bluuebunny/crossref_metadata_2025 huggingface dataset:
Predicting swelling pressure of bentonite and bentonite mixtures using various machine learning approaches
Authors: Shehab Muntasir , Taherdangkoo Reza , Butscher Christoph
Published: February 2023

Bentonite and bentonite mixtures are used as buffer material for deep geological radioactive waste repositories. The swelling behavior of bentonite is an important property influencing the long-term safety of the barrier system by its self-sealing effect. The proper determination of bentonite swelling pressure is vital to ensure that geological repositories remain intact. In this study, a total of 305 data samples on bentonite swelling pressure was collected from the literature. Corresponding soil properties were montmorillonite content, liquid limit, plastic limit, plasticity index, initial water content, and dry density. We employed various machine learning algorithms, namely feed-forward and cascade forward neural networks, regression tree, regression tree ensembles, Gaussian process regression, and support vector machines to determine the maximum swelling pressure of unsaturated bentonite and its mixtures. The cascade-forward neural network (CFNN) produced the best overall performance, i.e. the lowest modeling deviations from the experimental swelling pressure values. Furthermore, we present two simplified CFNN models that depend on two (montmorillonite content and initial dry density) and three (montmorillonite content, initial dry density, and plasticity index) variables to estimate bentonite swelling pressures. These simplified models can to be used as alternatives in instances of limited data availability.
England Peat Map: The challenges of using Earth observation data and machine learning approaches at the national scale
Authors: Hamer Alex , Dixon Sam , Kratz Christoph , Dornan Craig , Miller Chris , Prince Michael , Hart Charlie , Hunt Tom , Webb Andrew
Published: February 2023

The world’s peatlands are our largest terrestrial carbon store whilst also providing a sustainable source of drinking water, a haven for wildlife and storing a record of our past. The England Peat Map aims to provide baseline maps for the extent, depth, and condition of peaty soils in England by 2024. This will enable targeting of future restoration, support nature recovery, improve greenhouse emissions reporting and natural capital accounting.The maps will be created using a combination of multi-scale Earth observation imagery (satellite and airborne), existing and new ecological field survey data and machine/deep learning. Extent and depth mapping is implemented with random forest models and uses Sentinel satellite imagery and airborne LiDAR in combination with other ancillary datasets (e.g., geology and climate) for prediction. Assessment of peatland condition requires looking at these landscapes in different ways. Land cover mapping is used as a proxy for condition by targeting reflective classes for condition (e.g., Sphagnum, heather, and bare peat). Random forest and convolutional neural network (CNN) models are used in combination with Sentinel satellite imagery, aerial photography, and airborne LiDAR to produce national outputs. Mapping erosion/drainage features (grips, gullies and haggs) across the landscape is essential in understanding the underlying hydrological condition of the peatland and promising results have been achieved using CNNs with LiDAR and aerial photography. The final aspect of assessed condition is the movement of peat, also termed bog breathing, and is measured using Sentinel-1 Interferometric Synthetic Aperture Radar (InSAR). This opportunity is a result of novel in-situ peat movement cameras being installed across pilot sites to provide ground truth data.The final maps will be released free of charge under an open UK government license, allowing wider application and new opportunities for use compared with currently available datasets. For example, these baseline maps have the potential to contribute towards national peatland monitoring to address further decline of peatland habitats and target restoration interventions to achieve cost effective results. Several challenges have occurred during the initial phase of the project such as the difficulty in licensing suitable training data and in defining what we are mapping when features lack a globally agreed definition (e.g., surface features). The talk will discuss these challenges as well as the future direction of the project and how these challenges can be overcome.
The effect of water turbidity on the upper-ocean properties and dynamics in the Mediterranean and Black Seas
Authors: Karagiorgos John , Vervatis Vassilios , Sofianos Sarantis
Published: February 2023

Marine chlorophyll concentration has an impact on turbidity affecting the upper-ocean properties and regulating the air-sea fluxes. This work aims at assessing the effect of turbidity, as estimated via surface chlorophyll, on the heat content and dynamics of the Mediterranean and Black Seas. We performed twin-simulation experiments using a regional configuration of the NEMO v4.2 ocean model comparing: 1) a run with climatological chlorophyll satellite data to estimate turbidity and shortwave penetration in the water column, with 2) a reference run of fixed turbidity (i.e., chlorophyll concentration fixed at 0.05 mg/m3) corresponding to Yerlov type I clear waters. Interim results for long-term simulations (2008-2018) show that considering the effects of turbidity, as estimated from realistic surface chlorophyll concentrations, increases sea surface temperature, amplifies the seasonal cycle of temperature in the surface layer (0-20 m), and increases the annual heat loss in the Mediterranean Sea by about 1.5 W/m2. The latter is explained because the surface warming during summer is more intense than the cooling observed during winter, with differences between the two experiments reaching up to 2 °C in some regions. The increasing turbidity also affects the subsurface layers (20-200 m), with cooler temperatures throughout the year due to less solar radiation penetrating the water column. Ongoing work is currently being undertaken to estimate the indirect atmospheric feedback due to turbidity changes, using a fully-coupled ocean-atmosphere system (NEMO-WRF).
Control of Tropical Stability and Relative Humidity in Radiative-Convective Equilibrium Simulations
Authors: Wing Allison , Singh Martin
Published: February 2023

