bluuebunny/crossref_metadata_2025 huggingface dataset:
Novel methane emission estimation method for ground based remote sensing networks
Authors: Klappenbach Friedrich , Chen Jia , Wenzel Adrian , Dietrich Florian , Forstermeier Andreas , Zhao Xinxu , Jones Taylor , Franklin Jonathan , Wofsy Steven , Frey Matthias , Hase Frank , Hedelius Jacob , Wennberg Paul , Cohen Ronald
Published: March 2022

In order to infer greenhouse gas emissions from a source region, several top-down approaches can confirm or constrain the existing emission inventories.

Due to the long-term stability of methane, the air holds a non-zero background concentration before it enters the domain of interest. This background concentration typically cannot be neglected and poses a major challenge in emission estimates from observations.

Inspired by a Bayesian inversion framework [1] which inverts the background concentrations together with the emissions, we will present a novel (non-Bayesian) inversion framework that estimates the background from the observations and derives the emissions from these calculated enhancements.

Background concentrations are estimated using a combination of measurements at multiple upwind sites, similar to mass balance approaches, but in a more sophisticated manner: The observed total column concentrations at the downwind site are considered to be associated with the concentrations at an upwind site if the backward trajectories calculated by STILT pass close to the respective upwind site. In a second step, the derived enhancements are attributed to the surface fluxes using the STILT calculated footprint.

Methane emission estimates are derived from the total column concentrations measured with six EM27/SUN FTIR spectrometers using ground based direct sunlight spectroscopy. The measurement campaign was carried out in the San Francisco Bay Area in 2016. 

[1] Jones, T. S., Franklin, J. E., Chen, J., Dietrich, F., Hajny, K. D., Paetzold, J. C., Wenzel, A., Gately, C., Gottlieb, E., Parker, H., Dubey, M., Hase, F., Shepson, P. B., Mielke, L. H., and Wofsy, S. C.: Assessing Urban Methane Emissions using Column Observing Portable FTIR Spectrometers and a Novel Bayesian Inversion Framework, Atmos. Chem. Phys. https://doi.org/10.5194/acp-21-13131-2021, 2021.
Deglaciation dynamics of the Rio Cisnes palaeo-outlet glacier (~45°S), former Patagonian Ice Sheet
Authors: Cooper Emma , Thorndycraft Varyl , Davies Bethan , Palmer Adrian , García Juan-Luis
Published: March 2022

The former Patagonian Ice Sheet (PIS) expanded and contracted multiple times during the Quaternary, preserving a well-defined geomorphological and sedimentological record of ice extent and dynamics. Influenced by both regional (e.g. Southern Westerly Winds) and interhemispheric climate forcing mechanisms, reconstructions of PIS extent and dynamics through time may yield unique insights into Southern Hemisphere (palaeo-)climate and (palaeo-)glacier dynamics.

An increasing number of palaeoglaciological reconstructions in Patagonia have highlighted spatial asynchrony in the timing of local glacial maxima and deglaciation. This offset in the timing of ice advance/retreat implies that dynamic controls, such as topography or calving mechanisms, played a part in regulating the structure and pace of deglaciation. Assessing the role of these mechanisms is complicated by a general lack of glacial landsystems work in Patagonia, particularly north of the Northern Patagonian Icefield (46 – 47.5 °S).

Here we aim to understand the timing, structure, and style of deglaciation in the Rio Cisnes valley, an eastern outlet glacier of the former Patagonian Ice Sheet. We combine glacial geomorphological mapping, field sedimentology, Uncrewed Aerial Vehicle (UAV) photogrammetry, and a new chronology based on cosmogenic nuclide surface-exposure age dating. These data informed a refined deglacial ice and palaeolake reconstruction. The new 10Be exposure ages constrain the timing of palaeolake level drop to ~16 ka, which indicates that icefield outlet glaciers were retreating back from their zone of confluence in the Cisnes valley into their respective valleys by this time, leaving the main Cisnes valley ice free.
Relaxing ETAS’s Assumptions to Better Capture the Real Behavior of Seismicity
Authors: Mizrahi Leila , Nandan Shyam , Savran William , Wiemer Stefan , Ben-Zion Yehuda
Published: March 2022

When developing next-generation earthquake forecasting models, the key is to more carefully account for the real world (which has fault systems with different properties, site-specific properties, swarm-like episodes of temporally elevated seismicity, etc.), without constructing overly complicated models that are hard to comprehend and even harder to use. Finding the sweet spot between simplicity and accuracy is what constitutes the art of modelling. Epidemic-Type Aftershock Sequence (ETAS) models, despite being introduced over three decades ago, are still the undisputed reference for earthquake forecasting methods – be it as a benchmark when testing novel forecasting techniques, or as the model of choice for operational earthquake forecasting around the world. ETAS models accurately describe the average behavior of aftershock triggering as a self-exciting point process based on few simple empirical principles, including the Omori-Utsu and Gutenberg-Richter laws.

