bluuebunny/crossref_metadata_2025 huggingface dataset:
Mapping global agricultural economic water scarcity to identify target areas for sustainable irrigation expansion
Authors: Rosa Lorenzo , Chiarelli Davide Danilo , Rulli Maria Cristina , Dell'Angelo Jampel , D'Odorico Paolo
Published: March 2020

With continuing growth in food demand and limited potential for cropland expansion, sustainable irrigation becomes an increasingly important strategy to ensure a reliable and resilient global supply of food in a changing climate. We here define and introduce the original concept of ‘agricultural economic water scarcity’ as the condition whereby croplands exposed to green water scarcity are not irrigated even though a sufficient amount of renewable blue water resources for irrigation is locally available. These conditions occur for instance as a result of a variety of socio-economic and political factors that impede irrigation. To date, little attention has been given to the analysis of this phenomenon and its role in the global geography of water scarcity. Here, we develop and apply a monthly agro-hydrological model to quantify and map croplands affected by agricultural green, blue, and economic water scarcity. By doing so we firstly provide a comprehensive, spatially explicit, global mapping of agricultural economic water scarcity across the global croplands. We then assess the water and food security implications of increased food production from irrigation expansion over economically water scarce croplands. Our results show that up to 25% of global croplands face agricultural economic water scarcity. Two thirds of economically water scarce lands are located in Sub-Saharan Africa, Eastern Europe, and Central Asia. Here, a sustainable irrigation expansion could increase food production and feed an additional 850 million people, while preventing further aggravation of blue water scarcity. The application of the concept of agricultural economic water scarcity has the potential to identify target areas for sustainable water and food security policies at global, regional, national, and local scales.
A weaker Atlantic Meridional Overturning Circulation at the Last Glacial Maximum led to a greater deep ocean carbon content
Authors: Menviel Laurie , Spence Paul , Skinner Luke , Tachikawa Kazuyo , Friedrich Tobias , Missiaen Lise , Yu Jimin
Published: March 2020

While paleoproxy records and modelling studies consistently suggest that North Atlantic  Deep Water (NADW) was shallower at the Last Glacial Maximum (LGM) than during pre-industrial times, its strength is still subject to debate partly due to different signals across the North Atlantic. Here, using a series of LGM experiments performed with a carbon isotopes enabled Earth system model, we show that proxy records are consistent with a shallower and weaker NADW. A significant equatorward advance of sea-ice over the Labrador Sea and the Nordic Seas shifts the NADW convection sites to the south of the Norwegian Sea. While the deep western boundary current in the Northwest Atlantic weakens with NADW, a change in density gradients strengthens the deep southward flow in the Northeast Atlantic. A shoaling and weakening of NADW further allow penetration of Antarctic Bottom Water in the North Atlantic despite its transport being reduced. This resultant globally weaker oceanic circulation leads to an increase in deep ocean carbon of ~500 GtC, thus significantly contributing to the lower LGM atmospheric CO2 concentration.

 
Swiping/pulse portable nozzle rainfall simulator
Authors: Neumann Martin , Kavka Petr , Laburda Tomáš , Tejkl Adam
Published: March 2020

Research of surface runoff, retention and infiltration processes consequenced with soil erosion by water is worldwide problem. There are numerous of natural and artificial research methods to study this phenomena. Use of rainfall simulators is one of the most popular artificial method. There are many types of rainfall simulators, we are introducing new type of portable nozzle-type rainfall simulator. This device combines advantages of pulse and swiping nozzle droplet generation. Device criteria were: (i) 2 person operation (ii) low water consumption (iii) wide range of rainfall intensity and kinetic energy. The simulator is supported by 4 metal legs. One fast-replaceable nozzle is placed above the center of a plot in 2 or 2,5 m height. Nozzle is connected to a control unit with stepper motor which allows it to swing, or stay in the vertical position with water flow interruption (solenoid valve). Required rainfall intensity is controlled by the velocity of stepper motor and water flow interruption periods. Metal collector is placed under the nozzle to drain the surplus water back to the reservoir. Standalone electric water pump is used to pump water into the system. 12 V DC and 230 V AC electricity supply is needed to run the device. Experimental plot can be up to 4 m2 (2x2 m square) in size but usually a 1 m2 (1x1 m) is used. Rainfall intensity could be used up to 100 mm h-1. Kinetic energy for the tested nozzles were 4 – 5,5 J m-2 mm-1. The first testing shows Christiansen Uniformity up to 93% for 1 m2 plot and 73% for 4 m2 plot. The research has been carried out within the framework of projects QK1910029, TJ02000234 and TH02030428.[M3] 
Spatiotemporal trends in flood hazards using MODIS time-series images in the Pearl River Basin (China)
Authors: Junliang Qiu , Xiankun Yang , Tarolli Paolo
Published: March 2020

