bluuebunny/crossref_metadata_2025 huggingface dataset:
An ecosystem-based approach to support water quality assessment and management under climate and land-use condition
Authors: Critto Andrea , Pham Hung Vuong , Sperotto Anna , Torresan Silvia , Furlan Elisa , Marcomini Antonio
Published: March 2020

Freshwater ecosystems can be negatively affected by climate change and human interventions through the alteration of water supply and demand. There is an urgent need to protect the ecosystems, and the services they provide, to maintain their essential contribution to human wellbeing and economic prosperity, especially in a rapid and unpredictable global change context. In this work, we developed an integrated approach, coupling the outputs of ecosystem services (InVEST), climate (COSMO-CLM) and land use (LUISA) change models utilizing Bayesian Networks (BNs), to map freshwater-related Ecosystem Services (ESs), namely, water yield, nitrogen and phosphorus retention, and to assess their changes until 2050 under different management scenarios. First, InVEST was calibrated and validated with climate and land-use data to map and quantify ESs. Second, outputs of the ES model were integrated into the BN and the changes induced by different learning techniques and input settings were investigated. Finally, thousands of different scenarios were simulated testing multiple input variables configurations, thus allowing to describe the uncertainty of climate conditions, land-use change and water demand. Two types of inferences were conducted, namely, diagnostic and prognostic inference. The former permitted to find the best combination of the key drivers (i.e.  precipitation, land-use, and water demand) so that ESs are maximized while the latter concentrated on the quantification of ESs under different scenarios. This approach was applied and validated in the Taro River basin in Italy. The results show that the values of all the three types of ESs would decline in the medium-term period under most scenarios. Moreover, there would be a limit of space to improve those values, especially for nutrient retention services. The obtained results provide valuable support to identify and prioritize the best management practices for sustainable water use, balancing the tradeoffs among services. This analysis allows decision-makers to pick up one scenario with a specific configuration of land-use and water demand to optimize relevant ESs within their basin. Finally, these decisions are transformed into a “decision space” where the values of selected services are plotted in the space of ES to represent the gain/loss of each decision.
Water vapor transport in the turbulent planetary boundary layer (PBL) measured over heterogeneous terrain using multiple LiDAR systems.
Authors: Speidel Johannes , Vogelmann Hannes , Mauder Matthias , Perfahl Matthias , Wagner Timothy J. , Wanner Luise
Published: March 2020

Water vapor plays a crucial role for several processes on almost every scale of Earth's atmosphere. However, its turbulent transport throughout the PBL is at the same time particularly important and not very well understood. With the increasing resolution of numerical models arises the need for improved representations of the small-scale and nonlinear turbulent processes inside the PBL. Recent papers have shown that these refinements, predominantly on water vapor transport, are urgently needed as they are a limiting factor in the process of lifting numerical weather prediction to the next level.
 The CHEESEHEAD campaign, carried out in summer 2019, especially addresses the complex, turbulent land-atmosphere interactions over heterogeneous terrain and aims to close the energy balance. Therefore, a dense network of sensors has been installed measuring throughout the scales of the PBL with a multiple set of different measurement techniques.
 Within this proposed contribution, first results from the CHEESEHEAD measurements with a water vapor DIAL in combination with several Doppler wind LiDARs will be presented. The synergy of a virtual tower scanning geometry of the Doppler LiDARs right next to the water vapor DIAL delivers highly resolved data throughout the entire PBL. Therefore, special focus of this work lies on turbulent fluctuations inside vertical water vapor columns during the measuring time, spanning the entire PBL. This gives the additional opportunity to observe important entrainment processes at the very top of the PBL. Furthermore, this work deals with the calculation of vertical fluxes of latent heat. Therefore, the essential question whether this data is suitable for these calculations, which are highly sensitive towards temporal resolution, will be addressed. As a further step, aerosol and temperature data that have been measured with the same LiDAR system shall be integrated as well - aiming towards a comprehensive insight on relevant processes throughout the entire PBL. 
The INGV-RING GNSS Real-Time Services for geophysical
Authors: Cecere Gianpaolo , Avallone Antonio , Cardinale Vincenzo , Castagnozzi Angelo , D'Ambrosio Ciriaco , De Luca Giovanni , Falco Luigi , Famiglietti Nicola Angelo , Grasso Carmine , Memmolo Antonino , Minichiello Felice , Moschillo Raffaele , Selvaggi Giulio , Zarrilli Luigi , Vicari Annamaria
Published: March 2020

