bluuebunny/crossref_metadata_2025 huggingface dataset:
Structuring a Bayesian belief network using expert knowledge for landslide hazard assessment
Authors: Choudhury Shreyasi , Malamud Bruce D. , Donovan Amy
Published: March 2021

Landslide hazard assessment in India using historical data faces three challenges: (i) difficulty of obtaining systematic landslide occurrence data; (ii) under-representation of small-scale landslides; (iii) lack of recording of the physical/anthropogenic influences on landsliding. Here we show development of a Bayesian Belief Network (BBN) for a multi-hazard landslide assessment using experts’ judgements. Experts were chosen based on their experience on landslides and/or in Darjeeling Himalayas. A BBN produces a probability estimation of possible events and is a graph containing a set of variables (nodes) and conditional (in)dependencies between the nodes (arcs).

To better understand the relative weighting of potential causes of landslides in our case study area -Darjeeling Himalayas- we carried out four steps. (Step 1) We reviewed 29 peer- and grey-literature sources to list 13 physical/anthropogenic variables that might influence landsliding. (Step 2) We interviewed 11 experts about the importance of these 13 variables and asked for additional potential variables (resulting in 35 variables). (Step 3) We used interviews plus questionnaire to ask 16 experts to rate each of the 35 variables (scale 1-10) as to their potential to influence landsliding. The experts also added 7 more variables (resulting in 46 variables). (Step 4) Based on the ratings and interviews, we chose 35 out of 46 variables as our BBN nodes and from these the BBN arcs. Examples of these variables include rainfall, wildfires, geological weathering, planned infrastructure loading, cultivation (planned/unplanned), railway/road construction changing slope angle (planned), relief, slope, soil cohesion. Based on this study, we found that judgement of local people/academicians/technical experts can be of help whilst developing a BBN structure, allowing us to calculate probabilistic relationships between the nodes in a BBN. This process, therefore, can be utilised for landslide-based multi-hazard assessment in low data regions.
Global Deforestation Revisited: The Role of Political and Institutional Factors
Authors: Moreira Dantas Ianna Raissa , Söder Mareike
Published: March 2021

In times of international agreements and efforts to mitigate climate change and meet sustainable development, ecosystem management and forest conservation deserve special attention to promote human and environmental sustenance. Tropical forests have been declining worldwide, and biodiversity is under constant threat. Understanding the future potential of environmental services requires analysis of the relationship of socioeconomic drivers and anthropogenic land use change (LUC). Population and economic growth, agricultural production, and human capital have a dual relationship of cause and consequence with LUC. Likewise, changing patterns of land use, through agriculture and silviculture activities, is directly associated to market and technical progress, but also to political, institutional, and socioeconomic development. Studying such relationships enhances the analyses on the ability of institutional factors to promote environmental conservation, economic growth, and social welfare. Studies on LUC are historically based on physical variables; however, institutional and political drivers have shown to be core to forest degradation. The present paper aims at investigating the role of physical and institutional factor on global deforestation. This paper draws from recent global remote sensing data on land use from ESA Climate Change Initiative (ESA/CCI) from 1992 and 2015. To assess drivers of deforestation, we employ a logit model regression accounting for a global spatially explicit dataset on land use, regressed with physical, economic, and socioeconomic variables. We make use of the suitability indicators calculated by IIASA for different agricultural crops within the Global Agro-Ecological Zones modelling. As institutional factors we consider areas under protection based on spatial datasets provided by UNEP and wetland international, and include the country level corruption index of Transparency International. Our preliminary analysis shows that institutional instability is significantly related to LUC. In areas where land should be under protection due to non-market ecosystem services, political instability is likely to stimulate land use. Likewise, insecurity in land tenure might lead to a short-term maximization of profits, through full deforestation and exploitation of the soil fertility, instead of a long-term sustainable use.
Global Freshwater Fluxes into the World Oceans
Authors: Recknagel Thomas , Dornblut Irina , Müller Schmied Hannes , Döll Petra , Looser Ulrich , Plessow Henning
Published: March 2021

The Global Runoff Data Centre (GRDC) deploys the data product Global Freshwater Fluxes into the World Oceans since 1996. The quantification of freshwater fluxes into the ocean is an important link to oceanography and climatology, as the salinity of sea water influences ocean currents and is a driver of evaporation and therefore interconnects to the general circulation of the atmosphere.
The first versions of the data product were based on runoff coefficient estimates for ungauged basins. Since 2004, results of the global hydrological model WaterGAP (AG Hydrologie, Goethe-Universität Frankfurt), calibrated with GRDC station data, were used to calculate the freshwater fluxes.
On the basis of the latest WaterGAP 2.2d model, we could now derive the freshwater fluxes in a refined temporal resolution and for a considerably extended time period (1901-2016).
We present a statistical analysis of monthly and annual freshwater input to the oceans within 5° and 10° latitude zones, from 5° cells along the coastlines and from the Global International Water Assessment regions (GIWA).
Beyond that, the GRDC has revised its GIS product Major River Basins of the World, which is now consistent with the WMO Regions and Subregions. The freshwater fluxes have been determined likewise for these catchments.
The provision of integrative data products is one of the objectives of the Global Terrestrial Network Hydrology (GTN-H) corresponding with the commitments of the WMO members at the eighteenth session of the World Meteorological Congress.
Effectiveness of residential heating emission reduction scenarios in Poland 
Authors: Durka Pawel , Kaminski Jacek W. , Jeleniewicz Grzegorz , Struzewska Joanna , Kawka Marcin , Jagiello Paulina , Gienibor Aneta , Norowski Aleksander , Szymankiewicz Karol , Gawuc Lech
Published: March 2021

