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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 343 records · Page 19

Preliminary Evaluation of the Simplified Higher Order Closure (SHOC) in the NASA Goddard Earth Observing System (GEOS)

Here we evaluate alternative planetary boundary layer (PBL) schemes in the NASA Goddard Earth Observing System (GEOS) model. The model currently calculates turbulent diffusivities with a local Richardson number-based scheme for stable layers, and a K-profile scheme with surface- and cloud-driven plumes based on Lock et al. (2000) for unstable layers. In this study, these are replaced with the TKE-based Simplified Higher Order Closure (SHOC). SHOC combines a 1.5-order turbulence closure with a double-Gaussian PDF serving as a subgrid condensation scheme. The new diffusivity calculations are paired with two new shallow mass flux schemes. First, the University of Washington shallow cumulus scheme of Park and Bretherton (2009), a buoyancy-sorting entraining-detraining bulk plume with overshooting entrainment and a TKE/CIN-based closure. Second, an Eddy Diffusivity Mass Flux (EDMF) scheme based on the multiple plume model of Suselj et al. (2013) with stochastic lateral entrainment. Global climatologies of low level temperature, humidity, and wind are evaluated against MERRA-2 and ERA-Interim reanalyses, and significant reductions in bias are seen with both mass flux schemes. The diurnal cycle over the continental United States is evaluated using MERRA-2 and an in situ network of surface Lidar profilers.

Arnold, Nathan↗

Quantum Leap: Evaluating the Feasibility of Quantum Machine Learning Using NASA Earth Observational Data

This study explores the feasibility of leveraging quantum machine learning (QML) to analyze NASA Earth Observational (EO) data for climate change research, with a particular focus on the phenomenon of ”crop frosting” which has become more prevalent due to climate change. We implemented and evaluated two QML models, the Variational Quantum Classifier (VQC) and Quantum Support Vector Classifier (QSVC), in both simulated and real quantum computing environments using a 127 qubit IBM quantum processor. Our study emphasizes the scientific rigor in comparing these quantum models with a classical Support Vector Machine (SVM) classifier, highlighting their performance in processing climate data. The results offer valuable insights into the potential scientific advantages, limitations, and scalability of QML for analyzing EO datasets, thus paving the way for more advanced climate modeling and predictive analytics using quantum computing. We showcased how Environmental Interaction Knowledge Graphs (EIKGs) and Digital Twins (DTs) can be integrated into this study. This research underscores the transformative potential of Classical and QML leveraging KGs and DT to address the multifaceted challenges posed by climate change.

Quantum Computing↗

Coordinating an Autonomous Earth-Observing Sensorweb

A system of software has been developed to coordinate the operation of an autonomous Earth-observing sensorweb. Sensorwebs are collections of sensor units scattered over large regions to gather data on spatial and temporal patterns of physical, chemical, or biological phenomena in those regions. Each sensor unit is a node in a data-gathering/ data-communication network that spans a region of interest. In this case, the region is the entire Earth, and the sensorweb includes multiple terrestrial and spaceborne sensor units. In addition to acquiring data for scientific study, the sensorweb is required to give timely notice of volcanic eruptions, floods, and other hazardous natural events. In keeping with the inherently modular nature of the sensory, communication, and data-processing hardware, the software features a flexible, modular architecture that facilitates expansion of the network, customization of conditions that trigger alarms of hazardous natural events, and customization of responses to alarms. The soft8 NASA Tech Briefs, July 2006 ware facilitates access to multiple sources of data on an event of scientific interest, enables coordinated use of multiple sensors in rapid reaction to detection of an event, and facilitates the tracking of spacecraft operations, including tracking of the acquisition, processing, and downlinking of requested data.

Sherwood, Robert↗

An Overview of the Earth Observing System MODIS Instrument and Associated Data Systems Performance

The Moderate Resolution Imaging Spectroradiometer (MODIS) on the Earth Observing System (EOS) Terra Mission began to produce data in February 2000. Now a little over 2 years from that time, the instrument continues to produce good data and products for land, oceans, and atmospheres studies are reaching or achieved maturity for science and applications studies. All subsystems of the instrument are performing as expected: the signal-to-noise (S/N) performance meets or exceeds specifications, band-to-band registration meets specifications, geodetic registration of observations is nearing 50 meters (one sigma) and the spectral bands are located where they were intended to be pre-launch and attendant gains and offsets are stable to date. Some problems with electronic noise, optical leaks, etc. have been identified and solutions to compensate or eliminate these effects have been successful. The data systems have produced a complete year or more for all data products extending from November 2000. Efforts are underway to provide data sets for the greater Earth science community and to improve access to these products at the various Distributed Active Archive Centers (DAAC's). The MODIS instrument on the EOS Aqua mission should also be expected to be in orbit and functioning in the Spring of 2002.