With this in mind, we are proposing a new model which naturally captures the diversity of conditions under which earthquakes take place. Within the ETAS statistical framework, we relax the assumptions of parametrically defined aftershock productivity and background earthquake rates. Instead, both productivity and background rates are calibrated with data such that their variability is optimally represented by the model. This allows for an impartial view on the behavior of background and triggered seismicity in different regions, different time periods, or different sequences. We perform pseudo-prospective forecasting experiments for Southern California to evaluate models based on their accuracy at forecasting the next event. These experiments reveal when, where, and under which conditions our proposed model yields better forecasts than the standard ETAS null model. 
How realistic are the spatial patterns simulated from field-scale resolving land surface models?
Authors: Chaney Nathaniel , Torres Rojas Laura , Cai Jiaxuan , Vergopolan Noemi
Published: March 2022

Emerging field-scale resolving land surface models (LSMs), such as HydroBlocks, aim to model the water, energy, and biogeochemical cycles (e.g., surface energy partitioning) at 10-100 meter spatial scales over continental extents. However, there has yet to be a concerted effort to evaluate the realism of the simulated field-scale spatial patterns. This presentation challenges the scientific community to evaluate the modeled multi-scale spatial patterns of contemporary land surface models more critically. Here, we present an approach to evaluate the modeled multi-scale spatial patterns of land surface temperature (a linchpin state variable in the land surface energy and water cycles) of the HydroBlocks LSM using GOES-16 land surface temperature over the contiguous United States (CONUS).

To perform this evaluation, HydroBlocks is run at an effective 30-meter spatial resolution over CONUS at an hourly time step between 2015 and 2020. The domain is then split into 0.5 arcdegree grid cells (~50 km) and a series of spatial statistics are computed (e.g., spatial variance and correlation length) at hourly, daily, monthly, and annual time steps. These spatial statistics are also calculated using the GOES-16 land surface temperature product at the available time steps (with 80%+ spatial coverage per 0.5 degree grid cell). GOES-16 provides hourly observations of land surface temperature over CONUS at a 2 km spatial resolution. The simulated and observed spatial statistics are then compared between 2017 and 2020 for each macroscale grid cell over CONUS. The results show a poor correlation between the two at hourly time scales but show marked improvement over larger time scales. In any case, the surprisingly weak correlation between the observed and simulated spatial statistics reinforce the need to think more critically about the spatial uncertainty chain in land surface models. More importantly, this work reemphasizes the need to make simulated spatial patterns an integral part of the evaluation and calibration of macroscale land surface and hydrologic models moving forward.
The warmer the better?: the relationship between ecosystem metabolism and temperature, possible implications under climate change – a meta-analysis
Authors: Reyes Aldana Hugo Enrique , Graber Daniel , Weitere Markus , Cohen Matthew , Risse-Buhl Ute
Published: March 2022

River and stream metabolism have been proposed as an important tool to determine ecological status, as it encompasses most of the environmental interactions. However, some of the factors influencing it have not been studied with enough depth, which is essential to define its utility as a monitoring and diagnostic tool, especially under the variable conditions of the current global changes. One of these understudied factors is temperature, which may become problematic considering the increasing temperatures and heatwaves occasioned by climate change. For instance, increasing temperatures due to climate change or extreme events may favor the proliferation of algal species resistant to high-temperature variability occasioning blooms and altering ecosystem metabolism. Thus, there is a need to understand how temperature affects ecosystem metabolism and its components, to be able to propose better and more integrative measures to counteract negative changes and make predictions of possible scenarios. This work presents a meta-analysis of the current information that is available on the response of ecosystem metabolism to temperature and highlights some of its implications and perspectives. With this information, scientists, managers, and stakeholders might be able to have a wider perspective and propose more adequate measurements in terms of ecosystem metabolism and ecological status.
Sensitivity analysis of network structure in missing streamflow data complementation using Bidirectional Short-Term Memory network
Authors: Nagasato Takeyoshi , Ishida Kei , Sakaguchi Daiju , Amagasaki Motoki , Kiyama Masato
Published: March 2022

Streamflow data based on the observation may be partially missing due to flood or malfunction of the measuring equipment. Here, it is important to complement the missing flow rate with high accuracy for water resource management and flood risk management. Various statistical approaches such as linear regression and multiple regression models have been proposed as methods for complementing missing flow rates. Among the statistical methods, deep learning has been rapidly evolved with the improvement of computational equipment. Then, deep learning methods have achieved remarkable success in various fields. It may indicate that there is a possibility that the missing flow rate can be complemented with high accuracy by using the deep learning method. Therefore, this study implemented deep learning for missing streamflow complementation. In addition, because the network structure of deep learning may have a great influence on estimation accuracy, this study conducted a sensitivity analysis of the network structure. Among the deep learning methods, Bidirectional LSTM (Bi-LSTM) was implemented in this study. Bi-LSTM is a kind of LSTM that can learn long-term dependence of time series data. Bi-LSTM learns data in both forward and backward directions, compared to Unidirectional LSTM which learns data forward directions. As for the input data, both hourly streamflow and precipitation data were used. For model learning and evaluation, missing streamflow data were artificially generated. The results show that Bi-LSTM can complement the flow rate with high accuracy. It also showed the importance of optimizing the network structure.
A Monte-Carlo-type simulation for exploring the initiation of motion criteria for boulder transport by storm waves
Authors: Weiss Robert , Cox Ronadh
Published: March 2022