Radiative-convective equilibrium is the simplest possible way to phrase many questions about a deep-convecting atmosphere and is accessible by a wide range of model types. The radiative-convective equilibrium project (RCEMIP) provides a common configuration, but reveals a large spread in the simulated climate across models, including profiles of temperature and relative humidity. Here we use simple models and theory to understand the intermodel spread in CAPE, relative humidity, and their responses to warming.Across the RCEMIP ensemble, temperature profiles are systematically cooler than a moist adiabat, consistent with theory that they are set by dilute ascent. As horizontal grid spacing is reduced in models with explicit convection from 1 km to 200 m, CAPE and relative humidity increase. Across all models, CAPE increases with warming at a rate (14-19%/K) greater than that expected from the Clausius-Clapeyron relation. We find that there is higher CAPE (greater instability) in models that are on average moister in the mid-troposphere, which is consistent with the simple plume model of Romps (2016) in which both instability and relative humidity depend on entrainment and precipitation efficiency. The sign of the relationship suggests that differences in entrainment drive the intermodel spread. This relationship is true across both models with explicit and parameterized convection.To more explicitly evaluate the drivers of the intermodel spread, we use the Romps (2016) model to diagnose theory-implied values of entrainment and precipitation efficiency given the simulated values of CAPE and relative humidity. We then decompose the the variability across models in CAPE and relative humidity (and their responses to warming) into contributions from entrainment, precipitation efficiency, and the depth of the convecting layer. Targeted microphysics parameter perturbation experiments with an individual cloud-resolving model in which precipitation efficiency is varied and explicitly diagnosed provide proof of concept for this decomposition technique. 
Massive ozone production from South American wild fires observed during SOUTHTRAC
Authors: Hoor Peter , Kunkel Daniel , Hans-Christoph Lachnitt , Heiko Bozem , Vera Bense , Linda Smoydzin , Martin Riese , Andreas Zahn , Helmut Ziereis
Published: February 2023

During the SOUTHTRAC mission, which took place in September and November 2019, the Germanresearch aircraft HALO performed several cross sections from the equator to the southern tip ofsouth America. The flight legs were flown along the coast of Brazil at typical altitudes of 13-14 km.During the northbound flight on October, 7th 2019 massive enhancements of pollutants wereobserved at these altitudes. Notably, in-situ observations show continuously elevated CO valuesexceeding 200 ppbv over a flight distance of more than 1000 km. These massive enhancements wereaccompanied by strongly elevated NO and NOy as well as CO2 and could be attributed to the large firesin South America during this time. These fires occurred in conjunction with convection overArgentina and Brazil, which led to efficient vertical transport. Lagrangian and chemical model analysisconfirmed the potential impact of convection and biomass burning to the observed enhancements ofozone and pollutants.Comparing the tracer observations to previous flights in exactly the same region three weeks earlier,we could estimate the ozone production due to the biomass burning. Weestimate an ozone production in the polluted air masses of almost 30%of the observed ozone mixing ratio. Given the large extent of the polluted area over 15 degrees oflatitude this may have an impact on the local energy budget of the tropopause region.
Future changes of extreme precipitation and meteorological drought in Northern Italy
Authors: Guo Rui , Montanari Alberto
Published: February 2023

Simulation of daily rainfall for the region of Bologna produced by 13 up-to-date climate models for the period 1850–2100 are considered. In particular, model simulations are compared with the historical series of daily rainfall observed in Bologna in terms of annual, seasonal, extreme precipitation and meteorological drought for the period 1850–2014. Future changes of both precipitation and meteorological drought are analysed to assess future scenarios up to 2100 to derive information on the future development of critical events for water resources availability and flood risk. The results prove that rainfall statistics, including seasonal patterns and extremes, are fairly well simulated by models. For future projections, extreme rainfall shows a more significant change compared to the mean annual rainfall. In terms of meteorological droughts, we conclude that historical data analysis under the assumption of stationarity may depict a more critical future with respect to climate model simulations, therefore outlining important technical indications.
Global warming triggers the notable rise in water vapour: implications for global climate change
Authors: Patel Vikas Kumar , Kuttippurath Jayanarayanan
Published: February 2023

