bluuebunny/crossref_metadata_2025 huggingface dataset:
Near-bed flow directions under varying ice cover of a meander bend in 2016–2024
Authors: Lintunen Karoliina , Lotsari Eliisa , Takala Tuure , Blåfield Linnea , Kasvi Elina , Alho Petteri
Published: March 2024

Currently, in the northern hemisphere, ice cover forms annually on rivers located in high latitudes. However, in the context of future climate changes, this natural phenomenon may undergo alterations, resulting in later ice formation and earlier ice breakup compared to traditional patterns. These changes affect the flow characteristics of rivers and, consequently, impact river environments, especially sediment transport, nutrient transport, and aquatic habitats. While there has been an increase in field measurement-based studies during past decades, our understanding of the effects of river ice cover on flow dynamics within natural environments remains constrained. Specifically, the influence of ice cover on near-bed flow characteristics has been relatively underexplored due to the difficulties in obtaining accurate data in such conditions.When ice cover forms in a river, it creates an additional roughness layer compared to open-channel conditions. This roughness layer alters flow conditions by creating an asymmetrical flow structure. Under a fixed ice cover, flow velocity increases, and maximum velocities might be higher than under similar discharge conditions in an open channel. The flow gradient near the riverbed is notably different in an ice-covered channel than in an open one. In this study, we aim to 1) detect the impacts of ice cover on near-bed flow direction and 2) compare the effects of different riverbed roughness on near-bed flow conditions. The aim is to assess how ice cover and riverbed roughness alter flow characteristics and quantify the effects that might occur when river ice is not present in a similar form to before.The study site is a meander bend of the sub-arctic Pulmanki River, located in Northern Finland. The Pulmanki River undergoes annual freezing, with the ice-covered season typically extending from October through May. Field measurements have been conducted during the ice-covered low flow period spanning from 2016 to 2024 using ADCP (Acoustic Doppler Current Profiler) and ADV (Acoustic Doppler Velocimeter). Near-bed flow directions are analysed based on the comparison of different field measurements. Analysis of the effects of different riverbed forms, roughness,  and prevailing ice conditions on flow characteristics is conducted. The results of this study contribute to the understanding of river ice processes and, therefore, help improve the management of river systems under a changing climate.
Recalibration of extreme multi-decadal trends in the North Atlantic Oscillation.
Authors: Eade Rosemary , Stephenson David B. , Scaife Adam A. , Smith Doug M.
Published: March 2024

The historical variability of the winter mean North Atlantic Oscillation (NAO) has featured periods with large multi-decadal trends which are not well represented by coupled general circulation models (CGCMs), consistent with a lack of autocorrelation in the winter mean NAO index series. Post-processing “reddening” methods are proposed, using stochastic model theory to make the autocorrelation structure of the CGCM NAO index match that of the observed NAO. Using CGCMs from the Coupled Model Intercomparison Project Phase 6 (CMIP6), these recalibration methods are shown to successfully improve the autocorrelation structure of the NAO and in turn the simulation of extreme trends. The 1963-1993 NAO trend is the maximum 31-year trend in the historical period, but without reddening the CGCMs underestimate the likelihood of this trend by a factor of ten. CMIP6 future projections show a small systematic increase in long-term (2024-2094) NAO ensemble mean trends relative to the magnitude of the radiative forcing from ‑0.09 to 0.16 hPa/decade (range for low to high radiative forcing scenarios). This range is doubled after reddening, becoming ‑0.24 to 0.35 hPa/decade. There is also a related shift in the distribution of extreme 31-year NAO trends, which is more clearly apparent after reddening. Near-term projections of the next 31 years (2024-2054) are less sensitive to the future scenario. After reddening they still show weak-to-no forced trend in the models but have a 74% larger ensemble range (around +/- 1 standard deviation per decade). This level of internal variability could increase or decrease regional climate change signals in the Northern Hemisphere by magnitudes that are greatly underestimated when using raw climate model output.
A passive tracer perspective on the origin and evolution of tropical cirrus clouds 
Authors: Gasparini Blaž , Blossey Peter N. , Voigt Aiko , Atlas Rachel , Krämer Martina
Published: March 2024

