bluuebunny/crossref_metadata_2025 huggingface dataset:
Digital soil mapping of organic carbon and it’s spatial distribution uncertainty in field scale
Authors: Guo Yan , Liu Ting , Shi Zhou , Wang Laigang
Published: March 2020

     Soil organic carbon (SOC) is a key property that affects soil quality and the assessment of soil resources. However, the spatial distribution of SOC is very heterogeneous and existing soil maps have considerable uncertainty. Traditional polygon-based soil maps are less useful for fine-resolution soil maps modeling and monitoring because they do not adequately characterize and quantify the spatial variation of continuous soil properties. And recently, digital soil mapping of organic carbon is the main source of information to be used in natural resource assessment and soil management. In this study, we collected 100 soil samples on a 50 m grid to conduct soil maps of topsoil (0-20 cm) organic carbon in a 500×500m field and evaluate the uncertainty by spatial stochastic simulation. The map of soil organic carbon generated by inverse distance weighting interpolation indicated that the average topsoil SOC is 11.59±0.61g/kg with averaged standard deviation error is 0.61. In order to evaluate the uncertainties, numbers were defined as 50, 100, 200, 500, 1000, 5000, 10000 with interval of 2×2 m to conduct conditional simulation. The standard deviation error gradually declined from 0.74 to 0.51 g/kg. Then, the uncertainty of SOC was expressed as the range of the 95% confidence intervals of the standard deviation error. Maps of uncertainty showed fine spatial heterogeneity even the numbers of simulations reached 10000. Compared with inverse distance weighting interpolation method, conditional simulation approach can improve the fine-resolution SOC maps. For some points, the simulated values deviated from the averaged values while closed to the observed values. On the whole, the maps of uncertainty showed larger waves in the field-edge and different SOC contour border. Consideration of the sample distribution and sampling strategy, the uncertainty map provides a guide for decision-making in additional sampling.

Key words: Soil organic carbon (SOC); uncertainty assessment; conditional simulation; digital soil mapping

Acknowledgements

This material is based upon work funded by National Natural Science Foundation of China (No. 41601213), Major science and technology projects of Henan (171100110600), the Key Science and Technology Program of Henan (182102410024).
Geovisualization prevention warning information service for maritime disaster
Authors: Fan Yang-Ming , Doong Dong-Jiing , Hsueh Ping-Chang
Published: March 2020

The target of this study is diversified development and uploading and sharing of prevention warning (or inquiry) information in real time, and geovisual display the information after analyzing the observations and predictions, making it easier for the government and the public to browse the latest various marine meteorological information. Terrible marine environment such as large tidal difference, swell, typhoon huge waves, and storm surge, etc. could easily cause severe maritime disasters of trapped by high tide, missing in the sea, ships to hit the reef, collide or even capsize, causing oil spills. In response to these disasters around Taiwan water, Taiwan maritime disaster prevention and environmental information service platform has been developed after nearly 3 years technological R&D under commissioned and supported by Central Weather Bureau (4-year project, 2017-2020). In order to confirm the rationality of these products, the verification were done through the past maritime disaster events.

As traditional, static maps have a limited exploratory capability, GIS and geovisualization allow for more interactive maps and display on a computer or smartphone, including the ability to explore different layers of the map, to zoom in or out, and to change the visual appearance of the map. Further, geographic information infrastructures need to be integrated with the database of observations and predictions to ensure that government agencies have timely access to real time geographic information so that decisions on sustainability and disaster resilience can be effectively done. Visualize each warning (or inquiry) information through a GIS system in this study, including coastal tideline forecast, tracking drifting objects, coastal swell warning, historical typhoon wave and storm surge query, marine meteorology information for vessel route, ship sailing safety warning and oil spill tracking etc. will increase the ability of implement early warning and prevention for various maritime disaster events, effectively reduce the losses caused by various disasters. For instance, coastal swell warning to improve the safety of coastal recreation through warning colours; the ship sailing safety warning can instantly provide the impact of future wave conditions on various types of vessels to improve the safety of navigation operations.
Testing the simulation skill of hydrological models under transient climate conditions for European case studies
Authors: Pasten-Zapata Ernesto , Royer-Gaspard Paul , Pimentel Rafael , Sonnenborg Torben O. , Lemoine Anthony , Pérez-Palazón María José , Schneider Raphael , Photiadou Christiana
Published: March 2020