Among all greenhouse gases (GHGs), atmospheric water vapour is the most abundant and has huge influence on the Earth’s radiation budget, and plays decisive role in regional weather processes. Unlike other GHGs, which are controlled by emissions, atmospheric water vapour is influenced by the surface temperature. Here, we examine the long-term changes in global and regional water vapour using satellite and reanalysis datasets. The annual mean water vapour shows very high values in tropics and low values in the polar and high terrain regions. A clear seasonal cycle is observed in the water vapour, with high values in summer (25–65 kg/m2) and small values in winter (5–20 kg/m2), except in the tropics. The high values in summer is maily due to the enhanced evapotranpiration driven by surface air temperature, and water vapour transport by winds. There is a significant rise in annual mean global water vapour, driven by global warming, about 0.025–0.1 kg/m2/yr for the period 1980–2020. Furthermore, higher positive trends in water vapour is also observed in arid regions (Sahara, Arabian and Thar desert), Indian subcontinent and the Arctic. The higher values of water vapour trends in the Arctic is due to the significant rise in temperature there. Similarly, the increase in water vapour in desert regions is due to water vapour transport from nearby oceans. The associated radiative effects on short-wave at the surface varies from -5 to -70 W/m2 over the tropical radiosonde stations, and the smallest of about -5– -10 W/m2 in the polar regions. This study, therefore,  shows that there is significant rise in water vapour across the latitudes, which could further increase the global temperature through positive feedback mechamism and thus, change global and regional climate.Keywords: Water Vapour, Evapotranspiration, Global Warming, Arctic, Desert; Radiative Effects   
Temporal activity of subglacial channels around the grounding line of Roi Baudouin Ice Shelf, from ice-penetrating radar
Authors: Zhou Yan , Franke Steven , Kleiner Thomas , Drews Reinhard , Humbert Angelika , Jansen Daniela , Eisen Olaf
Published: February 2023

The existence of ice-shelf basal channels has a significant impact on both buttressing ability and basal melting of ice shelves in Antarctica. Although they can provide a unique perspective of processes for the mass transfer from grounded ice sheet to floating ice shelf, their origination and evolution are still not fully understood.Here we used airborne and ground-based radar to investigate the subglacial channel features at the grounding line (GL). We determined the geometry of five channels (two of which are characterized for the first time) in a set of flow-perpendicular radar profiles, also perpendicular to the channels. We found that the evolution from grounded subglacial channels to the ice-shelf basal channels mainly goes through three stages: (1) The grounded subglacial channels appear 4 to 5 km upstream of the GL and their incision into the ice sheet increases while approaching the GL; (2) as the subglacial channels extend into the grounding zone (1 to 2 km downstream of GL), their inner walls started melting, also they keep their roof-top features; (3) on the shelf interaction with the ocean, surface accumulation and ice dynamics further lead to flattening and widening, progressively turning them into generally known ice-shelf basal channels.Additionally to radar observations, we investigated the role of subglacial hydrology with two modelling approach (subglacial water flux with CUAS-MPI and water routing with CiDRE). A comparison shows that most channel locations in the radar profiles match with areas of higher subglacial water presence, consequently implying that subglacial water flux could mainly be responsible for maintaining the presence of subglacial channels.Based on the already earlier proposed relation that the presence of a sub-ice shelf basal channel is linked to a corresponding channel at the GL, we identify one now active channel at the GL to be related to one which was earlier until 59 years ago. This indicates that basal channels and consequently basal water flux across the GL can change at least on the scale of centuries. Our observed reactivation of a subglacial channel confirms the suitability of basal channels in ice shelves to be used as proxies of past subglacial hydrological activities and other potentially larger events.
Mineralogical and geochemical characteristics of lamproite minerals of the Murunsky massif.
Authors: Ashchepkov Igor , Vladykin Nikolai , Sotnikova Irina , Medvedev Nikolai , Karmanov Nikolai , Alymova Natalia
Published: February 2023

Minerals from leucite lamproites of the Murunsky alkaline massif (Vladykin, 2000; 2005; Vladykin, 2009) were analyzed by electron microscopy in the sections of 700 grains of minerals (IGM SB RAS) and LA ICP MS (IIC SB RAS) - 40 grains. Pyroxenes, amphiboles, various micas including varieties of the Ba type, leucites and nephelines, Ba and K feldspars, eudialyte, barite, stroztianite, ilmenites, Cr- spinelides, Ti magnetites, apatites, tourmaline, and various carbonates and sulfides: pyrrhotite, petlandite, chalcopyrite, murunite, smithsonite, galena. Pyroxenes are divided into 3 groups from diopsides to augites and aegirines, revealing a continuous series of compositions according to MgO (Fig. 1). Amphiboles K-richterites and arfversonites, and Ca-Fe ackermanites. Complete ranges from phlogopites to biotites have been established among micas. The proportion of Ba micas is significant. In the diagram  genetic digram (Minchell, 1995 )(Fig. 2) falls into the field of ailikites or orangeites,  and lamproites. Leucites and nephelines occurs  friquiently. Numerous apatites are characterized by Ca-Sr substitution and noticeable F contents (to 3%). K-type eudialytes and a mineral close to priderite were found. In the TRE diagrams (Fig.3), pyroxenes are characterized by La-enriched ~200-250 weakly inclined spectra of La/Ybn (2-3) that spread out in the HREE wing. Amphiboles of the K-Na-Ca are characterized show inclined spectra with Ho-Tm depression,  LILE peaks elevated Zr, Hf, Y and Ta-Nb minima. The more alkaline amphiboles are characterized by reduced REE concentrations, more  elevated Zr-Hf. Ultra-alkaline amphiboles (richterite and arfvedsonite) have higher REE contentswith characteristic U-shaped spectra, very high LILE contents high peaks of Sr, Zr, Hf. Phlogopites have oblique U-shaped spectra with a sharp peak Eu interference Ti. Very high LILE with a peak at Va, Sr, Y, Pb are typical.Low REE and especially LREE with a peak of Eu are characteristic of leucites. U, Sr, Pb peaks are also characteristic, and HFSE vary. The REE spectra of K-Ba feldspars are similar to those of phlogopite. High peaks of LILE, Sr, Pb, Y are expressed on spiderdiagramsJudging by the peculiarities of mineral trends, lamproites are the result of low degrees melting  under the influence of plume melts of a mantle deeply metasomatized by subduction processes. Pyroxenes are end–to-end minerals, at an early stage their compositions were controlled by fractionation of olivine and then saturated SiO2 silicates. Further fractionation led to enrichment with rare elements P, Sr, F. In amphiboles, the growth of REE was accompanied by the accumulation of Zr, Hf, while Nb, Ta were removed during the deposition of T-magnetite. Grant RBRF 19-05-00788.
Water quality dynamics of an extracted peatland and pond treatment
Authors: Dantas Mendes Lipe Renato , Renou-Wilson Florence
Published: February 2023

