Solid Earth Geosciences

The annually held series of European Workshops on HPC Infrastructures (EWHPC) aim to bring together worldwide specialists in HPC centre design and operation to discuss the latest trends in infrastructure and supporting technologies for supercomputing centres. Due to the COVID-19 pandemic, the 11 th EWHPC was cancelled and a shorter online event was offered instead. It attracted more than 100 participants from 40 different HPC sites and provided a general overview on EuroHPC Joint Undertaking (JU) as well as updates on three EuroHPC JU pre-exascale consortia and their systems: Leonardo (hosted at CINECA), LUMI (hosted at CSC), and MareNostrum 5 (hosted at BSC). The EWHPC online event was held on 14 th of October and virtually collocated with an online PRACE Topical Session on "Exascale for European Datacentres" held on 15 October 2020, then followed by the traditional PRACE session on HPC infrastructures with technical presentations from PRACE sites on

The annually held series of European Workshops on HPC Infrastructures (EWHPC) aim to bring together worldwide specialists in HPC centre design and operation to discuss the latest trends in infrastructure and supporting technologies for supercomputing centres.<br> Due to the COVID-19 pandemic, the 11th EWHPC was cancelled and a shorter online event was offered instead. It attracted more than 100 participants from 40 different HPC sites and provided a general overview on EuroHPC Joint Undertaking (JU) as well as updates on three EuroHPC JU pre-exascale consortia and their systems: Leonardo (hosted at CINECA), LUMI (hosted at CSC), and MareNostrum 5 (hosted at BSC).<br> The EWHPC online event was held on 14th of October and virtually collocated with an online PRACE Topical Session on "Exascale for European Datacentres" held on 15 October 2020, then followed by the traditional PRACE session on HPC infrastructures with technical presentations from PRACE sites on 16 ...

Field visit, particularly scientific study, produces the finest results when it is carried out in the
field. Every aspiring environmental scientist must perform fieldwork in order to carefully and
accurately study and comprehend any part of the environment. Only by field observation can one
get this type of information. Our course, ENV-2102: Laboratory on Climate & Hydrological Data
Management, included this visit. One of the most significant meteorological departments in our
country is the Bangladesh Meteorological Department (BMD), which is essential for weather
forecasting and research about the climatic condition. The purpose of the approved meteorological
instruments at the field level, data interpretation and analysis to forecast our weather, and the
operations of BMD were all covered during this field visit. We went out in the field to observe
them in action. Only by field observation can one get this type of information. Every aspiring
environmental scientist must perform field research in order to fully comprehend any part of the
environment.

An extreme temperature is a weather phenomenon that is distinguished by marked cooling or heating of the air, or with the invasion of very cold or hot air, over a large area. The present study is associated with the simulation of regional climate using the Weather Research and Forecasting (WRF) model that was experimented through 30 different combinations of radiation parameterization schemes over Bangladesh. The intention was to investigate the response to the radiation parameters schemes for dynamic down-scaling of climatic variables. The predicted temperature of 30 different WRF setups were analyzed and compared with the Bangladesh Meteorological Department (BMD) recorded data and were found sensitive to the radiation physics on the basis of Root Mean Square Error (RMSE) at 2-meter air temperature

ExaHyPE (www.exahype.eu) is a Horizon 2020 EU project to develop a high-performance engine to solve hyperbolic systems of PDEs using the high-order discontinuous Galerkin finite element method. The project’s goals are to develop an engine with flexible support for various applications which shall be tailored towards expected exascale architectures. The user is provided with an abstraction of the complicated algorithms to implement the ADER-DG numerical scheme and of the issues related to scalability and parallel adaptive mesh refinement (AMR), which are handled internally by the Peano framework (www.peano-framework.org).

This study aims to improve our knowledge of the subsurface geology, and to
create a comprehensive geological framework to highlight potential
opportunities in the region. It involved analyzing the electrical and magnetic
parameters of the subsurface formations, comparing dipole-dipole electrical
resistivity and Schlumberger borehole data with magnetic data, and then
determining the level of alteration using conductive and resistant
anomalies. The results reveal that the area is characterized by resistant
anomalies and a high magnetic field of felsic formations, extending over a total
area of 85.56 ha and covered by a thick layer of alteration averaging 15 m in
depth. These formations span the entirety of the eastern portion of the study
area and isolated areas situated to the west and southwest. A major network
of fractures running NE-SW and NNE-SSW was highlighted through the
analysis of the conductive anomalies. Overall, this study has enabled us to use
a geophysical approach to distinguish the spatial distribution of the sound
lithological series in the area, the degree of alteration of the series, and the
related fracture and fault systems, which could serve as a valuable guide for
any mineral resource and aggregate exploration activity in the region.

Keywords : electrical resistivity, Magnetic anomalies, felsic rock, Toumodi region.

This study assesses a Continuous Data Assimilation (CDA) dynamical-downscaling algorithm for enhancing the simulation of the Indian summer monsoon (ISM) system. CDA is a mathematically rigorous technique that has been recently introduced to constrain the large-scale features of high-resolution atmospheric models with coarse spatial scale data. It is similar to spectral nudging but does not require any spectral decomposition for scales separation. This is expected to be particularly relevant for ISM, which involves various interactions between large-scale circulations and regional physical processes. Along with a control simulation, several downscaling simulations were conducted with the Weather Research and Forecasting (WRF) model configured over the Indian monsoon region at 10-km horizontal resolution using CDA, spectral (retaining different wavenumbers) and grid nudging for three contrasting ISM rainfall seasons: normal (2016), excess (2013), and drought (2009). The simulations are nested within the global NCEP Final Analysis data available at 1 º x 1 º horizontal resolution. The model outputs are evaluated against the India Meteorological Department (IMD) gridded precipitation and the fifth generation ECMWF atmospheric reanalysis (ERA-5). Compared to grid and spectral nudging, the simulations using CDA produce enhanced ISM features over the Indian subcontinent including the low-level jet, tropical easterly jet, easterly wind shear, and rainfall distributions for all investigated ISM seasons. The major ISM processes, in particular the monsoon inversion over the Arabian Sea, tropospheric temperature gradients and moist static energy over central India, and zonal wind shear over the monsoon region, are all better simulated with CDA. Spectral nudging outputs are found to be sensitive to the choice of the wavenumber, requiring careful tuning to provide robust simulations of the ISM system. In contrast, control and grid nudging generally fail to well reproduce some of the main ISM features.

