bluuebunny/crossref_metadata_2025 huggingface dataset:
A first step towards a complete Southern Ocean proxy compilation for the Last Glacial Cycle: glacial-interglacial changes in Sea Surface Temperature
Authors: Thöle Lena , Kohfeld Karen , Chase Zanna , Crosta Xavier , Bijl Peter , McKay Nicholas
Published: March 2024

Previous research has suggested that different processes in the Southern Ocean contributed to the drawdown and release of atmospheric carbon dioxide (CO2) during the last glacial cycle (0–130 ka), yet their dynamics and interplay are not fully understood. To unravel the interactions between different processes and to allow for more comprehensive analyses, we aim to compile all previously published proxy data and convert them into the Linked open Paleo Data (LiPD) format, overall increasing interoperability, reusability and impact.The PAGES C-SIDE working group recently highlighted substantial open-ocean sea-ice extent changes during the mid-glacial period (Marine Isotope Stage 4, ~72 to 60 ka), coinciding with a significant drop in atmospheric CO2. However, sea-ice changes are notably absent during the early glaciation (Marine Isotope Stage 5d, ~115 to 105 ka), suggesting they cannot account for the early CO2 decrease (Chadwick et al., 2022).As an initial step, we present our compilation of sea surface temperature (SST) reconstructions from marine sediment records across the Southern Ocean (Latitude > 30°S) for the last glacial cycle. This compilation assesses SST changes in different zones and basins, evaluates SST gradients, and explores the interplay between SST and sea ice.Our findings reveal a consistent glacial-interglacial amplitude of 5-10°C across all basins and zones, with uniform timing. SST gradients from the Antarctic to Subantarctic Zone remain unchanged over time, eliminating them as a mechanism for early CO2 decrease. Additionally, we observe that 50% of the total MIS 5e-to-LGM cooling in Southern Ocean SST occurred from MIS 5e to MIS 5d, with a second drop from MIS 5a to MIS 4, essentially reaching LGM cooling. A distinct decoupling of SST cooling and sea ice expansion over MIS 5 suggests that circulation and/or subsurface temperatures may exert a stronger influence than SST on sea ice extent. This emphasizes the necessity for additional proxy compilations to further disentangle these complex relationships.
Climate storminess as a driver of surface processes and a limiting factor for topographic responses to rock uplift
Authors: Harries Rebekah , Reaney Sim , Aguilar Germán , Kirstein Linda
Published: March 2024

In the south-central Andes, a long-term persistent pattern in climate aridity has been linked to sediment storage in mountain valleys and the resultant delaying of river steepening in response to rock uplift over millennia. This conceptual model implies that the landscape has a long-term trajectory for sediment export that may be sped up or slowed down by projected climate change. With this framing, we seek to investigate how changes in precipitation patterns and discharge regimes impact the transient evolution of a semi-arid, post glacial landscape and its physical processes. Changes in precipitation patterns and discharge regimes are understood to drive substrate erosion, sediment transport and changes in channel patterns and dimensions. They also alter vegetation, weathering regimes and catchment morphologies that influence sediment supply and slope-channel coupling.  

Using field data, we investigate how a sequence of floods has driven the conveyance of sediment through a semi-arid, postglacial landscape. Along the Rio Teno in Central Chile, we quantify changes in vertical bed structure, bed surface grain size, clast lithology, river morphology and slope-channel connectivity in March 2021 and again following an extreme and a large flood event in 2023. Our findings highlight the importance of including the full range of flood magnitudes that exceed critical entrainment thresholds in models of sediment export and landscape evolution. While extreme events do significant work in redistributing sediment within a catchment, it is the higher frequency, lower magnitude events and snowmelt cycles that evacuate sediment and reset base levels. In the context of climate change, a hydroclimate dominated by extreme floods in this landscape would likely result in greater sediment export from postglacial upper reaches, sediment storage within valleys in mid-reaches and lateral erosion and sediment export along the lowest reaches. This potential change has significant implications for understanding the fate of mountain landscapes and their human populations over the next century. 
The Parliamentary Evening – a successful instrument of the Science-Policy Dialogue
Authors: Lohkamp Meike
Published: March 2024

A popular instrument of the Science-Policy Dialogue in political Berlin is the Parliamentary Evening. A Parliamentary Evening is a closed event for members of state parliaments and the German Bundestag, as well as employees of ministries. The goal is to facilitate information exchange between politics, administration, and science. Parliament members are invited both as speakers and guests. Discussions cover strategic and current issues within the intersection of politics, science, and society, as well as specific topics from various societal domains. The long-term objective of these events is to engage members of parliament and ministry staff in political and public projects, establish connections between parliamentarians and institutions, and enhance the knowledge of the participants. Last year, we organized a Parliamentary Evening on climate-resilient cities. Here, we report on the preparation, implementation, and follow-up of the event, as well as its impact and challenges.
Diagnosing the dynamical and chemical stratospheric tropical width using model and observational data
Authors: Ivaniha Oksana , Abalos Marta , Calvo Natalia , S. Shah Kasturi , Davis Sean , Stiller Gabriele
Published: March 2024

