bluuebunny/crossref_metadata_2025 huggingface dataset:
European Biosphere Reserves - open air laboratories for tackling hydrometeorological hazards, OPERANDUM project
Authors: Pavlova Irina , Amirzada Zahra , Pulvirenti Beatrice , Ruggieri Paolo , Leo Laura Sandra , Kalas Milan , Di Sabatino Silvana
Published: March 2022

Hydrometeorological hazards such as floods, landslides and droughts are in many parts of the world occurring more frequently and more severely than in the past and are exacerbated by climate change. UNESCO-designated sites which focus on the protection and sustainable use of natural and cultural heritage are often partly or entirely exposed to natural hazards and extreme weather events, with potential impacts on the communities living in or near the sites, and on their livelihoods. Many natural UNESCO sites such as Biosphere Reserves and UNESCO Global Geoparks can serve as effective climate observatories and testing grounds for sustainable approaches including Nature-based Solutions (NBS).

NBS are based on the sustainable management, protection, and use of nature to mitigate environmental risks and preserve ecosystems, while providing environmental, social, and economic benefits, and building resilience to a changing climate. UNESCO promotes the uptake of integrated NBS for disaster risk reduction by leveraging local and scientific knowledge streams and participatory stakeholder engagement.

OPERANDUM is an EU-funded project supported by UNESCO that aims to deliver tools and methods to prove the efficacy of innovative NBS for multi-hazard hydro-meteorological risks in rural and natural areas. These so-called Open-Air Laboratories (OALs) comprise 10 rural territories, including two European Biosphere Reserves, where novel NBS practices are implemented and assessed through innovative monitoring systems and cutting-edge numerical modelling approaches.

The Po Delta Biosphere Reserve represents part of the OAL Italy where river flooding and subsequent salt intrusions driven by climate change and sea level rise threaten the livelihoods of local communities. Novel lab experiments have been developed to assess the ability of different plant species to function as effective natural barriers to salt intrusions and protect agricultural lands, reinforce the riverbank, and preserve inland water quality. In addition, advanced monitoring techniques and multi-scale impact modelling are deployed on site to estimate the impact of the NBS.

In an effort to promote upscaling of these solutions, OPERANDUM has developed an open-source online platform for NBS called the Geospatial Information Knowledge Platform (GeoIKP). Building on the knowledge acquired at the OALs, the platform offers a variety of cutting-edge services, interactive tools, customizable web-GIS functionalities, and standardized data repositories. It aims to serve as a hub for the global NBS community to share information, tools, data, and experiences to reduce hydro-meteorological hazards, and to address related societal challenges in rural areas.
Constraining plant water dynamics in land surface model by assimilating ASCAT dynamic vegetation parameters
Authors: Shan Xu , Steele-Dunne Susan , Huber Manuel , Hahn Sebastian , Wagner Wolfgang , Bonan Bertrand , Albergel Clement , Calvet Jean-Christophe , Ku Ou , Georgievska Sonja
Published: March 2022

Previous studies have shown that Advanced Scatterometer (ASCAT) C-band microwave normalized backscatter (σ40o), slope (σ') and curvature (σ'') provide a valuable insight into vegetation water dynamics. However, currently there are limited studies focusing on the observation operator linking land surface models to ASCAT observables to allow for their assimilation. In this study, an observation operator is developed based on a Deep Neural Network (DNN). It is trained using simulated land surface variables over France from 2007 to 2016. A version of the ISBA land surface model, operated by CNRM is used to produce these variables. This ISBA model version is able to simulate leaf area index (LAI) in addition to soil moisture. The ISBA simulations are forced by surface atmospheric variables from the ECMWF ERA5 atmospheric reanalysis. The performance of DNN is validated using independent data from 2017 to 2019. Model performance yields a near-zero bias in the estimation of σ40o and σ'. The sensitivity of the DNN is also investigated using the Normalized Sensitivity Coefficient. The analysis shows that the model estimates are physically plausible. ASCAT σ40o is sensitive to modeled surface soil moisture and LAI. Generally, the sensitivities vary as a function of season and land cover types. σ' is shown to be most sensitive to LAI. This is in agreement with earlier studies that concluded that σ' is a measure of vegetation density. In spring, water availability in root zone contributes the spring peak of σ', which is identified as the time of maximum branch water content in a previous study (Pfeil et al., 2021). Our results show that the DNN-based model is suitable for use as an observation operator in a follow-on data assimilation study to constrain plant water transport processes in the land surface model.
A worked example of an iterative, scripted approach to stochastic model development and deployment in a highly contentious decision-support setting.
Authors: Knight Jacob
Published: March 2022

