Preprints
There are 7999 Preprints listed.
Two-fluid single-column modelling of Rayleigh-Bénard convection as a step towards multi-fluid modelling of atmospheric convection
Published: 2021-06-17
Subjects: Atmospheric Sciences
Multi-fluid models have recently been proposed as an approach to improving the representation of convection in weather and climate models. This is an attractive framework as it is fundamentally dynamical, removing some of the assumptions of mass-flux convection schemes which are invalid at current model resolutions. However, it is still not understood how best to close the multi-fluid equations [...]
Fluid invasion dynamics in porous media with complex wettability and connectivity
Published: 2021-06-17
Subjects: Chemical Engineering, Complex Fluids, Earth Sciences, Fluid Dynamics, Hydrology, Materials Science and Engineering, Other Materials Science and Engineering, Petroleum Engineering, Transport Phenomena
Multiphase flow is important for many natural and engineered processes in subsurface geoscience. Pore-scale multiphase flow dynamics are commonly characterized by an average balance of driving forces. However, significant local variability in this balance may exist inside natural, heterogeneous porous materials, such as rocks and soils. Here, we investigate multiphase flow in heterogeneous rocks [...]
Projecting armed conflict risk in Africa towards 2050 along the Shared Socio-economic Pathways: a machine learning approach
Published: 2021-06-22
Subjects: Environmental Sciences
In the past decade, several efforts have been made to project armed conflict risk into the future. One arising technique is the use of machine-learning (ML) models. In this study we explore its opportunities to project sub-national armed conflict risk for three shared socio-economic pathway (SSP) scenarios and three Representative Concentration Pathways (RCPs) by 2040-2050 in Africa, using the [...]
Rotational Ground Motion Measurements for Regional Seismic Moment Tensors: a Review
Published: 2021-06-18
Subjects: Physical Sciences and Mathematics
Seismic moment tensors are an important tool in geosciences on all spatial scales and for a broad range of applications. The basic underlying theory is established since decades. However, various factors influence the reliability of the inversion result, several of them are mutually dependent. Hence, a reliable retrieval of seismic moment tensors is still hampered in many cases, especially at [...]
Characteristics of landslide path dependency revealed through multiple resolution landslide inventories in the Nepal Himalaya
Published: 2021-06-18
Subjects: Earth Sciences, Geology, Geomorphology
Recent research in Umbria, Italy, has shown that landslide susceptibility is controlled by a process called path-dependency, which describes how past landslides control the locations of future landslides. To date, landslide path-dependency has only been characterised in Italy. This raises the question of whether this process occurs in other geomorphic settings, and thus whether path-dependency [...]
Geodynamic, geodetic, and seismic constraints favour deflated and dense-cored LLVPs
Published: 2021-06-18
Subjects: Cosmochemistry, Earth Sciences, Geochemistry, Geophysics and Seismology, Mineral Physics, Physical Sciences and Mathematics
Two continent-sized features in the deep mantle, the large low-velocity provinces (LLVPs), influence Earth's supercontinent cycles, mantle plume generation, and its geochemical budget. Seismological advances have steadily improved LLVP imaging, but several fundamental questions remain unanswered, including: What is their vertical extent? And, are they purely thermal anomalies, or are they also [...]
Bayesian population correlation: A probabilistic approach to inferring and comparing population distributions for detrital zircon ages
Published: 2021-06-18
Subjects: Geochemistry, Probability, Statistical Methodology, Tectonics and Structure
Populations of detrital zircons are shaped by geologic factors such as sediment transport, erosion mechanisms, and the zircon fertility of source areas. Zircon U-Pb age datasets are influenced both by these geologic factors and by the statistical effects of sampling. Such statistical effects introduce significant uncertainty into the inference of parent population age distributions from detrital [...]
