bluuebunny/crossref_metadata_2025 huggingface dataset:
Plio-/Pleistocene landscape evolution in the Eastern Alps: new insights from cosmogenic nuclide dating
Authors: Gradwohl Gerit , Stüwe Kurt , Robl Jörg , Plan Lukas , Fabel Derek , Stuart Finlay , Liebl Moritz , Di Nicola Luigia
Published: March 2022

The Eastern Alps hold an abundance of landscapes with noticeably low topographic gradients at higher elevations above much steeper slopes. Many of these elevated low-relief landscapes (ELRL) are organized in distinct surface levels. Sub-horizontal cave systems can often be found at similar elevations. Utilizing spatial statistics of these ELRL and over 15000 caves, we show that the formation of both the surface and sub-surface landscapes is connected and can help deciphering the landscape evolution of the Eastern Alps from the Late Neogene until today. New cosmogenic nuclide data (10Be, 21Ne, 26Al) of allogenic quartzous sediments from caves and surfaces of distinct elevation levels in the Eastern Alps are used to quantify the incision and ultimately surface uplift history. Burial ages of cave sediments scatter between 0.5 and over 5 Ma. The preliminary data indicate a mean surface uplift of some 0.15 – 0.25 mm/year for much of the Pliocene. We also show that most ELRL in the Eastern Alps can be interpreted in terms of pre-Pleistocene relict landscapes, especially in the only minorly glaciated eastern part.  However, the data also show some impact of the Pleistocene glacial cycles on the ELRL and the mobilization of sediments associated with them.
Analyzing Ca-41 sample at E-16 abundance level with cold atom trap techniques
Authors: Xia Tian , Xia Tong-Yan , Sun Wei-Wei , Zhu Hui-Min , Jiang Wei , Lu Zheng-Tian
Published: March 2022

On earth, Calcium-41 is produced as a cosmogenic isotope via neutron capture process, leaving a natural isotopic abundance of 10-15 on earth surface. Calcium is also of vital importance for the metabolism of biological organisms. Consequently, analysis of the long lived radioactive isotope Calcium-41 is of great importance in geoscience, archeology and life sciences. The half-life of Calcium-41 is 1.03 x 105 years. It is a good candidate in dating rock and bone samples ranging from 50,000 to 1,000,000 years old.

The available techniques for trace analysis of Calcium-41 include accelerator mass spectrometry (AMS) and resonance ionization mass spectroscopy (RIMS). The detection limit of RIMS is on the level of 10-11 due to the interference of Potassium-41, which is difficult to remove from the sample. The analysis with high-energy AMS is more expensive than the table top apparatus, and it also faces similar problem as RIMS method.

We develop an atom trap trace analysis(ATTA) apparatus for Calcium-41 analysis to the sensitivity of 10-16 abundance level by one day of single atom counting. ATTA uses laser tuned at the resonant wavelength for a specific element and isotope to slow down and capture single atom by fluorescence radiation. It has a very high selectivity of element and isotope, which is more advantageous than AMS and RIMS to avoid isobar interference. ATTA has been used in analysis of Krypton-81, Argon-39 dating of the hydrological samples. This work on high sensitivity Calcium-41 analysis is very promising in dating the geochemical sample to determine the exposure ages of rocks or in cosmochemistry for investigations on terrestrial ages.
Numerical simulation of air entrainment by three dimensional pyroclastic surge flow model
Authors: Tonoyama Shungo , Nakamura Takashi
Published: March 2022

Pyroclastic currents, which composed by ash particles and small pyroclasts, is one of destructive ejecta produced during volcanic eruptions. The behavior of this hazardous fluid is still not revealed yet. In particular, dilute fluids called pyroclastic surge can expand and diffuse by entrainment of ambient air and has a possibility of danger. Due to lack of understanding about pyroclastic surge, current disaster prevention measures are inadequate in estimating the run-out distance and range. In recent years, several experiments on the pyroclastic flows have been conducted; however, to reproduce both high temperature and high velocity is quite difficult. Therefore, the numerical calculation is considered as the powerful tool to analyze their flow structures. Here, we applied the numerical model of a pyroclastic surge to the experimental investigation at Smithsonian Institute in order to examine the air entrainment. Our model is based on solving Navier-Stokes equation by finite-difference scheme, CIP-CUP method, and Smagorinsky model applied to turbulent mixing. In this study, pyroclastic surge is treated as a dilute turbulent suspension, and gas and particles are assumed to be well-mixed or have certain settlement velocity. We applied the 2D and 3D model to experiments and investigated the effects of turbulence and settlement. As a result of a series of simulations, we can reproduce the generation of head and wake and it has a strong relationship with mesh size. The large mesh cannot capture the wake at rear of head. Furthermore, the temperature change process by turbulent mixing is confirmed. The experimental data at PELE (the pyroclastic flow Eruption Large-scale Experiment) is also compared and discussed about the change in flow height.
Studying the dynamic of a high Alpine catchment through the scope of multiple natural tracers
Authors: Ceperley Natalie , Michelon Anthony , Beria Harsh , Vennemann Torsten , Schaefli Bettina
Published: March 2022

 

The characterization of surface-subsurface water exchange in snow-dominated catchments is key to predicting streamflow generation under a warming climate. Stable isotopes of water (SIW) as flow path tracers have become very popular in such environments despite sampling challenges related to access in harsh winter conditions and the fact that such analyses remain costly compared to other natural tracers such as electric conductivity and water temperature. However, SIW alone capitalize on the well-known difference of the SIW ratios from water originating as summer rainfall versus winter snowfall, which propagate into the water stored in the subsurface and into streamflow.