A scripted development and deployment approach was used for developing the next-generation groundwater flow and land-surface subsidence model of the region surrounding Houston, Texas, USA.  The area has historically experienced substantial land subsidence resulting from groundwater use. Python scripts leveraging the FloPy and PyEMU packages were written to build and run the MODFLOW 6 model, perform very-high-dimensional parameter estimation and uncertainty analysis using PEST++, and process results. Automating these processes allowed for fast and repeated iterations through all or part of the modeling workflow for purposes including: troubleshooting input errors, testing hypotheses about the hydrologic system characteristics, evaluating the influences of structural model assumptions, and experimenting with different and increasingly complex formulations of the prior parameter distribution and likelihood functions in Bayesian sense. Automated generation and storage of processed output allowed easy comparison between iterations of the modeling workflow, and Git version control software provided a self-documented model repository with full-featured “undo” for returning to previous states of the workflow and investigating outcomes. The modeling team convened regularly (monthly to twice-weekly) to review results of the latest iteration and decide the next course of action. Model performance was improved steadily and incrementally by focusing on one new feature or problem per workflow iteration until modeling goals were met. This workflow style fostered a sense of predictability and confidence in the project outcome, a welcome departure from the “typical” numerical modeling process of panic and despair.
Determining Strain Accumulation Along NAF with Block Modelling
Authors: Ayruk Efe Turan , Özarpacı Seda , Özdemir Alpay , Özbey Volkan , Ergintav Semih , Doğan Uğur
Published: March 2022

The North Anatolian Fault (NAF) is a one of the major dextral strike-slip faults of Turkey which forming the boundary between the Eurasian - Anatolian plates. From 1939 to 1999, significant earthquakes occurred as showing a westward migration. Several studies are being conducted due to this seismic activity along the NAF. However, none of these are sufficiently dense to understand the behaviour of the fault. Here we present our block modelling results obtained from combine that published GNSS velocity datasets to determine strain accumulation along the NAF with TDEFNODE software (McCaffrey,1995). Our study area separates to 3 blocks, starts from east of the Sapanca Lake and includes the Karliova Triple Junction on the east, extends over the Black Sea on the north and 130 kilometers from the fault on the south. Checkerboard method is used to test the resolution of the dataset, then node distribution on the NAF is optimized and Wang’s model is used for inversion solution (Wang,2003). Euler Pole and block strain are estimated with inversion solution for Eurasia/Anatolia plates and the slip deficit variations are estimated for NAF. Under the constrain of the dense GNSS networks, we displayed that some segments of NAF are creeping up to shallow part of the crust and some other segments are locked at deeper region. Herein to better understand latest circumstance of complex slip deficit pattern of the NAF, estimated by our model, we evaluated our results under the complementary present and paleo-seismological datasets.

Keywords: NAF, block modelling, GNSS
Experimental and Numerical Investigation of Flux Partitioning Methods for Water Vapor and Carbon Dioxide
Authors: Bou-Zeid Elie , Zahn Einara , Ghannam Khaled , Chamecki Marcelo , Katul Gabriel , Thomas Christoph , Kustas William
Published: March 2022

The partitioning of ecosystem evapotranspiration and carbon dioxide fluxes into their plant and ground components is a critical research priority to better understand the water cycle and ecosystem function. Despite advances in different measurement techniques and partitioning models in the last decades, much is still unknown regarding the importance of different components of H2O and CO2 fluxes in ecosystems. In this work, we compare three partitioning methods that are based on analysis of conventional high frequency eddy-covariance (EC) data: the flux variance similarity method, the modified relaxed eddy accumulation methods, and the conditional eddy covariance method. First, we test these methods using fields experimental data, comparing them to other reference measurements for the components fluxes (gas chambers and leaf levels measurements). Subsequently, we develop a novel approach for simulating these fluxes in large eddy simulations and apply it to further probe the performance, assumptions, and relative skill of the three methods. The findings allow us to recommend partitioning best practices for their implementation, and to develop methods for the joint analyses of the various approaches.
Enhancing Data Sets From Rudna Deep Copper Mine, SW Poland: Implications on Detailed Structural Resolution and Short-Term Hazard Assessment
Authors: Sobiesiak Monika , Leptokaropoulos Konstantinos , Staszek Monika , Poiata Natalia , Bernard Pascal , Rudzinski Lukasz
Published: March 2022

Applying the software BackTrackBB (Poiata et al., 2016) for automated detection and location of seismic events to data sets from Rudna Deep Copper Mine, SW Poland, lead to an enhancement of existing routine catalogs by about a factor of 10.000 in number of events. Following our hypothesis that all types of seismic events contribute to seismic hazard in a mine, we included all events from major mine collapses (M>3), recorded blasting works and detonations, to machinery noise. These enhanced data sets enabled a detailed spatio-temporal distribution of seismicity in the mine and a short-term hazard assessment on a daily basis.

In this study, we focus on the data from two days with major mine collapses: the 2016-11-29 Mw=3.4, and the 2018-09-15 Mw=3.7 events. The spatio-temporal distribution of seismicity of both days deciphered detailed horizontal and vertical structures and revealed the increase of seismic activity after the daily blasting work. The daily histograms exhibit similar patterns, suggesting the dominant influence of explosions on the overall seismicity in the mine. Using the enhanced data sets for short-term hazard assessment, we observed gaps in the activity rates before the main shocks. They were followed by sudden increase of seismicity, a simultaneous drop in seismic b-value, and an increase in exceedance probability for the assumed largest magnitude events. This demonstrates the usefulness of enhanced data sets from surface networks for revealing precursory phenomena before destructive mine collapses and suggests a testing strategy for early warning procedures.
Soil – atmosphere exchange of greenhouse gases under future climates
Authors: Douwes Dekker Nine , Barba Josep , Kourmouli Angeliki , Mackenzie Robert , Gauci Vincent , Hamilton Liz , Pendall Elise , Yamulki Sirwan , Ullah Sami
Published: March 2022

