bluuebunny/crossref_metadata_2025 huggingface dataset:
Dramatic decline and change in coiling direction of planktic foraminifer Morozovella at the Early Eocene Climatic Optimum (EECO; ~53-49 Ma) from the Pacific Ocean
Authors: Filippi Giulia , Luciani Valeria , D'Onofrio Roberta , Westerhold Thomas , Wade Bridget S. , Dickens Gerald R.
Published: March 2022

Improved knowledge of the connection between striking variations in the abundance and coiling direction of the trochospiral planktic foraminiferal genus Morozovella and early Eocene carbon-cycle changes, is presented in this study as deriving from new data recorded from the Pacific Ocean (Shatsky Rise, Ocean Drilling Program Sites 1209, 1210). This location spans the Early Eocene Climatic Optimum (EECO; ~53-49 Ma), the interval when Earth surface temperatures and atmospheric pCO2 reached the maximum peak of entire Cenozoic (Zachos et al., 2001, Sciences; Anagnostou et al. 2016, Nature; Inglis et al., 2020 Clim. Past). A significative impact of the EECO on planktic foraminiferal assemblages has recently been recorded in previous works from the Atlantic Ocean, where a definitive marked decline in abundance, diversity, test-size and change in coiling direction of the mixed-layer symbiont-bearing genus Morozovella, took place within the first ~600 kyr of this interval (Luciani et al., 2016 Clim. Past; Luciani et al. 2017 Paleoceanogr.; Luciani et al., 2017 GloPlaCha; D’Onofrio et al., 2020 Geosciences; Luciani et al., 2021 GloPlaCha). As registered in Atlantic sites, in the tropical Pacific Ocean Sites 1209 and 1210, the morozovellids drop permanently their relative abundance at the carbon isotope excursion (CIE) known as J event (~53 Ma), which marks the EECO beginning. A second major change affected all the morphologically defined species of Morozovella (possibly criptic species) at the Atlantic Ocean, resulting in a switch from dominant dextral to sinistrally coiling preference, within ~200 kyr after the K/X event (~52.8 Ma). Although the coiling direction preference of Morozovella at Shatsky Rise changed from dominant dextral to dominant sinistral after the K/X event as well as in the Atlantic sites, here the switch occurred with a delay of ~200 kyr. The recorded modifications clearly reflect important changes in evolution or environment. These changes may include temperature increase and pH decrease that could have reduced the symbiotic relationship and induced calcification crisis. Searching for the driving causes of the observed variations, our data clearly demonstrate their wide geographic and possibly global character and the evident relationship between the environmental perturbations occurred in the mixed-layer at the EECO and the striking changes on planktic foraminiferal assemblages during the first ~800 kyr of this intriguing interval.
Fully kinetic simulations of the near-Sun solar wind plasma: turbulence, reconnection, and particle heating
Authors: Franci Luca , Papini Emanuele , Micera Alfredo , Matteini Lorenzo , Stawarz Julia , Lapenta Giovanni , Burgess David , Hellinger Petr , Landi Simone , Verdini Andrea , Montagud-Camps Victor
Published: March 2022

We model the development of plasma turbulence in the near-Sun solar wind with high-resolution fully-kinetic particle-in-cell (PIC) simulations, initialised with plasma conditions measured by Parker Solar Probe during its first solar encounter (ion and electron plasma beta ≤ 1 and a large amplitude of the turbulent fluctuations). The power spectra of the plasma and electromagnetic fluctuations are characterized by multiple power-law intervals, with a transition and a considerable steepening in correspondence of the electron scales. In the same range of scales, the kurtosis of the magnetic fluctuations is observed to further increase, hinting at a higher level of intermittency. We observe a number of electron-only reconnection events, which are responsible for an increase of the electron temperature in the direction parallel to the ambient field. The total electron temperature, however, exhibits only a small increase due to the cooling of electrons in the perpendicular direction, leading to a strong temperature anisotropy. We also analyse the power spectra of the different terms of the electric field in the generalised Ohm’s law, their linear and nonlinear components, and their alignment, to get a deeper insight on the nature of the turbulent cascade. Finally, we compare our results with those from hybrid simulations with the same parameters, as well as with spacecraft observations.
IMPROVER : A probabilistic, multi-model post-processing system for meteorological forecasts
Authors: Moseley Stephen , Rust Fiona , Evans Gavin , Ayliffe Ben , Hurst Katharine , Howard Kathryn , Wright Bruce , Jackson Simon
Published: March 2022

The UK Met Office is developing an open-source probability-based post-processing system called IMPROVER to exploit convection permitting, hourly cycling ensemble forecasts. The system is tasked with blending these forecasts with both deterministic nowcast data, and coarser resolution global ensemble model data, to produce seamless probabilistic forecasts from the very short to medium range.

