bluuebunny/crossref_metadata_2025 huggingface dataset:
Seismic strengthening of diatom-rich sediments: A comparison of slope sediments from Chilean lakes and the Japan Trench margin
Authors: Moernaut Jasper , Wiemer Gauvain , Wu Ting-Wei , Molenaar Ariana , Kopf Achim , Strasser Michael
Published: March 2020

Earthquakes are a main trigger of subaqueous landslides and surficial sediment remobilization at ocean margins and lake basins. If the earthquake loading is insufficient to lead to sediment failure, the subsequent dewatering and inherent compaction may enhance the shear strength of sedimentary slopes, a process termed „seismic strengthening“, which is believed to be especially relevant for the upper 10s of meters. This mechanism has been suggested to explain the observed paucity of submarine landslides on active margins when compared to the short recurrence of strong earthquakes in such settings. However, only few field studies were dedicated on this topic and little is known about which settings are especially prone to seismic strengthening.

Here, we present geotechnical data from diatom-rich sedimentary slopes in Chilean lakes and at the Japan Trench margin. We use the overburden-normalized undrained shear strength as an indicator of consolidation state. In Chile, this data is derived from in-situ dynamic cone penetrometer measurements, whereas the Japan data is obtained by lab vane shear tests on sediment cores. Both settings show extremely elevated shear strength of about ~5-10 times higher than expected for normally-consolidated sediment in the upper meters of a sequence. Significant overconsolidation is confirmed by one-dimensional compression tests, providing overconsolidation ratios of ~2-8 (Chilean lakes) and 4-9 (Japan Trench). For each setting, the shear strength profiles of sites with different sedimentation rates show very similar trends when they are normalized over the sediment age instead of over overburden stress. As older sediments experienced more earthquakes, this apparent age-dependency may form a new argument supporting the hypothesis of seismic strengthening. Following previous lab experiments on mixtures of diatoms and clayey-silt, we postulate that a high susceptibility to seismic strengthening in both settings is caused by the abundance of diatom frustules which are typically characterized by a high particle interlocking and surface roughness. On the Japan Trench margin, biogenic opal forms ~15% in dry weight, and given the hollow structure of diatom frustules, we infer that diatoms take up a considerable space in the in-situ sediment texture. We conclude that seismically active margins with diatom-rich sediments have a reduced susceptibility to submarine landslide hazards.
Effects of hydro-climate periodicity on hydropower production operation
Authors: Hao Shuang , Wörman Anders , Brandimarte Luigia , Riml Joakim
Published: March 2020

Hydropower accounts for almost half of all electricity production in Sweden, while also being the most important energy balancing resource. Nuclear power plants are gradually being decommissioned up to 2045 in Sweden according to the government’s plans. It means there is a need for a dramatic expansion of renewable energy production, especially for hydropower as a balancing resource. The availability of renewable energy fluctuates with the weather, seasons, and between years, which is an important factor for the coordination of renewable energy production.

The aim of this research is to investigate how runoff forecasts affect hydropower production planning when the account is taken to hydro-climatic variations. This problem is studied by using production planning models fed by runoff forecasts that exhibit climate-driven periodicity. Statistical ensemble predictions and receding horizon control are implemented to reveal the effect on the production. Further, we utilize half-a-century long daily hydro-climatological data to runoff forecasts that are aggregated in ensembles particularly reflecting the bi-annual climate periodicity apparent from spectral analysis of the data.

Dalälven River Basin is used as a study case, which is a watershed stretching from western Sweden to the Baltic in the east and which has more than 30 hydropower stations. Four forecast ensemble scenarios have been analyzed out by studying the periodicity of discharge data in Dalälven River Basin. According to the seasonal and two-year periodicity, the four scenario ensembles are defined as: a) Odd year, wet month; b) Even year, dry month; c) Odd year, dry month; d) Even year, wet month. [A1] A large-scale optimal hydropower production model was built in MATLAB, in order to simulate hydropower production in Dalälven River Basin. It includes 13 reservoirs and 36 hydropower plants, and applies the sequential-quadratic-programming (SQP ) as the optimization method. Receding horizon control is embedded into the optimal production programming, which can correct the systematic error. The historical data shows that the one-year-long sampling has a consistent biannual periodicity, with wet and dry years of different strength depending on the start month of the data selection in the year. It indicates the discharge data selection start from November and December gives the most dramatic effect on periodicity, while starting from May and July have a lower impact. Dynamic programming of hydropower production shows for both dry and wet runoff conditions that matching the forecast ensemble with the right phase of the actual climate conditions has a significant effect on the production profit.
Damming effect on carbon processing in a subtropical valley-type reservoir in the upper Mekong Basin
Authors: Lin Lin
Published: March 2020