This research investigates the cascading effects of elevated carbon dioxide (eCO2) fumigation of a mature temperature forest, with a particular focus on the fluxes of greenhouse gases (GHG) nitrous oxide (N2O), methane (CH4) and carbon dioxide (CO2). A field experiment was performed at the Birmingham Institute of Forest Research Free Air Carbon dioxide Enrichment facility (BIFoR FACE), where an oak dominated mixed mature woodland has been under eCO2 since 2017. Fluxes were quantified in situ using the Licor 8100A – an infrared gas analyser measuring total soil respiration (Rs) as CO2, and a Picarro greenhouse gas analyser (G2508), measuringN2O and CH4. Preliminary data from 2019 – 2021 have been analysed and are built on an earlier dataset from 2017-2018, and the role of soil temperature and soil moisture is considered. With more carbon allocation belowground, we expect an increase in microbial activity and consequently larger Rs. Overall, Rs was higher under eCO2 in 2017-2018; however, in years 2019 to 2021, the absolute difference in respiration between eCO2 and control plots gradually decreased and even switched in 2021, with a slight increase in Rs for control plots compared to eCO2 plots. Moreover, annual fluxes of N2O and CH4 were detectable and in general we observed N2O emission and CH4 consumption. My presentation will discuss Rs and N2O and CH4 fluxes and highlight the role of eCO2 as well as environmental and soil conditions that regulate the GHG fluxes, allowing us to compute the net global warming potential of forests under future climates.
Study of the interrelationships between NO2, SO2, HCHO and CHOCHO vertical column densities derived by car MAX-DOAS observations in and around the megacity of Lahore, Pakistan
Authors: Razi Maria , Dörner Steffen , Donner Sebastian , Ahmad Noor , Khokhar Fahim , Wagner Thomas
Published: March 2022

We measured the four trace species (NO2, SO2, HCHO, and CHOCHO) during two extensive car MAX-DOAS measurement campaigns in and around the megacity of Lahore. To our knowledge, CHOCHO was successfully measured from car-MAX-DOAS observations for the first time. The car-MAX-DOAS measurements were performed in summer 2017 and spring 2018. We retrieved the vertically integrated concentration (the so-called tropospheric vertical column density, VCD) of the trace gases along the driving routes from the measured spectra by using the so-called geometric approximation method. We present the results of the correlation analyses performed for all possible trace gas pairs. Strong correlations were found between the NO2-SO2 and HCHO-CHOCHO pairs.  The results indicate that NO2 and SO2 have common sources, most probably emissions from fossil fuel burning. Also, HCHO and CHOCHO have common sources, most probably secondary formation from common precursors like volatile organic compounds (VOCs).
Advances in X- and Ku- Band Radar Algorithms for SWE Retrieval
Authors: Kim Edward , Zhu Jiyue , Kang Do Hyuk 'DK' , Borah Firoz , Tsang Leung
Published: March 2022

Many sensing techniques, including active and passive optical and microwave sensing, are sensitive to snow—each with strengths and limitations.  The recent NASA SnowEx field campaigns, beginning in 2017, have provided valuable new field and airborne observations for evaluating various SWE sensing techniques and retrieval approaches.  In this paper, we focus on radar SWE retrieval using microwave volume scattering at X and Ku bands.  These bands and this approach have been the core part of past snow mission proposals to both the European Space Agency and to NASA, and are now the focus of a new NASA snow mission concept.

At the core of the algorithm is a dense media radiative transfer (DMRT) model.  The retrieval solution is determined through a cost function minimization approach after accounting for surface scattering from the snow-soil interface, low vegetation, and the scattering albedo.  We will show validation results using both tower and airborne data—including new results using SnowEx data--and discuss the options for obtaining the necessary input parameters.
Temporal Seismic Velocity Changes Associated with the Mw 6.1, 2008 Ölfus Earthquake Doublet, South Iceland, Using Ambient Noise
Authors: Cubuk Sabuncu Yesim , Jónsdóttir Kristín , Árnadóttir Þóra , Caudron Corentin , Lecocq Thomas , Mordret Aurelien
Published: March 2022

Our study presents temporal seismic velocity changes (dv/v) associated with the May 2008 Ölfus earthquakes by computing the cross-correlations of ambient noise. The 2008 Ölfus doublet (M5.8 and M5.9, with a composite magnitude of M6.1) occurred in the South Iceland Seismic Zone, which is a highly active transform zone that accommodates plate motion with major earthquake sequences (e.g., 1896, 1912, 2000). We investigate co-seismic and post-seismic response of the crust in the epicentral area, to the 2008 Ölfus doublet. For our analysis, we used three-component continuous data from three stations of the SIL national seismic network operated by the Icelandic Meteorological Office. Using the MSNoise software package (http://www.msnoise.org), we calculated single station ambient noise cross-correlations and utilized the stretching approach to quantify relative seismic velocity variations. We found the highest co-seismic velocity decrease (<1 percent) in the high-frequency band (1-3 Hz) at a seismic station located 10 km from the rupture zone. The co-seismic dv/v drop is also observed at stations 35 km away from the earthquake epicenter, though the amplitude of the variation is less, at 0.5 percent. We identify three months of post-seismic period in both the high-frequency and low-frequency calculations, indicating the recovery process at different crustal depths after the mainshocks. We compare our dv/v time series to continuous GPS observations, local seismicity, and volumetric stress changes. Our analysis suggests that the velocity changes are mainly controlled by shaking-induced damage. Our findings provide considerable insights into the time-dependent seismic velocity changes caused by the 2008 Ölfus events. This work is supported by the IS-NOISE project (https://is-noise.earth/) and the Icelandic Research Fund, Rannis (https://www.rannis.is/).
The enigmatic diapir-like structures in the Elovsky area (Lake Baikal): main characteristics and formation hypothesis 
Authors: Bulanova Irina , Solovyeva Marina , Akhmanov Grigorii , Vidischeva Olesya , Khlystov Oleg , Mazzini Adriano
Published: March 2022

