bluuebunny/crossref_metadata_2025 huggingface dataset:
Will global climate change make people more comfortable? A scenario analysis based on the weather preference index
Authors: Fang Zihang
Published: March 2022

Weather conditions refer to the state of the atmosphere at a specific time in a specific place. Changes in weather conditions influence human well-being by affecting the productivity of ecosystems and the quality of life. Climate change can affect weather conditions by changing the trend, frequency and extreme values of meteorological elements such as temperature, precipitation and humidity. The changes in weather conditions caused by climate change have had a serious impact on human well-being and will continue in the future. Therefore, assessing the impact of future climate change on weather conditions is of great significance for addressing climate change and promoting global sustainable development. However, the commonly used assessment indicators only describe the changes of weather conditions and do not consider the population exposure and people’s perceptions to the changes of weather conditions, which limits the significance of the evaluation results in improving human well-being and promoting regional sustainable development. Thus, taking the weather preference index (WPI) as the evaluation index and combined with the scenario framework provided by the Scenario Model Intercomparison Project (ScenarioMIP), we evaluated the impact of global climate change on weather conditions under different scenarios from 2015 to 2100. First, we quantified global WPI from 1980 to 2015 based on global meteorological observation data. Then, combined with global climate model data, we analyzed global WPI from 2015 to 2100 under different scenarios. Finally, we used trend analysis to evaluate the impact of global climate change on weather conditions. We found that global weather conditions will deteriorate from 2015 to 2100, and the global average WPI will change at a rate of -0.05/10a. At the same time, we also found that more than 60% of the world's urban residents will live in regions with deteriorated weather conditions in the future. Under any scenario, there will still be 1.46 billion urban population living in regions with deteriorated weather conditions in 2100, accounting for 61.55% of the total urban population. Therefore, we suggest that countries should be as close to the narrative line of the green revival scenario (SSP1-2.6) as possible in the development process, and reduce greenhouse gas emissions by means of terminal emission control, the development of clean energy and the introduction of ultra-low emission technologies. On top of that, resilience to climate change needs to be improved by improving public infrastructure and living conditions.
Investigating the carbon biogeochemical cycle at Mt Etna
Authors: Pennisi Maddalena , D'Incecco Simone , Baneschi Ilaria , Lelli Matteo , Provenzale Antonello , Raco Brunella
Published: March 2022

The continuous acquisition of CO2 soil flux data has been started on Mt Etna in November 2021, with the aim of assessing a first balance between CO2 from volcanic and biological origin. Our long-term goal is an interdisciplinary study of volcanic, biological, ecological, biogeochemical, climatic and biogeographical aspects, including the anthropogenic impact on the environment. All aspects are integrated in the study of the so-called Critical Zone, i.e. the layer between the deep rock and the top of the vegetation where the main biological, hydrological and geological processes of the ecosystem take place. The new research activity at Mt Etna is performed within the framework of the PON-GRINT project for infrastructure enhancement (EU, MIUR), and it adds up to activities going on at Grand Paradiso National Park (Italian Alps), and Ny Alesund (Svalbard, NO, High Arctic) in the framework of the IGG-CNR Critical Zone Observatories.

During the first phase of the project, two fixed stations were installed in two sites at Piano Bello (Valle del Bove, Milo), in an area where the endemic Genista aetnensis grows. An Eddy Covariance system for net CO2 ecosystem exchange measurement and a weather station will be installed in 2022. Carbon stable isotopes data will be acquired periodically using in-situ instrumentation (i.e. Delta Ray).  The installation sites are selected after CO2 soil flux surveys around the volcano using a portable accumulation chamber. The two stations installed at Piano Bello consist of an automatic accumulation chamber fixed to the ground, a mobile lid with a diffusion infrared sensor for measuring CO2, a data logger and a sensor for measuring soil moisture and temperature. The accumulation chambers are programmed to acquire data on ecosystem respiration every hour for all day. Data are transmitted to the IGG data collection center. The new IGG-CNR Mt Etna CZO will contribute investigating CO2 fluxes at the soil-vegetation-atmosphere interface in different geological and environmental contexts. We benefit from the collaboration with the National Institute of Geophysics and Volcanology (INGV), the Ente Parco dell'Etna, and the Dipartimento Regionale dello Sviluppo Rurale e Territoriale di Catania.
A method to assess the uncertainty of Benfratello’s estimate of the irrigation deficit in a semiarid area and its GIS based application for anthropogenic and climate change scenarios
Authors: Barontini Stefano , Peli Marco , Rapuzzi Cesare , Colosio Paolo , Ranzi Roberto
Published: March 2022

Benfratello's conceptual method, to estimate the irrigation deficit for agricultural districts in semiarid or arid climate, firstly came to light in 1961. The method generalizes previous Thornthwaite (1948) and Thornthwaite and Mather (1955) water balances to assess the irrigation deficit as the difference between the maximum evapotranspiration, exerted by the plant in full irrigation conditions and traditionally estimated with the Thornthwaite formula, and the actual evapotranspiration provided by the available soil water. Since its first appearance, it has been applied to the study of many areas in Southern Italy. Due to its simplicity and to the small number of required parameters, Benfratello's method might be regarded to as an effective tool to assess the effects of climatic, landuse and anthropogenic changes on the soil water balance and on the irrigation deficit.

