bluuebunny/crossref_metadata_2025 huggingface dataset:
On forest monitoring and reporting in developing countries: lessons learnt and way forward
Authors: Jonckheere Inge , Mertens Esther
Published: March 2020

Under the COP Paris Agreement, countries need to prepare their GHG inventories with emissions by source and removals by sinks. In order to meet the UNFCCC quality standards, those inventories should be transparent, accurate, comparable, consistent and complete. For the LULUCF sector, emissions are a result from a change in one of the five IPCC carbon pools (e.g. aboveground biomass, etc.). The change in the carbon stock is not easily directly measured, but usually estimated using proxies of land area and area change and the average carbon stocks in the area. Countries encounter several challenges when collecting forestry and land use data information on land related to the inherent complexity of the measurement and monitoring of LULUCF sector and limited by their institutional arrangements. The REDD+ program of the United Nations has a long history of supporting developing countries on setting up the forest (and land use) monitoring system which has supported several countries to produce regular data and make it publicly available, even using web-geoportals. In this paper, we list the challenges of forestry and land data collection and demonstrate the potential leading role of REDD+ countries in the context of reporting regular GHG estimates for the LULUCF sector and the preparation of GHG baselines for the NDC progress reporting under the Paris Agreement, also in light with the recent developments in the COP25.

Key terms: Institutional arrangements, institutional memory, data management systems, legal instruments, sustainability, national forest monitoring system, LULUCF reporting, regular monitoring of land use data, preparation of land use change data. Data portals for increased transparency and stakeholder involvement. Targeted finance for data measurements at different agencies involved in the GHG inventory
Land-use change and climate change mitigation potential of agricultural soils in Finland
Authors: Tupek Boris , Lehtonen Aleksi , Mäkipää Raisa , Peltonen-Sainio Pirjo , Huuskonen Saija , Palosuo Taru , Heikkinen Jakko , Regina Kristiina
Published: March 2020

We aimed to estimate a nation-wide potential to improve the carbon balance of the land use sector by removing part of the current croplands on mineral soil from food and feed production to extensive grasslands or afforestation in Finland.  We combined the existing data on forest and agricultural production, and climate with predictive capacity of YASSO07 soil carbon model to estimate changes of soil carbon stock (SOC) in Finland over the past land use change (LUC) from forest to agriculture in comparison with alternative LUC or continuous agriculture in future.

The model analysis revealed that SOC loss after deforestation during the cultivation period originated mainly from the absence of woody litter input. The non-woody litter input of the forest was comparable to that of the agricultural residues thus the SOC originating from non-woody litter has not changed much during cultivation. The model estimated approximately a 30 year delay in positive soil carbon balance after the afforestation. Longer for Norway spruce than for the Pubescent birch. The comparison of two dominant tree species used for afforestation highlighted a difference in soil versus biomass carbon sequestration. The total forest biomass production and total carbon stock was larger for spruce stands than for birch stands. However, due to larger foliar and fineroot litter input birch stands sequestered more carbon into the soil than spruce stands. The analysis further revealed that extensification of cropland to grassland would not meet 4 per mill soil carbon sequestration criterion needed for achieving Paris climate CO2 reduction target and due to the spatial limitation of afforestation other management measures need to be considered e.g. adding biochar to soils for successful and more permanent CO2 offsetting.
Projection of future direct and indirect impacts of urban expansion on carbon storage: A case study in Hubei, China
Authors: Tang Lanping , Ke Xinli
Published: March 2020

Urban expansion encroaches on natural habitat, which seriously affects carbon storage which plays an important role in global climate change. The projection of future effects of urban expansion on carbon storage have been the subject of attention, previous studies explored its direct impacts but ignored indirect effects: cropland loss caused by urban expansion needs to compensation from natural habitat for food security, which also affects carbon storage. China, as a populated country, is at an important stage of cropland conservation policies reform, rapid urbanization, and constructing of eco-civilization. In this case, it’s vital to figure out the change of carbon storage due to the direct and indirect impacts of urban expansion in the future. Taking Hubei as the study area, the aim of this study is to project both direct impacts (DI) and indirect impacts (II) of urban expansion on carbon storage during 2010–2030. Three scenarios are developed by integrating the current situation and policies: the scenarios where urban continues to expand and the cropland conservation policies are implemented with the priority to cropland in quantity (S1), with the priority to cropland in quantity and quality (S2), with the priority to cropland in quantity and quality, and ecological protection is also concerned (S3). Results show that, the total loss of carbon storage caused by urban expansion will be 1.83Tg•C (DI: 0.95Tg•C; II:0.88Tg•C) under the S1 scenario, will be 2.15Tg•C (DI: 1.46Tg•C; II:0.69Tg•C) under the S2 scenario, and will be 1.49Tg•C (DI: 0.94Tg•C; II: 0.55Tg•C) under the S3 scenario. This indicates that ignoring the indirect impacts of urban expansion on carbon storage will lead to the underestimation of real impacts of urban expansion with 48%, 32%, and 63%, respectively. This study highlights the importance of taking the carbon storage loss caused by the indirect impacts of urban expansion into consideration.
Integrated analysis of multi-scale electrical signatures for characterizing soil water dynamics in century-old biochar enriched agroecosystems
Authors: Placencia-Gomez Edmundo , Burgeon Victor , Heidarian-Dehkordi Ramin , Meersmans Jeroen , Cimpoiasu Mihai , Fouché Julien , Nguyen Frederic , Cornelis Jean-Thomas , Garré Sarah
Published: March 2020