Lake Baikal is the largest fresh water lake on Earth and has been target of numerous expeditions to investigate the mechanisms of diffused fluid migration that characterize large part of this basin. Among the numerous areas that have been investigated during the Training Through Research Class@Baikal program, here we report the findings from the Elovsky area located in in the northern part of the southern basin of the lake. Initial surveys in the area conducted geophysical investigations that revealed the presence of acoustic anomalies and enigmatic positive structures scattered on the lake floor. These are characterized by low-amplitude parabolic reflection over the bottom and sub-circular landforms with width of 200-300 meters and height of 10 to 25 meters. Seismic data also detected a buried lenticular semi-transparent sedimentary body (thickness of 30-90 meters) spread over most of the study area at a depth of 20-60 meters in average. This unit can be clearly distinguished from the parallel-layered seismic record of the host sediments, and is interpreted as a large landslide or a vast high-density gravity flow deposit. The structures described above are spatially confined to the area of spreading of the lenticular body, in connection with which we can assume their genetic relationship.

Bottom sampling targeted the topmost part of these positive structures and recovered layers of clayey silt and silty clayey silt and in some instances were retried very dense and compacted dry silt-clay, which is an unusual texture for the bottom sediments of Baikal. Gas extracted from these sediments revealed higher concentrations of methane, in particular at the topmost localities.

Based on the collected data we propose that the genesis of the Elovsky features is associated to clay diapir-like mechanism, somehow similar to that observed at mud volcanoes. The roots of this system reach the transparent landslide deposits. We argue that these deposits are likely gas saturated and triggered the slow extrusion of these compacted sediments.
On the elastodynamics of rotating planets
Authors: Maitra Matthew , Al-Attar David
Published: March 2022

We present a theoretical framework for modelling the rotational dynamics of solid elastic bodies. It takes full account of: Earth’s variable rotation, aspherical topography, and lateral variations in density and wave-speeds. It is based on an exact decomposition of the body’s motion that separates out the motion’s elastic and rotational components, in a way that we will make precise. As a prelude to the elastic problem, we show how Hamilton’s principle provides an elegant means of deriving the exact and linearised equations of rigid body motion, then study the normal modes of a rigid body in uniform rotation. We subsequently build on these ideas to write down the exact equations of motion of a variably rotating elastic body. We linearise the equations and discuss their numerical solution, before showing how to extend these ideas to analyse N elastic bodies interacting through gravity. We finally discuss the extensions that would be necessary in order to describe layered fluid-solid bodies, and discuss the applications of this work to problems of Earth rotation.
Eruptive vent openings during the 2021 Fagradalsfjall eruption, Iceland, and their relationship with pre-existing fractures
Authors: Hjartardóttir Ásta Rut , Dürig Tobias , Parks Michelle , Drouin Vincent , Eyjólfsson Vigfús , Reynolds Hannah , Jensen Esther Hlíðar , Óskarsson Birgir Vilhelm , Belart Joaquín M. C. , Ruch Joël , Gies Nils , Pedersen Gro B. M. , Einarsson Páll
Published: March 2022

The Fagradalsfjall eruption started on the 19th of March 2021 on a ~180 m long eruptive fissure, following a dike intrusion which had been ongoing for approximately three weeks. The eruption focused shortly thereafter on two eruptive vents. In April, new fissure openings occurred northeast of the initial eruption on the 5th, 6/7th, 10th, and 13th of April. The northernmost eruption occurred on the 5th of April, approximately 1 km northeast of the initial fissure, whereas the other fissure openings occurred between this and the initial eruptive vents. Stills from web cameras and time-lapse cameras are available for five of the fissure openings. These data show that the eruptions were preceded by steam emitted from cracks in the exact locations where the eruptions started. The time between the first steam observations and the visual appearance of glowing lava ranged between 15 seconds and 1.5 minutes during night observations and 9 to 23 minutes during daytime observations, the difference is likely explained by different lighting conditions. The eruptive vents are located where the north-easterly oriented dike intersected pre-existing north-south oriented strike-slip faults. These strike-slip faults could be identified on both pre-existing aerial photographs and digital elevation models. A high resolution ICEYE interferogram spanning the first day of the eruption in March reveals deformation where the later vent openings occurred in April. This indicates how Interferometric Synthetic Aperture Radar Analysis (InSAR) could be used to predict where subsequent vent openings are likely. This is of great importance for hazard assessment and defining exclusion zones during fissure eruptions.
Snowmelt timing influences the start of the Arctic-boreal fire season across North America
Authors: Hessilt Thomas D. , Rogers Brendan M. , Potter Stefano , Scholten Rebecca C. , Veraverbeke Sander
Published: March 2022