A cold wave is a weather phenomenon that is distinguished by marked cooling of the air, or with the invasion of very cold air, over a large area. In the present study, the Weather Research and Forecasting (WRF) model was tested through 30 different combinations of radiation parameterization schemes to simulate the regional climate over the Bangladesh. The objective was to investigate the response to the radiation parameters schemes for dynamic down-scaling of climatic variables. The temperature from the 30 different WRF setups were compared with the BMD observed data and were found sensitive to the radiation physics. The 30 combination of radiation physics along with the fixed WRF Single-moment 3-class microphysics, Kain-Fritiches cumulus physics, Noah Land Surface Physics and YSU planetary boundary-layer physics produced comparable results for 02 to

This study evaluates the short-to-medium range precipitation forecasts from Global Forecast System for 14 major transboundary river basins in Africa against GPM IMERG "Early", IMERG "Final", and CHIRPSv2 products. Daily precipitation forecasts with lead times of 1-day, 5-day, 10-day, and 15-day and accumulated precipitation forecasts with periods of 1-day, 5-day, 10-day, and 15-day are investigated. The 14 selected basins are (1) Senegal; (2) Volta; (3) Niger; (4) Chad; (5) Nile; (6) Awash; (7) Congo; (8) Omo Gibe; (9) Tana; (10) Pangani; (11) Zambezi; (12) Okavango; (13) Limpopo and (14) Orange. For each basin, several sub-basins are defined by the major dams in the basin. Our preliminary results in the Nile river basin show that in terms of temporal variability, there was a good agreement between the forecasted and observed accumulated precipitation on a 15-day basis. When compared to IMERG "Final", the correlation coefficients of accumulated GFS forecasts scored as high as 0.75. Thus, GFS products provide relatively reliable accumulated precipitation forecasts. However, the precipitation forecasts were mostly biased: they tend to overpredict rainfall for the eastern part of the Nile river, underestimate rainfall for the northern part of the Nile river and produce almost unbiased estimates for the southern part of the river. Additionally, GFS forecasts have a general tendency to underpredict the area of precipitation across the Nile basin. Although the performance of GFS varies at different locations, the GFS precipitation forecasts can be a good reference to dam operators in Africa.

Seismic anisotropy provides key information to map the trajectories of mantle flow and understand the evolution of our planet. While the presence of anisotropy in the uppermost mantle is well-established, the existence and nature of anisotropy in the transition zone and uppermost lower mantle are still debated. Here we use 3-D global seismic tomography images based on a large data set sensitive to this region to show the ubiquitous presence of anisotropy in the lower mantle beneath subduction zones. Whereas above the 660-km seismic discontinuity slabs are associated with faster SV anomalies up to about 3%, in the lower mantle faster SH anomalies of about 2% persist near slabs down to about 1,000-1,200 km. These observations are consistent with 3-D 1 numerical models of deformation from subducting slabs and the associated lattice preferred orientation of bridgmanite produced in the dislocation creep regime in areas subjected to high stresses. This study provides evidence that dislocation creep may be active in the Earth's lower mantle, providing new constraints on the debated nature of deformation in this key but inaccessible component of the deep Earth. The Earth's upper and lower mantle have quite distinct physical properties, with the characteristics of material exchange between them being a long-debated issue. Progress in global seismic tomography in the 1990s 1,2 showed that the upper and lower mantle interact mainly via subducting slabs and mantle plumes, albeit subject to the presence of strong resistance along the upper-lower mantle boundary at ∼660 km depth. More recently, enhanced tomography images showed that amongst the slabs that penetrate into the lower mantle, many of them stagnate down to about ∼1,000 km depth 3. Conversely, mantle plumes rising from the deep lower mantle seem to deflect laterally when they reach this region 4. However, the uppermost lower mantle, located at depths of ∼660-1,000 km, remains an enigmatic part of the Earth. It has been suggested that compositional layering 5,6 or a viscosity increase 7,8 may cause flow stagnation in this region, but its rheology and role in mantle convection are poorly understood. The stagnation of subducting slabs at ∼660 km depth and their penetration into the lower mantle lead to intense strain and deformation around the slabs, which in turn can align mineral aggregates. Since the most abundant lower mantle mineral (bridgmanite) is anisotropic, observable seismic anisotropy should develop when considering a dislocation creep deformation mechanism 9,10,11. However, apart from the D" region in the lowermost mantle 12 , the presence of seismic anisotropy in the lower mantle is uncertain and debated 13,14,15 , with most previous seismological models suggesting that the bulk of the uppermost lower mantle is radially isotropic in shear wavespeed 16. In order to resolve this paradox, it has been proposed that the dominant

The climate modeling techniques of event attribution enable systematic assessments of the extent that anthropogenic climate change may be altering the probability or magnitude of extreme events. In the consecutive years of 2018, 2019, and 2020, rainfalls caused repeated flooding impacts in the lower Parnaíba River in Northeastern Brazil. We studied the effect that alterations in precipitation resulting from human influences on the climate had on the likelihood of flooding using two ensembles of the HadGEM3-GA6 atmospheric model: one driven by both natural and anthropogenic forcings; and the other driven only by natural atmospheric forcings, with anthropogenic changes removed from sea surface temperatures and sea ice patterns. We performed hydrological modeling to base our assessments on the peak annual streamflow. The change in the likelihood of flooding was expressed in terms of the ratio between probabilities of threshold exceedance estimated for each model ensemble. With uncertainty estimates at the 90% confidence level, the median (5% 95%) probability ratio at the threshold for flooding impacts in the historical period (1982-2013) was 1.12 (0.97 1.26), pointing to a marginal contribution of anthropogenic emissions by about 12%. For the 2018, 2019, and 2020 events, the median (5% 95%) probability ratios at the threshold for flooding impacts were higher at 1.25 (1.07 1.46), 1.27 (1.12 1.445), and 1.37 (1.19 1.59), respectively; indicating that precipitation change driven by anthropogenic emissions has contributed to the increase of likelihood of these events by about 30%. However, there are other intricate hydrometeorological and anthropogenic processes undergoing long-term changes that affect the flood hazard in the lower Parnaíba River. Trend and flood frequency analyses performed on observations showed a nonsignificant long-term reduction of annual peak flow, likely due to decreasing precipitation from natural climate variability and increasing evapotranspiration and flow regulation. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

