bluuebunny/crossref_metadata_2025 huggingface dataset:
Managing participants, expectations and surprises during fieldwork – Experiences from collaborative flood risk management in Ghana
Authors: Höllermann Britta , Ntajal Joshua
Published: February 2023

The PARADeS project uses participatory approaches to contribute towards enhancing Ghana’s national flood disaster risk reduction and management strategy. The project was initiated by practitioners from Ghana and the problem setting was developed during a definition phase of the project. When the project started, commitment and strong partnership and involvement of partners were already established - a prerequisite for collaborative and non-extractive research.Multiple workshops and focus group discussions were ‘successfully’ conducted in collaboration with our local partners. Despite the sound basis of the project (e.g. shared goal(s), strong and committed partnership), we experienced challenges before, during and post fieldwork. In this contribution, we particularly reflect and focus on including and managing different types of participants. On the one hand, we engaged with representatives from different governmental institutions and non-governmental organizations with mostly academic background during the workshops. On the other hand, flood-affected urban and rural citizens with strongly differing educational backgrounds and socio-economic assets elaborated on their flood experiences during the focus group discussions. Here, three main themes and challenges arose:Selection of participants: Identifying blind spots of researchers and local partners, e.g. the risk of missing out marginalized voices,
Expectations management: Coping with expectations of participants and communicating own room of action, and
Feedback processes: Preventing extractive research by feedbacking information relevant to the participants
During the session, these themes are discussed using the guiding principles for fieldwork with participants (see Rangecroft et al. 2020) by highlighting ethics, communication, power dynamics and positionality. For this, we share our experiences and lessons learned e.g. how we deal with the problem of getting a gender balanced participant list or how we manage unexpected structures of focus groups. Furthermore, we would like to share our uneasiness when, for example, a focus group discussion turned into a community talk or unrealistic though understandable expectations were raised. By sharing our successes and pitfalls, we would like to contribute to a broader discussion on how to improve fieldwork, prepare for surprise and, especially, to meet expectations of participants, partners and researchers without compromising each other’s needs and integrity.  Rangecroft, S., M. Rohse, E. W. Banks, R. Day, G. Di Baldassarre, T. Frommen, Y. Hayashi, B. Höllermann, K. Lebek, E. Mondino, M. Rusca, M. Wens and A. F. Van Loon (2020). "Guiding principles for hydrologists conducting interdisciplinary research and fieldwork with participants." Hydrological Sciences Journal: 1-12.
Magmatic Fingerprints of Subduction Initiation and Mature Subduction of the Izu-Bonin-Mariana Subduction Zone: Numerical Modelling and Observations
Authors: Ritter Sandrine , Balázs Attila , Ribeiro Julia , Gerya Taras
Published: February 2023

Subduction of oceanic lithosphere has been proposed as the main driving mechanism for plate tectonics for decades and it represents a key process for the geochemical cycles on Earth. However, the physical processes and melting that occur as the subduction zone began foundering and evolved to reach a mature stage is still debated. The Izu-Bonin-Mariana (IBM) intra-oceanic subduction zone, that represents the boundary between the Pacific Plate and the Philippine Sea, is an ideal natural laboratory to study subduction zone processes from their inception to their stabilization. The rock record produced in IBM reveals a rapid compositional variability in slab-fluid tracers as well as in mantle depletion-enrichment over a short timescale (within 1 to 5 Ma of subduction inception). Despite this geochemical evolution, it is still highly debated whether IBM initiated as a forced or spontaneous subduction zone, i.e. induced by or in the absence of horizontal forcing, respectively.Here, we conducted 2D high-resolution petrological-thermomechanical subduction models that include spontaneous deformation, erosion, sedimentation and slab dehydration processes, as well as melting, assuming a visco-plastic rheology using the i2VIS code. We aimed to model the initiation and the early stage of IBM with ultra-low horizontal forcing and inception triggered by transform collapse. Our new numerical model proposes a viable scenario for the transition from juvenile to mature subduction zone. This evolution includes initiation by gravitational collapse of the slab and the development of a near-trench spreading, the gradual build-up of a return flow of asthenospheric mantle and the progressive maturation of the volcanic arc. Our numerical results of mantle depletion within the mantle wedge and the overall subduction history of IBM are compared further with seismological and geochemical evidences.
Arduino coding in the classroom
Authors: Bouquelle Veronique
Published: February 2023