Transport in the stratosphere is characterized by upwelling in the tropics and downwelling in the extratropics, and these regions are separated by the so-called turnaround latitudes. In the winter hemisphere, a region of intense wave breaking (the ‘surf zone’) separates the tropics from the polar vortex. In the summer hemisphere, easterly winds do not allow for penetration of planetary waves into the middle and upper stratosphere.Observational evidence of this global transport circulation comes from the shape of long-lived tracer contours. While the overturning circulation tends to steepen latitudinal gradients of tracers, large-scale stirring by wave breaking leads to quasi-horizontal mixing and thus flattens the gradients. The observed shape of tracer contours results from the combined effects of the two transport processes, and is therefore not trivially related to the turnaround latitudes or mixing diagnostics.In this study we compare several tracer-based and dynamical-based diagnostics of the tropical width computed both from a CESM1-WACCM model simulation and from satellite observations  and reanalysis data. We find notable differences between the dynamical and tracer metrics particularly in the seasonality, with good correspondence only in the equinox seasons. We also examine the interannual variability and long-term trends.
Dansgaard Oeschger event and its dependence on background glacial climate condition simulated in a coupled Atmosphere-Ocean GCM, MIROC
Authors: Abe-Ouchi Ayako , Chan Wing-Le , Sherriff-Tadano Sam , Obase Takashi , Kuniyoshi Yuta , Mitsui Takahito , Buizert Christo
Published: March 2024

Glacial periods were punctuated by abrupt millennial scale climate changes, such as Dansgaard Oeschger events, Boeling-Allerod and Younger Dryas. Although glacial abrupt climate changes were shown to have a strong link to the Atlantic Meridional overturning circulation (AMOC) changes and the glacial background climate, simulating the stability and millennial change of AMOC and climate with fully coupled ocean-atmosphere GCM have been challenging. Here we present many cases of millennial scale climate variability with our Atmospheric Ocean coupled GCM, MIROC4m. A series of long transient experiments (> 10, 000 years) were performed systematically with different steady glacial conditions (CO2 level, obliquity, precession, meltwater, ice sheet size), to study the dependence of the sweet spot of millennial scale variability on the background climate and summarize the results as phase diagrams. We chose the model version which we simulate LGM AMOC weaker and shallower than the AMOC under Pre-Industrial condition. A reasonable sweet-spot of oscillation exists when the Northern Hemisphere ice sheets exist even without freshwater perturbation. In the sweet spot, self-sustained oscillation with bipolar seesaw pattern and shift between interstadial and stadial occur, with interval between abrupt events ranging from 1000 years to more than 5000 years depending on the background condition, while an abrupt shift from stadial to interstadial mode occurs in about 100 years. The sweet spot exists when the CO2 level is between 260ppm and 185ppm, depending largely on the obliquity but marginally on the precession and ice sheet size. When the obliquity or the CO2 amount is large (small), the AMOC is in a strong (weak) stable mode of about 18 (10) Sv (Sverdrup). Many aspects of the sweet spot, i.e., the duration of interstadial is longer systematically when the CO2 or obliquity is larger and the relation between the duration of interglacial and Antarctica air temperature, are very much in agreement with the ice core analysis and the deep-sea sediment.
A Reply to “On Spurious Causality, CO2, and Global Temperature”
Authors: Stips Adolf , Liang San , Macias-Moy Diego
Published: March 2024

Stips et al (2016) demonstrated the existing causal relationship between Green House Gases (GHG) concentrations and Global Mean Surface Temperature (GMTA) based on the Information Flow (IF) methodology. Critics on the application of the Information Flow concept as developed by Liang (2008, 2016) has focused on the underlying assumption of uncorrelated residuals (noise) between the time series. However, this assumption can only make sense for a system with two components, as for a multi-dimensional system unobserved noise may well exist. Fundamentally, there can be no such thing like correlated noise at all. It can seemingly only appear because of some hidden process(es). For investigating this in detail a multivariate information flow analysis has been developed. We will show that in our tests using processes with correlated noises, the preset causalities can be well reproduced. Further, it will be demonstrated that reducing autocorrelation within the time series by pre-whitening, confirms the achieved causality directions. Finally, we question the validity of the proposed alternative measure using forecast error variance decomposition based on vector autoregression by Goulet and Goebel (2021), because in their method causal directions can be simply reversed by reordering.  A physically faithful causal measure should be generally independent of ordering. Coulombe, P. G. and Goebel, M. 2021. On Spurious Causality, CO2, and Global Temperature.  Econometrics, 9(3), 33.Liang, X. S. 2008. Information Flow within Stochastic Dynamical System. Phys. Rev. E 78: 031113.Liang, X. S. 2016. Information Flow and Causality as rigorous Notions ab initio. Physical Review E 94: 05220.Stips, A., D. Macias, C. Coughlan, E. Garcia-Gorriz, and X. S. Liang. 2016. On the Causal Structure between CO2 and Global Temperature. Scientific Reports 6: 21691.
Detection of Melt Ponds on Arctic Sea Ice from Infrared Images using AutoSAM
Authors: Reil Marlena , Spreen Gunnar , Huntemann Marcus , Buth Lena , Wilson Dennis
Published: March 2024

