bluuebunny/crossref_metadata_2025 huggingface dataset:
Progress on the development of innovative, floating, biodegradable radio- probes for atmospheric monitoring inside warm clouds
Authors: Paredes Miryam , Abdunabiev Shahbozbek , Allegretti Marco , Perona Giovanni , Tordella Daniela , Pasero Eros , Canavero Flavio , Merlone Andrea , Musacchio Chiara
Published: March 2020

Characterization of clouds is still a challenging task for weather forecasting and climate modeling. This is because clouds depend on interdisciplinary natural processes, ranging from the micrometer scale, where particles and droplets collide, to the thousand-of-meters scale of airflow dynamics. Turbulence has an important role in cloud formation and rain initiation since it helps rain droplets to evolve through coalescence and collision processes. Unfortunately, the effects of turbulence mechanisms are not yet well understood and there remains a need for further clarification.

In an attempt to address these knowledge gaps, this work presents the advances of an experimental method for measuring in-situ the influence of turbulence in cloud formation and producing an infield cloud Lagrangian dataset by means of the development of ultra-light bio- compatible radio-probes. With a target weight of less than 20 grams, these innovative devices are carefully designed to float and passively track small-scale turbulence fluctuations in warm clouds and neighboring air. Each mini radio-probe embeds a set of compact size microprocessors, controllers and sensors for the measurement of atmospheric parameters inside clouds (e.g. velocity, acceleration, vorticity, pressure, temperature, humidity) after been released into the atmosphere. To reach a buoyancy force equal to the weight of the system, the bio balloons containing the electronics are appropriately filled with a mixture of helium gas and air. During the flight, the smart radio-probes acquire, pre-process, store, arrange and transmit the obtained data to different receiving and ground stations located on earth through a dedicated radio transmission link. Due to the radio-probes’ physical constrains and the environmental conditions that can be found inside warm clouds, a power-saving and long-range wireless communication technology has been selected and tested.

The development of the first operational prototypes for both, the radio-probes and the receiving stations, are presented together with results of the first measurement experiments both, in laboratory and field campaign.
Airborne Atmospheric Measurements with the mini Max Planck CloudKite
Authors: Schröder Marcel , Nordsiek Freja , Schlenczek Oliver , Ibanez Landeta Antonio , Bodenschatz Eberhard , Bagheri Gholamhossein
Published: March 2020

Clouds play a key role in the energy balance of the Earth's atmosphere and its radiation budget. The lack of detailed understanding of clouds is one of the reasons for the uncertainties in weather forecasting and climate modelling. The dynamics of clouds extend over a wide range of spatial and temporal scales from micrometers to km and milliseconds to hours. Besides Plinian volcanic eruptions, clouds show the highest turbulence level on earth. The multiscale properties of the turbulent flow in combination with moisture and temperature transport, phase transitions, and inertial particle dynamics present a challenge for modelling and parameterization.  Here we use a specially developed airborne platform, the Mini-Max-Planck-CloudKite (Mini-MPCK), to measure meteorological and cloud microphysical properties with high spatial and temporal resolution. The mini-MPCK is a 75 qm helium-filled balloon kite carrying a tether-mounted instrument for measuring atmospheric state parameters, and the density and size distribution of cloud particles. We will report on measurements from the trade wind region obtained during the EUREC4A campaign in Jan-Feb 2020.
Uranium phosphate mineral adsorption to newly isolated fungus Cladosporium sp. strain F1
Authors: Lee Jisu , Hur Hor-Gil
Published: March 2020

It is necessary to develop environmentally benign methods for removing uranium from various environments due to its high toxicity and radioactivity. Among the methods, we used fungal biosoprtion using newly isolated Cladosporium sp. strain F1. Extensive absorption of presynthesized nanoplates of uranium-phosphate minerals was observed on the hyphae of the Cladosporium sp. strain F1. In addition, once soluble UO22+ species was added to the culture of Cladosporium sp. strain F1, uranium mineral plates were also observed on the surface of the fungus hyphae over a range of pH. This was confirmed by EDX analyses, and SEM, AFM, and thin sectional TEM image analyses. The maximum biosorption capacity of uranyl ions was 74.3 mg g⁻¹ at pH 6.0. In general, biosorption capacity of Cladosporium sp. strain F1 was better than that of Aspergillus niger strain to uranium minerals. In conclusion, this study showed that the newly isolated fungus Cladosporium sp. strain F1 could be a cost-effective and environmentally friendly biosorbent to remove toxic uranium from aqueous environments.
Seasonal to interannual variations of wind forcing in the Peruvian upwelling system
Authors: Yari Sadegh , Mohrholz Volker
Published: March 2020