The climate modeling techniques of event attribution enable systematic assessments of the extent that anthropogenic climate change may be altering the probability or magnitude of extreme events. In the consecutive years of 2018, 2019, and 2020, rainfalls caused repeated flooding impacts in the lower Parnaíba River in Northeastern Brazil. We studied the effect that alterations in precipitation resulting from human influences on the climate had on the likelihood of flooding using two ensembles of the HadGEM3-GA6 atmospheric model: one driven by both natural and anthropogenic forcings; and the other driven only by natural atmospheric forcings, with anthropogenic changes removed from sea surface temperatures and sea ice patterns. We performed hydrological modeling to base our assessments on the peak annual streamflow. The change in the likelihood of flooding was expressed in terms of the ratio between probabilities of threshold exceedance estimated for each model ensemble. With uncertainty estimates at the 90% confidence level, the median (5% 95%) probability ratio at the threshold for flooding impacts in the historical period (1982-2013) was 1.12 (0.97 1.26), pointing to a marginal contribution of anthropogenic emissions by about 12%. For the 2018, 2019, and 2020 events, the median (5% 95%) probability ratios at the threshold for flooding impacts were higher at 1.25 (1.07 1.46), 1.27 (1.12 1.445), and 1.37 (1.19 1.59), respectively; indicating that precipitation change driven by anthropogenic emissions has contributed to the increase of likelihood of these events by about 30%. However, there are other intricate hydrometeorological and anthropogenic processes undergoing long-term changes that affect the flood hazard in the lower Parnaíba River. Trend and flood frequency analyses performed on observations showed a nonsignificant long-term reduction of annual peak flow, likely due to decreasing precipitation from natural climate variability and increasing evapotranspiration and flow regulation. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Hydrocarbon reservoir beds have been delineated using direct hydrocarbon indicator on seismic sections as well as well logs data in X field, Onshore Niger Delta. The research methodology involved horizon interpretation to produce subsurface structure map. Geophysical well log signatures were employed in identifying hydrocarbon bearing sand. The well-to-seismic tie revealed that the reservoir tied directly with hydrocarbon indicator (bright spot) on the seismic sections. The major structure responsible for the hydrocarbon entrapment is anticline. The crest of the anticline from the depth structural map occurs at 3450 metres.

Supercomputing Centers (SCs) have high and variable power demands, which increase the challenges of the Electricity Service Providers (ESPs) with regards to efficient electricity distribution and reliable grid operation. High penetration of renewable energy generation further exacerbates this problem. In order to develop a symbiotic relationship between the SCs and their ESPs and to support effective power management at all levels, it is critical to understand and analyze how the existing relationships were formed and how these are expected to evolve. In this paper, we first present results from a detailed, quantitative survey-based analysis and compare the perspectives of the European grid and SCs to the ones of the United States (US). We then show that contrary to the expectation, SCs in the US are more open toward cooperating and developing demand-management strategies with their ESPs. In order to validate this result and to enable a thorough comparative study, we also conduct a qualitative analysis by interviewing three large-scale, geographically-distributed sites: Oak Ridge National Laboratory (ORNL), Lawrence Livermore National Laboratory (LLNL), and the Leibniz Supercomputing Center (LRZ). We conclude that perspectives on demand management are dependent on the electricity market and pricing in the geographical region and on the degree of control that a particular SC has in terms of power-purchase negotiation.

Recent seismic studies indicate the presence of seismic anisotropy near subducted slabs in the transition zone and uppermost lower mantle (mid‐mantle). In this study, we investigate the origin of radial anisotropy in the mid‐mantle using 3‐D geodynamic subduction models combined with mantle fabric simulations. These calculations are compared with seismic tomography images to constrain the range of possible causes of the observed anisotropy. We consider three subduction scenarios: (i) slab stagnation at the bottom of the transition zone; (ii) slab trapped in the uppermost lower mantle; and (iii) slab penetration into the deep lower mantle. For each scenario, we consider a range of parameters, including several slip systems of bridgmanite and its grain‐boundary mobility. Modeling of lattice‐preferred orientation shows that the upper transition zone is characterized by fast‐SV radial anisotropy anomalies up to −1.5%. For the stagnating and trapped slab scenarios, the uppermost lower ma...

The risk of floods has increased in South Asia due to high vulnerability and exposure. The August 2022 Pakistan flood shows a glimpse of the enormity and devastation that can further rise under the warming climate. The deluge caused by the Pakistan floods in 2022, which badly hit the country's southern provinces, is incomparable to any recent events in terms of the vast spatial and temporal scale. The 2022 Pakistan flood ranked third in human mortality, while this was the top event that displaced about 32 million people. Using observations and climate projections, we examine the causes and implications of the August 2022 flood in Pakistan. Multiday (˜15 days) extreme precipitation on wet antecedent soil moisture conditions was the primary driver of the flood in August 2022. The extreme precipitation in August was caused by two atmospheric rivers that passed over southern Pakistan. Streamflow simulations from the multiple hydrological models show that extreme precipitation was the primary driver of floods as several stations in the flood-affected regions experienced anomalously higher flow than the stations located upstream. The frequency of similar multi-day extreme precipitation events is projected to rise four-fold under the high emission scenario. The 2022 Pakistan flood highlights the adaptation challenges that South Asia is facing along with the substantial need for climate mitigation to reduce the risk of such events in the future.