Electrical resistivity and induced polarization tomography and electromagnetic induction are widely used in hydrogeophysical applications. In this work we perform a multi-scale analysis of DC-resistivity, spectral induced polarization (SIP) and electromagnetic induction (EMI) measurements to evaluate soil water dynamics of a century-old biochar enriched agroecosystem. Our study aims at comparing the spatio-temporal variations of the electrical signature (resistivity or conductivity) between the natural (reference) soil and soil enriched with biochar visible as black patches ( 0.30 m thick x 20 m of diameter) in the study area and relate this signature to a soil moisture status. In this first overall and qualitative approach we combine 1) field large-scale time-lapse electrical resistivity tomography (ERT) transects (12.6 m) and EMI conductivity maps covering the whole study area (13 ha), 2) intermediate-scale ERT/SIP profiles from on-site pits (2 m L x 1 m W x 1 m D), and 3) laboratory columns-scale (0.10 m L x 0.044 m ID) SIP signatures of undisturbed soil samples.

Large-scale results show a heterogeneous-resistive soil top horizon in both soil types, but with similar hydrodynamic behaviour following precipitation events. The column scale SIP signatures reveal that texture and pore structure are the main driver of soil moisture dynamics with insignificant role of the biochar content. Large and intermediate scale monitoring campaigns during the entire growing season of two different crops are planned for the current and next year. The ultimate objective is to quantify the effect of century-old biochar on soil water dynamics and root water uptake.
Paleogeothermal Gradients across an Inverted Hyperextended Rift System (Mauléon Fossil Rift,Western Pyrenees)
Authors: Saspiturry Nicolas , Lahfid Abdeltif , Baudin Thierry , Guillou-Frottier Laurent , Razin Philippe , Issautier Benoit , Le Bayon Benjamin , Serrano Olivier , Lagabrielle Yves , Corre Benjamin
Published: March 2020

Examples of fossil and present-day passive margins resulting from mantle exhumation at the ocean–continent transition appear to have developed under conditions of high mantle heat flow. The pattern of geothermal gradients along these hyperextended margins at the time of rifting is of interest for exploration of geothermal and petroleum resources, but is difficult to access. The fossil rift in the North Pyrenean Zone, which underwent high temperature–low pressure metamorphism and alkaline magmatism during Early Cretaceous hyperextension, was studied to explore the geothermal regime at the time of rifting. Data from a set of 155 samples from densely spaced outcrops and boreholes, analyzed using Raman spectroscopy of carbonaceous material, shed light on the distribution of geothermal gradients across the inverted hyperextended Mauléon rift basin during Albian and Cenomanian time, its period of active extension. The estimated paleogeothermal gradient is strongly related to the structural position along the Albian-Cenomanian rift, increasing along a proximal-distal margin transect from ~34°C/km in the European proximal margin to ~37–47°C/km in the two necking zones and 57–60°C/km in the hyperextended domain. This pattern of the paleogeothermal gradient induced a complex competition between brittle and ductile deformation during crustal extension. A numerical modeling approach reproducing the thermal evolution of the North Pyrenees since 120 Ma suggests that mantle heat flow values may have peaked up to 100 mW.m-2 during the rifting event. We demonstrate that the style of reactivation during subsequent convergence influences the thermal structure of the inverted rift system.
Relationships between corridor morphological variables and avalanche deposits volumes
Authors: Kern Hippolyte , Jomelli Vincent , Eckert Nicolas , Grancher Delphine
Published: March 2020

Avalanche deposits cause various types of damage to properties and infrastructures every winter, resulting in significant direct and indirect economic losses. However, the factors controlling the deposit volumes are still largely unknown. The main objective of this study is to analyze the geometric characteristics of avalanche deposits in order to understand their relationships with the avalanche corridors’ morphology in the French Alps. Our study focuses on the analysis of 1491 avalanche deposits spread out over 79 corridor in the upper part of the Haute-Maurienne valley, Savoie department, during the period 2003-2017. This work uses data from the Permanent Avalanche Survey (EPA) database, an inventory of avalanche events occurring at well-known, delineated and mapped corridors in France. A statistical method is used to study the relationships between corridor morphological variables and their associated deposit volumes. Our study area exhibits an mean deposit volume of 17 500m3 (q5% = 4 500 m3 and q95%= 84 000 m3).

