bluuebunny/crossref_metadata_2025 huggingface dataset:
Long-term observations of halogen oxides in the Arctic: project overview and first results
Authors: Lauster Bianca , Donner Sebastian , Frieß Udo , Platt Ulrich , Reischmann Lucas , Simpson William , Ziegler Steffen , Wagner Thomas
Published: March 2024

Halogen chemistry is a central element of tropospheric ozone depletion events (ODEs) during polar spring. However, key processes such as source mechanisms of reactive halogen species, their transport, and interhalogen interactions are still not fully understood. Further, a quickly changing Arctic climate is expected to have a strong impact on halogen activation and ODEs, but more research is needed to make meaningful predictions about these changes.We deployed a Long-Path Differential Optical Absorption Spectroscopy (LP-DOAS) instrument in Utqiagvik (formerly Barrow), Alaska, in December 2023. The instrument was originally purpose-built for its previous deployment at the German research station Neumayer, Antarctica, where it operated successfully for more than two years (Nasse, 2019). In the Arctic, seasonal atmospheric transport and the township’s proximity to the observation site will lead to a larger anthropogenic influence by air pollution. Also, the different climatic conditions are likely to lead to further insights into the complex interactions between halogens and other trace gases, such as NO2.To improve the data quality, the instrumental set-up was extensively tested and optimised accordingly using the knowledge gained from the previous campaign in Antarctica. An overview of the instrument characteristics as well as the project outline will be presented. Moreover, first results of the LP-DOAS data will be shown focusing on data quality and data analysis.
Paleomagnetism and calcite U-Pb geochronology from the Penglaitan GSSP section, South China
Authors: Zhang Min , Qin Huafeng , Deng Chenglong , Shen Shu-zhong , Pan Yongxin
Published: March 2024

The Guadalupian-Lopingian boundary (GLB) interval is characterized by the Pangea breakup, dramatic sea-level change, Emeishan Basalt volcanism, and biotic turnover. We conducted magnetostratigraphic, mineralogical, and calcite U-Pb geochronological studies at the Penglaitan Global Stratotype Section and Point section in South China. Rock-magnetic results indicate that magnetite and rare hematite are the dominant remanence carriers. After removing the viscous remanent magnetization, three components were isolated from the limestone at the Penglaitan section. The high-temperature remanence components were isolated from the tuffaceous limestone and yielded a mean direction of Ds/Is = 195.3°/+5.6° (α95s = 5.3°, ks = 22.8, n = 34) after tilt correction. It defined a reversed magnetozone from the top of conodont Jinogondolella granti Zone to the lower part of the Clarkina. dukouensis Zone, straddling the GLB. Additionally, intermediate-temperature components represent the Jurassic and Triassic remagnetization, also supported by the in-situ calcite U-Pb dating (~133-166 Ma and ~213-224 Ma), pyrite-to-magnetite alteration, or magnetite oxidization to maghemite and hematite. The new paleomagnetic results and calcite U-Pb dating provide new insights into Mesozoic multi-remagnetization in the South China Block and refine the GLB positioned in a reversed magnetozone.
Prediction of runoff-generated debris flows using hydrological modeling
Authors: Bernard Martino , Barbini Matteo , Berti Matteo , Boreggio Mauro , Schiavo Massimiliano , Simoni Alessandro , Vesco Lopez Sandivel , Gregoretti Carlo
Published: March 2024

In the Dolomites area, steep rocky cliffs are incised by several chutes that concentrate runoff and deliver it to the scree at their base. This interaction prompts erosive actions, creating channels for debris flows. After intense, short-lasting rainfall, the resulting runoff carries a significant amount of loose debris, forming a solid-liquid surge. This surging flow entrains boulders, gravel, and sand along its path, transforming into an increasingly substantial stony debris flow. To explore how headwater rocky catchments respond hydrologically and trigger stony debris flows, we utilize data gathered from three monitoring stations placed in distinct debris-flow catchments. These stations, located in the debris-flow initiation area of the basins, capture videos and flow-stage data, enabling us to observe the timing and type of the incoming flows. Over 15 years of monitoring, numerous instances of runoff and mass-transport phenomena have been documented. This comprehensive dataset is precious for analyzing the hydrological behavior of small, steep headwater basins and investigating stony debris flow initiation. An existing hydrological model has been partially reformulated, and its updated version was calibrated using the hydrographs measured via a sharp-crested weir. Testing this updated model against observations from two larger debris-flow catchments affirms its capability to replicate the initial phases of a debris flow, particularly when the sediment concentration is quickly increasing. Moreover, combining simulated runoff volume with the entrained sediment volume in the Rovina di Cancia catchment, estimated through DEM of Differences for the debris-flow events that occurred from 2009 to 2022, provides values for solid concentration suitable for predicting sediment volumes carried by debris flows.
Driving energy systems with synthetic electricity prices
Authors: Efstratiadis Andreas , Sakki Georgia-Konstantina
Published: March 2024

