional glider with a methane sensor close to the northern leak sites. The glider sampled the methane concentrations for the following three months. During the first week of deployment, we observe an saturation of the methane sensor in the downstream direction of the leaks, indicating methane levels above 1 μM. Outside of the projected downstream advection zone, the methane concentrations are about 100 times lower initially (~10 nM), but quickly increasing as the methane polluted area grows by advection and mixing. A week later the methane is spread along our observation trajectory. About four weeks after the onset of the leaks, the methane levels dropped significantly below 1 μM and after 6 weeks, they stabilize at the initially observed background levels in most places, but occasional patches of increased concentrations, especially in direct vicinity of the leaks remain. Using an advection-dilution scheme in combination with a high resolution Baltic Sea analysis model, we predict the temporal and spatial evolution of methane levels in different basins of the Baltic Sea. Comparing the modelled methane levels with our observations, we estimate rates of atmospheric outgassing and bacterial breakdown.
Ionospheric Impact on GNSS Reflectometry in the Tropical Region: A Simulation Study with NEDM model
Authors: Moreno Mario , Semmling Maximilian , Hoque Mainul , Wickert Jens
Published: February 2023

The ionosphere is a layer of Earth's upper atmosphere that is ionized by solar radiation. It plays a crucial role in the propagation of Global Navigation Satellite System (GNSS) signals, as these signals pass through the ionosphere on their way from the GNSS satellite to the receiver. The irregularities in the ionospheric electron density may have a significant impact on the GNSS signals, causing delays and phase and amplitude scintillations.GNSS reflectometry (GNSS-R) is a promising technique for atmospheric sounding. Multiple studies have been successfully conducted in the recent decade by using GNSS-R ground-based, airborne and spaceborne data e.g., to estimate ionospheric disturbances from the reflected signals. However, further investigations are needed to precisely characterize ionospheric effects for GNSS-R altimetric applications.This study presents simulation results of ionospheric delay for reflection events in tropical regions. The first-order ionospheric effects are estimated along the ray paths by deriving the slant total electron content from the Neustrelitz Electron Density Model (NEDM). The geometry of the simulated events refers to reflectometry records of the SPIRE satellite constellation and the satellite navigation system GPS on 2021/03/01.Initial analysis has shown promising results. As solar activity increases (indicated by solar radio flux F10.7 index), an increase in the total ionospheric phase delay is evident.  Between 0h and 8h local time, there is a delay of 2 to 10 meters. For the time interval from 8h to 16h, the delay is from 14 up to 22 meters, with the maximum at noon. In the sunset period from 16h to 24h, the ionospheric delay reduces from 9 to 3 meters, respectively. The height above the Earth’s surface at which the highest amount of electron content is found along the ray path is ~290 km. This altitude corresponds to the F-region which has the highest concentration of free electrons. The analyzed events correspond to elevation angles from 5 to 30 degrees. The highest ionospheric delay is found at elevation angles between 10 and 20 degrees also depending on the local time.
Investigating the effect of temperature on growth and microbial biomass accumulation during winter
Authors: Gall Christoph , Fuchslueger Lucia , Schmidt Hannes , Söllinger Andrea , Borg Dahl Mathilde , Tveit Alexander , Sigurdsson Bjarni , Eichorst Stephanie , Roller Ben , Richter Andreas
Published: February 2023