I recently started using Arduino boards in my physics teaching. I was looking for practical projects for an Applied Science class – which is a small-sized technical section of our school with 10 hours of science a week. It’s in the program to study some electronics, and although coding isn’t included, I feel it my duty to teach the basics. Programming requires a special way of thinking, with its specific structure using loops and variables. It’s a language on its own. Practicing it at a young age gives you an advantage on future learning abilities.The choice of the Arduino board was quite straightforward for me, although Raspberry Pi would also do the job in a different way. Arduino is a microcontroller board barely bigger than a bank card, that connects to all sorts of electronics, sensors, and motors. It collects data in its environment, processes it, and operates a motor or display accordingly. It is cheap, versatile and you find plenty of tutorials online. Light and music setups, robots, automatic watering, smoke detector, persistence of vision globe, lie detector, portable guide for visually impaired people, rotating light-sensitive solar panels, electronic games… the possibilities are endless.Programming an Arduino board can be done either in the Arduino IDE language, itself very similar to C++, or through blocks of words that will then be translated into computer language for you. The many programs available on the Internet usually contain a description for each line of coding. It makes it easy to understand, use, and modify to meet your own needs.To demonstrate the potential of teaching with this microcontroller board, I present in this poster my pupils’ projects. I also show how one can draw, code (in blocks or text), and simulate electronic circuits with Tinkercad, a web-based designing dashboard.
Waveform Tomography of the Antarctic Plate
Authors: Chua Ee Liang , Lebedev Sergei
Published: February 2023

The Antarctic continent is a complex assemblage of geological units, ranging from Archean cratons in the east to a Cenozoic assembly of Mesozoic terranes in the west. Present are also the failed Lambert rift system, the inactive West Antarctic rift system and intraplate volcanism in Marie Byrd Land. Covered almost entirely by ice sheets, Antarctica's highly heterogeneous lithospheric structure and its upper mantle are among the least well-studied regions of the Earth’s interior.The past two decades have seen a significant rise in the number of seasonal and temporary deployments as well as new permanent stations, supplementing and improving the still sparse station coverage in Antarctica. This provided a considerable improvement in both the quantity and quality of seismic data available for the Antarctic continent and its surrounding regions. We assemble a very large dataset of 0.8 million waveform fits, comprising all publicly accessible broadband data in the Southern Hemisphere, with sparser coverage elsewhere, for the best possible sampling of the Antarctic Plate’s crust and the upper mantle.The new S-wave velocity tomographic model of the crust and upper mantle of Antarctica is computed using the Automated Multimode Inversion (AMI) scheme. AMI first extracts structural information from the surface, S- and multiple S-waves as sets of linearly independent equations. These equations are then combined into a single large linear system that is solved to obtain a tomographic model of the Antarctic crust and upper mantle. We observe the clear delineation of East and West Antarctica by a strong velocity gradient that bisects the continent extending from Coats Land to Victoria Land, following the Transantarctic Mountains. West Antarctica is observed to be underlain by low S-wave velocity anomalies connecting the Antarctic Peninsula, the Amundsen Sea Coast and Marie Byrd Land. The highest S-wave velocity anomalies are observed in central-eastern Antarctica, most of which is underlain by thick, cold cratonic lithosphere. Our tomography maps the boundaries of Antarctica’s cratonic lithosphere and, also, substantial intra-cratonic heterogeneity. It also reveals the patterns of the lithosphere-asthenosphere interactions beneath the cratons and the neighbouring Cenozoic terranes and offers new evidence on the origins of the Transantarctic Mountains and the intraplate volcanism in West Antarctica.
Using DAS-fibres at ocean floor and lunar surface
Authors: Landrø Martin
Published: February 2023

We have used two seabed fibre optic cables connecting Ny Ålesund and Longyearbyen at Svalbard, North of Norway, to track several whales for several weeks. Exploiting that we have access to two fibres we demonstrate that it is possible to track several whales in a fairly large region. It is possible to create sound records of whales that can be used for identification and discrimination between various species. The localization method has also been tested by using a small air gun to confirm the localization method used for whales. Examples of earthquake recordings, ship traffic monitoring and distant storms will be shown.Based on the rapid and promising developments within DAS technology, there is a growing interest for using fibre optic cables at the moon. Some challenges and possibilities related to Lunar DAS applications will be discussed.
Linked fire activity and climate whiplash in California during the early Holocene
Authors: Oster Jessica , Homann Julia , de Wet Cameron , Breitenbach Sebastian , Hoffmann Thorsten
Published: February 2023

Recent wildfire activity in semi-arid regions like western North America exceeds the range of historical records. High-resolution paleoclimate archives such as stalagmites could illuminate the link between hydroclimate, vegetation change, and fire activity in pre-anthropogenic climate states beyond the timescale of existing tree-ring records. Here we present an analysis of levoglucosan, a combustion-sensitive anhydrosugar, and lignin oxidation products (LOPs) in a stalagmite from White Moon Cave in the California Coast Range in order to reconstruct fire activity and vegetation composition across the 8.2 kyr event. Elevated levoglucosan concentrations suggest increased fire activity while altered LOP compositions indicate a shift toward more woody vegetation during the event, with the shift in vegetation preceding the increase in fire activity. These changes are concurrent with increased hydroclimate volatility as shown by carbon and calcium isotope proxies. Together, these records suggest that climate whiplash (oscillations between extreme wetness and aridity) and fire activity in California, both projected to increase with anthropogenic climate change, were tightly coupled during the early Holocene.
Changes in intermediate circulation waters along the tropical eastern Indian Ocean during quaternary climatic oscillations
Authors: Le Houedec Sandrine , Tremblin Maxime , Champion Amaury , Samankassou Elias
Published: February 2023