The electricity market across Europe, which is key driver of energy systems, has been subject to structural changes in the last years, in order to favor the penetration of renewables and foster decarbonization. A substantial guiding principle was the establishment of the Target Model, configurating a new era of the energy as a trading product. The corollary of this is that the market price became more dependent on socioeconomic disturbances and highly unpredictable events, such as financial, geopolitical and health crises. As a consequence, the variability of electricity prices has been substantially increased across all scales (intra-day, seasonal and long-run). In order to embed this major facet of uncertainty within energy systems modelling, we introduce a generic stochastic simulation framework to represent the market dynamics as a random process across scales. Key challenge is capturing the behavior of electricity prices that are characterized by significant peculiarities, such as volatility and spikes, as well as double periodicity, across seasons and within the intraday cycle. Further challenges are induced by the limited statistical information under the Target Model structure, and the need to implement within the synthetic data abnormal yet persistent shifts, as observed during the recent energy crisis. To stress-test our methodology, we simulate the quite different statistical response of the electricity prices in Greece and Portugal – two countries with similar economic conditions, fiscal compliance, and financial sector development.
The apparent density distribution of the lunar crust revealed by the spherical coordinate-based mapping method
Authors: Yang Jing , Guo Lianghui
Published: March 2024

As an important physical property of the Moon, the lunar crustal density provides evidence for the early evolution process of the Moon, such as the asymmetry of its nearside and farside. The apparent density is the average value of the bulk density at a certain depth. The gravity inversion method is an effective tool of determining the apparent density distribution of the lunar crust. Benefiting from the lunar GRAIL mission's high-precision gravity field models, it is theoretically possible to establish a global high-resolution apparent density model through the gravity inversion. However, there are two major problems, namely, the accuracy and efficiency of the inversion. To solve these problems, different from the admittance methods, we develop a high-precision apparent density mapping method in the spherical coordinate. The improved 2D Gauss-Legende formula and adaptive subdivision algorithm are adopted to calculate the high-precision gravity anomalies of the Tesseroid cells. The parallel algorithm based on OpenMP is involved to improve the calculation efficiency of the global data. And the Cordell iterative algorithm is utilized to derive the apparent density model fitting the real gravity anomalies. The synthetic data tests verify the accuracy and efficiency of our method. Subsequently, we use LOLA topographic data to correct the gravity anomalies obtained from GRAIL and derive the global lunar Bouguer gravity anomalies. The lunar crust thickness model given by Wieczorek et al (2013) is chosen as the bottom interface of the density layer. As a result, we obtain a global high-resolution lunar crust apparent density model with a resolution of about 20 km by the presented mapping method. Our model shows that the apparent density of the lunar crust ranges from about 2200 - 2900 kg/m3 with a mean value of about 2600 kg/m3. The Procellarum KREEP Terrane (PKT) and the large impact basins present higher apparent density, while the Feldspathic Highlands Terrane (FHT) varies around the mean apparent density, and there is a significant variation within the South Pole-Aiken Basin Terrane (SPAT). Our apparent density distribution around the PKT and FHT is significantly relevant to the surface grain density model derived from the current FeO and TiO2 abundance map. However, our apparent density distribution around the SPAT differs from the surface grain density, suggesting a more complex density structure in this region.
An efficient use of a Lagrangian transport model for atmospheric inversions using satellite observations: case study using TROPOMI to estimate CH4 emissions over Siberia
Authors: Krishnankutty Nalini , Thompson Rona L. , Pisso Ignacio , Schneider Philipp , Stebel Kerstin , Sasakawa Motoki , Platt Stephen M.
Published: March 2024

We present a novel and efficient method for atmospheric inversions of satellite observations using a Lagrangian Particle Dispersion Model (LPDM) and demonstrate its use for a case study in Siberia. LPDMs have several advantages over Eulerian models. First, they can more precisely represent an observation since calculations are independent of a computational grid and second, LPDMs can be run in a backwards in time mode, which allows the computation of the sensitivity of an observation to fluxes and in this way are sometimes said to be “self adjoint”. The LPDM used in our study is FLEXPART.In our method, FLEXPART is run in a backwards-in-time mode to determine total column source-receptor relationships (SRRs), which describe the relationship between a total column observation (such as from a satellite) and fluxes. The SRRs are used in the Bayesian inversion framework, FLEXINVERT, to optimize fluxes over a nested domain. Background mixing ratios for the total column observations are determined by coupling FLEXPART backward trajectories with the outputs of an optimized global Eulerian model (TM5).We demonstrate the method in a case study, determining CH4 emissions over Siberia using observations from the TROPOspheric Monitoring Instrument (TROPOMI) onboard Sentinel 5P. Siberia was chosen as it is a region with important emissions from oil/gas facilities and coal mining, as well as abundant natural sources from wetlands. The posterior fluxes obtained using TROPOMI XCH4 are evaluated by comparing to inversions using observations from the ground-based network, JR-STATION.
Fisrt edition of an “Ocean Readings Prize, a better knowledge for a better preservation”.
Authors: Spilmont Helene , Van Ommeslaeghe Sophie , Jarnier Nathalie , Masset Katy , Klawinski Aline
Published: March 2024