The residential sector is one of the most important emissions sources affecting air quality in Poland. 

According to KOBiZE IEP-NRI, in 2018 this sector accounted for 63% and 82% of the national totals for PM10 and PM2.5. 

 

We attempted to assess the impact of the national “Clean Air” Programme that focuses on the replacement of old solid-fuel furnaces and boilers.

 

The proposed scenarios assumed that the heating devices were replaced in approx. 2 million single-family houses. A random selection of the building was applied:

Scenario-1 - emission reduction for all administrative units in Poland. 

Scenario-2 - emission reduction for administrative units were the annual average PM2.5 concentrations in 2019 exceeded the threshold of 20 µg/m3

The emission factors were changed to represent the fuel standards set for modern heating systems. The GEM-AQ air quality model was used as a computational tool (Kaminski et al. 2008). 

 

We will present the scenario effectiveness based on different metrics. The implementation of emission reduction in the residential sector would significantly reduce health exposure due to PM10, PM2.5, and B(a)P dust. Due to the assumptions regarding the fuel mix of new installations, the background concentrations of nitrogen oxides and ozone would slightly increase, but this would not change the exposure.
Physics, Resolution and Data Assimilation: Making sense of Greenland climate and ice sheet Surface Mass Balance with HARMONIE Climate
Authors: Mottram Ruth , Landgren Oskar , Anker Pedersen Rasmus , Pagh Nielsen Kristian , Bøssing Christensen Ole , Olesen Martin , Boberg Fredrik , Hansen Nicolaj , Amstrup Bjarne , Yang Xiaohua
Published: March 2021

The development of the HARMONIE model system has led to huge advances in numerical weather prediction, including over Greenland where a numerical weather prediction (NWP) model is used to forecast daily surface mass budget over the Greenland ice sheet as presented on polarportal.dk. The new high resolution Copernicus Arctic Reanalysis further developed the possibilities in HARMONIE with full 3DVar data assimilation and extended use of quality-controlled local observations. Here, we discuss the development and current status of the climate version of the HARMONIE Climate model (HCLIM). The HCLIM system has opened up the possibility for flexible use of the model at a range of spatial scales using different physical schemes including HARMONIE-AROME, ALADIN and ALARO for different spatial and temporal resolutions and assimilating observations, including satellite data on sea ice concentration from ESA CCI+, to improve hindcasts. However, the range of possibilities means that documenting the effects of different physics and parameterisation schemes is important before widespread application. 

Here, we focus on HCLIM performance over the Greenland ice sheet, using observations to verify the different plausible set-ups and investigate biases in climate model outputs that affect the surface mass budget (SMB) of the Greenland ice sheet. 

The recently funded Horizon 2020 project PolarRES will use the HCLIM model for very high resolution regional downscaling, together with other regional climate models in both Arctic and Antarctic regions, and our analysis thus helps to optimise the use of HCLIM in the polar regions for different modelling purposes.
Geometric Evaluation of Hagia Sophia
Authors: Uncu Gulen , Çaktı Eser
Published: March 2021

Hagia Sophia is one of the most prominent architectural and structural creations in the history of mankind. Since it has been standing for the last 15 centuries, it is noteworthy to be worked on. Hagia Sophia is known to be located on eartquake zone and has high level of deformation since it has been constucted. Therefore, learning its mystery requires a great variety of analysis. Besides, instead of studying on the ideal geometry of the structure, it would be more enlightening to reveal the real deformed shape of it. An important point to be considered is using non-destructive techniques. Hence, 3D laser scanning is an effective method for this purpose. This study aimed to observe the designed and the deformed geometry of Hagia Sophia. First the structure is scanned by 3D laser scanner from both inside and outside. The point clouds obtained by each scan are combined by Cyclone software. This part of the study covers the process after the combined point cloud is meshed on 3D Reshaper software. The software allows the user to measure every detail, moreover creating ideal geometric shapes for each element is possible. In this study, the structure is first observed in detail of each structural element, then as a whole. It is seperated as primary and secondary system. In the title of primary system, first the main piers are examined, then the main arches, the main dome and dome base, tympana and the pendentives. The secondary system covered the secondary piers, secondary domes, exadrae domes, barrel vaults and the buttress piers. According to the element, the ideal geometric shapes are created like ideal vertical planes for the piers, ideal cylinders for the arches, ideal sphere for the dome etc… The comparison of the ideal geometry and the real one points the deformation. Hence, the study reveals the deformation that Hagia Sophia has undergone during the centuries.  Besides, when the ideal geometric shapes are considered as a whole, they form a consistent design. Once the shapes created seperately joined together,  they agree in the center of the structure, which supplies a satisfying verification about the study. Therefore it might give a clue about the designed geometry of Hagia Sophia. Consequently, this study will improve the structural analysis of Hagia Sophia based on more realistic data in terms of geometry.
Estimation and Comparison of Entropy-Based Parameter Estimation for Kappa Distribution over Krishna River Basin
Authors: Singh Amit , Chavan Sagar
Published: March 2021

