A5017266588- earthquake and tectonic studies
- Geological and Geochemical Analysis
- Cryospheric studies and observations
- Color Science and Applications
- Synthetic Aperture Radar (SAR) Applications and Techniques
- Luminescence Properties of Advanced Materials
- Landslides and related hazards
- Geological and Geophysical Studies
- Radiation Detection and Scintillator Technologies
- Geological and Tectonic Studies in Latin America
- Earthquake Detection and Analysis
- Color perception and design
- Seismology and Earthquake Studies
- Seismic Waves and Analysis
- Scientific Computing and Data Management
- Climate change and permafrost
- Arctic and Antarctic ice dynamics
- Impact of Light on Environment and Health
- Atmospheric and Environmental Gas Dynamics
- Advanced Chemical Sensor Technologies
- Distributed and Parallel Computing Systems
- Inorganic Fluorides and Related Compounds
- Building Energy and Comfort Optimization
- Computational Physics and Python Applications
- Geochemistry and Geologic Mapping
Earth and Space Research
2018-2025
University of Washington
2018-2025
Washington College
2023
Seattle University
2018-2022
Cornell University
2013-2020
Universidad de Los Andes
2016-2017
United States Geological Survey
2015
Menlo School
2015
Computer Technology Associates (United States)
1993-2002
EMI (United Kingdom)
1946
Spectral distributions of 622 samples daylight (skylight, and sunlight plus skylight) have been subjected to characteristic vector analysis, as composite data in three subgroups (99 measured by Budde; 249, Condit; 274, Henderson Hodgkiss). The chromaticity coordinates (x,y) computed from these compared with direct visual determinations Nayatani Wyszecki, Chamberlin, Lawrence, Belbin. It was found that the chromaticities indicated spectral colorimetry cluster about curve: y =...
The computer program, Scoops3D, evaluates slope stability throughout a digital landscape represented by elevation model (DEM). program uses three-dimensional (3D) method of columns approach to assess the many (typically millions) potential landslides within user-defined size range. For each landslide (or failure), Scoops3D assesses rotational, spherical slip surface encompassing DEM cells using 3D version either Bishop’s simplified or Ordinary (Fellenius) limit-equilibrium analysis. has...
Abstract Volcanoes are hazardous to local and global populations, but only a fraction continuously monitored by ground‐based sensors. For example, in Latin America, more than 60% of Holocene volcanoes unmonitored, meaning long‐term multiparameter data sets volcanic activity rare sparse. We use satellite observations degassing, thermal anomalies, surface deformation spanning 17 years at 47 the most active America compare these archived Global Volcanism Program. This first comparison...
The Planet SkySat-C SmallSat constellation can acquire very high resolution (0.7 m to 0.9 m) triplet stereo and video imagery with short revisit times, providing an exciting opportunity for global, on-demand 3D mapping of dynamic surface features. However, a lack suitable processing software, limited geolocation accuracy, scene-to-scene offsets currently limit the potential accurate SkySat digital elevation model (DEM) production. We developed open-source workflow refine camera models...
Decadal trends of volcanic deformation in the Central Andes Volcanic Zone (CVZ) are identified with Interferometric Synthetic Aperture Radar (InSAR) stacks and time series velocity maps covering an area 19°S–27°S 66°W–69°W. We combine over 750 ERS Envisat interferograms from two descending three ascending tracks. These tracks cover 100,000 km 2 span 1992–2011. Our analysis extends observations at Cerro Blanco, Uturuncu, Lazufre centers uncovers previously undocumented centers: Overo Northern...
A series of measurements, extending over a year, was made at Enfield, Middlesex, using grating monochromator to determine the spectral energy distribution daylight between 3000 and 8000 Å, particularly total sky radiation without direct sunlight. The results are considered with respect structure curves, their equivalent chromaticities related full radiator distributions. Average distributions given for several sources including those limits usual range used in colour matching. From these,...
Within Latin America, about 319 volcanoes have been active in the Holocene, but 202 of these no seismic, deformation or gas monitoring. Following 2012 Santorini Report on satellite Earth Observation and Geohazards, Committee Satellites (CEOS) developed a 4-year pilot project (2013-2017) to demonstrate how observations can be used monitor large numbers cost-effectively, particularly areas with scarce instrumentation and/or difficult access. The aims improve disaster risk management (DRM) by...
The Central Andes is a key global location to study the enigmatic relation between volcanism and plutonism because it has been site of large ignimbrite-forming eruptions during past several million years currently hosts world’s largest zone silicic partial melt in form Altiplano-Puna Magma (or Mush) Body (APMB) Southern Puna (SPMB). In this themed issue, results from recently completed PLUTONS project are synthesized. This focused an interdisciplinary on two regions large-scale surface...
Abstract The timing of snowmelt runoff is critical for water resource applications, but its spatiotemporal evolution remains poorly understood. We present a scalable approach to map onset using Sentinel‐1 synthetic aperture radar data the past 8 years with 10 m spatial resolution and median temporal 3.9 days. A systematic analysis stratovolcanoes in Western United States showed that strongly dependent on elevation ( r = 0.81), lapse rate 4.9 days per 100 gain. During 2015 snow drought, we...
SUMMARY In December, 2009, a rare sequence of earthquakes initiated within the weakly extended Western Rift East African system in Karonga province northern Malawi, providing unique opportunity to characterize active deformation associated with intrabasinal faults an early-stage rift. We combine teleseismic and regional seismic recordings largest events, InSAR imagery primary sequence, aftershocks from temporary (4-month) local network six seismometers delineate extent geometry faulting. The...