It is well documented that microbial biomass increases during winter in cold mountain or tundra ecosystems, but the cause and mechanism of such accumulation is unclear. Results from a grassland in Iceland demonstrated that the microbial biomass carbon (MBC, measured by the fumigation-extraction method) increased in winter, while microbial DNA content remained constant. We thus hypothesized that this accumulation of microbial biomass during the cold season is driven by the decrease in temperature, that increases the carbon storage of individual cells, but not by an increase in microbial cell numbers.To test this hypothesis, we conducted a laboratory incubation experiment with soils from a grassland in Iceland sampled before the onset of winter in early October (around 9 °C). We then exposed the soils to decreasing temperatures (0.5 °C, 3 °C, 6 °C and 9 °C) over five months. We analyzed microbial biomass carbon (MBC) and quantified the DNA content. Over the course of five months, we found higher MBC values at cool temperatures compared to warm conditions. As expected, cooling did not affect the DNA content, leading to a significantly higher MBC to DNA ratio when soils were incubated at 0.5 °C compared to 9 °C. This indicates that numbers of microbial cells did not change across temperatures, but that microbes at lower temperatures stored more carbon. We also found similar patterns in soils collected at different time points in the field. Furthermore, we estimated microbial DNA production, i.e., growth rates, by measuring the incorporation of 18O from labelled water into DNA. We observed lower microbial growth rates under field conditions in winter, indicating that increasing biomass carbon was not due to increased growth and that growth and turnover was balanced at all temperatures. Instead, we suggest that carbon uptake (which was decreased at lower temperatures) was less affected by cold temperatures than growth, so that microbial carbon could accumulate. We also verified this pattern in growth and carbon uptake rates with decreasing temperatures in the laboratory incubation experiment.Decreasing growth (cell division) and turnover rates with decreasing temperatures, at a lower but sustained carbon uptake rate, suggest that the cell size of soil microorganisms may increase when exposed to cooling. We will show and discuss first results from measurements with a suspended microchannel resonator (SMR), that, together with microscopic imaging allows to assess the mass (size) of individual cells of microorganisms at different temperatures. 
Influence of tectonic deformation on the mechanical properties of calcareous rocks: drawbacks of the non-destructive techniques
Authors: Mammoliti Elisa , Gironelli Veronica , Jablonska Danica , Mazzoli Stefano , Ferretti Antonio , Morici Michele , Francioni Mirko
Published: February 2023

Discontinuity surfaces are well known to influence the mechanical behaviour of rocks under compression. Non-destructive techniques, such as ultrasonic pulse velocity and sclerometers, are increasingly used to estimate uniaxial compressive strength of rocks. In this study, several core samples derived from the doubling works of the railway network near Genga (Marche Region, Central Italy) were analysed in order to assess the influence of the structural geological context (proximity to folds, faults etc.) and tectonic deformation on rock strength. Tests were conducted in rock specimens through: i) conventional uniaxial compressive experiment, ii) non-destructive rebound-based methods such as Schmidt Hammer and Equotip  and iii) ultrasound. In this way, it was possible to make a critical analysis of the use of these techniques in the estimation of the uniaxial compressive strength (considering also information about discontinuity type, orientation and nature of the filling). Finally, a petrographic analysis using optical microscope has been undertaken as a support to the observations derived from the analysis at the sample scale. The results indicate that there are two main factors influencing the strength at the scale of the specimen. The first and most decisive factor is the presence of natural pre-existing fractures. The second is the tectonic deformation ratio: the greater the deformation is, the little the strength. Furthermore, through the combined use of uniaxial compressive experiment, non-destructive rebound-based methods and ultrasounds it was possible to highlights the advantages and limitations of each technique and define/propose new guidelines for their use. 
Investigating sub-seismic sedimentary intrusions in the Middle Jurassic to Lower Cretaceous Agardhfjellet Formation (Svalbard)
Authors: Ogata Kei , Weert Annelotte , Betlem Peter , Birchall Thomas , Senger Kim
Published: February 2023

Meso-scale (sub-seismic) sedimentary injectites are inferred to play an important role in controlling subsurface fluid flow as documented in many hydrocarbon plays at various scales. Detailed characterisation of such units, usually unresolvable at the seismic scale, can be directly achieved at outcrop scale. In this framework, two sedimentary injection complexes have been analysed in the middle Jurassic-lower Cretaceous Agardhfjellet Formation exposed at Deltaneset (central Spitsbergen) at different stratigraphic levels. The upper complex comprises two main isolated, decimetres-thick clastic dykes characterized by different orientation and consolidation, tapering out vertically (up- and downward) within a stratigraphic thickness and a lateral extension of more than 50 m and 200 m, respectively. The lower complex is coarser-grained, made up by a network of interconnected dykes and sills, branching off from isolated lenticular bodies, interpreted to be linked to seafloor extrusion structures (sand volcano). Petrographic and micromorphologic analysis were used to identify the possible source of the remobilized material for both the upper and lower complexes within the over- and under-burden formations. Our results reveal that such granular material is likely sourced by the underlying coarse-grained lithologies of the late Triassic to middle Jurassic Wilhelmøya Subgroup. The lower complex was firstly emplaced during the Late Jurassic at shallow burial conditions, while the upper complex developed at higher confinement pressure, probably during the Late Cretaceous, with the progressive reworking of the same granular material. Field data allow detailed characterisation of complex structural-stratigraphic architectures of sedimentary intrusions, which can be used to constrain their spatial-temporal relationships with subsurface fluid flow.
Exploring the variability of freshwater inputs from tidewater glacier-ocean systems in the Canadian Arctic Archipelago
Authors: Parrott Claire , Waterman Stephanie , Myers Paul , Bhatia Maya , Bertrand Erin , Hamilton Andrew , Burgess David , Noah Terry , Brossier Eric , Didier David
Published: February 2023