The Indo-Pacific Warm Pool (IPWP) is the warmest and most dynamic ocean-atmosphere-climate system on Earth and has undergone significant climatic changes during the Pleistocene glacial periods (De Deckker et al., 2012; Lea et al., 2000; Russell et al., 2014). During the Last Glacial Maximum, the latitudinal position of the Southern Ocean fronts, both south of Africa and Australia, was shown to be critical in controlling the outflow of warm water of the Agulhas Current from the Indian Ocean and the IPWP area. Yet, there is no direct evidence for such oceanic change on the scale of the Late Pleistocene glacial-interglacial transitions.Here, we combine sea surface temperature proxies (d18O and Mg/Ca) with the neodymium (Nd) isotopic signature to reconstruct changes in climate and oceanic circulation in the eastern tropical Indian Ocean over the last 500 ka. The most striking feature of our dataset is the oscillating Nd signal that mimics the glacial-interglacial cycles. While interglacial periods are characterized by a more significant contribution from the less radiogenic Antarctic intermediate water mass (AAIW, ~ -7 εNd), glacial periods are marked by more radiogenic water mass of Pacific origin (~ -5 εNd). We argue that under global cooling, the northward penetration of the AAIW has weakened due to the general slowdown of the global thermohaline circulation. Furthermore, the oscillating pattern is also recorded in the sea surface temperature and salinity, indicating the settlement of cooler and more saline surface water masses probably linked to a less expanded IPWP and weaker Leeuwin Current during glacial intervals.We suggest that under low AAIW a less intense advective mixing occurred, allowing a deepening of both halocline and thermocline in the tropical eastern Indian Ocean. Our new proxy-derived dataset confirms results from models (DiNiezo et al., 2018), suggesting that these ocean conditions could amplify the externally forced climate changes resulting from drier atmospheric conditions and weaken the monsoon during glacial periods in the Indonesian region.
Combined migrations and time-depth conversions: first results
Authors: Persico Raffaele , Morelli Gianfranco , Esposito Giuseppe , Catapano Ilaria
Published: February 2023

Commonly exploited migration algorithms or also well-established linear inverse scattering algorithms [1] for the focusing of GPR data are often based on the hypothesis of a homogeneous soil. However, this assumption is not valid always, and it provides deformed results when it is applied to image scenarios where it is not valid. More complex models of the scattering can afford the situation of a stratified medium, but only if the layers are flat and parallel to each other these model assumes analytic forms. In any case, commonly available commercial codes do not allow to implement the reflections and refraction of the waves associated to these cases [2]. More recently, time reverse migration algorithms have been introduced. They can account efficiently of non-homogeneous soils, but their performances in case of large and strong scattering targets are not yet completely established and they make use of forward numerical solvers, not all the times available and user friendly. At the conference, we will describe a strategy based on suitable combination of migration results achieved from different homogeneous media, accompanied by a time-depth conversion accounting for the occurrence of different values of the wave propagation velocity in the investigated domain. We will show how an improvement of the imaging result is achieved even in the lack of a correct mathematical model of the scattering phenomenon. Last but not least, the proposed strategy exploits software routines easy to be implemented.
Satellite gravimetry helps monitor the operation of large reservoirs
Authors: Besnier Jessica , Getirana Augusto , Biswas Nishan , Lakshmi Venkataraman
Published: February 2023

All over the world, water levels are constantly changing. From lakes, to rivers, to oceans, the patterns of the water levels change due to different factors. With hydrological extremes increasing in intensity and duration around the world, it is important to understand what changes these levels in order to better predict and mitigate the negative impacts of changing water levels.The goal of this study is to use estimates of terrestrial water storage (TWS) variability from the Gravity Recovery and Climate Experiment (GRACE) satellite mission to predict reservoir operation in Brazil. To do this, reservoir water elevations are derived from multi-satellite radar altimetry (RA) data and used as a proxy of their operation. 30 reservoirs in Southern Brazil are considered. For each reservoir, the Pettitt test was used to identify the point break within the TWS data, and the Mann-Kendall test was used to identify trends before and after these breaks.A machine learning approach was used to reconstruct RA-based water elevations using GRACE data. The approach considered numerous geomorphologic and meteorologic characteristics of reservoirs, including reservoir area, volume, location, extent, depth, drainage area, and elevation, in addition to precipitation and temperature. Break points of time series and trends were also computed for each reservoir to explain why some reservoirs present a better fit than others. The findings of this study will give insight into what variables affect the relationship between TWS and RA height in the Parana Basin in Southern Brazil.
Transport of thiophanate methyl in porous media in the presence of titanium dioxidenanoparticles
Authors: Chrysikopoulos Constantinos V. , Stefanarou Anthi S. , Katzourakis Vasileios E. , Malandrakis Anastasios A.
Published: February 2023