Like the Goncourt for high school students, the aim is to have a book prize awarded by pupils on the theme of the environment and more particularly the Ocean.The objectives of this project are: - Get pupils to read / awaken the pleasure of reading in pupils - Provide knowledge on ocean ecosystems, in partnership with Nausicaa, the largest aquarium in Europe located in Boulogne Sur Mer.- Create a link between collège and lycée (key stage 4 and 5 pupils)- Develop oral skills by arguing choices (when choosing the winner of the prize) and presenting their final work in Nausicaa.The books (one manga, one novel, one graphic novel, one graphic documentary and one comic) were selected last June by the instigators of the project. Set up :A call for proposals was launched in June 2023 to secondary schools (collèges and lycées, key stage 4 and 5 pupils) in Boulogne sur Mer and the surrounding area. Thirteen colleagues from five different schools responded favorably (in total the project gathers 190 pupils).Pupils from these schools work on these readings all along the school year. Various activities are carried out with their librarian teachers, science and French teachers.Examples of activities carried out at the Branly high school are: cards game to discover the books, reading sheets, “speed reading”, and the production of a “bestiary” around the animals found in the books as final task.At the same time, all these classes regularly visit Nausicaa during the school year, which is an occasion to supplement the knowledge provided by the readings, and to enrich the final works.A collège-lycée meeting is planned for next April. On this occasion, pupils will present their final work and discuss about the readings to elect the winner of the prize.The high point of the project will be on World Oceans Day (7th of june) in Nausicaa.The winning author of the prize will be invited, as well as all the students who participated in the project. This day will be an opportunity to highlight work carried out during the year and to meet the prize-winning author. 
Real-time flood and water level forecasting using AI-based models for early warning and disaster risk reduction
Authors: Bagli Stefano , Mazzoli Paolo , van der Brink Koen , luzzi valerio , papa mario
Published: March 2024

The increasing frequency and intensity of floods pose a significant threat to lives, property, and infrastructure. Real-time flood forecasting is crucial for early warning systems and disaster risk reduction. However, traditional forecasting methods often have limitations in terms of accuracy and timeliness.This paper, developed under the framework of AI4Copernicus 5th Calls project, presents a data-driven approach for real-time flood and water level forecasting using AI and machine learning algorithms. The proposed system is based on a hybrid model that combines multiple machine learning algorithms, including DLinear/NLinear, LSTM Hindsight Modelling, and FLEX. The system is trained on historical data on hydrological and meteorological features, and is able to predict water levels at river gauging stations up to the next 9 hours.The system has been tested on data from the Lamone River in Italy, and has been shown to achieve a mean-absolute-error of only a few (
Studying the Presence and Distribution of Microplastics in a Norfolk Salt Marsh
Authors: Grover Benjamin , Nolte Stefanie
Published: March 2024

As a rising global pollution issue, microplastics have been discovered in every major environment around the world. Marine and coastal ecosystems in particular are often highlighted for the presence and impacts of plastic pollution; however, salt marshes are quickly gaining interest, and concern, as potential traps and long-term sinks for microplastics.Fundamental sedimentation processes within salt marshes are hypothesised to be ideal for microplastic accumulation, as well as potential abundant physical trapping from vegetation. Salt marshes also provide ideal natural conditions that promote the breakdown and degradation of plastic, thus leading to several different incoming sources of microplastic. With several possible plastic inputs, there is the potential for high microplastic concentration in salt marshes, however when compared to other coastal ecosystems, there are very few studies within this habitat and so plastic levels are largely unknown.As habitats with important ecosystem services such as biodiversity and carbon storage, it is critical that we improve our understanding of the impacts which microplastics may have upon salt marshes. However, to do this we must first understand what the spread of microplastics in this environment is. This project hopes to measure the amount of microplastics in a natural salt marsh, focussing on their spatial distribution throughout the marsh and neighbouring mudflats. From this initial location data, we will then investigate the impact of physical marsh attributes on any distribution trends and see how much the amount of microplastics across the marsh can be explained by these factors.
 Using Quantitative Diagenesis to characterise and understand carbonate CCUS prospects
Authors: Mohammed-Sajed Omar , Rashid Fraidoon , Glover Paul , Collier Richard , Lorinczi Piroska
Published: March 2024

Recent years have seen the growth of new techniques that combine conventional stratigraphic and observational approaches to characterizing the type, scope, extent, timing and effects of diagenetic processes with petrophysical measurements of their rock microstructure. These Quantitative Diagenetic (QD) techniques can be used to predict post- and pre-dolomitisation porosities and permeabilities as well as trace the pathway of the diagenetically evolving rock through different stages of diagenesis that may turn a low-quality carbonate reservoir into a high-quality reservoir, or vice versa. While these new QD techniques are becoming useful for the characterization of hydrocarbon reservoirs, they are also extremely useful in the characterization of carbonate reservoirs for prospective CCUS use. This paper will briefly explain some of the main approaches to QD including dolomitisation prediction, petrodiagenetic pathways, reservoir quality fields, and Fracture Effect Index (FEI), before examining how they can be used to ensure that the prospective CCUS target reservoir is sufficiently well characterized that effective reservoir modelling can take place, and that the volume, flow and trapping of CO2 in the reservoir can be effectively monitored. Dolomitisation is known to be affected by the presence of CO2, with CO2 dissolving in aqueous pore fluids to form carbonic acid that directly affects porosity through dissolution and indirectly by affecting the dynamics of the dolomitisation process itself. There are two current QD methods for predicting the change in porosity upon dolomitisation. One is affected by both the direct and indirect effects, while the other is only sensitive to the indirect effects. Both the direct and the indirect effects can be plotted on a petrodiagenetic pathway. The presence of fractures is also a key aspect of how injected CO2 will flow in a CCUS reservoir. The QD parameter FEI describes the change in permeability of a rock concomitant upon a unit change in fracture porosity (i.e., what increase in flow results from a given increase on fracture porosity). This varies depending upon the degree to which fractures are connected and can be extremely useful in predicting the flow of CO2 within a fractured legacy carbonate CCUS prospect. In summary, QD approaches have the potential to provide those who need to characterise and model carbonate CCUS prospects with new and useful tools. 
A Quantitative Analysis of the Contributions of High-Low Satellite-to-Satellite Tracking (SST) Observations used for Gravity Field Estimation
Authors: Saadat Niusha , Bettadpur Srinivas , McCullough Christopher , Nagel Peter
Published: March 2024

