bluuebunny/crossref_metadata_2025 huggingface dataset:
On the impact of ocean/wave coupling in tropical cyclones conditions in the Indian Ocean
Authors: Aouf Lotfi , Law-Chune Stephane , Hauser Daniele , Chapron Bertrand
Published: February 2023

Ocean waves play a key role in the exchange of heat and momentum fluxes between the ocean and atmosphere, expecially in extreme wind conditions. The availability of directional wave spectra from SWIM lead to a better description of wave systems nearby the trajectories of tropical cyclones as shown recently by Le Merle et al. 2022. Also the assimilation of these directional observations induced an improved forecast of integrated wave parameters and initial conditions from wind-sea to swell propagation. The objective of this work is to examine the impact of the wave-ocean coupling under cyclonic conditions in the Indian Ocean. Coupled simulations between the MFWAM wave model and the NEMO ocean model have performed over the 2020 and 2021 cyclonic seasons in indian ocean. We used an improved wave forcing by assimilating the directional wave spectra and the corresponding significant wave heights provided by the instrument SWIM of CFOSAT satellite. The impact of this enhanced wave forcing on the ocean circulation was compared with the one without CFOSAT data assimilation. The main coupling processes are wave-modified stress, Stokes drift and wave breaking induced turbulence. The results show that wave/ocean coupling leads to a significant increase of the ocean mixed layer along the trajectories of cyclones. This clearly induces a cooling of the upper ocean layers at the rear of the cyclones. The validation of key ocean parameters indicates an improvement in sea surface temperature compared to satellite data (OSTIA). We investigated the currents variability in the upper ocean following the trajectory of cyclone HEROLD. We also examined the impact of the coupling process driven by the wave breaking induced turbulence and investigated a better parametrization than the used one from Craig and Banner (1992). Further conclusions and comments will be discussed in the final presentation of this work.
Multi-model assessment of the next-decade climate over the Mediterranean region
Authors: Nicoli' Dario , Gualdi Silvio , Athanasiadis Panos , Tsartsali Eirini
Published: February 2023

The Mediterranean region is one of the most sensitive to climate change since it has undergone an intense warming and drying trend during the last decades, dominantly caused by the increase of anthropogenic greenhouse gases’ concentrations. In the context of decision-making processes, there is a growing interest in understanding the near-term climate evolution of this region.
In this study, we explore the climatic fluctuations of the Mediterranean region in the near-term range using two different products: projections and decadal predictions. The former are century-scale climate change simulations initialized from arbitrary model states to which were applied anthropogenic and natural forcings. A major limitation of climate projections is their limited information regarding the current state of the Earth’s climate system. Decadal climate predictions, obtained by constraining the initial conditions of an ensemble of model simulations through a best estimate of the observed climate state, provide a better understanding of the next-decade climate (typically up to 10 years) and thus an invaluable tool in assisting climate adaptation.
Using forecasts from several decadal prediction systems — performed within the CMIP6 Decadal Climate Prediction Project (CMIP6 DCPP) — and the respective ensemble of non-initialized projections, we evaluate future climate changes of the Mediterranean region for some key quantities so as to assess the added value of initialization. Beyond the contribution of external forcings, the role of internal variability is also investigated since part of the detected predictability arises from internal climate variability patterns affecting the Mediterranean by atmospheric teleconnections.
Wind farm wake recovery under different Planetary Boundary Layer schemes in WRF
Authors: García-Santiago Oscar , Badger Jake , Hahmann Andrea N.
Published: February 2023

Currently, to include the effects of wind farms in the Weather Research and Forecasting (WRF) model, a common choice is to use the Fitch wind farm parametrisation (WFP). This WFP has long been implemented into the WRF's standard repository and has been the subject of several wind resource assessment studies. However, one of the disadvantages of its current (WRF version 4.4) set-up is that it is constrained to one Planetary Boundary Layer (PBL) parametrisation. The Fitch scheme is coupled to the Mellor-Yamada Nakanishi Niino (MYNN) PBL parametrisation because it can inject Turbulent Kinetic Energy (TKE) from the turbines into the atmosphere. More importantly, it is the only PBL where the TKE advection can be activated. This feature is essential since it stores the TKE from one time step to the next and prevents the high TKE concentration at the turbine's location.One way for the WFPs to become PBL-independent is to move away from focusing on the TKE source term and parametrise the turbulence in some other way. The Explicit Wake Parametrisation (EWP) is a WFP coupled to WRF that, as opposed to the Fitch scheme, does not include an explicit TKE source term and the turbulence is produced via enhanced vertical shear. The EWP is based on the assumption that the advection and diffusion terms in the RANS Navier-Stokes equations dominate the development of the wake. As a result, the drag equation is also related to the diffusion term from a 1.5 turbulence closure. The EWP then needs the turbine's information, wind speed and the turbulent diffusivity coefficient (Km) from the PBLs to calculate the wind deficit. Given the latter, the EWP can work if Km is present and comes from at least a 1.5-order turbulence closure PBL. However, studies have yet to attempt to prove this feature since it has only been used with the MYNN scheme.In this study, we demonstrate the use of the EWP in WRF when other PBL schemes are used and the implications of this approach. We demonstrate this implementation under ideal neutral conditions with similar setups and forcings (surface roughness length, Coriolis parameter and hub-height wind speed) for two local (1.5-order closure) PBL schemes. Similarly, we test the possibility of coupling EWP into two non-local PBL schemes (first-order closure). The study focuses on the wake recovery behaviour, the drag strength and the power produced by an idealized wind farm under the four PBL schemes. Early results show faster wake recovery from non-local PBls than local ones, which could be related to the diffusivity coefficient values and the PBL's mixing rates.
Consistency of Aerosol Optical Depth from different Aerosol retrieval algorithms and instruments
Authors: Stöffelmair Ulrike , Popp Thomas
Published: February 2023