 Results show that the relationships between corridor morphology and deposit volumes are only significant (⍴ > 0,3 and P < 0,001) for avalanches that occur in winter (November-February). The frequency of snow avalanches also influences the size of the deposits, with the largest deposits observed in corridors that show high annual avalanche frequency. However, avalanche deposit volumes occurring in corridors with a low annual frequency correlate more strongly with the corridor morphology. On the other hand, snow avalanche volumes deposited in spring (March-May) seem to be mostly driven by meteorological variables with almost no correlation with the corridor’s morphology. In more details, deposit volumes are primarily determined by the corridor maximum or mean altitude, which reflects the potential amount of snow that can be mobilized. Corridor slope also exhibit a significant relationship with deposit volumes, which is partially indirect through the effect of the slope on corridors mean annual avalanche frequency. Eventually, surprisingly enough, morphological variables that may intuitively appear as important for deposit volumes such as surface area or orientation are uncorrelated or only poorly correlated with avalanche deposit volumes.
High resolution imaging of fault reactivation in long-lived extensional setting: a case study from the Exmouth Plateau (NW Australia)
Authors: D'Intino Nico
Published: March 2020

Extension in rift zones and passive margins often occur by multiphase normal faulting which usually accommodates several episodes of lithosphere stretching by brittle deformation. In these settings, pre-existing normal faults may reactivate but also new-formed structures may nucleate, with multiple orientations and deformational styles. The various modes of fault growth and nucleation are strongly influenced by several parameters (including orientation and geometry of pre-existing discontinuities, stress orientation and magnitude, strain rates, confining pressure, etc..) with the lithostratigraphy controlling the brittle or ductile litho-mechanic behavior of each unit.

In this work, we interpreted and analyzed an industrial 3D seismic volume acquired in the Exmouth Plateau, (Northern Carnarvon Basin – offshore NW Australia), where pre-existing Mesozoic normal faults were reactivated during the Cenozoic and controlled the nucleation and growth of the new-formed overlying fault segments. The peculiarity of this system is that the two sets of faults are separated by a ductile interval of shales. The latter acted as decollement level and promoted the formation of prominent faulted anticlines in the overlying brittle sequence; these forced folds are poorly documented in other extensional settings while are common where salt layers are present. In this study, the high-resolution techniques adopted for seismic data interpretation aimed to understand the geometries of faults and their interactions in fine detail. The results of fault analysis suggest that the use of high-quality 3D seismic volumes is very useful to unravel the complex and subtle spatial variability and also the displacement pattern of faults with a limited amount of fault-throw.
The characteristics and drivers of climatological precipitation over the Serengeti-Mara region
Authors: Mahony Josephine , Dyer Ellen , Washington Richard
Published: March 2020

The Serengeti National Park is famous for the biological phenomenon of the annual wildebeest migration. This migration is reliant on unique local precipitation conditions: a rainfall gradient stretching across the park, the strength and inclination of which alters from month to month. Given the ecological significance and the complexity of the regional precipitation, a detailed study of the region’s climatology is essential for understanding why these precipitation patterns exist, and whether they are likely to change.

Using multiple observational datasets, we studied the spatial distribution of annual and monthly climatological precipitation. We carried out harmonic analysis and cluster analysis to identify areas with similar annual cycles. We then examined regional wind, moisture and precipitation patterns on seasonal, monthly and diurnal timescales.

We found that the large-scale wind circulation patterns dictate the basic structure of the annual cycle over the region. However the shape of the annual cycle was distinctly different in 5 parts of the region, with varying peak rainfall months and dry season rainfall totals. Analysis of the diurnal wind patterns showed that the regional seasonality is strongly augmented by the lake and land breeze from Lake Victoria, and the interactions between this local source of moisture and the complex topography of the East African rift. This leads to a low-level convergence zone between the prevailing large-scale easterlies, and westerlies from Lake Victoria over the Serengeti in the afternoon. This in turn results in the rainfall gradient across the region, the orientation of which changes depending on the mid-tropospheric wind direction.
Upscaled modelling of natural fracturing and leakage due to high overpressures
Authors: Lothe Ane Elisabet , Grøver Arnt , Roli Ole-Andre
Published: March 2020

In sedimentary basins highly overpressured formations and zones are observed worldwide. The high overpressures have been generated over millions of years due to sedimentation amount and rate, compaction, lateral fluid flow, diagenesis and other processes. The lateral fluid flow is often controlled by the fault pattern and sealing properties of the faults in the area, thus defining what is often termed pressure compartments. When high overpressures builds-up over time in such compartment, eventually natural hydraulic faulting and fracturing will start to develop to cease and relief the overpressure.

In this work we have aimed to simulate fracture generation, how they in an upscaled approach evolve and progress upwards, and how this will influence the water fluid flow and the pore pressure distribution. We use an in-house software (PressureAhead) to simulate three-dimensional water fluid pressure generation and dissipation over millions of years. Interpreted seismic horizons for the whole stratigraphy are back-stripped (decompaction) in order to provide the basin burial history as input to the forward simulator. Uplift and erosion events are included. For each timestep, the effect of pressure generation and dissipation is calculated. For the fault and failure development, the combined Griffith-Coulomb failure criteria are implemented to calculate when failure occurs, secondly, when the fracture has been formed and the cohesion is lost, the frictional sliding criteria is used. The fractures are in this approach working as a pressure valve, that will stay open as long as the pressure support is large enough. Compared to previous approach, the failure criteria is now evaluated for the whole stratigraphic column in 3D Using this approach, the effect of natural fracturing taking place in different parts of the basin at different geological events can be modelled.