Damming rivers has been identified as one of the most intense artificial perturbations on carbon transportation along the river continuum. To quantify the damming effect on the riverine carbon flux in the upper Mekong River, seasonal carbon fluxes were monitored in a subtropical valley-type reservoir (the Gongguoqiao Reservoir) in 2016. Annually, around 20% of the incoming carbon was sequestered within the reservoir with most of the carbon retention occurring in the rainy season. Since higher rainfalls and water discharge brought large amounts of terrestrial carbon into the reservoir in summer, the concentrations of dissolved organic carbon (DIC), particulate inorganic carbon (PIC) and particulate organic carbon (POC) in the topwater show significant decreasing trends from the river inlet to the outlet (p<0.01). During the cooler dry season (winter), however, the damming effect was much weaker. Precipitation of PIC owing to the alkaline environment and decelerated flow velocity contributed over half of the carbon retention in the reservoir. Correlation between suspended sediment concentration and carbon concentrations reveals that heavy sedimentation also resulted in the sequestration of particulate carbon. Yet the damming impact on the flux of dissolved organic carbon (DOC) was relatively weak due to the short water retention time and refractory nature of allochthonous carbon. The anti-season operation of the dam allowed little time for the decomposition of the incoming DOC in the rainy season. The differentiation processing of the carbon flow significantly increased the dissolved carbon proportion in the outflow. The dams could be acting as filters and the effect might be exacerbated in the cascading system. Accumulation of dissolved organic carbon possibly can accelerate eutrophication processes in the downstream reservoirs and thus altered the aquatic carbon dynamics in the downstream river channels. 
Assessment of prediction skill for land water storage in CMIP5 models based on GRACE satellite observations
Authors: Jensen Laura , Eicker Annette , Stacke Tobias , Dobslaw Henryk
Published: March 2020

Reliable predictions of terrestrial water storage (TWS) changes for the next couple of years would be extremely valuable for agriculture and water management. Decadal predictions have already shown to be meaningful for predicting e.g. sea surface and air temperature, but have not yet been intensively investigated regarding TWS. Here we evaluate decadal hindcasts of TWS related variables from an ensemble of five CMIP5 (Coupled Model Intercomparison Project Phase 5) climate models against a TWS data set that is based on GRACE (Gravity Recovery And Climate Experiment) satellite observations.

As the overlap time span of 9 years for the model time series and GRACE observations is not long enough for a robust comparison, we also use a GRACE-based reconstruction of TWS utilizing precipitation and temperature data sets (Humphrey and Gudmundsson, 2019) available back to the year 1900. Thus we are able to compare the full 41 year (1970-2011) time span covered by CMIP5 decadal predictions to the TWS reconstruction. Correlations and root mean squared deviations (RMSD) are calculated for yearly global averages and for individual climate zones. Furthermore, we derive global maps of correlations and RMSD.

We find that at least for the first two prediction years the decadal model experiments clearly outperform the classical climate projections, regionally even for the third year. However, the spread among the models is large and absolute similarities between model output and GRACE TWS reconstructions are quite low.

We also perform a preliminary skill assessment for the first CMIP6 decadal hindcasts publicly available, finding a slightly reduced skill for the first forecast year in comparison to the CMIP5 models, while for the second forecast year an improvement is seen. This result is generally encouraging, but requires confirmation as soon as more CMIP6 decadal hindcasts become available.

Humphrey, V., Gudmundsson, L., 2019. GRACE-REC: a reconstruction of climate-driven water storage changes over the last century. Earth System Science Data Discussions 1–41. https://doi.org/10.5194/essd-2019-25
Geoheritage and Geotourism in the cities: the case of Santiago del Teide (Tenerife, Spain)
Authors: Hernández William , Dóniz-Páez Javier , Przeor Monika , Pérez Nemesio , Hernández Pedro A.
Published: March 2020

The Canary Islands are one of the main “sun and beach” tourist destinations in the world. As an example, Tenerife received in 2018 more than five million tourists. Even so, on the island there are some destinations that are experiencing a decrease in the touristic afflux. With the aim of avoiding the decline of these destinations initiatives have been raised to promote new touristic products and experiences as result of diversify the leisure offer of the island. Within the variety of new products, urban geotourism is one of those new and alternative modalities that may increase the touristic offer of Tenerife. Urban geotourism aims at exploiting the geographical and natural elements (volcanoes, cliffs, beaches, ravines, etc.), that have not been wiped out by the urban growth and transformation processes. Urban geotourism involves also cultural heritage (churches, hermitages, cemeteries, houses, squares, etc.) and the urban layout itself.

 

The aim of this work is to propose an urban geotourism itinerary through the historical centre of Santiago del Teide (Tenerife, Canary Islands, Spain). For this purpose, we selected places and elements that are directly or indirectly associated with the monogenic basaltic eruptions of the Chinyero (1909 AD) and the Bilma Mountain volcano (3,000 years BC). Santiago del Teide is a municipality located at the west of Tenerife with an area of 52.21 km2 and a population of 10,755 inhabitants. The municipality can be divided into two large areas: the coast dedicated to “sun and beach tourism” and mid-elevation areas dedicated mainly to agricultural activities and hiking tourism associated with flowering almond trees. The documented methodology consists of making an inventory of the land forms and processes related to the geomorphological features present in the historical centre and its surroundings. This inventory comprises also natural elements visible in the architecture of the town and allowed classifying and estimating the valuable element of the geoheritage. This identification and selection are based on the variety of inventoried resources, on the possibilities it offers and on its geographical distribution. Twelve places of natural heritage (Way of the Virgin of Lourdes and Mountain Bilma) and cultural relevance (Church of San Francisco Rey, Hermitage of Santiago Apostle, El Calvario, Casona del Patio, CEI Chinyero, Alley of the Virgin, Eras of Rodríguez Guanche Street, Crescent Square, San Francisco Cemetery and Cemetery Road, Queen's Street, Santiago del Teide City Hall, La Grama Quarry, Vicente Febles PR and the Arribas Valley) of the city were selected to design a geotouristic itinerary with a length of about 8 km and requiring about 5 hours walking.
Understanding and modeling the scaling spectrum of climate
Authors: Ellerhoff Beatrice , Rehfeld Kira
Published: March 2020

