Preprints
There are 5932 Preprints listed.
Global air quality change during COVID-19: a synthetic result of human activities and meteorology
Published: 2020-12-19
Subjects: Atmospheric Sciences
In recent months, coronavirus disease 2019 (COVID-19) has been spreading around the globe, and this has led to a rare reduction in human activities. In such a background, data from ground-based environmental stations, satellites, and reanalysis materials are utilized to conduct a comprehensive analysis of the air quality changes during the COVID-19 outbreak at the global scale. The results showed [...]
Idealized forecast-assimilation experiments for convective-scale Numerical Weather Prediction
Published: 2020-12-18
Subjects: Meteorology, Oceanography and Atmospheric Sciences and Meteorology
To aid understanding of and facilitate research into forecast-assimilation systems of Numerical Weather Prediction (NWP), idealized models that embody essential characteristics of these systems can be used. This article concerns the use of such an idealized fluid model of convective-scale NWP in inexpensive data assimilation (DA) experiments. The forecast model, introduced in Kent et al (2017), [...]
Small-scale lithospheric heterogeneity characterization using Bayesian inference
Published: 2020-12-18
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Observations from different disciplines have shown that our planet is highly heterogeneous at multiple scale lengths. Still, many seismological Earth models tend not to include any small-scale heterogeneity or lateral velocity variations, which can affect measurements and predictions based on these homogeneous models. In this study, we describe the lithospheric small-scale heterogeneity structure [...]
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 [...]
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 [...]
Constraining the 410-km Discontinuity and Slab Structure in the Kuril Subduction Zone with Triplication Waveforms
Published: 2020-12-18
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 [...]
The UK needs an open data portal dedicated to coastal flood and erosion hazard risk and resilience
Published: 2020-12-18
Subjects: Geographic Information Sciences, Geomorphology, Natural Resources Management and Policy, Nature and Society Relations, Sustainability
In the UK, coastal flooding and erosion are two of the primary climate-related hazards to communities, businesses, and infrastructure. To better address the ramifications of those hazards, now and into the future, the UK needs to transform its scattered, fragmented coastal data resources into a systematic, integrated, quality-controlled, openly accessible data portal. Such a portal would support [...]
Multi-decadal improvement in U.S. lake water clarity
Published: 2020-12-18
Subjects: Biogeochemistry, Hydrology, Water Resource Management
Across the globe, recent work examining the state of freshwater resources paints an increasingly dire picture of degraded water quality. However, much of this work either focuses on a small subset of large waterbodies or uses in situ water quality datasets that contain biases in when and where sampling occurred. Using these unrepresentative samples limits our understanding of landscape level [...]
Uncertainty Estimation with Deep Learning for Rainfall-Runoff Modelling
Published: 2020-12-18
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 [...]
Future changes in Northern Hemisphere summer weather persistence linked to projected Arctic warming.
Published: 2020-12-18
Subjects: Physical Sciences and Mathematics
Understanding the response of the large-scale atmospheric circulation to climatic change remains a key challenge. Specifically, changes in the equator-to-pole temperature difference have been suggested to affect the mid-latitudes, potentially leading to more persistent extreme weather, but a scientific consensus has not been established so far. Here we quantify summer weather persistence by [...]
Assessing geomorphic change in restored coastal dune ecosystems using a multi-platform aerial approach
Published: 2020-12-18
Subjects: Physical Sciences and Mathematics
Uncrewed aerial systems (UAS) provide an effective method to examine geomorphic and vegetation change in restored coastal dune ecosystems. Coupling structure-from-motion (SfM) photogrammetry with RGB orthomosaic imagery allows researchers to characterize spatial-temporal geomorphic responses associated with differences in vegetation cover. Such approaches provide quantitative data on landscape [...]
Mechanisms for avulsion on alluvial fans: insights from high-frequency topographic data
Published: 2020-12-18
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 [...]
Quantitative uncertainty analysis of gravity disturbance. The case of the Geneva Basin (Switzerland)
Published: 2020-12-18
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Gravity data from the International Gravimetric Bureau and the Gravimetric Atlas of Switzerland have been used to evaluate their application and limitations as a subsurface investigation tool to constrain key geological structures in support of the georesources exploration in the Geneva Basin (GB). In this context, the application of an effective processing workflow able to produce a [...]
Bookshelf Kinematics and the Effect of Dilatation on Fault Zone Inelastic Deformation: Examples from Optical Image Correlation Measurements of the 2019 Ridgecrest Earthquake Sequence
Published: 2020-12-18
Subjects: Physical Sciences and Mathematics
The 2019 Ridgecrest earthquake sequence initiated on July 4th with a series of foreshocks, including a Mw 6.4 event, that culminated a day later with the Mw 7.1 mainshock and resulted in rupture of a set of cross-faults. Here we use sub-pixel correlation of optical satellite imagery to measure the displacement, finite strain and rotation of the near-field coseismic deformation to understand 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 [...]