Satellite gravimetry missions continue to provide data to produce high resolution gravity models of the Earth for over 20 years. The Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) exemplifies the current state-of-the-art mission architecture. GRACE-FO consists of a pair of twin satellites flying in the same orbit with an onboard laser ranging interferometer (LRI) system and GNSS receivers. The LRI is used for accurately tracking low-low satellite range change. The GNSS receivers are used for high-low SST to GNSS satellites, contributing information for satellite positioning, timing, and long-wavelength gravity field information.We present results from a numerical simulation study to characterize the contributions of various high low SST observation architectures relative to the GRACE-FO configuration. These include gravity fields estimated with only high-low SST observations as well as fields with combined high-low and low-low SST observations. Other aspects of the setup such as measurement observables, bias parameterization, and noise characteristics are evaluated to better understand how high-low SST and its errors impact gravity field estimation. We anticipate the results to be useful in the architecture and science data analysis algorithms for future mass change missions.
Internal variability, multiple equilibria, and convection-SST coupling in a cloud-resolving model with an interactive ocean
Authors: Sokol Adam , Munteanu Vlad , Hartmann Dennis
Published: March 2024

Future changes in tropical convection will be closely tied to changes in the underlying sea surface temperature (SST) pattern. To understand the convective response to warming in a coupled atmosphere-ocean system, we perform a series of idealized, 20-year radiative-convective equilibrium experiments with a 2D cloud-resolving model coupled to a 25-m slab ocean. The domain length is that of the tropical Pacific basin, and different climates are achieved by varying the parameterized ocean heat transport (q-flux). The simulations are characterized by two distinct regimes of  convection-SST coupling: an oscillatory regime that occurs when the mean SST is near that of the present-day tropical Pacific (27-30 °C), and a non-oscillatory regime at warmer temperatures (>36 °C).The oscillatory regime is defined by internal, 3°C oscillations in mean SST driven by variations in low cloudiness. During the warming phase of the cycle, SSTs are homogeneous, deep convection occurs in two regions, and low clouds are sparse. During the cooling phase, there are well-defined warm and cold pools, deep convection aggregates into a single region, and expansive low cloud decks act to decrease the mean SST.  In the warmer, non-oscillating regime, distinct warm and cold pools still form, but convection is no longer limited to the warmest SSTs. Rather, convection develops over cooler SSTs and is then advected to the warm pool by the mean flow. The expansion of deep convection to cooler SSTs impedes low cloud formation over the cold pool and inhibits the low cloud-driven oscillations in mean SST. Changes in sub-cloud buoyancy explain the expansion of the convectively unstable region.Both regimes (oscillatory and non-oscillatory) can be achieved for the same q-flux depending on initial conditions. Intermediate SSTs (30-36 °C) are unstable on long timescales and eventually revert to one regime or the other. While certain aspects of this behavior are likely sensitive to simulation design, our broader set of experiments suggests potential shifts in convection-SST coupling as the climate warms.
Periodic narrowband radio wave emissions and inward plasma transport at Saturnian
Authors: Ma Xuanye , Wing Simon , Brandt Pontus , Johnson Jay , Mitchell Donald , Kurth William , Menietti John , Delamere Peter
Published: March 2024

The abrupt brightening of an Energetic Neutral Atom (ENA) blob or cloud has been interpreted as plasma injection in the Saturnian magnetosphere (termed ENA injection herein). Morphologically, there appears to be two types of abrupt ENA cloud brightening: (1) the brightening of a large cloud usually seen at distances > 10-12 Rs (Rs = 60,268 km) in the midnight or postmidnight region; (2) the brightening of a smaller cloud usually seen at distances < 10-12 Rs around 21-03 magnetic local time (MLT). Among many radio waves observed at Saturn, type 2 ENA injections correlate best with the 5 kHz narrowband waves. Using Cassini INCA and RPWS data, we examine the periodicities of the type 2 ENA injections and the 5 kHz narrowband emissions as well as their cross-correlations, which have been previously used to measure the lag times or phase differences. Because correlational analysis can only establish linear relationships, we also use mutual information to establish linear and nonlinear relationships. On average, the peak of the 5 kHz narrowband emission lags those of the type 2 ENA injection by about a few minutes to 2 hr. The injection of hot plasma into the inner magnetosphere can lead to temperature anisotropy, which can generate electrostatic upper hybrid waves, which upon encountering the high density gradient at the outer edge of the Enceladus density torus, can mode convert to the Z mode and then to O mode. The 5 kHz narrowband waves commonly propagate in the O mode.
Simple conceptual overview how peculiarities of food production and food supply chain affect land degradation.
Authors: Frouzova Jaroslava , Frouz Jan
Published: March 2024