Peatlands comprise a significant share of the land surface in Ireland, i.e. 21%. Degradation of these ecosystems for horticultural industry purposes has exerted pressure on the water quality of surface waters. This occurs due to the removal of hydrophytic vegetation, drainage and exposure of the peat to aerobic conditions, in which the latter disturb the local water regime and accelerate decomposition processes. This subsequently results in significant leaching of carbon and nitrogen compounds such as dissolved organic carbon and ammonia. Despite the above, little study has focused on understanding the effects of peatland degradation on the waters leaving such catchments and therefore adequate mitigation measures.We hypothesize that the water quality of effluents from such extracted peatlands is highly dynamic, and these effluents are harmful to surface waters all year round. Here we compare the results with environmental thresholds and studies testing the effect of effluents in surface waters. We hypothesize that prolonging the hydraulic residence time of the effluents in situ does not suffice for treatment due to high proportion of soluble nutrients and lack of necessary biogeochemical conditions.The results presented here are based on long-term monitoring (c. 2 years to date) of an extracted degraded Irish raised bog (53°41'54.9"N 7°24'53.7"W). The site was drained for the extraction of horticultural peat. The drainage network allowed the water to flow into a pond for water treatment including particle sedimentation. Hereby, nutrient discharge from the site to surface waters downstream was expected to be minimised. A YSI EXO2 Multiparameter Sonde installed at the outlet and then at the inlet of the pond allowed continuous (up to 30-min interval) measurements of temperature, pH, conductivity, turbidity, fluorescent dissolved organic matter and ammonium concentration during most of the monitoring period. An area velocity flow meter paired with the Sonde allowed continuous (5-min interval) measurements of flow rate. In addition, a Teledyne ISCO Sampler 6712 installed at the pond outlet ensured time-proportional samplings during 11 storm events to date, i.e. when the pond water level exceeded a threshold. Finally, grab samplings have been periodically conducted at the pond inlet and outlet during the monitoring period. These samplings have been analysed for a series of water quality parameters including carbon, nitrogen, phosphorus and ionic compounds.Analyses of the data carried out to date corroborate the hypotheses. This includes acidic discharges, and variable and significant outflow concentrations of nutrients in different seasons, as well as minimal treatment in the pond. This subsequently highlights the need of proper mitigation measures in degraded peatland catchments in order to regulate the water quality of the effluents and ensure good ecological status of surface waters downstream.
Is priming influenced more by in situ or incubation temperatures? Evidence from a 1500 m elevation gradient in the Amazon
Authors: Martin Vivanco Angela Katherine , Sietiö Outi-Maaria , Seppänen Aino , Glaser Bruno , Uhlgren Oona , Mganga Kevin , Kalu Subin , Nottingham Andrew , Karhu Kristiina
Published: February 2023

Abstract
Growing attention has been paid to the significance of microbial metabolism for soil carbon (C) and nutrient cycle as well as their feedback effects on global warming. The estimated annual release of carbon dioxide from soil microbial respiration is 60 petagrams, and because aged native soil organic matter (SOM) has higher temperature sensitivity, the anticipated warming is expected to speed up its C release. Warming might increase litter and root exudate C inputs to hasten the decomposition of older SOM through priming effects. Microorganisms, however, have a rapid rate of growth and turnover and the new SOC formation from labile C inputs may be able to partly counteract the C losses through primed SOM decomposition. We are examining how temperature and the availability of C and nutrients affect the size and direction of priming effects. We conducted an incubation experiment on intact soil cores collected from altitudes ranging from 1500 to 3050 m a.s.l, and that were part of the Kosñipata gradient in the Peruvian Amazon. We incubated the soils for seven months, at two different temperatures to evaluate the impact of temperature, on the magnitude of priming effect caused by added 13C-labeled glucose, which was used as a model compound for labile root derived C inputs. At the end of the incubation, we determined the amount of 13C integrated into the microbial biomass and amino sugars, as well as the 13C remaining in bulk SOM.
Keywords 
Soil organic carbon, Priming effect, Soil respiration, Microbial residues, Elevational (altitudinal) gradient, Amazon
Hybrid modelling in hydrology by Neural Network-based prediction of conceptual model parameters
Authors: Acuna Eduardo , Ehret Uwe , Bäuerle Nicole , Loritz Ralf
Published: February 2023