This study investigates the transport of pesticide thiophanate methyl (TM) as well as the co-transport of TM and titanium dioxide (TiO2) nanoparticles in a water saturated column packed with quartz sand under various water conditions. Several ionic strengths (Is) (1, 10, 50 and 100 mM) and pH (3, 5, 7, 10) values were examined. The results from the transport experiments  were fitted and analyzed with the use of the ColloidFit software, while the results from cotransport experiments were fitted with a modified mathematical model of Katzourakis and Chrysikopoulos (2015). The results suggested that the lowest mass recovery rate was for the co-transport experiments with the addition of NaCl. It was shown that TM has a weak affinity for sand but a relatively strong affinity for TiO2 at high Is and acidic pH. Furthermore, salinity was shown to have significant effects on TM removal.
Influence of root systems of different tree species and their exudates in formation of properties of forest soils
Authors: Staszel-Szlachta Karolina , Błońska Ewa , Lasota Jarosław
Published: February 2023

The root systems of trees, through the production of biomass and through their exudates, affect the properties of forest soils. There is a lack of basic knowledge about the influence of root systems of basic forest-forming tree species on the properties of forest soils. The purpose of our study was to determine the influence of the roots of six tree species and their root exudates on shaping the physicochemical and biochemical properties of soils. The study included deciduous tree species (ash, hornbeam, oak, beech) and coniferous trees (pine, European larch).  The survey was conducted in 2022 in the Miechow Forest District (southern Poland). Each tree species was represented by 5 study plots. The research included analysis of root systems and analysis of surface properties of soil horizons. Exudates were collected using a culture-based cuvette system. Additionally, we determined the morphology, and production of fine roots.  Basic physicochemical properties and the activity of enzymes involved in the cycling of C, N, and P were determined in the soil samples. The tree species studied have different morphological characteristics of roots and differences in the exudates secreted. In addition, the studied species differ in the rate of growth of root systems.  Significantly higher amounts of secreted carbon from roots were recorded in ash, which had a positive effect on the increase in enzymatic activity.  The amount of C from exudates showed a positive correlation with CB, BG and PH activity. The activity of the enzymes studied also correlated with the morphological characteristics of the roots. Root systems also influenced the formation of basic physicochemical properties such as C and N content.
Sub-seasonal variability of Asian summer monsoon transport of aerosols and CO to the UTLS in the context of recent aircraft observations in the Asia
Authors: Chin Mian , Bian Huisheng , Colarco Peter , Lait Leslie , Chen Gao
Published: February 2023

We present our study on the sub-seasonal variability of UTLS aerosols and CO that is a result of the variability induced by the sub-seasonal variability of the Asian summer monsoon dynamics. We use the NASA global model GEOS simulations that incorporates emissions from anthropogenic, biomass burning, volcanic, and other natural sources to simulate CO, aerosols and related gases and the model experiments separating source types (anthropogenic, biomass burning, volcanic) and source locations (East Asia, South Asia). With model results and observations from recent aircraft measurements (StratoClim, ACCLIP) in the UTLS over the Asian summer monsoon regions, we will discuss (1) the sub-seasonal variability of transport pathways of surface-generated pollutants to reach UTLS, and (2) sub-seasonal variation of aerosol composition that is determined by the variability of source type originating in different locations.
Riverine flood risk in municipalities of Slovakia
Authors: Vojtek Matej , Vojteková Jana
Published: February 2023

Integrated flood risk assessment is based on a multidimensional definition of flood risk, i.e. the extent of flood losses depends not only on the flood hazard itself, but also on the vulnerability of the social, economic, and environmental system to flooding. This study aims at the riverine flood risk mapping and assessment in municipalities of Slovakia. The riverine flood risk index (RFRI) was determined for 2,927 municipalities of Slovakia as a synthesis of the riverine flood hazard index (RFHI) and the riverine flood vulnerability index (RFVI) using the spatial multi-criteria analysis and geographic information systems (GIS). The RFHI was calculated based on eight indicators representing the riverine flood potential: number of flood events, slope, curvature, average annual maximum 5-day rainfall, river density, lithological rock types, soil texture, and land cover. Moreover, the RFVI was calculated based on seven indicators representing the social and economic vulnerability of municipalities: population density of urban areas of municipalities, share of population included in the age category 65+ from the total population of municipality, share of unemployed persons from the total number of economically active population in municipality, share of the Roma ethnicity from the total population of municipality, number of buildings within 100 m from a river, length of roads within 100 m from a river, and number of bridges in a municipality. The result of the Pearson correlation between individual indicators and the number of flood events in municipalities was used to determine the importance of indicators, which was subsequently used for assigning the indicator weights applying the rank sum method. The RFHI and RFVI for each municipality were calculated as the aggregation of the respective weighted indicators. The multiplication of the RFHI and RFVI resulted in the final RFRI. Based on the results obtained, the very high and high classes of RFHI contained 839 municipalities, which are located mostly in northern and eastern Slovakia and partly also in western and central Slovakia. The very high and high classes of RFVI included 817 municipalities, mainly, in northern and central Slovakia and partly also in western and eastern Slovakia. The highest RFRI values were recorded mostly by the municipalities in northern, central, and eastern Slovakia and partly also in western Slovakia. The very high and high risk of riverine flooding was recorded in 700 municipalities, i.e. these municipalities are included in the very high and high classes of RFRI. The results achieved in this study are useful, on one hand, for local self-governments and actors responsible for flood risk management, but more importantly for cyclic updating of the Preliminary Flood Risk Assessment in Slovakia under the EU Floods Directive. This work was supported by the VEGA agency under the grant number 1/0103/22 through the project entitled "Spatio-temporal Changes and Prediction of Flood Risk in Municipalities of Slovakia".
Effects of solute release position on transient solute dispersion across the sediment-water interface: A modeling study
Authors: Xu Pengcheng , Wang Lingling , Xu Jin , Wang Zhe , Chen Han , Wu Mengtian
Published: February 2023

