bluuebunny/crossref_metadata_2025 huggingface dataset:
Satellite Microwave TC Warm-core Retrieval for a 4D-Var Vortex Initialization Using a Nonhydrostatic Axisymmetric Model with Convection Accounted for
Authors: Zou Xiaolei , Tian Xiaoxu
Published: March 2020

A recently further refined hurricane warm core retrieval algorithm is applied to the NOAA-20 and S-NPP Advance Microwave Temperature Sounder (ATMS), the Advanced Microwave Sounding Unit-A (AMSU-A) and the Fengyun-3D (FY-3D) microwave temperature sounding instrument (MWTS) brightness temperature observations within and around Hurricanes and incorporated into A four-dimensional variational (4D-Var) vortex initialization (VI) system is developed for a nonhydrostatic axisymmetric numerical model with convection accounted for (the RE87 model). It is shown that the temporal evolution of the ATMS and AMSU-A derived maximum warm core temperature anomalies follow more closely with that of the minimum mean sea level pressure and slightly less closely with the maximum sustained wind, and the radii of the ATMS derived warm cores at 4 and 6 K compared favorably with the 34 kt and 50 kt wind radii during the entire life span of Hurricane Irma in 2017. The vertical extend of the warm core toward the lower levels increases with increasing intensity when Irma experiences a strong intensification due to an enhanced latent heat release associated with diabatic processes. The multi-polar-orbiting operational meteorological satellites can well capture the TC inner cores’ diurnal cycle with a maximum around midnight. A model fit to satellite microwave retrievals of tropical cyclone (TC) warm-core temperatures from the above mentioned three polar-orbiting satellites and and total precipitable water (TPW) Global Change Observation Mission  – Water Satellite 1 produced a significantly improved intensity forecast of Hurricane Florence (2018) and Typhoon Mangkhut (2018), with more realistic vertical structures of all model state variables (e.g., temperature, water vapor mixing ratio, liquid water content mixing ratio, tangential and radial wind components, and vertical velocity) are obtained when compared with a parallel run initialized simply by the European Centre for Medium-Range Weather Forecasts ERA5 reanalysis.
How Has GPS Velocity Field Changed Along the 1999 Izmit Rupture 20 Years After the 1999 Izmit, Turkey Earthquake?
Authors: Özarpacı Seda , Doğan Uğur , Ergintav Semih , Çakır Ziyadin , Özdemir Alpay , Floyd Michael , Reilinger Robert
Published: March 2020

A seismic gap along the western segment of the North Anatolian Fault, in the Marmara-Izmit region, was identified before the 1999 M7.6, Izmit and M7.4 Duzce earthquakes, so the region along the coseismic fault has been monitored with geodetic techniques for decades, providing well defined pre-, co- and post-seismic deformations. Here, we report new continuous and survey GPS measurements with near-fault (~2 – 10 km to the fault) and far-fault (~50 – 70 km from the fault) stations, including 7 years (2013 – 2019) of continuous observations, and 5 near-fault campaigns (every six months between 2014 – 2016) to further investigate postseismic deformation. GPS observations were processed with the GAMIT/GLOBK (v10.7) GNSS software. We used these observations to estimate the spatial distribution of current aseismic after-slip, along the 1999 Izmit rupture. We also searched for spatiotemporal changes of shallow creep events along the surface trace. With elastic models and GPS observations, we determined a shallow creep rate that reaches a maximum around the epicenter of the 1999 Izmit earthquake of about 12.7 ± 1.2 mm/yr, consistent with published InSAR results. Creep rates decrease both east and west of the epicentral region. Moreover, we show that broad-scale postseismic effects that diminish logarithmically, continue at present. (This study is supported by TUBITAK 1001 project no: 113Y102 and 117Y278)
Testing approaches to simulate drainage from the canopy in interception models
Authors: Grunicke Sandra , Plorin Max , Bernhofer Christian , Queck Ronald
Published: March 2020

Drainage from the canopy is one of the sub-processes described in conceptual interception models. In theory, this refers to rainfall water that is temporally stored on the canopy and starts to drip down, when the canopy is saturated. In most Rutter-type models, storage in the canopy is described as a single linear storage (in multilayer models as a storage cascade) from which the drainage occurs after a saturation value is reached. For a precise simulation of the timing and amount of canopy drainage, this approach appears to be insufficient. E.g., with large time-steps and highly filled storage, drainage rates can become larger than the precipitation intensity, leading to a negative storage.

In our study, we present a review of different approaches to simulate drainage according to literature. We test those approaches using the interception model CanWat, which allows temporally and spatially resolved simulations of the relevant processes. CanWat relies on a vegetation model derived from terrestrial laser scans for a detailed description of the stand. CanWat is written in R language allowing to process multi-annual time series for a study area up to 1 km² with a spatial resolution of 1 m3 on a PC. For validation purposes, we use rain events that are available from long-term continuous measurements of interception in a spruce stand (mainly Picea abies; a continuous flux site since started within EUROFLUX in 1996) within the Tharandter Wald Southwest of Dresden.