Aerosols affect climate in several ways. Aerosols together with clouds contribute the largest uncertainties to the Earth’s radiative forcing estimates, according to IPCC. Consequently, accurate retrieval of the Aerosol Optical Depth (AOD) from satellite measurements is important to improve the knowledge about aerosols in the global atmosphere and the associated influence of natural and anthropogenic events on the amount of aerosols. Since the retrieval of AOD is typically under-determined it needs assumptions concerning aerosol properties and the surface of the Earth – consequently, there are several different algorithms. We analyse data from the Copernicus Climate Change Service of retrieved AOD with Dual-View Instruments (Along Track Scanning Radiometer 2 (ATSR2), Advanced Along Track Scanning Radiometer (AATSR), Sea and Land Surface Temperature Radiometer (SLSTR)) and the Infrared Atmospheric Sounding Interferometer (IASI) for the retrieval of Dust AOD.For reliable conclusions the results of these algorithms and of different instruments should be consistent. When looking at different regions we observe, that the consistency between different algorithms differs depending on the type of surface or the geographical location. Looking at fractions of AOD measured by different instruments, we find inconsistencies over deserts and part of the oceans with much sea salt AOD. Apart from that, the results are consistent.Based on these results, we plan to develop a new retrieval ​​combining the different instruments in order to use their respective advantages and to reduce the errors. In a first step data from SLSTR, IASI and additionally GOME-2 will be combined.
Spontaneous groundcover on olive grove management: effects on water infiltration and soil aggregate stability
Authors: González-Canales Javier , Anton Omar , Borrego Adrian , Cuevas Alfredo , Moreno-Delafuente Ana , Ramos Rubén , Sastre Blanca
Published: February 2023

Traditional olive grove management based on frequent tillage promotes erosion and soil structure loss. As a result, soil health decreases driving to degraded and impoverished soils. This problem is worst due to the location of olive groves in slope areas and the climate of central Spain, with long periods of drought and extreme rainfall events, which enhanced the erosion of bare soil. A shift to a more sustainable management model is needed, proposing groundcovers (GC) as an alternative to frequent tillage (TLL), aiming to increase soil organic carbon, protecting and retaining the soil from erosion and increasing nutrient cycling and, at the same time, enhancing other ecosystem services such as carbon sequestration and the increase in soil biodiversity. A trial was carried out in LEÑOSOST project (2018-2021) selecting 16 pairs of olive groves from different farmers in Madrid Region, with a low-density framework of approximately 70 trees·ha-1 (12x12 m spacing). Each plot pair was composed of spontaneous groundcover management and its equivalent with traditional tillage. Soil sampling was carried out at four depths (0-5 cm, 5-10 cm, 10-20 cm and 20-30 cm) for the analysis of specific physical, chemical and microbiological soil properties, such as water-stable aggregates, calculated according to Kemper and Rosenau method (1986) and expressed as the percentage of micro-aggregates wet sieving resistant (< 2 mm diameter). Some soil physical properties were also measured "in situ", such as water infiltration, using a simple ring infiltrometer (Ø=12.5 cm) following the method described in USDA (2001). It has been observed that vegetation cover increases the infiltration rate almost twice in GC plots (109 mm·h-1) than in TLL plots (52mm·h-1), while the percentage of water-stable aggregates under 0-5 cm depth increased the most (49% under GC regarding 38% under TLL plots, p<0.05). Therefore, using groundcovers as olive grove management improves rainwater infiltration, enhancing water storage to be used by the olive tree, and allows the formation of soil aggregates that control soil erosion and host a large number of soil microorganisms thus, improving their functions of decomposition of organic matter and within the nutrient cycling, contributing to improve soil health.
Towards better runoff simulation in the Pamir Mountains
Authors: Huang Jingheng , Pohl Eric
Published: February 2023

