Preprints
There are 6976 Preprints listed.
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 [...]
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 [...]
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 [...]
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 [...]
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 [...]
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.
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. [...]
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 [...]
Algorithm theoretical basis document for GEDI footprint aboveground biomass density
Published: 2022-08-14
Subjects: Engineering, Physical Sciences and Mathematics
The Global Ecosystem Dynamics Investigation (GEDI) lidar is a multibeam laser altimeter on the International Space Station (ISS). GEDI is the first spaceborne instrument designed to measure vegetation height and to quantify aboveground carbon stocks in temperate and tropical forests and woodlands. This document describes the algorithm theoretical basis underpinning the development of the GEDI [...]
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 [...]
Consumption Ozone-Depleting Substances Impact in Central American GDAP: An Input Oriented Malmquist DEA Index
Published: 2022-08-15
Subjects: Life Sciences, Social and Behavioral Sciences
This study measures the impact of consumption Ozone-Depleting Substances (ODS) on the Gross Domestic Agricultural Product (GDAP) of the Central American Countries. The methodology used is a non-parametric program under Data Envelopment Analyze (DEA) with the Malmquist indices methods. The DEA methodology permits defining the technology bound or performance. It discomposes the total factor [...]
DNA sequencing, microbial sensors, and the discovery of buried mineral resources
Published: 2022-08-14
Subjects: Life Sciences
New mineral resources are critical to both sustaining human population growth and technological improvements that will enable global decarbonization. New and innovative exploration technologies that enable detection of deeply buried mineralization and host rocks are required to meet these demands. Here we show that DNA amplicon sequencing of soil microbial communities resolves anomalies in [...]
Data mining by watching old documentary TV programs to learn about the relationships between people’s lives and the landscape in Sakha in the perestroika era at the end of the 1980s
Published: 2022-08-14
Subjects: Geography
To accurately evaluate the spatiotemporal variability of ecosystem functions and services, as well as biodiversity, under a rapidly changing climate and shifting anthropogenic activities, it is an important but challenging task to retrieve information about past relationships among society, people’s lives, and the landscape. We watched documentary TV programs broadcast by the Japanese public [...]
Distinct roles of cyclones and anticyclones in setting the midwinter minimum of the North Pacific eddy activity. Part II: Eulerian eddy statistics and energetics
Published: 2022-08-14
Subjects: Atmospheric Sciences
The characteristics and dynamics of midlatitude storm-tracks have been long investigated. Nevertheless, our understandings of the storm-tracks, especially the midwinter minimum of the North Pacific storm-track activity, are still limited, partly because Eulerian eddy statistics are incapable of separating cyclonic and anticyclonic contributions. Here we investigate the detailed seasonal evolution [...]
Thermal forcing expected to modulate convection in a mechanically forced stationary wave
Published: 2022-08-16
Subjects: Atmospheric Sciences, Climate, Earth Sciences, Physical Sciences and Mathematics
This is a reply to the comment by Lofverstrom and Thirumalai on our publication in Nature. That comment and this reply underwent peer review at Nature, and Nature declined to publish the exchange