In the last 15 years, INGV has built an important geodetic research infrastructure (RING - Rete Integrata Nazionale GNSS) consisting of a distributed network over the national territory of more than 200 GNSS sensors. Data are recorded in real and quasi real-time in various INGV centre of acquisition, with the aim to provide geodetic products useful to the scientific community. Presently, RING provides daily GPS 30 seconds files distributed in Rinex format. Here we introduce a prototype service for broadcasts real-time streaming GNSS/GPS data from a subset of the RING stations. We will show two use cases of the services that are streaming for raw data exchange for the estimation of the Total Electron Content (TEC), and streaming of GNSS corrections for positioning in NRTK (Network Real Time Kinematic). GNSS signals at different frequencies can be used for the estimation of the Total Electron Content (TEC) due to the dispersive characteristics of the ionosphere. Real-time kinematic (RTK) positioning, instead, has been effectively used, and we will show some examples, for various research campaigns such as the precision positioning of seismic arrays, the real-time positioning of Unmanned Aerial Vehicles (UAV) used for topographic mapping, and landslide monitoring.
Significant temporal changes in glacio isostatic adjustment in Iceland during the 1950s to present
Authors: Geirsson Halldór , Valsson Gudmundur , Ófeigsson Benedikt G. , Sturkell Erik , Arnadottir Thora , LaFemina Peter C. , Hreinsdottir Sigrun , Drouin Vincent , Schmidt Peter , Lund Björn , Palsson Finnur
Published: March 2020

The two most widespread geodynamic signals in Iceland are caused by glacio isostatic adjustment (GIA; up to 4.5 cm/yr vertical motion) and tectonic plate spreading (approximately 1.9 cm/yr horizontal motion). GPS measurements of crustal deformation started in Iceland in 1986 and annually tens to hundreds of benchmarks are re-measured. Many of these surveys are on local scales, but the ISNET campaigns in 1993, 2004, and 2016 are the only island-wide efforts. Continuous GPS (cGPS) measurements started in 1995 and now over 100 cGPS stations are running. The cGPS allows for excellent quantification of seasonal variations in position with amplitude up to several cm closest to the glaciers, driven mainly by seasonal snowload. Frequent observations also help to observe temporal changes in uplift rates and correlate to glacier mass balance. In recent years InSAR has been applied to obtain both local signals (e.g., due to glacial surges) and island-wide estimates of GIA and plate motion. However, InSAR does not work under the glaciers where we expect the largest uplift. Regular GPS measurements at several nunataks on Vatnajökull started in 2008 and provide the only intra-glacier GIA observations in Iceland. Going further backwards in time is a challenge and relies on local levelling where relative uplift rates can be compared to current relative uplift rates to infer the temporal evolution.

During 1993-2004 the average observed uplift rates reached at most around 2 cm/yr and were likely at its lowest in the early 1990s, lower than during 1959-1991. During 2004-2010 the uplift rates increased on average by 70% compared to the previous time period. A thin layer of ash from the 2010 Eyjafjallajökull eruption enhanced the melting rates and is clearly seen as enhanced uplift rates during 2010-2012. Until 2014 the uplift rates remained high. In 2014 the average uplift rates lowered by around 20%. Comparable changes are observed in the horizontal deformation field. Overall, recent changes in GIA broadly follow changes in climate and mass balance. The first part of the 90s was cold and glaciers in Iceland were overall in equilibrium or gaining a bit of mass. After 1995 the glaciers started losing considerable mass every year. From 2011 the mass loss decreased; in 2015 there was a net mass gain, and in 2017 and 2018 the mass balance was close to equilibrium. The highly variable deformation rates call for a re-evaluation of the current GIA models, working towards a time-dependent response that can be applied to regional deformation studies.
Parameter values for ungauged catchments - comparing regionalization approaches using large-sample hydrology
Authors: Vis Marc , Pool Sandra , Seibert Jan
Published: March 2020

The parameterization of hydrological models in ungauged catchments remains challenging. However, the increased availability of large-sample data sets in recent years provides new opportunities for regionalization. In this study, we use the CAMELS dataset and the HBV model to simulate daily runoff in nearly 600 catchment areas in the United States. In a first step,  a lower and an upper benchmark were derived to obtain an approximation for how poor or how good runoff simulation could get in each of the catchments. For the upper benchmark the HBV model was calibrated, and the calibrated parameter values ​​were related to catchment characteristics. To account for parameter uncertainty, 100 independent calibrations were performed, and then median efficiency values ​​ were used for further analyses. For the lower benchmark the HBV model was run for 1000 randomly selected parameter sets, and median efficiency values were again used for further analyses. In a second step, each catchment was treated as ungaued and its parameter values were estimated by multiple regionalization methods. For each regionalization method donor catchments were selected based on a certain criterion including spatial proximity, similarity of hydrological signatures or attribute similarity. Additionally, we tested the added value of single discharge observations, which could be collected during short field visits. Furthermore, to analyze the theoretical limits of regionalization in general, the best three available donors of each receiver catchment were directly used to run simulations. All regionalization approaches were evaluated based on their relative performance with regard to the upper and lower benchmark.
First results indicated that the use of an ensemble of parameter sets calibrated in one of the gauged catchments leads to clearly better simulations than the use of randomly selected parameter values. Using the best three donor catchments resulted in nearly as good simulations as the upper benchmark, showing that regionalization has a high potential as long as we find a way to select these most suitable donors. The regionalization approach coming closest to the upper benchmark was based on a combination of spatial proximity and the use of single discharge measurements. Yet, there was still a considerable gap to the performance of using the best three donors. Despite the potential of regionalization demonstrated in this study, there still remains the challenge to find more reliable ways to link the hydrological functioning of catchments with the similarity of model parameter values.
BRIDGET: a toolbox for the integration and scaling of diverse in-situ evapotranspiration measurements
Authors: Hassler Sibylle K. , Dietrich Peter , Kiese Ralf , Mauder Matthias , Meyer Jörg , Rebmann Corinna , Zehe Erwin
Published: March 2020

Cross-compartment fluxes of mass and energy play a key role in the functioning of the earth system. Yet their understanding is largely hampered by the fact that related observations occur on multiple scales, involve multiple sensors, and data are collected across different research disciplines. Evapotranspiration (ET) is one of these fluxes and of key importance in the Earth’s water and energy cycle, and comparisons and scaling of in-situ ET measurements face the same challenges.