A majority of the post-processing within IMPROVER is performed on gridded forecasts, with site-specific forecasts extracted as a final step, helping to ensure consistency. IMPROVER delivers a wide range of probabilistic products to both operational meteorologists and as input to automated forecast production. and this presentation will detail some of the work that has been undertaken in the past year to prepare, with a focus on the use of statistical post-processing.

Statistical post-processing plays two complimentary roles within IMPROVER; ensuring forecasts better reflect reality, and in so doing, bringing different models into better alignment, which improves the seamlessness of model transitions. For a selection of diagnostics, the gridded forecasts from different source models are calibrated independently using ensemble model output statistics (EMOS). Results of experiments looking at the calibration of gridded forecasts will be discussed briefly.

More recently calibration of site forecasts has been introduced as a final step for temperature and wind speed forecasts. Results of experiments using EMOS to perform calibration in a variety of different ways will be presented, including justifications and trade-offs made in choosing a final approach.

This will include some discussion of the remaking of weather symbol products as period, rather than instantaneous, forecasts and the implications for their verification.
Insights on the role of thermal stresses during the evolution of magmatic-hydrothermal systems around upper crustal intrusions, based on 2D thermo-mechanical-chemical coupled numerical models 
Authors: Kiss Dániel , Moulas Evangelos , Rummel Lisa , Kaus Boris
Published: March 2022

Studies of host rock deformation near magmatic intrusions traditionally focus on stresses directly related to the intrusion process, either by directly considering inflating volumes or by considering two-phase deformation related to magma transfer. Thermal processes, especially volume changes due to thermal expansion or volume changes during partial melting/solidification are typically ignored in these studies. Here we show that thermal stresses around a rapidly emplaced upper crustal intrusion are significant and likely sufficient to create an extensive fracture network around the intrusion by brittle yielding. At the same time due to its cooling, the intrusion suffers significant decompression, resulting in low P – high T conditions, which could promote the appearance of a volatile phase. The appearance of a volatile phase and the development of a fracture network around the inclusion might be the processes that control magmatic-hydrothermal alteration around intrusions, and hence thermal stresses likely play an important role in the development of magmatic systems.

We present 2D numerical simulations of an upper crustal magma (or mush) body in a visco-elasto-plastic host rock, with coupled thermal, mechanical and chemical processes, accounting for thermodynamically consistent material parameters. The magma body is isolated from deeper sources of magma hence it is cooling, and thus shrinking. We quantify the pressure changes and stresses induced by such volume changes, and resolve fracture networks potentially developing as a result. We are considering more idealized/simplistic and more realistic geomteries and rheological, thermodynamic models alike.

We present solutions based on a self-consistent system of conservation equations for coupled thermo-mechanical-chemical processes, under the assumptions of slow (negligible inertial forces), visco-elasto-plastic deformation and constant chemical bulk composition. The thermodynamic melting/crystallization model is based on a granitic composition. We will briefly discuss the numerical implementation of thermodynamic data and volumetric plasticity (including tensile and dilational shear plasticity) in a self-consistent manner and illustrate the effect of volume changes due to temperature changes (including the possibility of melting and crystallization) on stress and pressure evolution in magmatic systems.
Lag time in evacuation of coarse sediment generated by large earthquakes: a case study of the Melamchi River (central Nepal)
Authors: Graf Emma , Sinclair Hugh , Attal Mikael
Published: March 2022

Large earthquakes can contribute to mountain growth by building topography, but also contribute to mass removal from mountain ranges through widespread mass wasting. On a shorter timescale, large earthquakes also have the potential to significantly alter fluvial sediment dynamics if a significant volume of the sediment generated reaches the fluvial network. For example, up to 18 m of channel bed aggradation were observed following the 1999 Chi-Chi (Taiwan) earthquake. In this contribution, we focus on the Melamchi River in central Nepal. This catchment experienced widespread landsliding associated with the 2015 Gorkha (Nepal) earthquake, and was struck by a devastating high concentration flow in June 2021, resulting in up to 15 m of channel aggradation. Using a time series of high-resolution satellite imagery, we have mapped exposed gravel along the river from 2012-2021 to identify zones of channel aggradation and document changes over time. We show that the increase in exposed gravel following the 2015 earthquake is negligible compared to the signal associated with the 2021 event. We consider whether the scale of the high concentration flow event was amplified by the Gorkha earthquake preconditioning the landscape for large-scale sediment evacuation, which raises the question of whether an event such as the Melamchi disaster could occur in other Gorkha-affected catchments. 
Role of soil biofilms in the transport processes of emerging organic contaminants: A laboratory experimental study
Authors: Muñoz-Vega Edinsson , Spada Lucas , Schulz Stephan , Schüth Christoph
Published: March 2022

Over the last two decades there has been a growing interest in the occurrence and fate of emerging organic contaminants (EOCs) in groundwater globally. Managed aquifer recharge (MAR) has been recognized as one of the possible causes of pollution, because of the use of insufficiently or partially treated waters as infiltration source.