Snowmelt timing influences arctic-boreal ecosystem functioning through influences on surface hydrology and energy balance. Spring snow cover extent in the Northern Hemisphere has declined since the mid-20th century by up to 46 % in June, including a strong decrease after the mid-1980s. Regions of arctic-boreal North America have simultaneously experienced increases in the number and size of fires. With early snowmelt timing, the likelihood of early fire ignitions also increases as fuel is exposed and organic soil can begin to dry. Early fire ignitions can potentially develop into larger fires as a prolonged fire season may extend the period of favourable weather conditions for fire spread. Despite the importance of snowmelt timing, ignition timing, and fire size for predicting future boreal fire regimes across North America, these relationships are not well understood. Here we analysed snowmelt and ignition timing across ecoregions for boreal North America from 2001 to 2019. Using newly developed satellite-based fire products, we retrieved and matched ignitions with snowmelt timing in a spatially explicit manner.

            Results indicate that snowmelt timing has occurred 0.2 ± 0.17 days year-1 earlier in western arctic-boreal North America and 0.27 ± 0.33 days year-1 later in eastern arctic-boreal North America between 2001 and 2019. Similarly, we found that ignitions have occurred 0.61 ± 1.12 days year-1 earlier and 0.3 ± 0.58 days year-1 later for the western and eastern ecoregions. In 13 out of 16 ecoregions, there was a significant positive relationship (p < 0.01) between the timing of snowmelt and ignition. This suggests that snowmelt timing helps controlling the fire season start. The mechanisms behind the spatial gradient in the snowmelt timing over the last two decades are less understood and may result from differences in larger climatic oscillations influencing the polar front jet stream and Arctic sea ice extent. Decades of colder air temperature and higher amounts of winter precipitation may explain the later snowmelt and fire season start in the eastern ecoregions. Our results show that a shift in the snowmelt timing has resulted in earlier fire season starts in western boreal North America and in later fire season starts in eastern boreal North America.
Research on the heavy sands of the floodplain of the River Zambezi (Republic of Mozambique). Mining potential and economic evaluation.
Authors: Vaccaro Carmela , Zarlenga Francesco , Marrocchino Elena
Published: March 2022

In the last decades, the demand for raw materials, such as Heavy Metals (HM) and Rare Earth Elements (REE) is constantly grown due to the increasing demand from the new technologies. In particular, the REEs are mainly concentrated in apatite and zircon, largely present in pre-Paleozoic and Paleozoic cratonic rocks. Although many countries, such as Brazil, China and Iran have important deposits of HM and REE, they may only partially satisfy the increasing technology market demand. At present, extraction possibility is decreasing, and it is important to find new exploitable zones. For these reasons, mineral industries prefer to invest in exploration licenses before the mining activity.

Mozambique has a large and diverse mineral resource potential and is one of the most important exporting nations of raw materials.  Between 2009-2017 ENEA (National Agency for New Technology, Energy and Sustainable Economic Development) in collaboration with the University of Ferrara carried out explorative research to verify the presence of raw strategic materials in the Republic of Mozambique.

This research aims to investigate the sediments from the placer deposits of the Zambezi River in order to elaborate on the basis of analytical data an environmental friend extractive plan for mining activities that take into account also the environment and its preservation. The placer deposits are due to the mechanical agent, like marine, aeolian or lacustrine where minerals with high density and hardness, such as HM, are in high concentration, together with more than one economic mineral. The alluvial plain of the Zambesi River is characterized by the presence of sands, which contain heavy minerals in a percentage comprised of between 10-30%. A wide number of geochemical and mineralogical analyses (Diffractometry, XRF and ICP-MS) has been performed on samples, taken along 200 km of the river course. These data show a good presence of precious elements (Au, Ag, Pt, Pd, Os and Rh), a strong presence of minerals containing Fe and Ti, Zr, Hf and subordinately Ta, Ni and others. Moreover, Rare Earth Elements are present, in particular, is evident a good presence of Sc and Y from an economical point of view.
Which data assimilation method and data source for a multi-compartment hydrology/water quality model? Application on the PESHMELBA model in a small agricultural catchment
Authors: Rouzies Emilie , Lauvernet Claire , Vidard Arthur
Published: March 2022

Assessing pesticide transfers and fate in agricultural catchments is a major challenge to protect water ressources and aquatic organisms. To do so, physically-based, spatialized hydrological models are useful tools as they can be used to set up relevant mitigation strategies. The PESHMELBA model (Rouzies et al. 2019) is one such model that focuses on accurately simulating water and pesticide transfers both in the surface and the subsurface compartments of the soil. This model also aims at explicitely integrating and assessing the impact of landscape structures such as hedges, vegetative filter strips or ditches on transfers. To do so, the PESHMELBA model is characterized by a highly modular structure that relies on various code units standing for different physical processes in the different soil compartments. Such code units are thus coupled in a dedicated framework to reach a complete representation of the catchment with interacting processes. The resulting structure is quite complex and leads to significant difficulties to quantify and reduce the uncertainties associated to the simulation outputs.