The Humboldt (Peruvian) Upwelling System (HUS) is the most productive among the main Eastern Boundary Upwelling Systems (EBUS), namely California, North West Africa, Benguela and itself. In spite of comparable upwelling intensity its fisheries production exceeds that of the other upwelling systems considerably (Chavez and Messie 2009). Wind is the major driving force of the coastal and curl driven upwelling, that controlls the nutrient supply from the deep water pool to the euphotic surface layer. Strength, spatial and temporal variability of the wind forcing are subjected to seasonal and interannual changes. The core of this study is describe the wind driven upwelling cells in the Peruvian coastal area in detail using long-term data which is not well understood. A better understanding of the state and dynamics of HUS seems essential for fututre regional climate predictions. ASCAT wind stress data for the period of 11 years (2008-2018) is analyzed to assess the spatio-temporal variations of the wind stress field, coastal upwelling and Ekman pumping along the Peruvian coast. The meridional component of wind stress off the peruvian coast, which is the main driver of offshore transport, has been marginally inensified over the entire priod. However, a high level of interannual variability is evident. The El-Niño years show anomalously high wind stress and associated Ekman transoprt. Our results indicate that the southern sector is more influenced by ENSO cycle than the northern sector. Additionally, a strong seasonality in the wind stress is observed. During the austral summer (December-February) the wind stress show the minimum value while the high values are observed in July-September.
Developing reservoir sediment ceramsite as a novel growing medium: II pot experiments
Authors: Chu Yi-Hao , Liu Yu-Hsiang , Cheng Chih-Hsin
Published: March 2020

Reservoir sedimentation is an environmental issue that can be substantially detrimental to the lifetime of reservoirs. In this study, we tried to develop the ceramsite made from reservoir sediment and used it as a growing medium. Different from the traditional method, we sintered the material at a lower temperature (800oC) under an anaerobic atmosphere. The low-temperature ceramsite might provide higher water and nutrient retention capacity compared to the high-temperature ceramsite. The anaerobic atmosphere could preserve organic matter as biochar, which may offer better water and nutrient retention capacity as well. Pot experiments using the low-temperature ceramsite along with commercial high-temperature ceramsite (1200oC) and lava rock as the growing media were conducted. Two species Tagetes erecta and Melissa officinalis under the full water supply and limited water supply (100 ml per pot per week) conditions were planted. The results showed that the plants grown in low-temperature/anaerobic ceramsite had the best agronomic performance. Under the full water supply, the shoot height was higher in the low-temperature ceramsite than other treatments. The height was 45.8 - 48.2 vs. 16.28 - 18.73 cm in Tagetes erecta and 15.1 - 18 vs. 7.65 - 9.4 cm in Melissa officinalis. The dry weight in the low-temperature ceramsite was 5-10 times higher than those in other treatments after four months of growth. Under the water-limited condition, the plants are grown in the low-temperature ceramsite still performed better on shoot height (Tagetes erecta: 25.05 - 30.88 cm and Melissa officinalis: 14.08 – 14.75 cm) and dry weight (Tagetes erecta: 1.03 - 1.5 g and  Melissa officinalis: 0.67 – 0.89 g). The results suggest that the low-temperature/anaerobic ceramsite has the potential using as a novel growing medium and a new option for treating reservoir sediment.

 
A Late Miocene terrestrial temperature history for the northeastern Tibetan Plateau’s period of tectonic expansion
Authors: Bai Yan , Chen Chihao , Fang Xiaomin , Guo Haichao , Meng Qaingquan , Zhang Weilin
Published: March 2020

During the Late Miocene, the climate patterns and ecosystems of continental land masses experienced crucial transitions, but whether the principal driver was regional tectonic forcing or a decline in CO2 concentrations remains debated. Terrestrial paleotemperature records from tectonically active regions can conserve both paleoaltitudinal and global temperature changes which have occurred as a result of fluctuations in the levels of CO2. However, high-quality quantitative data remain scarce, due to the lack of terrestrial paleotemperature reconstruction tools and well-dated continuous stratigraphic sequences. Based on a continuous sedimentary sequence with high precision dating from ~54-4.8 Ma in Xining Basin, northeastern Tibetan Plateau established, and evaluation of the potentiality of the branched glycerol dialkyl glycerol tetraethers (brGDGTs) in paleotemperature/paleoelevation reconstruction in Tibetan Plateau by our group, we present a terrestrial paleotemperature record spanning ~12.7-5.2 Ma based on tetraether lipids extracted from the northeastern Tibetan Plateau. Our results reveal a sharp cooling (~8°C) during ~10.5-8 Ma, asynchronous with minor fluctuations in global sea temperatures, suggesting a rapid tectonic uplift of ~1 km in extent. This event appears consistent with the simultaneous aridification and transitions of ecosystems experienced in adjacent regions. Moreover, the amplitude of the cooling over land is less than that which occurred over the ocean during the CO2-dominated Late Miocene cooling event (~7-5.4 Ma). We therefore concluded that tectonic forcing, rather than a decline in CO2 levels, most likely dominated continental climate patterns and ecosystem transitions during the Late Miocene.
Six Underground Laboratories (ULs) Participating in the Baltic Sea Underground Innovation Network
Authors: Ohlsson Mats , Joutsenvaara Jari , Laaksoharju Marcus , Niinikoski Eija-Riitta
Published: March 2020

Baltic Sea Underground Innovation Network, BSUIN, consist of six participating Underground Laboratories (ULs) located in countries surrounding the Baltic Sea [http://bsuin.eu]. The BSUIN is a three-year project funded by the EU Interreg Baltic Sea Region Programme. 