Commonly, the analysis of climate change impacts on hydrology involves a series of steps that begin with a General Circulation Model followed by the application of a downscaling or bias correction method and then coupling the climate outputs to a hydrological model. Nevertheless, frequently the hydrological models employed in these analyses are not tested to assess their skill to simulate the hydrology of a catchment under changing climate regimes. We evaluate such skill by applying a Differential Split Sampling Test (DSST) using the available observations. The models are calibrated during the three most extreme dry (or wet) years and evaluated on the three most wet (or dry) years. The DSST is applied on three catchments located across Europe: Denmark, France and Spain. This spatial distribution allows us to evaluate the method on diverse climatic and hydrological regimes. Furthermore, the DSST is applied to three different models in each of the catchments and case-specific metrics are evaluated to determine the practical usefulness of the models. Based on the DSST results, we assign a weight to the hydrological models and drive them with six Euro-CORDEX Regional Climate Models to assess climate change scenarios for the case-specific metrics. This methodology allows us to increase the confidence of our projections considering the hydrological model uncertainty for transient climatic conditions.
Effect of joint assimilation of GRACE and discharge observations on simulated water storages and fluxes
Authors: Schulze Kerstin , Kusche Jürgen , Engels Olga , Döll Petra , Shadkam Somayeh , Niemann Christoph
Published: March 2020

Several applications, from water resource management to the prediction of extreme events, require a realistic representation of the global water cycle. Global hydrological models simulate continental water fluxes and individual storages. However, they poorly reproduce observations of discharge and total water storage anomalies (TWSA). To improve the realism of the simulations, TWSA derived from the Gravity Recovery and Climate Experiment (GRACE) mission are usually assimilated into hydrological models.
However, while assimilating GRACE-TWSA yields more realistic TWSA simulations, it is not clear how it affects the simulation of individual storages and fluxes. Therefore, assimilating discharge, in-situ or derived from satellite-altimetry, has been suggested to improve simulated discharge which is especially important for ungauged parts of basins.

In this study, we jointly assimilate GRACE-TWSA and discharge observations and, for the first time, simultaneously calibrate the model parameters in order to improve the simulation skills of the model beyond the observational time frame. For this, we couple the WaterGAP 2.2d model with the Parallel Data Assimilation Framework and apply an Ensemble Kalman Filter for the Mississippi River Basin from 2003 to 2016. Furthermore, we compare our results to single-data assimilation and validate them against discharge observations that were not used for calibration/assimilation. Additionally, we analyze the effect of the calibrated parameters on the model’s realism.
Photochemistry of toluene under high NOx, NH3 and humid conditions in the presence of inorganic seed particles: a smog chamber study for urban haze formation at East Asia
Authors: Lim Yong , Do Duong , Jin Hyun , Lee Jiwon , Kim Jin Young
Published: March 2020

High–concentration particulate matter (PM) at East Asia threatens human health and potentially alters climate. High levels of SO2, NOx and NH3 emissions attribute the formation of inorganics including sulfates, nitrates and ammoniums in PM. Consequently, PM contains a large fraction of these inorganics, and aerosol liquid water (ALW) is considered to promote inorganic PM formation. A thermodynamic model has been used to estimate inorganic concentrations and a pH of PM because PM can be viewed as an ammonium-sulfate-nitrate-water system, which maintains thermodynamic equilibriums between the gas and particle phase and in the aqueous phase within particles. However, gas–particle partitioning of semivolatile inorganic species (i.e., NH3–NH4 + and HNO3–NO3-) particularly influenced by organics and aqueous-phase secondary organic aerosol (aqSOA) formation in PM through multiphase chemistry are not well understood.

We conducted smog chamber experiments for OH-radical initiated reactions of toluene in the presence of ammonium sulfate seed particles under high NOx, NH3 and humid conditions, which were similar to high-concentration haze conditions at Seoul, Korea. Measurements of inorganic concentrations in particles agree well with outputs of thermodynamic model simulations. The nitrate increase in seed particles is most prominent because ALW enhances the uptake of total HNO3 photochemically formed from NOx. We identified methylglyoxal as a precursor for aqSOA formation. It appears that organics attribute ALW formation under deliquescence relative humidity for inorganic salts. We further investigated the response of particle mass concentrations to various NOx concentrations, which can be useful for NOx controls for PM reduction.
A Nonlinear Static Procedure for the Design and Assessment of Buildings to Tsunami
Authors: Baiguera Marco , Rossetto Tiziana
Published: March 2020

Many coastal regions lying on subduction zones are likely to experience the catastrophic effects of cascading earthquake and tsunami observed in recent events. The response of the structure to tsunami is difficult to quantify through damage observations from past events, which often provide information on the combined effects of both perils. Hence, the use of analytical methodologies is fundamental. The authors have recently proposed a nonlinear static pushover procedure for the design and assessment of structures for tsunami within the framework of ASCE 7-16 provisions. The latter offer a comprehensive and practical methodology for the design of structures for tsunami loads and effects. While they provide prescriptive tsunami loading and design requirements, they also permit the use of performance-based analysis tools. However, the specifics of load application protocol, and system and component evaluation are not specified. Through the proposed approach, the user can estimate the effective lateral-resisting capacity of a building. In addition, by applying the component loading procedure, the user can identify the structural elements that may need to be strengthened to meet the code acceptance criteria. For this purpose, a prototypical reinforced concrete multi-storey building exposed to high tsunami hazard in the USA Northwest Pacific coast is assessed. Based on the acceptance criteria of ASCE 7-16 provisions, the lateral-load resisting system needs to be strengthened to resist tsunami loading. Overall, the use of the tsunami nonlinear static analysis procedure is found to significantly reduce the extra-costs associated with tsunami strengthening of the building.
MiniPINS - Miniature Planetary In-situ Sensors
Authors: Genzer Maria , Hieta Maria , Kestilä Antti , Haukka Harri , Arruego Ignacio , Apéstigue Victor , Manfredi Jose Antonio , Ortega Cristina , Dominiguez Manuel , Espejo Servando , Guerrero Héctor , Palin Matti , Kivekäs Jarmo , Koskimaa Petri , Talvioja Matti
Published: March 2020