In this presentation, we report our conclusions on the potential of year-round SIW samples to characterize the hydrological processes in the high elevation Vallon de Nant catchment (13.4 km²), located in the Western Swiss Alps. SIW ratios are shown to be particularly useful to characterize the interplay of direct (surface) and subsurface snowmelt input to the stream network during winter and early snow melt periods. We furthermore show that subsurface flow plays a critical role during all melt periods and our tracer data points towards the presence of snowmelt even during winter base flow.

We furthermore demonstrate the added value of soil and water temperature measurements to interpret SIW ratios in snow-dominated environments, by giving additional information on snow-free periods, on flow path depths and on temporary fast connections between surface and subsurface flow.
Coronal dimmings as indicators of the CME  evolution close to the Sun
Authors: Chikunova Galina , Podladchikova Tatiana , Dissauer Karin , Veronig Astrid
Published: March 2022

Coronal dimmings are regions in the solar corona that represent a sudden decrease of the coronal EUV and SXR emission, which is interpreted as a density depletion caused by the evacuation of plasma due to the CME eruption. Distinct relations have been established between coronal dimming parameters (intensity, area, magnetic flux) and key characteristics (mass, speed) of the associated CMEs by combining coronal and coronagraphic observations from different viewpoints in the heliosphere   (Dissauer et al. 2019, Chikunova et al. 2020).

In this contribution, we study whether coronal dimmings can be used to indicate possible deflections of CMEs close to the Sun and to identify their propagation direction. We present a set of detailed case studies where, by using simultaneous observations from the SDO and STEREO satellites, we track both the evolution of the coronal dimmings and the CME properties with respect to their directions. Our findings suggest that the direction of growth of the coronal dimming region and the evolution of the dimming intensity are related to the initial direction of the CME and also reflect various changes in its evolution, indicating deflection and/or interaction with surrounding active regions. These findings are important in better constraining CME evolution and direction close to the Sun and its further connection toward interplanetary space.
Impact of wind speed variability on the surface energy balance and boundary-layer stability in central Alaska
Authors: Maillard Julia , Ravetta François , Raut Jean-Christophe , Fochesatto Gilberto , Law Kathy
Published: March 2022

The pre-ALPACA (Alaskan Layered Pollution And Chemical Analysis) 2019 winter campaign took place in Fairbanks, Alaska, in November—December 2019. One objective of the campaign was to study the life-cycle of surface-based temperature inversions and the associated surface energy budget changes. Several instruments, including a 4-component radiometer and sonic anemometer were deployed in the open, snow-covered UAF Campus Agricultural Field. The surface energy budget at the UAF field exhibited two preferential modes. In the first mode, turbulent sensible heat and net longwave fluxes were close to 0 W m−2 , linked to the presence of clouds and generally low winds. In the second, the net longwave flux was ≈ -50 W m−2 and the turbulent sensible heat flux was ≈ 15 W m−2 , linked to clear skies and the presence of a local flow. The development of surface temperature inversions at the UAF field was hindered compared to other locations in Fairbanks because the flow sustained vertical mixing. Indeed, the wind speed at 2 m was around 5 m s-1, above the estimated critical wind speed threshold for sustainable turbulence in the MWST (Minimum Wind speed for Sustainable Turbulence) framework. Despite the clear skies, the local flow maintained a weakly stable state of the boundary layer.

These results suggest there is significant variability of Arctic boundary-layer stability due to variations in the near surface wind speed, even in anticyclonic, clear-sky conditions. Accurate representation of the stable boundary-layer by meso-scale models therefore requires that they reproduce the wind-driven transition between weakly stable and strongly stable states correctly. The impact of parameters such as stability functions and roughness length on the modelled transition thus represents an important follow-up question to this study.
Ensemble based data assimilation of bio-geochemical profile data in the Baltic Sea with a Nemo-ERGOM model system
Authors: Düsterhöft-Wriggers Wibke , Spruch Lena , Lindenthal Anja , Li Xin , Lorkowski Ina , Team Balmfc
Published: March 2022

The presentation focuses on two key points in bio-geochemical ensemble based data assimilation: the ensemble generation methods as well as the impact of the data assimilation on various bio-geochemical processes. We conduct the data assimilation experiments from October 2014. These are preparations for a future reanalysis product provided by the Baltic Monitoring and Forecasting Centre (BAL-MFC), which will cover the years 1993 – 2021. The Local Error Subspace Kalman Transform Filter (LESKTF) algorithm in the Parallel Data Assimilation Framework PDAF (http://pdaf.awi.de) is applied for data assimilation of profile data from the SHARK database on a daily basis. After the daily analysis is performed, the mean of the ensemble members is used in the Nemo-ERGOM model system. This method is used operationally by the BAL-MFC.