The processes controlling tropical cirrus clouds are poorly understood, contributing to significant uncertainty in estimating how clouds respond to global warming. Much of this uncertainty stems from a lack of knowledge about the cirrus life cycle. Not knowing how cirrus clouds evolve also makes it hard to determine the fraction of clouds that comes from deep convective outflow compared to those formed by in situ ice nucleation at temperatures colder than -40°C. These two types of clouds are controlled by different processes that may operate differently in a warmer climate, making it even more important to assess their origin.We implement passive tracers in the cloud-resolving model SAM used in a tropical channel setup to track the 3D evolution of cloudy parcels from two different perspectives:A detrainment perspective, useful for tracking the evolution of anvil clouds.
An ice nucleation perspective, useful for following the evolution of in situ cirrus.
Using the detrainment tracer, we can accurately determine how long it's been since an air parcel left a deep convective plume. Our analysis shows that freshly detrained air parcels consist mainly of many large ice crystals with radii of 30-80 μm. These quickly fall out of the atmosphere, resulting in aged anvils containing fewer and smaller ice crystals.The ice nucleation tracer tracks the time after the onset of ice nucleation. This proves valuable for studying the evolution pathways of in situ cirrus ice crystals. Initially, small, freshly nucleated in situ cirrus mostly contain 20-200 ice crystals/liter, occasionally spiking due to relatively rare homogeneous nucleation events. However, the number of ice crystals decreases rapidly, likely because of sublimation, leading to concentrations of < 10/liter in aged clouds.Tracers also help us understand the climatology of cirrus formation. On average, we find that in situ cirrus account for 20% (at T>-50°C) to 70% (at T
Reasons of changes sediment movement near the Rioni river estuary
Authors: Kodua Manoni , Saghinadze Ivane , Tebidze Mari
Published: March 2024

Rioni river, which joins the Black Sea in the territory of Western Georgia, has undergone hydrological changes many times as a result of artificial intervention. Close to its estuary to the south is the port of the city of Poti, whose breakwater was extended by 1.8 km and approached closer to the estuary of the river Rioni.The article discusses the influence of the construction of a breakwater at the mouth of the northern channel of the river Rioni on the movement of sediments along the shore.The constancy of sediment mass balance condition was used to study the sediment transport rates in the coastal zone and the change in the topography of the seabed, based on this the equation of water depth change was obtained. The finite element method and Crank-Nicolson schemes are used to solve the developed equations. The seacoast near the Rioni Nabada delta is taken as the research area.Based on the resulting equations, the numerical experiments are conducted using the values of the known hydrological and hydrometric parameters of the Rioni river and the sea coast.The overbank and bank-directed sediment transport rates are determined. The amount of beach-forming sediment imported by the Rioni river is about 4 million m3 per year.Numerical analysis shows that after the construction of the new port breakwater, the impact of southwesterly waves will be weakened to the north, the movement of sediment in the southern direction will be completely blocked, and 0.85 mln m3 volume of solid sediment will begin to settle in the north of the new Breakwater. In the case of the current hydrological and hydrometric parameters of the Rioni River, the accumulation of a large amount of sediment over time will lead to the blocking of the southern branch of the Nabada channel. Accordingly, the total flow of water from the channel will be shifted to the northern branch and the formation of a new delta will begin there.All movement of fine sediments in this direction will be stopped, and solid sediments will begin to settle to the north of the new breakwater after the new breakwater is built. Ultimately, this will lead to the blocking of the southern branch of the Nabada channel. The entire flow of water from the Nabada channel will be diverted to the northern arm, and the formation of a new delta will begin there. The canyon is currently in equilibrium. A reduction in the supply of sediment may cause it to move towards the shore, which will interfere with the normal operation of the harbor.
Virtual geology and virtual field trips
Authors: Carena Sara , Friedrich Anke Maria , Avasthy Apoorv
Published: March 2024

3D visualization skills are essential in geology, but although virtual 3D tools have been available for years, we have yet to fully integrate them in our courses. In addition, physical field trips not only present accessibility problems for students with limited mobility but can be a considerable financial burden on everyone. Covid restrictions accelerated and expanded a project we were already working on: creating a collection of 3D models of rocks and outcrops to be used as a training aid in the classroom. Travel restrictions, which at our institution included a yearlong complete ban of all field courses (including one-day trips), spurred us to expand the original concept to include also a full 3D virtual environment for students to carry out field trips and mapping exercises. In choosing our tools, we considered three factors: costs, time, and level of difficulty. That meant finding commercial software and hardware that was affordable, did not require programming or engineering skills, or special licenses (e.g. pilot license for large drone), using areas for which we already had a significant amount of material, and storing our 3D models on public platforms.We created 3D models of hand samples and of key outcrops at several field locations that we normally visit in both Spain and Germany by acquiring photos and movies in the field using hand-held cameras and a small drone (which in Europe only requires insurance and operator's registration). We then processed imagery to produce scaled and georeferenced models with Metashape Pro. We used 3DVista Pro, originally designed for real estate showcasing, to produce immersive and interactive virtual field trips (VFTs). This software allowed us to link 3D models, which are stored on either Sketchfab or V3Geo, with videos, animations, photos, maps, text, and realistic sounds for each field scene. An e-learning module in the form of quizzes and game-like features can be incorporated too. We put together different types of VFT: show-and-tell standard VFTs and VFTs with a specific theme (e.g. unconformities), field exercises where students carry out measurements and observations both virtually and later in in the field, and complementary material for remote mapping courses. The reception from students has been positive, so we have kept using virtual tools after lockdown ended.
The Leopoldina’s perspective on community and policy advice and the case of Earth System Sciences
Authors: Wetterich Sebastian
Published: March 2024