MiniPINS is an ESA study led by the Finnish Meteorological Institute to develop and prototype miniaturised surface sensor packages (SSPs) for Mars and the Moon. The study aims at miniaturising the scientific sensors and subsystems, as well as identifying and utilizing commonalities of the packages, allowing to optimise the design, cut costs and reduce the development time. We present the Preliminary Mission Plan and possible concepts for the landers for this mission. 

The Mars SSP will be a small 25 kg penetrator deployed from Mars orbit. Maximally four (4) penetrators will be carried to the Martian orbit by an Orbiter and the Orbiter will be oriented for deployment of each penetrator. In the Martian atmosphere the penetrators undergo aerodynamic braking until they reach the target velocity for entering the Martian surface. 

The SSPs will start their scientific observations after landing and stay stationary throughout their mission (2 years). The SSPs have an ambitious science program to study for example the Martian atmosphere, seismology, magnetic field and chemistry. Theri payloads consist of a camera, a visual spectrometer, a meteorological package, an accelerometer, thermoprobes, a magnetometer, a chemistry package and a radiation monitor. The SSP will also provide positioning signal and communications link to the Orbiter. 

The Moon SSP will be a miniature 5 kg station deployed on the Moon surface by a rover. Maximum four (4) SSPs are deployed with low velocity and small impact depth (max. 0.05 m). All SSPs can be deployed from a single rover on the same sortie. The SSPs will start their scientific observations after landing and study for example radiation, seismology, magnetic field and chemistry. SSP will also provide communications link either to the rover or to a relay orbiter. 

Both Mars and Moon SSPs will be miniaturised, light and robust, and still capable of surviving high G loads and extreme thermal environments. SSPs are capable of working on the surface of Mars or Moon and to produce high quality science data with state of art instrumentation. The output of this work will enable ESA to prepare and plan for technology development programs required to implement such ambitious planetary missions. 
Holocene sea-level changes in the Spermonde Archipelago, Indonesia: implications for vertical land movements
Authors: Rovere Alessio , Bender Maren , Mann Thomas , Stocchi Paolo , Kneer Dominik , Schöne Tilo , Illigner Julia , Jompa Jamaluddin
Published: March 2020

We surveyed the elevation and age (14C) of paleo sea-level indicators in five islands of the Spermonde Archipelago. We describe 24 new sea-level index points from fossil microatolls, and we compare our dataset with both previously published proxies and sea-level predictions from a set of 54 Glacial Isostatic Adjustment (GIA) models, using different assumptions on both ice melting histories and mantle structure and viscosity. We then investigate the implications of our data and models in terms of vertical land movements in the study area, with two main results.

First, data from the heavily populated island of Barrang Lompo are significantly lower (ca. 80 cm) than those at all the other islands. In absence of instrumental data (e.g., GPS or tide gauges) in any of the islands, we advance the hypothesis that this difference may be due to groundwater extraction and loading of buildings on Barrang Lompo, that would cause this island to subside at rates in the order of ~3-11 mm/a.

Second, Common Era data (0-400 a BP) seem to indicate that the islands in the archipelago may be affected by tectonically-driven vertical land motions in the order of -0.88±0.61 mm/a (1-sigma), albeit slight uplift cannot be excluded. Different assumptions on vertical land motions affect, in turn, the assessment of which GIA model shows the best match with Late Holocene (ca. 4-5 ka) sea level data. Tectonic stability or slight uplift would favor iterations of ANICESELEN (De Boer et al., 2014), while subsidence would cause the sea level data to fit better with iterations of ICE-6G (Peltier et al., 2015).

References

De Boer, Bas, Paolo Stocchi, and Roderik Van De Wal. A fully coupled 3-D ice-sheet-sea-level model: algorithm and applications." Geoscientific Model Development 7.5 (2014): 2141-2156.

Peltier, W. R., D. F. Argus, and R. Drummond. Space geodesy constrains ice age terminal deglaciation: The global ICE‐6G_C (VM5a) model. Journal of Geophysical Research: Solid Earth 120.1 (2015): 450-487.