Understanding the fundamental mechanisms of solute transfer across the sediment-water interface (SWI) is essential for comprehending river functioning. Considering the stochastic and complex pollutant emissions across the SWI, we investigate the effects of release position on the solute transport in this work. Linking turbulent momentum and solute transport in the hyporheic zone through numerical modeling. Simulation results reveal that the location of the point source release determines the initial convection and dispersion intensity, which in turn affects the process of solute dispersion across the SWI. The location of solute release can affect hyporheic mixing processes more significantly than changes in streambed permeability. The penetration of turbulence into the streambed directly controls both interfacial exchange and mixing within a transition layer below the SWI, which is consistent with previous findings. In addition, the finite-time Lyapunov exponents are used to describe the lagrangian coherent structures of the flow field in the whole process, which provides a new perspective to reveal the mixing process of solutes across the SWI.AcknowledgmentsThis research was funded by the National Key R&D Program of China (2022YFC3202605), the Fundamental Research Funds for the Central Universities (B200204044), the Research funding of China Three Gorges Corporation (202003251).
Variety and diversity in climate and ocean literacy activities
Authors: Promduangsri Pariphat , Promduangsri Pimnutcha , Alvarez de la Campa Stacey , Bolouri Farhad , Gökçekuş Hüseyin
Published: February 2023

Climate change (CC) and ocean degradation (OD) affect every living species on the planet.  CC and OD negatively impact marine life, plant life, soils and agriculture, animals and humans.  One way to fight against CC and OD is by learning from climate and ocean programmes and activities, both formal and informal.Climate and ocean education is crucial as it helps people to better understand how climate is changing and how the ocean is degrading.  Such education will thus provide know-how and ways to act for individuals and for communities to adapt to and mitigate CC and OD.In this poster, we survey some of the variety and diversity of climate and ocean literacy activities at personal and institutional levels.  At the personal level, we will show experiences that help people to learn about CC and OD, such as work with indigenous communities, attending conferences and studying in MOOCs.  Examples at the institutional level include working in an environmental association, attending workshops (eg, EN-ROADS) and participating in a participatory simulation (eg, IOCS).We invite you to visit our poster and share your climate and ocean literacy activities.----------------------------------------------------------------------ReferencesUNESCO. (n.d.).  Climate change education.  Paris, UNESCO. https://www.unesco.org/en/education/sustainable-development/climate-changeUnited Nations. (n.d.).  Education is key to addressing climate change.  United Nations. https://www.un.org/en/climatechange/climate-solutions/education-key-addressing-climate-change
Long-term field experiment for exploring effects of Biochar on soil processes in winter wheat-summer maize cropping system in Northern China
Authors: Li Guitong
Published: February 2023

In June of 2009, a long-term field experiment was conducted in the Shang-zhuang Experimental Station of China Agricultural University (CAU) at Haidian District, Beijing (N 40° 08′ 21″, E116°10′ 52″). The soil is calcareous fluvisol and the field located on an alluvial plain at an altitude of 51 m and a shallow groundwater level of 1-1.5 m. The region has a typical continental monsoon climate with an annual average air temperature of 11.6 °C and an annual average precipitation of 400 mm. The typical cropping system is winter wheat (from October each year to June of the following year) and summer maize (from June to September each year).There are 6 treatments in the experiment: chemical fertilization with returned-straws both of wheat and maize was as experiment control (CK, or B0); 30, 60, and 90 t/ha Biochar were applied on the base of CK, coding as B30, B60, and B90; meanwhile, returning straw of wheat and maize but no chemical fertilizer (WM) and only wheat straw returning (W) were also as a treatment. After application of Biochar in June of 2009, all other agronomic practices were same as local real production way.Although the field experiment is going on, we have got important conclusions till now, that are, (1) About 40% biochar lost from the 0-20 cm soil layer during the first 5 years after Biochar application; (2) No more than 25% biochar located in the aggregates >53 um in the 5th year after Biochar application; (3) Biochar decreased the turnover of C in the returned-straw to SOC by 11% to 31% during the first 5 years after Biochar application, and the main decrease occurred from the wheat straw; (4) Biochar decreased soil labile organic carbon pool about 50%; (5) Priming effect caused by Biochar was positive during the first 3 years but negative during the 3 to 5 years after Biochar application; (6) Biochar decreased wheat-straw-derived SOC in larger aggregates, but accumulated more in smaller aggregates; (7) Biochar increased soil pedogenic carbonate content in the 0-20 cm soil layer during the 8 years after Biochar application; (8) Biochar amendment significantly increased subsoil pH (0.3−0.5 units) during the 10 years after biochar application; (9) The transported Biochar in subsoil acted as nuclei to precipitate pedogenic carbonate; (10) Biochar amendment enhanced soil inorganic carbon pool by up to 80% in the 2m soil profile. All these results have been published on international journals such as Science of the Total Environment, Soil Tillage Research, CATENA, Journal of Soils and Sediments, Journal of Integrative Agriculture, Agricultural Ecosystems & Environment, Soil Use Management, and Environmental Science & Technology.
Northwestward migration of the East Asian monsoonal limit during the Medieval Warm Period
Authors: Jiang Jiawei , Chen Lin , Zhou Aifeng , Liu Zhonghui
Published: February 2023