The Deutsche Akademie der Naturforscher Leopoldina - founded in 1652 - is the world's oldest continuously existing academy of natural sciences and medicine and was appointed as the German National Academy of Sciences in 2008. In this capacity, the Leopoldina is commissioned with two major objectives: (1) representing the German scientific community internationally and (2) providing policymakers and the public with science-based advice. In recent years, the Leopoldina has increasingly focused on several aspects of the Earth System Science including climate change, sustainable development, biodiversity loss, and other challenges of the Anthropocene when human impact became a decisive force whose influence is drastically seen in all spheres of the planet.The development of recommendations for adaptations of the scientific community in teaching and research as well as for societal change and policy-making are ongoing tasks of Leopoldina working groups. Such outcome of the Academy’s work is commonly communicated through rather classical channels such as statements, reports, fact sheets, workshops and symposia. In addition, interactive thematic websites are set up to enhance impact and increase audience.One example is the Academy’s Report on Tomorrow’s Science: Earth System Science – Discovery, Diagnosis, and Solutions in Times of Global Change (2022). The report addresses German geosciences and the need to establish Earth System Science as the future operating framework for both education and research. Intense feedback from the community was received, which encouraged critical discussion. In addition, the main conclusions of the report were taken up by a private foundation, leading in substantial funding of new tenure-track junior professorships of Earth System Science at German universities starting this year. The challenges of the Anthropocene are currently being addressed by a new Leopoldina working group, which is attempting to incorporate interdisciplinary and transdisciplinary approaches into a conceptual and structural framework in order to give new impetus to basic research and tackle societal challenges.In summary, the further development of Earth system sciences as one of the key disciplines to provide understanding and solutions for urgent challenges of our planet’s present and future is in the focus of the Leopoldina activity. It calls for questioning traditional patterns of thinking in teaching and research and building sustainable structures that meet the major challenges. Only in this way is it possible to gain the necessary understanding of the changes in our living environment and to develop a corresponding science.ReferenceGerman National Academy of Sciences Leopoldina (2022). Report on Tomorrow’s Science. Earth System Science – Discovery, Diagnosis, and Solutions in Times of Global Change. Leopoldina, Halle (Saale). 100 pp. https://doi.org/10.26164/leopoldina_03_0059
A Regional Perspective of Storyline Simulations of the Recent European Summer Heatwaves
Authors: Klimiuk Tatiana , Ludwig Patrick , Sánchez Benítez Antonio , Goessling Helge , Braesicke Peter , G. Pinto Joaquim
Published: March 2024

Heatwaves are a major natural hazard affecting Europe, and their maximum temperatures are projected to increase strongly with climate change. In recent years, the event-based storyline approach has proven its applicability for climate change attribution studies. Constraining the large-scale dynamics to that of the recent past serves to separate the thermodynamic effects of increasing greenhouse gas concentrations from the largely uncertain dynamic changes. Within the SCENIC project, the storylines are produced with the spectrally nudged global coupled AWI-CM1 model (90 km horizontal resolution). They are downscaled with ICON-CLM to the Euro-Cordex (12 km) and subsequently to the central European domain (3 km). Using this model chain, we captured the series of European summer heat waves and droughts of 2018-2022. We placed them into the pre-industrial climate and three environments corresponding to +2, +3, and +4 K warmer worlds. We quantified the warming rate per degree of global warming (which sometimes exceeds 2.5 over larger areas) and assessed the role of soil-atmosphere feedback in contributing to these rates. More specifically, for several European heatwaves, we explored the connection of the evaporative regime of a region affected by a heatwave to the region's response to global warming during this event. Taking advantage of the high signal-to-noise ratio of event-based storylines, we add one more dimension - the global warming level - to the scope of land-atmosphere feedback studies.
Assessment of Climate Change on Water Availability in Central Himalayas, Nepal
Authors: Dahal Bipin , Aryal Insaf , Dhakal Naba Raj , Marahatta Suresh
Published: March 2024

The Kaligandaki River Basin (KRB) in Nepal, as one of the Himalayan River Basins, is experiencing severe impacts of climate change on its water resources. In this study, future climate projections from downscaled CMIP6 GCM models were used to evaluate the potential effects of climate change on the hydrological regime of the KRB by developing a hydrological model soil and water assessment tool (SWAT). Multi-site validation approaches were used to address the high spatial heterogeneity of the basin. The performance of the model was excellent, achieving a consistently very good ranking throughout the study, as evidenced by calibration and validation results. Under the intermediate emission pathways SSP245 scenario, the average annual temperature in the basin is projected to increase by 1.5°C, with a maximum rise of 2.8°C during the pre-monsoon season in the far future. In the high emission pathways SSP585 scenario, the average annual temperature is projected to increase by 2.2°C, with a maximum rise of 4.3°C expected during the winter season in the far future. Precipitation is anticipated to increase across all future time windows, with higher magnitudes under the SSP585 scenario. The combined effect of temperature and precipitation increases is expected to increase the discharge of the river. Specifically, discharge is projected to increase by 6% (under SSP245) and 12% (under SSP585) for 2025-49, 14% (under SSP245) and 24% (under SSP585) for the 2050-74, and 23% (under SSP245) and 40% (under SSP585) for the 2075-99 timeframes. The projected changes indicate an overall increase in average annual discharge, with greater increases expected under the high-emission scenario. These findings highlight the significant influence of climate change on the water balance components and hydrological regime of the KRB. Keywords: SWAT, Climate Change, Water Availability, Kaligandaki
Modelling magma-induced surface uplift and dynamic fracturing around laccoliths on the Moon, Mars, and Earth
Authors: Poppe Sam , Morand Alexandra , Harnett Claire E. , Cornillon Anne , Awdankiewicz Marek , Heap Michael , Mège Daniel
Published: March 2024

