Preprints
There are 4720 Preprints listed.
Understanding recent tropospheric ozone trends in the context of large internal variability: A new perspective from chemistry-climate model ensembles
Published: 2022-08-12
Subjects: Physical Sciences and Mathematics
Observational records of meteorological and chemical variables are imprinted by an unknown combination of anthropogenic activity, natural forcings, and internal variability. With a 15-member initial-condition ensemble generated from the CESM2-WACCM6 chemistry-climate model for 1950-2014, we extract signals of anthropogenic (‘forced’) change from the noise of internally arising climate [...]
Validating mechanistic models of fluid displacement during imbibition
Published: 2022-08-11
Subjects: Physical Sciences and Mathematics
Pore-scale modelling is an important tool to improve our understanding of multiphase flow in porous media. Slow fluid invasion is commonly modelled using quasi-static pore network models (PNM). These models simulate the invasion in a network of simplified pores and throats by invading network elements in order of the quasi-static “invasion” capillary pressure needed for the invading fluid to [...]
A note on climate science and climate policy
Published: 2022-08-10
Subjects: Physical Sciences and Mathematics
A short note on climate science and climate policy, discussing planning vs acting, and the differences between decision making and regret under uncertainty and in a deterministic environment.
Geomorphological indicators
Published: 2022-08-09
Subjects: Earth Sciences
Several physical, chemical, and biological processes shape coastal environments close to sea level. Acting through time, these processes create a variety of coastal landforms. When found outside their environment of formation, these landforms can be used by geoscientists as geomorphological indicators of former relative sea levels. In this chapter, we outline the main processes acting on coastal [...]
Majority of 21st century global irrigation expansion has been in water stressed regions
Published: 2022-08-09
Subjects: Agriculture, Spatial Science, Sustainability
The expansion of irrigated agriculture has increased global crop production but resulted in widespread stress to freshwater resources. Ensuring that increases in irrigated production only occur in places where water is relatively abundant is a key objective of sustainable agriculture, and knowledge of how irrigated land has evolved is important for measuring progress towards water sustainability. [...]
Double surface rupture and hydraulic recharge of a three-fault system during the Mw 4.9 earthquake of 11 November 2019 at Le Teil (France)
Published: 2022-08-08
Subjects: Earth Sciences, Geophysics and Seismology, Hydrology, Numerical Analysis and Scientific Computing
The Mw 4.9 earthquake of 11 November 2019 at Le Teil (France) occurred at a very shallow depth (about 1 km) inducing the surface rupture of La Rouvière fault, nearby of a limestone quarry. Thanks to satellite differential interferometry, we detected the existence of the secondary surface rupture of the quasi-parallel Bayne Rocherenard fault. A newly processed seismic cross-section allowed us to [...]
SubZero: A Sea Ice Model with an Explicit Representation of the Floe Life Cycle
Published: 2022-08-08
Subjects: Physical Sciences and Mathematics
Sea ice dynamics exhibit granular behavior as individual floes and fracture networks become particularly evident at length scales O(10--100) km and smaller. However, climate models do not resolve floes and represent sea ice as a continuum, while existing floe-scale sea ice models tend to oversimplify floes using discrete elements of predefined simple shapes. The idealized nature of climate and [...]
Automated stratigraphic correlation and model building using chronostratigraphic principles
Published: 2022-08-07
Subjects: Sedimentology, Software Engineering, Stratigraphy
Stratigraphic correlation of geophysical well logs is one of the most important - and most time-consuming - tasks that applied geoscientists perform on a daily basis. Using the dynamic time warping (DTW) algorithm, automated correlation of two wells is a fairly simple task; DTW can also be used to correlate a large number of wells along a single path. However, errors accumulate along a path and [...]
Estimating the Occurrence of Slow Slip Events and Earthquakes with an Ensemble Kalman Filter
Published: 2022-08-07
Subjects: Applied Mathematics, Earth Sciences, Physical Sciences and Mathematics
Our ability to forecast earthquakes and slow slip events is hampered by limited information on the current state of stress on faults. Ensemble data assimilation methods permit estimating the state by combining physics-based models and observations, while considering their uncertainties. We employ an Ensemble Kalman Filter (EnKF) to estimate shear stresses, slip rates, and the state theta acting [...]
Improved estimation of phytoplankton abundance and fine-scale water quality features via simultaneous discrete and semi-continuous surveys
Published: 2022-08-06
Subjects: Biogeochemistry, Environmental Monitoring, Fresh Water Studies, Oceanography, Water Resource Management
The abundance and distribution of phytoplankton is driven by light and nutrient availability which in turn is controlled by larger-scale regional processes such as climatic variability and global teleconnections. However, such estimates are largely built on evidence gathered from coarse (on the order of kilometers), discrete grab sampling networks where the overall set of measured parameters is [...]
A High-order Accurate Summation-by-Parts Finite Difference Method for Fully-dynamic Earthquake Sequence Simulations within Sedimentary Basins
Published: 2022-08-06
Subjects: Applied Mathematics, Earth Sciences, Physical Sciences and Mathematics
We present a computationally efficient numerical method for earthquake sequences that incorporates wave propagation during rupture. A vertical strike-slip fault governed by rate-and-state friction is embedded in a heterogeneous elastic half-space discretized using a high-order accurate Summation-by-Parts finite difference method. We develop a two solver approach: Adaptive time-stepping is [...]
Within the subducting Nazca Plate: The 2020 Mw 6.8 Calama earthquake and its similarity with the surrounding inslab seismicity
Published: 2022-08-06
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
We study the 2020 MW 6.8 Calama earthquake sequence that occurred within the subducting oceanic Nazca plate. The mainshock is modeled via waveform inversion using a dynamic rupture model, while detection and location techniques are used to better characterize its aftershock sequence. We analyze the local seismotectonic and thermal context of the subducting Nazca plate to understand the trigger [...]
Extensional Deformation of a Shale-dominated Delta: Tarakan Basin, Offshore Indonesia
Published: 2022-08-04
Subjects: Geology, Sedimentology, Tectonics and Structure
Deformation on shale-rich continental margins is commonly associated with thin-skinned extension above mobile shales. Normal faulting and shale mobilization are widespread on such margins, being associated with and controlled by progradation and gravitational failure of deltaic sedimentary wedges. However, due to limitations in our ability to seismically imaging these mobile shales, our [...]
Atlantic Water intrusion triggers rapid retreat and regime change at previously stable Greenland glacier
Published: 2022-08-04
Subjects: Earth Sciences, Glaciology
Ice discharge from Greenland’s marine-terminating glaciers contributes to half of all mass loss from the ice sheet, with numerous mechanisms proposed to explain their retreat. Here, we examine K.I.V Steenstrups Nordre Bræ (‘Steenstrup’) in Southeast Greenland, which, between 2018—2021, retreated ~7 km, thinned ~20%, doubled in discharge, and quadrupled in flow speed. This rate of acceleration is [...]
Field’s Spatial Variation Influenced Outcomes more so than N-fertiliser, FYM, Cover Crops or Their Legacy Effects Following Conversion to a No-till Arable System
Published: 2022-08-04
Subjects: Agricultural Science, Agriculture, Agronomy and Crop Sciences Life Sciences, Environmental Indicators and Impact Assessment, Soil Science, Sustainability
No-till in agricultural arable systems is a practice that offers benefits to soil health. Combined with methods such as the incorporation of crop residues and manures, no-till can influence the dynamics of soil organic carbon (SOC) and organic matter (SOM), crop productivity and nutrient status. These turnovers are shaped by spatial and temporal factors and associated microbial mineralisation [...]