Effects of the number of ensembles, transformations, generation techniques and deflation of the ensemble are explored and verified in our ensemble generation studies. Rank histograms, skewness and kurtosis of the ensembles before and after assimilation are computed.

The influences of dissolved oxygen profile data assimilation on the nutrients in deep layers are studied and compared with the integral influences of univariate data assimilation of dissolved oxygen, nitrate, phosphate and ammonium on the same variables. Validation results of the univariate data assimilation scheme are presented and discussed in regards to quality enhancement for the future reanalysis product.
The evolution of UK sea-level projections
Authors: Weeks Jennifer H. , Harrison Benjamin J. , Palmer Matthew D.
Published: March 2022

The methods used to generate global to local sea-level projections have evolved significantly since the publication of the first set of UK national sea-level projections in 2009 (UKCP09; Lowe et al, 2009), including improved process understanding, ice-sheet modelling advances, the use of emulators and development of high-end scenarios. The UK Climate Projections in 2018 (UKCP18) presented local mean sea-level projections for the UK coastline for the 21st century based on CMIP5 models, with an emulator-based methodology to provide traceable extended projections to 2300 (Palmer et al, 2018). First, we present the evolution of UK sea-level projections since UKCP09 and discuss how these projections have been used by UK stakeholders. Second, we compare UKCP18 global and local sea-level projections with those recently presented in the IPCC Sixth Assessment Report (AR6). We find that although the likely range projections (i.e the characterisation of the central two-thirds of the distribution) are broadly similar, larger AR6 contributions from oceanographic processes and the Antarctic ice sheet give rise to discrepancies at selected tide gauge locations of up to 30%. In AR6, high-end scenarios for sea-level rise were presented as low-likelihood high-impact storylines. These offer some comparison with the high-end H++ range presented at 2095 for UKCP09, showing reasonable agreement for London. Future UK sea-level projections would benefit from updated scenarios for high-end sea-level change which extend beyond 2100 as well as an improved understanding of observed sea-level change drivers. This will enhance the usability of these local sea-level projections by UK stakeholder groups and coastal decision-makers.
Clarifying the relation between chromospheric emissions and photospheric magnetic fields using AIA 1600 Å and HMI data
Authors: Tähtinen Ismo , Virtanen Ilpo , Pevtsov Alexei , Mursula Kalevi
Published: March 2022

Intense photospheric magnetic fields manifest as enhanced emission in several spectral lines and parts of the continuum. Here we aim to improve the understanding of the relation between magnetic fields and radiative structures by using the seeing-free observations of the Atmospheric Imaging Assembly (AIA) and the Helioseismic Magnetic Imager (HMI), both on-board Solar Dynamics Observatory (SDO). We use AIA 1600 Å band, which captures the far-ultraviolet continuum emission originating from the temperature minimum of the solar chromosphere.

We developed a novel, objective method to define thresholds separating the brightest AIA 1600 Å pixels ("bright pixels") and the least bright pixels ("dark pixels") from the AIA 1600 Å brightness distribution. According to the method bright pixels are pixels whose standardized contrast (ratio of brightness to the center-to-limb variation) exceeds the level of I = 1.93. This threshold maximizes the average size of bright clusters (4-connected regions of bright pixels). Dark pixels are pixels whose standardized contrast is below I = 0.5. This corresponds to a threshold below which there are practically no pixels on quiet days. Comparing the AIA 1600 Å intensity and HMI magnetic field observations, we found that the AIA 1600 Å dark pixels correspond to the strongest magnetic field (B > 1325 G) pixels. These pixels are typically within sunspots. On the other hand, we found the AIA bright pixels correspond to moderate (55 G < B < 475 G) magnetic field intensity pixels of HMI.

We found that the percentage of AIA bright pixels on the solar surface almost entirely explains the observed variability of the total AIA 1600 Å emission, even in the presence of large sunspot groups. We developed a multi-linear regression model, which reliably predicts the magnitude of the disk-averaged unsigned magnetic field using the measured percentages of bright and dark pixels. We found that the large bright clusters have a constant mean unsigned magnetic field, similarly as earlier found for, e.g., Ca II K plages. However, the magnetic field strength of bright clusters is 246.5 ± 0.1 G, which is roughly 100 G larger than found earlier for Ca II K plages.
Elucidating source areas of in-stream DOC by characterizing stream-groundwater exchange in a low mountain forested headwater catchment
Authors: Hopp Luisa , Kehr Jana , Blaurock Katharina
Published: March 2022