Simple conceptual overview how peculiarities of food production and food supply chain affect land degradation.Most of the land suitable for agriculture is located in the temperate zone, while the yields of comparable crops in tropical countries (countries of the global south) are almost half compared to developed countries in the temperate zone. In addition to greater soil fertility, the more advanced technological base of economically developed countries. Developed counties the increase their production mainly through its intensification, i.e. greater production on the same area and greater meat, milk or egg production per one livestock specimen. This leads to the concentration of production in suitable conditions, the homogenization of the landscape, reduction of grazing and other extensive form of land use and other negative effects of agricultural intensification on ecosystems. On the other hand, in the countries of the global south, agricultural production is increasing mainly through increasing the production areas, which results in endangering the remnants of the original ecosystems. Number of farmers is decreasing yet they feed larger amount of food consumers. This increasing the efficiency of human work is connected with the transfer of part of the work to the work of animals and later machines which allow one farmer to cultivate larger area of land, and further to the intensification of agricultural production, the use of fertilizers, pesticides, and other substances, so-called additional energy is needed to obtain them. As the intensity of agriculture and the ability of one farmer to feed more people increases, the total amount of energy required to achieve production also increases, not only because total output increases, but also because the amount of additional energy required per unit of output increases. As the amount of additional energy increase recycling of biomass (and energy) inside agriculture system decrease. Along with this, the negative impacts of agricultural production on ecosystems are increasing. These negative impacts are usually greater in the less fertile soils of the global south than in the more fertile soils of developed countries.  Pressure of consumers increase not only due to population increase, but also due to detachment of people from food production, which cause that consumers perceive food mainly by its cost. Food supply chain become driven by retailers, which increase pressure on price, and thus pressure on farmers to optimize production cost often on expense of more intensive soil and land use which may lead to land degradation. Many retailers now use environmental standards which are well suited to control for extensification (such as zero deforestation) but tackling of agriculture intensification is rare.
Low-frequency shadow (LFS) as a tool for CO2 sequestration of Sleipner field North Sea
Authors: Anthony Emmanuel , Bohlen Thomas
Published: March 2024

Seismic low-frequency shadow (LFS) is a zone in the seismic data that is characterized by strong anomalously low-frequency energy compared to its surroundings and it occurs beneath a body that strongly attenuates the energy of the propagating seismic waves. LFS can be used as a tool to monitor the migration of CO2 in a reservoir. To demonstrate this on the Sleipner field, North Sea, where a large amount of CO2 is being sequestered in the deep saline Utsira Formation. A spectral decomposition analysis of time-lapse 3D seismic data of the Sleipner field, North Sea, was carried out using the continuous wavelet transform. We examined the common frequency stacks corresponding to frequencies 10 Hz, 14 Hz, 30 Hz, and 40 Hz for the occurrence of LFS in the pre-and post-CO2 injection cases data. We did not find any signatures corresponding to LFS in the pre-CO2 injectionscenario. In the post-CO2 injection cases, LFSs were detected below the reservoir base at frequencies lower than 30 Hz. It is shown that the seismic low-frequency shadows are not artefacts but occur due to attenuation of the high-frequency components of the propagating seismic waves in the CO2-saturated Utsira Formation. The low-frequency shadows are localized anomalies at the base of the formation; hence it can be applied to study the behaviour of CO2 when stored in a reservoir.
Co-occurrence of boreal smoke plumes and enhanced surface ozone across the central USA during summer 2023
Authors: Cooper Owen , Chang Kai-Lan , McDonald Brian
Published: March 2024

From May 20 through July 25, 2023, large boreal forest fire plumes were transported across the central and eastern United States of America. On many days the U.S. Environmental Protection Agency (EPA) air quality monitoring network detected co-located ozone and PM2.5 anomalies, which indicate a contribution from the smoke to surface ozone production. We apply a general additive mixed model (GAMM) to interpolate the observed ozone and PM2.5 observations onto daily maps of the continental United States.  Comparison to a recent baseline period with below-average wildfire activity (2014, 2016, 2019) allows for the identification of smoke events that contributed to enhanced surface ozone levels.
Effect of waves on the magnitude and direction of wind stress over the ocean
Authors: Villarreal-Olavarrieta Carlos E. , Ocampo-Torres Francisco J. , Osuna Pedro , Mora-Escalante Rodney E.
Published: March 2024