The Kappa distribution is a versatile distribution and results in nine different distributions depending on its parameter values.The study presents an entropy-based method for estimating the parameters of the four parameters kappa distribution. At site data of the annual maximum flood of 30 sites of Krishna river basins are used for the study. The parameters estimated using the principle of maximum entropy (POME), method of moments, L-moments, and method of maximum likelihood is compared using Kolmogorov-Smirnov (K-S) test. The overall performance of the methods POME, MLE and L-moment are found to be comparable, whereas MOM performs with the highest bias; both the entropy method and the L-moment method allows the four-parameter kappa distribution to fit the data well and the combination of the two methods can further improve the parameter estimation of the four-parameter kappa distribution.
On the need of new educational curricula in the field of space technologies and their applications.
Authors: Tramutoli Valerio , Capece Nicola , Colonna Roberto , Erra Ugo , Filizzola Caroilina , Lacava Teodosio , Masiello Guido , Satriano Valeria , Scanniello Giuseppe , Serio Carmine
Published: March 2021

The need of dedicated educational curricula in the field of space technologies and their applications was identified as a gap in the official European offer already in 2013 when the Virtual GMES Academy concept was launched with the Salzburg protocol in the framework of EU4Regions project. Since then, the goal to fill this educational gap (no official academic courses are presently offered covering all the aspects of Space Technologies from the mission design up to the applications developments) has been included, as a pillar, in the European Copernicus-uptake strategy, After the start of the European network of Copernicus Academies, the EO4GEO project took the initiative to design the Body of Knowledge (BoK) to be at the base of new specific educational curricula and well identified skills in the field. 
The present status of development of Bok, its relevance even for non-EU and particularly for developing countries, is here discussed and presented. 
Fossil fish species and assemblage are relevant integrative paleo-biogeo-archives in ancient lakes
Authors: Otero Olga
Published: March 2021

In paleontological context, fish remains are frequently collected and constitute a large part of the lake macro-fossil assemblages. In the presentation, examples from continental Africa chosen in lakes of different dimension, shape and history (mainly Malawi, Chad and Turkana) will illustrate how fish fossil study potentially provides a wide range of information on the paleoenvironment (water salinity, temperature, oxygenation, seasonality, etc.) and the paleogeography (watershed connections) of the lake and its basin. It is based on the knowledge of the ecology and phylogeny of the species and through dedicated biogeochemical and sclerochronological studies of their bones and teeth that also constitute paleo-bio-archives that recorded certain environmental information. Alongside the results extracted from each dedicated study, their combination provide new information and show the gain of extracting different and independent informations from the same object or from objects from the same assemblage, and notably in the case of lake-fish assemblages. For example, the combination of the knowledge on a fish paleo-ecology in a lake with results of a biogeochemical study of their remains can evidence change in the hydrographical regime between successive lake deposits. Finally, fish study also allow an interpolation of change in paleoenvironments at different time scales and their integrative study as paleoenvironmental proxy should be more widely included in the evolution of lakes in the past. The multi-time scale and proxy study enabled on fossil fish is sensible for transfer to predict modern lake evolution.
KuKa altimeter mode data gathered during MOSAiC: scattering from snow covered sea ice and snow depth determination using dual-frequency and polarimetric approaches
Authors: Willatt Rosemary , Stroeve Julienne , Nandan Vishnu , Tonboe Rasmus , Hendricks Stefan , Ricker Robert , Mead James , Newman Thomas , Itkin Polona , Liston Glen , Mallett Robbie , Zhou Lu , Schneebeli Martin , Krampe Daniela , Tsamados Michel , Demir Oguz , Oggier Marc , Buehner Gattis Ella , Wilkinson Jeremy
Published: March 2021