We outline benefits and limitations of each approach and evaluate which one best fits the needs for a precise simulation of the timing and amount of canopy drainage. The implementation and refinement of the most suitable drainage simulation approach into CanWat is part of the overall attempt to improve the model description of the interception process being the focus of a German Science Foundation (DFG BE-1721/23-1) interception project.
Tracking the development of seismic fracture network by considering the fault rupture method
Authors: Shirzad Taghi , Lasocki Stanisław , Orlecka‐Sikora Beata
Published: March 2020

 In Enhanced Geothermal Systems pressurized injections play a role in developing fracture networks and enhancing the water transmissivity. However, the fractures may also coalesce into undesired pathways for fluid migration to enable the fluids to reach pre-existing faults. The properties of observed seismicity can shed some light on the fracture network development and from the standpoint of the possibility to form such undesired pathways. However, to reach this goal the seismic events should be well parameterized. In particular, the information on fault plane mechanisms is essential, which is often not readily accessible. In this study, we use the rupturing process with an accurate P-wave velocity model, which is obtained by the first arrival P-wave tomography approach, to compensate for an eventual lack of source mechanisms of micro-events. For this purpose, four characteristics of the sources (final/average displacement on the fault, the dimension of fault, rupture velocity and particle velocity) can be considered. A 3D model is defined around the hypocenter of each event, so that the size of this model directly depends on the event magnitude. After calculating the arrival time of the selected phase (e.g., P, S, p or s) for each station, all waveforms are then aligned, and stacked by different stacking (e.g., phase weight, Nth-root) methods. By considering the maximum amplitude of the stacked waveform which is stimulated by each grid, the rupturing plane and the average velocity of rupturing can be obtained. This information of source can be replaced by the double-couple mechanism to investigate the fractures linking and tracking.

This work was supported under the S4CE: "Science for Clean Energy" project, which has received funding from the European Union’s Horizon 2020 research and innovation program, under grant agreement No 764810.
Tracing terrestrial organic matter in surface sediments in Laptev Sea and East Siberian Sea: a Rock-Eval pyrolysis approach
Authors: Gershelis Elena , Kashapov Roman , Ruban Alexey , Grin'ko Andrey , Dudarev Oleg , Shakhova Natalia , Semiletov Igor
Published: March 2020

The East Siberian Arctic shelf (ESAS), the world’s largest continental shelf, receives substantial input of terrestrial organic carbon (TerrOC) both from increasing river discharge and from amplifying coastal erosion. Increasing TerrOC supply directly affects the Arctic marine carbon cycle, and, therefore, the fate of TerrOC upon its translocation to the Arctic continental margin has been the subject of growing interest in recent decades. Previous studies reported a strong decrease in sedimentary bulk TerrOC and terrestrial biomarkers with increasing distance from the coast during cross-shelf transport with much higher extent of degradation in the ESAS nearshore zone. Despite major progress has been made in estimating TerrOC inputs and quantifying its degradation rates in the Arctic land-shelf system, there are still important pieces insufficiently understood. Rock-Eval (RE) pyrolysis contributes to the traditional geochemical interpretations, based on elemental, isotopic and biomarker analyses and provides additional insight into the distribution, source and degradation state of organic carbon compounds of sedimentary organic matter.

In this study, the analytical approach included the characterization of marine and terrestrial carbon compounds using RE data coupled with organic carbon stable isotope composition. Rock-Eval analyses was performed on over 80 surface sediments samples from the Laptev Sea and western part of the East Siberian Sea collected during Arctic expeditions in 2011-2019. A track of rapidly degrading terrOC in shallow deposits may be traced using the ratios between hydrogen and oxygen indices and from the distribution of labile organic carbon fraction. Our results indicated high content of heavily degraded material with low hydrogen index, high oxygen index and a high content of residual carbon in sediments on the outer shelf of the western Laptev Sea and on the continental slope. Sharp decreasing of oxygen content in the eastern part of Laptev Sea and the western East Siberian Sea marked intensive dilution of degraded carbon with fresher material exported from New Siberian Islands. Furthermore, the RE data indicated a relatively high content of residual carbon (up to 87 %) stored in the studied surface sediments.

This research is supported by Russian Science Foundation, project # 19-77-00067.
Lumped hydrological model for reasonable, long- term predictions of groundwater storage and depletion
Authors: Ejaz Fahad , Wöhling Thomas , Wolfgang Nowak
Published: March 2020