The Pearl River Basin (PRB), as one of the most prosperous and densely populated areas in China, is a flood-prone area in which huge casualties and big economic losses constantly happen. Therefore, it is of great importance for the study on the characteristics of flood hazards and spatiotemporal trends in the PRB. Based on Google Earth Engine, this study combined 913-phase Modis 8-Day composite (MOD09Q1.006) images with 30-meters SRTM DEM to monitor flood dynamics in the PRB from 2000 to 2019 using an integrated threshold method. The approach synthesized several key factors, including spectrum characters of water body, cloud and the slope (slope<1º) information derived from SRTM DEM. Moreover, Sentinel-1 images were used to validate the accuracy of flood inundation maps. The results indicated that, from 2000 to 2019, the flood inundation area in PRB expanded significantly, especially in the Pearl River Delta region. With the development of urbanization, the expansion of impervious surfaces would probably increase the probability of flood hazard.
Assessments of IMERG precipitation over Europe
Authors: Navarro Andrés , García-Ortega Eduardo , Sánchez José Luis , Merino Andrés , Kummerow Christian , Tapiador Francisco J.
Published: March 2020

Accurate estimation of precipitation is essential in weather prediction, climate change research, and hydrologic applications. However, unlike temperature and pressure, precipitation fields can be spatially patchy and consequently extremely difficult to measure and predict. Many efforts have been made to measure precipitation since the 18th century, but building a global, consistent, and continuous database of rainfall is still challenging. The launch of the Global Precipitation Measurement Core Observatory (GPM-CO) in February 2019 emerged as a promising alternative to measure precipitation at global scale. After five years in orbit, the GPM Mission has produced enough quality-controlled data to allow a validation of their precipitation estimates over Europe.

This study evaluates Integrated Multi-Satellite Retrievals from GPM (IMERG) over Europe in order to evaluate application of the retrievals to hydrology. IMERG is compared with a pan-European precipitation dataset built on rain gauge stations, the ENSEMBLES OBServation (E-OBS) gridded dataset. Although there is overall agreement in the spatial distribution of mean precipitation (R2 =0.8), important discrepancies are revealed in mountainous regions, specifically the Pyrenees, the Alps, west coast of the British Isles, Scandinavia, the Italian and Iberian peninsulas, and the Adriatic coastline. The results show that the strongest contributors to poor performance are pixels where IMERG has no gauges available for adjustment. If rain gauges are available, IMERG yields results similar to those of the surface observations, although the performance varies by region. However, even accounting for gauge adjustment, IMERG systematically underestimates precipitation in the Alps and Scandinavian mountains. Conversely, IMERG overestimates precipitation in the British Isles, Adriatic coastline, Italian Peninsula, and eastern European plains. Additionally, the research shows that gauge adjustment worsens the spatial gradient of precipitation because of the coarse resolution of Global Precipitation Climatology Centre data (GPCC).
Tectonics from topography : insights from high-resolution hillslope morphology analysis
Authors: Godard Vincent , Hippolyte Jean-Claude , Cushing Edward , Espurt Nicolas , Fleury Jules , Bellier Olivier , Ollivier Vincent , Team Aster
Published: March 2020

The spatial distribution of tectonic uplift is often investigated using river profiles, as fluvial gradient is predicted to be strongly dependent on rock uplift. A similar response is expected from hillslope morphology which is also dependent on the relative base-level lowering rate. However, the reduced sensitivity of near-threshold hillslopes and the limited availability of high resolution topographic data has often been a major limitation for their use to investigate the distribution of tectonic activity.

Here we combined high-resolution analysis of hillslope morphology and cosmogenic nuclide-derived denudation rates to constrain the distribution of rock uplift across a thrust system at the Southwestern Alpine front in France. Our study is located in the Valensole Mio-Pliocene basin, where a series of folds and thrusts has deformed a plateau surface. Using a 1-m LiDAR Digital Terrain Model, we analyzed the morphology of hillslopes and extracted proxies for the relative spatial variations in denudation such as hilltop curvature (CHT) and non-dimensional erosion rates (E*). We observed systematic variation of these metrics coincident with the location of a major underlying thrust system identified by seismic surveys. Using a simple deformation model, the inversion of the E* pattern allows us to constrain the geometry of a blind thrust, which is consistent with available geological and geophysical data.

We also sampled clasts from eroding conglomerate at several hilltop locations for 10Be and 26Al concentration measurements. Calculated hilltop denudation rates range from 40 to 120 mm/ka. These denudation rates appear to be correlated with E* and CHT extracted from the morphological analysis, and are used to derive absolute estimates for the fault slip rate. This high resolution hillslope analysis allows us to resolve short wavelength variations in rock uplift that would not be possible to unravel using commonly used channel profile-based methods.
Spatiotemporal Change Analysis of of Water, Energy and Food Resources in Yellow River Basin
Authors: Ma Liming , Li Chaoqun , Hu Xiaoyan , Wang Peng , Li Xiao
Published: March 2020