The Arctic is significantly affected by climate change, as evidenced by the constant decline of sea ice since the beginning of satellite observations. One driver of this transformation are melt ponds - pools of water that form as a result of melting sea ice during summer. Due to their darker color, they increase the absorption of incoming sunlight and accelerate ice melt. Accurate determination of melt pond extent and characteristics is considered a main factor in reducing uncertainty in Arctic climate models and sea ice concentration retrievals, but precise large scale observations are not available. Most knowledge to date is based on in-situ measurements, which are restricted to small areas. Satellite retrievals offer Arctic-wide coverage on a regular basis but lack resolution. To validate satellite measurements and allow observation at a moderate scale, helicopter-borne images are used. This ongoing work exploits a new dataset of helicopter-borne thermal infrared (TIR) imagery for melt pond retrieval. The derivation of geophysical parameters requires effective segmentation of different surface classes, which is challenged by temporally and spatially varying surface temperatures. We adapt and fine-tune AutoSAM, a prompt-free Segment Anything (SAM)-based segmentation tool that was introduced by Xinrong Hu et al. for medical imagery (Hu, X., Xu, X., & Shi, Y. (2023). How to Efficiently Adapt Large Segmentation Model (SAM) to Medical Images. arXiv preprint arXiv:2306.13731). Initial results with a limited number of annotated images indicate promising outcomes in the generalization of AutoSAM to cases that are rare in the training set, compared to U-Net and PSP-Net approaches. Beyond the scope of this project, this could serve as an example of how to use SAM as a segmentation tool for the remote sensing domain, which is typically hampered by the lack of labeled training data. Code and first results are provided at https://github.com/marlens123/autoSAM_pond_segmentation.
Seasonal Water Turbidity Dynamics in Arid Central Asia: A Case Study of Lake Balkhash, Kazakhstan, Under Changing Environmental Conditions
Authors: Mishra Kanchan , Fitzsimmons Kathryn E. , Choudhary Bharat
Published: March 2024

Lake Balkhash, one of the largest inland lakes in Central Asia, plays a pivotal role in providing water and ecosystem services to approximately 3 million people. However, like many water bodies in dryland regions worldwide, Lake Balkhash's hydrology has been significantly affected by climate change and land cover and land-use shifts driven by population growth and water-intensive economic activities. To manage these vital water resources effectively, monitoring the health of water bodies is essential for effective water resource management, security, and environmental conservation. Turbidity, a water quality indicator, measures the water clarity and represents a broader environmental change, allowing us to assess the water body's health and the extent of anthropogenic impact on the entire catchment. It is a measure of water clarity and serves as a crucial indicator of water health, as it represents the primary mechanism for transporting pollutants, algae, and suspended particles.The present study investigates the temporal and spatial variability of turbidity in Lake Balkhash. We utilize the normalized difference turbidity index (NDTI) with Landsat satellite data spanning from 1991 to 2022 to map turbidity. We consider various climatic and anthropogenic factors, including precipitation, temperature, wind speed and direction, and water levels in and around the lake.Our findings reveal an overall declining turbidity trend over interannual and seasonal timescales. The results provide a significant negative correlation between turbidity, temperature, and water levels at both temporal scales. However, no straightforward relationship emerges between turbidity and precipitation or wind variables. Specifically, during spring and summer, turbidity exhibits a strong association with temperature and water levels, while in the fall season, water levels are more closely correlated with turbidity. These results underscore the substantial impact of rising temperatures and fluctuations in water levels on the turbidity dynamics of Lake Balkhash. These findings highlight that the warming climate and alterations in lake hydrology pose significant risks to water quality, indicating that monitoring water health alone may not suffice to mitigate the impacts of climate change and human activities.  
Towards a real-time railway monitoring system based on Distributed Acoustic Sensing and a Convolutional Neural Net
Authors: Growe Kevin , Tveit Anna , Dong Hefeng , Wienecke Susann , Landrø Martin , Jacobsen Joacim
Published: March 2024