Retrieving the thickness of sea ice, and its snow cover, on long time- and length-scales is critical for studying climate. Satellite altimetry has provided estimations of sea ice thickness spanning nearly three decades, and more recently altimetry techniques have provided estimations of snow depth, using dual-band satellite altimetry data. These approaches are based on assumptions about the main scattering surfaces of the radiation. The dominant scattering surface is often assumed to be the snow/ice interface at Ku-band frequencies and the air/snow interface at Ka-band and laser frequencies. It has previously been shown that these assumptions do not always hold, but field data to investigate the dominant scattering surfaces and investigate how these relate to the physical snow and ice characteristics were spatially and temporally limited. The MOSAiC expedition provided a unique opportunity to gather data using a newly-developed Ku- and Ka-band radar 'KuKa' deployed over snow-covered sea ice, along with coincident field measurements of snow and ice properties. We present transect data gathered with the instrument looking at nadir to demonstrate how the scattering characteristics vary spatially and temporally in the Ku- and Ka-bands, and discuss implications for interpretation of dual-frequency satellite radar altimetry data. We compare KuKa data with field measurements to demonstrate snow depth retrieval using Ku- and Ka-band data.
A standardized database of Last Interglacial sea-level indicators in southeast Asia: Records from coral reef terraces in a tectonically complex region
Authors: Maxwell Kathrine , Westphal Hildegard , Rovere Alessio
Published: March 2021

The Last Interglacial (LIG), as well as other warmer periods in the Earth’s geologic history, provides an analogue for predicted warming conditions in the near future. Analysis of sea-level indicators during this period is important in constraining regional drivers of relative sea-level change (RSL) and in modeling future trajectories of sea-level rise. In southeast Asia, several studies have been done to examine LIG sea-level indicators such as coral reef terraces and tidal notches. A synthesis of the state-of-the-art of the LIG RSL indicators in the region, meanwhile, has yet to be done. We reviewed over 50 published works on the LIG RSL indicators in southeast Asia and used the framework of the World Atlas of Last Interglacial Shorelines (WALIS) in building a standardized database of previously published LIG RSL indicators in the region. In total, we identified 38 unique RSL indicators and inserted almost 140 ages in the database. Available data from Indonesia, the Philippines, and East Timor points to variable elevation of sea-level indicators during the LIG highlighting the complex tectonic setting of this region. Variable uplift rates (from as low as 0.02 to as high as 1.1 m/ka) were reported in the study areas echoing various collision and subduction processes influencing these sites. Although several age constraints and elevation measurements have been provided by these studies, more data is still needed to shed more light on the RSL changes in the region. With this effort under the WALIS framework, we hope to identify gaps in the LIG RSL indicators literature in SE Asia and recognize potential areas that can be visited for future work. We also hope that this initiative will help us further understand the different drivers of past sea-level changes in SE Asia and will provide inputs for projections of sea-level change in the future.
Assessment of the dissolved inorganic and organic carbon flux in Cauvery, a tropical river of Southern India.
Authors: Ramesh RamyaPriya , Lakshmanan Elango
Published: March 2021

The carbon fluxes in rivers plays a critical role in the global carbon cycle but its role is always understated. The tropical rivers alone accounts for about 70% of global riverine carbon fluxes due to their large areal extent, varying climatic conditions and land use. Studies on the dissolved carbon fluxes in non-perennial tropical rivers are limited, but it holds much importance as that of perennial rivers. Hence, the present study was carried out with an objective to understand about the inorganic and organic carbon fluxes in a large non-perennial tropical river of Southern India. The samples were collected from 28 locations along the river thrice in a year from 2013-2020 and were analysed for major ions, DIC and DOC. The concentration of DIC in the river water in most of the locations is greater than that of DOC. The DOC concentration is greater at pristine locations thereby decreasing along the flow direction of the river, whereas the DIC concentration increases along the flow direction. The spatial and temporal variability in DOC and DIC concentrations is attributed due to the changes in the rainfall, river flow, climate, lithology, land use patterns, in the catchment. The DIC concentration was found to be majorly governed by silicate and carbonate weathering along with biogenic process, mineralisation and other river process, whereas the primary production, microbial process along with soil organic carbon influences the DOC concentration in the rivers. Thus, this study identifies the sources of DIC and DOC in rivers and the processes which influences the carbon export to the sea.
A hysteretic model for rainfall-runoff of a simplifed catchment 
Authors: Flynn Denis , Roche Warren
Published: March 2021

The soil can be modelled as a porous medium in which the three phases of matter coexist and produce the emergent phenomenon of hysteresis.

Rate-independent hysteresis is a nonlinear phenomenon where the output depends not only on the current input but also the previous history of inputs to the system. In multiphase porous media such as soils, the hysteresis is in the relationship between the soil-moisture content, and the capillary pressure.

In this work, we develop a simplified hysteretic rainfall-runoff model consisting of the following subsystems that capture much of the physics of flow through a slab of soil:

1) A slab of soil where rainfall enters and if enough water is present in the soil, it will subsequently drain into the groundwater reservoir. This part of the model is represent by ODE with a Preisach operator.

2) A runoff component: If the rainfall exceeds the maximum infiltration rate of the soil, the excess will become surface runoff. This part of the model is represented by a series of two hysteretic reservoirs instead of the two linear reservoirs in the literature.