Central Asia is a climate change hot spot, facing an unprecedented juxtaposition of regional climate- and water-related issues. Meltwater from the Pamir Mountains plays a crucial role in Central Asia's hydrological cycle, yet there is a little detailed investigation on their response to climate change. Increasing water demand and the assumed ongoing transition from a snow-glacier runoff regime to a volatile rainfall regime in a changing climate demands for a better understanding of the processes governing surface flow in this region. Glacial-hydrological models are key tools for understanding the hydrological response to climate change, informing the planning of possible responses and adaptation. However, modeling is challenging here due to the lack of proper calibration and validation data. Most of the modeling studies in Pamir regions calibrated the model with runoff data only, which is fairly simple but potentially hides internal inconsistencies due to the complexity of feedback mechanisms that govern melt and runoff generation. Further, factors such as model forcing and/or data errors also contribute to simulation uncertainties. There is a clear need for a more detailed investigation of the regional hydrological processes, with systematic calibration and validation methods that allow more robust parameter constraints. This work employed a conceptual distributed hydrological model (SPHY) and tended to unravel the hydrological cycle in a representative catchment in the central Pamir, the Gunt River basin. We tested the usefulness of several state-of-the-art remote sensing, regional climate model, and reanalysis precipitation and temperature data sets in a hydrological application. We found none of them can be equally good in reproducing all targeted hydrological and cryospheric variables (runoff, snow cover fraction, and glacier mass balance). The aims of this study are hence (1) to develop a set of precipitation and temperature correction factors that could improve the model performance, (2) to develop a systematic calibration strategy that could guarantee internal consistency in the simulation of the single hydrological components, and (3) to test whether the corrected forcing data and model calibration strategy can be upscaled to other basins in the Parmir Mountains.
New improvements for monitoring the Ocean Heat Content and the Earth Energy imbalance (MOHeaCAN).
Authors: Marti Florence , Blazquez Alejandro , Meyssignac Benoit , Ablain Michaël , Barnoud Anne , Fraudeau Robin , Rousseau Victor , Chenal Jonathan , Larnicol Gilles , Pfeffer Julia , Restano Marco , Benveniste Jérôme , Dibarboure Gérald , Bignalet-Cazalet Francois
Published: February 2023

The Earth energy imbalance (EEI) at the top of the atmosphere is responsible for the accumulation of energy in the climate system. While necessary to better understand the Earth’s warming climate, measuring the EEI is challenging as it is a globally integrated variable whose variations are small (0.5-1 W.m−2) compared to the amount of energy entering and leaving the climate system (~ 340 W.m-2). Accuracies better than 0.1 W.m−2 are needed to evaluate the temporal variations of the EEI at decadal and longer time-scales. The CERES experiment provides EEI time variations with a typical uncertainty of ± 0.1 W.m−2 and shows a trend in EEI of 0.50 +/- 0.47 W.m−2 per decade over the period 2005-2019.
The combination of space altimetry and space gravimetry measurements provides an estimate of the ocean heat content (OHC) change which is an accurate proxy of EEI (because >90% of the excess of energy stored by the planet in response to the EEI is accumulated in the ocean in the form of heat). 
In Marti et al. (2021), the global OHC was estimated at global scales based on the combination of space altimetry and space gravimetry measurements over 2002-2016. Changes in the EEI were then derived with realistic estimates of its uncertainty.
Here we present the improvements brought to the global OGC and EEI over an extended period (2002-2021), such as the calculation of the expansion efficiency of heat over the total water column, the improvement of ocean mass solution, the empirical correction of the wet tropospheric correction of Jason-3 altimeter measurements (Barnoud et al., 2022).
The space geodetic GOHC-EEI product based on space altimetry and space gravimetry is available on the AVSIO website at https://doi.org/10.24400/527896/a01-2020.003.
 
References:
Barnoud A., Picard B., Meyssignac B., Marti F., Ablain M., Roca R. Reducing the uncertainty in the satellite altimetry estimates of global mean sea level trends using highly stable water vapour climate data records. Submitted to JGR: Oceans.
Marti, F., Blazquez, A., Meyssignac, B., Ablain, M., Barnoud, A., Fraudeau, R., Jugier, R., Chenal, J., Larnicol, G., Pfeffer, J., Restano, M., and Benveniste, J.: Monitoring the ocean heat content change and the Earth energy imbalance from space altimetry and space gravimetry, Earth Syst. Sci. Data, 14, 229–249, https://doi.org/10.5194/essd-14-229-2022, 2022.
Correcting errors in the SPITFIRE fire model that result in excessively large and intense fires
Authors: Oberhagemann Luke , Billing Maik , Drüke Markus , Sakschewski Boris , Thonicke Kirsten
Published: February 2023