Wind Stress plays a vital role in the sea-atmosphere interaction process, which affects climate, weather, and oceanic circulation models. Wind drag coefficient parameterizations are usually used to estimate wind stress; these relationships tend to overestimate or underestimate the momentum transfer, especially in weak to moderate wind regimes during swell conditions. Also, it is commonly presumed that the wind stress is always aligned with the wind, but this is only sometimes the case.The wind stress and its turbulent and wave-coherent components were estimated through measurements of the free surface level and the wind speed using a spar buoy with a sonic anemometer and an array of six wave staffs. The state of the sea was also characterized by obtaining the directional spectrum of the waves. Continuous measurements were made for at least four months at three different sites (two in the Gulf of Mexico and one in the northern Mexican Pacific) with sampling rates of 10 Hz for free surface level and 100 Hz for wind speed. Multiple swell systems’ influence on the wave boundary layer is avoided by only analyzing events with a single dominant wave system. It was observed that during swell conditions with wind traveling in the same direction, the wave-coherent wind stress component has an opposite direction to the wind, which dampens the total wind stress magnitude. During counter-directional wind relative to swell traveling direction, the wave boundary layer is modified; it appears that swell accelerates wind near the surface without changing its direction, resulting in a wind stress magnitude more significant than expected.Also, during the wind stress analysis, a reference frame oriented to the propagation direction of the primary wave system was found to be better for asses wind waves’ influence on the wind stress magnitude and direction. Using this frame of reference makes it possible to isolate wind wave influence on wind stress in its directional component aligned with the wave direction. The perpendicular directional component relative to the wave’s direction is primarily turbulent.
Indian Ocean Dipole Intensifies Benguela Niño Through Congo River Discharge
Authors: McPhaden Michael , Jarugula Sreelekha , Aroucha Leo , Luebbecke Joke
Published: March 2024

Benguela Niños are periodic episodes of unusual El Niño-like warming in the upwelling zone off the coast of southwest Africa with significant impacts on marine ecosystems, coastal fisheries and regional weather variability.  The strongest Benguela Niño in the past 40 years occurred in February-April 1995 with areal average sea surface temperature (SST) anomalies of 2°C and local anomalies up to 4°C off the coast of Angola and Namibia.  Benguela Niños are generated through a combination of remote and regional wind-forced dynamical processes originating within the Atlantic basin. However, a recent study has argued that the extraordinary warming observed in early 1995 resulted from southward advection of unusually high fresh water discharge from the Congo River, which led to the formation of thin mixed layers that trapped heat near the surface to boost coastal SSTs. The purpose of this presentation is to show that a strong Indian Ocean Dipole (IOD) that peaked in September-November 1994 was the reason for the high Congo River discharge in early 1995. IOD events are roughly the Indian Ocean equivalent of El Niño and La Niña events in the Pacific, which are generated though anomalous coupled interactions between surface winds and SSTs. It has been previously demonstrated that the IOD can affect eastern tropical Atlantic sea surface salinity through Congo River basin hydrology.  In particular, positive IOD events (warm SSTs in the western Indian Ocean and cold SSTs in the east) like that which occurred in 1994 lead to elevated Congo River discharge and subsequently lower eastern tropical Atlantic sea surface salinity.  However, it has not been previously shown how these the end-to-end processes originating with IOD development can affect Benguela Niños.We use a variety of data sets and reanalyses (both oceanic and atmospheric) to show how during the 1994 IOD event, moisture was transported through the atmosphere from the western Indian Ocean to the Congo River basin where it converged and rained out to increase Congo River discharge.  The freshwater discharge in turn was advected southward in early 1995 which resulted in formation of thin surface mixed layers atop thick barrier layers that arrested the entrainment of cold subsurface waters, thereby amplifying Benguela Nino SSTs. We further show that this sequence of events has occurred at other times, as for example during a weak 2015 IOD and subsequent 2016 Benguela Niño.  These results suggest that the significant temporal lags between IOD development, Congo River basin rainfall, river discharge, and offshore accumulation of freshwater offer opportunities for improved seasonal forecasting of Indian Ocean impacts on the Atlantic through ocean-atmosphere-land interactions.
Remote Sensing of Column CO2, Atmospheric Pressure, and Vertical Distribution of Dust and Clouds on Mars using Differential Absorption Lidar at 1.96 µm on an Orbiter
Authors: Liu Zhaoyan , Campell Joel , Lin Bing , Yu Jirong , Geng Jihong , Jiang Shibin
Published: March 2024

By utilizing progress in millijoule-level pulsed fiber lasers operating in the 1.96 µm spectral range, we propose a novel concept introducing a differential absorption barometric lidar designed for remote sensing of Martian atmospheric properties on an orbiter. Our emphasis is on the online wavelength situated in the trough region of two absorption lines, chosen for its insensitivity to laser frequency variations, thereby mitigating the need for stringent laser frequency stability. Our investigation centers around a compact lidar configuration, featuring reduced telescope dimensions and lower laser pulse energies. These adjustments are aimed at minimizing costs for potential forthcoming Mars missions.The primary measurement objectives include determining column CO2 absorption optical depth, columnar CO2 abundance, surface atmospheric pressure, as well as vertical distributions of dust and cloud layers. By combining surface pressure data with atmospheric temperature insights obtained from sounders and utilizing the barometric formula, the prospect of deducing atmospheric pressure profiles becomes feasible. Simulation studies validate the viability of our approach. Notably, the precision of Martian surface pressure measurements is projected to better than 1 Pa when the aerial dust optical depth is anticipated to be under 0.7, a typical airborne dust scenario on Mars, considering a horizontal averaging span of 10 km.
Predicting observed induced seismicity due to production in the Hverahlid, SW Iceland, geothermal field
Authors: Hjörleifsdóttir Vala , Jónsdóttir Kristín , Geirsson Halldór , Benediktsdóttir Ásdís , Kristjánsdóttir Sigríður
Published: March 2024