In recent years data-driven techniques, specifically LSTMs, have outperformed conceptual hydrological models for rainfall-runoff prediction. However, even though great progress has been made to explain the internal functioning of the model ((Kratzert, et al., 2019); (Lees, et al., 2022)), their interpretation is still not as straightforward as conceptual models. Additionally, latent variables, different from the target quantity, need postprocessing methods to be extracted. One way to combine the flexibility of data-driven techniques with the interpretability of conceptual models is the use of hybrid models. In our contribution,  we will present results from applying a similar technique as (Kraft, Jung, Korner, & Reichstein, 2020) and (Feng, Liu, Lawson, & Shen, 2022), in which an artificial neural network dynamically calculates the parameters of the conceptual model. This approach increases the model flexibility, allows the inclusion of multiple information sources, and compensates for model uncertainty, while maintaining the straightforward interpretability of the conceptual part. In this contribution, we will look at the performance of the hybrid model, analyze the parameter variation over time, and present a technique to avoid parameter cross-compensation. ReferencesFeng, D., Liu, J., Lawson, K., & Shen, C. (2022). Differentiable, learnable, regionalized process-based models with multiphysical outputs can approach state-of-the-art hydrologic prediction accuracy. Water Resources Research. doi:https://doi.org/10.1029/2022WR032404Kraft, B., Jung, M., Korner, M., & Reichstein, M. (2020). HYBRID MODELING: FUSION OF A DEEP LEARNING APPROACH AND A PHYSICS-BASED MODEL FOR GLOBAL HYDROLOGICAL MODELING. The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 1537--1544. doi:https://doi.org/10.5194/isprs-archives-XLIII-B2-2020-1537-2020Kratzert, F., Herrnegger, M., Klotz, D., Hochreiter, S., & Klambauer, G. (2019). NeuralHydrology--Interpreting LSTMs in Hydrology. In W. Samek, G. Montavon, A. Vedaldi, L. Hansen, & K.-R. Müller, Explainable AI: Interpreting, Explaining and Visualizing Deep Learning (pp. 347--362). Springer.Lees, T., Reece, S., Kratzert, F., Klotz, D., Gauch, M., De Bruijn, J., . . . Dadson, S. (2022). Hydrological concept formation inside long short-term memory (LSTM) networks. Hydrology and Earth System Sciences, 3079-3101. doi:https://doi.org/10.5194/hess-26-3079-2022
Managing UK upland peat for greenhouse gas removal
Authors: Evans Martin , Ritson Jonny , Self Rebecca , Worrall Fred , Evans Chris , Lindsay Richard
Published: February 2023

Much of UK upland peat is in a drained and/or degraded state, meaning it is a net source of CO2 emissions to the atmosphere. Typical restoration methods, such as rewetting, can improve this, however most restoration projects only achieve a lowering or cessation of emissions with few achieving a net-negative carbon balance. In this new demonstrator project, Greenhouse Gas Reduction – Peat, we are trialling methods of supressing methane emissions as well increasing carbon sequestration so that carbon negative restoration projects can be achieved.The projects aims to accelerate the transition from degraded, burn-managed heather (Calluna vulgaris) bog to actively peat-forming bog, while minimising wildfire risk and CH4 emissions. We will present preliminary results and further plans for three techniques, trialled alongside typical gully blocking:1) Sphagnum planting: This ‘nature-based’ intervention will involve Sphagnum (a peat forming moss species) establishment using micropropagated assemblages of hummock-forming species which show the highest rates of C accumulation. During the first years of Sphagnum growth, CO2 sequestration may be in excess of long-term peat accumulation rates as a functional upper ‘acrotelm’ layer re-establishes. Sphagnum can also act as a CH4 biofilter, improving the net greenhouse gas balance.2) Heather mowing and biochar production: As an alternative to managed burning, we will harvest old heather biomass using low-ground pressure vehicles, followed by biochar production and re-application. Biomass removal will reduce wildfire risk, while controlled pyrolysis will avoid damage to Sphagnum/peat from burning, and enhance biomass conversion to biochar above that achieved in uncontrolled burns.3) Suppression of methane production: CaSO4  can supress methane formation by offering a more energetically favourable metabolic pathway to microbes, meaning sulphate reducing bacteria are more active than methanogenic bacteria. This essentially ‘nudges’ the bacterial population in a direction more favourable for greenhouse gas balances.
The concentration of neutral sugars in stemflow with respect to tree species and canopy phenophase
Authors: Levia Delphis F. , Chang Jeffrey L. , Epps, III Thomas H.
Published: February 2023