The new simulation approach will be presented for a dataset from the deeper part of the Viking Graben, North Sea offshore Norway. The study area covers an NNE-SSW trending graben defined by large faults. Seventeen seismic horizons (resolution 50x50 m) from Middle Jurassic to seafloor have been used to set up the model. The modelling is carried out over the 150 My, with time steps of 250 000 years. Examples of varying key input parameters will be shown. Strength and weakness with such an upscaled modelling framework will be discussed.
Energetic Particles in the Inner Heliosphere: Solar Orbiter
Authors: Wimmer-Schweingruber Robert F. , Rodriguez-Pacheco Javier , Böttcher Stephan , Cernuda Ignacio , Dresing Nina , Dröge Wolfgang , Eldrum Sandra , Espinose Lara Francisco , Gomez-Herrero Raul , Heber Bernd , Ho George , Klassen Andreas , Kollhoff Alexander , Kulkarni Shrinivasrao , Mann Gottfried , Martin César , Mason Glenn , Pacheco Daniel , Prieto Manuel , Sanchez Sebastian ,   Robert F. Wimmer-Schweingruber
Published: March 2020

To be measured as energetic particles in the heliosphere ions and electrons must undergo three processes: injection, acceleration, and transport. Suprathermal seed particles have speeds well above the fast magnetosonic speed in the solar wind frame of reference and can vary from location to location and within the solar activity cycle. Acceleration sites include reconnecting current sheets in solar flares or magnetospheric boundaries, shocks in the solar corona, heliosphere and a planetary obstacles, as well as planetary magnetospheres. Once accelerated, particles are transported from the acceleration site into and throughout the heliosphere. Thus, by investigating properties of energetic particles such as their composition, energy spectra, pitch-angle distribution, etc. one can attempt to distinguish their origin or injection and acceleration site. This in turn allows us to better understand transport effects whose underlying microphysics is also a key ingredient in the acceleration of particles.

In this presentation we will present some clear examples which link energetic particles from their observing site to their source locations. These include Jupiter electrons, singly-charged He ions from CIRs, and 3He from solar flares. We will compare these examples with the measurement capabilities of the Energetic Particle Detector (EPD) on Solar Orbiter and consider implications for the key science goal of Solar Orbiter and Solar Proble Plus – How the Sun creates and controls the heliosphere.
Engaging the Community in the Development of Physics for NWP Models
Authors: Bernardet Ligia , Firl Grant , Heinzeller Dom , Carson Laurie , Sun Xia , Pan Linlin , Zhang Man
Published: March 2020

Contributions from the community (national laboratories, universities, and private companies) have the potential to improve operational numerical models and translate to better forecasts. However, researchers often have difficulty learning about the most pressing forecast biases that need to be addressed, running operational models, and funneling their developments onto the research-to-operations process. Common impediments are lack of access to current and portable model code, insufficient documentation and support, difficulty in finding information about forecast shortcomings and systematic errors, and unclear processes to contribute code back to operational centers. 

The U.S. Developmental Testbed Center (DTC) has the mission of connecting the research and operational Numerical Weather Prediction (NWP) communities. Specifically in the field of model physics, the DTC works on several fronts to foster the engagement of community developers with the Unified Forecast System (UFS) employed by the U.S. National Oceanic and Atmospheric Administration (NOAA).  As a foundational step, the UFS’ operational and developmental physical parameterizations and suites are now publicly distributed through the Common Community Physics Package (CCPP), a library of physics schemes and associated framework that enables their use with various models. The CCPP can be used for physics experimentation and development in a hierarchical fashion, with hosts ranging in complexity from a single-column model driven by experimental case studies to fully coupled Earth system models. This hierarchical capability facilitates the isolation of non-linear processes prior to their integration in complex systems. 

The first public release of a NOAA Unified Forecast System (UFS) application is expected for February 2020, with a focus on the Medium-Range Weather Application. This global configuration uses the CCPP and will be documented and supported to the community. To accompany future public releases, the DTC is creating a catalog of case studies to exemplify the most prominent model biases identified by the US National Weather Service. The case studies will be made available to the community, who will be able to rerun the cases, to test their innovations and document model improvements. 