Modeling climate dynamics in a comprehensive way and improving its predictability in a warming world requires a better understanding of climate variability across scales. However, fundamental mechanisms governing variability on long timescales are still poorly understood.
The temporal evolution of climate can be inferred from paleoclimate records, such as ice cores or marine sediments. Power spectra serve to quantify changes of variability over time and to identify timescales associated with periodic or quasi-periodic processes. The spectra of surface temperature not only comprise spectral peaks, but also reveal a continuous part. It was shown that the background continuum exhibits a scale break, following different power-laws on monthly to decadal versus millennial to longer periods. It is yet mostly unexplained, how these power-laws arise and whether a coupling between different timescales can be deduced from it. We study these questions by comparing and applying spectral analyses to paleoclimate records and climate model simulations for the Quaternary. The data is used to reconstruct the temperature spectrum on diurnal to astronomical timescales. We extend previous studies by including climate responses, such as δ18O and temperature records, and climate forcings, for example, insolation and volcanic forcing. The emergence of scaling in temperature variability is analyzed by successively accessing the background continuum. Higher order spectra test for correlations between forcings and responses. In particular, the bispectrum and bicoherence is computed for statistical processes and evaluated for temperature records in order to study whether the scaling properties are related to energy transfers between different states in time. We elaborate the potential of these methods to reveal dynamical processes governing the continuous spectrum of surface temperature.
Statistical investigation of gravity wave propagation in the Czech Republic and above
Authors: Chum Jaroslav , Podolska Katerina , Rusz Jan , Base Jiri
Published: March 2020

Propagation of gravity waves (GWs) is studied in the troposphere and thermosphere/ionosphere. The investigation of GW propagation in the troposphere is based on measurements by large scale array of absolute microbarometers with high resolution that is located in the westernmost part of the Czech Republic. On the other hand, the propagation of GWs in the thermosphere/ionosphere is observed remotely, using multi-frequency and multi-point continuous HF Doppler sounding system operating in the western part of the Czech Republic. The reflection heights of sounding radio waves of different frequencies are determined from ionospheric sounder, located in Pruhonice in the vicinity of Prague. Propagation velocities and directions are in both cases calculated from time/phase delays between signals recorded at different locations. The investigation of propagation of GWs in the ionosphere is performed in three dimensions as the observation points (reflection points of radio signals) are separated both horizontally and vertically. It is shown that GWs in the ionosphere usually propagate with wave vectors directed obliquely downward, which means upward propagation of energy. In addition, seasonal and diurnal changes of propagation directions were found. Typical propagation velocities of GWs observed at ionospheric heights are much higher (~100 to 200 m/s) than those observed on the ground (several tens of m/s).        
A new working group on the Regional Assessments of Glacier MAss Change (RAGMAC)
Authors: Zemp Michael , Braun Matthias H. , Gardner Alex S. , Wouters Bert , Moholdt Geir , Hock Regine
Published: March 2020

Retreating and thinning glaciers are icons of climate change and impact the local hazard situation, regional runoff as well as global sea level. For past IPCC reports, regional glacier change assessments were challenged by the small number and heterogeneous spatio-temporal distribution of in situ measurement series and uncertain representativeness for the respective mountain range as well as by spatial limitations of current satellite altimetry (only point data) and gravimetry (coarse resolution). Towards IPCC SROCC, there have been considerable improvements with respect to available geodetic datasets. Geodetic volume change assessments for entire mountain ranges have become possible thanks to recently available and comparably accurate DEMs. At the same time, advances have been made in processing methods for radar altimetry (CryoSat-2 swath processing), as well as new spaceborne laser altimetry (ICESat-2) and gravimetry (GRACE-FO) missions are in orbit and about to release data products to the science community. This opens new opportunities for regional evaluations of results from different methods as well as for truly global assessments of glacier mass changes and related contributions to sea-level rise. At the same time, the glacier research and monitoring community is facing new challenges related to data size, formats, and availability as well as new questions with regard to best practises for data processing chains and for related uncertainty assessments.