The SPITFIRE fire model is used with several Dynamic Global Vegetation Models to model fire-vegetation interactions on a global scale. Since its development in 2010 it has been used for multiple studies in this field. The model consists of components that calculate ignitions, fire spread, post-fire mortality, and emissions. We find that the fire spread component of this model contains errors that introduce significant biases to its results. In particular, errors in the application of the Rothermel equation result in fires that are significantly too large and intense. Further, unphysically low live grass moistures in the model result in excessively fire-prone grasslands, and therefore a strong link between the presence of grasslands and the presence of fire. This combination results in areas where the SPITFIRE model calculates excessive tree mortality and consequent grassland formation. We perform a detailed analysis of these errors and examine the impact that corrections to them have on SPITFIRE model results.
Modeling aviation’s air quality impacts over time in the context of the changing atmospheric composition
Authors: Dedoussi Irene , Quadros Flávio
Published: February 2023

Aviation’s growth has historically outpaced technological and operational improvements to mitigate emissions. Despite the short-term slowdown due to COVID-19, the sector’s growth is forecast to resume in the coming years. Being a unique sector in terms of the altitude that the majority of the emissions are deposited in, aviation contributes to air pollution near and far from airports, in the form of PM2.5, ozone, and NO2, through a series of chemical and physical pathways. Aviation’s growth is heterogeneous globally, with emissions in some regions (e.g., Asia) growing faster than elsewhere (e.g., Europe and North America).Using recent aviation emissions inventories and future forecasts, and the GEOS-Chem global atmospheric chemistry-transport model, we quantify aviation’s global air quality and associated human health impacts in recent years and under different future atmospheric pathways. Both emissions during landing and take-off operations and emissions during cruise are assessed in different regions globally. We isolate the air quality changes attributable purely to the growth of aviation emissions, and those associated with the evolving (background) atmospheric composition which affects the nonlinear pathways between aviation emission and air pollution formation. Given the long timelines associated with the aviation sector, our results highlight the need for the integrated assessment of present-day and future aviation impacts together with those of other evolving sources.
Preventing earthquake instabilities and inducing controlled, slow-slip by active fluid pressure control in the vicinity of a single seismic fault
Authors: Stefanou Ioannis , Tzortzopoulos Georgios , Gutierrez-Oribio Diego
Published: February 2023

We propose a theory for preventing instabilities in frictionally unstable systems such as earthquakes are. We exploit the dependence of friction on fluid pressure and use it as a backdoor for provoking controlled, slow-slip over a single mature seismic fault. We use the mathematical Theory of Control and notions from passivity in order to (a) stabilize and restricting chaos, (b) impose slow frictional dissipation and (c) tune the system toward desirable global asymptotic equilibria of lower energy. Our control approach is robust and does not require exact knowledge of the frictional behavior of the system and its fluid diffusion properties (e.g. permeability, viscosity, compressibility) or of other parameters related to complex physical processes that are hard to determine in practice. We expect our methodology to inspire earthquake mitigation strategies regarding anthropogenic and/or natural seismicity.References[1] Stefanou, I. (2019). Controlling Anthropogenic and Natural Seismicity: Insights From Active Stabilization of the Spring‐Slider Model. Journal of Geophysical Research: Solid Earth, 124(8), 8786–8802. https://doi.org/10.1029/2019JB017847[2] Tzortzopoulos G., Braun P., Stefanou I. (2021), Absorbent Porous Paper Reveals How Earthquakes Could be Mitigated, Geophysical Research Letters 48. https://doi.org/10.1029/2020GL090792.[3] Stefanou, I., Tzortzopoulos, G. (2022). Preventing instabilities and inducing controlled, slow-slip in frictionally unstable systems. Journal of Geophysical Research: Solid Earth. https://doi.org/10.1029/2021JB023410[4] Gutiérrez-Oribio D., Tzortzopoulos G., Stefanou I., Plestan F. (2022). Earthquake Control: An Emerging Application for Robust Control. Theory and Experimental Tests. http://arxiv.org/abs/2203.00296[5] Papachristos, E., Stefanou, I. (2022), Controlling earthquake-like instabilities using artificial intelligence. http://arxiv.org/abs/2104.13180.[6] Gutiérrez-Oribio D., Stefanou I., Plestan F. (2022). Passivity-based Control of a Frictional Underactuated Mechanical System: Application to Earthquake Prevention. https://arxiv.org/abs/2207.0718
Impact of climate change on the water balance of the Thaya basin
Authors: Parajka Juraj , Vizina Adam , Komma Jürgen , Valent Peter , Štepánek Petr , Haslinger Klaus , Schellander-Gorgas Theresa , Viskot Marek , Fischer Milan , Froschauer Walter , Trnka Mirek , Blöschl Günter
Published: February 2023