Biofilms are one of the most widely distributed modes of life on Earth, and they drive biogeochemical cycling processes of most elements in water, soil, sediment and subsurface environments. Biofilms are aggregates of microorganisms in which cells are frequently embedded in a self-produced matrix of extracellular polymeric substances (EPS). Biofilms partially cover the underlying material, changing the sorption behavior of the soil surface and giving a proper environment to microorganisms for the degradation of EOCs.

To understand the role of biofilms in the transport processes of EOCs, we performed batches studies and a set of three saturated column experiments where biofilms were established. Two of the columns were filled with a soil having a high organic content (0.6% organic carbon) and the third one contained the same soil but muffled, to characterize the role of organic matter in the growth of biofilms. The feed water consisted of ten-fold diluted synthetic wastewater (SWW) without EOCs, and in the case of one of the organic columns, sodium azide was spiked to have an abiotic control. The columns were equipped with automated sensors (high resolution oxidation-reduction potential, water pressure and soil pH) to link these variables to biofilm development. Several tracer experiments were run during the duration of the experiments and analysis of major ions, organic carbon and trace elements were performed as well. After hydrogeochemical equilibrium was reached in each column, inflow SWW was spiked with a cocktail of five EOCs in environmental concentrations (µg/L), covering different hydrophobicity, speciation and biodegradability parameters: Carbamazepine, Metoprolol, BP3, Ibuprofen and Diclofenac.  Breakthrough curves of the EOCs were measured, and double porosity models were fitted to compare retardation factors and rates of degradation of each system. Post experiments analysis allowed the determination of the biofilms on each column by means of EPS extraction and quantification. Differences in the transport behavior of most of the compounds were observed between the columns, concluding that biofilms and biological structures can be an important factor in the transport of EOCs in soils.
Bayesian parameter inference in hydrological modelling using a Hamiltonian Monte Carlo approach with a stochastic rain model
Authors: Ulzega Simone , Albert Carlo
Published: March 2022

Conceptual models are indispensable tools for hydrology. In order to use them for making probabilistic predictions, they need to be equipped with an adequate error model, which, for ease of inference, is traditionally formulated as an additive error on the output (discharge). However, the main sources of uncertainty in hydrological modelling are typically not to be found on the output, but on the input (rain) and in the model structure. Therefore, more reliable error models and probabilistic predictions can be obtained by incorporating those uncertainties directly where they arise, that is, into the model. This, however, leads us to stochastic models, which render traditional inference algorithms such as the Metropolis algorithm infeasible due to their expensive likelihood functions. However, thanks to recent advancements in algorithms and computing power, full-fledged Bayesian inference with stochastic models is no longer off-limit for hydrological applications. We demonstrate this with a case study from urban hydrology, for which we employ a highly efficient Hamiltonian Monte Carlo inference algorithm with a time-scale separation.
Normal mode models of the mantle using Backus-Gilbert tomography
Authors: Restelli Federica , Koelemeijer Paula , Zaroli Christophe
Published: March 2022

Seismic tomography is a powerful tool to study the deep Earth, given the lack of direct observations. Seismic structures can be interpreted together with constraints from other disciplines, such as geodynamics and mineral physics, to provides valuable information about the structure, dynamics and evolution of the mantle. Nevertheless, a robust physical interpretation of seismic images remains challenging as tomographic models typically lack uncertainty information and may have biased amplitudes due to uneven data coverage and regularisation.

We aim to build tomographic models of the mantle with associated uncertainties and unbiased amplitudes. For this, we use the SOLA method (Zaroli, 2016) applied to normal mode data, the Earth’s free oscillations. SOLA is based on a Backus-Gilbert approach, which explicitly constrains the amplitudes to be unbiased and inherently computes the model uncertainty and resolution. This approach enables us to perform meaningful physical interpretations of the imaged structures. By applying this method to normal modes, we obtain valuable insights on the long wavelength structure of the mantle. The use of normal modes also has several advantages: these data are sensitive to multiple parameters, including both Vs and Vp anisotropy as well as density, and they provide global data coverage.

Here, we report on our progress towards a new 3-D mantle model based on the inversion of normal mode splitting function data. We discuss initial results from synthetic tests and isotropic inversions in terms of model estimates, uncertainties and resolution.
Evaluation of different forecasting approaches in predicting the spring flood in Northern Sweden
Authors: Yang Wei , Foster Kean , Pechlivanidis Ilias G
Published: March 2022

About 70% of the annual streamflow volume in Northern Sweden is generated during the spring flood (i.e., May-July), and consequently this relatively short period is of great significance to the hydropower industry. Moreover, the mismatch in the timing between the energy demand and the natural streamflow generation, as well as the condition to regulate the reservoirs for flooding control, make the storage management challenging.