In this PICO presentation, we introduce a new working group of the International Association of Cryospheric Sciences (IACS) on Regional Assessments of Glacier Mass Change (RAGMAC; https://cryosphericsciences.org/activities/wg-ragmac/). The overall goal of this working group (WG) is bringing together the research community that is assessing regional glacier mass changes from various observation technologies and to come up with a new consensus estimate of global glacier mass changes and related uncertainties. The WG is organized in three work packages, two related to different remote sensing technologies (WG1: glaciological and geodetic DEM-differencing methods, WG2: altimetry and gravimetry) and a third that aims at regional comparisons of corresponding results. Participation is open to everybody who is willing to actively contribute to one or several of these work packages.
A new approach that utilizes the GNSS atmospheric delay gradient to monitor front-type heavy rain and typhoon-type heavy rain in 2019 in Japan.
Authors: Arief Syachrul , Heki Kosuke
Published: March 2020

We studied front-type heavy rain and typhoon-type heavy rain in 2019 in Japan, using tropospheric delay data from the dense Global Satellite Navigation System (GNSS) network GEONET. In 2019, based on data from Japan Meteorological Agency (JMA), that front type heavy rain occurred on 26-29 August 2019, and typhoon type heavy rain occurred on 10-13 October 2019.

In this study, we analyzed the behavior of water vapor during heavy rainfall, using tropospheric parameters obtained from a database at the University of Nevada, Reno (UNR). Data sets, including delays in gradient vectors in the troposphere (G), as well as delays in the zenith troposphere (ZTD), are estimated every 5 minutes. Initially, we interpolated G to get grid points. We removed the hydrostatic delay from ZTD to get zenith wet delay (ZWD). In the inversion scheme, we use G at all GEONET stations and ZWD data at low altitude GEONET stations (<100 m) as input. Then we assume that the spatial change in ZWD is proportional to G (Gx = H δZWD /δx, where H is the height of the water vapor scale) and the estimated height of sea-level ZWD at grid points throughout Japan.

We try to justify our working hypothesis that heavy rains occur when the convergence of G and ZWD sea levels is high by analyzing the hourly water vapor distribution on all days in August 2019 and October 2019. We found that both values ​​show a maximum in the period studied when two events heavy rain occurred, i.e., August 27, 2019, and October 12, 2019. Furthermore, we studied the analysis of high time resolution (every 5 minutes) on heavy rain days. The results show that the convergence of G and ZWD sea level rises before rain occurs, and ZWD shows a rapid decline once heavy rain begins.
Tectonic uplift rate in the northern coast of the South China sea: insight from the 10Be exposure dating of marine terrace in southeastern China
Authors: Liang Hao , Zhang Ke , Chen Zihao , Huang Ping , Li Zhongyun , Chen Zhen
Published: March 2020

Along the northern coast of the South China Sea in southeastern China, marine terraces preserved on the widespread Cretaceous granite and recorded both Quaternary uplift and sea-level oscillation. However, because sediments or materials for dating are usually absent, it is difficult to date these paleo-shoreline, which cause great difficulties in early exploration. Fortunately, as great progress on terrestrial cosmogenic nuclide dating, it is possible to yield the exposure age of marine terrace and to calculate the uplift rate along coastal line. This study focuses on two typical sequences of preserved marine terraces lying on the coastal line adjacent the Taiwan Strait in southeastern China. These two sequences of marine terraces (denoted as NZS and HJC site, respectively) both locate on the footwall (uplifting wall) of normal NE-SW trending fault (the Coastal Normal Fault) but on separated blocks subdivided by a normal NW-SE fault. At least 5 terraces and 2 terraces developed on granite at HJC and NZS site, respectively. In particularly, T1 and T3 terrace at HJC site and T1 terrace at NZS site present typical abrasion wave-cut platform with preserved sea stacks. Hence, we collected both profile and surface quarts samples on these well-preserved marine terraces for 10Be exposure dating and yielded exposure ages of 51.0±1.9 ka, 66.2±2.9 ka in T1 and T3 terrace at HJC site, and 87.9±3.5 ka in T1 terrace at NZS site. After subtracting eustatic sea-level changes from the relative sea-level curve, we measure high uplift rates of 1.13 mm/a at HJC site and 1.04 mm/a at NZS site during late Pleistocene. The similar uplift rates in different faulting blocks suggest that surface uplift can be directly linked to NE-SW fault system. Low difference of uplift rate between tow site suggest relative vertical motion of tow faulting blocks could be adjust by NW-SE faults. The regional uplift with high uplift rates is likely corresponding to the major collision between Luzon arc and the Chinese continental margin. However, because the contribution of by isostasy, e.g. surface erosion or ice-volume variation in Quaternary, remains uncertain, the calculated uplift rate maybe overestimated.
Characterization of soil electrical conductivity from Chicken Creek Catchment using deep learning inversion of geophysical data
Authors: Moghadas Davood , Badorreck Annika
Published: March 2020

Exploring hydrological and ecological processes plays a key role in understanding ecosystem developments. In this respect, the constructed catchment, Chicken Creek (Brandenburg, Germany), has been established for fundamental and interdisciplinary scientific research. The main components of the site include a base soil which is followed by a Tertiary clay layer (aquiclude) and sand layer (aquifer) on the top of the domain. In general, the soil mediates many of the processes that govern water resources and quality, such as the partition of precipitation into infiltration and runoff, groundwater recharge, contaminant transport, plant growth, evaporation and energy exchanges between the Earth’s surface and its atmosphere. In this respect, characterization of the soil electrical conductivity (EC) is important, since it is highly correlated with different chemical and physical soil properties.