BRIDGET aims to provide tools that will allow storage, merging and visualisation of multi-scale and multi-sensor ET data and ultimately facilitate their scientific analysis. Approaches to estimate ET are manifold with respect to the underlying observations, scales, footprints and associated uncertainties, and measurements are gathered within various research disciplines. For this toolbox we therefore need to incorporate the appropriate metadata catalogue that describes the data comprehensively across disciplines. Special emphasis is placed on providing uncertainty estimates for the data, particularly when scaling functions are applied. Finally, we develop tools for visualisation including the different support of the measurements and (geo-)statistical analysis of the various ET data.

The BRIDGET toolbox is envisioned as a standalone python package but will also be implemented in an already existing virtual research environment (V-FOR-WaTer), facilitating the merging of different ET estimates across sensors and scales.
Millennial-scale oceanic CO2 release during marine isotope stage 3
Authors: Shuttleworth Rachael , Bostock Helen , Foster Gavin
Published: March 2020

During the last glacial period atmospheric CO2 and temperature in Antarctica varied together on millennial timescales, with CO2 abruptly increasing by 10-20 ppm in <1000 years in some cases. The exact causes of these rapid CO2 changes during a cold glacial climate remain unclear. Here we examine the role of ocean carbon storage and atmospheric exchange by applying the boron isotope-pH (CO2) proxy to Globigerina bulloides from core site TAN110628 located in the Pacific Sector of the Southern Ocean.  By reconstructing the surface carbonate system at TAN110628 at high temporal resolution (1 sample every 1 kyr) from 30 to 64 kyr we are able to fully constrain the nature of carbon leakage from the Sub Antarctic Zone of the Southern Pacific Ocean associated with these millennial-scale changes in atmospheric CO2.  This provides unique insights into the causes of abrupt changes in atmospheric CO2 during Marine Isotope Stage 3 and the last termination. 
Fitted Q-iteration for optimal water reservoir network operation under varying hydro-climatic conditions
Authors: Liang Bin , Giuliani Matteo , Zhang Liping , Chen Senlin , Castelletti Andrea
Published: March 2020

Although being one of the most important approaches to design optimal water reservoir operating policies, the Stochastic Dynamic Programming is challenged by the three curses of dimensionality, modeling, and multiple objectives that make it unsuitable in most practical applications. Increased hydrological variability induced by climate change and human activities further challenges the control of hydraulic infrastructures calling for more flexible and efficient approaches to operation design. Tree-based fitted Q-iteration (FQI) is a value-based, offline and batch mode reinforcement learning method, which employs the principles of continuous approximation of value function through non parametric randomized ensemble of regression tree, i.e. Extremely Randomized Tree. So far FQI has been used for relatively simple systems, including one dam and several state variables, and looking at historical hydrology. In this work, we explore the potential for FQI to design reservoir network operation under varying hydro-climatological conditions. The approach is demonstrated on a real-world case study concerning the optimal operation of a network of three water reservoirs in the Qingjiang River basin, China. Preliminary results show that the computational efficiency and performance of the policies derived by FQI are all satisfactory compare to traditional Stochastic Dynamic Programming, and the advantages in terms of computational efficiency and policies performance become more relevant when evaluated considering uncertain hydro-climatological and socio-economic conditions that requires using more information for conditioning the control policy. 
Enhancing the spatial resolution of actual evapotranspiration maps for Hungary
Authors: Csáki Péter , Czimber Kornél , Király Géza , Kalicz Péter , Zagyvai-Kiss Katalin Anita , Gribovszki Zoltán
Published: March 2020

Spatially distributed evapotranspiration (ET) data are crucial for the water balance calculations of the different ecosystems. The increasingly used remote sensing-based ET estimation methods allow to obtain information about spatial variability of ET at the field and regional scales. For Hungary, the most reliable actual evapotranspiration mapping model is the CREMAP (Calibration-Free Evapotranspiration Mapping), which uses MODIS surface temperature data. However, its 1 km2 resolution is too coarse to be effectively used for smaller scale operations such as precision forest management or agroforestry systems. Therefore, the CREMAP ET was statistically downscaled to the resolution of 250 m * 250 m with MODIS NDVI data as a co-variable. The downscaled data were used for the comparison of ET of different forest stand types during a dry period and a wet period.