In this poster we will summarize how we are using the UFS public release, the single-column model, the CCPP, and the incipient catalog of code studies to create stronger connections among the groups that diagnose, develop, and produce predictions using physics suites.
Investigating the GDP-CO2 relationship using a neural network approach
Authors: Jensen Sebastian , Hillebrand Eric , Bennedsen Mikkel
Published: March 2020

Exploiting a national-level panel of per capita CO2 emissions and GDP data, we investigate the GDP-CO2 relationship, using a data-driven approach. We conduct an in-sample analysis in which we investigate the shape of the GDP-CO2 relationship. Utilizing the shape of the GDP-CO2 relationship learned, we project CO2 emissions through 2100, using the same set of GDP and population growth scenarios as used by the Intergovernmental Panel of Climate Change (IPCC) for their sixth assessment report due for release in 2021-22. Our analysis is carried out at two levels: at a global, and at the level of ﬁve large regions of the world. We consider a semiparametric model speciﬁcation which places no restrictions on the functional relationship between GDP and CO2, but which allows for country and time speciﬁc ﬁxed eﬀects. The nonparametric component of our model is speciﬁed as a feedforward neural network, ensuring universal approximation capabilities, theoretically. In a simulation study, we show that our model is able to capture various complex relationships in ﬁnite samples of realistic sizes.
Pulsating localised fluid expulsions
Authors: Räss Ludovic , Simon Nina S.C. , Podladchikov Yury Y.
Published: March 2020

A wide variety of fluid-rich natural systems exhibit a distinct pulsating signature on geophysical measurements. Identifying the processes leading to these observed pulses are key to further understand important multi-scale and multi-physics valve-like dynamics in natural environments such as gas flow in volcanic systems, magma transport in the crust, tremors and slip or subsurface flow migration. These natural two-phase systems share common features as they can be described as viscously deforming saturated porous media. They exhibit a time-dependant deformation of their porous matrix, buoyant pore-fluid, an effective pressure dependant bulk viscosity and a nonlinear porosity-permeability relation.

We here investigate the role of coupled hydro-mechanical processes to trigger pulsating localised fluid expulsions. We show that the pulsating regime may be a natural outcome of the interactions between a viscously deforming porous matrix and a nonlinear pore-fluid flow. We rely on high-resolution direct numerical two-phase flow calculations in three dimensions to explore what parameters control the main characteristics of the pulsating signal. We are particularly interested in how amplitudes, wave lengths and frequencies of the signal relate to the input model parameters.

We show that repeated fluid pulses are a natural outcome of the coupled Stokes and Darcy equations within the nonlinear viscous two-phase flow regime. We discuss the relevance of our findings in light of the valve-like behaviour in a variety of natural fluid-rich environments. We propose to use the characteristic of the pulsating signal to gain further insight in the dynamics of complex natural systems.
The Future of Earth and Planetary Observations from Space
Authors: Aschbacher Josef
Published: March 2020

Earth Observation is currently undergoing a major transformation driven by elements like data analytics, Artificial Intelligence/Machine Learning, and Big Data. Moreover, there are new actors – often from outside the traditional space sector –, new technical mission concepts and new ways of financing space projects. The presentation will give an overview of ESA’s Earth Observation programme with its major ‘pillars’, and its evolution in regard to the trends above. The presentation will also highlight the impacts of ESA’s Ministerial Conference in December 2019 that yielded excellent results for ESA in general and for Earth observation in particular. A special focus will be put on opportunities and perspectives of international cooperation.

 
Ensemble Water Level Prediction System: Improving the Representation of Model Uncertainty
Authors: Bernier Natacha , Huziy Oleksandr , Thompson Keith , Wang Pengcheng , Pouliot Benoit , Pell Syd
Published: March 2020

Concern over increased flooding and the need for earlier and more reliable risk forecasts motivate the continued development of operational forecasts of coastal water level. We report here on results from a year long ensemble of total water level forecasts calculated using a dynamical ocean model forced with ensemble atmospheric forcing and tidal boundary conditions. We focus on the east coast of Canada. The domain includes the Gulf of St. Lawrence, the Labrador Shelf, the Scotian Shelf, and the Gulf of Maine. The water level ensemble is made of a control and 20 perturbed members. Individual forecasts are produced twice daily for 16 days.

 

The novelty of the present study is in the exploration of perturbations of the ocean contributions. In addition to examining how uncertainty in atmospheric forcing maps into flood risk, we also explore the feasibility, and impact, of perturbing the ocean tides. We use a recent case study to demonstrate our findings.

 
Using GIS and Remote Sensing Techniques for Delineation of Groundwater Potential Zones - A Case Study of the Titel Municipality, Serbia
Authors: Radulović Mirjana , Đorđević Tijana , Grujić Nastasija , Pejak Branislav , Brdar Sanja , Savić Stevan , Pavić Dragoslav
Published: March 2020