Excessive groundwater pumping due to immense agricultural, industrial and municipal demand poses a major threat of aquifer depletion in many areas around the world. The impact of climate change on the global hydrological cycle has further exacerbated the situation. Accurate and reliable prediction of long-term aquifer balance terms is a key prerequisite to manage groundwater sustainably. To deal with uncertainties of such predictions, lumped (conceptual) hydrological models could help with their computational speed that allows for Monte-Carlo simulation. Compared to more complex models, lumped models are fast, lean on data requirement and capable to quantify uncertainty. However, lumped models are mainly designed to simulate river discharge only, not aquifer storage. Even the standard practice for calibrating lumped hydrological models only includes river discharge, as data on groundwater storage is not directly accessible. In this study, we hypothesize that we can extend the HBV model by additional water budget and groundwater storage terms, and calibrated it on both groundwater storage data and discharge data. Then, we test whether its predictions of groundwater storage levels withstand validation tests. To avoid problems with unavailability of data for calibration and validation in a first proof of concept, we build a virtual reality with a MODFLOW-based model, driven with synthetic weather data over a period of more than 50 years. For rigorous testing, we cast calibration into the framework of Bayesian parameter inference, and validate with metrics that assess the appropriateness of the Bayesian prediction distribution of groundwater storage. We test our idea in the Wairau Plain aquifer, New Zealand. Poor understanding of recharge mechanisms and hence declining groundwater levels are the major hindrance for sustainable groundwater management in our study area. We pay specific attention to river-groundwater exchange processes, to the forecast of aquifer storage dynamics, and to groundwater depletion in a hypothetical, persistent draught. The purpose is to provide a proof of concept whether lumped models can be adapted and made suitable to predict declining groundwater resources up to full depletion, as an uncertainty-aware decision support system for sustainable management.

 
Impact of Climate Change on the Agulhas Bank, South Africa ― a 100 year projection with consequences for the squid fishery
Authors: Asdar Sarah , Roberts Michael J. , Jacobs Zoe , Popova Ekaterina
Published: March 2020

The South and East coast of South Africa is strongly influenced by the warm, fast-flowing Agulhas Current. The Agulhas Bank, a shallow shelf on the southern tip of Southern Africa, is a crucial area for productivity which support fisheries of high economic importance for South Africa.  In this context of climate change, perturbations of this diverse, complex and highly variable marine environment could affect the productivity and lead to dramatic social and economic consequences for the region. To predict potential changes over the eastern and central Bank, we employ a high-resolution global coupled ocean-biogeochemistry model, NEMO-MEDUSA, simulated to year 2099. We find that even though the Agulhas Bank is warming over the next century, primary production does not experience a significant decrease. Additionally, we show that the Agulhas Current might shift its position, with intensification surface current velocity on the Bank hence reducing water retention over the Bank. This change in local circulation over the Bank could have a serious impact on the ecosystem of the region.
A multi-hazard assessment of Europe’s power plants
Authors: Schaefer Andreas , Daniell James , Wenzel Friedemann
Published: March 2020

Power plants are essential for modern life and blackouts are a frequent observation during natural disasters. Thus, assessing the specific hazards for power plant facilities is a crucial component of community risk management. However, multi-hazard assessments are rare and risk studies only rely on independent perils.

For the European power plant sites, a multi-hazard assessment has been taken out considering earthquakes, flood, tornados and lightning. Each peril is considered independently. For each power plant location, return period curves for the relevant impact metrics like ground motion or wind speed have been compiled based on a variety of hazard model inputs. Those curves have been combined to provide threshold exceedance curves for any multi-hazard combination.

The results have been facilitated within a software developed for the H2020 EURATOM NARSIS project (New Approach to Reactor Safety ImprovementS) to allow users to define relevant thresholds for different power plant system components like offsite power generators or the connecting road network. In addition, it allows to explore the site-specific hazard combinations. The tool is based on the Electron development framework.

This study provides a general overview on the multi-hazard situation of Europe’s primary power producers and highlights sites where multi-hazard combinations may lead to infrastructure disruption. The results come with an easy-to-use tool to quickly assess the relevant metrics. It is hoped that these findings can help to increase the overall resilience of the European power network.
CATnews - Rapid Impact Modelling of Earthquakes for Social Media in the 2020s
Authors: Schaefer Andreas , Daniell James , Skapski Jens
Published: March 2020

The public attention to natural disasters increased significantly over the last couple of years. To some extend this can be linked to an increased activity of social media networking both from a scientific, but also informal perspective. For several years, CATnews provides impact metrics for earthquakes and other disasters on social media.

The Rapid Impact Modelling framework used by CATnews uses small-scale high-performance computation methods to quickly provide impact results. Such impacts are measured using the modified Mercalli intensity in case of earthquakes and by quantifying the amount of exposed population for each intensity level. For tsunamis or cyclones, quantitative scales like peak coastal wave heights and wind speeds are used. The resulting impact maps for earthquakes are usually hand calibrated using felt reports and testimonies from the affected locations combining-in with social media crowdsourcing and information from the official agencies. In addition, smart algorithms support the calibration to increase their overall accuracy. The rapid impact maps and metrics have been frequently cited by the media and used also for rapid loss estimation and overall disaster analysis.

Starting from a hobby project, CATnews became a well-received and frequently shared platform for natural disaster information, especially earthquakes, on social media. With more extensions to the platform on the way, it is hoped to become a primary source of information for public science on natural disasters.