Acknowledgments

This project is funded by SEASCHANGE (RO-5245/1-1) and HAnsea (MA-6967/2-1) from the Deutsche Forschungsgemeinschaft (DFG), part of the Special Priority Program (SPP)-1889 "Regional Sea Level Change and Society". Parts of this study are under review in Climate of the Past (https://www.clim-past-discuss.net/cp-2019-63/)
Imaging the rupture process of recent earthquakes using backprojection of local high frequency records
Authors: Fountoulakis Ioannis , Evangelidis Christos , Ktenidou Olga-Joan
Published: March 2020

The seismic source spatio-temporal rupture processes of events in Japan, Greece and Turkey are imaged by backprojection of strong-motion waveforms. Normalized high-frequency (> 2Hz) S-waveforms from recordings on dense strong-motion networks are used to scan a predefined 3D source volume over time. 

Backprojection is an alternative novel approach to image the spatio-temporal earthquake rupture. The method was first applied for large earthquakes at teleseismic distances, but is nowadays also used at local distances and over higher frequencies. The greatest advantage of the method is that processing is done without any a-priori constraints on the geometry, or size of the source. Thus, the spatio-temporal imaging of the rupture is feasible at higher frequencies (> 1Hz) than conventional source inversion studies, even when the examined fault geometry is complex. This high-frequency energy emitted during an earthquake is of great importance in seismic hazard assessment for certain critical infrastructures. The actual challenge in using high-frequency local recordings is to distinguish the local site effects from the true earthquake source content - otherwise, mapping the former incorrectly onto the latter limits the resolvability of the method. It is not straightforward to remove the site effect component or even to distinguish good reference stations from amid hard-soil and rock sites. In this study, the advantages and limitations of the method are explored using waveform data from well-recorded events in Japan (Kumamoto Mw7.1, 2016), Turkey (Marmara Mw6.4, 2019) and Greece (Antikythera Mw6.1, 2019). For each event and seismic array the resolution limits of the applied method are explored by performing various synthetic tests.
Solar flare forecasting model using 3D magnetic field data
Authors: Huang Xin
Published: March 2020

Solar flares originate from the release of the energy stored in the magnetic field of solar active regions. Generally, the photospheric magnetograms of active regions are used as the input of the solar flare forecasting model. However, solar flares are considered to occur in the low corona. Therefore, the role of 3D magnetic field of active regions in the solar flare forecast should be explored. We extrapolate the 3D magnetic field using the potential model for all the active regions during 2010 to 2017, and then the deep learning method is applied to extract the precursors of solar flares in the 3D magnetic field data. We find that the 3D magnetic field of active regions is helpful to build a deep learning based forecasting model.
Crustal structure of the Central Alborz, Iran from inter-event interferometry
Authors: Afra Mahsa , Shirzad Taghi , Braunmiller Jochen , Rahimi Habib , Naghavi Mojtaba
Published: March 2020

Seismic interferometry can be used to turn earthquakes into virtual seismic sensors. Cross-correlation of seismic traces from two earthquakes recorded at the same actual sensor and summation of cross-correlations from many actual sensors result in the (strain) Green’s function between the two earthquakes. This simple concept provides an exciting new way for high-resolution imaging of subsurface structures in areas with poor instrument coverage. We test and apply this method to the Central Alborz region of Iran where we can compare results with regular local earthquake tomography. We first extracted the Rayleigh wave group velocities (U) from the Green’s functions and then inverted them for the upper crustal Rayleigh wave maps. We used vertical seismograms from 819 well-located Mw<4 earthquakes with vertical and horizontal location uncertainties of less than 2.5 km recorded between January 2006 and May 2019. The recordings are from seismic stations operated by the Iranian Seismological Center, the International Institute of Earthquake Engineering and Seismology, and the Tehran Disaster Management and Mitigation Organization. Pre-processing of each seismic trace consisted of removing the mean, detrending, instrument response correction, and 1-20 s band-pass filtering. We cross-correlated event-pairs at all available actual sensors and stacked the cross-correlations to obtain the inter-event empirical Green’s function (EGF); we used the phase weighted stacking procedure to enhance the signal-to-noise ratio of the EGF. We then applied the classical FTAN method to calculate the group velocities from the Rayleigh wave dispersion measurements. Cross-correlations, stacking and dispersion analysis were performed for all available event-pairs. Finally, we inverted the dispersion measurements to obtain group velocity maps using the Fast Marching Surface-Wave Tomography method. The resulting group velocity maps indicate a thick layer of low velocity material near the junction of the Mosha-North Tehran faults, a low velocity anomaly related to the Damavand Volcano, and abrupt transitions from high to low velocity anomalies associated with the Mosha fault.
How valuable are citizen science data for a space-borne crop growth monitoring? – The reliability of self-appraisals
Authors: Truckenbrodt Sina C. , Klan Friederike , Borg Erik , Missling Klaus-Dieter , Schmullius Christiane C.
Published: March 2020

Space-borne Earth Observation (EO) data depicting vegetation covered land surfaces contain insufficient information for an unambiguous interpretation of the spectral signal in terms of variables that characterize the vegetation state (e.g., leaf area index, leaf chlorophyll content and proportion of senescent material). For the retrieval of vegetation properties from EO data, an optimal estimate of the state variables needs to be found. The uncertainty of such an estimate can be reduced by combining EO data and in situ data. Information provided by citizens represents a valuable and mostly inexpensive source for in situ data. Since the quality of such data can be diverse, the consideration of uncertainties is of great importance.