Dramatic population growth and climate change lead to an increasing demand for groundwater resources. According to The 2018 edition of the United Nations World Water Development Report, nearly 6 billion people will face severe water scarcity by 2050. Groundwater represents the world’s largest available freshwater resource and it is essential for domestic purpose, industrial, and agricultural uses. Therefore, it is very important to identify the potential locations for new groundwater zones development. Here, we utilized geographic information system (GIS) and remote sensing (RS) techniques for the delineation of groundwater potential zones in the Titel Municipality, located in the Autonomous Province of Vojvodina. The groundwater in the study area is affected by elevation difference, agricultural production, and its geographical position. Titel Municipality has a very good agriculture potential that can be only fully exploited by improving groundwater management. Considering that, for the delineation of groundwater potential zones we prepared 6 thematic layers such as geology, geomorphology, land use/land cover, soil, drainage density, and slope. According to their relevant importance in groundwater occurrence, all layers and their features were assigned weights using the Saaty’s scale. Weights of layers were normalized using analytical hierarchical process techniques (AHP). Finally, layers were integrated and overlaid using QGIS software for generating the Groundwater Potential Zone (GWPZ) map of the study area. As a result, the groundwater potential zones in the Titel Municipality were characterized and classified into five classes as very good (7.13%), good (35.44%), moderate (21.27%), poor (31.41%) and very poor (3.11%). With these techniques, we showed that very good and good groundwater zones are predominantly located in the alluvial plain and the lower river terrace, while poor zones mostly evident on the landform of the loess plateau and artificial surface. The GWPZ map will serve as a useful guide for sustainable management and utilization of the region as well as to improve the irrigation facility and develop the agriculture productivity of the area.
Activation of soil enzymes by addition of artificial root exudate combinations
Authors: Hagmann Diane , Krumins Jennifer , Vaidya Bhagyashree , Goodey Nina
Published: March 2020

In vegetated soils,plants naturally release root exudates, consisting of sugars, organic acids, and amino acids, into the soil increasing soil enzymatic activity.  Liberty State Park, located in Jersey City, New Jersey, is an industrial brownfield contaminated with heavy metals and organic pollutants.  Some sites have soils that function poorly, as indicated by low soil enzymatic activity, and do not support plant growth.  This study will determine whether different combinations of artificial root exudates increase soil enzymatic activity in these contaminated and low functioning soils. Different combinations of sugars, organic acids, and amino acids and will be added to barren, poorly functioning soil.  Three soil enzymatic activities will be examined at several time points over 120 days to assess the impacts of different combinations of root exudates on soil function. Further, soil microbial community composition will be determined to examine whether different artificial exudate solutions result in changes in soil microbial community.  Preliminary results suggest that the combination of sugars, organic acids, and amino acids greatly increased phosphatase, cellobiohydrolase, and L-leucine amino peptidase activity over time in poorly-functioning, barren soil from Liberty State Park. The other combinations (sugars and organic acids, sugars and amino acids, organic acids and amino acids) also increase the three enzyme activities more than the individual groups. Dormant microbes in barren soil can possibly be revived with the addition of artificial root exudates to mimic the presence of plants in revitalizing the microbial communities and improving soil function. 
Winter Arctic sea ice bottom evolution detected by thermistor string-based ice mass balance buoys (SIMBA)
Authors: Cheng Bin , Vihma Timo , Liao Zeling , Lei Ruibo , Hoppmann Mario , Qiu Yubao , Pirazzini Roberta , Sandven Stein
Published: March 2020

A thermistor-string-based Snow and Ice Mass Balance Array (SIMBA) has been developed in recent years and used for monitoring snow and ice mass balance in the Arctic Ocean. SIMBA measures vertical environment temperature (ET) profiles through the air-snow-sea ice-ocean column using a thermistor string (5 m long, sensor spacing 2cm). Each thermistor sensor equipped with a small identical heating element. A small voltage was applied to the heating element so that the heat energy liberated in the vicinity of each sensor is the same. The heating time intervals lasted 60 s and 120 s, respectively. The heating temperatures (HT) after these two intervals were recorded. The ET was measured 4 times a day and once per day for the HT.

A total 15 SIMBA buoys have been deployed in the Arctic Ocean during the Chinese National Arctic Research Expedition (CHINARE) 2018 and the Nansen and Amundsen Basins Observational System (NABOS) 2018 field expeditions in late autumn. We applied a recently developed SIMBA algorithm to retrieve snow and ice thickness using SIMBA ET and HT temperature data. We focus particularly on sea ice bottom evolution during Arctic winter.

In mid-September 2018, 5 SIMBA buoys were deployed in the East Siberian Sea (NABOS2018) where snow was in practical zero cm and ice thickness ranged between 1.8 m – 2.6 m. By the end of May, those SIMBA buoys were drifted in the central Arctic where snow and ice thicknesses were around 0.05m - 0.2m and 2.6m – 3.2m, respectively. For those 10 SIMBA buoys deployed by the CHINARE2018 in the Chukchi Sea and Canadian Basin, the initial snow and ice thickness were ranged between 0.05m – 0.1cm and 1.5m – 2.5m, respectively.  By the end of May, those SIMBA buoys were drifted toward the north of Greenland where snow and ice thicknesses were around 0.2m - 0.3m and 2.0m – 3.5m, respectively. The ice bottom evolution derived by SIMBA algorithm agrees well with SIMBA HT identified ice-ocean interfaces. We also perform a preliminary investigation of sea ice bottom evolution measured by several SIMBA buoys deployed during the MOSAiC leg1 field campaign in winter 2019/2020.  
Hydrodynamic Stressing and the Response of Endangered Freshwater Pearl Mussels to Turbulent Flows
Authors: Curley Edward , Thomas Rhian , Adams Colin , Valyrakis Manousos , Stephen Alastair
Published: March 2020