Export of carbon from terrestrial catchments remains a poorly understood flux within the global carbon budget. In order to better understand the release and in-stream transport of dissolved organic carbon (DOC) in a small forested headwater catchment within the Bavarian Forest National Park (Germany), we characterized the stream-groundwater exchange along the headwater stream. We divided a 3000 m long stretch of the headwater stream into three topographically delineated sections that consisted of a steep upstream section (length 620m, elevations 888-967 m a.s.l.), a transition section (length 770 m, elevations 805-855 m a.s.l.) and a flat and wide downstream section (length 1330 m, elevations 770-805 m a.s.l., outlet of headwater catchment). Using sequential tracer injections of known masses of sodium chloride, we determined stream discharge and lateral exchange fluxes between stream and the surrounding riparian zone in the three stream sections and evaluated the effects of the resulting hydrologic turnover on stream water composition. We also compared the calculated lateral exchange fluxes with previously measured longitudinal profiles of Radon activities that can be used to locate groundwater inflow points. Discharge increased over the investigated 3000 m stretch in downstream direction, as expected, although the transition section did not show any change in discharge. The analysis of recovered tracer masses revealed that in the steep upstream section, the exchange fluxes consisted mainly of inflow of water into the stream. The transition section was characterized by an absence of exchange fluxes. In the downstream section, however, large inflows were offset by slightly lower outflows, resulting in a very pronounced exchange between stream water and riparian zone groundwater in this flat valley bottom. The spatial pattern of exchange fluxes was supported by the longitudinal Radon profiles, which pointed to a marked groundwater inflow in the downstream section. Our results suggest that the dominant source area of in-stream DOC at the outlet of our headwater catchment is the flat and wide valley bottom in the downstream section as most of the DOC released into the stream along the steep upstream section will be removed from the stream during the passage through the downstream section.
Novel Cold Season Temperature Field Reconstructions for the Northern Midlatitudes from Phenological Data
Authors: Burgdorf Angela-Maria , Brönnimann Stefan , Reichen Lukas , Franke Jörg , Hand Ralf , Valler Veronika , Samakinwa Eric , Burgnara Yuri , Rutishauser This
Published: March 2022

Annual-to-decadal variability in northern midlatitude temperature is predominantly dominated by the cold season. However, climate field reconstructions, which are essential for understanding the underlying mechanisms, are often based on tree rings. These mainly represent the growing season and allow limited insight on cold season effects. Plant and ice phenology data, on the other hand, are a rich source of cold season information that remains largely overlooked in climate reconstructions to date and could help to fill the seasonal gap. Here, we present Northern Hemispheric temperature field reconstructions for the extended cold season (October-to-May average) for 1701-1905 based entirely on phenological data. Time series of freezing and thawing dates of rivers together with a few early-spring plant observations covering a large area of the northern midlatitudes are used in a simple data assimilation framework.
The reconstructions allow a 320-yr perspective of climate variability and change of boreal cold season climate and unveil that the temperature of the northern midlatitude land areas exceeded the variability range of the 18th and 19th centuries by the 1940s, to which recent warming has added another 1.5 °C. We also find 5-10 year long sequences of cold northern midlatitude winters. The most prominent example lasted from 1808/9 to 1815/6. The conspicuously cooling during that period is associated with two volcanic eruptions (1808/9 and 1815), which caused cooling as a direct effect. The years between the eruptions are characterized by weak southwesterly atmospheric flow over the Atlantic-European sector in early winter. This lead to low Eurasian temperatures, which persisted into spring while the flow pattern did not. Twentieth century data and model simulations confirm this persistence and point to increased snow cover as a cause. This is consistent with independent information on Eurasian snow in the early 19th century.
A turbulence closure scheme in the wave boundary layer and its application in a coupled model
Authors: Wu Lichuan , Qiao Fangli
Published: March 2022

Air-sea interactions are important for weather and climate predictions since they control the momentum and energy transfer between the atmosphere and the ocean. In current models, the momentum flux in the atmospheric boundary layer is estimated by turbulence closure models which were developed heavily based on measurements over land. However, those turbulence closure models often fail to capture the momentum flux and wind profile in the marine atmospheric boundary layer due to wave impacts. In this study, we proposed a new turbulence closure model to estimate the wind stress in the wave boundary layer from viscous stress, shear-induced turbulent stress, wind-sea induced stress, and swell-induced upward stress, separately. The misalignment between the wind stress and wind is also considered in the model. Single-column simulations indicate that 1) the swell-induced upward momentum flux increases the surface wind and changes the wind direction, 2) the misalignment between the upward momentum flux and wind has a more significant impact on the wind profile than that from the downward momentum flux, and 3) the impact of swell-induced upward momentum flux decreases with atmospheric convection. The proposed closure scheme was implemented into an atmosphere-wave coupled model. A month-long simulation over the ocean off California shows that the surface wind can be altered up to 5% by ocean surface gravity waves.
Carbon cycle responses in the Amazon region to large scale climatic modes of variability
Authors: Mastropierro Matteo , Zanchettin Davide
Published: March 2022