Dome-shaped uplifted and fractured terrain observed at the surface of the Moon and Mars includes floor-fractured impact craters. Such deformation features are inferred to form by the emplacement and inflation of sill- and laccolith-shaped magma bodies in the shallowest 1-2 km of a planetary body’s rocky crust. Only the final surface deformation features can be observed from space, modelling helps to understand the emplacement dynamics and the deformation of the overlying rock. A mismatch exists, however, between the complex mechanical response of host rocks to magma-induced stresses observed on Earth in exposed volcanic plumbing systems and the linearly elastic deformation assumed by most of the often-used numerical models.We have implemented simulations of the inflation of a laccolith intrusion in a particle-based host medium in the two-dimensional (2D) Discrete Element Method (DEM). Our approach allows us to investigate magma-induced, highly discontinuous, deformation and dynamic fracturing and visualizes the localization of subsurface strain. We systematically varied a range of numerical model parameters that govern host rock strength (bond cohesion, bond tensile strength, bond elastic modulus), and specific gravity known for the Moon, Mars and Earth. For equal rock stiffness and amounts of intruded magma, our model results show that we can expect more vertical surface displacement on the Moon due to the lower gravity there compared to Mars, and Earth. Rock toughness and rock stiffness control the amount of fracturing more than gravity does.We also tested how host rock strengths in our 2D DEM model could be upscaled from intact strengths of rock samples collected at Earth analogue sites, or by implementing a digital crack network that simulates the highly fractured conditions of the intensively impacted Lunar and Martian crusts. Our results show that laccolith inflation in pre-cracked host rocks results in higher surface displacements and a higher amount of magma-induced cracking in broader fractured zones. We expect that our model results will induce a better understanding of the emplacement and architecture of shallow magmatic intrusions below magma-induced uplifted terrain and floor-fractured craters on the Moon and Mars.
Enhanced methane concentrations measured over the Amazon rainforest
Authors: Ort Linda , Röder Lenard Lukas , Hoor Peter , Lelieveld Jos , Fischer Horst
Published: March 2024

Recently, global mean methane concentrations have increased strongly. Methane is one of the most important greenhouse gases and plays a key role in atmospheric chemistry. Especially, due to its long lifetime of approx. 10 years and its significant effect on Earth’s climate change, a detailed knowledge of its source regions and their temporal evolution is crucial.In this study, we present a unique data set of methane measured in situ over the Amazon rainforest region during the wet season in the CAFE Brazil (Chemistry of the Atmosphere Field Experiment) aircraft campaign from December 2022 to January 2023 in Manaus, Brazil. Methane was measured with an infrared quantum cascade laser absorption spectrometer on board the High Altitude and LOng-range aircraft (HALO). These observations show enhanced concentrations of methane in and above the boundary layer of the Amazon rainforest. Locally, dry air mixing ratios of up to approx. 2100 ppbv could be measured up to 4 km of altitude. Detailed analysis shows only a small contribution from anthropogenic sources. Especially over permanent wetlands and deforested areas, the methane concentrations were enhanced. Furthermore, the data has been compared to satellite measurements from the National Oceanic and Atmospheric Administration (NOAA), indicating good agreement in the free troposphere. Nevertheless, the mean levels directly above the Amazon rainforest are approx. 100 ppbv higher than the global background. Moreover, a global distribution based on airborne data from several campaigns (PHILEAS 2023, CAFE Brazil 2022/23, SouthTrac 2019, CAFE Africa 2018, WISE 2017, ATom 2016/17, OMO 2015, ESMVal 2012) shows that the methane surface concentrations over the Amazon rainforest has a local maximum. This calls for more detailed investigations of methane near the surface in the Amazon and raises an important question: Have we underestimated the Amazon rainforest as a significant source of the global methane budget?
Analysis of the Relationship between the Morphological Characteristics of Lightning Channels and Turbulent Dynamics Based on the Localization of VHF Radiation Sources
Authors: Li YuRui , Zhang Yang , Zhang YiJun , Krehbiel Paul R.
Published: March 2024