Over the past years, different methodologies have been developed to enhance the skilfulness of seasonal hydrological forecasts. Ensemble streamflow prediction (ESP) is a well-established approach in which a hydrological model is forced with historical meteorological observations, hence representing a climatological evolution constrained by the initial hydrological conditions. In addition, dynamic forecasting employs bias-adjusted (at least in most cases) seasonal forecasts of daily precipitation and temperature from Global Circulation Models (GCM) to force a hydrological model to estimate the hydrological evolution. Moreover, statistical forecasting is based on deriving links between predictors and predictands, for instance large-scale atmospheric variables and observed spring flooding volume can be used to make forecasts of the seasonal inflow volumes. Another approach is based on analogue conditioned ESP (A-ESP) and uses hydrological weather regimes (HWRs) as a condition to select analogues from the historical ensemble of meteorological observations and combining these together with the ESP to create a weighted ESP. The HWRs are based on large-scale circulation patterns and optimized using local precipitation observations.

Here, we compare the A-ESP approach against statistical and dynamic forecasting approaches in predicting the spring flood in 84 sub-catchments in Northern Sweden. The forecast skills are assessed by using the traditional ESP approach as a benchmark. The results show that: (1) the A-ESP can improve forecast skill at all lead-times, (2) statistical forecasting is of most benefit for forecasts with long lead-times, and (3) dynamic forecasting has limited skill at short lead-times. 
Assessment of infrastructure-based reductions of future heat wave intensity with advanced mesoscale modelling
Authors: Krayenhoff E. Scott , Jiang Timothy , Martilli Alberto , Moede Christian , Demuzere Matthias
Published: March 2022

Future urban climates are likely to warm substantively in coming decades as a result of climate change, and greater heat wave severity is anticipated. Moreover, the urban heat island contributes additional heat, especially during evening and night. Infrastructure-based heat reduction strategies can reduce canopy air temperatures during daytime, and to some extent at night. These strategies also have several additional effects beyond air temperature reduction. Here, we apply an early coupling of the WRF mesoscale model with the BEP-Tree urban canopy model to simulate extreme heat events representative of both contemporary and projected future climates for the metropolitan region of Toronto, Canada. Urban and non-urban land cover is derived using the state-of-the-art LCZ Generator methodology. Subsequently, the effectiveness of heat mitigation strategies, including highly reflective surfaces and vegetation, is quantified for the future scenario in the context of the increase in heat wave intensity. Specifically, the neighbourhood- and city-scale climate impacts of street trees across the diurnal cycle are quantified, and the diurnal progression of their local climate effects is discussed with reference to their modifications to multiple physical processes in the canopy. Effects of all heat mitigation strategies on canopy climate, building energy use, and thermal comfort indices are evaluated.
Stochastic Modeling of Stratospheric Temperature
Authors: Eggen Mari , Rognlien Dahl Kristina , Näsholm Sven Peter , Mæland Steffen
Published: March 2022

This study suggests a stochastic model for time series of daily zonal (circumpolar) mean stratospheric temperature at a given pressure level. It can be seen as an extension of previous studies which have developed stochastic models for surface temperatures. The proposed model is a combination of a deterministic seasonality function and a Lévy-driven multidimensional Ornstein–Uhlenbeck process, which is a mean-reverting stochastic process. More specifically, the deseasonalized temperature model is an order 4 continuous-time autoregressive model, meaning that the stratospheric temperature is modeled to be directly dependent on the temperature over four preceding days, while the model’s longer-range memory stems from its recursive nature. This study is based on temperature data from the European Centre for Medium-Range Weather Forecasts ERA-Interim reanalysis model product. The residuals of the autoregressive model are well represented by normal inverse Gaussian-distributed random variables scaled with a time-dependent volatility function. A monthly variability in speed of mean reversion of stratospheric temperature is found, hence suggesting a generalization of the fourth-order continuous-time autoregressive model. A stochastic stratospheric temperature model, as proposed in this paper, can be used in geophysical analyses to improve the understanding of stratospheric dynamics. In particular, such characterizations of stratospheric temperature may be a step towards greater insight in modeling and prediction of large-scale middle atmospheric events, such as sudden stratospheric warming. Through stratosphere–troposphere coupling, the stratosphere is hence a source of extended tropospheric predictability at weekly to monthly timescales, which is of great importance in several societal and industry sectors.
Realizing the impacts of early vegetation on global biogeochemical cycles through a process-based model (LYCOm)
Authors: Halder Suman , Dahl Tais Wittchen , Benca Jeffry , Porada Philipp
Published: March 2022

