Preprints
Filtering by Subject: Physical Sciences and Mathematics
The Low Permeability of the Earth’s Precambrian Crust
Published: 2022-12-21
Subjects: Physical Sciences and Mathematics
The large volume of deep groundwater in the Precambrian crust has only recently been understood to be relatively hydrogeologically isolated from the rest of the hydrologic cycle. Currently, the paucity of permeability measurements in the Precambrian crust is a barrier to modeling fluid flow and solute transport in these low porosity and permeability deep environments. Estimates of permeability [...]
Acoustic full waveform inversion for 2-D ambient noise source imaging
Published: 2022-12-20
Subjects: Physical Sciences and Mathematics
We present a method for estimating seismic ambient noise sources by acoustic full waveform inversion of interstation cross-correlations. The method is valid at local scales for laterally heterogeneous media, and ambient noise sources confined to the Earth's surface. Synthetic tests performed using an actual field array geometry, are used to illustrate three unique aspects of our work. First: the [...]
Return of the Atacama deep Slow Slip Event : the 5-year recurrence confirmed by continuous GPS
Published: 2022-12-20
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Four years ago, using survey GPS measurements, the first deep slow slip event (SSE) was detected in Chile (near Copiapó, Atacama region), unrelated to any major earthquake. It was located between 40 and 60 km depth on the subduction interface, lasted approximately 18 months (2014-2016.5) and reached an equivalent magnitude of Mw~6.9. The single permanent station operating in the region between [...]
Synthesizing Sea Surface Temperature and Satellite Altimetry Observations Using Deep Learning Improves the Accuracy and Resolution of Gridded Sea Surface Height Anomalies
Published: 2022-12-17
Subjects: Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Gridded sea surface height (SSH) maps estimated from satellite altimetry are widely used for estimating surface ocean geostrophic currents. Satellite altimeters observe SSH along one-dimensional tracks widely spaced in space and time, making accurately reconstructing the two-dimensional (2D) SSH field challenging. Traditionally, SSH is mapped using optimal interpolation (OI). However, OI [...]
Evolution of the seasonal dynamics of the lake-terminating glacier Fjallsjökull, southeast Iceland, inferred using high-resolution repeat UAV imagery
Published: 2022-12-16
Subjects: Earth Sciences, Glaciology, Physical Sciences and Mathematics
Proglacial lakes are becoming ubiquitous at the termini of many glaciers worldwide, leading to increased glacier mass loss and terminus retreat, yet an understanding of the key processes forcing their behaviour is lacking. This study utilised high-resolution repeat uncrewed aerial vehicle (UAV)-Structure from Motion (SfM) imagery to provide insights into the changing dynamics of Fjallsjökull, a [...]
Stinging News: ‘Dickinsonia’ discovered in the Upper Vindhyan of India Not Worth the Buzz
Published: 2022-12-16
Subjects: Earth Sciences, Physical Sciences and Mathematics
A recent report of Dickinsonia tenuis ‘hiding in plain sight’ at the Bhimbetka rock shelters in rocks of the Maihar sandstone (Upper Vindhyan) has important implications for paleogeography and the age of the Upper Vindhyan. We visited the site in December 2022 and found the evidence for Dickisonia lacking. The ‘fossil’ resembles decayed parts of modern Apis dorsata (giant honeybees) hives. In [...]
A treatise on InSAR geometry and 3D displacement estimation
Published: 2022-12-15
Subjects: Engineering, Physical Sciences and Mathematics
The estimation of displacement vectors for (objects on) the Earth’s surface using satellite InSAR requires geometric transformations of the observables based on orbital viewing geometries. Usually, there are insufficient viewing geometries available for full 3D reconstruction, leading to non-unique solutions. Currently, there is no standardized approach to deal with this problem, resulting in [...]