The aim of the BSUIN project is that the participating ULs will find new or expand the current use of underground laboratories to enhance the power of innovation and regional development. The project focus on the characterisation of the geological and technical settings of the ULs, health and safety issues, and various aspects to build and support innovation and the formation of a permanent network of Underground Laboratories.

The BSUIN ULs consist of old mines or purpose-built underground facilities. The ULs are used for research concerning e.g. environmental, geoenergy, geotechnology, physics, material science and natural sciences. Education, events, tourism and farming is also activities hosted by ULs.

We will present the underground laboratories of the BSUIN network:

Äspö Hard Rock Laboratory, Oskarshamn, Sweden [http://www.skb.com/research-and-technology/laboratories/the-aspo-hard-rock-laboratory/],

Forschungs- und Lehrbergwerk - Research and Eduction Mine "Reiche Zeche", Freiberg, Germany [http://www.besucherbergwerk-freiberg.de/],

Callio Lab in Pyhäsalmi mine, Pyhäjärvi, Finland [calliolab.com/callio-lab],

KGHM S.A. mining company, Poland, together with their research organisation KGHM CUPRUM which proposes the construction of ULs located in one of the KGHM’s deep copper [http://www.cuprum.wroc.pl/],

The Low-Background underground laboratory of Khlopin Institute, St Petersburg, Russia [http://www.khlopin.ru/en/],

Ruskeala Marble quarry and Geopark in Sortavala, Karelia, Russia. [http://ruskeala.info/en].
A Consistent Thermo-Compositional Model of the South American Cratonic Lithosphere from Integrated Inversion of Gravity and Seismic Data
Authors: Finger Nils-Peter , Kaban Mikhail , Tesauro Magdala , Haeger Carina , Mooney Walter , Thomas Maik
Published: March 2020

We present an integrated model of the cratonic lithosphere of South America. Gravity and seismic data were jointly analyzed using mineral physics constraints to assess state and evolution of the cratonic roots in South America in terms of temperature, density and composition. At the cratons, our model enables separation of two counteracting effects: the increased density due to cooling with age and decreased density due to depletion of iron. The depletion of iron can be described by the Mg# which gives the partition of Mg2+ among the double positive ions. A new crustal model (including depth to the Moho) based on existing seismic data was used to correct the gravity field for crustal effects and to uncover the gravity signal of the mantle. In addition, residual topography was calculated as a measure of the part of topography not balanced by the crustal density variations and depth to the Moho. Temperatures within the lithospheric mantle were estimated based on seismic velocities and mineral physics equations, initially assuming a juvenile mantle composition (Mg# of 89). The residual fields were corrected for the respective effects. In the following inversion of residual gravity and topography, we have determined additional density variations which can be interpreted as compositional ones. Furthermore, these results were employed to recompute the upper mantle temperatures taking into account possible compositional changes in the cratonic roots. In this iterative procedure, a consistent thermo-compositional model of the upper mantle has been obtained. Negative compositional density variations imply depletion of iron, leading to higher Mg#s. The highest depletion occurs in the Amazonas and São Francisco Cratons reaching values in the cratons’ centers of up to 90 (Mg#). At the same time, their centers show very low temperatures, down to 600° C in the depth of 100 km. They stay below 1300° C even at a depth of 200 km, indicating deep lithospheric roots. Higher temperatures are found in the Andean forelands and along the Trans-Brasiliano-Lineament (TBL), dividing the Amazonas and São Francisco Cratons. Compositional density variations yield smaller to no amounts of depletion in the Amazonas Craton below a depth of 100 km. The São Francisco Craton still shows depletion in 200 km depth (Mg# up to 89.5). Slightly negative compositional density variations southwest of the São Francisco Craton also exist at depths up to 200 km, indicating the Paranapanema cratonic fragment.
Deccan Volcanism or the Chicxulub Impact: The Chicken or Egg Question
Authors: Keller Gerta
Published: March 2020