The Thaya is a trans-national river basin that is situated in the Czech Republic and Austria. Different human activities in the basin and multiple water uses increase the water demand. This increase, combined with the recent droughts events in 2017 and 2018, has recently resulted in reconsidering the water management strategies for future climates. This contribution aims to evaluate the effect of climate change on the water balance of the Thaya. The aim is to apply two different hydrological models in an identical setting (the same model inputs, scenarios, and regional and water use data) and to identify water availability and its change under various climate and water use scenarios. The assessments compare BILAN and TUWmodel hydrological models coupled with the WATERRES water use module and a large sample of climate projections (the CMIP5 and CMIP6 models), which represent various socioeconomic pathways combined with projections of possible changes in water use. The results will demonstrate an insight into how the water balance in different parts of the Thaya basin has changed in the past and what are the possible effects of climate change on these water resources in the future.
Global Budyko water balance assessment application as a diagnostic tool to improve seasonal forecasts
Authors: Modiri Ehsan , Samaniego Luis , Schweppe Robert , Shrestha Pallav Kumar , Rakovec Oldrich , Kelbling Matthias , Martínez-de La Torre Alberto , Sutanudjaja Edwin , Blyth Eleanor , Wanders Niko , Thober Stephan
Published: February 2023

A primary objective of hydrological modelling (HM) is to monitor the water balance in catchments and provide forecasts of key variables and fluxes (i.e., soil moisture and streamflow) at the seasonal scale. Within the Copernicus Climate Change Service, a global seasonal forecasting framework using four state-of-the-art HMs (i.e., HTESSEL, Jules, mHM and PCR-GLOBWB) is developed. The system is required to provide skillful forecasts to provide an added-value to society. In this study, we evaluate the skill of streamflow forecasts using established skill metrics such as Continuous Rank Probability Score and Brier Score.As a first step, we evaluated the performance of the reference run of the four models that is based on ERA5-Land forcing. We employed more than 3100 river flow measurements obtained from the Global Runoff Data Centre (GRDC). These data allow us to classify basins according to aridity and evaporation indices and to evaluate their performance according to geographical regions. In a Budyko analysis, all models adhere to the expected theoretical functions that respect both the conservation of energy and water. However, applying the Budyko analysis to the observational records and reanalysis data only, some basins do not adhere to the energy limit by, for example, having more actual evaporation than potential evaporation. These findings suggest that water may have been transported across basins or that groundwater wells may have been overdrafted. For the development of the global forecasting system, an evaluation of model performance at these basins should be taken with care, and hydrologic models should not be calibrated here. By comparing the regional differentiated Budyko analysis and evaluating the skill metrics of the four HMs, we aim to discriminate among structural and forcing errors. Eventually, this analysis would allow improving the skills of the global seasonal forecasts system.
Estimation of different uncertainties in simulated streamflow from hydrological models
Authors: Akhter Mehnaza , Nayak Munir Ahmad , Ahanger Manzoor Ahmad
Published: February 2023

Streamflow simulated from hydrological models is associated with uncertainty from a variety of sources. The chief sources of uncertainty are: i) errors in the measurement of the observed inputs to the hydrologic models, say precipitation, discharge, and temperature observations, ii) calibration uncertainty associated with algorithms used to estimate the parameters of the model iii) structural uncertainty, associated with incomplete or approximate representation of the catchment with hydrologic models. Operational forecasts generally ignore these uncertainties for important management decisions in water resources, for example, in issuing flood warnings. However, several works have shown that these uncertainties can substantially impact large streamflow forecasts made through hydrologic models. In this work, we explore different error models for estimating the relative contribution of individual error sources to overall uncertainty in the streamflow simulations. Four hydrologic models are used to estimate error distributions at various flow quantiles due to individual sources. The strategy can be adopted to improve the sources contributing to these uncertainties for future predictions from these systems. The approach may be used to reduce the major sources of uncertainty, which will help in reducing the computational efforts in estimating the uncertainties in streamflow simulations.
The role of rift axis faulting in the final stages of magma-rich rifting: the Danakil Depression, Afar
Authors: Hurman Gareth , Keir Derek , Bull Jonathan , McNeill Lisa , Booth Adam , Bastow Ian
Published: February 2023