The Yellow River Basin is rich in land, energy, and mineral resources, which is an important energy base and major food producing area in China. However, water shortages have become a key factor restricting the development of the basin. With the economic and social development and population growth, resources demand of water, food and energy in the river basin has been further increased under the drive of national energy security and food security strategies. The conflict between resource supply and demand has become more prominent. This paper selected 9 provinces of the Yellow River Basin as the study area, and collected 16-year time series data, and quantitatively describes the temporal and spatial coordinated changes of water, energy, and food through methods such as MK test and synergetic evaluation system. The results show that in the nine provinces of the Yellow River Basin, the water supply has increased slightly, and energy and food production have increased significantly. The spatial differences of water supply and food production have little change and are relatively stable, while the change of spatial differences in energy production are more obvious with a downward trend, indicating that regionalization of energy production areas is becoming more and more obvious. According to the synergetic evaluation system, the coefficients of synergy for all of the nine provinces are gradually increasing. The evaluation coefficient of Henan is relatively high, indicating that Henan has a positive synergy of water, energy, and food resources. And the Ningxia province has the lowest evaluation coefficient. According to the results, the water energy and food system reconfiguration should be carried out for key provinces, and the allocation of water energy and food resources should be optimized to maximize the utilization of the three resources and achieve sustainable use.First of all, adjusting the energy structure among the provinces with poor synergy. For example, raw coal is still the core resource of energy consumption which is water-intensive. Reduce the investment in coal chemical industry and other high water-consumed energy industry to have a better synergy coefficient. Also, develop more clean energy, for example, hydro-power, nuclear power and wind power. Nowadays, the environment-friendly and resource-saving clean energy portion is less than 10% of the total energy consumption. The waste resources can be reuse to provide green energy. Last, high-end production technology in energy production is important to guarantee the water and energy safety. 
Detecting microbial pigments from gypsum using Raman spectroscopy: from field prospection to laboratory studies
Authors: Jehlicka Jan , Němečková Kateřina , Culka Adam
Published: March 2020

Terrestrial detection of biomarkers in various mineral matrices using Raman spectrometers including field deploying of miniature instrumentation in Mars-analogue sites can be seen as a training for next Martian missions. In fact, both the European Space Agency (Exomars) and North American Space Agency (Mars 2020) robotic rovers will include Raman spectrometers. Feasibility of detecting biomarkers of extremophilic cyanobacteria and algae (pigments, osmotic solutes and lipids) using Raman microspectrometry was reviewed previously. Here the idea is to show - firstly how portable Raman instrumentation permits to detect carotenoids fast and onsite under field conditions. Secondly, laboratory microspectrometric investigations allow to obtain more detailed information about spatial distribution of pigments originating from microorganisms.

Macrocrystalline gypsum layers and aggregates are well-known from Tertiary series in Sicily and Eastern Poland. In Southern Sicily gypsum sediments accumulated during Messinian crisis (Late Miocene) are outcroping and were investigated near Scala dei Turchi, Torre Salsa and Siculiana Marina. Polish Tertiary (Badenian, Middle Miocene) examples of gypsum colonisations of decimetre long outcropping crystals were studied near Chotel Czerwony, Skorocice and Chwalowice. Miniature portable Raman spectrometers equipped with green lasers allowing recording of resonance Raman signals of carotenoids are evaluated here. Possibilities of collecting spectra of carotenoids under non-resonant conditions using a portable sequentially shifted Raman spectrometer (785 and 853nm lasers) are shown as well. Observed shifts of positions of Raman features of carotenoids between gypsum samples (and sites) are discussed and critically evaluated. In addition, acquired data are compared to data obtained through laboratory Raman microspectrometric investigations. Selected zones of microbial colonisations of few types of gypsum are described from the point of view of the presence of algae and cyanobacteria. Pigments are detected through conventional Raman microspectrometric measurements. Carotenoids were documented in major part of samples (common Raman bands at around 1525, 1157, and 1004 cm−1). Additionally, Raman spectra of other pigments were recorded in several zones using near infrared excitation (785 nm): chlorophyll (1151, 1327, 1287, 1184, 917, and 745 cm−1), scytonemin (1593, 1152, 1438, and 1173 cm−1) and phycobiliproteins (1633, 1584, 1371, 1236, 813, and 667 cm−1).

Portable instrumentation permits detection of carotenoids in gypsum fast and onsite under field conditions. Raman microspectrometric investigations of colonisations allow to gather detailed information about pigment distribution in micrometric zones of gypsum samples.
Characterization of human behavior in records of personal solar ultraviolet exposure records
Authors: du Preez David Jean , Blesic Suzana , Wright Caradee Y. , Stratimirovic Djordje , Ajtic Jelena , Allen Martin , Bencherif Hassan
Published: March 2020

We investigated scaling properties of measurements of personal exposure to solar ultraviolet radiation (pUVR) using the 2nd order detrended fluctuation analysis (DFA2) and the wavelet transform spectral analysis (WTS). Studies of pUVR are important to identify populations at-risk of excess and insufficient exposure given the negative and positive health impacts, respectively, of time spent in the sun. These very high frequency recordings are collected by electronic UVR dosimeters. We analyzed sun exposure patterns of school children in South Africa and construction workers and work site supervisors in New Zealand, and we found scaling behavior in all our data. The observed scaling changed from uncorrelated to long-range correlated with increasing duration of sun exposure. We found peaks in the WTS spectra that mark characteristic times in pUVR behavior, which may be connected to both human outside activity and natural (solar) daily cycles. We further hypothesized that the WT slope would be influenced by the duration of time that a person spends in continuum outside and addressed this hypothesis by using an experimental study approach. To that end we performed combined DFA2-WTS analysis on a subset of individual records taken on the same day under very similar outdoor conditions and used the theoretical superposition rule provided by systematic assessments of effects of trends and nonstationarities on DFA2 as a methodological mean to trace and subsequently model human behavioral patterns in pUVR time series.
Geohazard assessment of submarine salt-related thin-skinned faults: Levant Basin, offshore Israel
Authors: Laor May , Gvirtzman Zohar
Published: March 2020