The ability of storm waves to move very large boulders (tonnes to hundreds of tonnes) has been documented in recent years.  However, the dynamics of wave-boulder interactions, and the criteria for initiation of transport, are still very poorly understood.  Here, we apply a Monte-Carlo-type model for boulder dislodgement. To account for uncertainties about both the hydrodynamic characteristics at the time of dislodgement and the pre-transport topographic setting of the boulders, the model treats various parameters (e.g. drag and lift coefficients, roughness,, and slope) as random variables . This allows us to test a full range of possible conditions and determine initiation of motion criteria. This Monte-Carlo type model acknowledges the fact that we can observe the result of boulder transport, while the initiation of boulder transport is pivotal to understand the hydrodynamic forces that cause transport.

The input dataset consists of 1,153 boulders that were transported by storms during the winter of 2013-2014 in western Ireland (Cox et al. 2018) The boulders range in mass from <1 tonne to 620 tonnes, and were observed to move at a range of elevations (0-26 m above sea level) and at up to 220 m inland. We know the dimensions, masses, and post-transport locations of all boulders, and we know the season in which they moved, but we do not know the specific wave events that transported them. Therefore. we simulate dislodgement for each boulder20,000 times, with drag and lift coefficients and roughness set by the algorithm as random variables, which allows us to identify the flow conditions that result in dislodgement for each individual boulder mass. In total, we simulate a Monte-Carlo set of 20,000 realizations for each of the 1,153 boulders in the dataset.

From the dataset generated, we characterize populations with various characteristics(such as mass, location, distance to the shoreline), and we compare the simulated flow velocities required for transport with hindcast wave conditions for the storm events during the 2013-2014 season when the boulders underwent transport.

This large field-measured boulder dataset, in combination with the Monte-Carlo-type boulder dislodgement model, provides a unique opportunity to link actual boulder-derived flow conditions required for initiation of motion, to the offshore or nearshore characteristics of the causative events. This is not only important for benchmarking how well boulder dislodgement models can capture the magnitude of storms, but can also potentially be used in situations where we do not have direct observations, to shed light on the question of whether tsunami or storms are the causative events for boulder movement.
Snow drought reduces water transit times in headwater streams
Authors: Segura Catalina
Published: March 2022

Knowledge of water transit times through watersheds is fundamental to understand hydrological and biogeochemical processes. However, its prediction is still elusive, particularly in mountainous terrain where physiography and precipitation change over short distances. In addition, much remains to be studied about the impact of climate change on transit time as it continues to change precipitation form in mountainous terrain. Water isotopic ratios were used to evaluate mean transit time (MTT) and young water fractions ( ) in seven small mountainous watersheds in western Oregon over the 2014–2018 period that included a major regional snow drought in 2015. The MTT was shorter in 2015 across all watersheds compared to any other year while the  was larger in 2015 than in any other year. The short transit times observed in 2015 could be related to low connectivity between surface water and older ground water which resulted in a homogenous hydrologic response across all the investigated watersheds despite their physiographical differences. The 2016–2018 MTT vary widely across all watersheds but especially within the smaller high elevation watersheds indicating that the impact of the 2015 snow drought was stronger for systems that depend heavily on snowmelt inputs. During relatively wet/cold years intrinsic watershed characteristics such as drainage area and terrain roughness explained some of the variability in transit time metrics across all watersheds. Shorter transit times during the drought have implications for water quality and solute concentrations as biogeochemical processes are controlled in part by the time water resides and interacts within the subsurface. Although the impact of the 2015 snow drought appears short lived these results are particularly critical considering the expected regional snowpack decline as the climate warms in the western USA.
Modelling the irrigation water demand through integration of irrigation scheme with NASA-Land Information System Framework (LISF)  in India
Authors: Gupta Manika , Srivastava Prashant K , Arsenault Kristi R , Sahai Atul K
Published: March 2022

The current study provides the irrigation water estimate based on incorporation of satellite-derived irrigation scheme and crop datasets into the NASA-Land Information System Framework (LISF) in India. NOAH 3.3 land surface model within NASA-LISF was run at 0.05-degree resolution for nine years from 2011 to 2019. The irrigation scheme accurately captures the seasonality and the two growing seasons that is December-March and August-November. The MODIS leaf area index product helps to regulate the seasonality and estimated irrigation amount and timing is based on 50% depletion of soil moisture at the field capacity in the rootzone. The results show that the evapotranspiration (ET) and latent heat flux (LE) have increased significantly in the cropped region with improvement in correlation with the MODIS ET and LE products. The study also shows an improvement in soil moisture simulation at the test sites (Varanasi and Gujarat). Besides, successfully demonstrating the irrigation timing and quantity, the present study can also be relevant to hydrological and energy fluxes studies of areas that still lack proper quantification of agricultural practices utilizing irrigation.
Large Sample, High Dimension Hydrology Dataset Validation: Getting Bit By Bytes
Authors: Kovacek Daniel , Eugeni Sophia , Weijs Steven
Published: March 2022

Many large hydrometeorological datasets have been developed and published in recent years in support of wide applications from physical to machine learning models, and from operations forecasting to prediction in ungauged basins.  The HYSETS database (Arsenault et al. 2019) is one such large-sample dataset featuring numerous physiographic, geologic, and climate attributes associated with over fourteen thousand monitored watersheds in North America and Mexico.  The wide array of geospatial data sources used to extract the many basin attributes described by this dataset, combined with the continental scale of study regions, necessitates the assembly of geospatial data sources with non-uniform properties and the analysis of observations collected by different governing organizations.