The East Asia summer monsoon variability and changes in monsoonal rainfall are critical for hydrology and ecology conditions in water-stressed regions of northern China. Due to complex interactions of monsoonal and westerlies circulation, hydroclimatic conditions at the boundary between two circulation systems, commonly defined as the 300 mm annual rainfall line, remain poorly understood. Here we report alkenone records (UK'37, %C37:4, and RIK37) from Lake Eastern Juyanze in northern China to assess temperature and hydrological changes in marginal monsoon region over the last millennium. Our records show wet conditions during the Medieval Warm Period, with the presence of alkenone C37:3 isomer at the interval of ~ 700-1,050 AD and thus evident freshening of lake water, and dry conditions during the Little Ice Age. The paired records follow the warm-wet and cold-dry association in monsoonal regions over the last millennium, opposite to the warm-dry and cold-wet association in westerlies region, although Lake Eastern Juyanze is located to the northwest of current monsoonal limit. Our results, together with other hydrological records from marginal monsoon regions, collectively indicate northwestward migration of East Asia monsoonal limit during the Medieval Warm Period associated with relatively high solar irradiance and enhanced summer monsoon circulation. Findings in this study highlight the complexity of hydroclimatic changes in marginal monsoonal regions, and further investigations focusing on the Holocene epoch are highly recommended. 
Radar-derived ice fabric anisotropy and implications on flow enhancement along the Thwaites Glacier Eastern Shear Margin
Authors: Young Tun Jan , Martin Carlos , Jordan Thomas , Zeising Ole , Eisen Olaf , Christoffersen Poul , Lilien David , Rathmann Nicholas
Published: February 2023

Glaciers and ice streams account for the majority of ice mass discharge to the ocean from the Antarctic Ice Sheet, and are bounded by intense bands of shear that separate fast-flowing from slow or stagnant ice, called shear margins. The anisotropy of glacier ice (i.e. a preferred crystal orientation) stemming from high rates of shear at these margins can greatly facilitate fast streaming ice flow, however it is still poorly understood due to a lack of in-situ measurements. If anisotropy is incorporated into numerical ice sheet models at all, it is usually as a simple scalar enhancement factor that represents the "flow law" that governs the model's rheology. Ground-based and airborne radar observations along two transects fully crossing the Eastern Shear Margin of Thwaites Glacier reveal rapid development of highly anisotropic fabric tightly concentrated around a lateral maximum in surface shear strain. These measurements of fabric strength at the centre of the shear margin are indicative of a horizontal pole configuration, which potentially represents ice that is “softened” to shearing in some directions and hardened in others. The resulting flow enhancement revealed by our results suggest that the viscosity of ice is highly variable and regime-dependent, and supports the importance of considering anisotropic flow laws to model the rheology of ice sheets.
Volcanism of Mount Fuji activated by the 2011 Japanese large earthquakes
Authors: Nanjo Kazuyoshi , Yukutake Yohei , Kumazawa Takao
Published: February 2023

The relation between earthquakes and volcanic eruptions, each of which is manifested by large-scale tectonic plate and mantle motions, has been widely discussed. Mount Fuji in Japan last erupted in 1707, paired with a magnitude (M)-9-class earthquake that took place 49 days prior. Motivated by this pairing, previous studies examined the effect of both the 2011 M9 Tohoku megaquake and a triggered M6-class earthquake 4 days later at the foot of the volcano on Mount Fuji, although no volcanic eruption was reported. More than 300 years already have passed since the last 1707 eruption, and although consequences to humans and society caused by the next eruption are already being considered, the implication for future volcanism remains uncertain. Here we show how volcanic low-frequency earthquakes (LFEs) in the deep part of the volcano revealed hitherto-unrecognized activation immediately after the foot earthquake. Our analyses using statistical methods based on the matched-filtering, the epidemic-type aftershock sequence (ETAS), and the Gutenberg-Richter frequency-magnitude distribution of LFEs show that despite an increase in the rate of occurrence of LFEs, these did not return to pre-earthquake levels, indicating a change in the magma system. Our results demonstrate that the volcanism of Mount Fuji was reactivated by the foot earthquake, implying that this volcano is sufficiently sensitive to external events that are enough to trigger eruptions.
Possible Lithosphere Atmosphere Ionosphere Coupling before 19 September 2021 La Palma volcano eruption
Authors: Marchetti Dedalo , Zhang Hanshuo , Zhu Kaiguang , Zhima Zeren , Yan Rui , Shen Xuhui , Piscini Alessandro , Chen Wenqi , Cheng Yuqi , He Xiaodan , Wang Ting , Wen Jiami , Zhang Donghua , Zhang Yiqun
Published: February 2023