In the previous General Assembly we presented a GIS based application of Benfratello's method to the case study of the semiarid Capitanata plane (4550 km2, Southern Italy), which is one of the most important agricultural districts in Italy. With this contribution we present a further theoretical development of the method that allows to simply estimate in closed form the uncertainity of the calculated irrigation deficit, once known the uncertainty of the required climatic variables (temperature and precipitation). Our procedure is based on a local linearization of the core—function of Benfratello’s method, which presents the decrease of the available soil water, during the dry season, as a function of the potential soil water loss, given by the difference between the maximum evapotranspiration demand and the precipitation. The maximum evapotranspiration was in this case determined by means of the Hargraves formula, according to FAO procedure in case of limited availability of meteorological data. The estimate of the uncertainty can be easily performed in both the cases in which the field capacity is completely or only partially restored during the wet season. As a test case, the method was then applied to some sites in the Capitanata plane and extended to the whole plane through a GIS application, with fair results if compared with the required water volumes declared by the local irrigation consortium.
Exploring 2.5D magnetic reconnection due to Rayleigh-Taylor induced turbulence in solar prominences
Authors: Changmai Madhurjya , Keppens Rony
Published: March 2022

The internal dynamics of solar prominences have been observed for many decades to be highly complex, many of which also indicate the possibility of turbulence. Prominences represent large-scale, dense condensations suspended against gravity at great heights within the solar atmosphere. It is therefore of no surprise that the fundamental process of the Rayleigh-Taylor (RT) instability has been suggested as the potential mechanism for driving the dynamics and turbulence remarked upon within observations. We use the open-source MPI-AMRVAC code to construct an extremely high-resolution, 2.5D fully-resistive magnetohydrodynamic model, and employ it to explore the turbulent nature of RT-induced magnetic reconnection processes within solar prominences. The intermittent events of heating and energy dissipation are caused by magnetic reconnection. Furthermore, the strength of the mean magnetic field directed into the 2D plane, and its alignment with the plane itself, creates a system with varying turbulent behaviour. Based on low plasma beta (magnetic pressure dominant) evolution near the chromosphere and a higher value (plasma pressure dominant) evolution within the corona, the stratified numerical model generates different fluctuation statistics. Hence, we find the turbulent dynamics and prominence reconnection events to differ distinctly from those elsewhere within the solar corona.
Unveiling Convective Momentum Transport at different scales during EUREC4A
Authors: Savazzi Alessandro Carlo Maria , Nuijens Louise , de Rooy Wim , Siebesma Pier
Published: March 2022

The transport of horizontal momentum takes place at various spatial and temporal scales: from small-scale turbulence to cloud- and meso-scale circulations. This study focuses on the role of convective momentum transport (CMT) in the momentum budget in trade-wind cloud regimes with different patterns of cloud organization. Observations of the momentum budget during EUREC4A suggest that in early February, deeper convection and larger cloud structures are associated with a different profile of eddy momentum flux divergence than days with shallower cumulus humilis. Using large eddy simulation hindcasts and a mesoscale weather model, we study the profiles of eddy momentum flux associated with turbulence, convection and mesoscale flows in different cloud scenes during EUREC4A. Are turbulent, convective or mesoscale circulations responsible for a deceleration or acceleration of the mean flow? Are along-wind or cross-wind circulations more pronounced? Do the models show evidence of countergradient flux  production in the cloud layer?

 

We select a ten-day period for which the Dutch Atmospheric Large-Eddy Simulation (DALES) model is run on a 150 km x 150 km domain with a resolution of 100 m. Its boundaries are forced hourly with dynamical tendencies from the mesoscale weather model (HARMONIE), which is initialized every 24 hours from ERA5. HARMONIE is also run in a climatological mode on a 3200 km x 2000 km domain with 2.5 km resolution, in runs with shallow convective momentum transport on and off.

 

In this presentation, we first evaluate the models’ ability to reproduce the mean and evolution of the wind profiles and the momentum fluxes during the ten days, as well as the cloud organization. Second, we present and discuss the eddy momentum flux divergence that is carried by flows on different scales and evaluate its role in the momentum budget. Third, we discuss the relationship between shallow convective momentum transport and cloud organization.
Review on land subsidence and socio-hydrology of northern Java, Indonesia
Authors: Budiyono Yus , Melati Dian Nuraini , Khaerani Puspa , Yuliana Diyah Krisna , Riyandari Ritha , Riyalda Bondan Fiqi , Colombijn Freek
Published: March 2022