In this study, the static basin attribute set derived for the HYSETS database was replicated.  Preliminary results suggest that incorporating updated geospatial data sources such as higher resolution DEM, and the interpretation of basin attribute derivations due to the use of different software packages, can yield distinct estimates of statistical properties of basin attributes with implications for their use as model input data.  At the very least, the preliminary results demonstrate that the greater the size and complexity of a dataset, the greater the likelihood of introducing bias and computational error.
Understanding hydrocarbon fate and transport in peat soils using column experiments
Authors: Gupta Pankaj Kumar , Gharedaghloo Behrad , Price Jonathan S.
Published: March 2022

Increasing hydrocarbon resource developments in and around peatlands impose risks of petroleum hydrocarbon spills on these important wetland landscapes. Despite the potential severity of consequences, there is a big gap of knowledge on parameter values controlling liquid hydrocarbons’ redistributions in peat soil after a spill. Complete excavation of contaminated peat soil is a common practice in contaminated sites, but destroys wetland function, and contributes nothing to the understanding of the problem. To partially fill this knowledge gap and to examine potential remediation strategies that are less destructive, we examined the fate, transport, and degradation of petroleum hydrocarbon non-aqueous phase liquids (NAPLs) in peat soils using a series of column tests on intact peat monoliths. Three-phase flow experiments with numerical simulations provided values of multiphase flow parameters that control NAPL redistribution in a variety of peat soils. We observed that water table fluctuations reduced residual NAPL saturation from 8.1-11.3% to 7.7-9.5%; increased headspace concentrations of n-C8 and n-C12 an average 163.7% and 13.4%, due to volatilization. Results also illustrated that water table dynamics promoted growth (from 104 CFU/gram to 106 CFU/gram peat) of specialized microbial communities in NAPL polluted peat columns. These results suggest that water table fluctuation can be a suitable tool for physical and microbial NAPL removal in peat soils, and for the first time provide evidence for it. We also observed a high ratio of Proteobacteria to Acidobacteria in the NAPL contaminated zone, which can be linked to the restoration success for a NAPL polluted peatland. The results could help environmental scientists in forecasting the behavior of spilled non-aqueous phase liquids (NAPLs) in peatland.
Age and geochemistry of the Kamthai carbonatites, Rajasthan, western India
Authors: Mahala Milan Kumar , Ray Jyotiranjan S.
Published: March 2022

The Kamthai carbonatites form part of the Sarnu-Dandali alkaline complex (SDAC) of Rajasthan, western India. The SDAC is one of several alkaline intrusive complexes emplaced prior to the Deccan continental flood basalt eruptions. Considered as one of the earliest Deccan-Reunion plume related magmatic activities, the rocks of the complex hold clues to many tectonomagmatic processes such as plume-lithosphere interaction, mantle melting prior to flood basalt volcanism, and carbonatite-plume relationship, apart from the outstanding questions pertaining to the origin of carbonatites themselves, and their association with alkaline silicate rocks. To understand some of these processes vis-à-vis the evolution of the complex, we have carried out a detailed field, petrographic, geochronological (40Ar/39Ar), geochemical, and Sr-Nd-Pb-C-O isotopic investigation. Phlogopites from carbonatites yield an age of 68.6 Ma, identical to the ages determined for the three associated phonolite dykes. Interestingly, an earlier study reports the presence of older (89-86 Ma) subvolcanic and volcanic bodies in the complex, thus suggesting recurrent alkaline magmatism. Carbonatites of Kamthai occur as veins, dykes, and small plugs, along with dykes/plugs of ijolite, nephelinite, syenite and phonolite etc. The SDAC intrudes into the basement made up of Malani Rhyolites. The stable C-O isotopic compositions of unaltered carbonatites (δ13CPDB= -6.6 to -4.6 ‰; δ18OSMOW=5.5 to 9.5 ‰), which are predominantly calcite carbonatites, not only confirm the magmatic nature of the rocks but also show evidence of fractional crystallization. The chondrite-normalized rare-earth element patterns of the carbonatites and alkaline silicate rocks show LREE enriched patterns, with the former possessing abnormally high contents of LREE. The average (87Sr/86Sr)i and εNd(t=68.5 Ma) for carbonatites are 0.7043±0.0001 and 2.4±0.2, respectively, which are indistinguishable from those for the alkaline silicate rocks (87Sr/86Sr)i= 0.7045±0.0003; εNd(t)=2.4±0.4), which suggests common parentage. All these data point towards a petrogenetic link between the 68.6 Ma carbonatites and alkaline silicate rocks of the SDAC, either through liquid immiscibility or fractional crystallization of a common parental magma. Overlapping initial Sr-Nd isotopic ratios of these rocks with those of the least contaminated Deccan lava flows and the Reunion island rocks suggest a possible genetic link between the SDAC and the Deccan-Reunion plume. 
Tailings dam monitoring and early warning with InSAR technique
Authors: Svendsen Ida , Piciullo Luca , Vöge Malte , Montalti Roberto , Intrieri Emanuele
Published: March 2022