Lycopsids are one of the earliest occurring groups of vascular plants, encompassing a long evolutionary history from its early bushy herbaceous structures during the late Silurian into forests of tree-like structures in the Middle Devonian. These early plants may have contributed to substantial changes in the composition of Earth’s atmosphere, partly related to the biotic enhancement of weathering. To achieve a more quantitative assessment of the biogeochemical impacts of these organisms, it is necessary to quantify their physiological characteristics, spatial distribution, carbon balance, and their hydrological impacts during their span of evolution starting from the Silurian. Here, we present a process-based Lycopsid
Model (LYCOm), developed for the estimation of the influence of the Lycopsids on biogeochemical cycles, which has been applied at the global scale.
The model provides reasonable coverage of the lycopsids for today besides the estimation of weathering rates. The current model features ranges of
key physiological traits of lycopsids to predict the emerging characteristics of the Lycopsida community under any given climate by implicitly simulating the process of natural selection. In this way, extinct plant communities can also be represented. In addition to physiological properties, the model also simulates weathering rates using a simple limit-based approach and estimates the biotic enhancement of weathering by these plants. The model has been locally validated using net primary productivity from on-site observations. The model includes key features such as the distribution of biomass above and below ground, along with a plausible root distribution in the soil affecting water uptake by plants. LYCOm can simulate realistic properties of today’s lycopsid communities with Net Primary Production (NPP) ranging from 100 g carbon m−2 year−1 to 245 g carbon m−2 year−1. Our limit-based weathering model predicts a mean chemical weathering rate ranging up to 45.1 cm ka−1 rock, thereby highlighting the potential importance of such vegetation for the enhancement of chemical weathering. This step brings us closer to predicting the abundance and weathering impacts of the lycophytes in the geological past when they were prevalent. Although our method is fraught with some constraints and uncertainties, it represents a novel, complementary approach towards estimating the impacts of lycopsids on biogeochemistry and climate.
The causes of unexpected jökulhlaups, studied using geothermal reservoir modelling 
Authors: Reynolds Hannah Iona , Gudmundsson Magnús T. , Högnadóttir Thórdís
Published: March 2022

Jökulhlaups (glacier outburst floods) are considered the most common type of volcanic hazard in Iceland, and result from the accumulation of meltwater during long-term geothermal activity beneath glaciers, or very rapid melting over a short period of time. Jökulhlaups may occur without visible precursors or prior warning, varying in size from being persistent leakage to floods that have caused considerable damage like the jökulhlaups in Múlakvísl and Kaldakvísl in July 2011. Little has been known about the onset time of water accumulation/melting, whether water accumulated before it was released, and how these events are related to intrusion of magma. This study categorises known ice cauldrons within Icelandic glaciers based on their volume, rate of formation, and longevity. Geothermal reservoir modelling was then used to explore possible heat sources which generate the cauldrons. Five scenarios were simulated: (1) Subglacial eruption – freshly erupted magma in direct contact with the ice at the glacier base; (2) Intrusion into homogeneous bedrock - magma intrudes into a bedrock of homogeneous properties; (3) Intrusion into high permeability channel – similar to scenario (2) but a high permeability channel extends from the intrusion to the glacier-bedrock boundary, e.g. zone of high permeability at a caldera fault; (4) Sudden release of pressure – a hot reservoir is topped by caprock, with a high permeability pathway from depth up to the glacier-bedrock boundary, representing a sudden breach of a pressurised reservoir; and (5) Intrusion into a very hot reservoir – similar to scenario (3) but the reservoir is near boiling point, from previous repeated intrusive activity. This work improves our understanding of sudden and unexpected jökulhlaups, which is helpful for hazard assessments and response plans for unrest in glaciers near inhabited areas, tourist spots, and power plants. 
Robust trends in the number of winter days with heavy precipitation over Europe are modulated by a weaker NAO variability by the end of 21st century
Authors: Fuentes-Franco Ramon , Docquier David , Koenigk Torben , Giorgi Filippo , Zimmermann Klaus
Published: March 2022

We use 14 models participating in the Coupled Model Intercomparison Project phase 6 (CMIP6) to analyse the number of days with extreme winter precipitation over Europe and its relationship to the North Atlantic Oscillation (NAO), for the observed period 1950-2014 and 21st-century that for northern Europe, models project two times more extreme precipitation days by the end of the 21st century compared to the historical period (1950-2014). In contrast, no significant change in the number of extreme precipitation days is detected over the whole period for southern Europe. We find a weakening of the NAO variability in the second half of the 21st century compared to the historical period.  For the second half of the 21st century, models show an intensified correlation between the extreme precipitation and the NAO index in both southern and northern Europe. Models with a reduced variability of the NAO show an increased positive trend of days with extreme precipitation in northern Europe.
Nonstationarity in Global Hydrological Water Budget, Evidence-based on GRACE Satellite Mission
Authors: Hasan Emad , Save Himanshu , Tamisiea Mark , Bettadpur Srinivas
Published: March 2022