Northern Java coasts of Indonesia is dominated by unconsolidated Holocene alluvial deposits. Anthropogenic stresses on the area has lead to land subsidence at various rate relate to the deposition systems. This paper review reports on land subsidence in the area using the formal phrase as well as terms related to the phenomenons appeared in coastal communities. We found the formal phrase appeared decades after coastal communities has considered the impact without knowing the physical phenomenon. In addition to that, research agencies have been focusing on monitoring while national government bodies focused on mitigation infrastructures. To fill in the gap, we suggest flood risk study will help the efforts to bridge both activities. This will help local and national government to prioritize activities in to overcome negative impact of land subsidence.
Permathawing permafrost 
Authors: A. Bartsch Unnur Blær , Gísladóttir Guðrún , Grímsdóttir Harpa
Published: March 2022

Permafrost is perennially frozen ground occurring in about 24% of the exposed land surface in the northern hemisphere. The soil categorized as permafrost is named cryosol (or gelisol). Cryosol is widely spread in the Arctic, where it is continuous in the polar regions while in the sub-arctic it is discontinuous or sporadic. Iceland is located on the edge of the Arctic, and therefore permafrost can be found in many regions of the island. In addition, the frost effect is great, due to the unique climate and weather conditions and the high sensitivity of the Icelandic soil (volcanic soil – andosol). Although the distribution of permafrost is widespread it is in many respects dependent on the weather. As the climate warms, as it does now, the permafrost retreats rapidly, causing major changes in the earth’s surface. These changes can be accompanied by various dangers. In Iceland the retreat of permafrost in high mountains has led the top slopes to become unstable, leading to increased risk of landslides and similar hazards. In this project, permafrost in Iceland will be examined, more specifically the areas where permafrost is considered to be thawing and the dangers that accompany that thawing. The research area is by Strandartindur mountain in Seyðisfjörður. On the slope of Strandartindur is a rock glacier, which is in motion, but it is believed that permafrost is hidden in the ground beneath. The area is a well-known landslide area, where the source of landslides high up in Strandartindur is thick sediments that are partly considered permafrost or rock glaciers. Rock glaciers and thawing of permafrost in the vicinity and/or in the glacier threaten settlements in the area, due to landslides. This will be a threefold multidisciplinary project where aspects of natural hazards and society will be tied together; (i) data from soil thermometers and InSAR data will be examined, (ii) discussed and examined how permafrost can be included in monitoring, (iii) and how information on the dangers associated with permafrost can be disseminated to residents and the general public. The project will be useful for monitoring the hazard area at Strandartindur, while also for monitoring comparable areas in the country. It is hoped that the product of this project will be a monitoring research proposal. The result will show how best to measure permafrost, how best to monitor its thawing and how best to provide information to residents and the general public.
Regional Acceleration of the Antarctic Dynamic Ice Loss from Satellite Gravimetry
Authors: Diener Theresa , Sasgen Ingo
Published: March 2022

As large-scale circulation patterns change in the Southern Hemisphere the Antarctic ice sheet is exposed to increases in atmospheric and ocean temperatures. These climatological changes vary regionally and hold the potential to initiate processes that lead to ice sheet disintegration and sea level rise. In the Amundsen Sea region, in West Antarctica, major ice mass losses and increased ice flow can already be observed at present. Such processes are less common in East Antarctica but are also occurring in a more regionally restricted manner, for example to the glaciers feeding the Amery Ice Shelf.

The current state of the ice sheet is critical to evaluate the associated contribution to future global sea level rise. Therefore, we aim to quantify ice dynamic acceleration in Antarctica based on differencing GRACE/GRACE-FO and ERA5-SMB for the period 2002 to 2020. This indirect method provides an alternative to estimates that quantify ice stream acceleration based on satellite observations of surface ice velocity and is justified by the excellent agreement between GRACE/GRACE-FO and SMB on interannual time scales. In agreement with direct observations, our estimate identifies the Amundsen Sea embayment and the Bellingshausen Sea region in West Antarctica as the dominant source of dynamic loss and potential instability. We find that uncertainties in the SMB estimate are the dominant limitation in the accuracy of our outflow estimate. The uncertainties in our estimate can be reduced by further improvement of regional climate models. In this presentation, we introduce an alternative method to estimate dynamical acceleration, along with its uncertainty, and show its value in assessments of the state of the Antarctic ice sheet. We conclude that constraining the acceleration of ice sheet mass loss in the projection of sea level rise results in a contribution that is more than twice that of linear extrapolation to 2100.
Mitigation of surface runoff and soil erosion in potato farming
Authors: Konzett Matthias , Schmaltz Elmar , Strauss Peter
Published: March 2022

The potato is known as a particularly erosion-prone crop due to its late seed development and the unique structure of its seedbed (wide-rows). Therefore, improved tillage practices are needed in order to counteract and mitigate adverse effects of erosion.

This research evaluates the effectiveness of three mitigation measures – furrow greening, micro-dams heaped between furrows, and greened micro-dams – over a three-year study period in Lower Austria. Runoff plots were used to quantify surface runoff and collect each treatment's eroded material during precipitation events. The contents were emptied after each event, dried, weighed, and, if possible, analyzed for grain size distribution and nutrient composition. Additionally, the soil water content of the ridges and furrows and the potato yield was determined for each treatment in the 2021 field campaign to evaluate further effects of each treatment.