The Israeli continental slope is dissected by numerous thin-skinned normal faults, deforming the Pliocene-Quaternary section. This extensional faulting is caused by subsurface deformation of the Messinian salt underlying Pliocene rocks. It began in the early Gelasian, at 2.6 Ma, and it is still active today, as indicated by the ruptured seabed. High-resolution bathymetric data reveal shore-parallel seabed steps reaching heights of a few tens of meters. Considering that since the beginning of faulting the average sedimentation rate (100-400 m/My) exceeds the displacement rate (50-100 m/My), the presence of numerous unburied fault scarps indicates seismic ruptures rather than slow creep. For example, considering recent sedimentation rates as measured in seabed cores (5 cm/ka = 50 m/My), if an earthquake produces a 5-m-high fault scarp, it would take about 100 ky to bury it. These preliminary considerations highlight the importance of hazard assessment for seabed infrastructures.

The recent development of gas fields offshore Israel, as well as the increasing number of planned infrastructures on the seafloor requires a risk assessment, geohazard management, and particularly accurate mapping of faults. Unlike onshore geohazard management, there is no statutory fault map for offshore Israel. Moreover, 'active' and 'potentially active' faults in the offshore area are still not defined. The purpose of this study is to prepare a fault map and discuss criteria for defining the level of fault activity in the marine environment. To accomplish this goal, we use high-resolution bathymetric data and 3D seismic surveys, allowing 3D mapping of faults much better than usually possible onshore.

For bathymetry, we developed an algorithm, which automatically calculates the height of fault scars along predefined segments. Results indicate higher faults scarps in the north, consistent with extension measurement and steepness of the continental slope that also increases northward. A 3D mapping of fault planes shows that (1) many small faults at the seabed are actually segments of a major fault. This allows reducing the total number of faults to a few large ones. (2) A significant fault can be hidden below the surface with no bathymetric expression. (3) The structure of a seismic reflector dated to 350 ka emphasizes areas with greater recent activity much better than the best available bathymetric data. This allows a quick way to focus on hazardous areas. The next stage of the research will be to measure the area of fault planes and calculate potential earthquake magnitudes. Altogether, we point out the advantage of 3D seismic mapping for geohazard assessment.
TeaTime4App – Raising awareness about the role of soils with the educational “Tea Bag Index App”
Authors: Miloczki Julia , Wawra Anna , Gansberger Markus , Hummer Philipp , Sandén Taru
Published: March 2020

With the Tea Bag Index (TBI) App, we aim to foster awareness of the importance of soils and their ecosystem services to students above the age of 10. The TBI app consists of three categories of hands-on activities: Basic soil attributes, Soil observations, and Tea Bag Index. Basic soil attributes include land use, soil colour and soil life, whereas soil observations go further to Texture by Feel, Spade Test and observation of soil pollution. The Tea Bag Index (Keuskamp et al., 2013) provides an easy and scientifically recognized way to measure decomposition rates and stabilisation of organic matter in soils. The method consists of burying tea bags and measuring the degradation of organic material after three months’ time. Each of the methods includes clear instructions and extra information in the app. Data gathered are interactively shown on a map in the App as well as online. Hence, students are encouraged to gain hands-on science experience and to witness how science connects across regions, countries and cultures. By using playful tools such as rewards, badges and a point system, we attract and maintain the interest of students. Social media channels are used to exchange and share their results as well as to reach teachers and citizen scientists in order to inspire them to use the educational App.

Having this awareness on soil and its functions, citizen scientists can make valuable contributions to the sustainable use of soils. They also have the opportunity to participate in a global scientific initiative, acquire skills in conducting a scientific experiment and gain knowledge on soil functions. The science community, on the other hand, increases its understanding of factors influencing decomposition (and associated soil functions) at different times and in different places globally.

Moreover, the TBI App can be used for „Content Language Integrated Lessons“ (CLIL), which is the use of a foreign language for the integrative teaching of content and language competence outside of language teaching in agricultural schools in Austria. Individual learning outcomes (ILOs) of an agricultural school class testing the TBI App were evaluated in an online questionnaire. Results showed high appreciation of activities offered by the TBI App and high motivation of students to contribute to science.

 

 

Keuskamp, J.A., Dingemans, B.J.J., Lehtinen, T., Sarneel, J.M. and Hefting, M.M. (2013), Tea Bag Index: a novel approach to collect uniform decomposition data across ecosystems. Methods Ecol Evol, 4: 1070-1075. doi:10.1111/2041-210X.12097
NASA and GFZ GRACE Follow-On Mission: Status, Science, Advances
Authors: Flechtner Frank , Landerer Felix , Save Himanshu , Dahle Christoph , Bettadbur Srinivas , Watkins Mike , Webb Frank
Published: March 2020

The twin satellites of the Gravity Recovery and Climate Experiment (GRACE) Follow-On mission were successfully launched in May-2018. The primary objective of the mission is to continue the 15-year GRACE (2002-2017) global data record of Earth’s monthly mass changes. These measurements have become an indispensable tool to quantify and track Earth’s water movement and surface mass changes across the planet. Monitoring changes in ice sheets and glaciers, near-surface and underground water storage, the amount of water in large lakes and rivers, as well as changes in sea level and ocean currents provides an integrated global view of how Earth’s water cycle and energy balance are evolving.