It is well known that stemflow contains soluble carbohydrates. While neutral sugars play an important role in tree metabolism, data on the concentrations of neutral sugars in stemflow are scant. Neutral sugar inputs via stemflow could influence soil solution chemistry and microbial activity in near-trunk soils. Accordingly, to fill the existing knowledge gap, this study quantifies stemflow neutral sugar concentrations with respect to tree species and phenophase. The concentrations of L-rhamnose, D-glucose, D-mannose, D-galactose, L-arabinose, and D-xylose in stemflow were determined using orbitrap liquid chromatography-mass spectrometry as a function of both tree species (Betula lenta L. [sweet birch], Fagus grandifolia Ehrh. [American beech], Liriodendron tulipifera L. [yellow poplar], and Pinus rigida Mill. [pitch pine]) and phenophase (emergence, leafed, senescence, leafless for deciduous species and emergence, leafed-spring/summer, senescence, leafed-winter for pine). Overall, the median concentrations for all sugars were higher for yellow poplar and pitch pine, and by phenophase, the leafless (or leafed-winter) phenophase had the highest (galactose, arabinose/xylose) or second highest (rhamnose, glucose, mannose) median concentrations for all sugars. We recommend the quantification of neutral sugar concentrations and fluxes in studies seeking a more comprehensive understanding of the physiological ecology of wooded ecosystems.________________Funding note: This research was supported by funds from the US National Science Foundation (Award No. GCR-CMMI-1934887).
Magma oceanography of the dense, ultrashort-period sub-Earth GJ 367b
Authors: Golabek Gregor , Lichtenberg Tim , Tackley Paul
Published: February 2023

The dawn of high-resolution observations with the James Webb Space Telescope will enable spatially resolved observations of ultrashort-period rocky exoplanets. Some of these planets orbit so closely to their star that they lack an atmosphere [1], which gives direct access to their surfaces and opens a window to infer their geodynamics [2]. The physical parameters of the ultrashort-period sub-Earth GJ 367b have been observationally constrained to a planetary radius of about 0.72 to 0.75 Earth-radii and a mass between 0.48 and 0.55 Earth-masses, implying a density of 6200 to 8500 kg/m3 [3, 4], which puts this planet in a Mercury-like interior regime with a thin mantle overlying a fractionally large core.The dayside temperature ranges between 1500 to 1800 K, thus suggesting the presence of a permanent magma ocean or dayside magma pond on the surface, induced by stellar irradiation. The large uncertainty on the age of the stellar system, between 30 Myr [4] and about 8 Gyr [3], however, introduce severe uncertainties related to the compositional and thermal evolution of the planetary mantle. In this study we perform global 2D spherical annulus StagYY simulations [5, 6] of solid state mantle convection and surface melting with the goal to constrain the geometric and compositional properties ofthe planet. Constraining the spatial dimensions of thermodynamic properties of partially molten, atmosphere-less planets like GJ 367b offers unique opportunities to constrain the compositional fractionation during magma ocean epochs and provides avenues to constrain the delivery and loss cycle of atmophile elements on strongly irradiated exoplanets.References:[1] L. Kreidberg and 18 co-authors. Absence of a thick atmosphere on the terrestrial exoplanet LHS 3844b. Nature, 573:87–90, August 2019.[2] T. G. Meier, D. J. Bower, T. Lichtenberg, P. J. Tackley, and B.-O. Demory. Hemispheric Tectonics on LHS 3844b. Astrophys. J. Lett., 908:L48, February 2021.[3] K.W.F. Lam and 78 co-authors. GJ 367b: A dense, ultrashort-period sub-earth planet transiting a nearby red dwarf star. Science, 374:1271–1275, 2021.[4] W. Brandner, P. Calissendorff, N. Frankel, and F. Cantalloube. High-contrast, high-angular resolution view of the GJ367 exoplanet system. Mon. Notices Royal Astron. Soc., 513:661–669, June 2022.[5] J. W. Hernlund and P. J. Tackley. Modeling mantle convection in the spherical annulus. Phys. Earth Planet. Int., 171:48–54, 2008.[6] P. J. Tackley. Modelling compressible mantle convection with large viscosity contrasts in a three-dimensional spherical shell using the yin-yang grid. Phys. Earth Planet. Int., 171:7–18, 2008.
Water chemical composition as indicator of geodynamic activity
Authors: Kazarian Armen , Kazarian Aik
Published: February 2023

WATER’S GEOCHEMICAL COMPOSITION AS INDICATOR OF GEODYNAMIC ACTIVITY A.Kazarian, H. Kazarian IGN AN NAN A detailed analysis of a long-term collection of hydro-geochemical data was carried out over a ten-year period. It revealed consistent iterations of signs of a process of earthquake preparation in this region. This preparation process has several distinct stages, which can be identified by noticeable changes in the geochemical composition of self-pouring well water. The earthquake preparation process is graphically visible and has a similar duration to the post-earthquake aftershock activity duration. The visualization of hydro-geochemical data from the pre- and post-earthquake periods for different (M> 6) earthquakes in this region shows a very similar pattern of behaviors and duration of behaviors for events of varying magnitudes and distances from the observation wells.Changes in the main fluctuation trend of the geochemical data for helium (He) and a decrease in the standard deviation of the series for other main components appear as earthquake precursors (Na, K, HCO3, SO4, Cl, Ca, F). The detectable duration of a main shock's preparation process is approximately a year. The detailed examination of the data time series reveals a strong correlation between the overall geodynamic activity of the region and the hydrogeochemical composition of the observed wells.The detailed analysis of earthquake activity in the region suggests a periodic nature of basic seismicity and its relationship with earthquake focal mechanisms. The obtained daily histograms for seismic activity in Armenia, Turkey, Greece, and Italy regions calculated by local time show cyclical activity patterns of 24 and 12 hours. This is consistent with variations in He and other important components in the well waters. The hypothesis and conclusion of this scientific research project are that in seismically active zones, the dynamics of hidden active tectonic processes can potentially be a priori diagnosed using this hydro-geochemical monitoring method.
Fastflood.org, an open-source super-fast flood model in the browser
Authors: van den Bout Bastian , Jetten Victor , van Westen Cees , Lombardo Luigi
Published: February 2023