Low frequency loop-loop electromagnetic induction (EMI) techniques have found widespread application for non-invasive delineation of the subsurface EC structures at different spatial scales. However, successful inversion of EMI data has been a major challenge for decades, due to the non-linearity, non-uniqueness and dimensionality of the inverse problem. Here, a novel approach based on deep learning inversion via convolutional neural networks is proposed to instantaneously estimate subsurface EC layering from EMI data. In this respect, a fully convolutional network was trained on a large synthetic data set generated based on one-dimensional EMI forward model. The trained network was used to find subsurface electromagnetic conductivity images from EMI data measured along two transect from Chicken Creek catchment. Dipole-dipole electrical resistivity tomography data were measured as well to obtain reference subsurface EC distributions down to a 6 m depth. The inversely estimated models were juxtaposed and compared with their counterparts obtained from a spatially constrained deterministic algorithm as a standard code. Application of the deep learning inversion for subsurface imaging from Chicken Creek catchment manifested the accuracy and robustness of the proposed approach for EMI inversion. This approach returns subsurface EC distribution directly from EMI data in a single step without any iterations. The proposed strategy simplifies considerably EMI inversion and allows for rapid and accurate estimation of subsurface electromagnetic conductivity images from multi-configuration EMI data.
Millennial scale monsoon variability in the northeastern Arabian Sea: A multiproxy approach
Authors: Lückge Andreas , Groeneveld Jeroen , Hollstein Martina , Mohtadi Mahyar , Schefuß Enno , Steinke Stephan
Published: March 2020

The Dansgaard-Oeschger oscillations and Heinrich events described in Greenland ice core records are also expressed in the climate of the tropical realm as for instance documented in Arabian Sea sediments. However, little is known about these fluctuations beyond the reach of the Greenland ice cores. Here, we present high-resolution organic- and inorganic geochemical, sedimentological as well as micropaleontological data from two cores retrieved off the coast of Pakistan, extending the monsoon record to the past 200,000 years in millennial scale resolution.

The stable oxygen isotope (δ18O) record of the planktic foraminifera G. ruber shows a strong correspondence to Greenland ice core δ18O, whereas the deepwater δ18O signal of benthic foraminifera (U. peregrina and G. affinis) reflects patterns similar to those observed in Antarctic ice core records. Strong shifts in benthic δ18O during stadials are interpreted to show frequent injections of oxygen-rich intermediate water masses of Southern Ocean origin into the Arabian Sea. Alkenone-derived SSTs vary between 23 and 28°C. Highest temperatures were encountered during interglacial MIS 5. Millennial scale SST changes of 2°C magnitude are modulated by long-term SST fluctuations. Interstadials (of glacial phases) and the cold phases of interglacials are characterized by sediments enriched in organic carbon (TOC) whereas sediments with low TOC contents appear during stadials. Abrupt shifts (50-60 year duration) at climate transitions, such as interstadial inceptions, correlate with changes in productivity-related and anoxia-indicating proxies. Interstadial inorganic data consistently show that enhanced fluxes of terrestrial-derived sediments are paralleled by productivity maxima, and are characterized by an increased fluvial contribution from the Indus River. The hydrogen isotopic composition of terrigenous plant waxes indicates that stadials are dry phases whereas humid conditions seem to have prevailed during interstadials. In contrast, stadials are characterized by an increased contribution of aeolian dust probably from the Arabian Peninsula. Heinrich events are especially dry and dusty, indicating a dramatically weakened Indian summer monsoon and increased continental aridity.

These results strengthen the evidence that North Atlantic temperature changes and shifts in the hydrological cycle of the Indian monsoon system are closely coupled, and had a massive impact on regional environmental conditions such as river discharge and ocean margin anoxia. These shifts were modulated by changes in the supply of water masses from the Southern Hemisphere.
Analysis of CO2 content near Russian cities from OCO-2 satellite measurements
Authors: Nikitenko Anastasia , Timofeyev Yury , Virolainen Yana , Berezin Ivan , Polyakov Alexander
Published: March 2020

The growth of greenhouse gases, primarily carbon dioxide, is the main cause of modern changes in the Earth's climate. At the same time, despite the relatively small area (~ 3%) of the territory of cities, they are responsible for more than 70% of anthropogenic emissions caused by energy supply systems. Therefore, studies of CO2 distributions in cities and surrounding regions, as well as quantitative estimates of urban emissions are an urgent problem.

The paper presents a comparative analysis of CO2 contents and their variations for a number of Russian cities (Moscow, St. Petersburg, Yekaterinburg, Magnitogorsk and Norilsk) on the basis of the OCO-2 satellite measurement data. The studies were carried out using satellite data sets that vary from high to average quality. These ensembles differ for all these cities in the number of measurement days, the total number of CO2 measurements, and the spatial and temporal coverage. For example, a high-quality ensemble covers ~ 90% of the spring and summer months, i.e. provides an opportunity to study CO2 variations in the warm season. The ensemble of measurements with average accuracy more evenly covers the entire year.