In this contribution, we present a concept for the elicitation of local knowledge from citizens with respect to the application of management practices (e.g., sowing and harvesting date, irrigation) and the instantaneous state of crops. The concept includes the acquisition of in situ data as well as an uncertainty assessment (precision and/or accuracy). The latter involves a profiling in which inherent uncertainties are quantified for individual citizens. This concept was tested for agricultural fields of the Durable Environmental Multidisciplinary Monitoring Information Network (DEMMIN) test site in Northeast Germany. Within the frame of several field seminars, students were requested to assess management practices and the instantaneous state of crops. Furthermore, they assessed their own ability to create valid data. They filled in pseudonymized questionnaires from which we created corresponding datasets. At the same day, field data were collected with appropriate equipment and can be used as reference against which student estimates can be compared. The level of compliance between estimated and measured data was determined on an individual basis.

The results of this analysis will be presented. Conclusions will be drawn regarding the ability of the students to evaluate their own skills. In addition, we will demonstrate an approach for a digital ascertainment of in situ data. In the future, this approach will be used to collect in situ data for the setup of refined prior information within the frame of the Earth Observation Land Data Assimilation System (EO-LDAS).
Global Sensitivity Analysis of Optimal Climate Policies
Authors: Miftakhova Alena
Published: March 2020

A major tool that supports climate policy decisions, integrated assessment models are highly vulnerable to their initial assumptions and calibrations. Despite the broad literature rich in both single-model and multi-model sensitivity analyses, universal, well-established practices are still missing in this field. This paper endorses structured global sensitivity analysis (GSA) as an indispensable routine in climate–economic modeling. An application of a high-efficiency GSA method based on polynomial chaos expansions to DICE provides two insights. First, only global and comprehensive—as opposed to local or selective—sensitivity analysis delivers a trustworthy picture of the uncertainty propagated through the model. Second, careful treatment of the model’s structure throughout the analysis reconciles the results with established analytical insights—enhancing these insights with more details. The efficient GSA method provides a comprehensive decomposition of the uncertainty in a model’s output while minimizing computational costs, and is hence potentially applicable to models of higher complexity.
In situ spacecraft observations of structured electron diffusion regions during magnetic reconnection
Authors: Cozzani Giulia , Retinò Alessandro , Califano Francesco , Alexandrova Alexandra , Khotyaintsev Yuri , André Mats , Catapano Filomena , Fu Huishan , Le Contel Olivier , Vaivads Andris , Ahmadi Narges , Breuillard Hugo ,   MMS Team
Published: March 2020

Magnetic reconnection is a fundamental energy conversion process in plasmas. It occurs in thin current sheets, where a change in the magnetic field topology leads to rapid heating of plasma, plasma bulk acceleration and acceleration of plasma particles. To allow for magnetic field reconfiguration, both ions and electrons must be demagnetized. The ion and electron demagnetization  take place in the ion and electron diffusion regions respectively, in both cases at kinetic scales. For the first time, Magnetospheric Multiscale (MMS) spacecraft observations, at inter-spacecraft separation comparable to the electron inertial length, allow for a multi-point analysis of the electron diffusion region (EDR). A key question is whether the EDR has a homogeneous or patchy structure. 

Here we report MMS observations at the magnetopause providing evidence of inhomogeneous current densities and energy conversion over a few (∼ 3 de) electron inertial lengths suggesting that the EDR can be structured at electron scales. In particular, the energy conversion is patchy and changing sign in the vicinity of the reconnection site implying that the EDR comprises regions where energy is transferred from the field to the plasma and regions with the opposite energy transition, which is unexpected during reconnection. The origin of the patchy energy conversion appears to be connected to the large ve,N ∼ ve,M directed from the magnetosphere to magnetosheath. These observations are consistent with recent high-resolution and low-noise kinetic simulations of asymmetric reconnection. Patchy energy conversion is observed also in an EDR at the magnetotail, where the inter-spacecraft separation was ∼ 1 de. Electric field measurements are different among the spacecraft suggesting inhomogeneities at the electron scale. However, in this case the current density appear homogeneous in the EDR suggesting that the structuring may be sourced from a different kind of electron dynamics in the magnetotail.
Representing the Urban Heat Island Effect in Future Climates
Authors: Burgstall Annkatrin , Casanueva Ana , Hertig Elke , Fischer Erich , Knutti Reto , Kotlarski Sven
Published: March 2020