The different morphologies of lightning channels are caused by different electrical environments within the cloud, the charge distribution determines the lightning channel morphology, and the lightning morphology can reflect the charge structure to some extent. The distribution of charges is mainly determined by the dynamics and microphysical conditions in clouds, and turbulence plays a significant role in the distribution of charges. Due to the dependence of lightning morphology on the distribution of thunderstorm charges, which is regulated by thunderstorm dynamic effects, a relationship can be established between lightning morphology and thunderstorm dynamic effects.In this study, the lightning channel was obtained from three-dimensional radiation source localization data from the Lightning Mapping Array at the Langmuir Laboratory of the New Mexico Institute of Mining and Technology. The fractal dimension was used to characterize the complexity of lightning channels, which was calculated by the box-counting method. The S-band dual-polarization Doppler radar data was used to estimate the cube root of the eddy dissipation rate (EDR, the EDR was estimated using the Python Turbulence Detection Algorithm). The EDR and radar radial velocity were used to represent the thunderstorm dynamic characteristics.Superimposing EDR and radar radial velocities with LMA radiation sources, our analysis shows that the overall morphology and detailed morphology of the lightning channel correspond to different EDR characteristics. Lightning with complex channel morphology has a larger average FD and occurs in regions with large EDRs. In single lightning events, channels that extend directly within a certain height range without significant bifurcation and turning tend to propagate in the direction of decreasing EDRs, while channel bifurcations and turns usually occur in regions with large radial velocity gradients and large EDRs. This study shows the relationship between channel morphology and thunderstorm dynamics and provides a new method for the direct application of channel-level localization data to understand thunderstorm dynamics characteristics.
Quantification of the practical predictability of thunderstorm occurrence using machine learning
Authors: Vahid Yousefnia Kianusch , Bölle Tobias , Zöbisch Isabella , Gerz Thomas
Published: March 2024

While the statistical post-processing of numerical weather prediction (NWP) data constitutes a powerful ingredient of many forecasting suites of severe weather, post-processing for thunderstorm occurrence becomes ever more difficult as the lead time of the NWP forecast increases. In terms of identifying thunderstorm occurrence as a function of lead time, this increased difficulty is reflected in a decay of skill for which even sophisticated machine learning (ML) models cannot fully compensate. In this work, we propose how the time scale of skill decay of supervised ML models can be studied as a function of the spatiotemporal label resolution used for training. If the label is constructed from lightning observations, label resolution is modified by varying the time and radius thresholds by which strokes of lightning are associated with NWP data. We exemplify our method using SALAMA, a feedforward neural network model which we have developed for identifying the probability of thunderstorm occurrence in NWP data. The model has been trained on convection-resolving ensemble forecasts over Central Europe and lightning observations. We show for SALAMA that the time scale for skillful thunderstorm predictions increases linearly with label resolution, which underlines the practical ability of our method to quantify the predictability of thunderstorm occurrence.
Ocean Circulation and Ice Shelf Melting in the Bellingshausen Sea
Authors: White Emma , Jenkins Adrian , Holland Paul , de Rydt Jan , Morales-Maqueda Miguel
Published: March 2024

A modified version of warm Circumpolar Deep Water (CDW) is able to flow onto the continental shelf in the Bellingshausen Sea, leading to high melt rates beneath the floating ice shelves. Data are presented from a 2007 research cruise to the Bellingshausen Sea, during which temperature, salinity and dissolved oxygen measurements were made at 253 stations. These observations provide detailed insights into the physical oceanographic regime of the region and its impact on the ice shelves, particularly in the western Bellingshausen Sea where few other ship-based observations exist. The transport of CDW across the shelf break at Marguerite Trough and Belgica Trough is assessed, as well as the modification of CDW properties as it flows onto the continental shelf. The spatial variability seen in water masses across the Bellingshausen Sea and regional circulation patterns are also evaluated. Finally, we present an assessment of the meltwater production and circulation within the ice shelf cavities.
The mildly explosive to caldera-forming transition at Colli Albani volcano 
Authors: Ágreda López Mónica , Jorgenson Corin , Caricchi Luca , Giordano Guido , Petrelli Maurizio
Published: March 2024

The effusive-explosive transition in mafic systems is a complex and still largely debated phenomenon in volcanology. Understanding this transition is crucial for hazard assessment and risk mitigation since explosive eruptions can pose significant dangers to nearby populations and infrastructure. In this study, we investigate this transition focusing on a natural study case: the Colli Albani volcano. The Colli Albani is an ultrapotassic caldera complex located 30 km SE of Rome. This volcano has exhibited a wide range of eruptive behaviours throughout its history, ranging from effusive activity to highly explosive eruptions (Giordano & CARG Team, 2010). Here, two main eruptive sequences were selected: The Fontana Centogocce formation (SLV) and the Villa Senni ignimbrites (VSN). SLV represents a period of effusive to mild-explosive eruptions and preceded the emplacement of the 50 km3 Villa Senni ignimbrites (VSN), which represent the last caldera-forming event of the volcano.This study integrates field and petrographic observations, clinopyroxene textural and chemistry analyses and machine learning thermobarometry to understand and constrain the variables influencing the shift from mildly-explosive to caldera-forming eruptions. We present a reconstruction of the volcanic plumbing system's architecture and offer insights into how the system rebuilds in its interim after one of these large events. Giordano, G., & CARG Team. (2010). Stratigraphy, volcano tectonics and evolution of the Colli Albani volcanic field. In: Funiciello, R., Giordano. G. (eds). The Colli Albani volcano. Special Publications of IAVCEI, vol 3, Geological Society, London, 43-98.
Climate risk-reduction potential of gridded precipitation data for agricultural index-based insurance development
Authors: Eltazarov Sarvarbek , Bobojonov Ihtiyor , Kuhn Lena
Published: March 2024