The paper studied various characteristics of the column averaged dry-air mole fraction of CO2 (XCO2) for 5 cities, namely, minimal and maximal values, amplitudes of variations, daily average maximal and minimal values, standard deviations, etc. Possibilities of using the OSO-2 data for estimating of anthropogenic emissions in different cities are considered.
Unraveling the upper mantle heterogeneity from integrated multi-observable inversions
Authors: Fullea Javier , Lebedev Sergei , Martinec Zdenek , Celli Nicolas
Published: March 2020

The lateral and vertical thermochemical heterogeneity in the mantle is a long standing question in geodynamics. The forces that control mantle flow and therefore Plate Tectonics arise from the density and viscosity lateral and vertical variations. A common approach to estimate the density field for geodynamical purposes is to simply convert seismic tomography anomalies sometimes assuming constraints from mineral physics. Such converted density field does not match in general with the observed gravity field, typically predicting anomalies the amplitudes of which are too large. Knowledge on the lateral variations in lithospheric density is essential to understand the dynamic/residual isostatic components of the Earth’s topography linking deep and surface processes. The cooling of oceanic lithosphere, the bathymetry of mid oceanic ridges, the buoyancy and stability of continental cratons or the thermochemical structure of mantle plumes are all features central to Plate Tectonics that are dramatically related to mantle temperature and composition.

Conventional methods of seismic tomography, topography and gravity data analysis constrain distributions of seismic velocity and density at depth, all depending on temperature and composition of the rocks within the Earth. However, modelling and interpretation of multiple data sets provide a multifaceted image of the true thermochemical structure of the Earth that needs to be appropriately and consistently integrated. A simple combination of gravity, petrological and seismic models alone is insufficient due to the non-uniqueness and different sensitivities of these models, and the internal consistency relationships that must connect all the intermediate parameters describing the Earth involved. In fact, global Earth models based on different observables often lead to rather different, even contradictory images of the Earth.

 Here we present a new global thermochemical model of the lithosphere-upper mantle (WINTERC-grav) constrained by state-of-the-art global waveform tomography, satellite gravity (geoid and gravity anomalies and gradiometric measurements from ESA's GOCE mission), surface elevation and heat flow data. WINTERC-grav is based upon an integrated geophysical-petrological approach where all relevant rock physical properties modelled (seismic velocities and density) are computed within a thermodynamically self-consistent framework allowing for a direct parameterization of the temperature and composition variables.
The magnitude of temperature increase matters: how will soil organic mineralization respond to future climate warming?
Authors: Zhou Jie , Wen Yuan , Shi Lingling , Dippold Michaela , Kuzyakov Yakov , Zang Huadong , Jones Davey , Blagodatskaya Evgenia
Published: March 2020

The Paris climate agreement is pursuing efforts to limit the increase in global temperature to below 2 °C above pre-industrial level. The overall consequence of relatively slight warming (~2 °C), on soil C and N stocks will be dependent on microorganisms decomposing organic matter through release of extracellular enzymes. Therefore, the capacity of soil microbial community to buffer climate warming in long-term and the self-regulatory mechanisms mediating soil C and N cycling through enzyme activity and microbial growth require a detailed comparative study. Here, microbial growth and the dynamics of enzyme activity (involved in C and N cycling) in response to 8 years warming (ambient, +1.6 °C, +3.2 °C) were investigated to identify shifts in soil and microbial functioning. A slight temperature increase (+1.6 °C) only altered microbial properties, but had no effect on either hydrolytic enzyme activity or basic soil properties. Stronger warming (+3.2 °C) increased the specific growth rate (μm) of the microbial community, indicating an alteration in their ecological strategy, i.e. a shift towards fast-growing microorganisms and accelerated microbial turnover. Warming strongly changed microbial physiological state, as indicated by a 1.4-fold increase in the fraction of growing microorganisms (GMB) and 2 times decrease in lag-time with warming. This reduced total microbial biomass but increased specific enzyme activity to be ready to decompose increased rhizodeposition, as supported by the higher potential activitiy (Vmax) and lower affinity to substrates (higher Km) of enzymes hydrolyzing cellobiose and proteins cleavage in warmed soil. In other words, stronger warming magnitude (+3.2 °C) changed microbial communities, and was sufficient to benefit fast-growing microbial populations with enzyme functions that specific to degrade labile SOM. Combining with 48 literature observations, we confirmed that the slight magnitude of temperature increase (< 2 °C) only altered microbial properties, but further temperature increases (2-4 °C) was sufficient to change almost all soil, microbial, and enzyme properties and related processes. As a consequence, the revealed microbial regulatory mechanism of stability of soil C storage is strongly depended on the magnitude of future climate warming.
Which communication for higher education in scientific disciplines?
Authors: Vitagliano Eleonora , Di Maio Rosa , Calcaterra Domenico
Published: March 2020