Results show that with a furrow greening soil erosion was reduced between 48 – 83% compared to the control treatment. By heaping micro-dams, soil erosion was reduced by 79 – 98%, and with the additional greening of micro-dams sediment yield was lowered by 94 – 99%. Micro-dams increased the water content in the furrows after a precipitation event but not in the ridges. Regarding potato yield, no significant difference was observed between treatments.

The results of this study show the potential of micro-dams to reduce on-site and off-site effects of soil erosion on sloped agricultural land. Depending on the steepness of the slope and the intensity of precipitation events, breaking of micro-dams can occur and therefore lose their mitigation effect. Through the additional greening of micro-dams, further stabilization could be reached, thus withholding precipitation events of higher intensities.
Downscaling of an unstructured-grid model for the German Bight 
Authors: Jacob Benjamin , Koch Wolfgang , Staneva Joanna
Published: March 2022

Coastal areas in the North Sea and more specifically the German Bight are subject to continuously developing activities such as, among others, wind farming, transportation, river regulations and transport. The resulting environmental changes interact with those caused by the local natural variability and interaction with the open ocean. Coastal areas are representatives of the biogeochemically most active regions, incorporating interactions between land and ocean, sediment dynamics and morphodynamics. The small temporal and spatial scales of processes are challenging for the provision of sufficient and credible high-resolution 4D observations. Therefore, the mix between modelling and observations is considered as the most efficient tool to develop up-to-date coastal products, such as predictions and estimates of coastal and estuarine states, and scientific support for activities and decision making. Thereby, one major research direction is to shorten the gap between regional ocean and coastal/estuarine modelling and to ensure a seamless interface between CMEMS and regional operational predictions. This is demonstrated in our  REST-COAST applications for the German Bight and its estuaries where we develop flexible interfaces beneficial for the CMEMS framework and coastal forecasting systems. This development is transferable to other European coastal areas and contributes to harmonizing various similar, and nor well inter-linked, activities. The downscaled model is based on the SCHISM unstructured-grid model coupled to the wind wave model WWM. The performance  of the German Bight circulation model is assessed against in-situ observations and CMEMS regional products.
Imaging the crust and the upper mantle of Cumbre Vieja volcano (La Palma, CanaryIslands) through receiver function analysis.
Authors: Ortega Víctor , D'Auria Luca
Published: March 2022

The receiver function analysis (RF) is a commonly used and well-established method to investigate subsurface crustal and upper mantle structures, removing the source, ray-path and instrument signature. RF gives the unique of sharp seismic discontinuities and information about P-wave (P) and shear-wave (S) velocity below a seismic station.

This work aims to study the crust and the upper mantle of La Palma up to 40 km depth by using RF analysis. Because of the geological context as an active island, it is expected that Mohorovičić’s discontinuity has a complex geometry under Cumbre Vieja and possibly a high anisotropy can be present. This makes the application of conventional RF function analysis difficult.

That is why in this study, we applied the frequency-domain RF inversion using multi-taper deconvolution. After that, we have applied the transdimensional approach of Bodin et al. (2012) to determine 1D profiles of P and S wave velocities in terms of probability distributions, as well as the probability of a discontinuity to be located at a given depth. This approach does not require establishing “a priori” the number of layers to be used for the inversion.

Our preliminary results allowed us to correlate the different discontinuities besides the stations we got deployed around Cumbre Vieja. We have seen at least for different layers with a significant change in their Vp/Vs ratios. Moreover, we have determined the Moho topography under Cumbre Vieja and the whole island.

These results are compared with the seismicity observed during the 2021 Cumbre Vieja eruption, mainly located at the base of the crust (10-15 km) and in the upper mantle (20-30 km), possibly indicating the presence of two magmatic reservoirs at these depths.

 

References

Bodin, T., Sambridge, M., Tkalčić, H., Arroucau, P., Gallagher, K., & Rawlinson, N. (2012). Transdimensional inversion of receiver functions and surface wave dispersion. Journal of Geophysical Research: Solid Earth, 117(B2).
Detecting Microseismicity in Jammu and Kashmir Himalaya Using Template Matching Technique
Authors: Ghosh Ayon , Vičič Blaž , Mitra Supriyo , Priestley Keith , Wanchoo Sunil Kumar
Published: March 2022

We study microseismicity in the Kashmir seismic gap from broadband data of the Jammu and Kashmir Seismological NETwork (JAKSNET) using the template-matching technique. Template-matching is done by the Python routine ‘PyMPA’ (Vuan et al. 2018) to detect new events. For templates, we use 189 earthquakes, taken from the ISC reviewed catalogue, which occurred between 2013 and 2018. We use 5 second long waveform templates by taking 2.5 s before and after the S-wave arrival. Normalized cross-correlations are calculated for each template earthquake, recorded at different channels, with continuous data from their respective recording channels. The individual cross-correlation traces are shifted according to the travel times of the template earthquake, calculated using a local 1D velocity model, and stacked to get a Network Stack Function (NSF). A detection is declared if the NSF crosses a threshold value eight times the Median Absolute Deviation. We assign the location of the template, corresponding to the detection, as the location of the newly detected event. If multiple templates detect one event, we consider the one with the maximum NSF value. After running the process, we obtain a catalog of 935 events, an immediate 5-fold increase in the number of events. We also observe two clear sequences of events in the middle of 2013 and in the start of 2016. We intend to perform a probabilistic and relative relocation of all the events to get a detailed seismotectonics of the region.
Sources of variability in the ionospheric spatio/temporal scales measured by Swarm instrument suite
Authors: Urbar Jaroslav , Spogli Luca , Cicone Antonio , Clausen Lasse , Jin Yaqi , Wood Alan , Alfonsi Lucilla , Cesaroni Claudio , Rawlings James , Kotova Daria , Høeg Per , Miloch Wojciech
Published: March 2022