The research was supported by the EFOP-3.6.2-16-2017-00018 for the University of Sopron project.
AREM: A user friendly toolbox for calculating anisotropy of magnetic remanence
Authors: Chadima Martin
Published: March 2020

A growing interest in isolating ferromagnetic fabric, i.e. magnetic fabric carried solely by ferromagnetic (sensu lato) grains, creates a need for optimization of laboratory protocols used to acquire the array of magnetic remanence vectors necessary to calculate the anisotropy of magnetic remanence (AMR) tensors. Before a laborious and tedious process of measuring large sample collections, several aspects shall be experimentally assessed, namely: (1) what type of magnetic remanence should be applied (e.g. isothermal, anhysteretic), (2) how magnetizing fields (AC and DC) control the acquired magnetization and its anisotropy, (3) how the viscous decay influences the measured remanence, and (4) how many and which magnetizing directions are necessary to obtain reliable and statistically sound AMR tensors. A careful examination of these factors considerably influences the quality of acquired AMR data. To facilitate the AMR tensor calculation, we present AREM – a simple and user-friendly toolbox embedded into Anisoft software. Prior to the tensor calculation, AREM provides a graphical visualization of a set of measured remanence vectors as spherical projections of unit vectors compared to the respective magnetizing directions and their intensity compared to the intensity of demagnetized state (background magnetization). The correction for the background magnetization is optionally done by a direct subtraction of measured background or by a mutual subtraction of antipodally magnetized vectors, if available. The AMR tensor is fitted by a least-square algorithm using a set of pre-selected full-vectors (full-vector method) or their projections to their magnetized directions (projection method). The calculated AMR tensors, including their confidence limits, can be immediately reviewed and processed using all features of the Anisoft software.
Investigation of structural changes of 21 atmospheric aerosol samples during a thermal-optical measurement procedure (EUSAAR2)
Authors: Haller Theresa , Sommer Eva , Steinkogler Thomas , Wonaschuetz Anna , Kasper-Giebl Anne , Grothe Hinrich , Hitzenberger Regina
Published: March 2020

Elemental Carbon (EC), Black Carbon (BC) and Organic Carbon (OC) contribute a large amount to atmospheric aerosols. Due to their significant influence on climate and health, a reliable measurement of these components is essential. Nevertheless, their correct determination is not trivial and results of different measurement techniques show differences by factors up to nine especially in the presence of Brown Carbon (BrC) (e.g. Reisinger et al., 2008; Hitzenberger et al., 2006; Wonaschuetz et al., 2009). EC and OC are usually measured with thermal-optical techniques: The sample is heated stepwise, first in an inert (He) atmosphere, then in an oxidizing (He+O2) atmosphere. The darkening of the sample during the heating procedure is traced with a laser transmission/reflection signal. Based on the progress of this signal, the amount of pyrolyzed carbon is calculated and attributed to OC in the subsequent evaluation. Despite this optical correction, the pyrolyzation of OC can lead to uncertainties in the OC/EC split (Cheng et al., 2012). Especially Brown Carbon (BrC) and water soluble organic carbons (WSOC) have a high tendency to pyrolyze and therefore bias the OC/EC split. Moreover several metal salts in the atmospheric aerosol can influence the measurement process and enhance or suppress pyrolysis of OC (Wang et al., 2010). These highly complex chemical and physical reactions are not fully investigated yet but are essential for a profound understanding of the biases in thermal-optical measurement techniques. 

The aim of the present study was to investigate the structural reorganizations of the carbonaceous materials in atmospheric aerosol samples occurring during a thermal-optical heating procedure (EUSAAR2, Cavalli et al., 2010) and to set them in relation with several properties of the samples such as ionic composition, EC, OC, BC and BrC, as well as the air mass origins during sampling of the atmospheric aerosol samples.
The changes of the internal structure of the material during the heating procedure of an EC/OC analyzer (Sunset instruments) were analyzed with Raman spectroscopy, which is sensitive to C-C bonding types and to the degree of structural ordering within the sample (Ferrari and Robertson, 2000). Different types of restructuration behavior were defined depending on the temperature levels of the EUSAAR2 protocol where measurable structural changes occur. For all samples ion chromatography was performed with a Dionex Aquion system (Thermo Fisher), BrC and BC were analyzed with the Integrating Sphere method (Wonaschütz et al., 2009) and air mass back trajectories for the respective sampling days were calculated with HYSPLIT.
The ERATOSTHENES Remote Sensing Supersite: Ground-truth observations over Cyprus
Authors: Mamouri Rodanthi-Elisavet , Nisantzi Argyro , Ansmann Albert , Bühl Johannes , Seifert Patric , Baars Holger , Amiridis Vassilis , Wandinger Ulla , Hadjimitsis Diofantos
Published: March 2020

Cyprus is strategically located in the region of the Eastern Mediterranean, the Middle East and North Africa (EMMENA). As a crossroad between Europe, Asia and Africa, it is representative of meteorological conditions and coastal areas in the EMMENA region.

Incomplete coverage with ground monitoring stations is the main limitation to make fast and significant progress in understanding the complex climate-relevant atmospheric processes around the globe and thus to improve atmospheric models used for climate change projections and extreme weather predictions. Although satellites can continuously monitor the atmosphere on a regional to global scale, they must be ground-calibrated and validated in order to incorporate satellite data into atmospheric models.

Cyprus, and especially Limassol as a coastal city, can be considered an ideal natural laboratory for advanced and comprehensive field studies on climate change, aerosol-cloud-dynamics-precipitation interaction, and the weather-precipitation-dryness complex, providing additionally valuable ground truthing observations for satellite missions.