The Cretaceous–Paleogene boundary (KTB or KPB) mass extinction is primarily known for the
demise of the dinosaurs, the Chicxulub impact, and the rancorous forty-year-old controversy
over the cause of this mass extinction. For the first 30 years, the controversy primarily revolved
around the age of the impact claimed as precisely KTB based on the assumption that it caused
the mass extinction. The iridium (Ir) anomaly at the KTB was claimed proof of the asteroid
impact, but no Ir was ever associated with impact evidence and recent findings reveal no
extraterrestrial component in PGEs or the KTB Ir anomaly. Impact melt rock glass spherules are
also claimed as indisputable evidence of the KTB age impact, but such spherule layers are
commonly reworked from the primary (oldest) layer in late Maastrichtian, KTB and Danian
sediments; thus only the oldest impact spherule layer documented near the base of zone CF1
~200 ky below the KTB can approximate the impact’s age. Similarly, the impact breccia in the
Chicxulub impact crater predates the KTB. The best age derived from Ar/Ar dating of impact
glass spherules is within 200 ky of the KTB and thus no evidence for the KTB age. All evidence
strongly suggests the Chicxulub impact most likely predates the mass extinction ~ 200 ky and
played no role in it.
Deccan volcanism (LIP) was dismissed as potential cause or even contributor to the KTB mass
extinction despite the fact that all other mass extinctions are associated with Large Igneous
Province (LIP) volcanism but none with an asteroid impact. During the last decade, Deccan
volcanism gained credence based on a succession of discoveries: 1) the mass extinction in
between the longest Deccan lava flows across India; 2) high-precision dating of the entire
sequence of Deccan volcanism based on UPb zircon dating; 3) recognition of four distinct
eruption pulses all related to global climate warming with the largest pulse beginning 20 ky prior
to and ending at the KTB; 4) Identifying the climate link to Deccan volcanism based on age
dating and mercury from Deccan eruptions in marine sediments; and 5) Identifying the KTB
mass extinction directly related to the major Deccan eruption pulse, hyperthermal warming and
ocean acidification all linked to global mercury fallout from Deccan eruptions in marine
sediments. Despite this remarkable culmination of evidence, the controversy continues with
impact proponents arguing that Deccan volcanism didn’t exist at the KTB – the impact was the
sole cause.
Development of magnetic nano-geocomposite for groundwater and leachate treatment: A Landfill Management Perspective
Authors: Pradhan Nivedita , Kumar Manish
Published: March 2020

Landfill leachate, a highly contaminated percolating effluent can cause a considerable threat to human as well as environmental health. We developed a novel nano composite using the polymer encapsulated magnetic geopolymer for efficient removal of multi contaminants (As, Zn, Fe, Co, Cu, Ni, Pb, F, NO 3 - , and PO 4 3- ) present in the landfill leachate and groundwater of the Pirana solid waste dumping site, Ahmedabad, Gujarat. A series of batch and column sorption experiments were carried out to find the best-operating conditions for optimum removal efficiency. Results revealed that in the range of 50-60% of multi-contaminant removal is possible using the newly developed adsorbent which has high surface area as well as mixed functional groups for the removal of both cationic (Zn, Fe, Co, Cu, Ni, and Pb) and anionic (F, NO 3 - , and PO 4 3- ) contaminants present in the leachate. Batch study shows that both physical and chemical sorption are equally operational and multilayer removal following the Freundlich isotherms predominantly. The batch test mimics the equilibrium condition only. The study recommends column study under different follow conditions using leachate and groundwater, followed by a regeneration study for its reusability and development of the field implementation schemes. The future research is required to address the decontamination of emerging contaminants like pharmaceuticals, pesticides and fertilizers, industrial additives and antibacterial agents.
Asymmetric friction effects in surface interaction
Authors: Wong Rui Xiang
Published: March 2020

In this study, surface contact involving sections with symmetric and asymmetric friction (different magnitudes of friction are encountered when moving in opposite direction) is considered. The asymmetric friction phenomenon considered here is created when blocks of anisotropic material with symmetric axis inclined to the contact area moves in a constraint environment. Bafekrpour et al. (2015) have shown this arrangement can create high levels of asymmetric friction by coupling shear and normal forces. We consider a spring- blocks model of the type proposed by Burridge and Knopoff (1967): multiple blocks – some blocks with asymmetric friction property and others with symmetric friction property – connected by springs. Each of these blocks are connected by a spring to a driving block. Two types motion for the driving block are considered: moving at constant velocity and constant velocity with an oscillation. Parametric analysis has been conducted to compare the difference in dynamics when comparing surface interaction involving only symmetric friction blocks to different combinations of asymmetric and symmetric friction blocks. We show that threshold for instability/motion can be controlled by the proportion of asymmetric friction section present in the system and the magnitude of friction involved in the asymmetric friction section. The characteristic of the system’s motion is also shown to be affected by the arrangement asymmetric and symmetric friction sections.

Bafekrpour, E., A.V. Dyskin, E. Pasternak, A. Molotnikov and Y. Estrin (2015), Internally architectured materials with directionally asymmetric friction. Scientific Reports, 5, Article 10732.

Burridge, R. and L. Knopoff, 1967. Model and theoretical seismicity. Bulletin of the Seismological Society of America, 57(3) 341-371.
Comparing natural hazard and risk representations in a transboundary area to enhance civil protection international cooperation
Authors: Zambrini Federica , Ambrosi Christian , Bignami Daniele F. , Boschini Ilaria , Czerski Dorota , De Pedrini Alessandro , Menduni Giovanni , Pozzoni Maurizio , Sansone Tommaso L.
Published: March 2020

Each country has its own way to manage the civil protection issue and to define hazard and risk. However, in case of transboundary events, it is crucial that people in charge of the emergency management can quickly understand the other nation instruments, for an effective comprehension, communication and optimal collaboration.