The Hverahlíð geothermal field, located in the fissure swarm of Hengill volcano, SW Iceland, has been producing steam and geothermal fluids for the Hellisheiði geothermal power plant (303 MWe, 210 MWth), since late 2016.  A total of 7 geothermal wells in the field (HE-21, -26, -53, -54, -60, -61 and -66) have been producing up to 150 kg/s of steam and 60-70 kg/s of separated liquid.  The combined extraction from the wells is limited by the size of the steam pipeline connecting the field to the power plant.  Within months of the initiation of production an increase in seismicity was noted within the field.  This is in contrast to the nearby Hellisheiði geothermal field, ~2 km away, which has experienced very little induced seismicity since commission in 2006, despite more than twice as high mass extraction rates and higher deformation rates.  Since early 2018 a total of 8 events with M> 2.5 have occurred in the field.  The latest of these events occurred in November 2022 with M 3.2. The seismicity largely does not line up on faults and is relatively evenly distributed throughout what is considered the top of the geothermal reservoir (Kristjánsdóttir et al 2019).Currently a second pipeline connecting the geothermal field with the power plant is in construction and with the commission, planned for fall 2024, an increase in mass extraction rates from the Hverahlíð geothermal field  of ~30% is expected.In this presentation we compare the observed location, seismicity rates and Mmax values to those expected from different models of earthquake triggering.  We furthermore predict the expected increase in seismicity rates due to the increase in production rates and the increase in seismicity that will be felt by the neighboring community of Hveragerði.
Towards improvement to understand plastic dynamics in global rivers
Authors: Nakayama Tadanobu
Published: March 2024

Plastic pollution has been receiving considerable attention from scientists, policy makers and the public during the last few decades. Though some models succeeded to simulate transport and fate of plastic debris in freshwater systems (Meijer et al., 2021), a complete model is under development to elucidate the whole picture of plastic dynamics in continental scale. Previously, process-based eco-hydrology models, NICE (National Integrated Catchment-based Eco-hydrology)-BGC (BioGeochemical Cycle) (Nakayama, 2017), was applied to evaluate biogeochemical cycling in river basins ranging from local/regional to continental/global scales. Recently, the author linked NICE-BGC to plastic debris model that accounts for transport and fate of plastic debris (advection, dispersion, diffusion, settling, dissolution and biochemical degradation by light and temperature), and applied this new model to regional scale (Nakayama and Osako, 2023a) and global major rivers (Nakayama and Osako, 2023b). NICE-BGC was also improved to include the mass budget in water and bed sediment in order to show the seasonal variations of plastic fluxes. In this study, NICE-BGC was further extended to incorporate biofouling (with algae and phytoplankton) and heteroaggregation (with suspended particulate matter) to improve the accuracy of global plastic dynamics in global river basins and the amount of plastic flows from land into rivers and finally into the ocean. Model simulated size distribution of plastics in water and riverbed sediment of global major rivers and showed the difference of effect of biofouling and heteroaggregation in each river. In addition, the simulated result showed that flood events have a great impact on plastic mobilization and its high intra-annual variability mainly caused by settling, resuspension, and bedload transport (Hurley et al., 2018; van Emmerik et al., 2019). These results aid development of solutions and measures to reduce plastic input to the ocean, and help to quantify magnitude of plastic transport under climate change. ReferencesHurley, E., et al. 2018. Nature Geoscience, 11, 251-257, doi:10.1038/s41561-018-0080-1.Nakayama, T. 2017. Journal of Geophysical Research: Biogeosciences, 122, 966-988, doi:10.1002/2016JG003743.Nakayama, T., Osako, M. 2023a. Ecological Modelling, 476, 110243, doi:10.1016/j.ecolmodel.2022.110243.Nakayama, T., Osako, M. 2023b. Global and Planetary Change, 221, 104037, doi:10.1016/j.gloplacha.2023.104037.van Emmerik, T., et al. 2019. Scientific Reports, 9, 13549, doi:10.1038/s41598-019-50096-1.
years results of EQ precursors research by using CSES-01 onboard and the following step of  IMCP 
Authors: Shen Xuhui , zhang xuemin , Zeren zhima , Zhao Shufan , Liu Qinqin , Battiston Roberto , De Santis Angelo , Liu Tiger , Tramutoli Valerio , Conti Livio , Yan Rui
Published: March 2024