Anthropogenic climate change (ACC) has led to a significant shift in the hydrological water budget natural balance. The human-induced modifications in water systems, land cover, and land use have introduced the notion of “nonstationarity” in the hydrologic system. The concept implies significant changes in the hydrologic systems’ intra-annual and interannual variabilities with a time-variant mean, variance, and non-uniform density distribution. Under nonstationary conditions, extreme weather and climate events became frequent. Their magnitudes, durations, and frequencies are outside the historically observed ranges. A nonstationary system displays a volatile memory that hinders any reliable future projections. We revaluate the nonstationarity in global hydrological systems using gravity measurements from the GRACE (Gravity Recovery and Climate Experiment) mission. We utilized GRACE mascons (mass concentration blocks) solutions of RL06 from the Center for Space Research (CSR) between April 2002 to June 2017. We employed the KPSS and the ADF tests for stationarity in deterministic and periodic components, respectively. The KPSS test identified 25 hotspots globally that are nonstationary around the deterministic trend. These hotspot locations have undergone extensive anthropogenic activities on the available freshwater resources. The ADF test mapped the nonstationary systems around the mean and the variance components in 11 hotspot locations. These locations are noted by the KPSS test as nonstationary systems around the trend as well. Understanding the nonstationary state in hydrologic systems will enhance our awareness and preparedness to mitigate future extremes.
A novel fitting procedure for soil hydraulic properties with improved parameter uncertainty assessment
Authors: Inforsato Leonardo , de Jong van Lier Quirijn , Durner Wolfgang
Published: March 2022

Equations for soil hydraulic properties are used to numerically solve the Richards equation. Uncertainties in the parameters that compose these mathematical models propagate into simulation results and their quantification is important. Parameter fitting is usually done using measured data of conductivity (K), matric potential (h), and/or water content (q). Solvers that use derivatives in the fitting process estimate the parameter uncertainties based on the Hessian matrix and the covariance matrix. This procedure considers the uncertainties of the parameters have a normal distribution, and the precision of the parameter predictions are expressed as standard deviations and correlated by a correlation matrix. This approximation is acceptable when reliable data is available, but it is not true for scenarios with higher uncertainties in the original data. We developed a new method to fit the most commonly used models for the q, h, K relationships with a sigmoidal function for the q – h retention function. To approach the parameter uncertainty distribution to a normal distribution, a transformation is applied to the parameters and bootstrapping is used to generate the parameter uncertainty distribution. The transformation shows a better performance according to Shapiro‑Wilk and D'Agostino's test. Another improvement was obtained by using two arbitrary points instead of qs and qr to anchor the retention function. When the two anchoring points are selected within the range of the measured data used for the regression, a lower uncertainty for the fitted parameters resulted. The choice of the anchoring points also impacted the correlation matrix.
How fast do Trawlmarks degenerate? A field study in muddy sediments near Fehmarn Island, German.
Authors: Schönke Mischa , Clemens David , Feldens Peter
Published: March 2022

Bottom trawling is a fishing technique in which a net held open by otter boards is dragged across the seafloor to harvest bottom living resources. This action induces high levels of stress to ecosystems by overturning boulders, disturbing and resuspending surface sediment, and plowing scars into the seabed. In the long term the trawling impact on benthic habitats becomes problematic when the time between trawls is shorter than the time it takes for the ecosystem to recover. Since quantitative information on the intensity of bottom fishing is particularly important but rarely available, our study is crucial to reveal the extent and magnitude of the anthropogenic impacts to the seafloor. As part of the MGF Baltic Sea project, a multibeam-echosounder was used to record high-resolution bathymetric data in a small, heavily fished focus area at a 1-year interval. Based on bathymetric data, we present an automated workflow for extracting trawlmark features from seafloor morphology and deriving parameters that qualitatively characterize trawlmark intensity. We also demonstrate how the seafloor surface of an exploited area develops within a year and what can be derived from this for regeneration indicators.
The Impacts of the 2017 Catastrophic Fire Season in Portugal on Vegetation Productivity
Authors: Ermitão Tiago , Gouveia Célia , Russo Ana
Published: March 2022