The ionosphere is a dynamical system exhibiting nonlinear couplings with the other “spheres” characterizing the geospace environment. Such nonlinearity manifests also through the non-trivial, largely varying range of spatial and temporal scales. We investigate how the different scales of the in situ plasma density as provided by different data products measured by Swarm satellites relate to the same range of scales of the field-aligned currents from Swarm FAC dataset and how their intensifications reflect the various conditions of the geospace.

The present study compares the spatio-temporal variability in the topside ionosphere by leveraging on the Fast Iterative Filtering (FIF) technique. FIF is able to  reveal the hidden features of a time series, as it decomposes any nonstationary, nonlinear signals, like those provided by Langmuir probes onboard Swarm, into oscillating modes, called intrinsic mode components or functions (IMCs or IMFs), characterized by their specific frequencies. 

The instantaneous time-frequency representation of the IMFs is provided through the so-called “IMFogram” which illustrates the time development of the multi-scale processes. The IMFogram has the potentiality to show the finer details of the scale sizes which intensify during the various phases of geomagnetic storms.

This work is performed in the framework of the Swarm Variability of Ionospheric Plasma (Swarm-VIP) project, funded by ESA in the “Swarm+4D-Ionosphere” framework (ESA Contract No. 4000130562/20/I-DT).
Oblique propagation of mountain waves to the upwind side of the Andes observed by GLORIA and ALIMA during the Southtrac measurement campaign
Authors: Krasauskas Lukas , Kaifler Bernd , Friedl-Vallon Felix , Rhode Sebastian , Preusse Peter
Published: March 2022

The SOUTHTRAC measurement campaign was held in Argentina from September to Novem ber 2019 using the HALO research aircraft. One of the main goals of the campaign was gravity wave (GW) study in the region of Southern Andes: a global hotspot for GW activity. The measurements included air temperature data from the IR limb imaging spectrometer GLORIA jointly developed by FZJ and KIT, as well as an upward looking ALIMA lidar developed by DLR, and in situ instruments. GLORIA’s viewing direction can be panned between 45° and 135° with respect to the flight direction. Combining this capability with flight paths that encircle the observed atmospheric region, multiple measurements of the same air mass can be performed, allowing for 3D tomography of the atmosphere with a vertical resolution down to 250 m and horizontal resolution of around 25 km. GLORIA provides data below the flight altitude of the HALO aircraft (up to 15 km), while ALIMA observations cover the altitude range between 20 and about 60 km. During a research flight on 20-21 September, a large amplitude mountain wave was observed over the Andes. GLORIA 3D data showed a complex temperature structure with several overlapping gravity wave families at altitudes of 9 to 14 km above the mountain ridges. The amplitudes and 3D wave vectors for each of those families were determined by performing a least-squares fit of harmonic disturbances to the GLORIA temperature data. These wave parameters were then used to initialise a ray-tracer (GROGRAT ray-tracing code was used) and follow the path of the waves as they propagated upwards and away from the mountain range. The results of this study could be summarised as follows:

• Many of the waves oberved by GLORIA in the 9-14 km altitude range propagated into the regions observed by ALIMA in 25-40 km altitudes. There was very good agreement between ALIMA data and GLORIA data-initialised ray tracing results: GWs observed by GLORIA were shown to propagate into the same regions where waves were seen by ALIMA and their spectral characteristics also closely matched ALIMA observations.

• Some GWs were observed over the Pacific at the altitude of around 30 km, apparently upstream of the Andes. The origin of those waves was uncertain during the measurement campaign. Our ray-tracing results showed that these were in fact mountain waves propagating obliquely from their sources further south in the Andes mountain chain.

• Our results generally compare well with ECMWF operational analysis data, with some differences close to the critical layer at around 35-40 km altitude.