Salomonson, Vincent V.↗

MODIS - A global ocean facility for the Earth Observing System

A Moderate Resolution Imaging Spectrometer (MODIS) is being planned as a NASA furnished facility for the Earth Observing System (Eos). This sensor will be the primary source of optical global ocean data for a ten-year period following the Eos launch in the mid-1990's. During this period, the MODIS will survey the Earth's surface continuously once every three days in over 100 spectral bands ranging from 0.4 to 14.2 micrometers at a spatial resolution of 1 kilometer. The system is to be divided into two units, MODIS-T which consists of 64 visible and near-infrared channels and which is capable of tilting to avoid specular reflectance from the ocean surface, and MODIS-N with 31-40 spectral channels including ocean color, ocean temperature and atmospheric characterization bands. The total system is anticipated to be a powerful tool for studying global ocean productivity, dynamics and long-term trends.

Barnes, W. L.↗

Perspectives on User Engagement of Satellite Earth Observation for Water Quality Management

The management and governance of our surface waters is core to life and prosperity on our planet. However, monitoring data are not available to many potential users and the disparate nature of water bodies makes consistent monitoring across so many systems difficult. While satellite Earth observation (EO) offers solutions, there are numerous challenges that limit the use of satellite EO for water monitoring. To understand the perceptions of using satellite EO for water quality monitoring, a survey was conducted within academia and the water quality management sector. Study objectives were to assess community understanding of satellite EO water quality data, identify barriers in the adoption of satellite EO data, and analyse trust in satellite EO data. Most (40 %) participants were beginners with little understanding of satellite EO. Participants indicated problems with satellite EO data accessibility (31 %) and interpretability (26 %). Results showed a high level of trust with satellite EO data and higher trust with in-situ EO data. This study highlighted the gap between water science, applied social science, and policy. A transdisciplinary approach to managing water resources is needed to bridge water disciplines and take a key role in areas such as social issues, knowledge brokering, and translation.

water quality↗

Earth observations, overview

An overview is given of research and development activities at the Laboratory for Meteorology and Earth Sciences. Highlights of satellite techniques in earth observation missions and projects are outlined, as are remote sensing methods by aircraft overflights; most noteworthy among these is the development of multispectral scanners that monitor both the reflected infrared solar radiation and the emitted terrestrial radiation. The application of observations to the survey of environmental conditions and resource management is emphasized.

Nordberg, W.↗

Application of visible linear array technology to earth observation sensors

The present paper identifies the systems engineering aspects of applying solid-state technology to earth observations applications being traditionally performed by point (or multiple-point) detector line scanned mechanisms. It is shown that the translation from a basically serial data flow point-detector mechanically-scanned sensor to a solid state highly parallel linear-array pushbroom sensor results in minimizing mechanical complexity and maximizing electronics complexity, with increased demands upon optical performance in some applications. Technical aspects relevant to highly parallel photodiode linear-array pushbroom applications are discussed. Examples of systems engineering applications are provided.

Noll, R. E.↗

Earth observations during Space Shuttle mission STS-28 - 8-13 August 1989

An overview of the STS-28 earth observation is provided with attention given to meteorology, oceanographic phenomena, and human activity such as urban environments and related land uses. Environmental observations discussed include evidence of a monsoon, vegetation changes such as deforestation, and water pollution and eutrophication of major rivers. Particular attention is paid to atmospheric palls in both the Northern and Southern Hemispheres. Discussion of geological observations focuses on the Mount St. Helens volcano and the little-recognized landform type, the immense illuvial cone. Observation techniques include use of color infrared film and two types of polarization observations.

Whitehead, Victor S.↗

Technical report series on global modeling and data assimilation. Volume 1: Documentation of the Goddard Earth Observing System (GEOS) General Circulation Model, version 1

This technical report documents Version 1 of the Goddard Earth Observing System (GEOS) General Circulation Model (GCM). The GEOS-1 GCM is being used by NASA's Data Assimilation Office (DAO) to produce multiyear data sets for climate research. This report provides a documentation of the model components used in the GEOS-1 GCM, a complete description of model diagnostics available, and a User's Guide to facilitate GEOS-1 GCM experiments.

