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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 847 records · Page 47

Remote sensing of the boundary layer over the oceans

The paper explores the possibility of remotely sensing the boundary layer structure over the oceans by means of the Nimbus 4 IR Interferometric Spectrometer (IRIS) measurements in the water vapor bands. It is found from theoretical considerations that the moderately strong spectral lines in the 9-micron water vapor window region contain useful information about the lowest layers in the atmosphere. The difference between the observed line strength and the theoretically predicted line strength provides information about the departure in the atmospheric temperature and water vapor profiles from standard conditions. The observations of METEOR oceanographic expedition over the North and South Atlantic, and the Indian Ocean expedition make it possible to model the inversion conditions. It is concluded that significant characteristics of the temperature and water vapor profiles in the boundary layer of the atmosphere can be remotely sensed using the water vapor spectral measurements over the oceans.

Prabhakara, C.↗

Applications of remote-sensing data in Alaska

Public and private agencies were introduced to the use of remotely sensed data obtained by both satellite and aircraft, and benefitted from facilities for data processing enhancement and interpretation as well as from the institute's data library. Cooperative ventures involving the performance of operational activities included assistance to the Bureau of Land Management in the suppression of wildfires; the selection of sites for power line right-of-way; the mapping of leads in sea ice; determination of portions of public lands to be allocated for small scale farming; the identification of areas for large scale farming of barley; the observation of coastal processes and sediment transport near Prudhoe Bay; the establishment of a colar infrared file of the entire state; and photomapping for geological surveys. Monitoring of the outer continental shelf environment and reindeer herds was also conducted. Institutional constraints to full utilization of satellite remote sensing in the state are explored and plans for future activites include the generation of awareness by government agencies, the training of state personnel, and improving coordination and communication with users.

Miller, J. M.↗

Energy and remote sensing

Effective implementation of the President's National Energy Plan and the Nuclear Power Policy Statement require application of the best remote sensing tools available. The potential contributions of remote sensing, particularly LANDSAT data, have yet to be clearly identified and exploited. These contributions investigated fall into the following categories: (1) exploration; (2) exploitation; (3) power plant siting; (4) environmental assessment and monitoring; and (5) transportation infrastructure.

Summers, R. A.↗

Public health applications of remote sensing of the environment, an evaluation

The available techniques were examined in the field of remote sensing (including aerial photography, infrared detection, radar, etc.) and applications to a number of problems in the wide field of public health determined. The specific areas of public health examined included: air pollution, water pollution, communicable disease, and the combined problems of urban growth and the effect of disasters on human communities. The assessment of the possible applications of remote sensing to these problems was made primarily by examination of the available literature in each field, and by interviews with health authorities, physicists, biologists, and other interested workers. Three types of programs employing remote sensors were outlined in the air pollution field: (1) proving ability of sensors to monitor pollutants at three levels of interest - point source, ambient levels in cities, and global patterns; (2) detection of effects of pollutants on the environment at local and global levels; and (3) routine monitoring.

Source record↗

Portable Laser Spectrometer for Airborne and Ground-Based Remote Sensing of Geological CO2 Emissions

A 24 kilogram, suitcase-sized, CW (Continuous Wave) Laser Remote Sensing Spectrometer (LARSS) with an approximately 2-kilometer range has been developed. It has demonstrated its flexibility in measuring both atmospheric CO2 from an airborne platform and terrestrial emission of CO2 from a remote mud volcano, Bledug Kuwu, Indonesia, from a ground-based sight. This system scans the CO2 absorption line with 20 discrete wavelengths, as opposed to the typical two-wavelength online-offline instrument. This multi-wavelength approach offers an effective quality control, bias control, and confidence estimate of measured CO2 concentrations via spectral fitting. The simplicity, ruggedness, and flexibility in the design allow for easy transportation and use on different platforms with a quick setup in some of the most challenging climatic conditions. While more refinement is needed, the results represent a stepping stone towards widespread use of active one-sided gas remote sensing in the earth sciences.

_______________________↗

[Biooptical properties of marine phytoplankton as they apply to satellite remote sensing]

This final report covers research performed over a period of 10 years from 1982 to 1992. During this time, Grant #NAGW410 was funded under three titles through a series of Supplements. The original proposal was entitled 'Photoecology, optical properties and remote sensing of warm core rings'; the second and major portion was entitled 'Continuation of studies of biooptical properties of phytoplankton and the study of mesoscale and submesoscale features using fluorescence and colorimetry'; with the final portion named 'Studies of biooptical properties of phytoplankton, with reference to identification of spectral types associated with meso- and submesoscale features in the ocean'. The focus of these projects was to try to expand our knowledge of the biooptical properties of marine phytoplankton as they apply to satellite remote sensing. We used a variety of techniques, new and old, to better measure these optical properties at appropriate scales, in some cases at the level of individual cells. We also exploited the specialized oceanic conditions that occur within certain regions and features of the ocean around the world in order to explain the tremendous variability one sees in a single remote sensing image. This document strives to provide as complete a summary as possible for this large body of work, including the pertinent publications supported by this funding.