Traditionally interpretations assume that as magma-rich rift settings mature, the magmatism accommodates greater amounts of extension at the expense of mechanical deformation. However, the importance of faulting in the final stages of magma-rich rifting remains poorly constrained, with the data (e.g. structural geological mapping, seismic reflection and borehole data) from rifts near to break-up a rarity. The Danakil Depression (Northern Afar), is undergoing the final stages of continental break-up, thus providing the ideal natural laboratory to conduct high resolution, quantitative analysis on the architecture, extension and subsidence facilitated by faulting in an active rift setting before seafloor spreading initiates. >500 rift axis faults were identified using remote sensing data (satellite imagery, DEMs), with quantitative analysis showing an increase in fault density, length and connectivity away from magmatic segments. Kinematic and earthquake focal mechanism data demonstrate a transition from transtensional opening in the northern and central sub-regions of the rift to oblique opening in the southern Giulietti Plain and Tat-Ali sub-regions of the Danakil Depression. The oblique opening is attributed to the along-axis step between the Erta-Ale and Harak sub-regions. Integration of seismic reflection and borehole data with the mapped faults shows that extension is primarily accommodated by magmatism within the rift center, with faulting more significant towards the ends of the rift. ~30% of crustal extension is accommodated by axial faulting in areas of low magmatism, highlighting the importance of faulting even in the final stages of magma-rich rifting. Comparing our findings with spreading ridge morphology and structure, which is relevant due to the rift maturity and extensive magmatism present, we conclude that the Danakil Depression is in a transitional stage between continental rifting and seafloor spreading. Spatial changes in the importance of faulting and magmatism in accommodating extension, alongside rift morphology, resemble the relationships observed along spreading ridges. From our observations we have shown that axial faulting still plays a vital role in the final stages of break-up despite the increased importance of magmatism.
Impact of the Mid-Pleistocene Transition on Meuse River Terraces in the Southern Netherlands: New Terrace Burial Ages
Authors: da Silva Guimarães Ewerton , Kasse Cornelis , Busschers Freek S. , Akçar Naki , Roda-Boluda Duna , Schlunegger Fritz , Bouroullec Renaud , Demoulin Alain , Christl Marcus , Vockenhuber Christof , van Balen Ronald T.
Published: February 2023

River terrace deposits are excellent archives of paleoenvironmental conditions. They reflect the tectonic and climatic settings of their time of formation. For this reason, Late-Pleistocene and Holocene terraces have been previously studied in detail because of their good state of preservation and age control. However, less is known about the Middle- and Early-Pleistocene terraces. The Lower Meuse River, a major tributary of the Rhine River, located in the Southern Netherlands, exhibits a well-preserved terrace staircase which, for decades, has been intensely investigated. Age constraints are available, which are mainly based on correlations to the marine isotope record. As of late, the availability of numerical ages of these terraces have been increasing, allowing for a better determination of the boundaries of the Early, Middle and Late Pleistocene terraces.
In order to better understand the effects of the Mid-Pleistocene Transition (MPT; 1.2 – 0.8 Ma) in the Meuse River, we improved the spatial and temporal resolution of the terraces of the Lower Meuse. For the spatial resolution, we used a dense borehole database to characterize key geometrical and compositional parameters of the different terrace levels. For the temporal resolution, we used cosmogenic-nuclide geochronological methods, relying on the measurements of the paired isotopes 26Al-10Be, allowing for the estimation of terraces burial age.
In this work we outline general spatial trends of geometrical and compositional parameters of terraces formed pre-, syn-, and post-MPT. These results are displayed in an improved time framework that relies upon the new burial ages results from the cosmogenic nuclides concentration measured for specific terrace levels. We present three new isochron-burial ages from Main Terrace levels, and thirteen new simple-burial ages from Middle-, Main-, and East Meuse-Terraces.
The results allow us to better understand the signal propagation generated by the MPT. A general increasing trend in the gravel content and terrace thickness have been observed from older to younger terraces. The ages are mostly in good agreement (within uncertainty) with previously proposed age models, especially the ages for the East Meuse Terraces, which have been confirmed to be Early Pleistocene.
Mars regolith simulant as substrate for cultivation of higher plants in Space colonies: the need for organic amendment for potato as a case study
Authors: Paradiso Roberta , Caporale Antonio , Liuzzi Greta , Palladino Mario , De Pascale Stefania , Adamo Paola
Published: February 2023