Teaching, researching, knowledge transfer and innovation are important drivers of the development of any Country, provided by higher education in humanities, e.g. social and political sciences or clinical medicine, as well as in science and technology. In Europe these items correspond to the heart of a strategy, which aims to enforce a more inclusive, cohesive and competitive continent. Sometimes, science teaching fails because educational programs do not satisfactorily meet social needs, or research does not achieve innovation targets since it is not enough social-impacting. Scientific reductionism favours the individual point of view rather than shared perspectives, which integrate different disciplines and better answer to real problems. Many researchers, highly specialized in their knowledge fields, often transfer clear scientific concepts but unrelated to life or social and ethical values. Moreover, teaching today uses increasingly advanced tools to improve active learning, placing great trust in technology and forgetting the basics of good communication, which lies in the skills of communicator, his authenticity, his sincere interest in the listener’s growth. Following teaching experiences gained with a scientific communication course realised in the last two years at the Polytechnic and Basic Sciences School (Federico II University of Naples, Naples, Italy), we propose a distinction between science popularization and science communication, which establishes interesting guidelines for dealing with the complex interaction between higher education and society's needs. We have recovered the basic of communication skills, highlighting the importance of the sender-receiver relationship and strengthening the idea that effective communication occurs when receiver and sender simultaneously grow: the former improves his knowledge and his ability to choose, and the second one changes himself as an effect of the receiver’s reaction. Achieving effective communication in education is primarily a matter of taking care of the interpersonal relationship. Finally, we demonstrate that there is not only one way to communicate, but there are many approaches, depending on the peculiar relationship between sender and receiver.
The Detection and Consequences of Coherent Electromagnetic Plasma Waves: Prediction of Rapid L = 2-3 Electron Slot Formation
Authors: Tsurutani Bruce , Park Sang A , Pickett Jolene , Lakhina Gurbax , Sen Abhijit
Published: March 2020

Low frequency (LF) ~22 Hz to 200 Hz plasmaspheric hiss was studied using a year of Polar
plasma wave data occurring during solar cycle minimum. The waves are found to be most intense in the noon and early dusk sectors. When only the most intense LF (ILF) hiss was examined, they are found to be substorm dependent and most prominent in the noon sector. The noon sector ILF waves were also determined to be independent of solar wind ram pressure. The ILF hiss intensity is independent of magnetic latitude. ILF hiss is found to be highly coherent in nature. ILF hiss propagates at all angles relative to
the ambient magnetic field. Circular, elliptical, and linear/highly elliptically polarized hiss have been detected, with elliptical polarization the dominant characteristic. A case of linear polarized ILF hiss that occurred deep in the plasmasphere during geomagnetic quiet was noted. The waveforms and polarizations of ILF hiss are similar to those of intense high frequency hiss. We propose the hypothesis that ~10–100 keV substorm injected electrons gradient drift to dayside minimum B pockets close to the magnetopause to generate LF chorus. The closeness of this chorus to low altitude entry points into the plasmasphere will minimize wave damping and allow intense noon‐sector ILF hiss. The coherency of ILF hiss leads the authors to predict energetic electron precipitation into the midlatitude ionosphere and the electron slot formation during substorms. Several means of testing the above hypotheses are discussed.
 
References
[1] Tsurutani, B.T., S.A. Park, B.J. Falkowski, J. Bortnik, G.S. Lakhina, A. Sen, J.S. Pickett, R. Hajra, M. Parrot, and P. Henri (2020), Low frequency (f < 200 Hz) Polar plasmasheric hiss: Coherent and intense, J. Geophys. Res. Spa. Phys., in press. 
Application of hyper-resolution hydrological modeling for water resources decision making
Authors: Wood Eric , Vergopolan Noemi , Lin Peirong , Pan Ming
Published: March 2020

Managing water resources and basin reclamation requires hydrological data across a set of scales.  Unfortunately, in many areas the in-situ data is sparse, or not made available to water managers.  With NASA, ESA and Chinese satellites, their data can potentially be merged with in-situ gauge data.  Doing so results in a number of research challenges: 1. Satellite data based on microwave sensors (e.g. L-band sensors from SMAP or SMOS) results in coarse resolution (~35-50 km) making the data difficult for management; (ii) Satellite data from instruments like LandSat (~90m) suffers from cloud contamination.  New satellites improve resolution but still suffer cloud contamination; (iii) Precipitation (along with radiation) falls between these two spectrums, and its fast dynamics can impact water management decision making; (iv) Topographic and soil characteristics, which govern the runoff from the land to rivers; and (v) river flows that are a water source for drought and a site for reservoirs.