Distributed Acoustic Sensing (DAS) enables cost-efficient retrieval of wavefield information alongside large linear infrastructure elements, such as pipelines, cables or railways. The massive datasets require automated approaches to detect and classify anomalies which can trigger further investigation through an operator, if necessary. Within this work we exploit one week of DAS data from a fiber-optic cable co-located with a 50 km long railway line south of Trondheim, in the center of Norway. The data were acquired with a temporal sampling of 2 kHz and channel spacing of 4 m, resulting in 12500 channels. Treating the DAS time-space domain matrices like images we can make use of well-established techniques from the field of computer vision. We compute sliding RMS windows of 60 s and 1.5 km with 50 percent overlap and use them as input images for a Convolutional Neural Network. The network classifies events such as trains, cars, unknown events as well as different noise classes and artefacts. In order to thoroughly train the network, we labeled approximately 1000 RMS images per class and further applied a variety of data augmentation techniques to finally obtain about 5000 labeled images per class. Once trained, we can simply apply a forward pass through the network every 30 s for all the 1.5 km overlapping segments to obtain a live-classification of events along the entire railway line. We present our workflow as well as initial results and discuss the potential of DAS for future railway monitoring and the challenges that we encounter. If successful, these methods can open up an opportunity to exploit a large amount of fibers co-located with railway lines enabling automatization of real-time railway monitoring.Acknowledgements:We acknowledge Bane NOR and Alcatel Submarine Networks for conducting the data acquisition for this project. This work is supported by the SFI Centre for Geophysical Forecasting under grant No. 309960.
3D discrete element modeling for the simulation of seismic cycles on a strike-slip fault
Authors: Allemand Adélaïde , Jiao Liqing , Klinger Yann
Published: March 2024

Knowing about the geometry of both (i) ruptured zones during seismic events, and (ii) faults throughout seismic cycles, as well as the evolution of this geometry, is important to understand what is controlling the start and the ending of large earthquakes. In this study, we use 3D Discrete Element Modeling (DEM) in order to simulate a strike-slip fault, formed from an initially homogeneous, intact medium representing brittle rock that is submitted to tectonic loading. Indeed, this numerical method models the crust as an assembly of rigid spheres which are linked by user-defined interactions and reconfigurate very naturally when subjected to loading. Therefore, such approach is adapted to study the evolution of fault geometry through earthquake cycles, since it permits to simulate large displacements of the particles, while avoiding prescribing fault location and geometry, and letting such geometry evolve freely.A 3D parallelepipedic model is designed and then indefinitely sheared by assigning periodic boundary conditions. The particular feature of our model is the implementation of a healing phenomenon, a key process which allows fractured zones to restrengthen after a slip event. During the simulation, the position of particles and the state of their bonds are recorded at regular time intervals; consequently, the shape and dimension of deformation are evaluated, the evolution of fault geometry is monitored, and the stresses in the domain can be measured. Results show a stick-slip behaviour which can be identified as earthquakes separated by locking periods. In addition, the amount of displacement and the rupture surface can be estimated and enable the computation of a magnitude-like quantity. Thus, earthquake-like events seem to follow a magnitude-frequency relationship, and earthquake-like surface deformations are comparable to observations of ground deformation after real size earthquakes. Eventually, the evolution of the fault geometry during the simulation is also scrutinized.
Bridging Field Surveys and Remote Sensing for Enhanced Landscape Feature Analysis in EU Agriculture
Authors: Musavi Talie , Skøien Jon , Czúcz Bálint , Hagyo Andrea , Sedano Fernando , Martinez-sanchez Laura , Koeble Renate , van der velde Marijn , Terres Jean-Michel , D'andrimont Raphaël d’Andrimont
Published: March 2024

This study conducts a comprehensive comparison of landscape feature data derived from different sources — Small Woody Features (SWF) product from Copernicus Land Monitoring system, LUCAS Landscape Feature (LF) Module, and LUCAS Transect Module — in EU agricultural landscapes. Additionally, we consider the European Monitoring of Biodiversity in Agricultural Landscapes (EMBAL) project's approach of in-situ data collection for land cover, landscape elements, and biodiversity. This approach offers a promising avenue for integrating detailed field survey data with broad-scale remote sensing observations. Furthermore the EMBAL project has the potential to enhance the previously mentioned datasets by incorporating additional information, such as the nature value of all surveyed land units, habitat types or pollination potential among others. This inclusion could contribute to having better insights  into the ecological significance and monitoring of agricultural landscapes. Our analysis further explores the potential of incorporating cutting-edge datasets for enhanced monitoring of landscape features. Specifically, we consider the high-resolution (3-meter) dataset from Liu et al. (2023), which presents a detailed canopy height map and quantifies tree cover and woody biomass across Europe. We critically assess the strengths and limitations of each source: SWF's remote sensing foundation provides broad coverage but focuses only on woody features, the LUCAS LF Module combines photo-interpretation with field survey for a more detailed typology, and the LUCAS Transect, though discontinued, offered valuable field data for linear features. Strategies for monitoring landscape features have been considered for a long time, but are continually updated with the latest available data and methods. A comprehensive comparison and evaluation of the new data sources has not yet been carried out. Our study aims to identify complementarities between the different datasets to  improve both quantitative and qualitative monitoring of landscape features informing sustainable agricultural practices and biodiversity conservation strategies.
Significant changes in the light absorption ability of BC-containing particles between the cold seasons of 2016 and 2022 in Beijing
Authors: Hu Min , Hu Shuya , Zeng Linghan , Zhao Gang , Chen Shiyi , Zhao Weilun
Published: March 2024