Waste materials produced by mining activities (tailings) can be collected in artificial ponds delimited by earth embankments (tailings dams). In case of tailings dam failure, the consequences are often catastrophic for the surrounding communities and livelihoods as this rupture may release large amounts of tailings and mining wastewater that moves downstream. Furthermore, the mining by-products cause, in many cases, a devastating impact on the surrounding environments and ecosystem. As an increased trend of tailings dam failure has been observed in the last decade, there is an urgent demand from the industry as well as the civil society and the investor community to gain a broader understanding of the risks posed by tailings facilities. Furthermore, efficient techniques to monitor and predict the failure of tailings dams are also crucial.
 
This study investigates how the satellite remote sensing interferometric synthetic aperture radar (InSAR) technique can be used to monitor tailings dams and the applicability of the inverse velocity method to predict failures. InSAR data have been used to map surface displacement prior to dam failures in two case studies: the Feijao tailings dam in Brazil and the Cadia tailings dam in Australia. In the case of the Feijao dam, both the SBAS and PS techniques were applied to process displacement time-series from the satellite data. For the Cadia dam, data processing was carried out using the SqueeSAR algorithm.

The inverse velocity method uses surface displacement measurement points to predict a time of failure. For the Feijao dam InSAR dataset, the inverse velocity method was applicable to different periods presenting an evident increase in the displacement rate. However, it was difficult to retrieve any reliable indication of failure. Contrary to the Feijao dam, the results from the Cadia dam shows a significantly accelerating deformation with time, and by applying the inverse velocity method a predicted time of failure can be retrieved in good agreement with the actual failure.  
On the age and expression of extreme Sarmatian hydrological changes of the Eastern Paratethys in the Caspian Basin (Late Miocene, Kazakhstan).
Authors: Lazarev Sergei , Krijgsman Wout , Vasilyan Davit
Published: March 2022

The Eastern Paratethys is a former epicontinental sea that in the Late Miocene was spread over the vast areas of Eastern Europe and Central Asia. Combining three major subbasins – The Dacian (Carpathian foreland), the Euxinian (Black Sea) and the Caspian basins, the Eastern Paratethys played a vital role in the regional climate, paleobiogeography and ecosystem sustainability. At around 11.6 Ma the Eastern Paratethys became hydrologically isolated from the global ocean due to the tectonic closure of its gateways. For the next 5.5 Ma (up until 6.1 Ma), the Eastern Paratethys turned into a megalake that was trapped in the Eurasian interior. Warming and drying of the climate during so-called Sarmatian Stage (12.65-7.65 Ma) disbalanced precipitation/evaporation ratio in the megalake and thus provoking extreme water-level fluctuation of several hundred meters. Subsequent changes in the water chemistry and temperatures drove the regional ecosystems to the edge of extinction.

The paleoenvironmental evolution of the Eastern Paratethys has been mainly inferred from geological record of the Black Sea and partly Dacian Basin. At the same time, reconstruction and dating of Sarmatian hydrological and faunal changes for the Caspian region remains uncomprehended.

Here, we present our new magnetostratigraphic data on Sarmatian record from the Caspian region (Karagiya Depression, Kazakhstan) and compare it with the data from the other Eastern Paratethys subbasins (the Dacian and Euxinian Basins). Sedimentological observations together with magnetostratigraphic constraints indicate incompleteness of the lower (Volynian) and upper Sarmatian (Khersonian) deposits in the studied section. The middle (Bessarabian) and upper Sarmatian (Khersonian) s.l. begin as transgression events within reversed zones preliminary correlated to C5r.2r (11.188 – 11.592 Ma) and to C4Ar.2r (9.426 - 9.647 Ma) respectively. Sarmatian deposits are transgressively overlain by Maeotian deposits with the boundary occurring within a small reversed chron preliminary correlated to C3Br.3r (7.499 – 7.537 Ma).

The newly acquired polarity patterns suggest that the major Sarmatian paleohydrological events in the Caspian segment were coherent with the other parts of the Eastern Paratethys. However, the complexity of polarity patterns and highly condensed character of the section require further refinement of magnetostratigraphic age constraints.