On 19 September 2021, La Palma Volcano started a VEI 3 eruption. Here we will illustrate an investigation for at least six months before the eruption with the aim of searching possible lithosphere atmosphere and ionosphere couplings.We identify and compare the anomalies from the seismic catalogue, the geomagnetic ground observatories, the atmospheric climatological datasets, TEC maps, CSES and Swarm satellites data with respect to the volcano location and the time cumulative trends of anomalies are analyzed.We identify a temporal migration of the seismicity from one year before the eruption at a depth of 40 km possibly associated with magma migration, firstly to a deep chamber (20-13km depth) and in the last 10 days in a shallower magma chamber. CSES-01 detects an increase in electron density at the same time as vertical ground magnetic field anomalies, very likely due to the magma uprising. A final increase of carbon monoxide 1.5 months before the eruption with unusually high values of TEC suggests the degassing of magma before the eruption associated with shallow seismicity that preceded the eruption by ten days. We identify possible different coupling mechanisms, e.g., chain of mechanical, thermal, chemical and electromagnetic phenomena, or pure electromagnetic coupling). These different lithosphere-atmosphere-ionosphere coupling mechanisms can coexist.Our results highlight the importance of integrating several observation platforms and datasets from the ground and space (earth observation satellites) to better understand the dynamics of the processes and associated natural hazards affecting our planet.
Using leaf chlorophyll observations to improve carbon cycle modelling at a temperate mixed forest
Authors: Thum Tea , Seppälä Outi , Croft Holly , Caldararu Silvia , Ojasalo Amanda , Rogers Cheryl , Staebler Ralf , Zaehle Sönke
Published: February 2023

Understanding the interactions between atmosphere and vegetation in changing climatic conditions is important so that we can predict the carbon sequestration potential of ecosystems. Helpful tools here are the terrestrial biosphere models (TBMs), since they include detailed ecophysiological process descriptions, e.g. the manifold interactions between the carbon and nitrogen cycles. However, the modelling of the nitrogen cycle poses challenges and having observational constraints on nitrogen cycle is crucial. Current remote sensing products offer estimates of leaf chlorophyll (Cab), that is related to the nitrogen cycle. In this study we want to assess how useful Cab observations are at site scale to constrain a TBM.
 
In this work we are studying a temperate mixed forest, Borden, located in Canada. We use a TBM QUantifying Interactions between terrestrial Nutrient Cycles, QUINCY, to model this site. From the site we have long-term (20 years) flux tower and LAI (from PAR measurements) observations together with leaf level observations of leaf chlorophyll (Cab), leaf nitrogen, and photochemical parameters of maximum carboxylation rate (Vcmax) and maximum potential electron transport rate (Jmax). 
 
The QUINCY model was predicting too late leaf senescence, which we tuned using the site level data. The amount of leaf nitrogen was originally quite successfully simulated by QUINCY, but the amount of simulated Cab was too low. Matching the simulated Cab values with the observations did not have a pronounced effect on the GPP. Additionally, the development of LAI and Cab were originally fully coupled in QUINCY, whereas the observations showed a delayed development of Cab compared to LAI. When we implemented this decoupling between LAI and Cab, an improvement of simulated GPP compared to the observations was found. Also then the simulated Vcmax and Jmax showed better correspondence to the observations. 
 
Assessment of the long-term behaviour of the model at the site showed that the model was able to capture the drought-induced drawdown of carbon fluxes taking place in 2007. The observations showed an increase in the component fluxes of carbon during the time period, but this was not replicated by the model. The start of season (SOS) and end of season (EOS) were estimated from both the simulated and observed GPP and LAI using a simple threshold method. The model was more successful in capturing the changes in the growing season metrics estimated by LAI than by GPP. The model was predicting too late onset of GPP in many years, but captured largely the interannual variation of SOS in observed GPP. 
 
This study paves the way for work using remotely sensed leaf chlorophyll in evaluation and improvement of the QUINCY model.
Pressure–temperature conditions and age of metamorphism in the Archean Acasta Gneiss Complex: constraints from phase equilibrium modelling and in situ garnet Lu-Hf geochronology
Authors: Kaempf Jonas , Johnson Tim , Clark Chris , Brown Michael , Rankenburg Kai
Published: February 2023