Drying is expected in many regions of the world by the end of the 21st century under increased greenhouse gas emissions. Climate projections robustly indicate that the tropical Amazon region is particularly sensitive to future climate change. On the one hand, an increased occurrence of heat and aridity events may largely impact the main vegetation processes in the coming decades. On the other hand, these extreme heat and drought events interfere with and are mediated by slowly changing climatic conditions, primarily those associated with raising CO2 concentrations, that could alleviate negative impacts of global warming on regional ecosystems and carbon stocks. In this context, the relationship between extreme climatological events and climatic modes of variability plays a critical role. Throughout the tropics, El Niño Southern Oscillation (ENSO) is the predominant mode regulating vegetation's carbon dynamics, with significant reductions in terrestrial carbon uptake being related to increased temperatures and decreased precipitation associated with its Niño positive phase. However, its future amplitude and contribution to extreme climatological events and consequently to tropical atmosphere-carbon fluxes is still debated in the scientific community. At the same time, the importance of other modes of variability on the terrestrial vegetation dynamics and carbon sinks remains unexplored. On this premise, this research aims at filling this gap of knowledge by exploiting the results of several Earth System Models (ESM) simulations contributing to CMIP6 for three future scenarios: ssp585, ssp370, and ssp534-over. Given its importance for the balance of the global carbon cycle, the focus of the analysis is on the Amazon region. In this contribution, we will illustrate multi-model results concerning the projected future behavior of selected climatic modes of variability that are known to affect the Amazon region. A special focus will be on climate modes' characteristic timescales and amplitudes since these could effectively enhance or damp climatological extremes.
The coldest days of MOSAiC – an LES study 
Authors: van der Linden Steven , Ansorge Cedrick
Published: March 2022

The polar-night stable boundary layer, observed during MOSAiC, gives rise to extreme stabilities not found in typical mid-latitude SBLs. In a steady or near-steady synoptic environment, the boundary layer even attains a quasi-steady state for several hours, i.e., boundary-layer processes and profiles are equilibrated.

Such lab-like conditions of extreme stability remain a major challenge for turbulence modelling across scales. Previously, we have demonstrated that such situations can be qualitatively modelled by carefully-designed large-eddy simulations, using wintertime observations from Dome C, Antarctica (Van der Linden et al., 2020: J. Atmos. Sci., 77, 3343–3360). However, a quantitative comparison remained elusive due to a lack of turbulent flux observations at Dome C.

The high-frequency observations of wind, temperature, radiation and turbulent fluxes during the MOSAiC-campaign do allow us to quantitatively disentangle different mixing processes facilitating a one-to-one comparison between observation and simulation. Here, we will show the results of our simulations and discuss the specific challenges of performing large-eddy simulations of such harsh, but fascinating conditions.

Our results show that atmospheric radiation, which is usually neglected in large-eddy simulations of very stable cases, is a key thermal process in the evolution of the boundary layer due to the large thermal inversion near the surface. Radiative exchanges result in a deeper boundary-layer, which is in line with the observed boundary-layer height, as compared to the simulations without radiative exchanges. Although a larger boundary-layer depth is obtained, discrepancies between the observed more exponentially-shaped temperature profile and the simulated temperature profile still persist.

This is suspected to be caused by a wrong magnitude of the turbulent mixing near the surface, related to the interplay of roughness lengths, Monin–Obukhov similarity theory and the extreme surface-layer stratification. Initial tests, however, remain inconclusive on this complex interplay.
Ultrasonic imaging of analogue scale models
Authors: Smits Jasper , Beekman Fred , Vasconcelos Ivan , Willingshofer Ernst , Van Wijk Kasper , Matenco Liviu
Published: March 2022

Since the 19th century pioneering work of Sir James Hall, physical analogue modelling has been proven a valuable method for the study of geological phenomena and has significantly contributed to understanding fundamental mechanisms of crust and lithosphere deformation. Traditionally, in such analogue scale models, structural deformation is monitored and quantified using top-view images or cross-sections, where the latter allow for portraying the final state of internal deformation of the model in great detail. Monitoring the evolution of internal deformation while the experiment is running is however a major challenge, and currently is possible only with X-ray scanning using medical-type CT scanners. These, however, put stringent limitations on size of the model and, thus, the possible geometric configurations related to different modelling setups.

To tackle these limitations, we are developing a novel method to image the evolving interior of analogue scale models using ultrasonic techniques. Similar to reflection seismology used in field studies, the internal structure of the analogue model can be imaged using sound waves. We employ a completely non-contact and non-invasive method, utilizing a laser Doppler vibrometer to detect the arrivals of seismic body waves at the model surface. A laser pulse from a powerful pulsed laser acts as a point source and is used to introduce acoustic waves in the model. By moving the detector and source, acoustic data is recorded for a number of source-recorder combinations, allowing the reconstruction of the internal layering and structure along cross sections, as will be illustrated by the results of several tests with analogue models and other samples. By developing this technique, we provide novel tools to characterize the acoustic behaviour of subsurface structures under well-controlled laboratory conditions with the aim of improving our understanding of waveforms and wave propagation in analogue models and earth materials in general.
Spatiotemporal Patterns of Drought and Multi-scale Linkages of Seasonal Drought to Climate Indices: A Case Study in the Huaihe River Basin, China
Authors: Li Xin , Fang Guohua , Zhang Zhenyu , Arnault Joël , Wen Xin , Kunstmann Harald
Published: March 2022