The GESTISCO project (Gestione delle emergenze Senza Confini – emergencies’ management without borders), funded in the framework of the “INTERREG Italia – Svizzera” initiative, aims to promote the capability of Lombardy Region (Italy) and the Ticino Canton (Switzerland) to manage risk scenarios involving both countries together. With this work, we present results of one of the project activities: to compare methods to define natural hazard and risk, understand and underline the differences in the mapping method and visualization, and find ways to help the operators and technicians of both countries in reading and interpreting the representations concerning flood and mass movements hazard.

The activity began with a wide phase of comparison, undertaken from a legislative point of view, to understand the origin and purpose of the maps in both countries’ regulations. From a technical perspective, it was important to be aware of the differences in methods and to understand the reasons behind the inconsistencies. Finally, the data visualization on the maps was also compared, in order to understand the possible reading difficulties for people involved in the risk management and to identify strategies to overcome them.

The next step of the project is the translation of the results of the performed analysis into some practical digital instruments that can easily allow to manage transboundary events, helping the operators in reading and understanding the scenario occurring across the border.
Abrupt changes in wave climate of regional seas caused by large-scale atmospheric forcing and teleconnections
Authors: Kudryavtseva Nadia
Published: March 2020

Climate warming is expected to change the functioning of regional seas substantially. However, it is still an open question how the global climate processes will affect in the future the regional seas, their wave climate, changes in the storm surges and, consequently, the coastal erosion, flooding risks, and coastal communities. In this study, we perform a detailed analysis of the wave climate of the Baltic Sea and the Caspian Sea based on the multi-mission satellite altimetry data in 1990 – 2017. The dataset of significant wave heights (SWH) from ten satellites was cross-validated against regional in situ buoy and echosounder measurements. In the Caspian Sea, due to the limited availability of the in-situ measurements, the satellite data were validated with visual wave measurements. After correction for systematic differences, the visual observations showed excellent correspondence with monthly averaged satellite data with a typical root mean square difference of 0.06 m. Even though several satellite pairs (ENVISAT/JASON-1, SARAL/JASON-2, ERS-1/TOPEX) exhibit substantial mutual temporal drift, and calm wave conditions are ignored, the overall picture is very consistent. The averaged over the whole basin annual mean SWH in the Baltic Sea shows an increase of 0.005 m/yr but no significant trend is detected in the Caspian Sea.

Interestingly, in both Baltic and Caspian seas, changes in the average SWH exhibit a strong spatial pattern. In the Baltic Sea, a meridional pattern is detected: an increase in the central and western parts of the sea and a decrease in the eastern part. This pattern has a timescale of ~13 yr. We also found a faster-varying region in the Baltic Proper where trends in the wave heights experience abrupt changes with a timescale of 3 years and show a strong relation to changes in the North Atlantic Oscillation. In the Caspian Sea, the wave height decreased by 0.019 ± 0.007 m/yr in the eastern segment of the central basin and by 0.04 ± 0.04 m/yr in the western segment of the southern basin when the other parts showed an increase of wave heights. These changes can be explained by an increase in the frequency of westerly winds at the expense of southerly winds. Analysing the changes in the atmospheric forcing we found that there is a cyclic behaviour with a timescale of ~12 years which result in abrupt changes in the wave climate every 12 years, causing the trends in different regions to reverse its sign.

We demonstrate that the impact on the coast and coastal community is caused by a complex chain of events, starting from changes in the wind direction due to large-scale atmospheric variability and atmospheric teleconnections, which create abrupt shifts in the wave climate of regional seas. We discuss that regional seas have a different response to the changing climate compared to the open ocean condition, which can lead to accelerated coastal erosion and a higher risk of flooding.
AQUACOSM-plus: an International Network for Experimental Mesocosm Studies Supporting Experimental Studies of Aquatic-Terrestrial Coupling
Authors: Nejstgaard Jens C , Berger Stella , Makower Katharina , Magiopoulos Iordanis
Published: March 2020

Although processes in aquatic systems are closely connected to the terrestrial environment, these environments are often studied separately. We argue that for a better understanding of both aquatic and terrestrial ecosystems a combination of long-term data from connected environments, coupled with experimental ecosystem-scale experiments, have a greater potential for successful model testing and development of predictive concepts, than using only long-term data (without experiments) from separate systems. This talk will present the new EU-funded RI-project AQUACOSM-plus (www.aquacosm.eu, 2020-2024) that offers access to >50 research facilities across the EU and is linked to world-wide cooperation through the MESOCOSM.EU portal, a virtual network of >100 research facilities. Both networks include mesocosm facilities in all aquatic systems, including rivers, ponds, lakes, estuaries and marine systems – offering unique opportunities to conduct ecosystem-scale experimental studies of relevance to aquatic-terrestrial coupling. This network of research facilities can be used for large-scale process-based studies to test models based on trend or response observations from long-term-data, in order to understand underlying mechanisms of ecosystem functioning relating to the present global Grand Challenges (climate change, biodiversity loss, eutrophication, emerging pollutants, etc.). Interested parties are also welcome to suggest other uses of these research facilities, such as conducting ecosystem solution-based experiments to enable effective management in aquatic ecosystems. The network will fund access to >10.000 days for a wide range of external users, including scientists, students, industry and developers, from the whole world.
GGOS Bureau of Networks and Observations: Network Infrastructure and Related Activities
Authors: Noll Carey , Pearlman Michael , Behrend Dirk , Craddock Allison , Pavlis Erricos , Saunier Jérôme , Bradshaw Elizabeth , Barzaghi Riccardo , Thaller Daniela , Maennel Benjamin , Hippenstiel Ryan , Pail Roland , Brown Nicholas
Published: March 2020