In 2020, this will extend to being combined with CATDAT and the Earthquake Impact Database to develop a definitive socioeconomic loss database for earthquakes with a felt intensity archive (as well as tsunami archive) for the current year, and past years.
Application of Grassland Fire Monitoring Based on Himawari-8 Geostationary Meteorological Satellite Data
Authors: chen jie , zheng wei
Published: March 2020

Himawari-8 is the next-generation geostationary meteorological satellite, which is developed by JMA and was been launched in October,2014. As the successor to the MTSAT series,Its spatial resolution, observation frequency and position accuracy are much better than the last generation, so it has large advantage in grassland fire monitoring. In this paper, we presentthe method of fire monitoring self-adaptive threshold based on Himawari-8 data, and takean example of using Himawari-8 data to monitor dynamically the grassland fire located near the border of China in April of 2016. The monitoring results show that the fire lasted about 22 hours, the size of burned area were large than 1500 km2, the longest duration of a fire pixel was about 6 hours. Through analyzing a series fire information from successive  Himawari-8 10 minutes frequency observation,the result shows that the expanding speed of the fire is 5.4 km in the direction from west to east during some duration, which is up to the extent of fast speed fire type,. Using this method, analyzed the dynamic monitoring in the next day and other scattered fire point in different areas, which indicate that this method is universality in fire monitoring and Himawari-8 can be well used to monitor the fire dynamically changing, get the location, area and temperature of the fire, evaluate the expanding speed, estimate the trends of fire development and raise the ability of grass land fire monitoring and early warning.
Lower Yangtze drainage reorganization response to western Pacific Subduction
Authors: Wang Ping , Zheng Hongbo , Wang Yongdong , Wei Xiaochun , Tang Lingyu , Jourdan Fred , Chen Jun , Huang Xiangtong
Published: March 2020

The evolution of the longest river in Asia, Yangtze, provides a spectacular example to understand the Cenozoic interaction between tectonic, climate and surface processes. The oldest Yangtze deposits in southeast China, characterized by thick sequence of unconsolidated gravel, sand and silty clay, referred as “Yangtze Gravel”, has been recently found in its lower reach and dated back to > 23 Ma, indicating a pre-Miocene establishment of a through-going river. However, the link between river reorganization and tectonic evolution has never been well understood. Far-field effects of the Indian–Eurasia collision are often invoked to explain the widespread East Asia lithospheric deformations and the opening of the marginal, as well as the through-going of the large rivers. However,  some geological and geophysical investigations challenge this model and suggest that the Pacific Plate subduction beneath Eurasia plays an much more active role in East Asia lithospheric deformation during the Cenozoic. Here, we study the sedimentology, chronology and provenance of the Yangtze Gravel based on 17 stratigraphic sections exposed along the Lower Yangtze River. Our results indicate a braided alluvial system (Paleo-Lower Yangtze) established since early Miocene across the Jianghan Basin, North Jiangsu Basin and East China Sea Shelf Basin. Compared with the Early Cenozoic red-colored, halite-bearing lacustrine deposits, our results indicate a larger tectonically controlled shift from rifting to post-rift down-warping across these basins. During Early Cenozoic, the initial subduction of Pacific Plate may contribute to the back-arc extension and affect the continental deep interior of East Asia many thousands of kilometers from the subduction margin. During Oligocene to Miocene, the ongoing subduction of the Pacific plate produced a stagnant slab that may have significantly triggered the post-rift subsidence and the connection of these basins. The deposition of the “Yangtze Gravel” reflect the dynamic response of surface processes to western Pacific subduction in East Asia.
Fire activity and Aerosol Optical Depth over PEEX area for the last two decades
Authors: Sogacheva Larisa , Sundström Anu-Maija , de Leeuw Gerrit , Arola Antti , Petäjä Tuukka , Lappalainen Hanna K. , Kulmala Markku
Published: March 2020

The Pan-Eurasian Experiment Program (PEEX) is an interdisciplinary scientific program bringing together ground-based in situ and remote sensing observations, satellite measurements and modeling tools aiming to improve the understanding of land-water-atmosphere interactions, feedback mechanisms and their effects on the ecosystem, climate and society in northern Eurasia, Russia and China. One of the pillars of the PEEX program is the ground-based observation system with new stations being established across the whole PEEX domain complementing existing infrastructure. However, in view of the large area covering thousands of kilometres, large gaps will remain where no or little observational information will be available. The gap can partly be filled by satellite remote sensing of relevant parameters as regards atmospheric composition, land and water surface properties including snow and ice, and vegetation.

Forest fires and corresponding emissions to the atmosphere dramatically change the atmospheric composition in case of long-lasting fire events, which might cover extended areas. In the burned areas, CO2 exchange, as well as emissions of different compounds are getting to higher levels, which might contribute to climate change by changing the radiative budget through the aerosol-cloud interaction and cloud formation. In the boreal forest, after CO2, CO and CH4, the largest emission factors for individual species were formaldehyde, followed by methanol and NO2 (Simpson et al., ACP, 2011). The emitted long-life components, e.g., black carbon, might further be transported to the distant areas and measured at the surface far from the burned areas.