3) A ground water storage and outflow subsystem component: this is also modelled by a hysteretic reservoir. Finally, the outputs from the groundwater output and the overland flow are combined to give the total runoff. We will examine this model and compare it with non-hysteretic case both qualitatively and quantitively.
Global Flood Mapper: Democratising open EO resources for flood mapping
Authors: Tripathy Pratyush , Malladi Teja
Published: March 2021

Climate change has increased the frequency of flood events globally. Floods cause massive loss of life and cause the expenditure of billions of dollars. While it is important to curb floods caused by anthropogenic factors in the first place, it is equally important to reduce the impact in the aftermath of floods. The extent of past flood events is crucial for developing disaster management plans and flood hazard modelling. Due to the lack of capacity and availability of the funds with local officials, many past disasters remain unmapped and the information is just limited to total life loss and damage estimates.

Satellite data has been widely hailed as an alternative to drone and aerial surveys. And recent advances in open Earth Observation (EO) data availability, for instance, the Sentinel-1 SAR data by the European Space Agency (ESA), and cloud processing platforms such as the Google Earth Engine (GEE) have opened unprecedented opportunities for using EO data for hazard and disaster response efforts. Recent literature in the field of EO is witnessing an increasing number of the Sentinel-1 and GEE combination for flood mapping.

In the present work, we demonstrate the utility of a recently developed tool, the Global Flood Mapper (GFM), which is an open GEE application for rapid mapping of flood inundation extent using Sentinel-1 data. GFM uses a pre-flood time period to analyse numerous Sentinel-1 scenes of the same study area, this accounts for seasonal variation and has lesser noise as compared to other methods that use just one pre-flood scene. We map a couple of flood events across the globe to demonstrate the scalability and ease of using GFM. In addition, we analyse the flood hazard vulnerability of the state of Bihar in India using flood extent for the year 2018, 2019 and 2020 by delineating frequently flooding areas. This showcases yet another crucial utility of the GFM tool. GFM can support the flood extent mapping of the past events in addition to the rapid flood mapping of the current events, that could aid researchers and disaster managers for better flood preparedness and response. 

We access GFM through the link available on this public repository: https://github.com/PratyushTripathy/global_flood_mapper
Emerging controls of in-stream uptake at the catchment scale
Authors: Dehaspe Joni , Musolff Andreas
Published: March 2021

Nitrate (NO3-) and phosphate (PO43-) inputs to rivers are high in Germany and Europe following energy and food production demands, which can cause harm to aquatic ecosystems and jeopardize drinking water supplies. It is known that permanent and non-permanent nutrient uptake can retain significant amounts of NO3- and PO43- in river networks, however, there is little knowledge about the mechanistic processes involved and their controlling factors on catchment scales. In this work we apply a data driven analysis using the shape of stable, multi-annual, low frequency concentration-discharge (C-Q) relationships in about 500 German monitoring stations. More specifically, the bending of NO3- C-Q relationship was shown to encode uptake efficiency. We systematically address the effects of light and shading, stream ecological status, land-use, hydrological conditions, stream network configurations and chlorophyll a patterns as potential in-stream processing predictors. This assessment allows us to conclude on dominant controls of NO3- uptake efficiency across a wide range of landscape types.
The impacts of environmental and socioeconomic factors on the non-point source pollution in a small watershed in the Three Gorges Reservoir Area, China
Authors: Deng Jun , Li Zhaoxia
Published: March 2021

Determining the impacts of environmental and socioeconomic factors on nitrogen (N) and phosphorus (P) loss in the watershed is critical to reducing non-point source (NPS) pollution. This paper, we set 13 sampling points in the main stream and tributaries of watershed and sampled every two weeks from 2018 to 2020 to monitor the total nitrogen (TN) and total phosphorus (TP) concentration in the waterbodies. Twenty-six potential influencing factors affecting the nitrogen and phosphorus loss in the watershed were selected. The partial least squares regression (PLSR) was used to determine the relationship between TN and TP concentrations in the watershed and the 26 selected potential influencing factors. The results showed that the mean TN concentrations and mean TP concentrations in the dry season (11.42 mg·L−1 and 0.09 mg·L−1, respectively) were both less than those in the wet season (13.20 mg·L−1 and 0.11mg·L−1, respectively). The optimal PLSR model explained 69.6%, 73.1% and 66.1% of the TN concentration variability, and 65.7%, 79.5% and 67.4% of the TP concentration variability during annual, dry season and wet season, respectively. According to the importance of the variables in the predicted value (VIP), topographic wetness index (TWI), planting structure (PS), interspersion and juxtaposition index (IJI), Orchard land use (OP), nitrogen fertilizer application (NF), per capita income (INCOME) and catchment area (AREA) were the key factors affecting TN concentration, whereas topographic wetness index (TWI), interspersion and juxtaposition index (IJI), population density (POP), slope gradient (SLOPE) and hypsometric integral (HI) were the key controlling factors of TP concentration. In addition, TN concentration was affected by cropland land use (CP) during the dry season and proportion of labor (LABOR) and per capita agricultural land area (ALA) during the wet season. TP concentration was affected by mean patch size (AREA_MN), phosphate fertilizer application (PF) and patch density (PD) during the dry season and residential area (RP) and values during the wet season. This study illustrates the impact of environmental and socioeconomic factors on NPS pollution, and can be used as a guide for effective NPS pollution control and water quality management.
ECLand: an ECMWF land surface modelling platform
Authors: Balsamo Gianpaolo , Boussetta Souhail
Published: March 2021