Black carbon (BC), the most important absorbing component in ambient aerosols, profoundly influences the Earth's radiation system and climate change. Previous studies have demonstrated a decline in the mass concentrations of BC and BC-containing particles in Beijing over the past decade, primarily attributed to stringent emission control measures. In this study, we found a substantial decrease in the mass absorption cross-section (MAC) of BC-containing particles during the cold seasons in Beijing, declining from 9.27 to 7.34 m²/g over a span of seven years. Three reasons lead to the reduction of MAC. Firstly, we observed that the average mass equivalent diameter of the BC cores in 2022 was larger (239 nm) compared to that in 2016 (195 nm). Secondly, the corresponding coating thickness of the BC-containing particles decreased from 1.5 to 1.3. Lastly, significant changes were noted in the chemical compositions of BC-containing particles, with more nitrate and less organic matter (OM) in the coating materials, which led to a diminished absorption ability of BC-containing particles. Our research sheds light on the crucial role of microphysical-chemical properties in determining the absorption ability of BC-containing particles. The results indicate that it is imperative to resolve the MAC of BC in the climate system for better estimating BC’s climate effects. Besides, characterizing the current pollution levels, properties, and impacts of BC-containing particles may help reassess the importance of BC-containing particles in the ambient atmosphere and clarify future research priorities and mitigation measures.
Evaluating Compound Risks of Heatwaves and Droughts on Crop Yield and Food Security in Morocco
Authors: Zellou Bouchra , Bergou El Houcine , El Moçayd Nabil
Published: March 2024

In an era marked by climate change, heatwaves and droughts have increasingly begun to co-occur within a single growing season, significantly impacting crop yields in key agricultural regions globally. Against this backdrop, the current study is dedicated to quantitatively evaluating the effects of these combined hot-dry episodes on agricultural productivity in Morocco, a country where such climatic extremes pose a significant threat to food security and economic stability. Utilizing high-resolution gridded precipitation and temperature data that closely aligns with 29 ground station observations, we calculate the Standardized Precipitation Index (SPI) and the Standardized Temperature Index (STI) across Moroccan arable regions in the agricultural season (September-May) during 1981-2018. Employing a vine-copula conditional probability model, the study explores the complex interactions between drought and heatwaves and their joint impact on vegetation, as indicated by the Normalized Difference Vegetation Index (NDVI). The focus is on identifying the conditional probability of vegetation loss under multiple compound dry-hot episodes. The findings highlight that the combined effects of droughts and heatwaves can have catastrophic consequences for crop yields, especially during the growth season. This underscores the critical need to assess their compound impact on agricultural productivity, rather than examining each factor separately. This study provides a robust understanding of compound hot-dry events and their impacts on crop yields, highlighting the emerging need for comprehensive adaptation strategies that bolster agricultural resilience and support sustainable productivity in the face of evolving climatic challenges.Keywords: Compound, drought, heat waves, NDVI, vine-copula, conditional probability.
Global digital plate model PB2002_CASM and 1°×1° grid velocity field construction
Authors: Xu yantian
Published: March 2024

Based on approximately 15,000 global station coordinates and velocity values, the plate model PB2002_CASM was constructed using actual measured velocity field analysis and supervised clustering analysis based on global PB2002 plate boundary divisions. For plates with more stations, mathematical interpolation algorithms were applied to calculate grid velocity values, including inverse distance weighting, Euler vector method, finite element interpolation method, least squares configuration method, kriging interpolation method, and linear interpolation based on triangulation. For plates with sparse or missing stations, such as in the ocean, singular spectrum analysis was used to extract trend components and obtain station motion speeds, and the PB2002_CASM plate motion model was used to calculate grid velocity values. There are a total of 61,560 1°×1° grids within the global longitude range of -179° to 180° and latitude range of -85° to 85°, which were mathematically interpolated to form 20,071 grid points. The PB2002_CASM plate motion model was used to calculate the velocity of 40,624 1°×1° grid points. The accuracy of the calculated velocity was validated, with a deviation within 1mm, achieving 82% and 89% accuracy in the E and N directions, respectively.
Automatic cloud detection in GHGSat satellite imagery
Authors: Wilson Jake , Sampson Joshua , Girard Marianne , Hammami Kareem , Jervis Dylan , McKeever Jason , Ramier Antoine , Qudsi Zoya
Published: March 2024

GHGSat operates a constellation of satellites that detect and quantify methane and carbon dioxide emissions from industrial facilities across the globe. With twelve satellites in orbit, each making around fifty observations per day, automatic data processing is required.  

A key step in the automation process is the detection of clouds. Identifying pixels that contain clouds or cloud shadow can improve the retrieval quality of cloudy observations and make it easier to detect greenhouse gas emissions.  