Tidewater glaciers, numerous in the Canadian Arctic Archipelago (CAA), are an important and dynamic source of freshwater to the Arctic freshwater system, with glacial inputs modifying ocean structure, stimulating vertical mixing, enhancing biogeochemical delivery near-terminus, as well as contributing to regional freshwater budgets, storage, transport and export. Despite their abundance, we lack important knowledge regarding glacier-ocean systems across the CAA, and these systems are often omitted in regional studies of freshwater transport or storage. In this study, we examine the nature and spatial extent of glacial meltwater influence on freshwater dynamics in Jones Sound, a tidewater glacier-rich region in the CAA. Our goals are to better understand the influences of glacier inputs on upper ocean water column structure and mixing processes near the glacier terminus, as well as the role of tidewater glaciers in the regional oceanic freshwater system. We use summertime,  near-shore  in situ observations at both glacierized and non-glacierized sites, collected using the sailing yacht Vagabond and local vessels operated by community members from Ausuittuq (Grise Fiord, NU) over a 4-year timespan. This novel dataset provides fjord-scale and interannual resolution of water column properties from glacier terminus to open ocean. Further, we employ a high-resolution regional model (Nucleus for European Modelling of the Ocean (NEMO) framework of the Arctic and Northern Hemisphere Atlantic at 1/12 degree resolution) to examine regional freshwater transport and storage. In this presentation we will present results detailing notable year-to-year and site-to-site variation in upper ocean structure at the glacierized sites.  These results suggest that there is important spatial and temporal variability of the influences of glacially-sourced freshwater to Jones Sound that should be considered in near-shore ocean functioning and the regional freshwater budget.
Analysis of extreme precipitation and wind at convection-permitting resolution
Authors: Cesarini Luigi , Fosser Giorgia , Dallan Eleonora , Marra Francesco , Martina Mario
Published: February 2023

Climate change and its repercussions on society are gathering interest among scientists from different fields. In particular, the observed temperature increase of the last decades is reason for concern given the resulting change in frequency and intensity of extreme events. In the next decades, global warming is expected to lead to a significant increase of short-lived high-intensity precipitation, which is likely to increase the risk for flash floods especially in urban areas, landslides, and debris flow. Moreover, the joint occurrence of intense precipitation and strong wind is particularly hazardous for the forested mountainous catchments. In fact, the extensive uprooting may strongly enhance the triggering of landslides and debris flows, thus leading to the formation of large woody debris, as seen during the Vaia extreme storm that occurred in 2018 in northeastern Italy.

In this context, the aim of our study is twofold: (1) evaluate the fields of hourly precipitation and wind from convection-permitting models (CPM) against observations from stations and reanalysis datasets at CP resolution; (2) applying common bias correction techniques (i.e., empirical quantile mapping), as well as deep learning algorithms, like convolutional neural networks, that are able to analyse non-linear spatial relationships along with the possibility to incorporate multivariable bias correction procedures. Preliminary results show a general good agreement between CP and observational datasets at CP resolution, which would eventually benefit the bias correction methods. A better modelling and understanding of the changes brought by climate change, could eventually lead to an improved design and more appropriate application of risk mitigation strategies.
Unconscious bias in academia: its effects in geoscience and space science research communities and call for actions
Authors: Kieokaew Rungployphan ,   IDEEA collaboration
Published: February 2023