 
How litter feeding arthropods can promote carbon sequestration
Authors: Frouz Jan
Published: March 2022

Soil fauna can support soil organic matter storage. Important mechanisms facilitation this effect is connected with bioturbation and mixing of organic matter with clay particles which can stimulate accumulation of microbial necromass on mineral surfaces as shown in earthworms. However it has been show that also litter feeding fauna which do not ingest mineral soil may slow down organic matter decomposition and support carbon storage. In this contribution we bring overview of potential mechanisms that may be responsible for this phenomena. Decreased decomposition rate in fauna excrements might result from the removal of easily available polysaccharides, the increase in aliphatic components, an increase in the resistant components of lignin, the accumulation of microbial cell walls (microbial necromass) by increasing of microbial turnover, by binding of nitrogen into complexes with aromatic components, which reduce N availability an finally by higher availability of nitrogen in leachate coming from fauna excrements which may cause negative priming effect and slow down decomposition. These mechanisms will be illustrated on examples and their implication of carbon sequestration will be discussed.
Groundwater born Fe(II) affects concentrations of  dissolved O2 in stream water
Authors: Parra-Suarez Silvia , Wild Romy , Barth Johannes Barth , Gilfedder Benjamin S. , Geist Juergen Geist , Dichner Silvia , Peiffer Stefan Peifer
Published: March 2022

The interface between groundwater and surface water is a critical zone that influences ecohydrological and biogeochemical cycles within the surface water ecosystems. It is characterized by complex redox gradients. with groundwater-mediated inflow of reduced substances into the stream water. 
In this study, we have experimentally simulated the inflow of Fe(II)-rich groundwater with concentratrion of up to 1000 mmol L-1  into the open stream water of a flume system in order to quantify its effect on dissolved oxygen concentration in both the stream water and the hyporheic zone. The experimental setup consisted of 24 flumes, 12 of which were used for input of groundwater augumented with Fe(II), while the another 12 were used as controls, i. e., with inflow of Fe(II)-free groundwater. In addition, the experimental set-up provided the possibility to study the effects of fine sediment (coarse reference substratum (5% fine sediment content) vs. added fine sediment (35% fine sediment content) and low discharge (reference flow conditions vs. low discharge (drought) conditions within a threefold replicated, crossed design. All flumes had permanent groundwater input during the experiment. Fortnightly sampling campaigns were performed to analyze Fe(II), Fe(III),  and DO, concentrations in the porewater (hyporheic zone) and the open water over five consecutive weeks. 
Our results clearly indicate that Fe(II) inflow resulted in a decrease of DO concentrations both in the porewater and subsequently in the open water, with distinct effects of sediment porosity and discharge. Over the five weeks, the sustained decrease between 40 and 50% of DO concentrations was more pronounced in flumes with fine sediment than in flumes with coarse sediments. Our findings suggest that increasing the Fe(II) concentration in the hyporheic zone can affect the availability of oxygen, important in controlling biogeochemical and ecological processes, microbial activities, and aquatic life. The formation of oxygen-depleted subsurface and surface waters in freshwater ecosystems has been associated with nutrient-rich waters stimulating eutrophication and the subsequent reduction of river health. In conclusion, this study highlights the importance of considering the effects of hyporheic redox processes and Fe(II) in assessing the health of stream ecosystems.  
Controlled floodbasins: driving land-level rise along estuaries
Authors: Weisscher Steven , Baar Anne , Kleinhans Maarten
Published: March 2022

Dikes are the conventional means of flood defence along rivers and estuaries. However, dikes gradually lead to the superelevation of waterbodies, and the common method of enforcing dikes is unsustainable as this is expensive, contends with limited space for urbanisation and may aggravate ecological deterioration. Therefore, future flood management requires new, sustainable strategies that not only minimise flood risk, but also steer land-level rise and improve ecology. An example is controlled floodbasins, where a part of land is temporarily opened to the tide to capture sediment and rise well above mean sea-level. This study explores how the sequence of opening controlled floodbasins affects sediment capture and large-scale estuary dynamics through 2D modelling in Delft3D. To this end, different floodbasin configurations and delays of opening floodbasins were tested along the Western Scheldt Estuary (NL). Findings show land-level rise in all configurations. However, opening more floodbasins results in a lag of muddy sediment capture in floodbasins opened later in a sequence, most likely due to a deficit of fines. Opening of the more landward located floodbasins generally leads to a stronger reduction in tidal range if opened alone or at the start of an opening sequence compared to more seaward located floodbasins. Also, the floodbasins seem to result in stronger erosion and deposition patterns in the estuary seaward of the floodbasin inlets, but it is still unclear whether and how this trend influences the channel migration rate. The results imply that a well-chosen location and timing of opening floodbasins, which may vary for different estuaries, can have a positive impact on reducing flood risk.
Joining Geo Data Across Different Providers to Ease Machine Learning Applications
Authors: Rieke Matthes , Gräler Benedikt , Jirka Simon
Published: March 2022

Data integration and harmonization has been a tedious task ever since. The increase of available data in volume and variety has further increased the need for a thorough data integration. Furthermore, the application of more and more automatic algorithms stresses the need for a sensible geo data platform to avoid the ‘garbage in, garbage out’ trap and to allow for a meaningful data analysis. We reviewed different projects and learned about various needs and constraints of joint spatial research data infrastructures from local to cloud based deployments. Typically, these systems are not designed from scratch and existing systems need to be integrated or interfaced. As a result or arising from the need to support the sovereignty of distributed data centers, modern infrastructures need to be capable to support federated set-ups. Often these research data infrastructures shall not only be used to store raw data for scientists, but will also provide results (maps, derived data products, tools and applications) to the public. This goes along with the need for access delegation (e.g. OAuth). A special focus is put on the provision of the joint datasets for machine learning applications. In order to facilitate efficient learning and prediction a ML processing environment needs to be aligned with the data infrastructure. 