In this study, we aim at setting a relevant data assimilation framework to reduce the uncertainty into the PESHMELBA coupled surface / subsurface water flow and reactive solute transport model. To do so, we test several data assimilation methods on hydrological and pesticide variables describing the catchment behavior. At first, these methods are implemented by combining the PESHMELBA model and surface moisture satellite images, at the small catchment scale. Different filtering and smoothing stochastic assimilation methods are explored: the Ensemble Kalman Filter, the Ensemble Smoother with Multiple Data Assimilation and the iterative Ensemble Kalman Smoother. Their abilities to retrieve moisture and pesticide concentration in the observed surface compartment but also in the deeper soil, that is not observed, are assessed. Furthermore, the conducted experiments also aim at retrieving some input parameters that characterize such different soil compartments.

Preliminary results on this part show that all tested methods only succeed in retrieving surface moisture. The Ensemble Smoother is shown to particulary outperform the other methods as it fully integrates the system dynamics. However, its performances are much more limited to retrieve moisture and input parameters in the deeper compartment due to poor correlations between the surface and the subsurface compartments. To overcome such limitation, other sources of data are gradually integrated in the DA framework. The process is proven successfull and we explore how the corrections from the DA process can propagate to other compartments such as the river streamflow and pesticide related variables .
Elevation-dependent warming in the tropical and subtropical Andes with CORDEX models
Authors: Palazzi Elisa , Toledo Osmar , Cely Toro Ivan Mauricio , Mortarini Luca
Published: March 2022

Several studies report on elevation-dependent warming (EDW), i.e., when warming rates change with elevation. This study assesses future EDW in the Andes, using an ensemble of regional climate model simulations belonging to the CORDEX experiment. EDW was assessed by calculating the (minimum and maximum) temperature difference between the end of the century (2071-2100) and the period 1976-2005 and relating it to the elevation. For the maximum temperatures, a positive EDW (enhancement of warming rates with elevation) was identified in both the western and eastern side of the tropical and subtropical Andes and in all seasons. For the minimum temperature, while a positive EDW was identified in the Subtropics (particularly in the western side of the chain), the Tropics are characterized by a negative EDW throughout the year. The tropical boundary marks a transition between discordant EDW behaviours in the minimum temperature. In the Tropics, EDW drivers were found to be different for the minimum temperature (Tmin) and for the maximum temperature (Tmax). Changes in Tmin  are mostly associated with changes in downward longwave radiation, while changes in Tmax are mainly driven by changes in downward shortwave radiation. This might explain the opposite EDW signal found in the tropical Andes during daytime and nighttime. Changes in albedo are an ubiquitous driver for positive EDW in the Subtropics, for both the minimum and the maximum temperature. Changes in longwave radiation and humidity are also EDW drivers in the Subtropics but with different relevance throughout the seasons and during daytime and nighttime. Besides the dependence on the latitude, we found that the western and eastern sides of the Cordillera might be influenced by different EDW drivers.
Scaling features of cosmic rays, solar, heliospheric and geomagnetic data
Authors: Modzelewska Renata , Krasińska Agata , Wawrzaszek Anna , Gil Agnieszka
Published: March 2022

Hurst exponent states one of the time series descriptors, allowing for the quantitative consideration of the state of the randomness, persistence or anti-persistence mode. This parameter has been used, in various types of real dynamical systems e.g., in financial analyses, solar physics or astrophysical processes. In our work we apply Hurst exponent to the revealing of the scaling features of cosmic ray intensity and anisotropy measurements by NMs over the solar cycle 24 (years 2007-2019). More precisely, using two different approaches: structure function and detrended fluctuation analysis methods we perform systematic calculation of Hurst exponent for selected physical parameters. Additionally solar, heliospheric and geomagnetic data are considered. Conducted analysis allows to identify periods with randomness and to obtain more complete picture of cosmic rays transport in the heliosphere and Earth magnetosphere throughout the solar cycle.
Classification of atmospheric circulation types over Europe in a CMIP6 Large Ensemble using Deep Learning
Authors: Mittermeier Magdalena , Weigert Maximilian , Küchenhoff Helmut , Ludwig Ralf
Published: March 2022

The 29 circulation types by Hess & Brezowsky, called “Großwetterlagen”, are one of the most established classification schemes of the large-scale atmospheric circulation patterns influencing Europe. They are widely used in order to assess linkages between atmospheric forcing and surface conditions e.g. extreme events like floods or heat waves. Because of the connection between driving circulation type and extreme event, it is of high interest to understand future changes in the occurrence of circulation types in the context of climate change. Even though the “Großwetterlagen” have been commonly used in conjunction with historic data, only very few studies examine future trends in the frequency distribution of these circulation types using climate models. Among the potential limitations for the application of “Großwetterlagen” to climate models are the lack of an open-source classification method and the high range of internal variability. Due to the dynamic nature of the large-scale atmospheric circulation in the mid-latitudes, it is highly relevant to consider the range of internal variability when studying future changes in circulation patterns and to separate the climate change signal from noise.