In this presentation, we discuss the ML/AI techniques used to detect and segment clouds in GHGSat imagery. We highlight some of the challenges encountered during the creation of training datasets and model training. A first guess at cloud masks is obtained with an unsupervised clustering approach to group pixels of similar intensity. Then, using a dataset of 1000 human-annotated observations, we compare the performance of U-NET and Mask2Former models trained for cloud segmentation. We discuss how the monitoring of training loss can help to identify problematic examples. Finally, we investigate the creation of cloud shadow masks using geometrical projections of the cloud masks, where cloud height is estimated through an intensity-based optimisation. 
Extreme enrichment of lithium in granitic pegmatite by liquid immiscibility
Authors: Chen Xiao-Dong , Chen Bin
Published: March 2024

Single-stage partial melting modeling of meta-sediments or extreme fractional crystallization is inadequate for producing melts with the required Li content (>5000 ppm) for spodumene saturation. Therefore, multi-stage partial melting or fractional crystallization processes have been simulated to achieve the necessary Li content. However, these modeling approaches have overlooked the phenomenon of liquid immiscibility, which has been widely observed in the formation of spodumene-rich granitic pegmatites through studies of melt/fluid inclusions. In this study, we investigate the contribution of liquid immiscibility to the enrichment of lithium in granitic pegmatites by conducting elemental micro-analysis and melt inclusion Raman mapping on multi-stage apatite (Ap) samples from the Dangba large spodumene pegmatite deposit (NW China). The apatite samples are categorized into magmatic Ap1, transitional Ap2, hydrothermal Ap3a, and Ap3b based on the presence of exclusive melt, coexisting melt/fluid, liquid-rich, and vapor-rich fluid inclusions, respectively. The observed increase in Li content from Ap1 (median 43.4 ppm) to Ap2 (median 92.1 ppm) can be attributed to melt-melt immiscibility and subsequent fluid exsolution, as evidenced by the occurrence of coexisting water-rich/-poor melt and fluid inclusions. Furthermore, the significant surge in Li content from Ap2 to Ap3a (median 364 ppm) may result from fluid-fluid immiscibility, supported by the presence of coexisting liquid- and vapor-rich fluid inclusions, complementary negative (Ap3a) and positive (Ap3b) Eu anomalies in the chondrite-normalized rare earth element (REE) patterns, and the lowest Li contents found in Ap3b (median 12.3 ppm) among all apatite types. Considering the partition coefficients of Ap-melt (DLiAp/melt < 0.05) and Ap-fluid (DLiAp/fluid
Macroplastic pollution hotspots across global mountain river catchments
Authors: Zielonka Anna , Liro Maciej
Published: March 2024

Mountain rivers in densely populated areas have recently been reported as substantially polluted by macroplastics [1]. Previous works suggest that macroplastic delivered to mountain river channel can be quickly fragmented to microplastic, because of distinct natural characteristics of  mountain river channel (e.g. high energy of flow, steep gradient, coarse bed sediments).  The produced microplastic (and  related risks) can not only affect mountain rivers but can also be transported downstream to lowland rivers and oceans [2]. The information on local, regional, and global patterns of plastic emission within mountain river catchments is crucial for planning effective mitigation strategies.Here we combine existing databases of river catchments [3] and mismanaged plastic waste (MPW) emission [4] to calculate flux of plastic waste from global mountain river catchments [t yr-1]. Our results demonstrate the highest plastic emissions in Asian mountain river catchments, with the maximum (total MPW 37111630 t yr-1) detected in Himalayas. Similar values were also observed in mountain river catchments in the Chilean Andes; however, the number of hotspots was lower in this region. Mountain river catchments in Europe (especially northern Europe) and Australia are influenced by three times lower emissions of MPW compared to those in Asia and South America. We identified numerous hotspots of MPW emission in mountain river catchments that coincide with areas of extreme rainfall occurrence (particularly in the Southeast Asia region). This spatial correlation may consequently accelerate microplastic production during extreme events and facilitate its downstream transport. The obtained data provide a unique source of information for future detailed research aimed at mitigating the plastic pollution problem in global mountain rivers and highlight areas that require urgent regulations to address the plastic pollution problem. The study was completed within the Research Project 2020/39/D/ST10/01935 financed by the National Science Centre of Poland. References[1] Liro, M., Mikuś, P., Wyżga, B., 2022. First insight into the macroplastic storage in a mountain river: The role of in-river vegetation cover, wood jams and channel morphology. Sci. Total Environ.838, 156354. https://doi.org/10.1016/j.scitotenv.2022.156354[2] Liro, M., van Emmerik, T.H.M., Zielonka, A., Gallitelli, L., Mihai, F.C., 2023. The unknown fate of macroplastic in mountain rivers. Sci. Total Environ. 865, 161224. https://doi.org/10.1016/j.scitotenv.2022.161224.[3] Ouellet, D.C., Lehner, B., Sayre, R., Thieme, M., 2019. A multidisciplinary framework to derive global river reach classifications at high spatial resolution. Environ. Res. Let. 14(2): 024003. https://doi.org/10.1088/1748-9326/aad8e9[4] Lebreton, L., Andrady, A., 2019. Future scenarios of global plastic waste generation and disposal. Palgrave Commun. 5 (6), 1–11. https://doi.org/10.1057/s41599-018-0212-7
Decoding the urban geo-puzzle: navigating geological issues and global challenges through the lens of the Urban Geo-climate Footprint 
Authors: La Vigna Francesco , Lentini Azzurra , Galve Jorge Pedro , Benjumea-Moreno Beatriz , Bricker Stephanie , Devleeschouwer Xavier , Guarino Paolo Maria , Kearsey Timothy , Leoni Gabriele , Romeo Saverio , Venvik Guri
Published: March 2024

