Preprints
Filtering by Subject: Physical Sciences and Mathematics
Globally resolved surface temperatures since the Last Glacial Maximum
Published: 2021-04-01
Subjects: Climate, Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Climate changes across the last 24,000 years provide key insights into Earth system responses to external forcing. Climate model simulations and proxy data have independently allowed for study of this crucial interval; however, they have at times yielded disparate conclusions. Here, we leverage both types of information using paleoclimate data assimilation to produce the first observationally [...]
Crustal-scale listric geometry of the San Andreas Fault driven by lower crustal flow
Published: 2021-03-31
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Physical Sciences and Mathematics
The San Andreas Fault (SAF) is one of the dominant components of the transform boundary between the Pacific and the North American Plate. Although the fault is verti-cal-to sub-vertical at shallow (<10 km) depth, it variably dips at angles of ca. 40-70º to the southwest near the western Transverse Range and to the northeast in its southern seg-ment at depths of ca. 10-20 km, and thus can be [...]
Towards a morphology diagram for terrestrial carbonates: evaluating the impact of carbonate supersaturation and alginic acid in calcite precipitate morphology
Published: 2021-03-30
Subjects: Earth Sciences, Environmental Sciences, Physical Sciences and Mathematics
Ancient and recent terrestrial carbonate-precipitating systems are characterised by a heterogeneous array of deposits volumetrically dominated by calcite. In these environments, calcite precipitates display an extraordinary morphological diversity, from single crystal rhombohedral prisms, to blocky crystalline encrustations, or spherulitic to dendritic aggregates. Despite many decades of thorough [...]
The role of the timing of sudden stratospheric warmings for precipitation and temperature anomalies in Europe
Published: 2021-03-26
Subjects: Physical Sciences and Mathematics
The Northern Hemisphere stratospheric polar vortex (SPV), a band of fast westerly winds over the Pole extending from approximately 10 to 50 km altitude, is a key driver of European winter weather. Extremely weak polar vortex states, so called sudden stratospheric warmings (SSWs), are on average followed by dry and cold weather in Northern Europe, as well as wetter weather in Southern Europe. [...]
Glacier surges controlled by the close interplay between subglacial friction and drainage
Published: 2021-03-26
Subjects: Physical Sciences and Mathematics
The fast flow of glaciers and ice sheets is largely influenced by friction at the ice- bedrock interface, and our imperfect understanding of subglacial friction accounts for one of the largest uncertainties in predictions of future sea-level rise. Glacier motion ranges from slow creep to cyclic surge instabilities and devastating glacier collapse as well as continuously fast-flowing ice-streams. [...]
Titan's prevailing circulation might drive highly intermittent, yet significant sediment transport
Published: 2021-03-26
Subjects: Physical Sciences and Mathematics, Planetary Sciences
Titan, the largest moon of Saturn, is characterized by gigantic linear dunes and an active dust cycle. Much like on Earth, these aeolian processes are caused by the wind-driven saltation of surface grains. It is still unclear, however, how saltation on Titan can occur despite the typically weak surface winds and the potentially cohesive surface grains. Here, we explore the hypothesis that [...]
Spatial spectrum of temperature fluctuations in buoyancy driven chaotic and turbulent atmosphere
Published: 2021-03-26
Subjects: Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Planetary Sciences
It is shown, using results of direct numerical simulations, laboratory experiments, measurements in the atmospheric boundary layer, in troposphere, in stratosphere, and the satellite infrared radiances data that in many cases the temperature fluctuations in buoyancy driven chaotic and turbulent atmosphere can be well described by the distributed chaos approach based on the Bolgiano-Obukhov [...]
Resolving Northern Alaska Earthquake Sequences Using the Transportable Array and Probabilistic Location Methods
Published: 2021-03-25
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Tectonics and Structure
Between 2014 and 2017, almost 200 new seismic stations were installed in Alaska and northwestern Canada as part of the EarthScope USArray Transportable Array. These stations currently provide an unprecedented capability for the detection and location of seismic events in regions with otherwise relatively sparse station coverage. Two interesting earthquake sequences in 2018 and 2019 in the [...]
Shape of plutons in crustal shear zones: A tectono-magmatic guide based on analogue models
Published: 2021-03-24
Subjects: Physical Sciences and Mathematics
Plutons in crustal shear zones may exploit inherited structures, interfere with strain localizing or be deformed passively. To constrain the relative timing of such tectono-magmatic constellations in natural settings is not always straight-forward. We here present sandbox-type analogue model experiments simulating magma emplacement into simple and transtensional crustal shear zones to test the [...]
Prediction of rapid intensification of tropical cyclones with deep learning
Published: 2021-03-24
Subjects: Physical Sciences and Mathematics
Tropical cyclones (TC) are one of the most destructive natural events claiming a lot of human lives and devastating coastal areas. Despite the advanced understanding of the formation of TC, prediction capabilities on the rapid intensification (RI) of TCs remain unsatisfactory. In this study, a deep learning framework using satellite images is used for the first time to identify RI events. We [...]
The role of random vorticity stretching in tropical depression genesis
Published: 2021-03-23
Subjects: Physical Sciences and Mathematics
Tropical deep convection plays a key role at the tropical depression stage of tropical cyclogenesis by aggregating vorticity, but no existing theory can depict such a stochastic vorticity aggregation process. Vorticity probability distribution function (PDF) is proposed as a tool to predict the horizontal structure and wind speed of the tropical depression, a tropical cyclone in its early stage. [...]
Complex Network Theoretic Assessment of Precipitation Driven Meteorological Drought in India: Past and Future
Published: 2021-03-22
Subjects: Physical Sciences and Mathematics
Spatio-temporal analysis of droughts is of paramount importance especially for future climate scenarios. We use complex network theoretic measures to understand spatio-temporal properties of precipitation driven meteorological drought across India in past and future climate scenarios. We construct drought networks using Event synchronization (ES) for moderate and extreme drought conditions [...]
Carbon dioxide fluxes increase from day to night across European streams
Published: 2021-03-22
Subjects: Physical Sciences and Mathematics
Globally, inland waters emit over 2 Pg of carbon (C) per year as carbon dioxide (CO2), of which the majority originates from streams and rivers. Despite the global significance of fluvial CO2 emissions, little is known about their diel dynamics. We present the first large-scale assessment of day- and night-time CO2 fluxes at the water-air interface across European streams. Fluxes were directly [...]
Western Gondwana imaged by S receiver-functions (SRF): new results on Moho, MLD (mid-lithospheric discontinuity) and LAB (lithosphere-asthenosphere boundary)
Published: 2021-03-21
Subjects: Earth Sciences, Physical Sciences and Mathematics
We study the Moho, the mid-lithospheric discontinuity (MLD), and the lithosphere-asthenosphere boundary (LAB) from southern Africa to northern Arabia, from Archean cratons to active rifts, at 1° resolution using our comprehensive new database of shear-wave receiver functions (SRFs). The good agreement between the Moho depth obtained from our SRFs and published P-wave receiver function (PRF) [...]
Mechanical Stratigraphy Controls Normal Fault Growth and Dimensions, Outer Kwanza Basin, Offshore Angola
Published: 2021-03-20
Subjects: Earth Sciences, Geology, Physical Sciences and Mathematics, Tectonics and Structure
Mechanical stratigraphy controls the growth patterns and dimensions of relatively small normal faults, yet how its influences the development of much larger structures remains unclear. Here we use 3D seismic reflection data from the Outer Kwanza Basin, offshore Angola to constrain the geometry and kinematics of several normal faults formed in a deep-water clastic succession. The faults are up to [...]