The ECMWF operational land surface model, based on the Carbon-Hydrology Tiled ECMWF Scheme for Surface Exchanges over Land (CHTESSEL) is the baseline for global weather, climate and environmental applications at ECMWF. In order to expedite its progress and benefit from international collaboration, an ECLand platform has been designed to host advanced and modular schemes. ECLand is paving the way toward a land model that could support a wider range of modelling applications, facilitating global kilometer scales testing as envisaged in the Copernicus and Destination Earth programmes. This presentation introduces the CHTESSEL and its recent new developments that aims at hosting new research applications.

These new improvements touch upon different components of the model: (i) vegetation, (ii) snow, (iii) soil hydrology, (iv) open water/lakes (v) rivers and (vi) urban areas. The developments are evaluated separately with either offline simulations or coupled experiments, depending on their level of operational readiness, illustrating the benchmarking criteria for assessing process fidelity with regards to land surface fluxes and reservoirs involved in water-energy-carbon exchange, and within the Earth system prediction framework, as foreseen to enter upcoming ECMWF operational cycles.

Reference: Souhail Boussetta, Gianpaolo Balsamo*, Anna Agustì-Panareda, Gabriele Arduini, Anton Beljaars, Emanuel Dutra, Glenn Carver, Margarita Choulga, Ioan Hadade, Cinzia Mazzetti, Joaquìn Munõz-Sabater, Joe McNorton, Christel Prudhomme, Patricia De Rosnay, Irina Sandu, Nils Wedi, Dai Yamazaki, Ervin Zsoter, 2021: ECLand: an ECMWF land surface modelling platform, MDPI Atmosphere, (in prep).
0.5 Degree: A Turning point
Authors: Campbell Jayaka , Taylor Michael , Bezanilla-Morlot Arnoldo , Stephenson Tannecia , Centella-Artola Abel , Clarke Leonardo , Stephenson Kimberly
Published: March 2021

Although the Caribbean region is considered amongst the most vulnerable to the impacts of climate and climate change, there are very few regional studies or studies matching the regions small scale and size that evaluate or quantify the impacts of these future changes.  The absence becomes even more stark when the long-term temperature goals (LTTGs) of 1.5°C, 2.0°C and 2.5°C above pre-industrial warming levels are considered. By selecting, validating and downscaling a subset of the Hadley Centre’s 17-member Perturbed Physics Ensemble for the Quantifying Uncertainty in Model Predictions (QUMP) project, future changes for both the LTTGs as well as mid and end of century are evaluated, for the entire Caribbean and its six (6) sub-regional zones. Showing distinct and significant sub-regional variations, on average the Caribbean was found to be 2.1°C (>4°C) warmer and 40% (70%) drier by mid-century (end of century). Analysis of the LTTGS shows that the region surpasses lowest target, 1.5 °C, before the end of the 2020’s and experiences progressive warming that spread equatorward as successive thresholds are attained 2.0°C (2030’s) and 2.5°C (2050´s). The far western, the southern and the eastern Caribbean are found to be up to 50% drier at 1.5°C, with intensifications noted for changes at 2.0°C with a reversal of a wet tendency in the north and central Caribbean. The sub-regional variations that exist shows that although the Caribbean lags the globe in its attainment of the LTTGs some of its six subregions are more comparable to the global than the Caribbean mean with the transition from 1.5°C to 2.0°C seeming to represent a turning point for the Caribbean.
Geoheritage and Potential Geotourism Sites in Spiti Valley, Himachal Pradesh, India
Authors: Krishnanand Krishnanand
Published: March 2021

Geoheritage are those components of geodiversity that are specifically identified as having conservation significance; that have some specific value to human society and therefore ought to be conserved, particularly if they are threatened by human activities and could therefore be lost or damaged. The Spiti valley of Himachal Pradesh, India is unique due to the presence of Tethyan sediments that are exposed and have abundance of fossils that makes it a rich and valuable geoheritage site. The research focuses upon the study of various existing tourist hot spots and potential geoheritage sites. The main objective of the study is to assess the human response (geotourism) to the diversity of existing and potential geoheritage sites in the area. The study is largely based on the field work conducted in the study area between 2014-19 in which data has been collected through structured questionnaire survey, observation and in-depth interviews through field work and SWOT analysis has been done accordingly. The locations of geoheritage sites have been marked using Global positioning System (GPS) and an overlay map has been prepared using Arc Map 10 (GIS software). Overall, the major issue is the lack of geoconservation policy and inaccessibility which needs to be addressed with better management efforts such as Fossil Park or geo-park establishment.