Diversity in the workplace has several benefits including enhancing creativity and collective intelligence – both crucial for problem-solving and unfettered discoveries in scientific collaboration. Geoscience and space science are STEM research fields that attract people from diverse backgrounds across the globe; these research fields have implications far beyond the tackling of climate change issues. Whereas diversity has several benefits, the academic communities, particularly in geoscience and space science, have been demographically skewed. Moreover, discriminations, sexual harassments, and bullying are not unheard of. Unconscious bias deals with stereotyping based on several apparent attributes or more-implicit convictions, such as gender, sexual orientation, race, age, religion, political views, etc. Prejudice against minorities in academia is evidenced in demographic representation at all career stages and gender pay gaps, for instance. By compiling recent studies, I will present the effects of unconscious bias on common academic metrics and practices (e.g., h-index, citation, authorship, and peer-review) and career progression (e.g., progress evaluation and hiring process). As a part of the solution, some action plans by various institutions and local initiatives will be presented. This talk aims to raise awareness of the impacts of unconscious bias in academia, especially in the geoscience and space science communities, and call for collective efforts from local to institutional levels.
IEA Wind Task 51 Forecasting for the Weather Driven Energy System
Authors: Giebel Gregor , Draxl Caroline , Frank Helmut , Zack John , Möhrlen Corinna , Kariniotakis George , Browell Jethro , Bessa Ricardo , Lenaghan David
Published: February 2023

The energy system needs a range of forecast types for its operation in addition to the narrow wind power forecast. Therefore, the group behind the former IEA Wind Task 36 Forecasting for Wind Energy (running 6 years, from 2016-2021) has broadened its perspective on forecasting issues in part by reaching out to other IEA Technology Collaboration Programmes such as the ones for PV, hydropower, system integration, hydrogen etc. The three existing Work Packages (WPs) on NWP Improvements (WP1), Power and Uncertainty Forecasting (WP2) and optimal use of Forecasting Solutions (WP3), are complemented by thirteen work streams in a matrix structure. The three work packages span three distinct areas of challenge in forecasting for the weather driven energy system. The first area is the continuing effort to improve the representation of physical processes in weather forecast models through both new high performance initializations and tailored parameterizations. The second area is the heterogeneity of the forecasters and end users, the full understanding of the uncertainties throughout the modelling chain and the incorporation of novel data into power forecasting algorithms. A third area is representation, communication, and use of these uncertainties to industry in forms that readily support decision-making in plant operations and electricity markets. Task 51 will focus on facilitating communication and collaborations among international research groups engaged in the improvement of the accuracy and applicability of forecast models and their utility for the stakeholders in the wind industry, in the power sector and in the energy system. The first two activities of Task 51 were (1) a workshop in Dublin on the State of the Art and Research Gaps for Forecasting. The results of the workshop will be compiled into a journal article, and (2) the publication of the IEA Recommended Practice for the Implementation of Renewable Energy Forecasting Solutions as an open access book by Elsevier. Other planned activities include further workshops on seasonal forecasting with emphasis on Dunkelflaute, storage and hydro in May 2023, a workshop on minute-scale forecasting (2024), and a workshop on extreme power system events (2025). The results of these interactive workshops will be compiled into a journal articles. Additionally, the Recommended Practice on Forecast Solution Selection will be updated to reflect the broader perspective. Reference: Corinna Möhrlen, John Zack, Gregor Giebel (eds): IEA Wind Recommended Practice for the Implementation of Renewable Energy Forecasting Solutions. Elsevier, 348 pages, Nov. 2022. ISBN: 9780443186813. Download the individual chapters from https://www.sciencedirect.com/book/9780443186813/iea-wind-recommended-practice-for-the-implementation-of-renewable-energy-forecasting-solutions.
Increasing Arctic River Discharge and Its Role for the Phytoplankton Responses in the Present-day and Future Climate Simulations
Authors: Park Jung Hyun , Kim Seong-Joong , Lim Hyung-Gyu , Kug Jong-seong , Yang Eun Jin , Kim Baek-Min
Published: February 2023