Wildfires have become a serious threat to ecosystems and human society over the last years of the 21st century, with many hectares being destroyed every year globally. The lengthening of the fire seasons and the increase of wildfires risk, which have been promoted by climate change, input many losses on society, economy and mostly in diverse ecosystems. In Portugal, the 2017 catastrophic fire season burned more than 450,000 hectares and caused the death of more than 100 people. In this context, relying on remotely sense products from MODIS collections, our study proposes an analysis of the effect of summer heat and water availability deficit in vegetation productivity decline that led to large fires propagation, especially in June and October of 2017. With the aim to evaluate the magnitude of the impact that compound or cascading extreme events had on the vegetation productivity decline, considering the 2001-2019 historical values, we defined three different classes of pixels that should reflect the conditions before the fire: affected by hot, by dry or by hot/dry conditions. Moreover, we assess the influence of favourable winter/spring meteorological conditions on enhancing vegetation productivity that promote high fuel accumulations susceptible to burn some months later. Our results reinforce the water and energy dependency of the vegetation of the region during the growing season and highlight that the combination of higher temperatures and water availability in spring can trigger summer wildfires propagation, flammability and intensity due to the accumulation of biomass. Considering that the example of 2017 can be more recurrent under the context of climate change, this study also highlights the need to improve the awareness strategies in fire prone regions like Portugal, especially on biomass accumulation control during growing season.

This study was supported by national funds through FCT (Fundação para a Ciência e a Tecnologia, Portugal) under project FIRECAST (PCIF/GRF/0204/2017) and IMPECAF (PTDC/CTA-CLI/28902/2017).
Ecosystems for disaster risk reduction: what is the scientific evidence?
Authors: Sudmeier-Rieux Dr. Karen ,   Co-authors
Published: March 2022

Calls are rising for ecosystems, or green infrastructure, to complement engineered infrastructure for more effective disaster risk reduction and climate governance. Key international framework agreements, including the Sendai Framework for Disaster Risk Reduction 2015-2030 and the 2021 Glasgow Pact, noted the importance of ensuring the integrity of all ecosystems in addressing climate change and disaster risk. For example, vegetation can stabilize slopes to reduce mountain hazards and sand dunes, mangroves, and/or seagrasses can reduce the impacts of coastal storms.  However, there are gaps in the scientific evidence on this topic with few comprehensive, peer-reviewed studies to support decision-making on green infrastructure for disaster risk reduction.

This study systematically reviews 529 English-language articles published between 2000 and 2019. The objective was to catalogue the extent of knowledge and confidence in the role of ecosystems in reducing disaster risk. The main question this review addresses is: What is the evidence of the role that ecosystem services and/or functions contribute to disaster risk reduction? We modified the review methodology established by the Intergovernmental Panel on Climate Change to identify the robustness of evidence and level of agreement on the role of ecosystems in attenuating most common types of hazards.

The data demonstrate very robust links on the role of ecosystems in forest fire management, urban flooding and slope stabilization to reduce mountain hazards in a cost-effective manner. The study also highlights how ecosystems provide multiple services and functions in addition to regulating hazards, e.g., provisioning services for reducing vulnerability. The review highlights several research gaps, notably a geographic concentration of studies on urban areas of Europe and North America, and insufficient policy-relevant research on coastal, dryland, and watershed areas, especially in Asia, Africa and Latin America. To conclude, more attention should be paid to filling these research gaps and developing performance standards, which would provide policy-makers with increased confidence in investing in green infrastructure for disaster risk reduction and climate governance.
Mapping Flooding and Inundation Dynamics Using Spaceborne GNSS-R Observations
Authors: Chew Clara , Small Eric
Published: March 2022

Even the youngest child knows that fresh water is crucial for life, and it’s easy to see and appreciate our reservoirs, lakes, and rivers for the numerous services they provide, not only for drinking water but also for transportation and the health of our ecosystems. But inland surface water is both a friend and a foe. Too much of it can be devastating for communities—floods are one of the costliest natural disasters, and they often disproportionally impact the most vulnerable members of those communities. Too little of it, though, can be just as destructive. Years-long droughts empty reservoirs, increase wildfire risk, and can lead to conflict over remaining water resources. Quantifying the amount and extent of inland surface water is thus important for knowing where we lie in this delicate balance between abundance and scarcity.

A variety of approaches to map flood and inundation dynamics already exist, be they stream gage data, hydrologic models, or remote sensing observations from satellites. All of them have advantages and challenges, and none alone provide a complete picture of the extent of surface water at any one particular moment. This presentation will describe a new approach to mapping flooding and inundation dynamics, which can provide complementary information to that which already exists via other sensors, models, or networks. This approach uses spaceborne Global Navigation Satellite System-Reflectometry (GNSS-R) observations to infer surface water extent. Currently, the vast majority of spaceborne GNSS-R data come from the Cyclone GNSS (CYGNSS) constellation, a NASA mission comprised of eight small satellites orbiting the tropics.  Here, we will present flood inundation maps derived from CYGNSS data for the full period of record (2017 – present), which are gridded to three km and have a temporal revisit rate of three days. We will discuss the retrieval algorithm, its validation, limitations of our approach, and plans to disseminate the data to the public. Finally, we will comment on the potential of GNSS-R data beyond CYGNSS to provide hydrologic information to the broader research community and other end users.
Erosion and Weathering of the Himalaya and Tibetan Plateau is not the Cause of Neogene Global Cooling
Authors: Clift Peter , Jonell Tara
Published: March 2022