 During the last few decades, several burning episodes have been observed over PEEX area by satellites (as fire counts), specifically over Siberia and central Russia. Fire activity can also be seen in increasing Aerosol Optical depth (AOD) retrieved from satellites, as well as fire radiative power (FRP) calculated using the satellite data. In the current work, we study the time series of the fire activity, FRP and AOD over PEEX area and specifically over selected cities.
Global-scale data-model comparison of the July 2nd, 2019 total solar eclipse’s thermospheric effect
Authors: Aryal Saurav , Evans J. Scott , Solomon Stanley C. , Burns Alan G. , Correira John , Dang Tong , Lei Jiuhou , Jee Geonhwa , Liu Huixin , Wang Wenbin , Eastes Richard W.
Published: March 2020

NASA’s Global-scale Observation of Limb and Disk’s (GOLD) instrument observed the July 2, 2019 total solar eclipse’s effect in the thermosphere from a geostationary orbit above South America. GOLD’s observations of compositional and neutral temperature changes induced by the eclipse are different from the modeled effects. Combined Thermospheric Ionospheric Electrodynamics General Circulation Model (TIE-GCM) and GLobal airglOW (GLOW) modeling of GOLD’s observation is relatively successful in reproducing morphologically changes. However, the model underestimates the compositional changes. GOLD observation show a ΣO/N2 column density ratio enhancement of ~ 80 % near the totality, but the model predicts ~ 10 % enhancement. This indicates that there are inadequacies in current modeling capabilities for thermospheric changes during an eclipse. GOLD’s thermospheric measurements provide an important, new test of the models. We will present detailed data-model comparisons of measurements versus modeling results for the July 2nd eclipse.
Revised chronology of northwest Laurentide ice-sheet deglaciation from beryllium-10 exposure-dated erratics on the western Canadian Shield
Authors: Reyes Alberto , Carlson Anders , Reimink Jesse
Published: March 2020

The timing of northwest Laurentide ice-sheet deglaciation is important for understanding how ice-sheet retreat, and associated meltwater discharge, may have been involved in abrupt climate change and rapid sea-level rise at the end of the last glaciation. However, the deglacial chronology across the western Canadian Shield is poorly understood, with only a handful of minimum-limiting 14C dates and sparse cosmogenic nuclide exposure dates constraining the timing and pattern of northwest Laurentide ice-sheet retreat across >1000 km of ice-sheet retreat to the marine limit west of Hudson Bay. We present cosmogenic 10Be surface exposure dating of glacial erratics at two sites, within a ~160,000 km2 region with no reliable temporal constraints on ice-margin retreat, to directly date the timing of northwest Laurentide ice-sheet deglaciation. Six erratics perched directly on bedrock at a site on the western edge of the Slave Craton have exposure ages between 12.8±0.6 and 12.2±0.6 thousand years ago (ka; ±1sigma). Five erratics on bedrock, sampled at a site 115 km up-ice to the east, yielded exposure ages between 10.8±0.5 and 11.6±0.5 ka. When corrected for decreased atmospheric depth due to isostatic uplift since deglaciation, the error-weighted mean ages for the two sites indicate that the Laurentide ice sheet retreated through this region of the western Canadian Shield between 13.3±0.2 and 11.8±0.2 ka, or at least 1 kyr earlier than inferred from the canonical compilation of minimum-limiting 14C dates for deglaciation and paleo-glaciological models. We tentatively infer a preliminary ice-margin retreat rate of ~0.1 m kyr-1 over this interval spanning much of the Younger Dryas which, compared to earlier estimates, implies a substantially lower volume of meltwater flux from the retreating northwest Laurentide ice sheet at this time.  Additional exposure ages on glacial erratics across this data-poor region are needed for validation of existing deglacial ice-sheet models, which can in turn contribute to comprehensive testing of hypotheses related to northwest Laurentide ice-sheet retreat rate, abrupt deglacial sea-level rise, and potential forcing of associated climate change events.
A sedimentological connectivity approach for assessing on-site and off-site soil erosion control services
Authors: Liu Yu , Zhao Liang , Yu Xiubo
Published: March 2020

Soil erosion, a widely-occurring phenomenon in the terrestrial environment, affects land productivity and infrastructure security negatively both on-site and off-site. Therefore, soil erosion control services (SECS) are one of the most fundamental ecosystem services for human well-being. Although previous SECS assessments elaborate the benefits from preventing on-site soil erosion and soil loss comprehensively, the off-site benefits remain vague. They are usually estimated only through multiplying the capacity of on-site soil erosion prevention by a land-use-based, and spatially consistent, allocation coefficient. The corresponding overestimation, item omission, and inability to represent the spatial heterogeneity of SECS may lead to great uncertainties. In addition, the SECS decay with travel distance is not well represented, because of a neglect of the cascading nature of SECS formation and its delivery. Here, to address these deficiencies, a cascade framework for SECS assessment is developed that incorporates the concept of sedimentological connectivity over the landscape. This approach quantifies both the on-site soil erosion prevention and mitigation of sediment delivery over the landscape, based on an understanding of the cascading nature of soil erosion and sediment delivery, by referring to the framework of WATEM/SEDEM that potentially reveals the sedimentological connectivity over landscape. A monetized valuation of SECS delivered to local communities was derived by employing a land-use based replacement cost technique, which takes cultivated land units as a SECS receiver and conveyer. The approach was applied in a loess catchment located in the middle Yellow River basin, China as a case study. For this watershed, with an area of 54.2 km2, the gross soil erosion reduction was up to 156.93 × 104 t; the reduction of sediment input was 11.28 × 104 t; and the reduction in gross sediment export is up to 181.34 × 104 t. The monetized value delivered to utilized land units was 910.13 × 104 CNY. The approach described provides a tool that specifically addresses the SECSs directly useful to humans, contributes to quantifying the soil erosion control services provided by the landscape, and improves the reliability of evaluating SECS.
Multiple sand bar dynamics in the macrotidal Shinduri beach, west coast of Korea
Authors: Chang Tae Soo , Youn Hyun Ho , Chun Seung Soo
Published: March 2020