With the unprecedented rate of Arctic warming in recent decades, the hydrological cycle over high-latitude landmass began to accelerate, which would lead to increased river discharge into the Arctic Ocean. However, the recent climate models that participated in Coupled Model Intercomparison Project 6 (CMIP6) tend to underestimate Arctic river discharge. This study elucidates the role of overlooked Arctic river discharge for the phytoplankton responses in present-day and future climate simulations. In the present-day climate simulation, the run with additional river discharge simulates the decrease in the spring phytoplankton. Freshening of Arctic seawater leads to high freezing point that increases sea ice concentration in the spring, eventually decreasing phytoplankton due to the less light availability. On the other hand, in the summer, phytoplankton increases due to the surplus of surface nitrate and the increase in the vertical mixing induced by the reduced summer sea ice melting water. In the future climate, the role played by additional input of freshwater is similar to the present-day climate. However, the major phytoplankton responses are shifted from the Eurasian Basin to the Canadian Basin and the East-Siberian Sea. This is mainly due to the shift of the marginal sea ice zone from the Barents-Kara Sea to the East Siberian-Chukchi Sea in the future.
Characteristics of Tropical cyclones in sub-seasonal forecasting with GloSea5: Predictability in extreme ENSO phases and a climate regime shift
Authors: Kim Taehyung , Kim Eunji , Lee Minkyu , Cha Dong-Hyun , Lee Sang-Min , Lee Johan , Boo Kyung-On
Published: February 2023

Tropical Cyclone (hereafter, TC), a most destructive weather phenomenon that causes enormous socio-economic damage, occurs around 25 times every year in the western North Pacific, of which Korea is directly or indirectly affected by about 3 to 4 TCs every year. Even if it is affected by a small number of TCs, the damage could be unimaginably large. To preemptively prepare and respond to TCs, predictability on the sub-seasonal to seasonal (S2S) time-scale, over two weeks to two months is being emphasized. In this study, the characteristics of TCs in sub-seasonal forecasting with the Global Seasonal Forecast System 5 (GloSea5) of the Korea Meteorological Administration (KMA) were assessed over the western North Pacific (WNP). The predictability of GloSea5 was examined for its ability to reproduce observed TC climatology as well as changes in TC genesis with the El Niño-Southern Oscillation (ENSO) and a 1998/1999 climate regime shift. GloSea5 showed skilful performance in simulating the frequency and genesis spatial distribution of TCs in climatology and both extreme ENSO phases. Synoptic fields related to TC genesis were also reasonably captured, despite some systematic biases in those. GloSea5 performed well in terms of characteristics of changes in TC genesis due to the climate regime shift. However, there were biases in TC frequency before the regime shift and in changes in TC-related environmental fields. This study implies that GloSea5, which has a good predictive skill for TC genesis over the WNP, can be used as an operational model for sub-seasonal TC forecasting, although it requires continuous improvements to reduce systematic errors
Turbulence Properties of Kilometer-scale Equatorial Irregularities as Deduced from Swarm Satellites LP Observations
Authors: Buchert Stephan C. , Aol Sharon , Sorriso-Valvo Luca , Jurua Edward
Published: February 2023

The ESA Swarm satellites have since year 2014 provided measurements of electron density at a frequency of 2 Hz and at times also 16 Hz corresponding to about 500 m along the satellite paths. Spectral indices, structure functions and scaling exponents of these 16 Hz density estimates were analyzed to study the F-region ionospheric irregularities at altitudes between about 425 and 510 km. The data were obtained during the period from October 2014 to October 2022.The Power Spectral Densities (PSDs) observed followed to a very good approximation a power law. The values of spectral indices p obtained showed a peak centered at around -2.5, located at the Equatorial Ionization Anomaly (EIA) belts. The largest contribution to the spectra came from in the South American-Antlantic-African longitudes and it was generally low in the Asian-Pacific region. The angle between the Swarm satellite orbital path and the magnetic field (∠(B, v)) was examined. The highest percentage of occurrence of ionospheric irregularities and the peak in spectral index was obtained for ∠(B, v) between 0° and about 40°. Over this range of angles PSD spectra steepened with increasing ∠(B, v) (p becomes increasingly negative), consistent with local anisotropic turbulence at scales of a few km. The probability distributions of density differences (structure functions) are non-Gaussian at all orders, similar to many other observations in space plasma. The scaling exponent function is non-linearly concave, which is usually taken as a sign of intermittency.
Satellite Data Intercalibrationof Ring Current Observations
Authors: García Peñaranda Marina , Shprits Yuri , M. Castillo Tibocha Angelica
Published: February 2023