Key words: Geoheritage, Geotourism, Spiti Valley, Potential Geoheritage Sites, Fossil Park
Observed variability of monsoon blooms in the north-central Arabian Sea and its implication on oxygen concentration: A Bio-Argo study
Authors: Mathew Teesha
Published: March 2021

The central Arabian Sea (CAS) is productive during both the summer and winter monsoons owing to different physical processes. We analysed four years (2013-2016) record of chlorophyll and dissolved oxygen (DO) concentration from a Bio-Argo float deployed in this region. Though the surface blooms were observed during both the monsoons and sub-surface chlorophyll was also persistently observed, the intensity and duration of the bloom have been decreasing over the past few years. Also, the winter blooms were more prominent compared to the summer bloom in the study region. Our analysis shows that the observed inter-annual variability in the summer bloom can be attributed to the variability in wind speed, oceanic stratification and advection of nutrient rich water from the western Arabian Sea. During both the monsoons, stratification played an important role in reducing the productivity in recent years. We also found that during the winter monsoon, the upwelling Rossby wave propagating from the west coast of India influenced productivity as north as 15ºN. The chlorophyll data from Bio-Argo float shows that the total surface chlorophyll concentration has been decreasing during the study period. Consequently the DO concentration has also been decreased. An increase in the deeper water is speculated to be due to the  decrease in surface productivity. This is in contradiction to the previous studies on intensification of Arabian Sea OMZ. Also, in the event of recent reports on decreasing trend in productivity in the Arabian Sea, the present study provides new insights on the possible effect of declining productivity on the DO concentration under the climate change regime.
Fluid mixing and mineralization along faults – the role of stable and traveling reactive zones
Authors: Koehn Daniel , Mullen Gary , Boyce Adrian , Ulrich Kelka , Toussaint Renaud
Published: March 2021

Fluid mixing is one of the important ore-forming processes for hydrothermal mineralization. A common hypothesis envisages hot metal-bearing fluids entering rocks that contain brines derived from paleo-seawater. Upwelling of pressurized hydrothermal fluids may occur along permeable faults or fracture systems along fluid pressure gradients. When the upwelling- and pore fluids mix, the conditions for ore-precipitation are met for instance by varying pH, temperature, or redox-conditions. This would be reflected best by changes in the saturation states of the respective mineral phases.

However, how does this process work in detail? How are the two fluids moving, where are they are meeting, how are they mixing and what minerals are precipitating? In order to study such a system, we link a transport model in the software ELLE with the IPHREEQC library of the USGS. We investigate the case of two fluids, a pore fluid representing paleo-seawater and a hot metal-rich fluid that enters the system at high fluid overpressure. As an initial condition, the pore fluid is equilibrated with different mineral phases reflecting different lithologies with varying permeabilities. Temperature as well as multi-components in the system are advecting along pressure gradients as a function of the local Darcy velocity that is calculated as the influx of a compressible fluid initially entering the system and subsequently leading to a flux through the system. In addition, the different species are diffusing as a function of the timescales set by the pressure diffusion into the system. IPHREEQC then calculates the fluid properties and mineral saturation states for every node in the system.

We show that a reactive wave develops between the two fluids, pore matrix, and infiltrating fluid. The incoming fluid pushes the pore fluid out of the system and the mixing process is mainly governed by diffusion. Depending on the time scales involved, minerals will preferably precipitate between the fluids in relatively “quiet” domains where the reactive zones prevail for an extended time. An example are fault walls where the reactive zone is stable for a longer time, whereas it is moving relatively fast along the faults. We discuss the implications of our observations with respect to low temperature ore deposits, present a first model of reactive domain development in a two-fluid system, and compare the results obtained by utilizing different thermodynamic databases.
Permian rifting and detachment faults and their role in Alpine collisional tectonics
Authors: Froitzheim Nikolaus , Klug Linus
Published: March 2021