Extensive tidal flats and sandy beaches are a typical coastal landform along the macrotidal west coast of Korea. Macrotidal beaches typically with long stretches and the gentle slope, contain often a series of sand bar, parallel to the coastline. Shinduri beach under macrotidal condition in a semi-closed embayment, western coast of Korea, has three to four lines of sand bars on about 500 m stretches of intertidal zone. Interesting feature is the dynamic behaviour of the multiple bars. These bars appear only in summer and disappear dramatically all in winter, which is opposite pattern in common beaches. In order to understand the seasonal dynamics of multiple bars on a macrotidal beach, three years of topographic survey using a VRS-GPS system have been conducted at three-months interval on six transects placed on the beach. In addition, an ADV/ADCP was deployed to collect wave data on a bar. Shinduri beach is a 4 km in length and about 500 m in width. Topographic survey reveals that three to four bars occur only during summer, and disappear suddenly during winter. In response to bar growth and destruction, beach slopes become steeper in winter and gentler in summer. Mean grain sizes show generally shoreward coarsening trend, ranging from 2.0 phi to 2.75 phi. Sediments get coarser in summer, but finer in winter, which are opposite compared to other beaches in the west coast of Korea. Wave data show strong seasonality, high waves in winter and much gentler waves in summer, suggesting the study area experienced by monsoon climate. The opposite pattern of multiple bar dynamics, growth in summer and destruction in winter, is likely associated with strong winter waves, destroying the bars and hence filling the trough of bars, thereby the beaches becoming flat in topography. From spring the bars start to form under normal wave condition. This signifies that local wave condition is more important for maintaining patterns of multiple bars.
Blame it on the Weatherman: How critical is rainfall to geomorphology?
Authors: Skinner Chris , Peleg Nadav , Coulthard Tom , Molnar Peter
Published: March 2020

The geomorphic activity of fluvial systems at any scale is ultimately driven by precipitation often in the form of rain. In numerical models, such as landscape evolution models, an input dataset of rainfall is commonly used to drive the model, often using a coarse spatial and/or temporal averaging. Beyond availability, characteristics of the rainfall data itself are frequently overlooked and the impacts of these on the results of the model not considered. However, landscape evolution models are sensitive to spatial and temporal variations in rainfall data and rainfall observations themselves contain spatial and temporal uncertainties, the nature of which varies between different observation methods.

This presentation synthesises the results of several linked studies highlighting the role rainfall can play in the modelling of geomorphology. First, we examine how the spatial and temporal resolution of the driving rainfall data is applied at influences the model outputs, with more than 100% difference in simulated sediment yields between the coarsest and finest resolutions used. Secondly, the role the source of the rainfall data plays, through comparison of observations from different methods, is explored showing that the uncertainty between the observations propagates non-linearly to simulated sediment yields.

To investigate these sensitivities the CAESAR-Lisflood model was used in combination with the STREAP weather generator to produce high-resolution estimates of rainfall, conditioned by observations, for the longer timescales required for landscape evolution studies. This pairing opened up the opportunity to investigate changes of geomorphic response to future predicted changes to rainfields due to climate change, showing that this is more complex than when considering changes to rainfall volumes alone.
Modelling the electron density distribution in the Io Plasma Torus using Juno radio occultations
Authors: Zannoni Marco , Moirano Alessandro , Gomez Casajus Luis , Tortora Paolo , Durante Daniele , Iess Luciano
Published: March 2020

The innermost galileian moon Io hosts an intense volcanic activity, which ejects about 103 kg/s of gas into Jupiter's magnetosphere. Here these neutrals are ionized by interaction with the background plasma and they are accelerated from keplerian velocity to corotation velocity thanks to Alfvén's theorem. This plasma cloud around the planet (the so-called Io Plasma Torus or IPT) slowly diffuses across Jupiter's magnetic field, but high electron densities (>1000-2000 cm-3) are found between 5-8 RJ.

Juno is travelling along highly eccentric, polar orbits around the planet and flies very close to Jupiter's surface during each perijove. Thus, the radio links used for ground communication and radio science cross the IPT both in the uplink and the downlink leg. Being a dispersive medium, the torus introduces a different path delay on the X/X and Ka/Ka links established between the Ground Station and the spacecraft. Thus, the path delay can be extracted through a linear combination of the two links, and then quantitatively analyzed and fitted to different parametric models of the IPT.