In the context of the current ocean-atmosphere cycle anomaly, exploring the potential teleconnections between climate indices and regional drought can help us know the variability of natural hazards more comprehensively to cope with them. This study explores the spatiotemporal patterns of drought and its multi-scale relations with typical climate indices in the Huaihe River Basin, China. The spatiotemporal variabilities of meteorological drought are identified using Empirical Orthogonal Function (EOF) and Continuous Wavelet Transform (CWT). The Cross Wavelet Transform (XWT) and Wavelet Coherence (WTC) analysis are used for investigating the multi-scale linkages between seasonal drought and climate indices, including Arctic Oscillation (AO), Bivariate El Niño–Southern Oscillation (ENSO) Timeseries (BEST), North Atlantic Oscillation (NAO), Niño3, Southern Oscillation Index (SOI), and sunspot number. Seasonal Standardized Precipitation Index (SPI)-3 during 1956-2020 are investigated separately for winter and spring seasons. We found that NAO mainly affects the interdecadal variation in spring drought, while AO and Niño3 focus on the interannual variation. In addition, Niño3 and SOI are more related to the winter drought on interdecadal scales. Our results prove that the onset, process, and intensity of El Niño or La Niña events influence the dryness and wetness conditions in the Huaihe River Basin. The results are beneficial for improving the accuracy of drought prediction, considering taking NAO, AO, and Niño3 as predictors for spring drought and Niño3 and SOI for winter drought.
Lithium element partitioning among haplogranitic melt, fluid and quartz
Authors: Cortes Calderon Edgar Alejandro , Ellis Ben S. , Ulmer Peter
Published: March 2022

Lithium (Li) is a key element in the production and development of high energy density storage technology. The boost in production of battery-powered vehicles has, as a result, increased Li demand. Felsic magma reservoirs are commonly linked to Li-bearing ore deposits as their major source of Li. Understanding the processes that may affect the Li inventory in magmas is, thus, crucial to improve exploitation of Li resources. We performed experiments using haplogranitic glass shards and quartz cores between 60-150 MPa and 750-950 ºC, involving fluids with salinities ranging 0.3 to 4.4 NaCleq m in externally heated MHC pressure vessels. Quartz cores were used in all experiments to trap synthetic fluid inclusions at equilibrium conditions by in-situ thermal-shock. Li partitions weakly into quartz, DLiquartz/melt ~ 0.02, with no apparent variation with studied pressures and temperatures within analytical error. LA-ICP-MS analyses on natural quartz from this study and published data show that Li concentrations in quartz from “hot and dry” rhyolites (e.g. Mesa Falls Tuff, Lava Creek Tuff, Weinheim Rhyolite) are higher than “cold and wet” rhyolites (e.g. Kos Plateau Tuff, Bandelier Tuff, Bishop Tuff, Young Toba Tuff, Oruanui Rhyolite), 25 ± 6 and 6 ± 5 ppm (n = 5300) in average respectively. Our DLiquartz/melt experimental results are one order of magnitude lower than natural dry-rhyolites but similar to the apparent DLiquartz/melt derived from natural samples in H2O-saturated systems, where hydrogen seems to play a more important role charge-balancing Al in point defects of quartz than Li. While Li is slightly incompatible with single-phase intermediate density fluids, Li partitions relatively strongly into hydrosaline fluids (HSF), DLiHSF/melt 5-12, within the two-phase fluids coexistence surface, with the highest values in the high temperature experiments. Although Li in HSF increases with temperature and, in turn, with chlorinity of the HSF, such a scenario does not affect greatly the inventory of Li in the run melts. The higher the temperature of the studied system at a given pressure, the lower the proportion of HSF with respect to low density vapor fluid (LDVF) in the system. Such topological consequence limits the “effective” extraction of lithium by fluids in felsic magma reservoirs to very constrained regions in pressure, temperature and fluid composition. As a result, extremely and ubiquitous high Li degassing from rhyolitic melts based on the Li concentration offset between re-homogenised melt inclusions and groundmass glass must be carefully revisited.
Detecting occurrence of blowing snow events with decision tree model
Authors: Xie Zhipeng , Ma Yaoming , Ma Weiqiang , Hu Zeyong
Published: March 2022

Blowing snow processes are crucial in shaping the strongly heterogeneous spatiotemporal distribution of snow and in regulating subsequent snowpack evolution in mountainous terrain. Although empirical formulae and constant threshold wind speeds have been widely used to estimate the occurrence of blowing snow in regions with sparse observations, these methods struggle to accurately capture the high local variability of blowing snow. This study investigated the potential capability of the decision tree model to detect blowing snow occurrence based on routine meteorological observations (mean wind speed, maximum wind speed, air temperature and relative humidity) and snow measurements. Results show that the maximum wind speed contributes the most to the classification accuracy, and the inclusion of more predictor variables improves the overall accuracy. Besides, the overall accuracy of blowing snow occurrence detected by the decision tree model is comparable or even better than traditional methods, indicating it is a promising approach requiring limited meteorological variables and having the potential to scale to multiple stations across different regions, such as the Tibetan Plateau.
Predictability of European Winter 2020/21
Authors: Ineson Sarah , Lockwood Julia , Stringer Nicky , Thornton Hazel , Scaife Adam
Published: March 2022