Index insurance has been introduced as an innovative and potential solution to mitigate several challenges caused by climate change in the agricultural sector. Despite the promising potential of index insurance, dissemination in developing countries is slow due to a lack of reliable weather data, which is essential for the design and operation of index insurance products. The increasing availability of model- and satellite-based data could ease the constraints of data access. However, their accuracy and suitability have to undergo a thorough assessment. Therefore, this study statistically and financially analyzes and compares the risk reduction potential of index insurance products designed employing various in-situ-, model- and satellite-based precipitation products (e.g., CMOPH, CPC, IMERG, GSMaP, MERRA, GLDAS, ERA5, PERSIANN, MSWEP, and MERRA2). This study employed county-level spring wheat yield data between 1982 and 2018 from 56 counties overall in Kazakhstan and Mongolia. The results showed that in the majority of cases in both countries, the hedging effectiveness of index insurance products designed based on IMERG is the highest. Moreover, among other data sources, the index insurance products designed using the PERSIANN, GLDAS and FLDAS showed higher risk reduction potential. Overall, this study highlights that satellite- and model-based precipitation products have higher accuracy and potential for index insurance design and operation than in-situ-based precipitation data.
Early-Warning Signs for SPDEs under Boundary Noise
Authors: Bernuzzi Paolo , Kuehn Christian , Dijkstra Henk
Published: March 2024

The search of early-warning signs able to predict the approach of a parameter to a deterministic bifurcation threshold is relevant in climate as it aims to enable a proper prediction of qualitative changes in the studied models. The observation of such objects in SPDEs (stochastic partial differential equations) permits the consideration of space variables and the ensuing heterogeneity in the behaviour of their solutions.The presence of Gaussian noise on the boundary of the studied space is used in order to build the signals, whose properties are discussed thoroughly. An example in the form of application of such tools on a climate model is presented and justified. The utility and appropriate use of the results on a more applied perspective are shown.
Understanding the interior magnetic fields of Ganymede using flybys of the Europa Clipper and JUICE missions
Authors: Sharan Shivangi , Bunce Emma , Dougherty Michele , Jia Xianzhe , Kivelson Margaret
Published: March 2024

The interiors of the icy moons of Jupiter hold a key to understanding habitability in the Solar System and beyond. They could serve as prototypes to comprehend similar bodies that might have the potential to sustain life. The magnetic field observations from the Galileo mission between 1996 and 2003 suggest large oceans below the icy crusts of Europa and Callisto and a probable subsurface ocean at Ganymede. It also discovered that Ganymede has an intrinsic magnetic field and a dynamic magnetosphere.NASA’s Europa Clipper and ESA’s Jupiter ICy moons Explorer (JUICE) missions have been designed to better understand and characterise these icy moons. They aim to confirm the existence of a subsurface ocean at the three moons, in particular, Ganymede and Europa, and constrain their internal structure. The missions would also explore the magnetosphere of Jupiter and its interactions within the Jovian system. Ganymede is the largest moon of our Solar System, capable of producing its own dynamo field and possibly possessing an ocean beneath its surface. However, separating the intrinsic field from the induced field is a difficult problem. Galileo measurements provided two models for Ganymede’s overall internal field- a dipole and quadrupole model or a dipole and induction model. Both the quadrupole and induction signals are quite small and well represent the observations together with the dipole field.Latest trajectory information for Europa Clipper assuming an October 2024 launch, and the predicted JUICE trajectory following the successful launch in April 2023 show initial close Ganymede flybys. In this study, we use them to understand their trajectories and highlight their importance in confirming the induced signal and thereby the ocean as well as for modelling the dynamo field. The first 2 Clipper and the first 3 JUICE flybys occur within an altitude of 500 km from Ganymede’s surface and are hence useful for overall internal field modelling. We predict the measurements that would be observed from the two internal sources as well as the external magnetospheric source to better understand the signals and decipher their differences. For the intrinsic and external fields, we use dynamo and magnetohydrodynamic models respectively while for the induced field, we use Jupiter’s background field along with the induction equation at the spacecraft locations.The 5 flybys independently as well as together with the data from the Galileo flybys would enhance our understanding of the different magnetic sources at Ganymede and the fields they produce. These joint early flyby observations will enable us to be better equipped to model the magnetic field components near Ganymede in the orbital phase of the JUICE mission.
Quantifying global biogenic methane emissions from land and freshwater ecosystems across the landscape 
Authors: Zhuang Qianlai
Published: March 2024