Suarez, Max J.↗

NASA's Autonomous Formation Flying Technology Demonstration, Earth Observing-1(EO-1)

NASA's first autonomous formation flying mission, the New Millennium Program's (NMP) Earth Observing-1 (EO-1) spacecraft, recently completed its principal goal of demonstrating advanced formation control technology. This paper provides an overview of the evolution of an onboard system that was developed originally as a ground mission planning and operations tool. We discuss the Goddard Space Flight Center s formation flying algorithm, the onboard flight design and its implementation, the interface and functionality of the onboard system, and the implementation of a Kalman filter based GPS data smoother. A number of safeguards that allow the incremental phasing in of autonomy and alleviate the potential for mission-impacting anomalies from the on- board autonomous system are discussed. A comparison of the maneuvers planned onboard using the EO-1 autonomous control system to those from the operational ground-based maneuver planning system is presented to quantify our success. The maneuvers discussed encompass reactionary and routine formation maintenance. Definitive orbital data is presented that verifies all formation flying requirements.

Folta, David↗

Taming Big Data Variety in the Earth Observing System Data and Information System

Although the volume of the remote sensing data managed by the Earth Observing System Data and Information System is formidable, an oft-overlooked challenge is the variety of data. The diversity in satellite instruments, science disciplines and user communities drives cost as much or more as the data volume. Several strategies are used to tame this variety: data allocation to distinct centers of expertise; a common metadata repository for discovery, data format standards and conventions; and services that further abstract the variations in data.

Information Systems↗

Land Boundary Conditions for the Goddard Earth Observing System Model Version 5 (GEOS-5) Climate Modeling System: Recent Updates and Data File Descriptions

The Earths land surface boundary conditions in the Goddard Earth Observing System version 5 (GEOS-5) modeling system were updated using recent high spatial and temporal resolution global data products. The updates include: (i) construction of a global 10-arcsec land-ocean lakes-ice mask; (ii) incorporation of a 10-arcsec Globcover 2009 land cover dataset; (iii) implementation of Level 12 Pfafstetter hydrologic catchments; (iv) use of hybridized SRTM global topography data; (v) construction of the HWSDv1.21-STATSGO2 merged global 30 arc second soil mineral and carbon data in conjunction with a highly-refined soil classification system; (vi) production of diffuse visible and near-infrared 8-day MODIS albedo climatologies at 30-arcsec from the period 2001-2011; and (vii) production of the GEOLAND2 and MODIS merged 8-day LAI climatology at 30-arcsec for GEOS-5. The global data sets were preprocessed and used to construct global raster data files for the software (mkCatchParam) that computes parameters on catchment-tiles for various atmospheric grids. The updates also include a few bug fixes in mkCatchParam, as well as changes (improvements in algorithms, etc.) to mkCatchParam that allow it to produce tile-space parameters efficiently for high resolution AGCM grids. The update process also includes the construction of data files describing the vegetation type fractions, soil background albedo, nitrogen deposition and mean annual 2m air temperature to be used with the future Catchment CN model and the global stream channel network to be used with the future global runoff routing model. This report provides detailed descriptions of the data production process and data file format of each updated data set.

GEOS-5↗

Earth observations from remote-sensing platforms - Outlook

Observations of the earth from remote-sensing platforms are discussed noting the NASA Earth Resources Aircraft Program, Earth Resources Technology Satellite program, and the Earth Resources Experiments Package. Techniques for geological mapping are described including automatic mapping, visual interpretation, band selection, radar, band combination, and image enhancement.

Houston, R. S.↗

Tool CREOL: Using Earth Observations to Monitor Ecosystem Health for the Preservation of Coastal Louisiana

Submerged aquatic vegetation (SAV) in Louisiana’s Breton National Wildlife Refuge (BNWR) has been steadily declining due to anthropogenic and climate induced changes, contributing to the degradation of the barrier island system. In the Chandeleur Islands region, events such as Hurricane Katrina and the Deepwater Horizon Oil Spill have reduced the barrier islands’ ability to control storm surge and have decreased seagrass extent. Seagrasses promote aquatic biodiversity, absorb excess nutrients, and reduce the rate of shoreline erosion by trapping suspended sediment. The tool for Coastal Remote Ecological Observations in Louisiana (Tool CREOL), a novel GUI, was developed using Google Earth Engine to assess historical changes to and present conditions of the Chandeleur Islands’ land cover, water quality, and seagrass extent. Developed in collaboration with the Louisiana Coastal Protection and Restoration Authority and the Louisiana Department of Natural Resources, the tool uses Earth observations acquired from NASA’s Landsat 5 TM, Landsat 7 ETM+ and Landsat 8 OLI to analyze land cover, turbidity, chlorophyll-a, and seagrass extent from 1984 to today. Tool CREOL enables continuous monitoring of the Chandeleur Islands and will aid in the identification of ideal areas for island restoration and seagrass revegetation.