An increasing fraction of people living in urban areas and the expected increase in long lasting heat waves highlight the important role of urban climates in terms of future climate change impacts, especially with relation to the heat-health sector. Due to the urban heat island (UHI) effect and its (generally) increased intensity particularly during nighttime, people living in urban areas happen to be more affected by heat-related discomfort and health risks than those in non-urban regions. In this contribution, temperatures of both rural and urban sites (station couples) in Switzerland and Southern Germany are analyzed, using (i) observed as well as (ii) bias-corrected and downscaled climate model data for daily minimum (tmin) and daily maximum temperature (tmax) to account for the UHI in future climates. As meteorological data are often restricted to locations of long-term measurements at rural sites only, they need to be transferred to urban sites first. For this purpose, the well-established quantile mapping technique (QM) is tested in a two-step manner. The resulting products are urban time series at daily resolution for tmin and tmax. By analyzing the temperature differences of the observed climate at rural sites and their respective urban counterparts and by assuming a stationary relationship between both, we can represent the UHI in future climates, which is quantified in terms of heat indices based on tmin and tmax (tropical nights, summer days, hot days).

The QM performance is evaluated using long-term weather station data of a Zurich station couple in a comprehensive cross-validation framework. Results reveal a promising performance in the present-day climate, given very low biases in the validation.

Applying the proposed method to the employed station couples, projections indicate distinct urban-rural temperature differences (UHI) during nighttime (considering the frequency of tropical nights based on tmin) compared to weak differences during the day (considering the frequency of summer days and hot days based on tmax). Moreover, scenarios suggest the frequency of all indices to dramatically rise at the urban site by the end of the century under a strong emission scenario (RCP8.5): compared to the rural site, the number of tropical nights almost doubles while the number of summer days reveals about 15% more days at the urban site when focusing on the station couple in Zurich and the late scenario period. The lack of nighttime relief, indicated by tmin not falling below 20°C (i.e. a tropical night), is especially problematic in terms of human health and makes the study of the urban climate in general and the UHI effect in particular indispensable.
Sensitivity of high-resolution precipitation to physics parameterization options in WRF over equatorial regions
Authors: Messmer Martina , González-Rojí Santos J. , Raible Christoph C. , Stocker Thomas F.
Published: March 2020

Precipitation patterns and climate variability in East Africa and Western South America present high heterogeneity and complexity. This complexity is a result of large-scale and regional controls, such as surrounding oceans, lakes and topography. The combined effect of these controls has implications on precipitation and temperature, and hence, on water availability, biodiversity and ecosystem services. This study focuses on the impact of different physics parameterization in high-resolution experiments performed over equatorial regions with the Weather Research and Forecasting (WRF) model, and how these options affect the representation of precipitation in those regions.

As expected, weather and climate in equatorial regions are driven by physical processes different to those important in the mid-latitudes. Hence, it is necessary to test the parameterizations available in the WRF model. Several sensitivity simulations are performed over Kenya and Peru nesting the WRF model inside the state-of-the-art ERA5 reanalysis. A cascade of increasing grid resolutions is used in these simulations, reaching the spatial resolutions of 3 and 1 km in the innermost domains, and thus, convection permitting scales. Parameterization options of the planetary boundary layer (PBL), lake model, radiation, cumulus and microphysics schemes are changed, and their sensitivity to precipitation is tested. The year 2008 is simulated for each of the sensitivity simulations. This year is chosen as a good representative of precipitation dynamics and temperature, as it is neither abnormally wet or hot, nor dry or cold over Kenya and Peru. The simulated precipitation driven by the ERA5 reanalysis is compared against station data obtained from the WMO, and over Kenya additionally against observations from the Centre for Training and Integrated Research in ASAL Development (CETRAD).

Precipitation is strongly underestimated when adopting a typical parameterization setup for the mid-latitudes. However, results indicate that precipitation amounts and also patterns are substantially improved when changing the cumulus and PBL parameterisations. This strong increase in the simulated precipitation is obtained when using the Grell-Freitas ensemble, RRTM and the Yonsei University schemes for cumulus, long-wave radiation and planetary boundary layer, respectively. During some summer months, the accumulated precipitation is improved by up to 100 mm (80 %) compared to mid-latitudes configuration in several regions of the domains (near the Andes in Peru and over the flatlands in Kenya). Additionally, because the 1- and 2-way nesting options show a similar performance with respect to precipitation, the 1-way nesting option is preferred, as it does not overwrite the solutions in the parent domains. Hence, discontinuous solutions related to switching off the cumulus parameterization can be avoided.
Variability of boreal spring Hadley circulation over the Asian monsoon domain and its relationship with tropical SST
Authors: Wang Yaqi , Feng Juan , Li Jianping , An Ran , Wang Lanning
Published: March 2020