As the first geophysical field observation satellite mission in China, CSES-01 has been operating in orbit for six years and, based on its optimal performance, it will prolong its life after CSES-02's launch in orbit in order to partly overlap the two missions. In retrospect, CSES-01 acquired an amount of data such as geomagnetic field, low-frequency electromagnetic waves, in-situ plasma content, and temperature, charged particles as well ionospheric plasma, while more than 70 M7+  and 700 M6+  earthquakes  have been recorded in the globe, together with a series of space weather and volcano phenomena. The large amount of data collected has provided new ground for in depth exploration on statistical analysis of earthquake precursors as well as providing clear evidence for the feasibility of space-based co-seismic observation, helping the development of quantitative modeling of the Lithosphere-Atmosphere-Ionosphere Coupling mechanism focusing on its atmospheric and electromagnetic wave channel.The following prospect plan, CSES-02, is under development by China-Italy joint team and is due to launch in 2024, which means that we will have two CSES satellites simultaneously in orbit from 2024. Such an increase in observational capabilities will strongly support the implementation of multi-parametric observation systems, both from the ground and from satellites, capable of significantly improving precision and reliability of earthquake forecasts. In addition, the new International Meridian Circle Project  (IMCP)   will be implemented as a ground-based observation network with its primary objectives of monitoring the geomagnetical field, space weather, and interaction among Lithosphere-Atmosphere-Ionosphere. The main tasks of IMCP are global data sharing, joint research on space weather and natural hazards, global change, and many other science fields. 
Using Inverse GNSS Methods for the Determination of C20 and C30 Gravity Field Coefficients for the Support of GRACE Solutions   
Authors: Nowak Adrian , Zajdel Radosław , Gałdyn Filip , Sośnica Krzysztof
Published: March 2024

The distribution of atmospheric, hydrological, and oceanic mass loads on the lithosphere affects the deformation of the Earth's surface over time. Monitoring of the relative displacements of the dense global network of permanent Global Navigation Satellite System (GNSS) stations enables the direct measurement of these loads on a global scale. The application of inverse GNSS methods provides an independent tool to retrieve the time variable gravity (TVG) models of the Earth system and to support hydrogeodesy studies, including the monitoring of the water storage cycle or polar ice mass loss.The goal of this study is to investigate the effectiveness of using inverse GNSS methods to provide independent C20 and C30 coefficients. These coefficients are essential for deriving highly accurate Gravity Recovery and Climate Experiment (GRACE)-based TVG models. In this study, surface mass variations of low-degree TVG coefficients are derived from the displacements of continuously tracking GNSS sites based on the 21 years (2000-2021) of the Center for Orbit Determination in Europe solutions of the 3rd data reprocessing campaign of the International GNSS Service in the framework of the preparation of the International Terrestrial Reference Frame 2020. The geometrical displacements of the GNSS stations calculated by inverse methods are compared with changes in the gravity field based on independent estimates obtained from the GRACE and GRACE Follow-On (GRACE-FO) satellite missions and the Satellite Laser Ranging (SLR).As an alternative to the solutions provided by SLR, it is shown that the C20 and C30 coefficients can be derived based on GNSS station displacements. The challenge of the inverse GNSS approach is to properly choose the maximum degree of TVG expansion. Compared with the SLR-based solution, the most consistent GNSS estimate of the temporal gravity variation rate of the C20 coefficient (−1.73 ± 0.10 × 10−11/year) and annual variation (4.7 ± 0.6 × 10−11/43.9° ± 7.5°) was obtained by expansion of the spherical harmonics to degree and order of 8. The GNSS-based C30 series is superior to the SLR-based estimates before the launch of the Laser Relativity Satellite. From August 2016, when the C30 estimates are essential for correcting the GRACE solutions, the root mean square between GNSS and SLR solutions is 4.2 × 10−11. GNSS could potentially support GRACE/GRACE-FO solutions that face problems in deriving C20 and C30, which are fundamental to estimates of ice mass changes in the polar regions. Recovery of mass change in the Antarctic ice sheet from April 2002 to December 2020 based on the coefficients replaced by GNSS estimates results in a linear trend of −111 ± 3 Gt/year. In comparison, the trend for the SLR-based replacement from Technical Note 14 shows a trend of −114 ± 2 Gt/year.
 A Multi-year Climate Prediction System Based on CESM2
Authors: Kim Yong-Yub , Lee June-Yi , Timmermann Axel , Chikamoto Yoshimitsu , Lee Sun-Seon , Kwon Eun Young , Park Wonsun , A. Hasan Nahid , Bethke Ingo , Fransner Filippa , Karwat Alexia , R.Subrahmanian Abhinav
Published: March 2024

Here we present a new seasonal-to-multiyear earth system prediction system which is based on the Community Earth System Model version 2 (CESM2) in 1° horizontal resolution. A 20- member ensemble of temperature and salinity anomaly assimilation runs serves as the initial condition for 5-year forecasts. Initialized on January 1st of every year, the CESM2 predictions exhibit only weak climate drift and coupling shocks, allowing us to identify sources of multiyear predictability. To differentiate the effects of external forcing and natural climate variability on longer-term predictability, we analyze anomalies calculated relative to the 50-member ensemble mean of the CESM2 large ensemble. In this presentation we will quantify the extent to which marine biogeochemical variables are constrained by physical conditions. This analysis provides crucial insights into error growth of phytoplankton and the resulting limitations for multiyear predictability.