In this presentation we will present the current mission status, including instrument and flight system performance, discuss science data quality and performance as well as recent science results from the first two years of observations, and address data continuity from GRACE to GRACE Follow-On.
Change in water discharge and sediment load on the Loess Plateau, China
Authors: Zheng Haiyan , Miao Chiyuan
Published: March 2020

Over the past 50 years, a series of soil and water conservation measures have been implemented on the Loess Plateau, including biological, engineering, and agricultural measures. As a result, water discharge and sediment load on the plateau have undergone significant changes. In this study, we compared the water discharge and sediment load at more than 100 hydrological stations across the Loess Plateau during the period 2008–2016 (P2) with the water discharge and sediment load during the period 1971–1987 (P1), and detected the main sources of sediment in each of the two periods. We then performed an attribution analysis to quantify the influence of different factors on the changes in sediment load. We found the following results: (1) Water discharge was reduced by 22% in P2 compared with P1, whereas the sediment load was reduced by 74%. (2) Sediment resources are mainly concentrated between Toudaoguai and Tongguan stations: this region contributed more than 88% of the total sediment load at the terminal station (Huayuankou station) in both P1 and P2. (3) When considering only the changes in sediment concentration on the Loess Plateau, we conclude that the contribution of human activities was greater than 72%. This study provides a detailed description of the temporal and spatial variations in water and sediment across the Loess Plateau, providing a reliable reference for the future development of ecological soil and water conservation measures on the Loess Plateau.
Global Land Surface Temperature from historical NOAA AVHRR datasets (1981-2000)
Authors: Ma Jin , Zhou Ji , Göttsche Frank-Michael , Wang Shaofei
Published: March 2020

As one of the most important indicators in the energy exchange between land and atmosphere, Land Surface Temperature (LST) plays an important role in the research of climate change and various land surface processes. In contrast to in-situ measurements, satellite remote sensing provides a practical approach to measure global and local land surface parameters. Although passive microwave remote sensing offers all-weather observation capability, retrieving LST from thermal infra-red data is still the most common approach. To date, a variety of global LST products have been published by the scientific community, e.g. MODIS and (A)ASTR /SLSTR LST products, and used in a broad range of research fields. Several global and regional satellite retrieved LSTs are available since 1995. However, the temporal-spatial resolution before 2000 is generally considerably lower than that after 2000. According to the latest IPCC report, 1983 – 2012 are the warmest 30 years for nearly 1400 years. Therefore, for global climate change research, it is meaningful to extend the time series of global LST products with a relatively higher temporal-spatial resolution to before 2000, e.g. that of NOAA AVHRR. In this study, global daily NOAA AVHRR LST products with 5-km spatial resolution were generated for 1981-2000. The LST was retrieved using an ensemble of RF-SWAs (Random Forest and Split-Window Algorithm). For a maximum uncertainty in emissivity and water vapor content of 0.04 and 1.0 g/cm2, respectively, the training and testing with simulated datasets showed a retrieval accuracy with MBE of less than 0.1 K and STD of 1.1 K. The generated RF-SWA LST product was also evaluated against in-situ measurements: for water sites of the National Data Buoy Center (NDBC) between 1981 and 2000, it showed an accuracy similar to that for the simulated data, with a small MBE of less than 0.1 K and a STD between 0.79 K and 1.02 K. For SURFRAD data collected between 1995 and 2000, the MBE is -0.03 K with a range of -1.20 K – 0.54 K and a STD with a mean of 2.55 K and a range of 2.08 K – 3.0 K (site dependent). As a new global historical dataset, the RF-SWA LST product can help to close the gap in long-term LST data available to climate research. Furthermore, the data can be used as input to land surface process models, e.g. the Community Land Model (CLM). In support of the scientific research community, the RF-SWA LST product will be freely available at the National Earth System Science Data Center of China (http://www.geodata.cn/).
Paleo-surface ruptures at both sides of a pressure ridge along Alhama de Murcia Fault (SE Spain)
Authors: Gómez-Novell Octavi , Ortuño María , García-Mayordomo Julián , Masana Eulàlia , Rockwell Thomas , Baize Stéphane , Pallàs Raimon
Published: March 2020

The Alhama de Murcia Fault (AMF) is one of the most seismically active faults in the Iberian Peninsula, with important associated historical and instrumental seismicity (e.g. the 1674 IEMS VIII and 2011 Mw 5.1 Lorca earthquakes), and numerous geomorphic and paleoseismic evidence of paleoearthquakes. It is an oblique left-lateral strike slip fault within the Eastern Betics Shear Zone (EBSZ), a nearly 500 km long fault system that absorbs a great part of convergence between the Nubian and Eurasian plates. Previous paleoseismic studies have mainly focused on the southwestern and especially the central segment of the fault and yielded slip rate values ranging from 1.0 up to 1.7 mm/yr. In the central segment (Lorca-Totana), the fault splays into several branches, the two frontal ones forming a pressure ridge. Paleoseismic trenches have exclusively been dug in the northwestern fault of the pressure ridge, where most of the displacement is along strike, while the expected reverse southeastern branch has never been directly observed.