The variability of boreal spring Hadley circulation (HC) over the Asian monsoon domain over the last four decades is explored. The climatological distribution of the regional HC is symmetric of the equator, with the ascending branch around the equator and sinking branch around the subtropics in each hemisphere. The first dominant mode (EOF1) of the regional HC is equatorial asymmetric, with the main body in the Southern Hemisphere (SH) and the ascending branch to the north of the equator. This mode is mainly characterized by interannual variation and is related to El Niño-Southern Oscillation (ENSO). Significant negative sea surface temperature (SST) anomalies are observed over the tropical Indian Ocean (TIO) along with the development of La Niña events; however, the magnitude of SST anomalies in the southern Indian Ocean is greater than that in the northern counterpart, contributing to EOF1 formation. The spatial distribution of the second dominant mode (EOF2) is with the main body lying in the Northern Hemisphere (NH) and the ascending branch located to the south of the equator. The temporal variation of this mode is connected to the warming of the TIO. The warming rate of the southern TIO SST is faster than that in the northern counterpart, resulting in the southward migration of the rising branch. The above result indicates the critical role of the meridional distribution of SST on the variability of the regional HC.
Development of ground penetrating radar for enhanced root phenotyping and carbon sequestration
Authors: Hays Dirk , Wolfe Matt , Dobreva Iliyana , Ruiz Henry
Published: March 2020

Currently atmospheric carbon has reached 405 ppm or 720 GtC.  As is widely known, this increasing atmospheric carbon dioxide, methane and nitrous oxide are primary contributing factors in increasing global temperatures.  Current measurements show that sources of emission such as the burning of fossil fuels contributes 9.9 GtC/yr, while land use change contributes 1.5 GtC/yr. We have identified that crops possessing a subsurface rhizome in particular, in addition to high root biomass, are essential and capable of increasing crop derived soil carbon sequestration by 10-fold.  If the presence of a high biomass rhizome were bred into the world’s major grain crops wheat, rice, maize, barley, sorghum and millets and grown worldwide in no-tillage conditions, these crops could sequester and offset current carbon emissions by 9Gt carbon on a yearly basis. We have developed a new ground penetrating radar instrument and analytical software, which will be presented, as a needed for high throughput non-destructive phenotyping, selection and speed breeding new high root biomass cultivars of the worlds major cultivated crops and forages as a key component for crop-based carbon sequestration driven climate change mitigation. 
The WegenerNet 3D weather and climate research facility: A unique open-air laboratory for high-resolution precipitation studies
Authors: Fuchsberger Jürgen , Kirchengast Gottfried , Bichler Christoph
Published: March 2020

The WegenerNet Feldbach Region is a unique weather and climate observation facility
comprising 155 meteorological stations measuring temperature, humidity, precipitation,
and other parameters, in a tightly spaced grid within a core area of 22 km × 16 km
centered near the city of Feldbach (46.93°N, 15.90°E).
With its stations every about two square-km (area of about 300 square-km in total),
and each station with 5-min time sampling, the network provides regular measurements
since January 2007. In 2020, the station network will be expanded by three major
new components, converting it from a 2D ground station network into a 3D open-air
laboratory for weather and climate research at very high resolution.
The following new observing components will start operations by spring 2020:

A polarimetric X-band Doppler weather radar for studying precipitation parame-
ters in the troposphere above the ground network, such as rain rate, hydrometeor
classification, Doppler velocity, and approximate drop size and number. It can
provide 3D volume data (at about 1 km × 1 km horizontal and 500 m vertical res-
olution, and 5-min time sampling) for moderate to strong precipitation. Together
with the dense ground network this allows detailed studies of heavy precipitation
events at high accuracy.

An azimuth-steerable microwave/IR radiometer for vertical profiling of temperature,
humidity, and cloud liquid water in the troposphere (with 200 m to 1 km vertical
resolution, and 5-min time sampling), also capable of measuring integrated water
vapor (IWV) along line-of-sight paths towards Global Navigation Satellite System
(GNSS) satellites.

A water vapor mapping high-resolution GNSS station network, named GNSS StarNet,
comprising six ground stations, spatially forming two star-shaped subnets (one
with ∼10 km interstation distance, and one embedded with ∼5 km distance), for
providing slant IWV, vertical IWV, and precipitable water, among other parame-
ters, at 5-min time sampling.