Land and freshwater ecosystems play a significant role in affecting the global methane budget. With future warming, the increase of methane emissions could create large positive feedbacks to the global climate system.  We have used observation data of methane fluxes from diverse land and freshwater ecosystems to calibrate and evaluate extant land and freshwater biogeochemistry models of the Terrestrial Ecosystem Model (TEM) and the Arctic Lake Biogeochemistry Model (ALBM) to quantify the global methane emissions for the past few decades and the 21st century in a temporally and spatially explicit manner. Land ecosystems could emit methane from wetlands while uplands could uptake atmospheric methane. TEM simulates that global wetlands emissions are 212 ± 62 and 212 ± 32 Tg CH4 yr−1 due to uncertain parameters and wetland type distribution, respectively, during 2000–2012. After combining the global upland methane consumption of −34 to −46 Tg CH4 yr−1, we estimate that the global net land methane emissions are 149–176 Tg CH4 yr−1 due to uncertain wetland distribution and meteorological input. During 1950–2016, both wetland emissions and upland consumption increased during El Niño events and decreased during La Niña events. For freshwater ecosystems, we find that current emissions are 24.0 ± 8.4 Tg CH4 yr−1 from lakes larger than 0.1 km2. Future projections under the RCP8.5 scenario suggest a 58–86% growth in emissions from lakes.  Warming enhanced methane oxidation in lake water can be an effective sink to reduce the net release from global lakes. Additionally, these studies identify the key biogeochemical and physical processes of controlling methane production, consumption, and transport in various hotspot emission regions.  We also highlight the need for more in situ methane flux data, more accurate wetland and lake type and their area distribution dynamics information to better constrain the quantification uncertainty of global biogenic methane emissions across the landscape.
Climate sensitivity to extreme temperature changes
Authors: Guan Xiaodan , Cao Chenyu , Ma Yanli
Published: March 2024

In recent decades, a high frequency of extreme high temperature has occurred in many regions worldwide with serious impacts on society and the economy. As the temperature increases, the sensitivity of extreme high temperatures to changing thresholds in the northern mid-latitudes exhibits a different performance response. The results of this study show that extreme high temperature in the increasing phase is more sensitive to changes in the threshold in both observations and simulations (the largest difference in the speed of temperature increase occurs at 3.5 days and 25 days/decade), primarily in North America and Central Asia. This finding highlight that the old definition of being in the increasing temperature phase in modern climate history is problematic today. At the same time, when the old base period is selected, the frequency of extreme high temperatures will become a common event (close to 98% in a year) by 2100. Using 1961-1990 as the base period is not suitable for calculating extreme temperatures in the future from the perspective of adapting to climate change. The increasing temperature threshold means there will be more frequent hot days, indicates that agriculture and species will be negatively affected, more wildfires will occur, resulting in increased risks to humanity.
Erasmus+ and eTwinning projects in developing school students' specific skills related to climate change
Authors: Opria Stefana
Published: March 2024

Natural disasters, a consequence of climate change in recent years, are becoming more frequent. We are witnessing more and more earthquakes, floods, and long periods of drought, affecting everyone on the planet. In this context, teaching specific content on climate change to schoolchildren is essential for building specific skills towards protecting nature. In recent years, Erasmus+ projects have become an opportunity for exchanges of experience between educational institutions to support children and young people in developing into responsible adults. Starting in 2021, as a result of the Erasmus+ accreditation obtained, the "Otilia Cazimir" Secondary School is an institution that supports students in the formation of specific skills to prevent natural disasters, a consequence of climate change. Thus, the three projects implemented so far, "Supporting Teachers for Implementing Leadership", "Hands on Our Future" and the one currently underway, pursue the objectives of sustainable development, thus supporting the formation of sustainable communities. The Romanian students, together with students from Germany, Portugal, and Lithuania, and their teachers, carried out activities to understand the effects of irresponsible environmental behavior and the consequences of these actions on climate change. Collaborative videos, inter-school visits, training courses for students and teachers, discussions with experts, and non-formal education clubs are some examples of relevant activities to train primary and secondary school students to develop the necessary skills for a sustainable future. Inclusion of all participants was ensured in the learning experiences, thus meeting diversity and responding to individual needs. In addition, the eTwinning project "Artificial Environment Resistant to Natural Disasters" implemented in the school year 2022-2023 started as a result of the earthquake in Turkey. Romanian students, together with Turkish and Georgian ones, learned more about natural disasters, how they occur, their causes, and how they can be prevented. They created experiments, drawings, videos, posters, and logos to understand how earthquakes, floods, vegetation fires, and droughts occur and proposed specific solutions to prevent them in the future. The results of the projects implemented in our school have been disseminated over time through social media, workshops, posters, and billboards, becoming sources of inspiration for other institutions to teach young generations. Therefore, Erasmus+ and eTwinning projects represent added value in the educational process, being an important contribution to the formation of generations responsible for the environment and climate change. 
Effect of fireworks events on urban background PM2.5 composition:  measurement of trace elements at SORPES during spring festival periods 2016-2018
Authors: Chi Xuguang , Wang Lei , Zhu Caijun
Published: March 2024