The Niger Delta, where oil and gas are predominantly trapped in sandstones and unconsolidated sands in the Agbada formation, ranked among the world's major hydrocarbon provinces. The traps, structure and stratigraphic, could be very subtle and complex and are therefore, difficult to map accurately. The degree of reliability and precision of the mapping can be greatly enhanced by integrating seismic data with well logs commonly used independently in hydrocarbon exploration and exploitation studies. In this paper, seismic data were integrated with well logs to define the subsurface geometry, stratigraphy and hydrocarbon trapping potential of Emi-field, off shore Niger Delta. Lithologic units were identified on the logs and correlated across the wells. The stratigraphic cross-sections produced show a general lateral continuity of the lithologic units across the field. Seismic-to-well ties revealed that, high amplitude reflection events correspond to sand units, whereas, low amplitude reflection events correspond to shale units. Four horizons, H 1 , H 2 , H 3 and H 4 were mapped and structure contour maps produced for each of the horizons. Closures considered as good hydrocarbon prospects were identified and delineated. Stratigraphic plays such as pinch-outs, unconformities, sand lenses and channels are also suspected. The integration of seismic data with well logs proved to be a useful tool in structural and stratigraphic mapping and in predicting lateral and vertical variations in the lithologic units.

x actual average yield). However, if the rising trends in minimum and maximum temperatures persist, there is a high possibility that the yield losses will become more severe in the future. Next, the identification of flood and drought-prone areas is executed. The inundated areas at 10, 25, 50, and 100-year return period are obtained from an integrated hydrologic (SWAT) and hydraulic (HEC-RAS) model. The flooded areas are larger on the left bank than the right and that the flood depths vary from 0-4 m. About 60% of the floodplain inundation is less than 1 m and mostly found at the upstream and central areas of the river. The flat terrains make flooding duration last long, causing damage to crop growth and yields, particularly rice, which occupies a majority of the area and mostly locates on the river banks. Drought-prone areas are detected by using the proposed comprehensive drought risk assessment scheme that incorporates hazard, exposure, and vulnerability. The hazard is estimated from water deficits calculated with respect to rice water requirement. Exposure is based on population and rice field characteristics, while other physical and socioeconomic factors and coping capacity are used in the estimation of vulnerability. The findings demonstrate that drought hazard is most critical in October, which can reduce rice yields significantly. Rice fields in the central part are more exposed to droughts than in other areas. Extensive land is under high and moderate vulnerability. The higher drought risks emerge in October and November and decrease from north to south. After flood and drought problems are identified, a coping capacity of existing and ongoing water resources development projects are evaluated. The total storage capacity of those projects is sufficient to cope with both hazards, but the performance is inefficient and ineffective. Thus, several pieces of advice are provided to improve the performance of in-situ measures. Moreover, other measures are proposed to complement the existing measures and make the storage system more flexibility. The suggested measures are practicable, applicable, economical, and less environmental impacts. They have the potential to sustainably solve both floods and droughts in order to enhance rice production in the basin. This study provides all dimensions associated with floods and droughts, their impacts on rice yields, and mitigation measures to tackle both hazards simultaneously and sustainably. The achievement over the two climate extremes will ensure adequate food availability and alleviate poverty in the basin. Furthermore, the study shows that a holistic approach to simultaneously solving both problems is efficiency as all drops of water are utilized to benefit agriculture, the primary sector that feeds a growing population. 1 General introduction 1.1 Floods and droughts 1.1.1 Flooding 1.1.2 Drought 1.2 Impacts on agriculture 1.3 Research gaps 1.4 Selection of the study area and scope of the study 1.5 Research objectives 1.6 Outline of the thesis References 2 Chapter 1 1.1 Floods and droughts Floods and droughts are the two main meteorological catastrophes. Flooding occurs the most (33%), whereas droughts are less frequent (5%-Table 1-1), but cause more fatal impacts in terms of the number of the death toll. Combined, the hazards account for 80% of the total number of people affected by natural disasters (Table 1-2). Furthermore, they have created enormous environmental, social, and economic impacts, such as degraded wetland areas, diminished natural biodiversity, destroyed agricultural land and industrial facilities, and high economic costs. It is expected that climate change effects (i.e., more intense rainfall, increasing seawater levels, etc.) will exacerbate flood occurrences and impacts in the future (

zone de subduction des Nouvelles-Hébrides par les diverses techniques géophysiques permet de répondre, au 'moins partiellement, aux problèmes géodynamiques qui se posent dans cette région. MOUVEMENT DES PLAQUES Dans les modèles globaux (MORGAN, 1968 ; LE PICHON, 1968), on considère les mouvements relatifs d'un petit nombre de plaques sur l'ensemble du globe. On détermine pour chaque couple de plaques un pôle de rotation et une vitesse qui définissent le mouvement relatif des deux plaques. La vitesse de convergence des plaques Indo-australienne et Pacifique ainsi déterminée est, au niveau du

This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit:

A new pre-exascale computer cluster has been designed to foster scientific progress and competitive innovation across European research systems, it is called LEONARDO. This paper describes the general architecture of the system and focuses on the technologies adopted for its GPU-accelerated partition. High density processing elements, fast data movement capabilities and mature software stack collections allow the machine to run intensive workloads in a flexible and scalable way. Scientific applications from traditional High Performance Computing (HPC) as well as emerging Artificial Intelligence (AI) domains can benefit from this large apparatus in terms of time and energy to solution.

Reference Evapotranspiration (ETo) and soil moisture deficit (SMD) are vital for understanding the hydrological processes, particularly in the context of sustainable water use efficiency in the globe. Precise estimation of ETo and SMD are required for developing appropriate forecasting systems, in hydrological modeling and also in precision agriculture. In this study, the surface temperature downscaled from Weather Research and Forecasting (WRF) model is used to estimate ETo using the boundary conditions that are provided by the European Center for Medium Range Weather Forecast (ECMWF). In order to understand the performance, the Hamon's method is employed to estimate the ETo using the temperature from meteorological station and WRF derived variables. After estimating the ETo, a range of linear and non-linear models is utilized to retrieve SMD. The performance statistics such as RMSE, %Bias, and Nash Sutcliffe Efficiency (NSE) indicates that the exponential model (RMSE = 0.226; %Bias = −0.077; NSE = 0.616) is efficient for SMD estimation by using the Observed ETo in comparison to the other linear and non-linear models (RMSE range = 0.019-0.667; %Bias range = 2.821-6.894; NSE = 0.013-0.419) used in this study. On the other hand, in the scenario where SMD is estimated using WRF downscaled meteorological variables based ETo, the linear model is found promising (RMSE = 0.017; %Bias = 5.280; NSE = 0.448) as compared to the non-linear models (RMSE range = 0.022-0.707; %Bias range = −0.207-−6.088; NSE range = 0.013-0.149). Our findings also suggest that all the models are performing better during the growing season (RMSE range = 0.024-0.025; %Bias range = −4.982-−3.431; r = 0.245-0.281) than the non−growing season (RMSE range = 0.011-0.12; %Bias range = 33.073-32.701; r = 0.161-0.244) for SMD estimation.