We have therefore developed an open-source, automated method for the classification of the “Großwetterlagen” using deep learning and we apply this method to the SMHI-LENS, an initial-condition single-model large ensemble of the CMIP6 generation with 50 members on a daily resolution. A convolutional neural network has been trained to classify the circulation patterns using the atmospheric variables sea level pressure and geopotential height at 500 hPa at 5° resolution. The convolutional neural network is trained for this supervised classification task with a long-term historic record of the “Großwetterlagen”, which covers the 20th century. It is derived from a subjective catalog of the German Weather Service with daily class affiliations and atmospheric variables from ECMWFs’ reanalysis dataset of the 20th century, ERA-20C.

We present the challenges of the deep learning based classification of subjectively defined circulation types and quantify the uncertainty range intrinsic to deep neural networks using deep ensembles. We furthermore demonstrate the benefits of this automated classification of “Großwetterlagen” with respect to the application to large datasets of climate model ensembles. Our results show the ensemble-averaged future trends in the occurrence of “Großwetterlagen” and the range of internal variability, including the signal-to-noise ratio, for the CMIP6 SMHI-LENS under the SSP37.0 scenario.
Juno Plasma Wave Observations at Ganymede
Authors: Kurth William , Sulaiman Ali H. , Hospodarsky George B. , Menietti J Douglas , Mauk Barry H. , Clark George , Allegrini Frederick , Valek Phil , Connerney John E. P. , Waite J Hunter , Bolton Scott J. , Imai Masafumi , Santolik Ondrej , Li Wen , Duling Stefan , Saur Joachim , Louis Corentin
Published: March 2022

The Juno Waves instrument measured plasma waves associated with Ganymede's magnetosphere during its flyby on 7 June, day 158, 2021.  Three distinct regions were identified including a magnetotail/wake, and nightside and dayside regions in the main magnetosphere distinguished by their electron densities and associated variability. The main magnetosphere includes electron cyclotron harmonic emissions including a band at the upper hybrid frequency, as well as whistler-mode chorus and hiss. These waves likely interact with energetic electrons in Ganymede’s magnetosphere by pitch angle scattering and/or accelerating the electrons.  The magnetotail/wake is accentuated by low-frequency turbulence and electrostatic solitary waves.   Radio emissions observed before and after the flyby likely have their source in Ganymede’s magnetosphere. 
Magnetic stratigraphy of the Samoedsky Formation, the upper part of the Siberian Traps LIP section in the Norilsk region
Authors: Latanova Elena , Latyshev Anton
Published: March 2022

The question of the total duration of the Siberian Traps magmatic activity in the Siberian platform and its correlation with the Permian-Triassic boundary is still being contentious, remaining essential for a number of studies, especially for the possible links with the end-Permian global biotic crisis.

The aim of this work was to obtain for the first representative and reliable paleomagnetic data on the section of the Samoedsky Formation using the modern instrumental base of paleomagnetic studies to estimate the magmatic activity duration. The Samoedsky Formation lies at the top of the Permian-Triassic volcanic section of the Norilsk region. The major part of the Norilsk tuff-lava pile, except for the lowermost Ivakinsky Formation, corresponds to the normal magnetic polarity interval [1]. Although the paleomagnetic investigation of the Samoedsky Formation basalts was performed previously [1, 2], this interval still remains complicated and the issue of its relation to the normal or reverse polarity interval has not been resolved.

During the field work oriented samples were taken (233 samples from 11 sites) from the lava flows of the Samoedsky Formation in the Verkhnyaya Talovaya river valley (the Norilsk region). At the laboratory stage alternating field and thermal demagnetization were carried out using SQUID SRM, JR-6 (AGICO) magnetometers and MMTD80 thermal furnace.

Based on the results of calculations with the Enkin software package [3], it can be concluded that the three uppermost lava flows of the Samoedsky Formation are magnetized in reversed polarity, which confirms the latest data [1]. Other studied flows demonstrate the normal polarity. Thus, the emplacement of the Samoedsky Formation and consequently the entire lava sequence of the Norilsk region corresponds not only to the LT1n1n chron (the first normal polarity chron of the Lower Triassic), but also to the part of the reverse polarity chron LT1n1r [1], which also affects the correlation of the sections of the Siberian Traps LIP different regions.

References

1. Latyshev A.V., Fetisova A.M., Veselovskiy R.V. Linking Siberian Traps LIP Emplacement and End-Permian Mass Extinction: Evidence from Magnetic Stratigraphy of the Maymecha-Kotuy Volcanic Section // Geosciences. 2020. V. 10. № 8. P. 295.

2. Gurevitch, E.L., Heunemann, C., Rad’ko, V., Westphal, M., Bachtadse, V., Pozzi, J.P., Feinberg, H. Palaeomagnetism and magnetostratigraphy of the Permian-Triassic northwest central Siberian Trap Basalts // Tectonophysics. 2004. V.379. P. 211–226.

3. Enkin R.J. A computer program package for analysis and presentation of paleomagnetic data. Pacific Geoscience Centre, Geol. Surv. Can., 1994. P. 16.