• We also present a comparison of our measurement results with the predictions of a stand-alone mountain wave model developed in FZJ.
Spatial distribution of creep on a creeping thrust fault: Joint inversion using geodetic data and repeating earthquakes 
Authors: Peng Wei , Radiguet Mathilde , Pathier Erwan , Chen Kate Huihsuan
Published: March 2022

The Chihshang fault in Taiwan serves as one of the best examples of faults with a primarily thrust component that rapidly creep at the surface (2-3 cm/yr), while it is also known to have produced magnitude 6 earthquakes. The deeper portion of this thrust fault is typically offshore, where land-based geodetic measurements are insensitive to fault slip at greater depth. The understanding of inter-seismic slip rate at depth therefore, remains elusive. Taking advantages of slip rates inferred from repeating earthquake sequences (RES) at greater depth, here we present a modified method that embeds RES derived slip rate into the neighboring fault patch for geodetic data inversion. Using the geodetic and seismological data from 2007 to 2011, we reach the higher resolution of interseismic slip rate distribution below the depth of 15 km. The inferred low coupling ratio establishes the extensive creeping area that coincides with the location of abundant repeating earthquakes and swarm events. The inferred high coupling ratio on the other hand, delineates the locked area corresponding to the co- seismic slip zone of the 2003 Mw6 Chengkung earthquake. The postseismic area however, is found to mainly overlapped with the low coupling ratio area at shallow depth (freely creeping) but not where the microseismcity, repeating and swarm events are located (partially creeping). We propose that the strongly locked area is concentrated in the middle of the fault extending from near surface to the depth of 25 km, surrounded by the creeping areas where microseismicity, repeating and swarm events are taking place. We estimate that a slip rate deficit equivalent to Mw 6.26 has accumulated annually, which may be able to generate greater than Mw 7 event over an interval of 20 years. It is thus importance, to follow up by time-dependent kinematic model in the future for better estimate of large earthquake potential in this creeping fault.
Estimation of groundwater mean residence times in a near-surface aquifer using different natural tracers (Radon-222, Sulfur-35, Tritium, and δ18O)
Authors: Schmidt Axel , Engel Michael , Mischel Simon , Radny Dirk
Published: March 2022

The residence time of groundwater is an essential parameter for water resource management. In the presented study, environmental tracers (Rn-222, S-35, H-3, δ18O) and hydrogeochemical groundwater components are used for assessing groundwater mean residence times in a near surface aquifer.

At a barrage station at the River Moselle, four groundwater monitoring wells and two surface water spots were sampled at a 4-week interval over an 18-month period. At each sampling event, isotopes as well as other hydrogeochemical parameters (e.g. water level, water temperature, oxygen, pH value and electrical conductivity) were measured and evaluated.

All tracers showed different concentrations and signatures in ground- and surface water samples. As expected, Radon showed high concentrations in groundwater (up to 25 Bq/L) and low concentrations (about 0.2 Bq/L) in surface water. The tritium content of groundwater (13 Bq/L; ~110 TU) was similar to the long-term average concentration measured in surface water (~14 Bq/L); these comparatively high concentrations are way above the natural background concentration of about 1 Bq/L and result from the release of tritium from the French nuclear power plant Cattenom (situated about 250 km upstream of the sampling site). S-35, produced in the atmosphere and entering the hydrological cycle via precipitation, could be determined only once (January 2021) due to technical obstacles. The S-35 concentration measured in surface water (0.035 Bq/L) was about 4 times higher than the concentration in groundwater (0.0093 Bq/L). Finally, the median δ18O signature in surface water (-8.13 ‰) was similar to the signature found in groundwater (-7.78 ‰).

The selected isotopes and water parameters indicate that (i) the aquifer is predominantly recharged by surface water and (ii) the groundwater mean residence times varies between 5 and 6 months based on S-35 and δ18O.

Hence, it can be concluded that the selected isotopes are suitable as tracers for estimating groundwater mean residence times. However, further studies are needed, especially to minimize the time gap between the established tracers Radon (useful for up to 40 days) and tritium (useful from about one year). The novel tracer S-35 seems promising, but long-term data series of S-35 in surface and precipitation water are still missing to establish the necessary input functions.
Representing Microphysical Uncertainty in Convective-Scale Data Assimilation Using Additive Noise
Authors: Feng Yuxuan , Janjic Tijana , Zeng Yuefei , Seifert Axel , Min Jinzhong
Published: March 2022

For convective clouds and precipitation, model uncertainty in cloud microphysics is considered one of the most significant sources of model error. In our recent paper (Feng et al. 2021), samples for model microphysical uncertainty are obtained by calculating the differences between simulations equipped with two- and one-moment schemes during a one-month training period. The samples are then added to convective-scale ensemble data assimilation as additive noise and combined with large-scale additive noise based on samples from climatological atmospheric background error covariance. Two experiments, including the combination and large-scale error only, are conducted for a one-week convective period. The results reveal that the simulation with a two-moment scheme triggers more convection and has larger ice-phase precipitation particles, which produce a stronger signal in the melting layer. During data assimilation cycling, although more water is introduced to the model, it is shown that the combination performs better for both background and analysis and significantly improves short-term ensemble forecasts of radar reflectivity and hourly precipitation.

Feng, Y., Janjić, T., Zeng, Y., Seifert, A., & Min, J. (2021). Representing microphysical uncertainty in convective-scale data assimilation using additive noise. Journal of Advances in Modeling Earth Systems, 13, e2021MS002606.
Soil organic matter accumulation in vineyards as a function of cultivar and parent material
Authors: Zaccone Claudio , Goldoni Sara Elena , Giannetta Beatrice , Galluzzi Giorgio , Plaza Cesar
Published: March 2022

The aim of this work was to understand of how parent material and plant cultivar interactively control soil organic matter (SOM) accumulation and stabilization in vineyards.