There is a continuing demand for new phosphors in the fluorescent lamp industry and initial stages of search suitable materials are essentially chemical nature. Some techniques used this work illustrated by reference to large group alkaline earth pyrophosphate recently developed. These utilize Sn2+ or Ce4+ as primary activator manganese secondary activator, considerable potential application.
SlideRule is an open source server-side framework for on-demand processing of science data in the cloud.The project offers a new paradigm NASA archival management -rapid delivery customizable products, rather than hosting large volumes standard derivative which will inevitably be insufficient some applications.
icepyx is both a software library and community composed of ICESat-2 (NASA satellite) data users, developers, maintainers, the scientific community.We are working together to develop shared resources -including existing resources, new code, tutorials, use-cases/examples -that simplify process querying, obtaining, analyzing, manipulating datasets enable discovery.
A 150-km-wide ground deformation anomaly in the Altiplano-Puna volcanic complex (APVC) of Central Andes, with uplift centered on Uturuncu volcano and peripheral subsidence, alludes to subsurface stress changes. In particular, role a large, geophysically anomalous partially molten reservoir (the magma body, APMB), located ∼20 km beneath deforming surface, is still poorly understood. To explain observed spatiotemporal pattern, we integrate geophysical petrological data develop numerical model...
The active centre theory of luminescence, with certain assumptions, leads to the expectation exponential growth and decay processes in light emission. Measurement has shown widespread occurrence processes, though details are much more complex than simple would suggest. effects changing current density temperature were examined. phosphors studied fell into two classes, distinguished mainly by rates measured. Some non-exponential found, especially long time decay, but none definitely bimolecular.
The structure of prussic acid has been a subject constant interest ever since Gautier, by his discovery the isocyanides provided an alternative formula for acid. In general, opinion leaned towards view that free is cyanide rather than isocyanide. particular, Wade regarded its relatively unobjectionable physiological properties as evidence structure; but isocyanide found Peratoner and Palazzo in conversion into methyl action diazomethane. A possible compromise may be suggestion, already made...
Abstract Geomorphic features near strike‐slip faults, including offset channels, have long been used in paleoseismology. Recent numerical models suggest that slip rate information can also be expressed far upstream of faults as catchments respond to stream lengthening and shortening due captures along the fault. Slow‐moving show dynamic catchment‐wide responses with migrating ridges changing basins, whereas fast more stable basins distinct topography from faults. Such patterns hold promise...
New continuous GPS observations near the summit of Uturuncu volcano, Bolivia, indicate an average uplift rate 2.4 ± 1.9 mm/yr between April 2010 and November 2015, while previous interferometric synthetic aperture radar (InSAR) May 1992 January 2011 predict vertical 7 2 mm/yr. However, time series is better fit with a time-dependent function, such that in less than 2015 may be as high 9 Motivated by indications non-constant series, we examine to what extent past InSAR measurements have been...
The preparation of a new phosphor is described : barium pyrophosphate containing about 30 molar per cent titanium dioxide but no other addition. mechanism its formation has been examined by differential thermal analysis and x‐ray diffraction, the structure not yet fully elucidated. Its luminescent properties are similar in many respects to those magnesium tungstate, for which it useful substitute fluorescent lamps. It short afterglow, high efficiency, good maintenance mercury discharge, an...
Much has been published on the emission spectra of solid fluorescent materials when excited by various kinds radiation, especially ultraviolet light. The study comparatively few cases line emission, for example, Tomaschek and Deutschbein, given precise results in contrast to very variable data available band spectra. methods adopted earlier work determining position bands have frequently inexact or liable subjective errors. Lenard his school (1928) used spectrophotometer even a direct vision...
Abstract The diversity in the lightning parameterizations for numerical weather and climate models causes considerable uncertainty prediction. In this study, we take a data-driven approach to address parameterization problem, by combining machine learning (ML) techniques with rich observations from World Wide Lightning Location Network. Three ML algorithms are trained over contiguous United States (CONUS) predict stroke density 1° box based on information about atmospheric variables same...
Abstract We developed an open source, extensible Python‐based framework, that we call the Versatile Modeling Of Deformation (VMOD), for forward and inverse modeling of crustal deformation sources. VMOD abstracts from specific source model implementations, data types inversion methods. implement most common geodetic models which can be combined to analyze multi‐source deformation. supports Global Navigation Satellite System (GNSS), InSAR, electronic distance measurement, Leveling tilt data....
NASA established the Surface Topography and Vegetation (STV) Incubation program to develop mature next-generation measurement approaches precisely map Earth’s changing surface overlying vegetation structure, prepare for a dedicated satellite mission within next decade. Over past two decades, large archives of 3D elevation measurements by airborne instruments including LiDAR, altimeters, Synthetic Aperture Radar, stereo optical imagery have been systematically collected, though not...
Geodetic surveys of Volcan Uturuncu and the Lazufre volcanic complex in Central Andes South America reveal sustained surface uplift from magmatic intrusion at depth. However, decadal timescales geodetic are short relative to magma chamber growth. Thus, geodesy alone, it is difficult infer deformation hence accumulation history these volcanoes. Here we combine data InSAR, long-wavelength topography, GPS high-resolution topographic lake shorelines rivers, lava flow morphology constrain...