A5082477971- Atmospheric and Environmental Gas Dynamics
- Atmospheric Ozone and Climate
- Planetary Science and Exploration
- Geochemistry and Geologic Mapping
- Geophysics and Gravity Measurements
- Ionosphere and magnetosphere dynamics
- Isotope Analysis in Ecology
- Atmospheric chemistry and aerosols
- High-Velocity Impact and Material Behavior
- Spectroscopy and Laser Applications
- Space Exploration and Technology
- Astro and Planetary Science
- Earthquake Detection and Analysis
- Image Processing and 3D Reconstruction
- Air Quality Monitoring and Forecasting
- Additive Manufacturing and 3D Printing Technologies
- GNSS positioning and interference
- Remote-Sensing Image Classification
- Geomagnetism and Paleomagnetism Studies
- Methane Hydrates and Related Phenomena
- Solar and Space Plasma Dynamics
- Mechanical Engineering and Vibrations Research
- Spacecraft Design and Technology
- Scientific Computing and Data Management
- Hydrocarbon exploration and reservoir analysis
Jet Propulsion Laboratory
2014-2025
California Institute of Technology
2005-2021
University of California, Los Angeles
2000
Abstract. NASA's Orbiting Carbon Observatory-2 (OCO-2) has been measuring carbon dioxide column-averaged dry-air mole fraction, XCO2, in the Earth's atmosphere for over 2 years. In this paper, we describe comparisons between first major release of OCO-2 retrieval algorithm (B7r) and XCO2 from OCO-2's primary ground-based validation network: Total Column Observing Network (TCCON). The retrievals, after filtering bias correction, agree well when aggregated around coincident with TCCON data...
Abstract. The Orbiting Carbon Observatory-2 (OCO-2) carries and points a three-channel imaging grating spectrometer designed to collect high-resolution, co-boresighted spectra of reflected sunlight within the molecular oxygen (O2) A-band at 0.765 microns carbon dioxide (CO2) bands 1.61 2.06 microns. These measurements are calibrated then combined into soundings that analyzed retrieve spatially resolved estimates column-averaged CO2 dry-air mole fraction, XCO2. Variations XCO2 in space time...
Abstract. Since September 2014, NASA's Orbiting Carbon Observatory-2 (OCO-2) satellite has been taking measurements of reflected solar spectra and using them to infer atmospheric carbon dioxide levels. This work provides details the OCO-2 retrieval algorithm, versions 7 8, used derive column-averaged dry air mole fraction CO2 (XCO2) for roughly 100 000 cloud-free recorded by each day. The algorithm is based on Atmospheric Observations from Space (ACOS) which applied observations Greenhouse...
Abstract. Here, we report preliminary estimates of the column averaged carbon dioxide (CO2) dry air mole fraction, XCO2, retrieved from spectra recorded over land by Greenhouse gases Observing Satellite, GOSAT (nicknamed "Ibuki"), using retrieval methods originally developed for NASA Orbiting Carbon Observatory (OCO) mission. After screening clouds and other known error sources, these retrievals reproduce much expected structure in global XCO2 field, including its variation with latitude...
Abstract. We describe a method of evaluating systematic errors in measurements total column dry-air mole fractions CO2 (XCO2) from space, and we illustrate the by applying it to v2.8 Atmospheric Observations Space retrievals Greenhouse Gases Observing Satellite (ACOS-GOSAT) over land. The approach exploits lack large gradients XCO2 south 25° S identify large-scale offsets other biases ACOS-GOSAT data with several retrieval parameters instrument calibration. demonstrate effectiveness...
Abstract. The Orbiting Carbon Observatory-2 (OCO-2) is the first National Aeronautics and Space Administration (NASA) satellite designed to measure atmospheric carbon dioxide (CO2) with accuracy, resolution, coverage needed quantify CO2 fluxes (sources sinks) on regional scales. OCO-2 was successfully launched 2 July 2014 has gathered more than years of observations. v7/v7r operational data products from September January 2016 are discussed here. On monthly timescales, 7 12 % these...
Abstract The quest to find extraterrestrial life is a critical scientific endeavor with civilization-level implications. Icy moons in our solar system are promising targets for exploration because their liquid oceans make them potential habitats microscopic life. However, the lack of precise definition poses fundamental challenge formulating detection strategies. To increase chances unambiguous detection, suite complementary instruments must sample multiple independent biosignatures (e.g.,...
Superpixels are homogeneous image regions comprised of multiple contiguous pixels. Superpixel representations can reduce noise in hyperspectral images by exploiting the spatial contiguity scene features. This paper combines superpixels with endmember extraction to produce concise mineralogical summaries that assist browsing large catalogs. First, a graph-based agglomerative algorithm oversegments image. We then use segments' mean spectra as input existing statistical detection algorithms...
Abstract. The Orbiting Carbon Observatory-2 (OCO-2) carries and points a three-channel imaging grating spectrometer designed to collect high-resolution, co-boresighted spectra of reflected sunlight within the molecular oxygen (O2) A-band at 0.765 microns carbon dioxide (CO2) bands 1.61 2.06 microns. These measurements are calibrated then combined into soundings that analyzed retrieve spatially resolved estimates column-averaged CO2 dry air mole fraction, XCO2. Variations XCO2 in space time...
Abstract. Satellite measurements are often compared with higher-precision ground-based as part of validation efforts. The satellite soundings rarely perfectly coincident in space and time the measurements, so a colocation methodology is needed to aggregate "nearby" into what instrument would have seen at location interest. We particularly interested efforts for satellite-retrieved total column carbon dioxide (XCO2), where XCO2 data from Greenhouse Gas Observing (GOSAT) retrievals (ACOS,...