Three experimental vineyards located in the Valpolicella area (North of Italy) were investigated. These sites were very close each other and, consequently, characterized by the same climatic conditions; at the same time, the corresponding soils developed from completely different parent materials (volcanic vs. calcareous). Two autochthonous grapevine (Vitis vinifera L.) cultivars, planted in 2003 and grown in organic system (no fertilization), were selected in all sites, and the corresponding soils sampled in triplicate with a 10-cm depth resolution. An uncultivated soil profile for each site was used as a control.

Soil samples (n. 88) were characterized for pH, EC, bulk density, total organic C (TOC), total N (TN), texture and major and trace elements. Moreover, particulate organic matter (POM) and mineral associated organic matter (MAOM) fractions were isolated and characterized by elemental analysis (CHNS).

Control soils showed different organic C stocks, ranging from 27 in the volcanic soil with a loamy sand texture to 90 t/ha in the two calcareous soils with a clay texture. A similar trend was observed for TN, ranging from 2 in the volcanic soil to 9 t/ha in the calcareous soils. Moreover, 2/3 of TOC were recovered as MAOM in both clay soils, whereas POM was the main fraction in the volcanic, loamy sand soils.

The cultivation of grapevine affected SOM accumulation. In particular, an increase (1.3-1.5×) of both TOC and TN in the top 30 cm of soil was observed in 2 out of 3 sites, while an opposite trend (0.7×) was recorded in one site. Preliminary data suggest that SOM accumulation is promoted in vineyard soils with lower organic C contents (and a wide range of texture) and through different mechanisms, whereas the cultivar factor did not affect TOC and TN stocks.

 

Acknowledgements

CZ thanks the Cantina Valpolicella Negrar for allowing soil sampling in its experimental vineyards.
A Review of Irrigation in the Lower Mekong Basin: Opportunities and Challenges from a Water-Food-Energy Nexus Perspective
Authors: Wang Guanghui , Zhu Tingju
Published: March 2022

Agriculture is essential for economic growth in the Lower Mekong River basin (LMB), which plays a key role in ensuing water and food security of the riparian regions and provides livelihoods for tens of millions of people. Agricultural irrigation, hydropower development, increasing water demand from other sectors, and ecosystem protection necessitate taking a holistic approach when analyzing irrigation in the LMB. This paper examines the existing problems and opportunities of irrigation in the LMB from the angle of water-food-energy (WFE) nexus. We selected journal articles from the Web of Science database and imported them into CiteSpace, a bibliometric analysis software for visual exploration of scientific literature. The visualized results summarize the significance of authors and their affiliations in the selected body of literature, and the country-wise distribution. Four key research themes of LMB irrigation were identified based on the bibliometric analysis, for conducting an in-depth review. First, we investigated the factors that influence agricultural water management which directly affects irrigation water demand and supply as well as crop productivity. This part of the literature focused on water and land management and applications of various models to assess impacts on crop yields of irrigation management. Second, from the literature we analyzed the identified impacts of human flow alternations on downstream water uses, ecosystem health, and land subsidence due to groundwater overdraft. Nevertheless, upstream water management can mitigate downstream flood damages and augment dry-season water supply. Third, the spatiotemporal mismatch between water demand and supply pose a serious challenge for transboundary river basin management. Moreover, inappropriate water utilization, mismanagement and poor governance appear to be the more fundamental causes of the LMB water problems, thus calling for sound agricultural water policies within a riparian country and effective water management cooperation strategies across the riparian countries.  Fourth, despite of the relatively few publications on the Mekong’s WFE nexus so far, this particular topic is gaining growing attention in the Mekong basin research community. Moreover, it offers a valuable holistic perspective for analyzing irrigation in the LMB, by considering its connections with the food and energy sectors in one way or another, compared against many existing studies that view irrigation as solely an agricultural water management problem.
In the context of climate change, how do farmers change their practices or not, why, and with what consequences on water fluxes? Insights from the Rhine Valley (France, Germany, Switzerland)
Authors: Bohnert Gaël , Martin Brice
Published: March 2022