Winter (DJF) 2020/21 in the North Atlantic/European sector was characterised by the negative phase of the North Atlantic Oscillation (NAO). However, this was not well forecast by the leading seasonal prediction systems. We focus on forecasts from GloSea5, which was the Met Office operational seasonal prediction system at the time. Forecasts initialised in November 2020, at the 1-month lead time, indicated that a positive NAO was likely, although a few ensemble members did agree with the eventual outcome. Analysis suggests that the sudden stratospheric warming (SSW) that occurred in early January 2021 and an active MJO in late January/early February 2021 probably contributed to the observed negative NAO. In particular, GloSea5 indicated a rather low probability for SSW activity, which may well have been exacerbated by the forecast of a stronger than observed La Niña by this system.
Population, extension and some functional applications of DOSoReMI.hu, the renewed Hungarian Soil Spatial Data Infrastructure
Authors: Laborczi Annamária , Szatmári Gábor , Mészáros János , Takács Katalin , Takáts Tünde , Árvai Mátyás , Kovács Zsófia , Szabó Brigitta , Pásztor László
Published: March 2022

Hungarian Soil Spatial Data Infrastructure has been recently renewed in the frame of DOSoReMI.hu initiative. Soil property, soil type and functional soil maps were compiled. The set of the applied digital soil mapping techniques has been gradually broadened incorporating and eventually integrating geostatistical, machine learning and GIS tools and very recently spatially non-exhaustive ancillary observations, which has been also hypothesized to be successfully utilizable within DSM framework. (i) Vast, digitally processed legacy soil data, (ii) a spectrum library compiled by the measurements of 6600 soil samples with countrywide origin, (iii) and the results of a nationwide citizen science campaign targeted to collect proxy data on soil health were involved.

Soil property maps have been compiled partly according to international specifications (GlobalSoilMap.net, GSOC, GSASmap), partly to fulfill specific demands on the final products. Secondary (derived) soil features were also predicted. (i) Soil hydraulic properties were mapped applying generalized pedotransfer functions; (ii) spatial assessment of certain provisioning and regulating soil functions was carried out by the involvement of soil property maps in digital process/crop models. The nationwide, thematic digital soil maps compiled in the frame and spin-off of our research is utilized in a number of ways, for the support of national activities (LDN, SDGs, ESS assessment). A new soil portal was also elaborated for publishing of the created DSM products together with the result of their accuracy assesment.

Our paper will present

the new approaches for the population and extension of DOSoReMI.hu, and

various national functional applications of DOSoReMI.hu.

 

Acknowledgement: Our research has been supported by the Hungarian National Research, Development and Innovation Office (NRDI; Grant No: K 131820).
Assessing the solid-liquid discharge and rheological behavior of debris flow. A numerical model of a case study.
Authors: Zoratti Veronica , Bosa Silvia , Arnone Elisa , Petti Marco
Published: March 2022

The Friuli Venezia Giulia (FVG) region, located in the northeast of Italy, is characterised by frequent heavy precipitations that recurrently trigger debris flow phenomena. On August 2003, an intense rainfall concentrated in the north-eastern Julian Alps of FVG produced several floods and debris flow events, widespread on the entire basin of the Fella river watershed, with great economic damage and some casualties.

In the light of this, forecasting tools for the debris-flow analysis are useful with a view to a territorial planning. The general aim of our research is to develop a hydro-morphodynamical framework to study debris flow phenomena, which includes the hydrological modelling of the rainfall triggering event, the estimate of the solid-liquid discharge of the debris-flow and the hydraulic modelling of its propagation.

While previous works have accomplished the hydrological analysis, in the present study we focus on the evaluation of the solid-liquid discharge and the simulation of its propagation down the slope till its stop. Specifically, we considered a sub-basin of the Fella river watershed, the Uque at Ugovizza, and, in particular, a sub-area of the basin from which the debris flow that swept the village of Ugovizza in 2003 came off. The resulting liquid discharge obtained from the previous hydrological analysis was the input data to derive the solid-liquid discharge of the debris flow, which was assessed by using a formulation proposed in literature.

In order to study the propagation of the debris flow, we first identified a rheology model suitable to represent this kind of events. This was then implemented into an in-house numerical model, which integrates the bidimensional shallow water equations by means of finite volume techniques. Furthermore, an appropriate runout criterion was also assessed, so that the final stages of the phenomenon can be represented.

The first results of the application of the developed hydro-morphodynamic framework to this case study are presented and discussed.
The Music of Water
Authors: Renard Benjamin , Le Bescond Chloé
Published: March 2022

Visualizing hydroclimatic data through maps, curves, diagrams or any other graphical means is an integral part of most scientific analyses. While less frequently attempted, it is also possible to listen to the data through the process of sonification; and rather than just making sounds, why not trying to make music out of them?

Overall, the process of transforming a dataset into music involves two main steps. The first one is to define a mapping between data values and sound properties (typically, the volume or the pitch of notes). This is very similar to the approach used to visualize data (think about using the size or the color of a symbol to represent data). The second step is to arrange the raw result of this first sonification step in order to make it 'sound good' and -hopefully- transform it from sound to music. 