We will present commonalities among these infrastructures and outline typical design patterns. A spatial data infrastructure based on open source software components that can be deployed on the cloud will be introduced. It features open standardized interfaces and services for easy adaptation and connectivity.
Early reaction of plagioclase : an underrated alteration step during burial of the continental crust
Authors: Labrousse Loic , Baisset Marie , Schubnel Alexandre
Published: March 2022

Mutual links between metamorphic reactions and rheological properties of rocks under pressure, temperature and deviatoric stress are a major source of discrepancy of thermo-mechanical models when it comes to predict strain localization for instance. The interactions between metamorphism and strain are also considered as a possible cause for unexpected mechanical instabilities, e.g. mechanical failure, in lithological units buried deep in convergent plate boundaries.

The partially transformed granulite facies anorthosites on the Holsnøy Island, Bergen Arcs, Norwegian Caledonides, constitute one of the few archetypical exposure of crustal rocks deforming and reacting at the same time in the eclogite facies conditions. In these rocks, eclogite-facies paragenesis develops with devitrification patterns in « brittle » pseudotachylyte, and in their damage walls, along a pervasive network of « ductile » shear zones, as well as « statically » along digitations following the preserved granulite facies foliation, with no apparent relation to strain.

The present study, that follows recent advances in the understanding of relationships between crystallization of pyroxene and local scale pressure field, or modeling of the interaction between the eclogitization reactions sequence and strain localization, focuses on the first steps of incipient plagioclase destabilization along eclogite facies « fingers ». 

Granulite facies plagioclase, close to 40 % anorthite in composition, is subject to reactions both in the NASH and CASH subsystems, with contrasted stoechiometries and kinetics. Petrological observations evidence that the lowermost pressure reaction in the CASH system (an + H2O = zo + ky + qz), occurs unbalanced, with high kinetics and reaction volume change and therefore initiates strain within plagioclase grains, that react by twinning and subgrains individualization. This early stage of intra-grain transformation induces an effective grain size reduction, and favors fluid percolation, therefore promoting the eclogitization progression. The reaction occurring inside of plagioclase grains also affects their grain boundaries where kyanite and transient reactions products, such as potential melts, accumulate also altering the overall aggregate properties. 

We claim that this early, fast and pervasive reaction is a significative, yet underrated, step of mechanical alteration of the burying continental rocks.
Visualization and quantification of single and multiphase flow in a rough fracture
Authors: Wang Ping , Huang Yong , Guadagnini Alberto , Zhao Xiang
Published: March 2022

Immiscible displacement of fluids across fractures with spatially variable aperture is key in several subsurface processes, including enhanced oil recovery and geological CO2 sequestration. We illustrate the results of an experimental investigation campaign focused on qualitative and quantitative assessment of main features associated with single and multiphase flow in a single fracture, including, e.g., an appraisal of the geometrical parameters of the fracture and the distribution and dynamic characteristics of fluids.
Experiments are performed on fracture replicas reproduced from natural rock blocks, that are artificially split by steer wedges under normal load. Two fracture replicas are then considered, corresponding to (a) a sample molded with synthetic material after the rock sample and (b) the actual rock sample, respectively. This enables one to provide a first appraisal of the impact of the material constituting the wall of the fracture on the multiphase flow system behavior. A transparent upper wall is set in place to enable visualization.
Surface profiles of the fracture are collected, comprising a set of more than 400,000 data of aperture distribution to create a digital twin of the system. These data are first subject to detailed statistical characterization, including standard geostatistical and fractal-based approaches. Experimental data of flow are quantitatively correlated to the key statistical features characterizing fracture geometry under various flow rates and normal loading conditions. Temporal monitoring of fluid saturation distribution enable us to provide a preliminary assessment of the impact of the material constituting the fracture wall (e.g., in terms of its wettability) on fluid saturation distribution.
Profiling mineral dust with UAV-based in-situ instrumentation (Cyprus Fall campaign 2021)
Authors: Kezoudi Maria , Papetta Alkistis , Marenco Franco , Keleshis Christos , Kandler Konrad , Girdwood Joe , Stopford Chris , Wienhold Frank , Ru-Shan Gao , Sciare Jean
Published: March 2022

Unmanned Aerial Vehicle (UAV)-sensor systems allow for cost-effective vertically-resolved in-situ atmospheric observations within the lower troposphere. Taking advantage of the private runway and dedicated airspace of the Unmanned Systems Research Laboratory (USRL; https://usrl.cyi.ac.cy/) of the Cyprus Institute in Orounda (Nicosia, Cyprus), an intensive campaign focusing on mineral dust observations was conducted between 18 October and 18 November 2021. This, involved UAV flights (36 in total) and ground-based active and passive remote-sensing observations during two distinct dust outbreaks over Cyprus.