The Permian was a time of strong crustal extension in the area of the later-formed Alpine orogen. This involved extensional detachment faulting and the formation of metamorphic core complexes. We describe (1) an area in the Southern Alps (Valsassina, Orobic chain) where a metamorphic core complex and detachment fault have been preserved and only moderately overprinted by Alpine collisional shortening, and (2) an area in the Austroalpine (Schneeberg) where Alpine deformation and metamorphism are intense but a Permian low-angle normal fault is reconstructed from the present-day tectonometamorphic setting. In the Southern Alps case, the Grassi Detachment Fault represents a low-angle detachment capping a metamorphic core complex in the footwall which was affected by upward‐increasing, top‐to‐the‐southeast mylonitization. Two granitoid intrusions occur in the core complex, c. 289 Ma and c. 287 Ma, the older of which was syn-tectonic with respect to the extensional mylonites (Pohl, Froitzheim, et al., 2018, Tectonics). Consequently, detachment‐related mylonitic shearing took place during the Early Permian and ended at ~288 Ma, but kinematically coherent brittle faulting continued. Considering 30° anticlockwise rotation of the Southern Alps since Early Permian, the extension direction of the Grassi Detachment Fault was originally ~N‐S and the sense of transport top-South. In this area, there is no evidence of Permian strike-slip faulting but only of extension. In the Schneeberg area of the Austroalpine, a unit of Early Paleozoic metasediments with only Eoalpine (Cretaceous) garnet, the Schneeberg Complex, overlies units with two-phased (Variscan plus Eoalpine) garnet both to the North (Ötztal Complex) and to the South (Texel Complex). The basal contact of the Schneeberg Complex was active as a north-directed thrust during the Eoalpine orogeny. It reactivated a pre-existing, post-Variscan but pre-Mesozoic, i.e. Permian low-angle normal fault. This normal fault had emplaced the Schneeberg Complex with only low Variscan metamorphism (no Variscan garnet) on an amphibolite-facies metamorphic Variscan basement. The original normal fault dipped south or southeast, like the Grassi detachment in the Southern Alps. As the most deeply subducted units of the Eoalpine orogen (e.g. Koralpe, Saualpe, Pohorje) are also the ones showing the strongest Permian rift-related magmatism, we hypothesize that the Eoalpine subduction was localized in a deep Permian rift system within continental crust.
Magnetite (U-Th-Sm)/He dating: analytical challenges and application
Authors: Corre Marianna , Lanson Martine , Agranier Arnaud , Schwartz Stephane , Brunet Fabrice , Gautheron Cécile , Pinna Rosella
Published: March 2021

Magnetite (U-Th-Sm)/He dating method has a strong geodynamic significance, since it provides geochronological constraints on serpentinization episodes, which are associated to important geological processes such as ophiolite obductions, subduction zones, transform faults and fluid circulations. Although helium content that range from 0.1 pmol/g to 20 pmol/g can routinely be measured, the application of this dating technique however is still limited due to major analytical obstacles. The dissolution of a single magnetite crystal and the measurement of the U, Th and Sm present at the ppb level in the corresponding solution, remains highly challenging, especially because of the absence of magnetite standard. In order to overcome these analytical issues, two strategies have been followed, and tested on magnetite from high-pressure rocks from the Western Alps (Schwartz et al., 2020). Firstly, we purified U, Th and Sm (removing Fe and other major elements) using ion exchange columns in order to analyze samples, using smaller dilution. Secondly, we performed in-situ analyzes by laser-ablation-ICPMS. Since no solid magnetite certified standard is yet available, we synthetized our own by precipitating magnetite nanocrystals. The first quantitative results obtained by LA-ICP-MS using this synthetic material along with international glass standards, are promising. The laser-ablation technique overcomes the analytical difficulties related to sample dissolution and purification. It thus opens the path to the dating of magnetite (and also spinels) in various ultramafic rocks such as mantle xenoliths or serpentinized peridotites in ophiolites.

Schwartz S., Gautheron C., Ketcham R.A., Brunet F., Corre M., Agranier A., Pinna-Jamme R., Haurine F., Monvoin G., Riel N., 2020, Unraveling the exhumation history of high-press ure ophiolites using magnetite (U-Th-Sm)/He thermochronometry. Earth and Planetary Science Letters 543 (2020) 116359.
German Near-Real Time Ensemble Hydroclimate Forecasting System
Authors: Najafi Husain , Thober Stephan , Rakovec Oldrich , Shrestha Pallav Kumar , Samaniego-Eguiguren Luis
Published: March 2021

Helmholtz Centres are developing a research infrastructure in Germany to investigate the interactions of short-term events and long-term trends across Earth compartments under the Modular Observation Solutions for Earth System initiate (MOSES- https://www.ufz.de/moses/). A near-real time hydroclimate forecasting system at sub-seasonal to seasonal time range (HS2S) is developed for MOSES to provide tailored information for early warning of extreme events. 

Here, we introduce two components of the HS2S which benefits from operational forecasts provided by the European Center for Medium-range Weather Forecast (ECMWF). The first component is weekly averaged forecasts of two atmospheric variables (total precipitation and maximum air temperature) which are bias corrected using a trend-preserving approach. The second component is German hydrological forecasting system. We use the mesoscale Hydrological Model (mHM- https://www.ufz.de/mhm) for generating hydrological initial conditions and ensemble forecasting. The same approach by German Drought Monitor (www.ufz.de/duerremonitor) is applied to interpolate near-real time in-situ observations from the German Meteorological Service (DWD) into 1-km grids. Then 51 real-time atmospheric daily ensemble forecasts from ECMWF ensemble extended product are bias corrected to generate of soil moisture and streamflow forecasts up to 30-day in advance. By post-processing mHM ensemble forecasts, an overview of drought conditions for the next 30-days horizon is disseminated online over Germany (https://www.ufz.de/moses/index.php?en=47304). Hydroclimate forecast are updated operationally twice a week to support MOSES event-driven campaigns for flood, drought and heat waves and to understand the predictability and skill of near-real time hydroclimate forecasts in Central Europe based on the state-of-the-art models and tools.  