Modeling P waves in seismic noise correlations: Advancing fault monitoring using train traffic sources
Published: 2021-06-19
Subjects: Applied Mathematics, Earth Sciences, Geophysics and Seismology, Physics
The theory of Green's function retrieval essentially requires homogeneously distributed noise sources. Even though these conditions are not fulfilled in nature, low-frequency (<1 Hz) surface waves generated by ocean-crust interactions have been used successfully to image the crust with unprecedented spatial resolution. In contrast to low-frequency surface waves, high-frequency (>1 Hz) body waves [...]
Paleomagnetism from multi-orogenic terranes is "not a simple game": Pyrenees' Paleozoic warning
Published: 2021-06-21
Subjects: Geophysics and Seismology, Tectonics and Structure
Paleomagnetism is a versatile tool in the Earth sciences: it provides critical input to geological time scales and plate tectonic reconstructions. Despite its undeniable perks, paleomagnetism is not without complications. Remagnetizations overprinting the original magnetic signature of rocks are frequent, especially in orogens which tend to be the areas with better rock exposure. Unraveling the [...]
Colonial history and global economics distort our understanding of deep-time biodiversity
Published: 2021-06-24
Subjects: Earth Sciences, Ecology and Evolutionary Biology, Life Sciences, Paleobiology, Paleontology, Physical Sciences and Mathematics
Sampling variations in the fossil record distort estimates of past biodiversity. However, compilations of global fossil occurrences used in these analyses not only reflect the geological and spatial aspects of the fossil record, but also the historical collation of these data. Here, we demonstrate how the legacy of colonialism as well as socio-economic factors such as wealth, education and [...]
Skillful decadal prediction of unforced southern European summer temperature variations
Published: 2021-06-25
Subjects: Physical Sciences and Mathematics
We assess the capability of decadal prediction simulations from the Coupled Model Intercomparison Project phase 6 (CMIP6) archive to predict European summer temperature during the period 1970-2014. Using a multi-model ensemble average, we show that Southern European (SEU) summer temperatures are highly predictable for up to 10 years in CMIP6. Much of this predictive skill, is related to the [...]
Mass loss of the Antarctic ice sheet until the year 3000 under a sustained late-21st-century climate
Published: 2021-06-23
Subjects: Physical Sciences and Mathematics
Ice-sheet simulations of Antarctica extending to the year 3000 are analysed to investigate the long-term impacts of 21st century warming. Climate projections are used as forcing until 2100 and afterwards no climate trend is applied. Fourteen experiments are for the “unabated warming” pathway, and three are for the “reduced emissions” pathway. For the unabated warming path simulations, West [...]
A fully-coupled 3D model of a large Greenlandic outlet glacier with evolving subglacial hydrology, frontal plume melting and calving
Published: 2021-06-25
Subjects: Glaciology
We present the first fully coupled 3D full-Stokes model of a tidewater glacier, incorporating ice flow, subglacial hydrology, plume-induced frontal melting and calving. We apply the model to Store Glacier (Sermeq Kujalleq) in west Greenland to simulate a year of high melt (2012) and one of low melt (2017). In terms of modelled hydrology, we find perennial channels extending 5 km inland from the [...]
Regional SST and SLP conditions related to tornado 'outbreak' environments 15 days later
Published: 2021-06-25
Subjects: Physical Sciences and Mathematics
Global climate features are known to influence tornado frequency in the U.S., but more work needs to focus on understanding the extent to which climate variables contribute to increases in CAPE and shear on days with an outbreak of at least ten tornadoes. Here the authors quantify the conditional relationships between precursor SST and SLP variables and localized extremes of CAPE and shear [...]
An autonomous petrological database for geodynamic simulations of magmatic systems
Published: 2021-06-24
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Tectonics and Structure, Volcanology
Self-consistent modelling of magmatic systems is challenging as the melt continuously changes its chemical composition upon crystallization, which may affect the mechanical behaviour of the system. Melt extraction and subsequent crystallization create new rocks while depleting the source region. As the chemistry of the source rocks changes locally due to melt extraction, new calculations of the [...]