Future long-term space exploration beyond Low Earth Orbit and long permanence of human colonies on solar system planets will depend on the development of specific technologies able to regenerate resources, while minimizing the waste production, and to exploit the resources available in-situ. Bioregenerative Life Support Systems (BLSSs) are artificial ecosystems in which appropriately selected organisms are assembled by combining their metabolic routes in consecutive steps of recycling, to reconvert the crew wastes (carbon dioxide, faeces and urine) into edible biomass, oxygen and potable water. Higher plants represent an optimal tool to renew air through photosynthesis, to purify water through transpiration, and to recover waste products through mineral nutrition, while providing fresh food and health benefits to the astronauts. However, the configuration of fertile substrates for plant cultivation based on extra-terrestrial resources is still a challenge.Potato (Solanum tuberosum L.) is a candidate crop for space cultivation, based on technical and dietary criteria, including productivity and nutrient composition (content of carbohydrates and proteins). We evaluated the adaptability of potato cv. ‘Colomba’ to the growth on six substrates: the MMS-1 Mars regolith simulant, alone (R100) and in mixture with 30% in vol. of green compost (R70C30), a fluvial sand, alone or mixed with 30% of compost (S100 and S70C30), a red soil from Sicily (RS), and a volcanic soil from Campania (VS). We assessed the physicochemical properties of the substrates, the physiological and biometric parameters, and the nutritional quality of tubers in potato plants grown in pot on in cold glasshouse.Both R100 and S100 were alkaline (pH ≥8.6) and coarse-textured, lacking organic matter and pivotal macronutrients. The amendment with compost significantly lowered their alkaline pH and improved the chemical fertility. The sandy-loam textured VS was sub-alkaline, slightly calcareous, with higher organic C and nutrient availability than RS. This latter was neutral-to-sub-alkaline, clay textured, poorly calcareous, with significantly higher CEC than VS.Leaf photosynthesis was higher in plants grown in terrestrial soils and S100. Plant growth was greater in VS, R70C30 and S70C30, while it was reduced on R100. Plants produced healthy tubers on all the substrates.MMS-1 regolith simulant was found poor in nutrients and unsuitable to sustain adequately the plant growth. Amendment with organic compost improved MMS-1 physiochemical properties and fertility and plant performance.Keywords: Solanum tuberosum L., controlled environment, Bioregenerative Life Support Systems (BLSSs), in situ resource utilization (ISRU), MMS-
Equivalent Biot and Skempton coefficients for fractured rocks
Authors: De Simone Silvia , Darcel Caroline , Kasani Hossein A. , Mas Ivars Diego , Davy Philippe
Published: February 2023

Biot coefficient and Skempton coefficient are key descriptors of the coupled hydro-mechanical (HM) behavior of fluid-saturated porous materials. Biot coefficient defines a relationship between an applied load, fluid pressure and the stress that effectively acts on the solid skeleton. Skempton coefficient defines the temporary pore pressure variation caused by the application of a load in undrained conditions. The product of the two coefficients establishes the impact of an applied load on the solid skeleton, and thus the material deformation, under undrained conditions. The two coefficients are generally estimated through analytical expressions valid for isotropic homogeneous materials, or they are experimentally estimated at the laboratory sample-scale.In this work, we define a framework for the evaluation of equivalent Biot coefficient and Skempton coefficient at the scale of a fractured rock mass. We derive theoretical expressions that estimate the two equivalent coefficients from the properties of both the porous intact rock and the discrete fracture network (DFN), including fractures with different orientation, size, and mechanical properties. These formal expressions are validated against results from fully coupled hydro-mechanical simulations on systems with explicit representation of deformable fractures and rock blocks. We show that the coefficients largely vary with the fracture orientation and density, which implies that disregarding the presence of fractures may incur an incorrect evaluation of the HM response. We also discuss the variability of the coefficients under different settings of DFN properties, including realistic scaling conditions of size-dependent and stress-dependent fracture properties.
The impacts of climate change on the flood risk for Cork city: A case study
Authors: Basu Bidroha , O Sullivan Greene Michael
Published: February 2023

Cork city is considered to be in a vulnerable region to flooding and is expected to face significant economic and social damage due to the effects of climate change in the upcoming future. An increasing trend in the precipitation and temperature coupled with a rise in severity and frequency of storm events leads to a higher frequency of expected flooding for Cork city in the upcoming decades. More floods and severe heatwaves during the summer months will hugely impact Cork’s large agricultural sector and property in the urban, suburban and rural areas surrounding the city. In 2009, Cork city experienced a severe flood event that devastated property resulting in €90 million worth of damages only to the city centre.This study focuses on the identification of the most vulnerable regions in Cork city based on the historically observed flood-related data. Furthermore, the changes in flood vulnerability and risk for the city in the future corresponding to different climate change scenarios have been explored. Three regional climate models (RCMs) and two Representative Concentration Pathways (RCPs) has been considered to obtain future projected meteorological variables, which were used to simulate future projected streamflow using Soil Water Assessment Tool (SWAT) model for each RCM and RCP. The daily simulated streamflow in the future was used to first extract the annual maximum flow, and then to obtain flood quantiles corresponding to different return periods using generalized extreme value distribution. The flood quantiles were then fed into the HEC-RAS model to generate flood inundation maps for Cork city. Comparison of flood inundation maps for a chosen return period for the historical and future period corresponding to different climate change scenarios revealed that the flood depth and flood extend is expected to increase in the future for the majority of the climate change scenarios.A detailed risk assessment based on those developed flood inundation maps were then performed will then be performed for Cork to identify the most vulnerable areas. Subsequently, the social and economic impact of flooding has been quantified in this study. It has been noted that due to climate change, the expected damage from future flood events will ellipse the damage seen in the 2009 flood at Cork city.
Oblique propagation and refraction of mountain waves over the Andes observed by GLORIA and ALIMA during the SouthTRAC campaign
Authors: Krasauskas Lukas , Kaifler Bernd , Rhode Sebastian , Ungermann Joern , Woiwode Wolfgang , Preusse Peter
Published: February 2023