Whilst there is encouragement to be taken from the fact that Scotland remains a stronghold for M. margaritifera populations, a trend of continued population decline persists. Our understanding of the hydraulic characteristics associated with successful M. margaritifera proliferation in the wild is poor. Additionally, evidence to suggest how M. margaritifera respond to variation in the associated parameters, is limited. The primary motif of this research project is to address the knowledge gap. Initial experimental analysis sought to establish a non-invasive method of quantifying acute mussel stress; using behavioural response indicators, coupled with measures of physiological condition. Results from this work have provided a foundation for investigating mussels as biosensors to remotely track alterations in chemical, hydraulic, and geomorphological parameters. Further research has investigated the response of live mussels to alterations in flow depth, with consideration of riverbed geomorphology, in both a laboratory flume and regulated river. Current experimental work in a laboratory flume is utilising remote sensor technology to understand the impact of flow velocity on mussel behaviour; examining how flow velocity may impact habitat selection, and how a mussel’s behaviour may in turn affect the surrounding hydrodynamics. The results emanating from this research will be novel and will ultimately provide urgently needed empirical data to drive future conservation strategies implemented by government (SNH, SEPA) and utilized by the hydroelectric industry (SSE).
A calibrated 3D thermal model of urban heat fluxes into the shallow subsurface
Authors: Kreitmair Monika , Bidarmaghz Asal , Terrington Ricky , Farr Gareth , Choudhary Ruchi
Published: March 2020

The growth of urban populations, combined with the limited availability of above-ground space, is resulting in the increased use of underground structures as living spaces, e.g. residential basements. Such subsurface structures constitute continuous sources and sinks of heat to and from the surrounding underground environment, particularly if maintained at comfortable temperatures. In heavily populated cities and city-centres, underground temperature increases due anthropogenic heat fluxes are well-established, known as the urban underground heat island effect. Due to limited availability of long-term underground temperature data, models looking at subsurface temperature changes caused by man-made structures are difficult to calibrate. However, accurately accounting for the underground thermal climate is essential in ensuring efficient heating and cooling of underground structures as well as correctly estimating the geothermal potential in areas affected by the heat fluxes. The work to be presented explores the impact of temperature-maintained subsurface structures on the thermal climate of the shallow subsurface by developing a 3D finite element model of the Cardiff (UK) city-centre, using COMSOL Multiphysics. The model takes into account conductive and convective heat transfer between the ground and basements as well as geological features and existing hydraulic head measurements. Calibration of the model is performed using time-series temperature data, collected over several years by monitoring boreholes distributed throughout the modelled domain, provided by the British Geological Survey. This constitutes an important step towards accurately characterising the effects of underground urban heat islands and better understanding the human impact on the below ground thermal climate.
Generation of a multi-decadal Earth Radiation Budget Thematic Climate Data Record : Balancing accuracy, precision, and availability to meet the needs of the community
Authors: Priestley Kory , Shankar Mohan , Thomas Susan
Published: March 2020

NASA’s Earth Radiation Budget Science Team, ERB-ST, (Previously known as the CERES Science Team) is a multi-disciplinary team led out of NASA’s Langley Research Center which has the responsibility for governance of the nation’s multi-decadal Earth Radiation Budget Climate Data Record, ERB CDR.  The Science Data Processing System which produces the ERB-CDR is highly complex, producing Level one through Level 4 products.  The system ingests data from 15 different instruments on 9 different spacecraft (5 GEO and 4 LEO) as well as other ancillary information, producing 25 different products with consistent TOA, Surface, and atmospheric radiative fluxes, cloud and aerosol properties on multiple spatial and temporal scales.  Spatial scales vary from instantaneous/pixel (25 km), 1-deg grid, zonal, regional and global means while temporal scales vary across instantaneous, hourly, 3 hourly to monthly scales.  Accuracy and precision values vary across the various spatial and temporal scales, with the long-term goal of measuring decadal trends of better than 0.3 W/m^2 per decade.

 

Instrument calibration and precision, as measured through the post-launch protocols, is one of many considerations that drive the decision to reprocess, others include, but are not limited to validation and instantiation of new algorithms across all levels of products, outside teams reprocessing the products we ingest, the launch of new instrumentation to replace operational weather imagers on Geo satellites, updates to processing hardware, and of course resource availability.  These all need to be managed/considered in order to provide the global community products of sufficient accuracy and precision on a time-scale which allows continued advancement and discovery of key scientific questions such that policy makers may make informed decisions.