The vision of the ERATOSTHENES Research Centre (ERC) in Cyprus is to become a Centre of Excellence for Earth Surveillance and Space-Based Monitoring of the Environment, in the framework of the EU H2020 Teaming project EXCELSIOR. Within this vision, a modern observational super site in Cyprus is of fundamental importance and will be build up for long-term profiling of the atmosphere (wind, humidity, aerosol and cloud properties, precipitation fields), in one of the hot spots of climate change increasing extreme weather events.

The ERATOSTHENES station in Limassol, Cyprus with the current instrumentation (EARLINET Raman depolarization lidar) follows the CAL/VAL activities of the AEOLUS satellite launched August 2018 through the participation to the VADAM project. Selected cases that demonstrate the complex aerosol and meteorological conditions over Eastern Mediterranean will be presented as well as lidar observations during AEOLUS overpasses over Cyprus.

Acknowledgements

The authors acknowledge the EXCELSIOR H2020-WIDESPREAD-04-2017: Teaming Phase2 project under grant agreement No 857510, ACTRIS and the ESA AEOLUS CAL/VAL VADAM project (27409). CUT team acknowledge Research and Innovation Foundation for the financial support through the SIROCCO (EXCELLENCE/1216/0217) and AQ-SERVE (INTERGRATED/0916/0016) projects.
On the calibration of an evaporation-based disaggregation method of SMOS soil moisture data
Authors: Stefan Vivien Georgiana , Merlin Olivier , Molero Beatriz , Escorihuela Maria-Jose , Er-Raki Salah
Published: March 2020

High resolution (HR) soil moisture estimates are needed by a range of agricultural and hydrological applications, considering it’s one of the drivers of evaporation, infiltration and runoff. Since the resolution of current remote sensing estimates (tens of kilometres) is insufficient for the majority of these applications, different downscaling techniques are used to improve the resolution. Amongst the existing methodologies, DISPATCH (DISaggregation based on a Physical And Theoretical scale CHange) has been proven to accurately improve the resolution of SMOS (Soil Moisture Ocean Salinity) soil moisture data, by using a soil evaporative efficiency (SEE) model. SEE can be derived from remotely sensed land surface temperature (LST) and normalized difference vegetation index (NDVI) data. DISPATCH uses two different SEE models: a temperature-based LST-driven model, and a soil moisture-based SMOS-driven model. This study aims at improving the robustness of the soil moisture-based SEE model, by testing different calibrations and models. Two SM-based SEE models, one linear and one nonlinear, are tested, each being calibrated from remote sensing data on a daily and on a multi-date basis. The approaches were implemented over two mixed dry and irrigated areas in Catalonia, Spain, and over a dry area in Morocco.  When looking at the two models in the daily calibration mode, the linear model performs better. Over the two areas in Spain, the correlation coefficients obtained with the linear model are 0.63 and 0.18 as opposed to 0.13 and -0.08, respectively. In Morocco, the correlation coefficients are roughly similar, 0.32 (linear mode) and 0.31 (nonlinear mode). The slopes of linear regression are also improved in the linear case, 0.44 and 0.88, as opposed to -0.14 and 0.11, for the Spanish sites. However, the best results were obtained in the case of the nonlinear model with an annual calibration. When comparing the linear and nonlinear models in the annual calibration mode, correlation coefficients are improved when using the nonlinear mode, from 0.13 and -0.08 to 0.78 and to 0.47 (Spanish site), and from 0.25 to 0.33 (Moroccan site). The slopes of linear regression are also improved, from 0.11 to 0.88, -0.14 to 1.15 (Spain) and from 0.53 to 0.74 (Morocco). The root mean square difference is generally low, ranging from 0.03 to 0.17 m3/m3. Considering several studies that report a strong nonlinear behaviour of the SEE with respect to SM, the nonlinear SM-based model in DISPATCH, combined with a multi-date calibration, is proven to give a significantly better performance, enhancing the robustness of the derived HR SM products.
Analytical solution technique in k-omega and k-epsilon turbulence parameterizations and their implementation in the OGCM
Authors: Gusev Anatoly , Zalesny Vladimir
Published: March 2020

The main purpose of the work is to improve the ocean general circulation model (OGCM) by including new parameterizations of heat, salt and momentum vertical turbulent exchange, which significantly affects quality of reproducing the ocean circulation and thermohaline structure using the OGCMs based on the primitive equation system. The main instrument of the research is the σ-model of the oceanic and marine circulation INMOM (Institute of Numerical Mathematics Ocean Model) developed at the Marchuk Institute of Numerical Mathematics of RAS. The basic equation set in the incompressibility, hydrostatics and Boussinesq approximations is supplemented with the equations for the k-ω and k-ε vertical turbulent exchange parameterizations, which are solved using the splitting with respect to the physical processes. The total equations are split into the stages describing transport-diffusion of the turbulent characteristics and their generation-dissipation. At the generation-dissipation stage, the equations for turbulent characteristics can be solved analytically. This approach allows one to solve the turbulence equations with the time step used in the OGCM. To estimate quality of these two vertical turbulent exchange parameterizations, the joint circulation of the North Atlantic and Arctic Ocean is numerically simulated and the upper ocean layer characteristics are studied. It is shown that the structure of large-scale fields in the North Atlantic and Arctic Ocean is sensitive to the choice between these two vertical turbulence models. In particular, application of the k-ε parameterization is accompanied by a noticeably higher rate of water involvement within the seasonal pycnocline in the developed turbulence zone than that resulting from application of the k-ω model.