Flood modelling, particularly for urban contexts, often suffers from the long computation time and detailed data requirements. Real-time forecasting requires fast, data-efficient tools. A recent break-through in rapid flood simulation has allowed us to develop www.fastflood.org, an open-source platform for near-instant fully spatial flood prediction. It uses the fast sweeping method for elevation model correction, flow accumulation, and estimation of steady-state discharge. Afterwards, a compensated partial steady state is estimated through catchment characteristics and a flood depth field is iteratively back-calculated. We will show that our method, in various real-world tests, achieves over 97% accuracy compared to traditional models in flood extent modelling, while obtaining a speed increase of over 1500 times. Together with recently published global datasets on elevation and land cover, the web-based tool allows for rapid setup and simulation of flood scenarios. Due to the speed of the method, editing of risk-reducing measures (reservoirs, barriers, channel alterations) can be carried out with direct feedback on the consequences for small to medium sized areas. Testing on flash and fluvial flood events show very good promise for early warning methods by linking the flood simulation technique with weather forecasts in real-time. Finally, by employing recent IT technologies such as web-assembly, the model can run completely on the user’s machine, allowing for a sustainable, free model. 
Automatic characterisation of Dansgaard-Oeschger events in palaeoclimate ice records
Authors: Barbosa Susana , Silva Maria Eduarda , Dias Nuno , Rousseau Denis-Didier
Published: February 2023

Greenland ice core records display abrupt transitions, designated as Dansgaard-Oeschger (DO) events, characterised by episodes of rapid warming (typically decades) followed by a slower cooling. The identification of abrupt transitions is hindered by the typical low resolution and small size of paleoclimate records, and their significant temporal variability. Furthermore, the amplitude and duration of the DO events varies substantially along the last glacial period, which further hinders the objective identification of abrupt transitions from ice core records Automatic, purely data-driven methods, have the potential to foster the identification of abrupt transitions in palaeoclimate time series in an objective way, complementing the traditional identification of transitions by visual inspection of the time series.In this study we apply an algorithmic time series method, the Matrix Profile approach, to the analysis of the NGRIP Greenland ice core record, focusing on:- the ability of the method to retrieve in an automatic way abrupt transitions, by comparing the anomalies identified by the matrix profile method with the expert-based identification of DO events;- the characterisation of DO events, by classifying DO events in terms of shape and identifying events with similar warming/cooling temporal patternThe results for the NGRIP time series show that the matrix profile approach struggles to retrieve all the abrupt transitions that are identified by experts as DO events, the main limitation arising from the diversity in length of DO events and the method’s dependence on fixed-size sub-sequences within the time series. However, the matrix profile method is able to characterise the similarity of shape patterns between DO events in an objective and consistent way.
NASA’s Carbon Monitoring System; lessons learned from 12 years of producing society-relevant, science-based, prototype Carbon-related products.
Authors: Jucks Ken
Published: February 2023

NASA’s Carbon Monitoring System (CMS) has a 12-year record of production of prototype data products from across Carbon Cycle Science that have potential usefulness for stakeholders outside the standard science community.   CMS originated from US Congressional direction through the budget process back in 2010 and remains currently.  CMS activities all include significant use of remote sensing data, as that is NASA’s strong suit.  We have been emphasizing increased engagement with stakeholders as CMS has progressed.  Prototype products exist currently related to GHG fluxes, terrestrial biomass, and ocean/coastal carbon.  Satellite sensors currently employed in CMS prototype products include OCO-2, OCO-3, S5P, GOSAT, GEDI, MODIS, and LandSat.  These various product development teams are coordinated through related working groups to help learn from the other projects, exchange ideas to improve outreach to stakeholders, and set potential direction for future CMS solicitations.  Many of the CMS products, that have existed for years and further developing, especially those related to GHG fluxes, have participants from numerous US agencies and have direct relationship to the coordination activities being discussed by many nations. 
Forced trends in the tropical Pacific and global tropical cyclones: An investigation using a statistical-dynamical downscaling model
Authors: Lee Chia-Ying , Camargo Suzana , Sobel Adam , Seager Richard , Fosu Boniface , Reed Kevin
Published: February 2023