The first dust event occurred between 25 October and 1 November 2021, and HYSPLIT back-trajectories revealed that the observed air masses were mainly originated from NE Sahara (Libya, Egypt). The second dust event was observed from 13 to 18 November 2021. HYSPLIT back-trajectories revealed that the observed air masses at the beginning of the second event were originated from the Middle East (Saudi Arabia, Syria), but the air mass origin switched to NW Saharan dust midways through the event. The Aerosol Optical Depth at 500-nm as measured by our sun-photometers was found to be above 0.2 all the time, and in some days reached up to 0.5. The observed aerosol layers were found to be extending from ground up to 5 km Above Sea Level (ASL).

This study presents results of the vertical aerosol structure/height-resolved information of each dust event from its arrival to its departure as observed by instruments on-board the UAVs including: a pair of Universal Cloud and Aerosol Sounding System (UCASS) Optical Particle Counters (OPCs), Printed Optical Particle Spectrometer (POPS) OPC, Compact Optical Backscatter AerosoL Detector (COBALD) and filter samplers.
Measuring interseismic deformation of the Dead Sea fault from along-track Sentinel-1 TOPS interferometry
Authors: Li Xing , Jónsson Sigurjón , Ma Zhangfeng , Masson Frédéric , Klinger Yann
Published: March 2022

The north-south component of ground deformation remains difficult to derive from InSAR due to the limited sensitivity of standard InSAR observations in that direction. The new approach of burst-overlap interferometry (BOI) exploits swath overlaps of the Sentinel-1 TOPS acquisition mode to retrieve accurate north-south displacements. We applied time-series analysis to such along-track BOI observations of the roughly north-trending Dead Sea fault. Using a large number of Sentinel-1 images acquired from both ascending and descending tracks, we retrieved the horizontal displacement in the burst-overlap areas. Mis-registration errors caused by orbit errors, timing errors, or tropospheric delays are limited in burst-overlap velocities, and ionospheric delays can be reduced through spatial averaging, enhancing the surface displacement estimation. However, interferometric decorrelation is a challenge, as it degrades the co-registration performance in addition leading to fewer observations, particularly near the northern Dead Sea fault. By exploiting hundreds of images, we find a clear and consistent velocity change across different segments of the Dead Sea fault, using coherent distributed scatters optimized by integrating temporal coherence. Modeling of the ascending and descending BOI velocity results suggests that the fault-parallel velocity is in the range 4.2-5.0 mm/yr south of the Lebanese restraining bend, whereas only about half of that to the north of it. The results demonstrate the applicability of BOI time-series analysis in medium-to-low coherence regions with low deformation rates.
Micro-scale characterization of vermiculite-rich sample from Granby Tuff, an analogue to Oxia Planum clays
Authors: Bultel Benjamin , Krzesinska Agata , Veneranda Marco , Loizeau Damien , Pilorget Cédric , Hamm Vincent , Lourit Lionel , Lequertier Guillaume , Bibring Jean-Pierre , Werner Stephanie C.
Published: March 2022

In 2022, ESA/ROSCOSMOS will launch ExoMars2022 rover mission to Mars. The selected landing site for the mission is Oxia Planum, a Noachian, phyllosilicate-bearing plain located between Mawrth Vallis and Ares Vallis. The Fe,Mg-rich clay mineral detected at Oxia Planum are one of the largest exposures of this type on Mars. They clearly record past water-rock interactions and as such are promising target to answer scientific questions that are the objectives of the ExoMars 2022 mission in terms of past water-rich environment and both ancient and present habitability of the planet.

NIR spectral features of the phyllosilicates at Oxia suggest some kind of Fe-rich vermiculite and/or saponite. Survey of Fe-rich terrestrial vermiculite-bearing rocks and characterization by powder near-infrared and X ray diffraction analyses (Krzesinska et al, 2021) showed that the best spectral analogy is shown by the basaltic tuffs from Granby, Massachusetts, USA. The tuffs have been altered and Fe-rich clays resides in amygdales of supposedly hydrothermal origin (April and Keller, 1991).

The analogue was incorporated to the Planetary Terrestrial Analogue Library (PTAL) collection (Dypvik et al., 2021, www.ptal.eu). As a part of collection, it is further characterized for purposes of supporting the ExoMars mission science.

As shown by bulk analysis of powdered samples, Granby tuffs represent fine-scale mixture of phyllosilicates (Krzesinska et al., 2021). Based on bands between 2.3 and 2.5µm in NIR, vermiculite and saponite are intergrowing with various proportions. For Oxia Planum, better spectral match is shown by samples dominated by vermiculite rather than mixed with saponite.

Here we report an in-situ, micron-scale combined analysis on the same sample by the instrument of MicrOmega (NIR), RLS (RAMAN) completed by sub-micron EDX analysis. Such analysis allows a more detailed characterization of phyllosilicate constituents and understanding their spectral manifestation. This is important to prepare the future in situ scientific investigations on Mars and will also bring a better understanding of the Granby clays that could represent a unique bridge of solid solution between chlorite and saponite (April and Keller, 1991).