We present the first results of paleoseismic trenching across a complete transect of the pressure ridge in the Lorca-Totana segment of AMF. To do so we excavated an exceptionally large trench (7 m deep) in the NW branch and 5 trenches in the SE branch. We have been able to: a) extend the paleoearthquake catalogue in the NW branch by interpreting a total of 13 paleoearthquakes, 6 of which were not identified in previous studies. A restoration analysis has been performed; b) unveil the existence and recent activity (Holocene) of the thrust that bounds the pressure ridge to the SE. We have interpreted at least 5 surface ruptures, with the last one being younger than 8-9 kyr BP, based on new radiocarbon dates.

The study of these two sites allows for the refinement of the seismic parameters of the fault, formerly inferred from the study of a single branch. In this sense, the more complete paleoearthquake catalogue will allow for reassessment of the recurrence intervals assigned to the fault and new slip rate estimates will be inferred by combining data from the two studied sites. Furthermore, forthcoming OSL dates may allow us to prove or reject the synchronicity of surface ruptures on both sides of the pressure ridge, shedding light on the rupturing style of this fault system during the Late Quaternary. We discuss how these new data on fault-interaction may affect several seismic parameters and their repercussion in source modelling for fault-based probabilistic seismic hazard assessments (PSHA) of the region.
Kerguelen Plateau Drift Deposits: outstanding high-resolution chronicle of Cenozoic climatic and oceanographic changes in the southern Indian Ocean
Authors: Westerhold Thomas , Uenzelmann-Neben Gabriele
Published: March 2020

Kerguelen Plateau (KP), one of the world’s largest Large Igneous Provinces, is located in a key region in the southern Indian Ocean. Its complex topography has a strong influence on pathways of water masses within the Antarctic Circumpolar Current (ACC) and the Antarctic Bottom Water (AABW). Thick sediment packages deposited on top and around KP are a high-fidelity recorders of significant modifications in pathways and intensities of water masses flowing across the KP during the Cenozoic. Already the previously ODP spot cored sedimentary sequences demonstrated their outstanding potential as a far-field monitor for the evolution of the Antarctic Ice Sheet, for the climate variability in the Warmhouse World of the middle to late Eocene, for changes in ocean circulation, and for migration of the Polar Frontal System. Here we propose to revisited KP and recover a complete, multiple-hole drilled, carbonate rich sedimentary successions from Labuan and Ragatt Basin area by an IODP Expedition. Only high-quality drilled, undisturbed new material will allow studying the interaction of climatic and tectonic changes of the last 66 million years and provide important information on the formation and dynamics of the Antarctic ice sheet due to the unique location of the KP.
A gridded inventory for global CFC-11 emissions from 2008 to 2019
Authors: Sheng Jianxiong , Prinn Ronald
Published: March 2020

CFC-11 is a potent ozone depleting gas and is regulated under the Montreal Protocol. The rate of decline in global CFC-11 concentrations has slowed since 2013 largely due to the renewed, increasing emissions from eastern China (Montzka et al, Nature, 2018; Rigby et al, Nature, 2019). However, regional inversions suggest that this increase only accounts for 40-60% of the global rise. Therefore, there is an urgent need for emission estimates in other regions or countries. A global 3D inversion of atmospheric measurements is essential to improve our understanding of CFC-11 emission trends and sources, but it requires a reliable emission inventory as a prior estimate. In this study, we develop a gridded bottom-up inventory of global CFC-11 emissions from 2008 to 2019. Our inventory is driven by various, gridded proxy datasets including population, energy consumption, GDP per capita, and industrial clusters. A machine learning model is built between the proxy data and the previous emission estimates for eastern China, Korea, and Japan derived from inversions of AGAGE and NOAA surface measurements (Rigby et al, Nature, 2019). Our model is cross-validated in the East Asia and then applied to the other regions and countries to construct the gridded inventory with error characterization. Use of our inventory as prior information in future inverse analyses can help better quantify spatial distributions and sources of CFC-11 emissions as well as better guide the regulation of CFC-11.
The location of Component Reconnection at the Earth’s Magnetopause During Dominant IMF By and Large Dipole Tilt Conditions
Authors: Trattner Karlheinz , Fuselier Stephen , Petrinec Steven , Burch James , Cassak Paul , Ergun Robert , Giles Barbara , Torbert Roy
Published: March 2020