The investigation is carried out in the INM RAS and MHI RAS under support of the Russian Science Foundation (grant No 17-77-30001).

References

Moshonkin, S., Zalesny, V. and Gusev, A., 2018, Journal of Marine Science and Engineering, 6(95), https://doi.org/10.3390/jmse6030095

Zalesny, V.B., Moshonkin, S.N., Perov, V.L. and Gusev, A.V., 2019, Physical Oceanography, 26(6), 455-466, https://doi.org/10.22449/1573-160X-2019-6-455-466
Deep learning for short-term temperature forecasts with video prediction methods
Authors: Gong Bing , Hußmann Severin , Mozaffari Amirpasha , Vogelsang Jan , Schultz Martin
Published: March 2020

This study explores the adaptation of state-of-the-art deep learning architectures for video frame prediction in the context of weather and climate applications. A proof-of-concept case study was performed to predict surface temperature fields over Europe for up to 20 hours based on ERA5 reanalyses weather data. Initial results have been achieved with a PredNet and a GAN-based architecture by using various combinations of temperature, surface pressure, and 500 hPa geopotential as inputs. The results show that the GAN-based architecture outperforms the PredNet. To facilitate the massive data processing and testing of various deep learning architectures, we have developed a containerized parallel workflow for the full life-cycle of the application, which consists of data extraction, data pre-processing, training, post-processing and visualisation of results. The training for PredNet was parallelized on JUWELS supercomputer at JSC, and the training scalability performance was also evaluated.
Impact of climate anomalies on the functionality of beech trees in a mixed forest in the Italian south-eastern Alps
Authors: Belelli Marchesini Luca , Valentini Riccardo , Frizzera Lorenzo , Cavagna Mauro , Chini Isaac , Zampedri Roberto , Gianelle Damiano
Published: March 2020

The increased frequency and severity of extremes climatic events determined by the current and predicted scenarios of global climate changes have a large potential impact on the functionality of forest ecosystems and on their capacity of providing ecosystem services. These include climate warming mitigation capacity of forests which is exerted through carbon sequestration, carbon storage and the regulation of the energy balance by allocating incoming solar energy into transpiration rather than thermal energy. Assessing the size of the effects of increasing atmospheric temperature and climate anomalies on the functionality of forests, both in the short and mid-term, as well as their resilience capacity, is therefore of utmost importance in ecological research. European beech (Fagus sylvatica L.) forests, extensively represented over the continent, are known to be particularly vulnerable to late frosts, which limit their distribution into continental areas, and droughts, especially in the southernmost area of their geographical distribution.

The object of this study is an alpine mixed forest at the site of Cembra (46.20N; 11.12E, 1250 m a.s.l) in the Trentino province (Italy). In May 2019 the forest experienced a late spring frost during the early development stage of beech leaves with resulting damage to canopies differing remarkably among individual plants. The ecological monitoring of beech trees started in June 2019 and has been since then carried out by means of clusters of traditional and Internet of Things based devices (Valentini et al. 2019) recording trees radial growth, sap flow density and characterizing the forest microclimatic space. The adopted experimental design consisted in the formation of two groups of trees (n=18) featuring contrasting damaged/undamaged canopies, all selected from the dominant or subdominant layer of the forest canopy structure.

Here we present the rates and the seasonal patterns of beech trees stem radial growth and transpiration from June to November 2019, highlighting the differences among plants directly dependent on the damage conditions and interpreting the total observed tree level variability in relation to microclimate, surrounding forest structure and microtopography. The functional recovery dynamics of transpiration and stem growth in damaged plants will be addressed as an initial evaluation of short-term resilience capacity of the beech forest .
Greenland ice sheet supraglacial lake drainages between 2000 and 2019
Authors: Brough Stephen , Lea James
Published: March 2020

The drainage of supraglacial lakes provides a fundamental mechanism for the rapid transfer of surface meltwater to the bed of an ice sheet, impacting both subglacial hydrology and ice dynamics. As a consequence, it is crucial to understand where and when these lakes drain, and how or if this has changed through time. Given that lakes are now occurring in greater numbers and at higher elevations, identifying changing modes in behaviour will have significant implications for the future dynamics of the Greenland ice sheet. Nevertheless, previous studies of supraglacial lakes and associated drainage events have been limited in spatial and/or temporal scale relative to the entire ice sheet.