We will present a detailed overview of the new components, their location, specifica-
tion, and output data products.
Multi-sensor satellite imagery analysis of the growth and collapse of a littoral lava dome during the 2018/19 eruption of Kadovar Volcano, Papua New Guinea
Authors: Plank Simon , Walter Thomas , Martinis Sandro , Cesca Simone
Published: March 2020

Growing volcanic islands and lava domes become structurally unstable, associated with sectoral collapses, explosive volcanism and related hazards. We present the rare case of a growing and collapsing lava dome at Kadovar Volcano. This small inhabited volcanic island is part of the Schouten Islands, at the western end of the Bismarck Volcanic Arc, north of Papua New Guinea. The first confirmed historical eruption at Kadovar began on 5 January 2018 and was monitored by synthetic aperture radar (SAR), thermal and optical satellite sensors. Our analysis of the different remote sensing data shows that Kadovar began a new episode of volcanic activity at the central crater and then also at the eastern coast of the island, where we monitored the birth of a new emerging lava dome. We analyse changes occurring on the island and the littoral lava dome and identify that after dome growth (with an area of ~2,000 m² area week), parts of the island and about 80% of the littoral lava dome collapsed eastwardly into the ocean on 9 February 2018. This collapse caused small tsunami waves that hit the neighbouring islands. The littoral lava dome then re-grew at a slower rate (of ~285 m² per week) and reached a final area of ~40,000 m² by 2 May 2018, which corresponds to an estimated subaerial volume of the lava dome of ~400,000 m³. This study provides details on the rapid growth and collapse of a peripheral lava dome and a destabilization episode in an island and dome sector. The importance of remote sensing data for the monitoring and investigation of remote volcanic islands is demonstrated.
Climate change and the carbon cycle of frozen floodplains.
Authors: van Huissteden Ko , Teshebaeva Kanayim , Cheung Yuki , Noorbergen Hein , van Persie Mark
Published: March 2020

Permafrost-affected river plains are highly diverse in discharge regime, floodplain morphology, channel forms, channel mobility and ecosystems. Frozen floodplains range from almost barren systems with high channel mobility, to extensive wetland areas with low channel mobility, abundant abandoned channels, back-swamps and shallow floodplain lakes. Floodplain processes are increasingly affected by climate-induced changes in river discharge and temperature regime: changes in the dates of freeze-up, break-up and spring floods, and changes in the discharge distribution throughout the year.

In permafrost floodplains, changes in flooding frequency, flood height and water temperature affect active layer thickness, subsidence and erosion processes. Data from the Northeast Siberian Berelegh river floodplain (a tributary to the Indigirka river) demonstrate that increasing spring flood height potentially causes permafrost thaw, soil subsidence and increase of the floodplain area. INSAR (interferometric synthetic aperture radar) data indicate that poorly drained areas in this region are affected by soil subsidence. Morphological evidence for subsidence of the river floodplain is abundant, and river-connected lakes show expansion features also seen in thaw lakes.

These floodplain wetland ecosystems are also affected by changes in the discharge regime and permafrost. On the one hand, floodplains are sites of active sedimentation of organic matter-rich sediments and sequestration of carbon. This carbon is derived from upstream erosion of permafrost and vegetation, and from autochthonous primary production. Nutrient supply by flood waters supports highly productive ecosystems with a comparatively large biomass.

On the other hand, these ecosystems also emit high amounts of CH4, which may be affected by flooding regime. In the example presented here, the CH4 emission from floodplain wetlands is about seven times higher that the emission from similar tundra wetlands outside the floodplain.

The dynamic nature of floodplains hinders carbon and greenhouse gas flux measurements. Better quantification of greenhouse gas fluxes from these floodplains, and their relation with river regime changes, is highly important to understand future emissions from thawing permafrost. Given the difficulties of surface greenhouse gas flux measurements, recent remote sensing material could play an important role here.
Iron Chemical Analysis of Spodosols to Date Last Pleistocene-Holocene. The Example of the Italian Central Alps.
Authors: Longhi Alessandro , Guglielmin Mauro
Published: March 2020

The deglaciation of the Italian Central Alps is still discussed and not well known, especially when we consider the Late Pleistocene-Early Holocene. This study will use different fraction of the iron content of paleo-spodosols to date the time of the deglaciation of three areas in the Central Italian Alps (Gavia, Stelvio and Val Viola). Relying on a first soil distribution analysis and on geomorphological evidences, we opened and described 24 soil pits and from each A and B horizon we collected at least 1 kg of sample to do some basic soil physical analysis: granulometry, water content, pH and loss on ignition. The oxalate extractable iron fraction and the dithionite extractable iron fraction have been determined with standard lab procedures, the total iron content has been determined using a SEM/EDX analysis. We calculated the Iron Crystallinity Ratio, defined as the difference between the dithionite extractable iron fraction and the oxalate extractable iron fraction, normalized on the total iron content. The Iron Crystallinity Ratio gives us a relative age of the soil formation: using data from radiocarbon dating and from cosmogenic dating, we calibrated the Iron Crystallinity Ratio with absolute ages. With the obtained functions, which showed a good fitting, we calculated ages between 15809 years and 5490 years in the Gavia area, between 11760 years and 7237 years in the Stelvio area and between 14668 years and 7096 years in the Val Viola area.