 
Modelling the regional paleoclimate of southern Africa: Sub-orbital-scale changes and sensitivity to coastline shifts
Authors: Göktürk Ozan Mert , Sobolowski Stefan Pieter , Simon Margit Hildegard , Zhang Zhongshi , Jansen Eystein
Published: March 2022

Paleoclimatic changes in South Africa, especially around the southern Cape region, are of intense interdisciplinary interest; as this is an important area in the context of human evolution, hosting a number of prominent archaeological sites such as Klipdrift Shelter and Blombos Cave (both located near today’s shoreline). Questions surrounding how large-scale and local variability (and change) influenced the local human populations are abundant. Here we present results from downscaling simulations performed for southern Africa, with a high resolution (12 km) regional climate model (WRF), forced by a global earth system model (NorESM). We focus on two time-slices, 82 and 70 ka BP, when orbital parameters and global sea level were markedly different from each other. Changes from 82 to 70 ka BP are generally in line with orbital forcing; indicating, for example, a widespread and significant (> 40%) increase in summer precipitation over inland southern Africa (south of 15°S) due to higher insolation at 70 ka BP compared to 82 ka BP. In contrast, the western and southern Cape coasts became drier at 70 ka BP, owing in part to a 40 m lower sea level, as the coastline shifted and the paleo-Agulhas plain got exposed. The effect of the coastline shift on temperatures in the southern Cape region is evident from the significant (up to 6°C) increases (decreases) in maximum (minimum) temperatures, which are strong enough to overwhelm changes arising from orbital forcing. These inferences are further supported with a separate set of coastline-sensitivity simulations at 70 ka BP, which indicate not only drying, but also larger diurnal and interseasonal temperature ranges when the coastline extends southwards, and once-coastal areas become more continental. For instance, at the archaeological site of Blombos Cave, temperature extremes (1st and 99th percentiles) of the modelled marine climate become 25 to 50-fold more probable to occur as the coastline shift leads to a continental climate. Our results indicate that regional to local-scale processes, which tend to not be represented in most coarse resolution global models, have a strong influence on the paleoclimate of southern Africa, highlighting both the coastal-inland contrasts and the importance of changes in coastline position. 
A probabilistic analysis of permafrost temperature trends with ensemble modeling of heat transfer
Authors: Groenke Brian , Langer Moritz , Gallego Guillermo , Boike Julia
Published: March 2022

Over the past few decades, polar research teams around the world have deployed long-term measurement sites to monitor changes in permafrost environments. Many of these sites include borehole sensor arrays which provide measurements of ground temperature as deep as 50 meters or more below the surface. Recent studies have attempted to leverage these borehole data from the Global Terrestrial Network of Permafrost to quantify changes in permafrost temperatures at a global scale. However, temperature measurements provide an incomplete picture of the Earth's subsurface thermal regime. It is well known that regions with warmer permafrost, i.e. where mean annual ground temperatures are close to zero, often show little to no long-term change in ground temperature due to the latent heat effect. Thus, regions where the least warming is observed  may also be the most vulnerable to rapid permafrost thaw. Since direct measurements of soil moisture in the permafrost layer are not widely available, thermal modeling of the subsurface plays a crucial role in understanding how permafrost responds to changes in the local energy balance. In this work, we explore a new probabilistic method to link observed annual temperatures in boreholes to permafrost thaw via Bayesian parameter estimation and Monte Carlo simulation with a transient heat model. We apply our approach to several sites across the Arctic and demonstrate the impact of local landscape variability on the relationship between long term changes in temperature and latent heat.
Metamodeling approaches to help designing vegetative filter strips and improve the water quality.
Authors: Lauvernet Claire , Helbert Céline , Xujia Zhu , Sudret Bruno
Published: March 2022

Significant amounts of pollutant are measured in surface water, their presence due in part to the use of pesticides in agriculture. One solution to limit pesticide transfer by surface runoff is to implement vegetative filter strips (VFS) along rivers. The sizing of these strips is a major issue, with influencing factors that include local conditions (climate, soil, etc.). The BUVARD modeling toolkit was developed to design VFSs throughout France according to these properties. This toolkit includes the numerical model VFSMOD, which quantifies dynamic effects of VFS site-specific pesticide mitigation efficiency. However, the toolkit is quite complex to use with many input uncertain parameters (quantitative - such as the slope, the Curve Number - or qualitative -such as the soil type or the rainfall event), making it not easy to use for risk management.

In this study, a metamodeling (or model dimension reduction) approach is proposed to ease the use of BUVARD and to help users design VFSs that are adapted to specific contexts. Different reduced models, or surrogates, are compared, based on Bayesian learning approaches or not: Polynomial Chaos Expansions, Mixed-kriging, and Deep-GP. Mixed-kriging is a kriging method that was implemented with a covariance kernel for a mixture of qualitative and quantitative inputs. Kriging and Deep-GP are built by couple of modalities and PCE and Mixed-kriging are built considering mixed quantitative and qualitative variables. As a last step, Finally, we perform a global sensitivity analysis with the help of the two surrogate models with the best accuracy. The results show that they give the same ranking of the importance of the input parameters.

The metamodel is a simple way to provide a relevant first guess to help design the pollution reduction device. In addition, the surrogate model is a relevant uncertainty tool, to visualize the impact that lack of knowledge of some parameters of filter efficiency can have when performing risk analysis and management.