The Earth’s ring current is a complex, dynamic system that plays an important role in geomagnetic storms. This ring-shaped current environment changes its structure and intensity on different time scales as a result from the incoming solar wind.  The different particle populations display very different behaviors, making it extremely hard to develop physics-based forecasting models for this environment.Satellite data provides electron point measurements that can be used to study the different physical processes occurring in the Earth’s magnetospheric ring current. However, in order to fully understand the particle dynamics and injection processes in this region, high temporal and spatial data resolutions are required.We tackle this issue by using a combination of electron-flux observations from different satellite missions and instruments in order to improve the global resolution of this dynamic environment by intercalibrating POES, GOES, THEMIS and RBSP. To illustrate a use for this combined data set, we present a global reconstruction of the ring current population and a comparison of the observed electron flux environment with a re-analysis of the ring current region.
Particle alignment during sedimentation – a 4D approach
Authors: Kühn Rebecca , Kilian Rüdiger , Lang Dustin , Morales Luiz , Grendal Ola , Stipp Michael
Published: February 2023

The microstructural evolution of clay-rich sedimentary rocks starts with the settlement and alignment of particles. With the accordance between shape preferred orientation and crystallographic preferred orientation (CPO) in the case of disk-like clay particles, the parallel alignment can be quantified measuring the clay CPO.In order to quantify the influence of the sedimentation conditions on the CPO of primary layering we performed sedimentation experiments combined with in-situ synchrotron diffraction measurements. The experimental procedure involved a sediment suspension drip inserted at the top of a 30 cm water column at regular intervals. The fluid in the column was either deionized water or seawater, and the sediment suspension contained either kaolinite with of disk-like particle shapes or a mixture of kaolinite and polycrystalline illite, the latter with more compact particle shapes. Time-resolved CPO development in the experiments was measured at ESRF, beamline ID22.The formation of a CPO is readily observed at the water-sediment interface with an initially higher CPO strength in deionized water experiments than in seawater. The resulting sediment shows a pronounced layering in both fluids when using pure kaolinite. In the layered sediments in deionized water the CPO strength varies strongly between different layers. At some measurement positions, a high initial CPO strength drops fast in the first 150 minutes, interpreted to result from dewatering-related reorganisation of the microstructure. A stable CPO strength can be observed after ~200 min. In the seawater experiments the CPO strength does not vary in different layers and increases slowly but constantly with time and overburden indicating a successive rotation of particles. CPO in kaolinite experiments is higher than in kaolinite + illite experiments as compact particles locally inhibit the alignment.The evolution of clay particle orientation and therefore microstructure can be quantified in space and time. It is suggested that the initial microstructure is crucial for the progressive development of the rock during diagenesis and hence e.g. resulting physical properties. 
Unravelling the thermochemical structure and evolution of cratonic lithosphere with multi-observable probabilistic inversions
Authors: Afonso Juan Carlos
Published: February 2023

The present-day thermochemical structure of the subcontinental mantle holds key information on its origin and evolution and informs exploration strategies, natural hazard management and evolutionary model of the Earth system. As such, unravelling the nature of the continental lithosphere, its modification through time and its interactions with the sublithospheric mantle and the atmosphere/hydrosphere constitute some of the main goals of modern geoscience. Despite its fundamental importance, imaging the fine-scale thermochemical structure of the lithosphere using indirect (remote) data is plagued with difficulties, which has traditionally left the analysis of xenoliths and xenocrysts as the only reliable approach.In recent years, however, ‘simulation-based’ inverse methods that integrate multiple geophysical and geochemical datasets within an internally- and thermodynamically-consistent platform have opened new and promising ways to address this ‘grand challenge’. In this presentation, I will discuss i) some recent progress, case studies and future directions on the mapping of the thermochemical structure of the continental lithosphere, and ii) their predictive power for the energy and critical minerals sectors and possible implications for planetary exploration in general.
Density-driven convection and chemical infiltration in saturated porous media
Authors: Hurtiš Radoslav , Guba Peter , Kyselica Juraj
Published: February 2023