At present, worldwide population and economic expansion boosts the demand for environmental resources and urban development. According to the 2022 United Nations World Population Prospect, the global population may reach up to 9.7 billion people by 2050 of which nearly 70% will be residing in urban areas. As a result, the urban setting will become increasingly complex and with more geological and climate negative effects exacerbated by the increasing population, the unequal distribution of economic and energy resources, and the over-exploitation of the environment.To face these worldwide issues, a global approach to knowledge is required with concerted actions by all countries and cities. One possible solution addressing this need could be achieved firstly by classifying cities throughout the world as complex systems defined by geological, subsoil-related climate impact, environmental, and anthropic factors considered in a more holistic way.To achieve this objective, the Urban Geo-climate Footprint (UGF) project, aimed to define a new methodology to classify and cluster cities by geological and climatic point of view.The basic assumption of the UGF approach is that cities with similar geological-geographical settings should have similar challenges to manage, due to both common geological issues and climate change subsoil-related effects. Following this approach, a holistic tool consisting in a complex spreadsheet has been developed and applied to several European cities, in collaboration with several Geological Surveys of Europe.It is demonstrated as the Urban Geo-climate Footprint tool is currently capable of providing a semi-quantitative quick representation of the pressures driven by geological and climatic complexity in the analysed cities, providing for the first time such classification for the urban environment.Through the wide application of this methodology several benefits could be reached as the general awareness increase of non-experts and the enhanced reading-the-landscape capacity of decision makers about the link between geological setting and the increase in pressures due to climate change and anthropogenic activity.Furthermore, the UGF approach would facilitate the possibility to exchange best practices among similar cities for planning purposes, and it would support the decision processes to define and differentiate policies and actions, also supporting policy and cooperative geoscience and climate justice.
Harnessing biocrust-isolated bacteria from semiarid soils to promote plant growth in ecological restoration
Authors: Roncero-Ramos Beatriz , Pagli Carlotta , Maggioli Lisa , Pajuelo Eloisa , Canton Yolanda , Muñoz-Rojas Miriam
Published: March 2024

Restoration of drylands is crucial to reverse global land degradation because these areas cover around 40% of the Earth surface and host one third of the world population. Restoration efforts are often unsuccessful in drylands and alternative approaches need to be developed, i.e., biocrust-based restoration, to promote plant growth and increase soil fertility and stability. In this research, we cultured several biocrust-forming organisms to inoculate them on degraded soils. We designed a more effective inoculum based on biocrust-forming heterotrophic bacteria with plant growth promotion properties (PGP) and key enzymatic activities. We hypothesised that inoculation of native seeds with a consortium of selected heterotrophic bacteria would enhance seed germination and establishment. We sampled incipient and developed biocrusts from three study sites located in semi-arid areas from SE Spain, and isolated 48 bacterial strains. We performed a screening within the bacterial collection to find those strains with key PGP properties and enzymatic activities. Specifically, we analysed their capacity to fix N2, solubilize P and K, produce biofilms, auxins and siderophores, and the extracellular activity of DNAse, amylase, protease, catalase, and lipase. Then, we assessed the best performing bacterial strains for co-culturing to avoid possible antagonistic effects and identified them by sequencing the 16S rRNA gene. The next step of this project will focus on assessing the effects of seed pelleting with the best-performing consortium on germination and establishment of native plants.
Monitoring urban agriculture: a nature-based solution to transform city food systems
Authors: Eiter Sebastian , Fjellstad Wendy , van Schaik Loes
Published: March 2024

Urban agriculture is a nature-based solution to increase the economic, social and environmental sustainability of cities and city food systems. However, sustainability is difficult to measure, and there is therefore discussion about whether urban agriculture really contributes positively to sustainability. Monitoring data could provide evidence of the impacts of urban agriculture and help inform decision makers about whether and where to prioritise different forms of urban agriculture above competing interests.Using case examples from five European cities, we identified the challenges involved in monitoring urban agriculture, from selecting indicators and gathering data, to using the results. We found large differences in approach in terms of what topics to monitor and who was responsible, who gathered the data and when, what data was recorded and how they were stored, and how findings were disseminated or published. Based on these experiences, we recommend stronger involvement of existing interest groups and educational institutions in monitoring urban agriculture, and promotion of convenient tools for data collection by citizen science and for long-term data storage.
Secondary ice production over the Southern Atlantic Ocean: linking satellite data with aircraft observations
Authors: Aboel Fetouh Yasmin , Cermak Jan , Hoose Corinna , Järvinen Emma
Published: March 2024