Climate change is posing a threat on agricultural systems, mostly because it modifies the water ressources and dynamics: erosion, floods, drought… Adaptation is therefore becoming a vital issue (Darnhofer et al., 2010). These stakes are particularly high in the Rhine Valley, for agricultural systems are both importantly exposed and vulnerable, due to a significant change in the distribution and intensity of precipitations over the seasons (Riach et al., 2019), and their strong dependancy on a limited number of products (irrigated maize for the intensive crop production and drought sensitive grape varieties like Riesling for wine growing).In order to adapt to climate change, different practices are implemented: reduced soil tillage, soil cover, agroforestry, irrigation, new varieties etc., aiming at fighting against erosion, floods, fungi and/or retaining humidity, and thus modifying the water fluxes in the agroecosystems. In this quite homogeneous geographical area shared between France, Germany and Switzerland, facing the same climatical threats, the adaptation process nevertheless results in a very heterogeneous system, independent of borders. Actually, the choices to implement these practices depend on many factors: farmers’ observations and trials, perceptions of the impacts of climate change, awareness of environmental issues, economical and technical constraints, geolegal frames, and networks, including information exchanges between farmers, communication from agricultural organizations or associations and consumers’ demands. All farmers doesn't have the same goals and are neither equal in the face of the consequences of climate change, nor have the same opportunities to adapt. Moreover, these choices sometimes highlight contradictory objectives and debates, such as in the case of irrigation and glyphosate, and some adaptation measures can have paradoxical consequences on the hydrosystems. In fact, climatic change might lead to increase the gap between two agricultural models, two ways to face to environmental stakes.For this contribution, we based on semi-structured interviews with farmers (crops and wine growing), and we propose to analyze their choices. What adaptation practices do they adopt or not? Why? With which objectives and which consequences on hydrosystems? With wich difficulties and facilitating factors?
Simulating soil loss on farmland hillslope cultivated in centennial periods using magnetic susceptibility in Northeast China
Authors: Yu Yue , Zhang Keli , Liu Liang
Published: March 2022

Soil erosion is a major worldwide threat to agriculture, food security, and ecosystems. Northeast Black Soil Region is an important food base in China and has an important strategic position for ensuring food security. Black Soil Region suffered severe water erosion due to long-term unreasonable utilization. The loss of topsoil in farmland decreases the amount of indispensable fertile soil for plants and reduces land productivity. The magnetic susceptibility (MS) technique has been successfully applied in describing farmland soil redistribution pattern as a reliable, economical, and rapid method, but it still need further study in soil loss quantification. In this study, four typical black soil farmland slopes (cultivated in 110a, 60a, 30a, and 20a) and a reference forest slope were selected, while undisturbed soil samples were collected at a 5 cm interval from the surface to 50 cm depth. The objective is to (1) utilize soil MS values (including χlf and χfd%) and other soil property indexes to represent soil loss on farmland slope; (2) recommend Δχ (the ratio of the difference between MS of the slopes cultivated in two certain periods) as an indicative index of soil loss rate to convert current soil erosion pattern in spatial scale to the certain historical period soil loss in temporal scale; (3) verify the feasibility of MS value in estimating farmland soil loss in multi-temporal scale by cultivation period. The results indicated that: (1) The MS approximately followed the trend of “110 a < 60 a < 20 a <30 a < Forest” at plow layer, that is, the slopes in longer cultivation periods expressed greater MS differences than reference slope; (2) Δχ values were greater at lowerslopes than those at upperslopes and middleslopes, and Δχ at all positions became nearly stable after 50a cultivation; (3) Δχ values were remarkably correlated exponentially with cultivation periods not only on the whole slope but three separated slope positions, with r2 from 0.50 to 0.86. Soil MS reflects soil redistribution and erosion patterns on farmland hillslope. MS values on farmland vary with cultivation periods which denotes soil redistribution. The MS variation caused by tillage was greater at lowerslope than middleslope and upperslope. Soil loss has exponent relation to the cultivation periods. Farmland in longer cultivation periods was associated with greater soil loss, but soil erosion and deposition tend to be stable for slopes in longer cultivation periods. This study demonstrates the feasibility to quantify soil loss in continuous tillage within centennial periods using the MS technique.
Decadal to multidecadal variability in long- and short-lived hydrological extremes in sub-Saharan Africa
Authors: Ekolu Job , Dieppois Bastien , Eden Jonathan , Tramblay Yves , Villarini Gabriele , Mahe Gil , Paturel Jean-Emmanuel , van de Wiel Marco
Published: March 2022

Sub-Saharan Africa is affected by a high-level of temporal and spatial climate variability, with large impacts on water resources, human lives and economies, notably through hydrological extremes, such as floods and droughts. Using a newly reconstructed 65-year daily streamflow dataset of over 600 stations distributed throughout sub-Saharan Africa, we first highlight that the frequency, intensity and duration of hydrological extremes are strongly impacted by decadal to multi-decadal variations. However, the key factors driving such decadal to multi-decadal variability remain poorly documented and understood. To address this research gap, we first compile information on local-scale (precipitation, temperature, soil moisture) and large-scale (e.g., El Niño–Southern Oscillation, Atlantic Multidecadal Variability) drivers. Then, by using relative importance analysis and multiple datasets, we investigate the contribution of large-scale versus regional-scale processes in driving decadal to multi-decadal variability in floods and droughts. Results show that the changes in flood and drought characteristics are significantly linked to modes of climate variability in the Pacific, Indian, and Atlantic Oceans. Although flood and drought characteristics are significantly correlated, the influences of large-scale climate variability on them are non-linear. Meanwhile, local-scale factors impacting floods and droughts are variable throughout the sub-continent. Our results highlight the role that changes in rainfall, soil moisture and temperature play across the major watersheds in sub-Saharan Africa.