This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit:

The snowfall prediction is important in winter and early spring because snowy conditions generate enormous economic damages. However, there is a lack of previous studies dealing with snow prediction, especially using land surface models (LSMs). Numerical weather prediction models directly interpret the snowfall events, whereas the LSMs evaluate the snow cover fraction, snow albedo, and snow depth through interaction with atmospheric conditions. When the initially-developed empirical parameters are local or inadequate, we need to optimize the parameter sets for a certain region. In this study, we seek for the optimal parameter values in the snow-related processes-snow cover fraction, snow albedo, and snow depth-of the Noah LSM, for South Korea, using the micro-genetic algorithm and the in-situ surface observations and remotely-sensed satellite data. Snow data from surface observation stations representing five land cover types-deciduous broadleaf forest, mixed forest, woody savanna, cropland, and urban and built-up lands-are used to optimize five snow-related parameters that calculate the snow cover fraction, maximum snow albedo of fresh snow, and the fresh snow density associated with the snow depth. Another parameter, reflecting the dependence of snow cover fraction on the land cover types, is also optimized. Optimization of these six snow-related parameters has led to improvement in the root-mean squared errors by 17.0 %, 8.2 %, and 5.6 % on snow depth, snow cover fraction, and snow albedo, respectively. In terms of the mean bias, the underestimation problems of snow depth and overestimation problems of snow albedo have been alleviated through optimization of parameters calculating the fresh snow by about 45.1 % and 32.6 %, respectively. 1 Introduction Land surface models (LSMs) act as the lower boundary conditions for regional numerical weather prediction (NWP) and climate models, to which they provide the surface fluxes (Ek et al., 2003). However, LSMs include inevitable uncertainties due to insufficient knowledge of surface layer processes and characteristics; for instance, unreasonable representation of the spatiotemporal surface heterogeneity and the inaccuracy of the parameters based on empirical relations contribute to the uncertainties 1

The Superior Province of the Canadian Shield is the largest contiguous region of the Archean crust. A combination of data from multiple experiments is used to obtain shear wave splitting parameters and a three-dimensional tomographic velocity model beneath a large portion of the Superior, corresponding approximately to the province of Ontario. Shear wave splits are obtained at 24 sites across the Superior, displaying strong (averaging 1.34 s) ENE-WSW splitting at stations west of 86°W and weaker (0.67 s) E-W splitting in the east. The fast direction is subparallel to both absolute plate motion and tectonic belt boundaries. The recovered tomographic velocity model shows a major boundary oriented NNW-SSE, separating high velocities in the western Superior (WS) from low velocities in the east and coinciding with the divide between weak and strong shear wave splits. Other features include a 200-km-thick low-velocity anomaly corresponding to the Nipigon Embayment, a 1.0-Ga failed-rift branch; and a linear low-velocity anomaly in the east, attributed to the Great Meteor hot spot track. The Nipigon anomaly, in the western portion of the model, is probably in situ, while the Great Meteor track is displaced from crustal features associated with the hot spot. We interpret this displacement as evidence that the eastern lithosphere has been deformed by basal drag, while the western lithosphere has remained stable, and propose that the east-west lithospheric boundary we have detected represents a change in mechanical properties, between stronger, higher velocity western material with consistent anisotropic fabric, and weaker eastern material with more variable fabric.

Seismic attributes for enhanced structural and stratigraphic interpretation of Fuba Field, Onshore Niger Delta, Nigeria using Well-log and 3D Seismic data are here presented. Well-to-Seismic ties, faults and horizon mapping, time-surface generation, depth conversion and seismic attributes generation were carried out using Petrel software. The structural interpretation of seismic data reveal highly synthetic and antithetic faults which are in line with faults trends identified in the Niger Delta. Of the 29 interpreted faults, only synthetic and antithetic faults are regional, running from the top to bottom across the field. These faults play significant roles in trap formation at the upper, middle and lower sections of the field. Two distinct horizons were mapped. Fault and horizon interpretation reveal closures which are collapsed crestal structures bounded by these two major faults. The depth structure maps reveal anticlinal faults. Reservoirs are found at a shallower depth from 6500 to 7500ft and at a deeper depth ranging from 11500 to 13000ft. The synthetic and antithetic faults act as good traps for the hydrocarbon accumulation in the study area. The variance and chaos values range from 0.0 to 1.0. The dip magnitude and azimuth values range from 0 to 90 degrees and 0 to 360 degrees. The variance edge, chaos, dip magnitude and azimuth analysis were used to delineate the prominent and subtle faults in the area. The results of spectral decomposition at a frequency of 12-35Hz indicates areas of low frequency and high amplitude associated with known hydrocarbon zones, the presence of channels, lobes and small scale faults in the field. The result of the seismic attribute analysis has shown that the Fuba field has good hydrocarbon prospects.