The GGOS Bureau of Networks and Observations works with the IAG Services (IVS, ILRS, IGS, IDS, IGFS, and PSMSL) to advocate for the expansion and upgrade of space geodesy networks for the maintenance and improvement of the reference frame and other applications, as well as for the integration with other techniques, including absolute gravity and sea level measurements from tide gauges. New sites are being established following the GGOS concept of “core” and co-location sites, and new technologies are being implemented to enhance performance in data yield as well as accuracy. The Bureau continues to meet with organizations to discuss possibilities, including partnerships, for new and expanded participation. The GGOS Network continues to grow as new stations join every year.

The Bureau holds meetings frequently, providing the opportunity for representatives from the services to meet and share progress and plans, and to discuss issues of common interest. It also monitors the status and projects the evolution of the network based on information from the current and expected future participants. Of particular interest at the moment is the integration of gravity and tide gauge networks and the forthcoming establishment of the new absolute gravity reference frame. 

The IAG Committees and Joint Working Groups play an essential role in the Bureau activity. The Standing Committee on Performance Simulations and Architectural Trade-offs (PLATO) uses simulation and analysis techniques to project future network capability and to examine trade-off options. The Committee on Data and Information is working on a strategy for a GGOS metadata system for data products and a more comprehensive long-term plan for an all-inclusive system. The Committee on Satellite Missions is working to enhance communication with the space missions, to advocate for missions that support GGOS goals and to enhance ground systems support. The IERS Working Group on Site Survey and Co-location (also participating in the Bureau) is working to enhance standardization in procedures, outreach and to encourage new survey groups to participate and improve procedures to determine systems’ reference points, a crucial aid in the detection of technique-specific systematic errors.
 
We will give a brief update on the status and projection of the network infrastructure of the next several years, and the progress and plans of the Committees/Working Group in their critical role in enhancing data product quality and accessibility to the users.   
Development of early warning system for linear engineering - a case study on highway in Sichuan, China
Authors: Xiao Ruihua
Published: March 2020

For the recent years, highway safety control under extreme natural hazards in China has been facing critical challenges because of the latest extreme climates. Highway is a typical linear project, and neither the traditional single landslide monitoring and early warning model entirely dependent on displacement data, nor the regional meteorological early warning model entirely dependent on rainfall intensity and duration are suitable for it. In order to develop an efficient early warning system for highway safety, the authors have developed an early warning method based on both monitoring data obtained by GNSS and Crack meter, and meteorological data obtained by Radar. This early-warning system is not each of the local landslide early warning systems (Lo-LEWSs) or the territorial landslide early warning systems (Te-LEWSs), but a new system combining both of them. In this system, the minimum warning element is defined as the slope unit which can connect a single slope to the regional ones. By mapping the regional meteorological warning results to each of the slope units, and extending the warning results of the single landslides to the similar slope units, we can realize the organic combination of the two warning methods. It is hopeful to improve the hazard prevention and safety control for highway facilities during critical natural hazards with the progress of this study.
Characteristics and Control Priority of Hazardous Air Pollutants in the Metropolitan Areas : A Case Study in Tainan, Taiwan
Authors: Tsai Jiun-Horng , Tsai Hsiao-Hsuan
Published: March 2020

This research investigated the hazardous air pollutants (HAPs), also known as air toxics, emission profiles and the potential health risks in Tainan City in Taiwan. Emission profiles of HAPs were derived by source test data and speciation data bank. Emissions from stationary source, mobile source, and area source were estimated in this study. Airborne concentration of target HAPs had been simulated by Models-3/CMAQ simulation and followed by cancer risk assessments for control priority assessment.

Five species of air toxics were selected as target component in this study, which included benzene, formaldehyde, acetaldehyde, acrolein, and 1,3-butadiene, by weighting the emissions and toxicity factors. Emission estimation indicated that these target air toxics were released by stationary sources with 34.5, 35.0, 5.0, 72.3, 94.5 %, respectively. Emissions of these 5 air toxics from mobile sources were 62.8, 45.4, 94.7. 27.5, 3.5 %, respectively. Area sources contributed less fraction in the city. The simulated annual average concentrations of target air toxics indicated the hot zone of various HAPs present in different location in the city. The airborne concentration of benzene and acetaldehyde in hot zone were mainly caused by mobile source emissions. Concentrations of formaldehyde in hot zone was caused by various sources. Airborne concentrations of acrolein and 1,3-butadiene in hot zone were mainly caused by area sources. The potential health risk assessment imposed by these target air toxics were evaluated by simulated exposure concentrations and with inhalation unit risk factor (cancer risk) and reference concentration level (non-cancer risk), respectively. The results showed 1,3-butadiene would pose the highest carcinogenic potential in the city which were mainly released by area sources. Acrolein had the highest non-carcinogenic potential. The cancer burden, by considering population density and exposure concentration, was higher in downtown area. Formaldehyde was the critical HAP which would impose the highest impacts on people caused by dense emission from mobile sources.
How does silica affect Fe(II)-catalysed transformation of ferrihydrite and lepidocrocite?
Authors: Schulz Katrin , ThomasArrigo Laurel Kathleen , Rothwell Katherine Ann , Kretzschmar Ruben
Published: March 2020