Here we use daily maps of Greenland wide supraglacial lake coverage – derived from MODIS Terra within Google Earth Engine – to investigate the style, pattern and timing of lake drainages between 2000 and 2019. Results from this study: i) add to the understanding of how supraglacial hydrology and its coupling to the bed has changed in response to more extensive supraglacial lake cover over the last 20 years; and ii) provide insight into how these lakes and associated drainage events can be expected to respond to increased surface meltwater production under a warming climate.
The origin of the super-large Lijiagou spodumene pegmatite deposit in Songpan-Garze Fold Belt, West Sichuan, China
Authors: Fei Guangchun , Li Yunqiang , Menuge Julian F
Published: March 2020

The Lijiagou spodumene deposit in the central Songpan-Garze Fold Belt (SGFB), West Sichuan, is a spodumene pegmatite-hosted deposit within the giant Songpan-Garze polymetallic belt. Systematic zircon, cassiterite and coltan U-Pb dating, Hf isotope and whole-rock geochemical analysis were undertaken. Two-mica granite and muscovite albite granite have S-type granite affinities and chemical compositions suggesting a post-orogenic setting, and the spodumene pegmatites belong to the LCT (Li-Cs-Ta) group of pegmatites. Zircon LA-MC-ICP-MS U-Pb dating of the two-mica granite, muscovite albite granite, barren albite pegmatite and albite spodumene pegmatite give crystallization ages of 219.2 ± 2.3 Ma (MSWD = 0.55), 217 ± 2.8 Ma (MSWD = 0.47), 202.8 ± 4.9 Ma (MSWD = 3.9), 200.1 ± 4.6 Ma (MSWD = 3.1), respectively. Zircons from the same units yield εHf(t) values of  −39.17 to 13.84, −22.73 to −2.83, −11.17 to 8.14, and −4.92 to −2.4, respectively, consistent with mixed crustal sources for the pegmatite and granite magmas. Cassiterite from spodumene pegmatite yields a concordia intercept age of 211.4 ± 3.3 Ma (MSWD = 2.9), while coltan yields a weighted mean age of 211.6 ± 0.5 Ma (MSWD = 0.61). The U-Pb zircon ages of the two-mica granite and muscovite albite granite are interpreted as ages of magmatic crystallization. Metamictization of zircon in both barren and spodumene pegmatites makes their U-Pb zircon ages liable to inaccuracy due to Pb loss. The coltan U-Pb age is regarded as an accurate measure of the magmatic crystallization age of the spodumene pegmatite. Given the differences in magmatic ages and εHf(t) ranges between spodumene pegmatite and both the two-mica granite and the muscovite albite granite, the spodumene pegmatite probably represents an anatectic melt and not a fractionation product of either of the granitic magmas. U-Pb coltan and U-Pb cassiterite dating are more likely to provide accurate crystallization ages of spodumene pegmatites than U-Pb zircon ages. Spodumene mineral exploration in such geological environments requires consideration both of the mineralogy and geochemistry of potential metasedimentary source rocks, and of the effects of granite intrusion in creating fertile mineral assemblages.

Two key conclusions for spodumene pegmatite mineral exploration follow: 1) prior intrusion of granite may be required to generate a metasedimentary mineral assemblage that may later yield albite-spodumene pegmatite magma, and 2) a focus on the mineralogy and Li concentration of potential metasedimentary source rocks is required to identify geological environments in which albite-spodumene pegmatite magmas may have been generated.
Recent Developments of the Year of Polar Prediction
Authors: Jung Thomas , Goessling Helge , Werner Kirstin , Pasqualetto Sara , Kirchhoff Katharina
Published: March 2020

The Polar Prediction Project (PPP, www.polarprediction.net) is a 10-year (2013–2022) endeavour initiated by the World Meteorological Organization’s (WMO) World Weather Research Programme (WWRP). Aim of this wide international endeavour is to promote cooperative weather and sea-ice research enabling development of improved environmental prediction services for the polar regions, on time scales from hours to seasonal.

The PPP flagship activity, the Year of Polar Prediction (YOPP), has been launched in mid-2017 as a coordinated two-year period of intensive observing, modelling, verification, user-engagement and education activities. Since then, scientists and operational forecasting centers worldwide have closely worked together to observe, model, and improve forecasts of the Arctic and Antarctic weather and climate systems. During three Special Observing Periods in the Arctic and Antarctic, routine observations such as radiosonde launches and buoy deployments were enhanced (in the Arctic: 1 February ­– 31 March 2018 and 1 July – 30 September 2018, in the Antarctic: 16 November 2018 – 15 February 2019), aiming to close gaps in atmospheric and sea-ice observations and to enable significant progress in environmental prediction capabilities for the polar regions and beyond.

in mid-2019, PPP has moved into its Consolidation Phase which will be key for the success of the initiative. Central activities and projects such as the YOPPSiteMIP initiative or the EU-project APPLICATE will significantly contribute to improving forecasts of weather and sea-ice conditions in polar regions and to make them available to its user community. Data collected during YOPP are available for everyone through the YOPP Data Portal (https://yopp.met.no/) to feed into improved environmental forecasting systems.