Complexly faulted subsurface configuration is capable of causing erroneous deductions in the absence of a well packaged interpretation approach and workflow for an oilfield exploration programme, thus a well prepared analysis saddled on the use and integration of sufficient data is indispensable to the unravelling of complex field subsurface structure as the search for oil and gas progresses into deeper waters. S uite of signatures from wireline logs and seismic volume was employed to gain more insight into the complexities of the hydrocarbon hosting units within and outside the vicinity of well control in the X-field Niger Delta. Horizons and fault interpretation were carried out to produce subsurface structure maps. Amplitudes of the horizons mapped were extracted and were used to study the distri bution of the hydrocarbon sand. Three hydrocarbon bearing reservoirs were delineated within the study interval, namely: ROJ A, ROJ C and ROJ D. Well to seismic tie revealed that these reservoirs tied direct hydrocarbon indicators (bright spots) on the vertical sections. The structure maps produced revealed a series of NW-S E and E-W trending growth faults and fault echelons, most of which dip to the south. Fault assisted closure s were revealed at the southern part of the field, which correspond to the crest of roll over structures and possibly served as the trapping mechanism for the reservoirs. The reflection amplitude of the studied horizons shows a fine network of anomalies that can be correlated to the prediction of the lateral distribution of the hydrocarbon sand. The conclusion of the study was that the western part of horizon ROJ A is a highly prospective area as bright spots were observed in the region. Also in the adjacent southern direction of this horizon, hydrocarbon accumulations have been confirmed from wells. These gas sands are possibly trapped in anticlinal closures located in the same area. On the other hand, the results from the study of horizon ROJ C suggest de velopment opportunities in the southern area. High amplitude gas sands are seen to spread to the south and stratigraphy was assumed to play a major role in hydrocarbon migration. The study over horizon ROJ D reveal likely geologic features like regional sand pinch outs and channels in the southern part of the field. S pectral decomposition interpretation was suggested to be used further in improving the delineation of the thin reservoir sand bodies and for better outlining of their geometries but was not available on the workstation used. The study has shown the feasibility of integrating structural interpretation and instantaneous amplitude in prospect identification and reservoir prediction.

Seismic anisotropy provides key information to map the trajectories of mantle flow and understand the evolution of our planet. While the presence of anisotropy in the uppermost mantle is well-established, the existence and nature of anisotropy in the transition zone and uppermost lower mantle are still debated. Here we use 3-D global seismic tomography images based on a large data set sensitive to this region to show the ubiquitous presence of anisotropy in the lower mantle beneath subduction zones. Whereas above the 660-km seismic discontinuity slabs are associated with faster SV anomalies up to about 3%, in the lower mantle faster SH anomalies of about 2% persist near slabs down to about 1,000-1,200 km. These observations are consistent with 3-D 1 numerical models of deformation from subducting slabs and the associated lattice preferred orientation of bridgmanite produced in the dislocation creep regime in areas subjected to high stresses. This study provides evidence that dislocation creep may be active in the Earth's lower mantle, providing new constraints on the debated nature of deformation in this key but inaccessible component of the deep Earth. The Earth's upper and lower mantle have quite distinct physical properties, with the characteristics of material exchange between them being a long-debated issue. Progress in global seismic tomography in the 1990s 1,2 showed that the upper and lower mantle interact mainly via subducting slabs and mantle plumes, albeit subject to the presence of strong resistance along the upper-lower mantle boundary at ∼660 km depth. More recently, enhanced tomography images showed that amongst the slabs that penetrate into the lower mantle, many of them stagnate down to about ∼1,000 km depth 3. Conversely, mantle plumes rising from the deep lower mantle seem to deflect laterally when they reach this region 4. However, the uppermost lower mantle, located at depths of ∼660-1,000 km, remains an enigmatic part of the Earth. It has been suggested that compositional layering 5,6 or a viscosity increase 7,8 may cause flow stagnation in this region, but its rheology and role in mantle convection are poorly understood. The stagnation of subducting slabs at ∼660 km depth and their penetration into the lower mantle lead to intense strain and deformation around the slabs, which in turn can align mineral aggregates. Since the most abundant lower mantle mineral (bridgmanite) is anisotropic, observable seismic anisotropy should develop when considering a dislocation creep deformation mechanism 9,10,11. However, apart from the D" region in the lowermost mantle 12 , the presence of seismic anisotropy in the lower mantle is uncertain and debated 13,14,15 , with most previous seismological models suggesting that the bulk of the uppermost lower mantle is radially isotropic in shear wavespeed 16. In order to resolve this paradox, it has been proposed that the dominant

The EU Center of Excellence for Exascale in Solid Earth (ChEESE) develops exascale transition capabilities in the domain of Solid Earth, an area of geophysics rich in computational challenges embracing different approaches to exascale (capability, capacity, and urgent computing). The first implementation phase of the project (ChEESE-1P; 2018-2022) addressed scientific and technical computational challenges in seismology, tsunami science, volcanology, and magnetohydrodynamics, in order to understand the phenomena, anticipate the impact of natural disasters, and contribute to risk management. The project initiated the optimisation of 10 community flagship codes for the upcoming exascale systems and implemented 12 Pilot Demonstrators that combine the flagship codes with dedicated workflows in order to address the underlying capability and capacity computational challenges. Pilot Demonstrators reaching more mature Technology Readiness Levels (TRLs) were further enabled in operational service environments on critical aspects of geohazards such as long-term and short-term probabilistic hazard assessment, urgent computing, and early warning and probabilistic forecasting. Partnership and service co-design with members of the project Industry and User Board (IUB) leveraged the uptake of results across multiple research institutions, academia, industry, and public governance bodies (e.g. civil protection agencies). This article summarises the implementation strategy and the results from ChEESE-1P, outlining also the underpinning concepts and the roadmap for the ongoing second project implementation phase (ChEESE-2P; 2023-2026).

Integrating seismic amplitudes and spectral attribute analysis has successfully mapped, validated and characterised hydrocarbon-saturated channel sands by high-amplitude low-frequency anomaly. The aim of the study was targeted at using these novel geophysical tools to improve characterisation of tertiary clastic reservoir in the field. These attributes were extracted along H4 seismic horizon and analysed independently for structure, lithology and hydrocarbon saturation. The result of the analysis shows that both attributes complimented each other in mapping the hydrocarbon-saturated reservoir channel sands. However, the spectral attributes in combination with spectral-based Red, Blue and Green (RGB) colour blending attribute map reveal finer and subtle details of the channel structure and stratigraphy which hitherto were not apparent in the seismic amplitude maps. The channel sands trend NE–SW, broadening towards the southwest and bounded by major growth faults to the northeast and ...