Ferric iron (Fe(III)) minerals, such as ferrihydrite and lepidocrocite, can be reduced to ferrous iron (Fe(II)) through microbial reductive dissolution under reducing soil conditions, to form dissolved Fe(II) or mixed Fe(II)-Fe(III) mineral phases. The dissolved Fe(II) catalyses iron mineral transformation to more crystalline iron phases. Silica (Si), in the form of silicic acid, is an ubiquitous component of natural soil solutions and is known to hinder the iron mineral transformation process. However, the mechanisms and the mineral phases that are formed during ferrihydrite and lepidocrocite transformation in the presence of Si remain unclear. We reacted ferrihydrite, Si-ferrihydrite co-precipitates, lepidocrocite and Si-adsorbed lepidocrocite with 0.3 mM and 3 mM isotopically labelled 57Fe(II) for four weeks. At six time points, we sampled the solid and the aqueous phase, to follow iron mineral transformation by X-ray diffraction and dissolved Fe(II) dynamics. In addition, we tracked the iron atom exchange between the aqueous and the solid phase by measuring the 57/56Fe isotope ratio in filtrates and dissolved solid phases. Our data demonstrates the hindering effect of Si on Fe(II) catalysed ferrihydrite and lepidocrocite transformation. The presence of Si decreased the initial Fe(II) adsorption and strongly slowed down the iron atom exchange, especially in the lepidocrocite treatment. Collectively, the results of this study demonstrate, how Si can impact iron mineral transformation in soils with different Fe(II) release potentials under reducing conditions.
Use of WWI photos for quantitative reconstructions of glaciers along the Italian-Austrian front
Authors: Carturan Luca , Bondesan Aldino , Carton Alberto , Cazorzi Federico , Cucchiaro Sara , De Marco Jessica , Piermattei Livia
Published: March 2020

The knowledge of past fluctuations of glaciers is the key for understanding their dynamics and their climate-related evolution. Glacier mass balance and length changes are the two metrics normally used for reconstructing past fluctuations series of glaciers. However, length change measurements series are often discontinuous and require validation, whereas mass balance measurements are available for only a few glaciers worldwide and only for the latest decades.

In the context of glacier reconstructions, other sources of information such as historical-archival, glacio-archaeological and geomorphological data are of critical importance, because they enable the completion and validation of direct measurement series and their extension into the past, providing spatial and temporal constraints.

A unique source of unexploited historical information dating back to the First World War (WWI, 1915-1918) exists for many glaciers in the Eastern Italian Alps. This information mainly consists of old photos, which however are spread over a multitude of sources, often difficult to access, and in many cases not yet digitized.

We propose a workflow that enables extracting quantitative information from terrestrial photographs taken during the WWI period, aimed at the reconstruction of glacier area, volume and firn lines by means of the monoplotting technique. This method relies on the availability of high-resolution digital elevation models, which became recently available over wide areas thanks to LiDAR and aerial photogrammetry. This work presents the methods applied, and the results obtained, on several case studies in the Adamello-Presanella, Ortles-Cevedale, Dolomites, and Julian Alps.    
Success of the co-production and delivery of local and scientific weather forecasts information with and for smallholder farmers in Ghana
Authors: Gbangou Talardia , Sarku Rebecca , Vanslobbe Erik , Ludwig Fulco , Kranjac-Berisavljevic Gordana , Paparrizos Spyridon , Dewulf Art
Published: March 2020

Many West African farmers struggle to cope with changing weather and climatic conditions that keep them from making optimal decisions and meeting food and income security. The development of more accessible and credible weather and climate services (WCIS) can help local farmers improve their adaptive capacity. Such adequate WCIS often requires a joined collaboration between farmers and scientists to co-create an integrated local and scientific forecasting knowledge. We examine (i) the design requirements (i.e. Both technical and non-technical tools) and (ii) evaluate the outcomes of a successful implementation of the co-production and delivery of WCIS in Ada East district, Ghana. We implemented a user-driven design approach in a citizen science experiment involving prototype design and testing, training workshops, and interviews with farmers, agricultural and meteorological extension agents from 2018 to 2019. Farmers were handed with digital tools (i.e. Smart phones with web and mobile applications) and rain gauges as research instruments to collect and receive weather forecast data, and interact with scientists.