The Acasta Gneiss Complex (AGC) in northwestern Canada is home to the oldest known evolved (felsic) rocks on Earth, dating back to around 4.03 billion years (Ga). These rocks preserve evidence for multiple episodes of magmatism, metamorphism, and deformation, offering insights into the geological processes that shaped the Earth's crust throughout the Archean and late Hadean. However, the metamorphic pressure–temperature (P–T) conditions of this complex remain poorly constrained. In this study, we use phase equilibria modelling and in situ garnet Lu-Hf geochronology to analyse two garnet-bearing tonalitic gneisses in the AGC, providing the first quantitative P–T constraints for a late Paleoarchean tectono-metamorphic event in the AGC. Our results indicate metamorphic peak conditions of approximately 725-780°C and 4.5-6.2 kbar, with limited partial melting (<7 vol.%) of the felsic gneisses at these crustal levels. In situ Lu-Hf garnet geochronology suggests that this metamorphic event occurred between 3.3-3.2 Ga, consistent with previous findings of high-grade metamorphism at that time. Isotopic disturbance of garnet at approximately 1.9 Ga is interpreted to reflect partial resetting of the Lu-Hf systematics in response to fluid-present re-equilibration during the Paleoproterozoic Wopmay orogeny. Our study extends the limited dataset of published P–T data for Mesoarchean and older metamorphic rocks and shows that tonalitic gneisses in the AGC evolved along a high apparent thermal gradient of 125-150°C/kbar.
Deriving the hygroscopicity of ambient particles using low-cost optical particle counters
Authors: Huang Wei-Chieh , Hwang Wei-Chun , Hung Hui-Ming
Published: February 2023

The chemical composition and physical properties of aerosols significantly affect human health, cloud physics, and local climate. Hygroscopicity, a crucial physical property, represents the ability of aerosol to absorb moisture from the surrounding atmosphere and act as cloud condensation nuclei. In this study, we applied two home-built Air Quality Box (AQB) systems co-locating with Taiwan EPA Nanzi station (22°44’12” N, 120°19’42” E) in Kaohsiung, Taiwan, from 4 to 19 February 2021. AQB is composed of low-cost sensors to monitor the ambient gaseous pollutants (CO, CO2, NO, NO2, O3, SO2, and Non-Methane Hydrocarbons), aerosol particles (number size distribution between the diameter of 0.38-17 μm), and the meteorological parameters (T, RH, and P). As to PM (Particulate matter), EPA station monitors PM concentration at the dry state by controlling the measurement at less than 50% while the optical particle counter (OPC) in AQB reflects the ambient PM directly. The difference between the two values represents the amount of absorbed liquid water in the ambient condition. With the consideration of OPC sensitivity and aerosol hygroscopicity, OPC sensitivity and k-Köhler equation are applied to derive the hygroscopicity parameter (k) for PM2.5 (fine particles) and PM2.5-10 (coarse particles with a diameter in the range of 2.5 to 10 µm). In our preliminary results, OPC sensitivity is different between fine and coarse particles at RH<50%, suggesting the requirement of sensitivity adjustment for simple OPC at different particle ranges. The derived k ranges from 0.15 to 0.29, and 0.05 to 0.13 for fine and coarse particles, respectively. The results are consistent with those derived from collected samples analyzed using ion chromatography in our previous Kaohsiung winter campaign. The developed method provides a comprehensive way to determine the hygroscopicity of ambient aerosols, which can be helpful for atmospheric models to compare the results for further efficiency evaluation of aerosol acting as cloud condensation nuclei and radiation calculation. Furthermore, the application of this method for the low-cost sensors applied widely nearby EPA stations is under analysis to evaluate the performance of low-cost OPC sensors and to retrieve the enhanced temporal and spatial aerosol hygroscopicity.
Future runoff forecast in Hanjiang River Basin based on Wetspa model and CMIP6 model
Authors: Zhou Xi , Chen Wei , Liu Qingtao , Shen Hongxia , Cai Siyu , Lei Xiaohui
Published: February 2023

 In order to comprehensively consider the impact of human activities on runoff simulation and improve the accuracy of runoff simulation, so as to make a more accurate prediction of the future runoff of the Hanjiang River Basin, this study improved the reservoir module of the Wespa model, adding two parts: reservoir inflow data correction and water storage and outflow data calculation without measured data. Use the improved model to verify its applicability to the Hanjiang River Basin, then, choose the ones who has the most familiar trend with the historical data in the future climate model data (CMIP6). Put the selected data in the model to predict the runoff of Hanjiang River from 2021 to 2060. By analyzing the future runoff trend of Ankang, Huangjiagang and Huangzhuang in the Hanjiang River Basin from 2021 to 2060 and the changes of average runoff, seasonal runoff and monthly runoff compared with the historical period (1981-2020), the conclusions drawn are as follows: (1) The improved Wetspa model has good applicability in the Hanjiang River Basin; (2) The future runoff of Ankang section is decreasing, while that of Huangjiagang and Huangzhuang sections is increasing; (3) Compared with the reference period, the average runoff of the three sections in the future shows an increasing trend, which indicates that there will be flood risk in the future; (4) Compared with the reference period, the runoff proportion of the three sections will increase in spring and winter, and decrease in autumn. Attention should be paid to the risk of drought in autumn. In terms of months, the proportion of runoff from April to June increases, decreases from September to November, and increases and decreases in other months are uncertain.