In this presentation, an overview of the main achievements accomplished during the three YOPP Special Observing Periods, current activities including two more Special Targeted Observing Periods (TOPs) as well as prospects for future evaluations of PPP are provided.
Further development on sea-ice HBI biomarker proxies.
Authors: Sánchez-Montes Maria Luisa , Pedentchouk Nikolai , Mock Thomas , Belt Simon , Smik Lukas
Published: March 2020

Sea ice is a crucial component of the Earth’s climate system, which helps regulate global ocean and atmosphere’s temperature. The alarming decline in sea-ice extent and thickness under modern climate conditions has created the urgency to understand the long-term sea-ice variability and mechanisms of change. In recent years, the highly branched isoprenoid (HBI) lipid biomarker IP25 has emerged as a powerful proxy measure of past sea ice in the Arctic, and its analysis in a variety of marine sediments has provided the foundation for a large number of palaeo sea ice reconstructions spanning thousands to millions of years before present. To date, IP25 and related HBI-based studies have focussed largely on reconstructions of sea-ice extent and seasonal dynamics. Here we aim to further develop such sea ice proxies by measuring the changes in distribution and isotopic composition of HBIs in HBI-producing diatoms grown under different controlled laboratory conditions. We present preliminary results from the diatom Haslea ostrearia and outline the next steps of our research in the coming year.
Pre-existing fault-controlled eruptions from the lateral tips of a laccolith in SE Iceland
Authors: Twomey Vincent , McCarthy William , Magee Craig , Petronis Michael
Published: March 2020

Volcano eruption forecasting relies on models of sub-volcanic magmatic plumbing systems that link ground deformation to sub-surface magma movement. However, many of these models typically assume that eruption sites occur directly above laccolithic reservoirs. Furthermore, many of these models assume deformation of the host rock is exclusively elastic with few studies highlighting the role inelastic deformation (e.g., faulting/fracturing). Whilst the dynamics of magma flow have previously been well constrained in ancient in sub-volcanic systems, its geometrical and kinematic relationship with the corresponding host rock deformation remains poorly understood which, is critical to volcanic hazard assessment.

Here, we examine the structure of the shallow-level (i.e. intruded <1 km below the palaeosurface), silicic Reyðarártindur laccolith in SE Iceland, and demonstrate how the underlying mechanisms of lateral magma flow coupled with pre-existing host rock structures influenced the localisation of volcanic activity. In particular, we use anisotropy of magnetic susceptibility (AMS) fabric analysis and show that the intrusion contains several laterally emplaced magma lobes, with magma flowing along a SW-NE axis, parallel to the strike of pre-existing, steeply dipping fault arrays in the host basalt lavas. Lateral magma flow and inflation of the lobes promoted upward intrusion along these pre-existing faults, which we posit acted as preferential pathways for magma to reach eruption sites that were laterally offset by tens to hundreds of metres from the underlying main intrusion.

Our interpretation provides field evidence for the reactivation of pre-existing structures as inclined magma conduits to eruptive vent sites on the outer margins of subjacent lateral magma bodies. This supports seismic observations where (i) Volcanoes overlie the lateral tips of subjacent intrusions in subvolcanic systems; (ii) ground, and host rock deformation preceding eruptions can be most prominent in areas adjacent to the volcano site; and (iii) volcanoes overlie and are aligned along fault traces suggesting that pre-existing normal faults influence the localisation of volcanic activity.

 
Framework for improving land boundary conditions in regional ocean products
Authors: Campuzano Francisco , Santos Flávio , Ramos de Oliveira Ana Isabel , Simionesei Lucian , Fernandes Rodrigo , Brito David , Olmedo Estrella , Turiel Antonio , Alba Marco , Novellino Antonio , Tonani Marina , Lewis Huw , García Sotillo Marcos , Amo Baladrón Arancha , Dabrowski Tomasz , Jacob Benjamin , Staneva Joanna , Neves Ramiro
Published: March 2020

Currently hydrological models are not generally coupled to coastal and regional ocean models because, even if regarded as a powerful and useful tool, they do not fully accomplish to estimate accurately the right volume of water reaching the coastal zone for many reasons including water management activities such as human consumption, irrigation, etc. For this reason, many coastal and ocean models continue to use river climatologies as boundary conditions for representing such an active boundary. Furthermore, continuous salinity observations in the coastal area are scarce and sensors are highly unreliable while current Earth Observation (EO) products for salinity poorly represents the coastal gradients.

In this presentation, the current state-of-the-art and the results of the LAMBDA Project (λ) (LAnd-Marine Boundary Development and Analysis) will be shown. The main aim of the project was to demonstrate an improvement in the thermohaline circulation in coastal areas by a better characterisation of the land-marine boundary conditions, with special regard to the salinity fields. The LAMBDA project analysed the opportunity of improving the land-marine boundary conditions by exploring the capacities of state-of-the-art hydrologic models. In order to achieve those objectives, the project strategy used an integrated approach that went from watershed models to validation in the coastal area by fit-for-purpose EO products, developed by SMOS, and passing through methods and proxies for integrating the freshwater flows into regional mesoscale grids. The watershed and estuarine proxies were modelled using the MOHID Water modelling system (http://www.mohid.com/) an open source model capable of simulating a wide range of processes, i.e. hydrodynamics, transport, water quality, oil spills, in surface water bodies (oceans, coastal areas, estuaries and reservoirs).

The project products were evaluated in Portugal Continental waters, tested in CMEMS regional products and evaluated by local experts in Germany, Ireland, Portugal, UK and Spain.