Convection and chemical dissolution in porous media are observed in many hydrogeological processes such as seawater intrusion in coastal aquifers, CO2 sequestration in saline aquifers and heat transport in geothermal reservoirs. When a porous medium is infiltrated by a fluid contaminated with a reactive solute, convection is accompanied by dissolution of the porous matrix through chemical reactions between the solute and minerals contained in the porous solid, generating reaction products. Here we study how density-driven convection and reactive infiltration affect the transport of the solute and products in the porous medium. Convection and dissolution are modelled by coupled equations describing flow, transport of the solute and products, and mineral dissolution in a two-dimensional rectangular domain with a solute source located along half of the upper boundary. We quantify the average solute flux from the source in unsteady flows and analyze its development towards a steady-state value computed in [1]. Numerical experiments on the temporal development of convective flow and concentration fields are reported (see [2] for more details). The full numerical solutions are augmented with asymptotic analysis in a weakly convective and reactive regime performed in the limit of small Rayleigh and Damköhler numbers.Acknowledgement:This work was supported by the Slovak Research and Development Agency under the contract no. APVV-18-0308, and the VEGA project no. 1/0339/21 and the GUK project no. UK/355/2023.References:[1] van Reeuwijk, M., Mathias, S. A., Simmons, C. T., and Ward, J. D.: Insights from a pseudospectral approach to the Elder problem, Water Resources Research, 45, W04416, https://doi.org/10.1029/2008WR007421, 2009.[2] Hurtiš, R., Guba, P., and Kyselica, J.: Simulation of reactive groundwater flow and salinization in carbonate-rock aquifers, 2022 International Conference on Electrical, Computer and Energy Technologies (ICECET), Prague, Czech Republic, 20–22 July 2022, pp. 1–4, https://doi.org/10.1109/ICECET55527.2022.9872944, 2022.
Processes underlying barite formation in the Mediterranean: a record of marine microbial activity during sapropel deposition
Authors: Martinez-Ruiz Francisca , Paytan Adina , Monedero-Contreras Ricardo , de Lange Gert
Published: February 2023

Mediterranean sapropels represent an exceptional example of productivity fluctuations reconstructed from Ba proxies. They have been cyclically deposited in the Mediterranean by the combination of climatically induced increases in primary productivity and changes in bottom-water oxygenation. The main driver behind the deposition of sapropels was the monsoon-related freshwater inputs into the eastern Mediterranean in response to periodic northward shifts of the intertropical convergence zone (ITCZ) that resulted in increasing nutrient supply and subsequently enhanced productivity and Ba accumulation. In general, increasing Ba content in marine sediments has been interpreted as a direct indicator of marine primary productivity. However, the diverse processes involved in barite precipitation are still poorly investigated. For instance, types of productivity and modes of nutrient delivery to the photic zone have been poorly explored in terms of spatial variability across the Mediterranean during sapropel deposition, which is crucial for Ba proxies interpretation. Recent insights from experimental work, as well as observations from microenvironments of intense organic matter mineralization in the ocean water column have demonstrated the role of bacteria and extracellular polymeric substances (EPS) production in barite precipitation. Both bacterial cells and EPS provide charged surfaces that bind metals inducing mineralization, therefore, playing an essential role in promoting locally high concentrations of Ba leading to barite formation. This occurs through P-rich amorphous precursor phases, being phosphate groups in EPS, and bacterial cells the main sites for binding Ba. The ubiquitous presence of bacteria in aquatic systems, and in particular in the mesopelagic zone at depths of intense organic matter mineralization, and their inherent ability to biomineralize, make them extremely important agents in the Ba biogeochemical cycle. Thus, reconstruction and interpretations of past productivity and its potential spatial variations as well as fluctuations over time need to consider this microbial paleoperspective. In fact, in the modern Mediterranean, some significant differences in types of productivity and bacterial production exist, which could have also been important in the past, resulting in regional changes in barite production. Assessing the nature of barite-related processes is therefore crucial for the correct interpretations of primary productivity variations during sapropel deposition. In fact, the strong link between organo-mineralization and microbial processes in the past still requires further investigation to determine factors controlling barite accumulation rates in the Mediterranean sapropels.