               Our results show that farmers’ engagement increased over time and is associated with the trainings and the improvement of the design features of the applications used. The evaluation shows an increase in the usability of tools, the reach or networking with other farmers, and the understanding of uncertainty (probabilistic) aspect of the forecasts over time. Local farmers evaluated both the local and scientific forecasts as accurate enough and useful for their daily farming decisions. We concluded that using modern technology in a co-production process, with targeted training, can improve the access and use of weather forecasts information.
Between Land and Sea: An analysis of the landscape changes in the Chekka region (Lebanon) based on airborne LiDAR data and historical aerial images from 1962
Authors: Rom Jakob , Haas Florian , Stark Manuel , Poschenrieder Andreas , Kopetzky Karin , Genz Hermann
Published: March 2020

The project “Between Land and Sea” was initiated by OREA (Institute for Oriental and European Archaeology) and is an interdisciplinary approach to combine the geology, geomorphology, and paleo-environment of the Chekka region (Lebanon) to investigate the ancient history and its archaeological remains. In the course of the project, the first ever scientific LiDAR (Light Detection and Ranging) data acquisition in Lebanon was conducted in autumn 2018 and a high-resolution DEM (Digital Elevation Model) was calculated. However, this model represents the recent topographical situation, which has changed drastically not only in the archaeologically relevant period up to 5000 years before today but also during the last decades.

To be able to qualitatively and quantitatively record geomorphological processes in the study area and thus understand long-term natural and anthropogenic landscape changes, the recent elevation model is compared with a historical model. The historical elevation model was derived on the base of aerial images of a French overflight from 1962. With the help of SfM (Structure from Motion/Agisoft Metashape) in combination with referencing methods (e.g. ICP), this historical model can be adapted to the LiDAR model. Quantitative analyses of selected areas provide information about surface changes over the last 56 years. But these results give also ideas about landscape evolution over longer time periods. Besides the natural changes, the historical model also reveals major anthropogenic changes since 1962 and shows that possible archaeologically relevant sites have been lost as a result of extensive overprinting due to the construction of buildings, infrastructure, industrial mining or agricultural use.

Our promising results show, that the implementation of historical terrain models based on aerial photographs can lead to a better understanding of the natural landscape development as well as anthropogenic induced changes and thus can also provide important additional information for archeological surveys.
Growth and wood anatomical adjustments of Fraxinus excelsior to the infestation of the invasive fungus Hymenoscyphus fraxineus
Authors: Klesse Stefan , von Arx Georg , Gossner Martin , Hug Christian , Rigling Andreas , Queloz Valentin
Published: March 2020

Since the 1990s the invasive fungus Hymenoscyphus fraxineus has led to severe crown dieback and high mortality rates in Fraxinus excelsior in Europe. In addition to a strong genetic control of tolerance to the fungus, previous studies have found high landscape variability in the severity of dieback symptoms. However, apart from heat and humidity-related climate conditions favoring fungal development the mechanistic understanding of why smaller or slower growing trees are more susceptible to dieback remains less well understood.

Here, we analyzed three stands in Switzerland with a unique setting of eight years of intra-annual diameter growth and annual crown health assessments, together with ring-width and quantitative wood anatomical measurements preceding the monitoring, to investigate if wood anatomical adjustments can help better explaining the size-related dieback phenomenon.

We found that slower growing trees or trees with smaller crowns already before the arrival of the fungus were more susceptible to dieback and mortality. We show that defoliation directly reduces growth as well as maximum earlywood vessel size, and that the positive relationship between vessel size and growth rate causes a positive feedback amplifying crown dieback. Because leaf necrosis happens during late summer when ring formation has already finished, photosynthesis is heavily reduced during a time when non-structural carbohydrates (NSCs, sugars and starch) are stored. Thus, we hypothesize that a lack of NSCs (mainly sugars) leads to lower turgor pressure and smaller earlywood vessels in the next year impeding efficient water transport and photosynthesis, and is responsible why smaller and slower growing trees show stronger symptoms of dieback and higher mortality rates.
Connections between climate sensitivity and the extratropical circulation
Authors: Davis Luke , Thompson David , Birner Thomas
Published: March 2020

The dry dynamical core represents one of the simplest possible numerical models for studying the response of the extratropical circulation to climate change. In the model, the circulation is forced by relaxing temperature to a notional “equilibrium” using linear damping. The linear damping coefficient plays an essential role in governing the structure of the circulation. But despite decades of research with the dry dynamical core, the role of the damping coefficient in governing the circulation has received relatively little scrutiny.

In this work, we systematically vary the damping coefficient in a dry dynamical core in order to understand how the amplitude of the damping influences extratropical dynamics. Critically, we prove that the local climate feedback parameter is proportional to the damping coefficient – that is, the damping timescale is a measure of climate sensitivity for the dry atmosphere. The key finding is that the steady-state extratropical circulation responds to changes in this climate sensitivity.

Longer damping timescales (i.e. higher climate sensitivities) lead to a less dynamically active extratropical circulation, stronger and more persistent annular modes, and equatorward shifts in the jet. When perturbed with climate change-like forcings, changing the damping timescale can also change the dynamical response to the forcing. We argue that understanding the response of the circulation to climate change is critically dependent on understanding its climate sensitivity, and consider how climate sensitivity might be inferred from its effect on the circulation in the dry model and more complex general circulation models.