Land use/cover change (LUCC) has taken place since the 1990s in central Taiwan; however, its impacts on the local and regional hydroclimatology are not understood thoroughly. This study is grounded in a numerical experiment using the Weather Research and Forecasting (WRF) model and statistical assessments of continuous land cover and gridded precipitation data derived for central Taiwan. We incorporate survey-based land use data in 1995 and 2007 in driving WRF to simulate selective non-rainy and rainy (dry and wet) cases under weak synoptic forcings in July and August (JA). The two land-use conditions reveal changes in simulation fields on account of increased urban and built-up lands. Results averaged over the dry cases show increased (diminished) sensible heat fluxes and 2 m temperatures (latent heat fluxes and 2 m specific humidity) in 2007 compared to that in 1995. The wet-case simulation further identifies intensified precipitation over the downwind areas of urban and built-up ...

In Sumatra in Indonesia, large-scale plantations of oil palm and acacia trees have caused 50 % reduction of natural forests in the 25 years between 1985 to 2009. Both climate and land cover changes may impact on regional water cycle, which potentially leads to increase the risk of flood and drought. Therefore, hydrologic process understandings and their representations by hydrological models are important steps for achieving adequate water resources and water-related disaster management. Among various hydrological processes, rainfallrunoff processes in humid tropics, which is typically characterized by flow in a deep soil layer, have been poorly understood. This study conducts field investigations and modeling to simulate rainfall-runoff and flood inundation processes at the river basin scale in the Batanghari River basin in Sumatra, Indonesia. By reflecting such conditions in the model, it conducts a long-term hydrologic simulation with climate change projected based on MRI-AGCM (2...

Landslides are one of the most disastrous natural hazards that frequently occur in Indonesia. In 2017, Balai Sabo developed an Indonesia Landslide Early Warning System (ILEWS) by utilizing a single rainfall threshold for an entire nation, leading to inaccuracy in landslide predictions. The study aimed to improve the accuracy of the system by updating the rainfall threshold. We analyzed 420 landslide events in Java with the 1-day and 3-day effective antecedent rainfall for each landslide event. Rainfall data were obtained from the Global Precipitation Measurement (GPM), which is also used in the ILEWS. We propose four methods to derive the thresholds: the first is the existing threshold applied in the Balai Sabo ILEWS, the second and third use the average and minimum values of rainfall that trigger landslides, respectively, and the fourth uses the minimum value of rainfall that induces major landslides. We used receiver operating characteristic (ROC) analysis to evaluate the predicta...

Hydro-meteorological drought was assessed with respect to climate change over an estuary catchment in Central Vietnam, an area whose economy is dependent on agriculture, especially rice production. The Vu Gia-Thu Bon river basin is prone to flooding and drought. The fully-distributed hydrological model MIKE SHE was used to simulate river flow over the study region for the period 1991-2010. Meteorological and hydrological drought were assessed using the Standardized Precipitation Index (SPI) and the Standardized Runoff Index (SRI). The future climate was studied using the regional climate model Weather Research and Forecasting by dynamically downscaling an ensemble of three global climate models-CCSM3.0, ECHAM5 and MIROC-medium resolution-over current (1961-1990) and future climates (2011-2040), under the A2 emissions scenario. The results suggest that, despite hotter and wetter future climate, the area is likely to suffer more from severe and extreme droughts, increasing about 100% in the median range for drought characteristics. Thus, there is a need for proper adaptation and planning for water resources management in this region.

Accurate and timely rain prediction is crucial for decision making and is also a challenging task. This paper presents a solution which won the 2 nd prize in the Weather4cast 2022 NeurIPS competition using 3D U-Nets and EarthFormers for 8-hour probabilistic rain prediction based on multi-band satellite images. The spatial context effect of the input satellite image has been deeply explored and optimal context range has been found. Based on the imbalanced rain distribution, we trained multiple models with different loss functions. To further improve the model performance, multi-model ensemble and threshold optimization were used to produce the final probabilistic rain prediction. Experiment results and leaderboard scores demonstrate that optimal spatial context, combined loss function, multi-model ensemble, and threshold optimization all provide modest model gain. A permutation test was used to analyze the effect of each satellite band on rain prediction, and results show that satellite bands signifying cloudtop phase (8.7 µm) and cloud-top height (10.8 and 13.4 µm) are the best predictors for rain prediction.

The rapid development of settlements and sediment deposition has increasingly narrowed the drainage in the Code River. This condition causes floods and wider distribution of the affected areas. This research aims to estimate the maximum amount of rain, predict the probability of flood, and predict flood-prone areas in the Code River. Data were collected by observation, remote sensing image interpretations, literature studies, and documentation. Data analysis was performed using Log Pearson Type III for design rainfall analysis, Weibull formula for flood probability analysis, and rational method for planning maximum discharge analysis. Flood modeling is carried out by the iteration method. The results show: (1) the maximum amount of rain based on the calculated design rainfall with a return period of 5 to 40 years is R5 = 106.83 mm, R10 = 116.67 mm, R20 = 127.30 mm, R40 = 134.25 mm, (2) the probability of flood that is predicted from the maximum discharge caused by the design rainfal...