In the past, numerous airborne in-situ measurements of mixed-phase clouds have exhibited a clear discrepancy between the observed ice particle and ice nucleating particle (INP) number concentrations of up to four orders of magnitude, with the highest differences observed in marine clouds. This suggests that primary ice nucleation is not the dominant source of cloud ice and that secondary ice production (SIP) plays a significant role in governing the ice phase in these clouds. Based on laboratory and field observations a number of SIP mechanisms have been hypothesized. However, most of these mechanisms are not well quantified and, therefore, only a few SIP mechanisms are included in weather models so far.In our research, we aim to spatially extend the observations from aircraft campaigns by linking them to satellite data. Here we will show the work done linking the albedo and brightness temperatures from the 16 available spectral bands of Himawari-8, ranging from 0.47 – 13.3 µm, with the ice particle number concentrations observed during the SOCRATES campaign in low-level boundary layer clouds over the Southern Ocean. Finally, we employed multiple linear regression machine learning techniques and also made use of the SOCRATES campaign lidar/radar onboard.
M-Matisse Crosslink experiment MaCro: an intersatellite radio link for the sounding of the Martian atmosphere
Authors: Pätzold Martin , Andert Tom , Imamura Takeshi , Ando Hiroki , Genova Antonio , Hahn Matthias , Noguchi Katsuyuki , Oschlisniok Janusz , Peter Kerstin , Tellmann Silvia
Published: March 2024

The "Mars Magnetosphere ATmosphere Ionosphere and Space-weather SciencE (M-MATISSE)" mission, currently in Phase A study by the European Space Agency (ESA), is a Medium-class (M7) candidate. M-MATISSE aims to unravel the intricate and dynamic couplings of the Martian magnetosphere, ionosphere, and thermosphere (MIT coupling) in relation to the solar wind (i.e., space weather) and the lower atmosphere. This two-spacecraft mission involves both spacecraft carrying an identical payload suite, each following different orbits with an apocenter at 3,000 km and 10,000 km altitude, and a pericenter at 250 km altitude. The intersatellite radio link, MaCro, operates at two frequencies to probe the ionosphere and atmosphere of Mars during occultation, as one spacecraft disappears behind the planetary disk as seen from the other spacecraft. The instrumentation comprises two transceivers at UHF and S-band, stabilized by an ultrastable oscillator on both spacecraft each. The observables include the shift of the carrier frequencies caused by the bending of the radio ray path in the atmosphere/ionosphere. Onboard data pre-processing precedes the transmission of telemetry to Earth. The orbits allow about eight occultations events (ingress or egress) on average per day starting at an altitude of 1000 km.
The field monitoring and analysis of carbon emissions in the Three Gorges Reservoir: Review and outlook
Authors: Li Zhe , Liu Yang
Published: March 2024

 Since the impoundment in 2003, the flux of CO2, CH4 in the Three Gorges Reservoir has changed significantly compared with the pre-impoundment status. How to understand and evaluate the influence of the construction and operation of the Three Gorges Reservoir on the CO2, CH4 and other greenhouse gas fluxes has attracted much attention. In this paper, we reviewed the experience of monitoring and analysis of CO2, CH4 fluxes in the reservoir since 2009. At present, air-water diffusion was the major pathway for carbon emissions in the reservoir. Terrigenous organic carbon input was the main carbon source leading the production of CO2 and CH4 in the reservoir. Yet, the contribution of autochthonous organic carbon seemed to be with growing significant. Compared with pre-impoundment status, a net increase of greenhouse gas emissions in the Three Gorges Reservoir is evident. Flooding accounted for about 20% of the net increase of the reservoir formation. Anthropogenic pollution in the reservoir region did not significantly to the net increase of CO2 emissions. In addition, the dam acting as barriers and reservoir aquatic ecosystem reconstruction were major contributors for the net greenhouse gas emissions. The past decade sampling campaigns and research promoted the improvement and optimization of monitoring system of the greenhouse gas emissions in the Three Gorges Reservoir. Application of new monitoring methods and technologies also provided support and reimbursement. However, the hydro-ecological mechanism driving the carbon cycle in the reservoir under complex hydrological environment is still unclear, which is a difficulty in the long-term trend prediction of the reservoir carbon flux. In the future, innovation of monitoring technology will be applied to promote the accurate calculation of the carbon flux of the Three Gorges Reservoir. It is still urgent to put forward more scientific and effective models or methods to support the long-term trend prediction and serve the reservoir carbon management.