Thermal stratification and meromixis in four dilute temperate zone lakes
Published: 2022-12-14
Subjects: Life Sciences, Physical Sciences and Mathematics
Four adjacent lakes (Arco, Budd, Deming, and Josephine) within Itasca State Park in Minnesota, USA are reported to be meromictic in the scientific literature. However, seasonally persistent chemoclines have never been documented. We collected seasonal profiles of temperature and specific conductance and placed temperature sensor chains in two lakes for ~ 1 year to explore whether these lakes [...]
Citizen and Machine Learning-aided High-resolution mapping of urban heat exposure and stress
Published: 2022-12-13
Subjects: Earth Sciences, Environmental Sciences, Physical Sciences and Mathematics
Through conversion of land cover to more built-up, impervious surfaces, cities are creating hotter environments for urban residents. Existing measurements of heat and heat stress, however, are often insufficient to capture intra-urban variability of exposure. This study provides a replicable method for modeling air temperature, humidity, and heat stress over an urban area, engaging citizens in [...]
Satellite-derived solar radiation for intra-hour and intra-day applications: biases and uncertainties by season and altitude
Published: 2022-12-13
Subjects: Physical Sciences and Mathematics
Accurate estimates of the surface solar radiation (SSR) are a prerequisite for intra-day forecasts of solar resources and photovoltaic power generation. Intra-day SSR forecasts are of interest to power traders and to operators of solar plants and power grids who seek to optimize their revenues and maintain the grid stability by matching power supply and demand. Our study analyzes systematic [...]
Basin-scale hydrodynamics and physical connectivity in a Great Patagonian Lake
Published: 2022-12-07
Subjects: Earth Sciences, Environmental Sciences, Physical Sciences and Mathematics
Patagonian lakes are one of the most unexplored aquatic environments on Earth, and little is known about their thermo-hydrodynamics and current trophic state. Meanwhile, increasing urbanization and industrialization in their catchments compromise their health. Here, we investigate Lake Llanquihue, one of the Earth's great freshwater bodies in Northern Patagonia, Chile. Still considered a pristine [...]
Prescribed burns as a tool to mitigate future wildfire smoke exposure: Lessons for states and rural environmental justice communities
Published: 2022-12-04
Subjects: Physical Sciences and Mathematics
Smoke from wildfires presents one of the greatest threats to air quality, public health, and ecosystems in the United States, especially in the West. Here we quantify the efficacy of prescribed burning as an intervention for mitigating smoke exposure downwind of wildfires across the West during the 2018 and 2020 fire seasons. Using the adjoint of the GEOS-Chem chemical transport model, we [...]
Functional relationships reveal differences in the water cycle representation of global water models
Published: 2022-12-04
Subjects: Physical Sciences and Mathematics
Global water models are increasingly used to understand the past, present, and future water cycle, but disagreements between models make model-based inferences uncertain. While there is empirical evidence of a number of large-scale hydrologic relationships, these relationships are rarely used for model evaluation. Here we evaluate global water models using functional relationships that capture [...]
Estimation and Uncertainty Quantification of Magma Interaction Times using Statistical Emulation
Published: 2022-12-02
Subjects: Applied Statistics, Earth Sciences, Physical Sciences and Mathematics, Volcanology
Evolution of volcanic plumbing systems towards eruptions of different styles and sizes largely depends on processes at crustal depths that are outside our observational capabilities. These processes can be modeled and the outputs of the simulations can be compared with the chemistry of the erupted products, geophysical and geodetic data to retrieve information on the architecture of the plumbing [...]
Persistent effect of El Niño on global economic growth
Published: 2022-12-02
Subjects: Physical Sciences and Mathematics, Social and Behavioral Sciences
El Niño-Southern Oscillation (ENSO) shapes extreme weather globally, causing myriad socioeconomic impacts, but whether economies recover from ENSO events and how anthropogenic changes to ENSO will affect the global economy are unknown. Here we show that El Niño persistently reduces country-level economic growth, attributing $4.1T and $5.7T in global income losses to the 1982-83 and 1997-98 [...]