The interplanetary magnetic field (IMF) convected with the solar wind drapes around the region of space dominated by Earth’s geomagnetic field and undergoes a process called magnetic reconnection at the magnetopause; the boundary layer that separates these two distinct regimes. Magnetic reconnection changes the topology of magnetic field lines and is known to convert magnetic energy into kinetic energy and heat. This fundamental process occurs in many environments, spanning from laboratory plasmas to the heliosphere, the solar atmosphere, and to astrophysical phenomena. Magnetic reconnection at the Earth’s magnetopause has been observed at various times and places as either anti-parallel and/or component reconnection. A model known as the Maximum Magnetic Shear Model combines these two scenarios, creating long reconnection lines crossing the dayside magnetopause along a ridge of maximum magnetic shear. 
The connection points between the anti-parallel and the component reconnection segments of the reconnection line are known as ‘Knee’ regions. Using observations from the MMS satellites, it was shown that the location of the Knee region depends strongly on the local draping conditions of the IMF across the magnetopause, with certain draping conditions causing a deflection of the location along the anti-parallel reconnection region. This study discusses an event that shows that the entire component reconnection X-line crossing the dayside magnetopause can be affected by this deflection. This result emphasizes the importance of anti-parallel reconnection that seems to control where component reconnection is occurring. 
An n-alkane-based Holocene climate reconstruction in the Altai Mountains, northern Xinjiang, China
Authors: Ran Min
Published: March 2020

The climate in the Altai Mountains is highly sensitive to large-scale forcing factors because of its special geographic location. Based on n-alkane data of 150 samples and with a chronologic support of 15 accelerator mass spectrometry (AMS) dates from a 600-cm core at GHZ Peat, the Holocene climatic changes in the Altai Mountains were reconstructed. The reconstruction revealed a warming and drying early Holocene (~10,750-~8500 cal. yr BP), a cooling and persistent dry middle Holocene (~8500-~4500 cal. yr BP), and a cooling and wetting late Holocene (~4500-~700 cal. yr BP). The Holocene temperature changes were primarily controlled by the summer solar radiation with a certain time lag in the early Holocene and also modulated by solar activity, and the time lag in the early Holocene was probably resulted from ice and permafrost melting. The Holocene moisture in the southern Altai Mountains was likely modulated by the North Atlantic Oscillations (NAO) or by the Atlantic Multi-centennial Oscillations (i.e., AMO-like) or by temperature, and or by any combination of the three (NAO, AMO-like, and temperature).
A teleconnection pattern of 10-30-day atmospheric oscilations over North Pacific during summer: Chracteristics and maintainance mechanism
Authors: Du Lei , Lu Riyu
Published: March 2020

The present study investigates the intraseasonal variations of meridional winds over North Pacific during summer based on reanalysis datasets. It is shown that the band of 10-30 days is the main component of total intraseasonal varaitions. We identified a teleconnection pattern over North Pacific at this band . This teleconnection pattern is characterized by a zonally-oriented wave-like structure with a zonal wavenumber 5, and does not show a phase-locking feature. In addition, the anomalies associated with the teleconnection pattern exhibit a roughly baratropic structure. Further analyses suggest that the teleconnection pattern can gain energy from the basic flow through the baroclinic energy conversion, while the barotropic energy conversion plays a trivial role.
Two Cases Studies of Cloud Structures of Aircraft Icing Tests in the Northwest of China
Authors: Sun Jing
Published: March 2020

Two tests of aircraft icing observations were conducted on March 2018 in Xin Jiang in northwest of China. The icing conditions are studied using observations of satellite, radar, soundings and simulations using the WRF mesoscale model coupled with CAMS cloud scheme. The large-scale weather systems of the two icing cases are the vortex and the shallow trough on 500hPa separately, accompanied by the cold front on the surface. The icing time is in the early stage of vortex system and the middle stage of shallow trough system. The icing clouds are both low and middle clouds. The cloud top height is 4km and the cloud top temperature is -15~-25℃. The cloud bottom height is 1.5km and the cloud thickness is 1-3km. The optical thickness is larger than 12 and the radar reflectivity is less than 10dBZ. There is an inversion layer of the shallow trough. The microphysical structures of CPEFS model simulations show that the icing cloud is composed of large number of supercooled water and few ice particles. The CIP initial icing potential results can basically reflect the icing height and time of the two cases.
Tectonic and geomorphic controls on the distribution of submarine landslides across active and passive margins, eastern New Zealand
Authors: Watson Sally , Mountjoy Joshu , Crutchley Gareth
Published: March 2020

Submarine landslides occur on continental margins globally and can have devastating consequences for marine habitats, offshore infrastructure and coastal communities due to potential tsunamigenic consequences. Evaluation of the magnitude and distribution of submarine landslides is central to marine and coastal hazard planning. Despite this, there are few studies that comprehensively quantify the occurrence of submarine landslides on a margin-wide scale.

 

We present the first margin-wide submarine landslide database along the eastern margin of New Zealand comprising >2200 landslide scars and associated mass-transport deposits. Analysis of submarine landslide distribution reveals 1) locations prone to mass-failure, 2) spatial patterns of landslide scale and occurrence, and 3) the potential preconditioning factors and triggers of mass wasting across different geologic settings.

 

Submarine landslides are widespread on the eastern margin of New Zealand, occurring in water depths from ~300 m to ~4,000 m. Landslide scars and mass transport deposits are more prevalent, and on average larger, on the active margin, compared the passive margin. We attribute higher concentrations of landslides on the active margin to the prevalence of deforming thrust ridges, related to active margin processes including oversteepening, faulting and seamount subduction. Higher sediment supply on the northernmost active margin is also likely to be a key preconditioning factor resulting in the concentration of large landslides in this region.