In this work we have used almost all the available Juno radio occultations of the IPT in order to improve an already existing model by introducing both longitudinal and temporal variations of the electron density. To this end, we looked for the 2D Fourier expansion in longitude and time of the parameters of this model with the goal of minimizing the residuals of the fit and pointing out periodicities in the morphology of the torus.
Slope analysis of active fault in volcanic areas using high-resolution DEM based on GIS
Authors: Kawabata Daisaku , Kimura Haruo
Published: March 2020

The movement of active faults due to inland earthquakes often involves surface displacement. In Japan, where many active faults are distributed, fault displacements are often accumulated and reflected on the current topography. For example, in a region where right-lateral strike-slip faults are distributed, it is possible to observe river topography systematically right-lateral strike-slip from the fault. Japan has many volcanoes as well as active faults, but in volcanic areas it is difficult to find evidence of fault activity accumulation in the terrain, and it is difficult to find fault traces on the surface. In this study, we performed geomorphological analysis using high-resolution DEM based on GIS in the southern part of Iwate prefecture where many volcanic rocks are distributed, and examined the relationship between river topography and active faults. The target area is mainly covered by Miocene to Pleistocene volcanic rocks. In this area, despite significant earthquakes occurring since 1896, there is little apparent surface displacement. An Mw 6.9 earthquake with surface displacement occurred in 2008 in this area. In this study, basic topographical measurements such as slope, aspect, dispersion of altitude, and stream density and stream-power indices were analyzed using 5mDEM in the target area. As a result, it was found that the SPI value tends to be higher in the area where surface displacement was observed in 2008. It is necessary to clarify the relationship between fault activity and topography by increasing the target area and conducting watershed analysis using SPI and other indices.
Climate Monitoring SAF: Sustained Generation of Satellite based climate data records
Authors: Schröder Marc , Hollmann Rainer , Trentmann Jörg
Published: March 2020

In recent decades climate variability and change have caused impacts on natural and human systems on all continents. Observations are needed to understand and document these interactions. These observations are increasingly based on remote sensing from satellites which offer global scale and continuous coverage. Only long-term and consistent observations of the Earth system allow us to quantify impacts of climate variability and change on the natural and human dimension. From this understanding one can estimate and eventually predict future states of the Earth system and quantify its vulnerability and resilience to continuing anthropogenic forcing.

Since nearly 20 years, the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) Satellite Application Facility on Climate Monitoring (CM SAF, www.cmsaf.eu) develops capabilities for a sustained generation and provision of Climate Data Records (CDRs) derived from operational meteorological satellites. The ultimate aim is to make the resulting data records suitable for the analysis of climate variability and the detection of climate trends. The product portfolio of the CM SAF comprises long time series of Essential Climate Variables (ECVs) related to the energy and water cycle as defined by the Global Climate Observing System (GCOS). Several data records have been released to the public by CM SAF and new editions of CDRs will be published in the coming years which will extend the time-range and the portfolio. In particular, existing products include, among others, surface and top of the atmosphere radiative fluxes, surface albedo, cloud products, as well as latent heat flux and freshwater flux over the global ice-free oceans. New products related to the following topics are currently developed and provided in near future: global precipitation (ocean and land) and global high clouds. All products are well-documented, carefully validated and were externally reviewed prior to product release.

This presentation will highlight results from the currently available CDRs from CM SAF. A focus will be on uncertainty characterisation and results from validation as well as exemplary applications. Finally, the presentation will present an overview of the upcoming new editions of CDRs.

 
On the Space Weather Effect and CME-Driven Exospheres of the Moon and Ceres
Authors: Shi Hua-Shan , Chen Zheng-Xian , Ip Wing-Huen
Published: March 2020

A number of moon-sized objects in the solar system are characterized by the formation of a surface-bound exosphere. These include the Moon, Ceres, Jupiter’s icy moons, namely, Europa, Ganymede and Callisto, and several of the Saturnian icy moons including Rhea, Dione, and Tethys. There are several major source mechanisms ranging from micrometeoroid bombardment, photo-stimulated desorption, and energetic ion sputtering - in addition to the surface (or subsurface) thermal sublimation in the case of Ceres and the icy Moon. It is interesting that Ceres and the Moon could experience extreme space weather effects when they encounter large solar flare events or coronal mass ejection events. An important consequence is the production of a transient exosphere due to the sudden increase of ion sputtering rates. We have developed time-dependent Monte Carlo models that can be applied to the Moon and Ceres. Some simulation results will be described in this presentation with a view to construct the CME-driven H2O and O2 exosphere of Ceres and the flare-up of the lunar sodium corona and tail emission.
GPS Imaging of Mantle Driven Uplift of the Apennines, Italy
Authors: D'Agostino Nicola , Hammond William C.
Published: March 2020