In the past decade, the Abitibi-Grenville Lithoprobe transect has been the site of numerous geological and geophysical surveys oriented towards understanding the lithospheric evolution of the southeastern Superior and adjoining Grenville provinces. Among the different geophysical methods that have been employed, earthquake seismology provides the widest range of information on the deep structures of the upper mantle. This paper presents a review of studies, both complete and ongoing, involving teleseismic datasets that were collected in 1994 and 1996 along the transect. A complete shear-wave splitting analysis has been performed on the 1994 dataset as part of a comparative study on electrical and seismic anisotropies. Results suggest a correlation between the two anisotropies (supported by xenolith data) and favour a lithospheric origin for the seismic anisotropy. The two anisotropies are believed to represent the fossilized remnants of Archean strain fields in the lithospheric roots of the Canadian Shield. Preliminary splitting results for the 1996 experiment suggest that the S-wave azimuthal anisotropy may be depth dependent and laterally varying. Ongoing receiver function analysis and traveltime inversion studies provide velocity models of the crust and upper mantle beneath the study area. Preliminary receiver function results reveal the presence of an S-velocity increase at-90-100 km depth which appears to be laterally continuous over 200 km. Traveltime inversion models indicate the presence of an elongate, low-velocity anomaly beneath the southern portion of the 1996 array which strikes obliquely to major geological structures at the surface (e.g., Grenville Front). Preliminary interpretation relates this anomaly to the same process (e.g., fixed mantle plume, continental rifting) responsible for the emplacement of the Monteregian Hills igneous province. Résumé : Au cours de la dernière décennie, de nombreuses campagnes géologiques et géophysiques ont été effectuées le long de la traverse Abitibi-Grenville du projet Lithoprobe, dans le but de comprendre l'évolution lithosphérique de la

Most studies of thermally induced cracking in rocks have focused on the generation of cracks formed during heating and thermal expansion. Both the nature and the mechanism of crack formation during cooling are hypothesized to be different from those formed during heating. We present in situ acoustic emission data recorded as a proxy for crack damage evolution in a series of heating and cooling experiments on samples of basalt and dacite. Results show that both the rate and the energy of acoustic emission are consistently much higher during cooling than during heating. Seismic velocity comparisons and crack morphology analysis of our heated and cooled samples support the contemporaneous acoustic emission data and also indicate that thermal cracking is largely isotropic. These new data are important for assessing the contribution of cooling-induced damage within volcanic structures and layers such as dikes, sills, and lava flows. When subjected to a change in temperature a rock mass will fracture when the thermal stresses generated by expansion or contraction of individual grains in contact with other grains reach the tensile or shear strength of the material. In the absence of thermal shock or high thermal gradients, thermal stresses are generated by two main mechanisms: (1) mismatch in thermal expansion coefficients between different minerals and BROWNING ET AL.

The source kitchen of a petroleum system is that part of the pod of active source rock which is mature and generates the petroleum that charges the reservoir rock. The location of the source kitchen of a petroleum system is vital to the explorationist, its knowledge fosters the prediction of migratory pathways and the migratory losses prior to present times, also estimates potential volume of accumulation. Hither to, mapping of the petroleum basins was based on total organic carbon (TOC), hydrogen index (HI) signatures and maturity history of the source rock and has been used as the basis to suggest locations of petroleum kitchens. In contemporary times, 4D seismic or 3D time lapse geochemistry had been used to suggest location of source kitchen. However, settled is the concept of lateral maturity gradients, implying that within reservoir scales of a kilometer to tens of kilometers, regional petroleum emplacement direction could be deduced from subtle changes in maturity of successive charges of petroleum into the reservoir. In this study, the sterane isomerization ratio (20S/20S ? 20R aaaC 29) was used to determine the maturities of the hydrocarbons from various wells in the Kolo Creek and the Nembe Creek reservoirs. Subtle increases in maturities were observed to be in a NE-SW direction for the Kolo Creek reservoir and in a NW-SE direction for the Nembe Creek reservoir. The direction of increasing maturities relative to the location of the reservoirs could be extrapolated for both reservoirs towards offshore Gulf of Guinea; this is invariably the direction of location of the source kitchen for the Niger Delta oils.

Establishing the conditions and dynamics of pre-eruptive magma storage and transfer within transient transcrustal storage networks is a major focus of quantitative volcanic petrology. In Iceland, the behaviour, conditions and timescales of magmatic processes within on-rift plumbing systems are increasingly well constrained. However, relatively little is known about magma storage and transfer in off-rift zones, despite off-rift volcanoes being able to generate hazardous explosive eruptions after centuries or millennia of dormancy (e.g. 2010 AD Eyjafjallajökull; 1362 AD Öræfajökull; 3.0 ka, 4.2 ka and 1104 AD Hekla). We present a combined geochemical and geothermobarometric study of magma storage and transfer recorded in the products of the postglacial Búðahraun (∼5.0–8.0 ka) and Berserkjahraun (∼4.0 ka) eruptions within the Snæfellsnes volcanic zone. The eruption products contain diverse and compositionally heterogeneous macrocryst cargoes recording complex petrogenetic histories of ...

Les phénomènes sismiques ne représentent alors qu'une expression partielle de la déformation terrestre. Néanmoins, dès l'Antiquité, ils ont contribué à susciter l'intérêt des scientifiques pour l'intérieur de notre planète. Durant toute cette période, c'est la vision de la structure interne proposée par Aristote qui domine. Celui-ci suggère que notre planète est entièrement constituée de terre et de roches et présente des cavités et canaux dans sa partie superficielle ; le vent s'engouffrant dans ces cavités serait Le modèle PREM (Preliminary Reference Earth Model) de Dziewoński et Anderson (1981), présenté en Figure 5, en est certainement l'exemple le plus connu. En plus de l'évolution avec la profondeur des vitesses sismiques P et S déterminées à partir de l'étude des ondes de volume et de surface, PREM fournit également l'évolution de la densité-contrainte grâce à l'étude des oscillations libres de la Terre. Les couches identifiées par des lettres par Jeffreys et Bullen sont alors associées dans les modèles plus récents à la croûte, le manteau supérieur, la zone de transition du manteau, le manteau inférieur, le Plan du manuscrit Depuis ses débuts et encore aujourd'hui, la sismologie est une science en perpétuelle évolution. Bien qu'elle ne fournisse qu'une image instantanée de l'intérieur de notre planète, c'est une méthode capable et les cercles représentent respectivement les stations permanentes et temporaires. Modifiée d'après Hetényi et al. (2018). 7.2 Tomographique 3-D anisotrope de la croûte et du manteau supérieur européens à partir de données de bruit sismique Cette section reprend un article à soumettre prochainement à Geophysical Journal International. Cet article reprend la présentation de l'origine des données et les différentes méthodes abordées dans les Chapitres 4 à 6. Il permet de présenter notre modèle 3-D de vitesse et d'anisotropie radiale d'ondes S ainsi que les interprétations associées.