The SouthTRAC measurement campaign was held in Argentina from September to November 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 ALIMA, an upward looking 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. GLORIA is the airborne demonstrator of the satellite based infrared limb imager CAIRT proposed as the Earth Explorer 11 candidate.  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 observed 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.
Oblique GW propagation was directly observed, including propagation of some GWs toward the upwind side of the Andes mountain range. Oblique propagation also resulted in significant meridional transport of zonal gravity wave momentum flux (GWMF).
We observed strong horizontal GW refraction, with some wave vectors turning by more than 50°. This resulted in significant momentum exchange between waves and the background flow outside of wave generation and breaking regions. 
We also use the GLORIA data to study the time dependence (as a result of changing winds) of the mountain wave pattern over the Andes.
The use of optical camera for river turbidity monitoring
Authors: Miglino Domenico , Jomaa Seifeddine , Rode Michael , Isgro Francesco , Saddi Khim Cathleen , Manfreda Salvatore
Published: February 2023

Improving river monitoring techniques is critical given the concomitant impact of climate change, population growth, and pollution over the last years. Turbidity is one of the most significant metrics for water quality characteristics. In river basins, high turbidity values can be indicative of both organic and inorganic materials. Turbidity is often used as a proxy for transport of suspended particles and associated fluxes of hydrophobic pollutants in a wide range of hydrological conditions. However, it is demanding to estimate suspended sediment yields in rivers because of the high variability along stream of suspended sediment concentrations. Traditional methods, such as gravimetric analysis, are time-consuming, expensive, often discontinuous in space and time and influenced by human errors or instrumental limitations.Remote sensing techniques are a suitable alternative to point measurements. Satellite remote sensing allows to study the spatial and temporal variations of water status parameters, but it is limited by the spatial and temporal resolution of the satellites considered. Low range systems can help increase the resolution of the imagery used for this purpose. In particular, the use of optical cameras can significantly reduce the monitoring cost and exponentially increase the information on water bodies health and hydrological dynamics, offering a large amount of data distributed in time and space. Nonetheless, all optical sensing methods are strongly affected by many environmental constraints (light, good optical transmission, visibility, etc.), which make them currently not always suitable for regular long-term monitoring of turbidity in rivers. The main goal of the monitoring procedure identified in this work is to avoid all these constraints, by processing the camera image to use it as a real measurement data. In this work, an image processing procedure has been identified by exploiting the water surface reflectance properties to estimate water turbidity spectral indices related to red and green bands of the light visible spectrum (Miglino et al., 2022). This river monitoring system is under development in different cross sections of the Bode River, one of the best-instrumented catchments in Central Germany.managed by UFZ Helmholtz Centre for Environmental Research. They gather a wide range of environmental data including a long-term time series on water quantity and quality. Preliminary results highlighted interesting similarities between the chromatic variation of the water surface captured by the RGB camera and the real data.  Keywords: turbidity, sediment transport, image processing, spectral indices, remote sensing, camera, water quality assessment. References:Miglino, D., Jomaa, S., Rode, M., Isgro, F., & Manfreda, S. (2022). Monitoring Water Turbidity Using Remote Sensing Techniques. Environmental Sciences Proceedings, 21(1), 63.
Multi-temporal drought rarity curves - a yearly classification of meteorological drought severity in France
Authors: Blanchet Juliette , Ainési Baptiste , Creutin Jean-Dominique
Published: February 2023

Droughts are recurrent phenomena, impacting eco- and socio-systems at varied temporal and spatial scales. Their impact depends on both the severity of the antecedent meteorological conditions and the recovery dynamics of the impacted systems. The drought severity analysis proposed in this study accounts for the ”memory effect” of rainfall accumulation by considering across time the rarity of antecedent precipitation at multi-temporal scales. It applies to rainfall accumulation over a single area. In this presentation, we define the yearly curve of multi-temporal drought rarity by the non exceedance probability of the smallest rainfall accumulations observed that year over a range of accumulation durations. Each rarity curve is thus defined by as many values as the number of durations considered. We apply this concept to droughts in France from 1950 to 2022, with accumulation durations varying from 4 weeks to 260 weeks. We show that the rarity curves are easy tools to summarize how droughts build and persists across time and temporal scales. We use an automatic classification of the curves to discriminate years associated to short- to long-term droughts (basically from half a year to five years). Although the concept is here used for rainfall over a single area, France, it could be applied as well to a set of areas and/or to other drought variables such as discharge or soil moisture. 