Preprints
There are 6976 Preprints listed.
Saving the world from your couch: The heterogeneous medium-run benefits of COVID-19 lockdowns on air pollution
Published: 2020-12-12
Subjects: Physical Sciences and Mathematics, Social and Behavioral Sciences
In Spring 2020, COVID-19 led to an unprecedented halt in public and economic life across the globe. In an otherwise tragic time, this provides a unique natural experiment to investigate the environmental impact of such a (temporary) ``de-globalization". Here, we estimate the medium-run impact of a battery of COVID-19 related lockdown measures on air quality across 162 countries, going beyond the [...]
Chevrons: origin and relevance for the reconstruction of past wind regimes
Published: 2020-12-15
Subjects: Climate, Earth Sciences, Geology, Geomorphology, Meteorology, Other Life Sciences, Sedimentology, Stratigraphy
Since its first use in the late 80’s, the term chevron has been employed in numerous studies to describe large U- and V-shaped ridges found in or near shorelines worldwide. Most studies have so far focused on Bahamian chevrons that are exclusively of Late Pleistocene age, and on the supposed Holocene chevrons found in S-Madagascar and Australia. In the Bahamas, these deposits have been [...]
Evaluation of the Grillo sensor, a low-cost accelerometer for IoT-based Real-time seismology
Published: 2021-01-02
Subjects: Geophysics and Seismology
Micro-Electro-Mechanical (MEMS) accelerometers are useful for real-time seismology due to their ability to record strong, unsaturated seismic signals. Recent advances in MEMS technologies enable design of instruments with improved capabilities that also allow recording of small signals. As a result, MEMS can be useful across a broad dynamic range and for both major earthquakes and smaller [...]
Differences in carbon isotope discrimination between angiosperm and gymnosperm woody plants, and their geological significance
Published: 2020-12-13
Subjects: Biogeochemistry, Climate, Geochemistry, Oceanography and Atmospheric Sciences and Meteorology, Paleobiology
For most of the Phanerozoic Eon, Earth’s woody vegetation has been dominated by C3 plants – predominantly gymnosperms - with angiosperms only emerging as the dominant plant group as CO2 declined during the Cenozoic (66 Ma onward). At present, differences in carbon isotope discrimination (Δ13C) between angiosperm and gymnosperm plants are relatively small (2–3 ‰), but an increasing body of [...]
Anatomy of Strike Slip Fault Tsunami-genesis
Published: 2020-12-13
Subjects: Earth Sciences, Engineering, Fluid Dynamics, Geophysics and Seismology, Physical Sciences and Mathematics, Physics
Tsunami generation from earthquake induced seafloor deformations has long been recognized as a major hazard to coastal areas. Strike-slip faulting has generally been believed as insufficient for triggering large tsunamis, except through the generation of submarine landslides. Herein, we demonstrate that ground motions due to strike-slip earthquakes can contribute to the emergence of large [...]
Initial model construction for intermediate-period full-waveform inversion of the contiguous US and surrounding regions
Published: 2020-12-15
Subjects: Geophysics and Seismology
Contiguous US is one of regions well instrumented with broadband seismic stations due to the deployment of the EarthScope Transportable Array. Previous studies have provided various 3D seismic wave speed models for the crust and upper mantle with improving resolution. However, discrepancies exist between these models due to the differences in both data sets and tomographic methods, which [...]
Global models for short-term earthquake forecasting and predictive skill assessment
Published: 2020-12-16
Subjects: Physical Sciences and Mathematics
We present rigorous tests of global short-term earthquake forecasts using Epidemic Type Aftershock Sequence models with two different time kernels (one with exponentially tapered Omori kernel (ETOK) and another with linear magnitude dependent Omori kernel (MDOK)). The tests are conducted with three different magnitude cutoffs for the auxiliary catalog (M3, M4 or M5) and two different magnitude [...]