Given a world increasingly dominated by climate extremes, modifying the Earth's with large-scale geoengineering intervention is inevitable. However, faces conundrum: forecasting consequences of accurately in system for which we have incomplete observations and an imperfect understanding. We evaluate global response potential implications mitigation deployment utilizing CRU TS4.08 observations, ERA5 reanalysis data, CMIP6 scenario-based UKESM0-1-LL simulations. From 1950 to 2022, weighted...
We use simultaneous global observations of the mid‐latitude trough and plasmapause to experimentally prove a long‐standing conjecture magnetosphere‐ionosphere coupling‐ namely are on same field line. Global Ionospheric Maps (GIM), generated using ground based GPS receivers, used detect globally extended trough; while IMAGE EUV pictures estimate position. Observations during equinox solstices quiet disturbed periods analyzed. In addition, positions calculated simple empirical model. The two...
The Jet Propulsion Laboratory/University of Southern California Global Assimilation Ionospheric Model (JPL/USC GAIM) uses two data assimilation techniques to optimally combine ionospheric measurements with the physics model: a sparse, traditional Kalman filter estimate three‐dimensional density state, and four‐dimensional variational approach (4DVAR) drivers such as equatorial E × B drift or neutral winds. In this paper we study specific implementation JPL/USC GAIM (single ion,...
Abstract. Many modern instruments generate more data than may be fully processed in a timely manner. For some atmospheric sounders, much of the raw cannot into meaningful observations due to suboptimal viewing conditions, such as presence clouds. Conventional solutions are quick, empirical-threshold filters hand-created by domain experts weed out unlikely or unreasonable observations, coupled with randomized down sampling when volume is still too high. In this paper, we describe method for...
Abstract. Since September 2014, NASA's Orbiting Carbon Observatory-2 (OCO-2) satellite has been taking measurements of reflected solar spectra and using them to infer atmospheric carbon dioxide levels. This work provides details the OCO-2 retrieval algorithm, versions 7 8, used derive column-averaged dry air mole fraction CO2,/sub> (XCO2) for roughly 100,000 cloud-free recorded by each day. The algorithm is based on Atmospheric Observations from Space (ACOS) which applied observations...
Artificial intelligence (AI), which encompasses machine learning (ML), has become a critical technology due to its well-established success in wide array of applications. However, the proper application AI remains central topic discussion many safety-critical fields. This limited autonomous systems difficulty ensuring algorithms will perform as desired and that users understand trust how they operate. In response, there is growing demand for trustability address both expectations concerns...
As artificial intelligence (AI) is increasingly proposed for new and future capabilities in space missions, the question of how to trust AI-enabled autonomy has been explored. Recently, a collaboration between The Aerospace Corporation (Aerospace) NASA's Jet Propulsion Laboratory (JPL) investigated Aerospace's Trusted AI Framework could be applied two JPL projects that planned on leveraging critical autonomous tasks. This combined effort led many insights into practical implementation...
The NASA Planetary Data System hosts millions of images acquired from the planet Mars. To help users quickly find interest, we have developed and deployed content-based classification search capabilities for Mars orbital surface images. systems are publicly accessible using PDS Image Atlas. We describe process training, evaluating, calibrating, deploying updates to two CNN classifiers collected by missions. also report on three years deployment including usage statistics, lessons learned,...
[1] We present a semiautomated method to extract spectral end-members from hyperspectral images. This employs superpixels, which are spectrally homogeneous regions of spatially contiguous pixels. The superpixel segmentation is combined with an unsupervised end-member extraction algorithm. Superpixel can complement per pixel classification techniques by reducing both scene-specific noise and computational complexity. step explores the entire spectrum, recognizes target mineralogies within...
Abstract. The Orbiting Carbon Observatory-2 (OCO-2) is the first National Aeronautics and Space Administration (NASA) satellite designed to measure atmospheric carbon dioxide (CO2) with accuracy, resolution, coverage needed quantify CO2 fluxes (sources sinks) on regional scales. OCO-2 was successfully launched 2 July 2014, joined 705 km Afternoon Constellation 3 August 2014. On monthly time scales, 7 12 % of these measurements are sufficiently cloud aerosol free yield estimates...
DATA REPORT article Front. Remote Sens., 26 February 2021Sec. Image Analysis and Classification https://doi.org/10.3389/frsen.2021.640034
Abstract. Since the launch of Greenhouse Gases Observing Satellite (GOSAT) in 2009, retrieval algorithms designed to infer column-averaged dry-air mole fraction carbon dioxide (XCO2) from hyperspectral near-infrared observations reflected sunlight have been greatly improved. They now generally include scattering effects clouds and aerosols, as early work found that absorption-only retrievals, which neglected these effects, often incurred unacceptably large errors, even for scenes with...
Abstract. Here, we report preliminary estimates of the column averaged carbon dioxide (CO2) dry air mole fraction, XCO2, retrieved from spectra recorded over land by Greenhouse gases Observing Satellite, GOSAT (nicknamed "Ibuki"), using retrieval methods originally developed for NASA Orbiting Carbon Observatory (OCO) mission. After screening clouds and other known error sources, these retrievals reproduce much expected structure in global XCO2 field, including its variation with latitude...
Abstract. NASA's Orbiting Carbon Observatory-2 (OCO-2) has been measuring carbon dioxide column-averaged dry air mole fractions, XCO2, in the Earth’s atmosphere for almost two years. In this paper, we describe comparisons between OCO-2 version 7Br retrievals and XCO2 estimates from OCO-2's primary ground-based validation network: Total Column Observing Network (TCCON). The retrievals, after bias correction, agree well globally with TCCON nadir, glint, target observations, median differences...