The response of tropical cyclone activity to anthropogenic radiative forcing remains uncertain, with even the direction of the change uncertain in some respects (e.g., TC frequency), both globally and regionally. One important source of uncertainties is the Pacific zonal SST gradient. At the interannual time scale, this SST gradient, through the El Niño Southern Oscillation, is known to strongly influence global TC activity. Global climate models in CMIP5/6 generations project this SST gradient to weaken and lead to a more El Niño-like mean state in the future. Observations over the past several decades, however, show a strengthening of the SST gradient and thus a more La Niña-like mean state. While the observed strengthening of the SST gradient may be due to natural variability or merely an observational issue, some recent studies have marshalled evidence, backed up with modeling, to argue that the projected weakening is erroneous and a consequence of a common climatological cold tongue bias that has persisted in a few generations of global climate models. If the above argument is correct, at the transient forced response of Pacific SST over the upcoming decades will be towards a La Niña-like mean state, in contrast to the climate models. This means that the projected trends in TC activity from current state-of-the-art global climate models may be incorrect in some basins. In this presentation, we will report an initial investigation of the above problem using synthetic TCs from the Columbia tropical cyclone HAZard model (CHAZ) downscaled from CMIP6 models. Although all show El Niño-like forced responses, we will group the CMIP6 models/members based on the magnitudes of their climatological cold tongue biases, their historical trends of the zonal and meridional SST gradients, and the correlation between their trends and the observed one. For each stratified group, we will then evaluate SST gradient projections and how these projections affect the large-scale atmospheric and oceanic environment conditions that are important to TC activity and thus influence the forced trends in the CHAZ-CMIP6 downscaled TCs.  This work will inform on how much a potential model bias towards the wrong sign of the tropical Pacific zonal SST gradient change matters for projections of global TCs.
Harnessing new tools and satellite products to support landslide forecasting and capacity building over High Mountain Asia
Authors: Kirschbaum Dalia , Stanley Thomas , Amatya Pukar
Published: February 2023

The Hindu Kush-Himalaya (HKH) is one of the greatest geologically fragile young mountain systems in the world and are highly vulnerable to landslides. Extreme rainfall, seismic activity and human interventions result in landslides and related hazards that cause severe economic losses each year and can cause hundreds of fatalities annually. Effective response, mitigation and planning for landslide impacts is often challenging due to limited information on historical landslide behavior, land surface characteristics, impacts, and triggering processes. High resolution and publicly available satellite data, Earth system models, and machine learning approaches can provide enhanced understanding of where and when landslides impact  the HKH and importantly how these patterns may change in the future. Several efforts led by NASA, including the High Mountain Asia program and the SERVIR program have enabled new datasets, models, and capabilities to support both scientific advancement and capacity building activities within this region in terms of cascading hazards and their impacts. This work leverages a global and regional modeling approach called the Landslide Hazard Assessment for Situational Awareness (LHASA) as well as a machine-learning driven algorithm for identifying landslides called the Semi-Automatic Landslide Detection (SALaD) to bridge spatial and temporal scales for improved situational awareness of landslide hazards. Building upon several downscaled, regionally focused near real-time and forecasted precipitation information, this work also presents an initial assessment of changing patterns of potential landslide hazard across this region considering the past several decades and looking to the end of the 21st century. Through harnessing open source tools and data products available for HKH, this work demonstrates the potential for improving situational awareness and characterization of landslide hazards within the regional context at daily to decadal scales. Working closely with regional stakeholders, these capabilities will inform emergency response and planning on the ground as well as provide context for possible future mitigation needs.
Fluid diffusion and pore-pressure distribution in microcracked rocks
Authors: lin gang , Chapman Samuel , Fortin Jérôme , Schubnel Alexandre
Published: February 2023

Pore pressure has a major influence on the effective stress and thus on the mechanical behaviour and the physical (elastic and transport) properties of microcracked rocks. In the field, in-situ measurements of pore-pressure is difficult outside of local measurements around boreholes. Yet, fluid migration is observed ubiquitously in the continental crust, whether in fault zones or in volcanic geothermal areas. In particular, pore pressure perturbations change the effective stress, which may lead to microseismic activity. This may also occur in conventional reservoirs, the storage of CO2 or deep geothermal energy extraction. In this study, we focus -in the laboratory- on the hydro-mechanical behavior of thermally treated Westerly granite and naturally microcracked Etna basalt samples (40 mm in diameter and 80 mm in length). The goal is to determine the pore pressure distribution and diffusion laws under different pore pressure gradients. First, classical (constant flow method) permeability measurements under small pore pressure gradient (1 MPa over the length of the sample) were carried out as a function of increasing confining pressures Pc (up to 70 MPa). The results show that permeability of samples varies exponentially with effective pressure, which is expected for cracks-porous rocks. The pressure sensitivity factor for permeability was then deduced to be of the order of 0.011~0.057 MPa-1. In a second step, permeability was measured at high (70 MPa) confining pressure, under large pore-pressure gradients (up to 60 MPa). During this part of the experiments, pore pressure was measured along the sample using newly developed fluid pressure sensors (with an absolute accuracy of +/-1MPa). Under small pore pressure gradient (2.5 MPa), our results show that the pore pressure varies linearly over the length of the sample, as expected from Darcy’s law and a constant permeability. However, with increasing pore pressure gradient (up to 60 MPa), the linearity is lost, as the permeability can no longer be assumed constant along the sample. To interpret our results, we solved the diffusion equation, assuming that permeability varies exponentially with effective pressure. For steady state flow conditions, our observations of the pore pressure distribution in the samples are consistent with the theoretical predictions. In particular, we show that the shape of the pore-pressure distribution at steady-sate does not depend on permeability itself, but rather on the permeability pressure sensitivity factor: the larger the latter, the more non-linear the pore pressure in the samples.