One way for the continental lithosphere to extend is to increase its regional elevation, yet the mechanism for the formation of high-topography in actively extending continental settings (e.g., Tibet, Basin and Range, southwestern Balkans, Apennines) is still uncertain. It has been suggested that active extension in the Apennines Mountain chain in Italy is intimately related with regional topographic elevation. We use a newly updated GPS dataset and the GPS Imaging technique to show that the dynamic relief of the Apennines is currently increasing along its entire length by ~1 mm/yr. We image positive uplift along the entire length of the Apennine crest including the northern Apennines, Calabria and northern Sicily. The maximum rate is geographically aligned with the highest elevations and the topographic drainage divide. Relief is increasing in a ~120 km wide zone with a profile similar to the long wavelength topography, but not similar to the shorter wavelength topography generated by active faulting and erosion. A zone of minor active uplift is aligned with areas having restive volcanic fields and high geothermal potential west of the Apennines: e.g., Campi Flegrei, Alban Hills, and Lago Bolsena. However, the primary uplift axis aligns with the topography and zone of extension accommodating east-northeast translation of the Adriatic microplate relative to the Tyrrhenian Basin. Broad uplift occurs despite that the expected consequence of extension is crustal thinning and subsidence.   Anomalies in free-air gravity and deep seismic wavespeed suggest that elevation gain is driven by forces originating in the mantle. We use these results to address the hypothesis that these forces result from upward flow of asthenospheric mantle beneath the Apennines, possibly related to a sinking and detached slab previously attached to the Adriatic microplate, or from extensional flank flexure across the axis of the Apennine rift.
Cenozoic salt remobilization at the Baltic Sea sector of the northeastern North German Basin margin
Authors: Ahlrichs Niklas , Seidel Elisabeth , Noack Vera , Huster Hendrik , Hübscher Christian
Published: March 2020

In the scope of the “StrucFlow” project, we study salt tectonics at the salt-floored northeastern North German Basin margin, which is part of the Central European Basin System. Salt pillows are located in the Bays of Kiel and Mecklenburg, in the SW Baltic Sea, east of the Glückstadt Graben and west of the Tornquist-Teisseyre Zone. Salt pillow growth initiated in the Late Triassic and rejuvenated in Late Cretaceous to Tertiary times. We combine offshore and nearby onshore wells, shallow seismic surveys and high-resolution seismic sections from the BalTec data to derive a detailed seismo-stratigraphic correlation of Cenozoic units. This allows a more precise analysis of Cenozoic salt movement in the transition zone between the Glückstadt Graben and Tornquist Zone. We present key profiles and time-isochore maps revealing new insights into salt pillow evolution at the northeastern North German Basin margin and discuss active phases of salt movement in the context of the regional tectonic framework.

We associate the Late Cretaceous phase of salt pillow growth with far-field effects of the Africa-Iberia-Europe convergence and the consequent Pyrenean orogeny. The resulting change from extensional to compressional intraplate stress caused graben inversion and thrust faulting in northern Europe. However, Early Cenozoic successions reveal no indications for ongoing salt movement and suggest a phase of salt tectonic quiescence. Within the Eocene, salt was remobilized at the Baltic Sea sector of the North German Basin, leading to renewed salt pillow growth and erosion above pillow crests. We propose that this phase of salt remobilization is controlled by the coeval initiation of the European Cenozoic Rift System, between the rising Alps in the south and the opening North Atlantic Ocean in the northwest. Faulting within Quaternary deposits above a salt wall in the Bay of Kiel could indicate continuous salt movement and was possibly amplified by glacial isostatic adjustment.
Land ice distribution suggests an irregular pattern of interglacials across most of the Quaternary
Authors: Köhler Peter , van de Wal Roderik
Published: March 2020

From the combination of orbital theory with benthic δ18O it has been suggested which obliquity cycles led to interglacials during the Quaternary (e.g. Tzedakis et al., 2017). Here, we define interglacials, as deduced for the last 800 kyr (Past Interglacials Working Group of PAGES, 2016), by the absence of substantial northern hemispheric land ice outside of Greenland. When applied to land-ice distribution derived from a 3D-ice-sheet model-based deconvolution of the LR04-benthic δ18O stack into its temperature and sea-level components (de Boer et al., 2014) we find an irregular pattern of interglacials not only, as suggested so far, in the late Pleistocene but across most of the last 2.6 Myr. In the early Pleistocene eight obliquity cycles miss the onset of new interglacials, therefore increasing the average interglacial periodicity to 60 kyr. Both prolonged glacials (due to skipped terminations) and prolonged interglacials (so-called continued interglacials) are the reasons for these new irregularities. This finding adds new irregularities to the already known glacial/interglacial pattern during the last 1 Myr that include eleven obliquity cycles without new interglacials. Only in the Mid-Pleistocene in-between interglacials reappear regularly once in each obliquity cycle (every 41 kyr) with an exception around 1.1 Myr BP in which the onset of two successing interglacials is more than 100 kyr apart. This finding suggests that the notation of the Quaternary as an obliquity driven period with a growing influence of ice volume on the timing of deglaciations is too simple, or that our definition of interglacials, that seems to be suitable for the last 1.6 Myr, is not applicable to the whole Quaternary.

References:

de Boer, B., Lourens, L. J. & van de Wal, R. S. Persistent 400,000-year variability of Antarctic ice volume and the carbon cycle is revealed throughout the Plio-Pleistocene. Nature Communications 5, 2999 (2014). doi: 10.1038/ncomms3999.

Past Interglacials Working Group of PAGES. Interglacials of the last 800,000 years. Reviews of Geophysics 54, 162–219 (2016). doi: 10.1002/2015RG000482.

Tzedakis, P. C., Crucifix, M., Mitsui, T. & Wolff, E. W. A simple rule to determine which insolation cycles lead to interglacials. Nature 542, 427–432 (2017). doi: 10.1038/nature21364.