 

This presentation will highlight the processes and protocols the Earth Radiation Budget Science Team utilizes to guide reprocessing decisions, identifying lessons learned and best practices.
ENSO modulates the variability of ice core δ18O in the central Tibetan Plateau
Authors: Gao Jing , Yao Tandong , Wu Guangjian , Risi Camille
Published: March 2020

The El Nino-Southern Oscillation (ENSO) drives interannual variability of rainfall, ecosystems and floods in many parts of the world. Climates in the Tibetan Plateau (TP) called as the “water tower” may be impacted by ENSO, but the character of ENSO impact and its mechanism are still not well understood. Here we present the isotopic profiles (δ18O) from a new Zangsegangri (ZSGR) ice core drilled in 2013 in the central TP covering 200 years to understand the ENSO impact on the TP climate. The imprint of ENSO is evidenced at annual scale as recorded in ice core. This ice core δ18O record also reveal contributions of south/north moisture sources change with the transition of El nino/La nina events which are triggered by the tropical sea surface temperature, associated with the change of convections along the moisture transport paths. These rapid changes lead to the variation of ZSGR ice core δ18O, namely El Nino events result in lower δ18O in the ZSGR ice core record. The mechanism of ENSO impact on the ZSGR ice core δ18O are quantified with LMDZiso model. The significant impact of ENSO activity on the Tibetan ice core record during the past centuries implies the importance of ENSO in land surface processes in the TP.
A forecast-informed reservoir operation framework incorporating climate indices
Authors: Yang Guang , Block Paul
Published: March 2020

Incorporating streamflow forecasts into reservoir management can often lead to improved operational efficiency. Large-scale climate variables and indices – in addition to local hydrologic variables – may also provide valuable information for reservoir operations given their limitate relationship with streamflow. A new tree-based machine learning approach for updating reservoir operating rules conditioned on large-scale climate indices is proposed by selecting the most suitable reservoir decision-making pattern for each year. Multiple types of reservoir operating rules can be extracted from the historical streamflow data with different hydrological (e.g., wet and dry) conditions. Their performance can be recorded and correlated with climate indices by using a decision-tree classification model, and then the rules with the best performance conditioned on a given climate index value can be selected for reservoir operations. A case study of reservoir operations for the Grand Ethiopian Renaissance Dam (GERD) on the Blue Nile River demonstrates that the proposed tree-based reservoir operation framework can accurately select suitable decision-making rules both for normal and forecast-informed reservoir operations. Notably, incorporating May Nino 4.0 values into GERD reservoir operations can increase power generation during flood seasons, especially in extreme years.
Analysis of the lightning flashes associated with very large and luminous sprites in Western Europe
Authors: Soula Serge , Mlynarczyk Janusz , Pizzuti Andrea , Pedeboy Stéphane , Gonneau Eric , Gomez Kuri Zaida , van der Velde Oscar , Montanya Joan , Farges Thomas , Fullekrug Martin , Bennet Alec , Boyer Daniel , Cavaillou Alain
Published: March 2020

During the last decade, a large number of sprites were observed thanks to low-light video cameras located in southern France, especially at Pic du Midi (2877 m) in the Pyrénées mountain range and at the Albion Plateau (1000 m) in the south-east of France. Sprites are Transient Luminous Events (TLEs) consisting of streamer discharges, that develop at the base of the ionosphere and whose structure, size and brightness are very variable according to the density and the dynamics of these streamers. The largest type is called jellyfish or « A-bomb » sprite, and it corresponds generally to a very impulsive return stroke. Among more than 3000 sprite events in the database, we selected a few cases with large size and very strong light emission. The goal is to determine the characteristics of the flashes that produced them and the storm context in which they occurred. Thus, we analyse the video imagery, the thundercloud structure, the current moment waveform of the lightning strokes, the radiations at various frequencies from the lightning flash. We show that such very bright sprites can occur above thunderstorms at any period of the year. The favourable conditions for their production seem to be stationary thunderstorms and one case of storm produced five of them. All cases of these sprite events are associated with a halo and they are produced with a very short delay after strong positive cloud-to-ground strokes. The peak current of these strokes is about 150 kA in average and their iCMC values can reach close to 2000 C km. The leader processes and the stroke location in the thundercloud are analysed in detail for some cases.
Heavy rainfall and flood risk assessment method considering the future climate change
Authors: Yamada Tomohito , Hoshino Tsuyoshi
Published: March 2020

Existing flood control plans have been implemented based on rainfall estimated from observation data. However, we have data from the past several decades. Thus, it is not enough to project future extreme events from existing observation data. Therefore, Japan has been created huge ensemble of high-resolution climate model simulation based on the laws of physics. The data consist of past and future climate situations (past climate: total 3,000 years, 4 K warmer climate: total 5,400 years). It has enabled to quantitatively evaluate the probability of heavy rainfall and flooding on the future 4K-warmed earth.

Moreover, we apply the statistical theory of extreme value to evaluate the probability of heavy rainfall and flooding in the future. The results from statistical method is equivalent to the results from the huge ensemble data from climate model. It supports Japanese governments in formulating and carrying out their adaptation plans.