  Burning firework is a traditional custom in China during Chinese Spring festival period, and the smoke plums releasing from firework burning are responsible for high concentrations of particles (especially trace metals) and gases. In this work，results from in-situ measurements of chemical components of PM2.5 aerosols and trace gases during three successive spring festival campaigns (2016-2018) are reported. The campaigns were carried out at a regional background station, SORPES, located in the western part of the Yangtze River Delta in eastern China. Table 1. Median value of selected trace metals, PM2.5 mass, organic carbon, elemental carbon, ions and trace gas concentration during firework events (FW) and background (BG) periods in three campaigns. 
 2016
2017
2018
 
FW
BG
FW
BG
FW
BG
ug/m3
 
 
 
 
 
 
PM2.5
63
54
40
63
59
43
OC
12
7.7
6.5
7.8
4.7
4.4
EC
3.4
2.7
1.8
2.8
2.4
2.7
K
3.1
0.8
1.0
0.5
1.2
0.2
Cl
1.2
1.6
1.0
1.0

1.5

0.8
SO4
11
12
9.2
12
12
7.3
ng/m3
 
 
 
 
 
 
Sr
60
8.2
16
5.5
35
7.4
Ba
137
14
33
11
87
17
Cu
26
10
9.4
6.1
50
37
As
36
23
11
15
13
11
Pb
139
83
60
75
60
46
Zn
90
109
70
127
73
84
Fe
338
369
150
265
174
318
V
2.3
0.8
1.9
2.2
0.7
0.6
CO(ppm)
0.83
0.53
0.48
0.64
0.56
0.55
SO2(ppb)
 
 
2.0
3.6
1.4
2.5

Sr/PM(‰)

1.03
0.2
1.01
0.11
0.98
0.2
 Median concentrations of selected PM2.5 chemical species and trace metals are summarized in Table1. Clear elevations of Sr, Ba, Cu, K and Cl were observed during firework event period than background period, while no clear elevation were found for other species. Time series illustrated in Fig.1 suggested that in our case, Sr followed by Ba were recognised as the best fireworks tracers because their concentration were very high during firework episode and comparable with the detection limits of instrument during the background period. Similar founding was also observed in Spain (Moreno et al., 2010). The higher Sr/PM2.5 ratio (Table 1) suggest higher contribution of firework emission pollution to PM2.5 during firework events compare to background period (5 to 10 times).Figure 1. Time series of Sr and Ba during three campaigns in 2016-2018.  Extremely high enrichment factor was determined for Sr, Ba, Cu, Zn and Pb, suggests that they have anthropogenic origin. Mass concentrations of the trace elements and OC, EC data were input into EPA PMF5.0 model to elucidate the possible dominant source. The results suggest that the dominant sources in three campaigns were firework, coal burning, industry, and traffic. Further analysis on PMF and back trajectory statistics are still need to be done.          
On the tectonic and climatic controls to the evolutionary patterns of Andean plant groups
Authors: Acevedo-Trejos Esteban , Braun Jean , Ritter Benedikt , Böhnert Tim , Mosaku Adeniyi , Davies Hannah
Published: March 2024

Life, climate, and landforms interact to shape the biodiversity patterns we observe in Earth’s Mountain regions. Plausible tectonic and climatic explanations have emerged to explain, for example, the evolutionary patterns of Andean plant groups. However, it remains unclear how different tectonic and climatic histories affect the evolution of Andean flora on geological time scales. Here we present the results of numerical experiments using our coupled speciation and landscape evolution model to investigate how tectonics and climate interact to produce distinct evolutionary histories in the Andes. To address this, we first calibrated our model using a Bayesian inversion algorithm with observations of present-day topography and precipitation, paleo-elevation reconstructions, and thermochronological data to calibrate three scenarios with different uplift histories, which were designed based on the literature and named as propagating and compound. The propagating scenario considers the west-to-east propagation of a Gaussian-shaped wave of uplift, which has been shown to adequately approximate the evolution of plateaus. The compound scenario divides the landscape into 6 geomorphic regions, each with its uplift history. Additionally, we tested a third scenario as a control, in which we maintained the present-day topography for the course of the simulation (ca. 80 Myr), which we named static. We ran the eco-evolutionary component of our model in these three distinct uplift scenarios, covering the mountain building of the Andes for the past 80 Myrs, and designed a series of ensemble simulations in which we randomly assigned dispersal and mutation variability to recreate different assemblages with distinct evolutionary histories and evaluate if the different scenarios produce any consistent speciation patterns comparable to reported time-calibrated phylogenies of various plant groups. We found that the uplift scenario with a more complex uplift history, i.e. compound, better agrees with the different observations. This scenario also showed increased diversification during the Miocene (23-4.5 Ma), a feature observed in several Andean plant groups. This demonstrates how diversification constraints obtained from phylogenetic studies can be used to discriminate between conflicting uplift scenarios for the Andes/Altiplano that have been suggested by paleo-altimetry estimates and other geological observations.