 

In general, submarine landslide scars are concentrated around canyon systems and close to canyon thalwegs. This suggests that not only does mass wasting play a major role in canyon evolution, but also that slope undercutting in canyons may be a fundamental preconditioning factor for slope failure.

 

Results of this study offer unique insights into the spatial distribution, magnitude and morphology of submarine landslides across different geologic settings, providing a better understanding of the causative factors for mass wasting in New Zealand and around the world.

 
Geochronology and Lu-Hf isotopic study of the granodioritic pulse in the Qaradagh batholith (NW Iran)
Authors: Simmonds Vartan , Moazzen Mohssen , Topuz Gültekin , Mohammadi Ali
Published: March 2020

The Qaradagh batholith in northwest Iran mainly comprises granodioritic rocks, which makes more than 50% of the batholith. This lithology is the first intrusive pulse within this batholith and the oldest Tertiary magmatism in the region, though other younger pulses of granite, diorite, quartz-diorite, syenite, quartz-syenite, monzonite, quartz-monzonite, quartz monzodiorite, monzogranite and gabbro intruded the main body. These magmatic rocks have intruded the Upper Cretaceous and Paleogene sedimentary, volcano-sedimentary and igneous rocks.

The Qaradagh batholith hosts vein-type and some local stock-work type Cu–Au–Mo mineralization, especially in its central parts, while skarn-type deposits have been formed at its contacts with peripheral carbonate rocks. Its extension towards the north into the neighboring south Armenia (which is part of the South Armenian Block) is known as the Meghri–Ordubad pluton (MOP), which hosts several large porphyry Cu–Mo deposits and other precious and base metal mineralizations. U–Pb geochronology on the zircons separated from the granodioritic unit yielded a weighted 206Pb/238U mean age of 43.81 ± 0.18 (MSWD=1.38) and a Pb*/U concordia age of 44.04 ± 1.00 Ma (MSWD= 24), which correspond to Middle Eocene.

Since the Qaradagh batholith and especially its earliest magmatic phase are considered as the oldest plutonic event of the Cenozoic age in northwest Iran, thus this investigation testifies to the fact that intrusive activities of Tertiary in this region has commenced in Middle Eocene, contrary to the opinion of the majority of authors who believe that plutonism in this region occurred during Oligocene.

However, this age is much older than the molybdenite Re–Os ages of quartz-sulfide veins hosted by granodioritic rocks (25.19 ± 0.19 to 31.22 ± 0.28 Ma), indicating that mineralization in this batholith is related to another much younger intrusive phase, and even to several phases, as the published ages of molybdenites from various veins and mineralized zones show a large interval. Comparing the obtained age with those from the MOP in southern Armenia indicate that southern part of the MOP is almost coeval with the emplacement of the granodioritic rocks in Qaradagh batholith.

The U and Th contents of the zircons range from 17.1 to 1534.0 and from 4.9 to 641.0 ppm, respectively, with Th/U ratios between 0.66 and 5.82 (mean of 1.26), indicating a magmatic source. Meanwhile, the εHf(t) values of the zircons range from 8.7 to 11.1 with the mean of 9.5, which are plotted between the CHUR and the Depleted Mantle evolution lines, indicating a juvenile and homogeneous magmatic source and the predominance of mantle-derived magmas with limited crustal assimilation.
High-resolution Simulations of a Hot-and-polluted Event with Detailed Local Climate Zone Information over the Greater Bay Area in South China
Authors: Chen Junwen , Tam Chi-Yung , Yim Steve H.L. , Cai Meng , Wang Ran , Li Xinwei , Ren Chao , Zhang Tuantuan , Gao Peng
Published: March 2020

A new 10-type urban Local Climate Zone (LCZ) classification with 100-m resolution was developed, following the guidelines of the World Urban Database and Access Portal Tools (WUDAPT) over the Greater Bay Area (GBA). This LCZ dataset was incorporated into the Building Environment Parameterization (BEP)-Building Energy Model (BEM) multi-layer urban canopy scheme used by the Weather Research and Forecasting (WRF) model, with key parameters (such as fraction of impervious surface, building height/width, road width, air conditioning usage) determined from local building morphology and energy consumption patterns. The impacts of using such detailed 10-type LCZ, as compared to using remapped 3-type LCZ and using default WRF 1-type urban land cover were assessed, based on parallel integrations of the WRF system at 1-km resolution for a historical hot-and-polluted event over the GBA. It was found that the model surface temperature, air temperature, humidity and wind speed in the 10-type LCZ run were in closer agreement with in-situ observations, demonstrating the value of detailed urban LCZ data in improving the model performance. Smaller diurnal temperature range and higher nighttime temperature were found in the 10-type LCZ run compared to the 3-type LCZ and 1-type runs. Increased building height in the 10-type LCZ setting also reduces positive bias of wind speed in the lower planetary boundary layer at urban locations. The cold and dry biases over the non-urban areas in the 10-type LCZ run could be further reduced through considering updated land cover, soil type, soil hydraulic/thermal parameters, soil moisture/temperature. Owing to the improvement in capturing the urban meteorology, incorporating more detailed LCZ classification might also improve air-quality simulations. These findings should be relevant to the development of comprehensive, high-resolution earth system models, which are an indispensable tool for mitigation of and adaption to regional environmental and climate changes.