In this talk I will present a new land surface model (HydroBlocks) that we run at a 30m resolution at regional to continental scales.  The water is transmitted to hyper-resolution streams for which we have extracted ~2,900,000 reaches.  Visualization of the models will offer the listener the impact of moving to these scales; and the data needed for water resources management of river basins.
21st century trends in stratosphere-to-troposphere transport
Authors: Abalos Marta , Orbe Clara , Kinnison Douglas , Plummer David , Oman Luke , Jöckel Patrick , Morgenstern Olaf , Garcia Rolando , Zeng Guang , Stone Kane , Dameris Martin
Published: March 2020

One of the key questions in the air quality and climate sciences is how will tropospheric ozone concentrations change in the future. This will depend on two factors: changes in stratosphere-to-troposphere transport (STT) and changes in tropospheric chemistry. Here we aim to identify robust changes in STT using simulations from the Chemistry Climate Model Initiative (CCMI) under a common climate change scenario (RCP6.0). We use two idealized stratospheric tracers implemented in the models to examine changes in transport. We find that the strengthening of the shallow branch of the Brewer-Dobson circulation (BDC) in the lower stratosphere and of the upper part of the Hadley cell in the upper troposphere lead to enhanced STT in the subtropics. The acceleration of the deep branch of the BDC in the NH and changes in eddy transport contribute to increase STT at high latitudes. In the SH, the deep branch does not accelerate due to the dynamical effects of the ozone hole recovery.
Projecting the effect of climate-change-induced increases in extreme rainfall on residential property damages
Authors: Pastor Jacob , Noy Ilan , Sin Isabelle , Sood Abha , Fleming-Munoz David , Owen Sally
Published: March 2020

New Zealand’s public insurer, the Earthquake Commission (EQC), provides residential insurance for some weather-related damage. Climate change and the expected increase in intensity and frequency of weather-related events are likely to translate into higher damages and thus an additional financial liability for the EQC. We project future insured damages from extreme precipitation events associated with future projected climatic change. We first estimate the empirical relationship between extreme precipitation events and the EQC’s weather-related insurance claims based on a complete dataset of all claims from 2000 to 2017. We then use this estimated relationship, together with climate projections based on future GHG concentration scenarios from six different dynamically downscaled Regional Climate Models, to predict the impact of future extreme precipitation events on EQC liabilities for different time horizons up to the year 2100. Our results show predicted adverse impacts vary over time and space. The percent change between projected and past damages—the climate change signal—ranges between an increase of 7% and 26% by the end of the century. We also give detailed caveats as to why these quantities might be mis-estimated. The projected increase in the public insurer’s liabilities could also be used to inform private insurers, regulators, and policymakers who are assessing the future performance of both the public and private insurers that cover weather-related risks in the face of climatic change.
Comparison on the failure process and mechanism between a debris flow and a landslide dam
Authors: Chen Huayong , Cao Chunran , Chen Xiaoqing , Chen Jiangang
Published: March 2020

Besides the numerous artificial dams, there are some other kind of dams distribute such as the glacier dams, moraine dams, landslide dams, and the debris flow dams in China. Especially, the landslide dams and debris flow ones widely distribute in southwest of China after the M8.0 Wenchuan earthquake. Much attention has been paid to the formation, stability, breach process, and the peak discharge prediction of a landslide dam. However few achievements are obtained on the debris flow dams even if the failure of a debris flow dam has posed great threat to the property and life of residents downstream. In this paper, based on the main difference between a landslide and debris flow dam, experiments were conducted by considering different clay content, the initial water content, and incoming water flow. It indicated that the failure duration of a debris flow dam was about 1.60 times as long as that than that of a landslide dam. The peak discharge at the debris flow dam breach was 5.38 L/s. However, the peak discharge at the landslide dam was 7.50 L/s, which was 1.39 times as big as that of a debris flow dam. Finally, by modifying the existing critical initialization condition for the landslide dams, the critical initialization condition for a debris flow dam was proposed.
Importance of shaded leaf contribution to the total GPP of high latitude ecosystems: evaluation of MODIS GPP
Authors: Chen Bin , Arain Altaf , Chen Jing , Wang Shaoqiang , Mo Gang , Liu Jane
Published: March 2020

The Moderate Resolution Imaging Radiometer (MODIS) is a primary instrument in the NASA Earth Observing System (EOS) which was designed for monitoring global terrestrial vegetation. MODIS provides global estimates of 8-day mean gross primary productivity (GPP) at 1-km spatial resolution. In this study, the MODIS GPP algorithm using light use efficiency (LUE) approach and the Integrated Carbon-Canadian Land Surface Scheme (IC-CLASS) based on Farquhar photosynthetic model and a sunlit and shaded leaf separation scheme was evaluated against eddy covariance (EC) measured GPP in a variety of ecosystems in Canada. Although GPP simulated by the two models agreed well when they were averaged over Canadian landmass, there were systematic differences between them in spatial distribution patterns. These differences were due to inherent shortcomings of the LUE modeling approach. When a constant maximum LUE value is specified for each biome type, this simplification cannot appropriately deal with the shaded leaf contribution to total canopy GPP. When GPP was simulated by IC-CLASS with the separation of sunlit and shaded leaves, the biases were minimized. Compared with daily and annual GPP derived from EC flux data at 7 Fluxnet Canada sites, IC-CLASS performed better than the MODIS GPP algorithm. The differences between IC-CLASS and MODIS GPP were larger in more clumped canopies (i.e. forests), resulting from the increase in the fraction of shaded leaves. Thus, the LUE models should be improved to consider different LUEs in sunlit and shaded portions of the canopy for their effective and reliable estimation of GPP at regional scale.