Does uplift and erosion of the Himalaya-Tibetan Plateau drive Cenozoic global cooling? We tested this classic hypothesis put forward by Raymo and Ruddiman (1992) that suggests enhanced erosion in the Himalaya-Tibetan Plateau drove long-term Cenozoic global cooling through the chemical weathering of siliciclastic sediment. Here we examine three Asian marginal drainage systems (the Indus, Mekong and Pearl) where marine scientific drilling has yielded detailed seismic surveys and geochemical datasets that critically permit sediment mass flux and therefore chemical weathering flux budgets to be made. By compiling suitable bedrock endmember compositions for the fresh bedrock sources and proximal modern river sediments, it is possible to calculate the chemical weathering flux and relative CO2 consumption rates for each drainage system into the early Miocene. We correct for evolving provenance of sediment delivered to the offshore and test the sensitivity of our calculations to selected bedrock endmembers, in light of the abundant mafic bedrock exposed Indus and Mekong systems. The Indus shows a progressive shift away from erosion of the Karakoram to the Himalaya. Appropriate Upper Continental Crust endmembers were further validated using data compiled from the GEOROC database. Regardless of which endmembers were used, calculations demonstrate that the total rate of CO2consumption decreased by 50% between ~16 and 5.3 Ma, especially within the NW Himalaya as erosion slowed and provenance shifted away from mafic arc units in the suture zone. This direct test of the uplift-erosion-weathering hypothesis establishes that chemical weathering fluxes in this region did not increase during the Neogene and cannot be responsible for the drawdown of atmospheric CO2 during that time period. Either additional mechanisms have been driving global cooling since 16 Ma or CO2 consumption via chemical weathering is taking place in other areas outside the Himalaya-Tibetan Plateau.
The use of microseismic technology to optimize fracture connectivity in  unconventional reservoirs
Authors: Gomaa Mahmoud , Alhilali Ibrahim , AlEid Ali , Hamza Mohammed , Allam Sherif , Kaka SanLinn
Published: March 2022

The use of microseismic technology to optimize fracture connectivity in  unconventional reservoirs

Mahmoud Mowafi, Ibrahim Alhilali, Ali AlEid, Mohammed Hamza, Sherif Allam and SanLinn Kaka

College of Petroleum Engineering and Geosciences

King Fahd University of Petroleum and Minerals

Dhahran 31261, Saudi Arabia

 

Unconventional reservoirs represent a challenging scenario to optimize the subsurface connectivity and production efficiencies. Heterogeneity is one of the main factors impacting well capability. Furthermore, the size and quality of the interconnected fracture network consequently enhance reservoir stimulation and permeability. We undertake this study to review the impact and efficiency of microseismic monitoring technology in  1) determining the growth of hydraulic fracture, 2) enhancing the understanding of fracture networks,  3) evaluating risks, and  4) estimating the production values of unconventional resources.  We subsequently develop a workflow to predict the possible range of stimulated reservoir volume using available data compiled from various literature. Our data were mainly from   North American and  China. The data were processed and analyzed considering the variations in rock properties and the hydraulic fracturing designs. Fracture heights and growth geometry were identified. No significant variations within the fracture heights were noticed among different plays. The workflow developed in this study enables us to predict stimulated reservoir volume in order to optimize the fracturing design which plays an important role in improving the recovery ratio of unconventional reservoirs.
One station observation system for Mars exploration
Authors: Li Changcheng , Chen Xiaofei
Published: March 2022

    Since entering the 21st century, with the progress and development of science and technology. Human exploration of the world is not limited to the earth. Remarkable achievements have also been made in the exploration and understanding of the planet. In the last century, the US completed the exploration of the internal structure of the moon by using seismological methods through the Apollo program. The successful launch of insight in 2018 marked the birth of Marsquake, and realized the preliminary exploration of the internal structure of Mars. Due to the limitation of aerospace capability, the scientific research equipment we can carry is limited. The NASA spent hundreds of millions of dollars to deploy a seismograph on Mars. However, the deployment of a single seismograph is usually difficult to accurately measure the internal structure of Mars. Because the imaging method based on the internal vibration signal of Mars requires the use of a single seismograph constraining the source information and the internal structure of Mars at the same time, Which will increase the risk of inversion multiplicity.

    The main function of placing seismometers on the planet is to monitor the internal activity law of the planet. However, if we can obtain more reliable planetary exploration data without increasing the detection cost by designing a reasonable observation system, it will play an important role in the future exploration of the internal structure of the planet.

    Thus, a single station observation system is designed, which lays a foundation for seismic imaging to obtain more controllable and reliable data through the combination of single station and moving source(Rover). In this way, we can obtain two-dimensional and three-dimensional planetary seismic profiles in the future.

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