Climate change research and action must look beyond 2100
Published: 2020-12-16
Subjects: Environmental Sciences, Environmental Studies, Geography, Human Geography, Nature and Society Relations, Oceanography and Atmospheric Sciences and Meteorology, Physical and Environmental Geography, Physical Sciences and Mathematics, Social and Behavioral Sciences
Anthropogenic activity is changing Earth’s climate and ecosystems in ways that are potentially dangerous and disruptive to humans. Greenhouse gas concentrations in the atmosphere continue to rise, ensuring these changes will be felt for centuries beyond 2100, the current benchmark for prediction. Estimating the effects of past, current, and potential future emissions to only 2100 is therefore [...]
Uncertainty Estimation with Deep Learning for Rainfall-Runoff Modelling
Published: 2020-12-17
Subjects: Earth Sciences, Hydrology
Deep Learning is becoming an increasingly important way to produce accurate hydrological predictions across a wide range of spatial and temporal scales. Uncertainty estimations are critical for actionable hydrological forecasting, and while standardized community benchmarks are becoming an increasingly important part of hydrological model development and research, similar tools for benchmarking [...]
Mechanisms for avulsion on alluvial fans: insights from high-frequency topographic data
Published: 2020-12-17
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
Avulsion is a key process in building alluvial fans, but it is also a formidable natural hazard. Based on laboratory experiments monitored with novel high-frequency photogrammetry, we present a new model for avulsion on widely graded gravel fans. Previous experimental studies of alluvial fans have suggested that avulsion occurs in a periodic autogenic cycle, that is thought to be mediated by the [...]
The influence of orbital parameters on the North American Monsoon system during the Last Interglacial Period
Published: 2020-12-17
Subjects: Atmospheric Sciences, Climate, Earth Sciences, Environmental Sciences, Hydrology, Oceanography and Atmospheric Sciences and Meteorology
The response of summer precipitation in the western U.S. to climate variability remains a subject of uncertainty. For example, paleoclimate records indicate the North American monsoon (NAM) was stronger and spatially more extensive during the Holocene, whereas recent modeling suggests a weakened NAM response to increasing temperatures. These illustrate diverging pictures of the NAM response to [...]
The 2020 Mw 6.5 Monte Cristo Range, Nevada earthquake: relocated seismicity shows rupture of a complete shear-crack system
Published: 2020-12-18
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Tectonics and Structure
The predominant model for earthquake faulting is a shear crack, including surrounding damage zones. Observation of this complete shear crack system at seismogenic depth, however, has been elusive. Shear cracks with damage zones are related to fault formation and growth, and earthquake rupture physics and size, but observational and analytical limitations impede use of the shear crack paradigm in [...]
Evidence-based conservation in a changing world: lessons from waterbird individual-based models
Published: 2020-12-16
Subjects: Engineering, Physical Sciences and Mathematics, Social and Behavioral Sciences
Drivers of environmental change are causing novel combinations of pressures on ecological systems. Prediction in ecology often uses understanding of past conditions to make predictions to the future, but such an approach can breakdown when future conditions have not previously been encountered. Individual-based models (IBMs) consider ecological systems as arising from the adaptive behaviour and [...]
Constraining the 410-km Discontinuity and Slab Structure in the Kuril Subduction Zone with Triplication Waveforms
Published: 2020-12-17
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
The detailed structure near the 410-km discontinuity provides key constraints of the dynamic interactions between the upper mantle and the lower mantle through the mantle transition zone (MTZ) via mass and heat exchange. Meanwhile, the temperature of the subducting slab, which can be derived from its fast wave speed perturbation, is critical for understanding the mantle dynamics in subduction [...]
Given that the Paris Agreement is unlikely to prevent dangerous climate overshoot, an alternative risk management strategy is urgently needed
Published: 2020-12-18
Subjects: Life Sciences, Physical Sciences and Mathematics, Social and Behavioral Sciences
Because the 2015 Paris Agreement will not prevent dangerous climate change, there is an urgent need to develop an alternative mitigation strategy. Even if most countries greatly increase their commitments and technological breakthroughs accelerate the transition to emission-free technologies, the 2°C target will still be overshot due to systemic inertia from existing greenhouse gases, warming [...]