This poster will present a few musical pieces created from hydroclimatic data we use as part of our scientific activity, such as:

the most basic time series used in catchment hydrology (https://vimeo.com/481648928)

the impact of El Nino on precipitation (https://vimeo.com/440621263)

an exploration of the Dry Valleys of Antarctica (https://vimeo.com/653705727)

an ubiquitous statistical tool (https://vimeo.com/532773848)

and more (https://globxblog.inrae.fr/)

Data sonification can be looked at from many interesting angles. From a scientific perspective, it is another way to extract information from data. From a musical perspective, it is a device to create the backbone of musical pieces. From an education and communication perspective, it is an engaging starting point to present scientific concepts or results. In addition, the process of sonifying data is a great way to learn new skills in many topics, including signal processing, musical theory or computer science, just to name a few.
Unprecedented wildfire smoke in the Siberian Arctic in August 2021 
Authors: Popovicheva Olga , Kobelev Vasilii , Chichaeva Marina , Kasimov Nikolai
Published: March 2022

Long-range transport to the Arctic carries tracers of anthropogenic activities and wildfires, among other aerosol constituents. Black carbon (BC) shows a contribution of fossil fuels combustion and natural biomass burning (BB) to the Arctic atmosphere chemistry and aerosol pollution.  Fossil sources mostly prevail during winter-spring season while BB sources dominate during low BC concentration periods in summer. Spectral dependence of the light absorption described by the absorption Ångström exponent (AAE) is used to differentiate between different aerosol types (BC, BrC) and indicate the impact of BB.

Long-term airborne observations of BC in Northern Siberia have revealed a strong impact of forest fires in summer (Kozlov et al., 2016; Paris et al., 2009;Popovicheva et al., 2020). Particulate brown carbon (BrC) has been reported to be emitted by intense wildfires and measured in plumes transported over two days  (Forrister et al., 2015). Due to the mixing with background aerosol and ageing processes, the air masses influenced by BB events is expected to have increased AAE as compared to the BC produced by fossil fuel.

Yamalo-Nenets Autonomous Okrug (YNAO) is located in the Far North of Western Siberia, more than 50% of its area takes place beyond the Polar Circle. On August 4 of 2021, strong smoke enveloped Salehard, Noyabrsk, Tarko-Sale and other municipalities of the district. The air mass transportation from the southeastern directions brought smoke from forest fires located on the territory of the Republic of Sakha (Yakutia). According to the operational data of “Avialesokhrana”, 105 wildfires were active over an area of ​​about 1.2 million hectares there.

A dense haze covered a city Nadym, located around 100 km to the south the Polar Circle, as well. Smoke sampling performed from 5 to 12 August 2021 was correlated with the haze day duration and showed the variation of AAE up to 2.5, the feature of strong BB impact. Unprecedented high BC is observed on Bely island taking place in the Kara sea, above Yamal Peninsula. Unprecedented high pollution for the Siberian Arctic was recorded by research polar aerosol station “Island Bely”. An extreme increase of BC concentration was observed on August 5, reaching 4000 ng per m3. The Arctic summer background was exceeded 40 times!  It was found 8 times higher than the highest arctic haze concentrations observed in December 2019. AAE approached 1.4, very high value for area such remoted from wildfires (more than 1000 km). It indicated the long-range transportation from Yakutia of aged air masses influenced by BB events. Basic research in the Siberian Arctic is supported by Russia Geographical Society №17-2021И.

 
QBO/Solar Modulation of the Boreal Winter Madden-Julian Oscillation: The Role of Extratropical Wave Forcing in Late Fall / Early Winter
Authors: Hood Lon , Galarneau, Jr. Thomas
Published: March 2022

The tropical Madden-Julian oscillation (MJO) is the strongest of the intraseasonal climate oscillations.  It generates a Rossby wave train that can be associated with high-impact weather events at northern midlatitudes in winter and spring.  Here, we investigate using 41 years of ECMWF reanalysis data (1979-2019) why static stabilities in the tropical lower stratosphere are unusually low under easterly QBO and solar minimum conditions, leading to stronger MJO episodes.  Results indicate an important role for extratropical wave forcing events, including stratospheric warmings, occurring preferentially in late fall and early winter during QBOE and SMIN.  This increases the tropical upwelling rate beyond that caused by the QBO induced meridional circulation alone, further reducing lower stratospheric temperatures and static stability during northern winter.  In many but not all years, major sudden stratospheric warmings (SSWs) contribute significantly to the results obtained here.  Of the 11 clear QBOE years in the study period, six had SSWs in early winter prior to Jan. 15.  Of the 12 clear QBOW years, none had early winter SSWs while six had SSWs in late winter after Jan. 15.  There are two main implications of these results: (1) Observations of wave forcing and tropical static stabilities in late fall / early winter, combined with the known QBO and solar phases, may provide a means of projecting the likely strength of the MJO in a given winter; (2) A necessary prerequisite for a successful simulation of the QBO/solar - MJO connection in a global climate model may be the ability to simulate a preferred occurrence of extratropical wave forcing events, including SSWs, in early winter under QBOE and SMIN conditions. 