Taryn Waite↗

Earth Observing System (EOS) Terra Spacecraft 120 Volt Power Subsystem: Requirements, Development and Implementation

Built by the Lockheed-Martin Corporation, the Earth Observing System (EOS) TERRA spacecraft represents the first orbiting application of a 120 Vdc high voltage spacecraft electrical power system implemented by the National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC). The EOS TERRA spacecraft's launch provided a major contribution to the NASA Mission to Planet Earth program while incorporating many state of the art electrical power system technologies to achieve its mission goals. The EOS TERRA spacecraft was designed around five state-of-the-art scientific instrument packages designed to monitor key parameters associated with the earth's climate. The development focus of the TERRA electrical power system (EPS) resulted from a need for high power distribution to the EOS TERRA spacecraft subsystems and instruments and minimizing mass and parasitic losses. Also important as a design goal of the EPS was maintaining tight regulation on voltage and achieving low conducted bus noise characteristics. This paper outlines the major requirements for the EPS as well as the resulting hardware implementation approach adopted to meet the demands of the EOS TERRA low earth orbit mission. The selected orbit, based on scientific needs, to achieve the EOS TERRA mission goals is a sun-synchronous circular 98.2degree inclination Low Earth Orbit (LEO) with a near circular average altitude of 705 kilometers. The nominal spacecraft orbit is approximately 99 minutes with an average eclipse period of about 34 minutes. The scientific goal of the selected orbit is to maintain a repeated 10:30 a.m. +/- 15 minute descending equatorial crossing which provides a fairly clear view of the earth's surface and relatively low cloud interference for the instrument observation measurements. The major EOS TERRA EPS design requirements are single fault tolerant, average orbit power delivery of 2, 530 watts with a defined minimum lifetime of five years (EOL). To meet these mission requirements, while minimizing mass and parasitic power losses, the EOS TERRA project relies on 36, 096 high efficiency Gallium Arsenide (GaAs) on Germanium solar cells adhered to a deployable flexible solar array designed to provide over 5,000 watts of power at EOL. To meet the eclipse power demands of the spacecraft, EOS TERRA selected an application of two 54-cell series connected Individual Pressure Vessel (IPV) Nickel-Hydrogen (NiH2) 50 Ampere-Hour batteries. All of the spacecraft observatory electrical power is controlled via the TERRA Power Distribution Unit (PDU) which is designed to provide main bus regulation of 120 Vdc +/- -4% at all load interfaces through the implementation of majority voter control of both the spacecraft's solar array sequential shunt unit (SSU) and the two battery bi-directional charge and discharge regulators. This paper will review the major electrical power system requirement drivers for the EOS TERRA mission as well as some of the challenges encountered during the development, testing, and implementation of the power system. In addition, spacecraft test and early on orbit performance results will also be covered.

Keys, Denney J.↗

Precise orbit determination for NASA's earth observing system using GPS (Global Positioning System)

An application of a precision orbit determination technique for NASA's Earth Observing System (EOS) using the Global Positioning System (GPS) is described. This technique allows the geometric information from measurements of GPS carrier phase and P-code pseudo-range to be exploited while minimizing requirements for precision dynamical modeling. The method combines geometric and dynamic information to determine the spacecraft trajectory; the weight on the dynamic information is controlled by adjusting fictitious spacecraft accelerations in three dimensions which are treated as first order exponentially time correlated stochastic processes. By varying the time correlation and uncertainty of the stochastic accelerations, the technique can range from purely geometric to purely dynamic. Performance estimates for this technique as applied to the orbit geometry planned for the EOS platforms indicate that decimeter accuracies for EOS orbit position may be obtainable. The sensitivity of the predicted orbit uncertainties to model errors for station locations, nongravitational platform accelerations, and Earth gravity is also presented.

Williams, B. G.↗