Yentsch, Charles S.↗

New remote sensing techniques facilitate study of earth's far-flung volcanos

The study of volcanos using remote sensing is discussed. The dynamics of volcanic eruptions and the interactions between volcanos and the atmosphere and ecosphere are examined. Remote sensing equipment can effectively detect mud flows, pyroclastic falls, debris avalanches, lava flows, and hazards to aircraft from eruption plumes. Consideration is given to the use of thermal IR imaging, weather satellites, and polar-orbiting satellites to study such features as lava flow, silica content, and SO2 distribution.

Mouginis-Mark, Peter J.↗

Implementation and operation of three fractal measurement algorithms for analysis of remote-sensing data

Fractal geometry is increasingly becoming a useful tool for modeling natural phenomena. As an alternative to Euclidean concepts, fractals allow for a more accurate representation of the nature of complexity in natural boundaries and surfaces. The purpose of this paper is to introduce and implement three algorithms in C code for deriving fractal measurement from remotely sensed data. These three methods are: the line-divider method, the variogram method, and the triangular prism method. Remote-sensing data acquired by NASA's Calibrated Airborne Multispectral Scanner (CAMS) are used to compute the fractal dimension using each of the three methods. These data were obtained as a 30 m pixel spatial resolution over a portion of western Puerto Rico in January 1990. A description of the three methods, their implementation in PC-compatible environment, and some results of applying these algorithms to remotely sensed image data are presented.

Jaggi, S.↗

Applications of remote sensing in resource management in Nebraska

The project is reported for studying the application of remote sensing in land use classification and delineation of major tectonic lineaments in Nebraska. Other research reported include the use of aircraft and ERTS-1 satellite imagery in detecting and estimating the acreage of irrigated land, and the application of remote sensing in estimating evapotranspiration in the Platte River Basin.

Drew, J. V.↗

Evaluation and Application of Remotely Sensed Soil Moisture Products

Whereas in-situ measurements of soil moisture are very accurate, achieving accurate regional soil moisture estimates derived solely from point measurements is difficult because of the dependence upon the density of the gauge network and the proper upkeep of these instruments, which can be costly. Microwave remote sensing is the only technology capable of providing timely direct measurements of regional soil moisture in areas that are lacking in-situ networks. Soil moisture remote sensing technology is well established has been successfully applied in many fashions to Earth Science applications. Since the microwave emission from the soil surface has such a high dependency upon the moisture content within the soil, we can take advantage of this relationship and combined with physically-based models of the land surface, derive accurate regional estimates of the soil column water content from the microwave brightness temperature observed from satellite-based remote sensing instruments. However, there still remain many questions regarding the most efficient methodology for evaluating and applying satellite-based soil moisture estimates. As discussed below, we to use satellite-based estimates of soil moisture dynamics to improve the predictive capability of an optimized hydrologic model giving more accurate root-zone soil moisture estimates.

Bolten, J.↗

Editorial: Advanced Technologies in Remote Sensing of Aerosols and Trace Gases Special Issue

The seven papers in this special issue span a range of satellite remote-sensing applications, from characterizing near-surface aerosol pollution and SO2 concentrations (Qu et al., 2023a and Xu et al., 2023, respectively), to atmospheric column methane and cloud measurement (Karoff and Vara-Vela, 2023 and Jian et al., 2023, respectively), to the stratospheric aerosol distribution over the over Xinjiang region of China (ZiWei and Xiangling, 2023). In these efforts to advance the field, common threads are the use of various machine learning methods to extract patterns from vast amounts of satellite data, and in many cases, the integration of multiple datasets, from different sources, sometimes including models, to provide the constraints required to obtain meaningful geophysical quantities.

aerosol remote sensing↗

Remote sensing of tidal wetlands - Mapping and beyond

Remote sensing, by means of aerial photography, is an accepted method for the mapping and inventory of tidal wetlands, enjoying considerable advantages in speed, flexibility and cost per area mapped over conventional techniques. Initially employed for the identification of wetlands and their boundaries, new applications concern the effective sensing of functional processes within the wetlands environment, such as plant biomass and the production of biogenic gases. The availability of accurate hand-held radiometers has produced increased efforts to quantitatively relate remote measurements to environmental parameters for these processes, expanding the information derivable from aerial and orbital multispectral scanners.

Bartlett, D. S.↗

Preliminary Findings of Inflight Icing Field Test to Support Icing Remote Sensing Technology Assessment

NASA and the National Center for Atmospheric Research have developed an icing remote sensing technology that has demonstrated skill at detecting and classifying icing hazards in a vertical column above an instrumented ground station. This technology has recently been extended to provide volumetric coverage surrounding an airport. Building on the existing vertical pointing system, the new method for providing volumetric coverage will utilize a vertical pointing cloud radar, a multifrequency microwave radiometer with azimuth and elevation pointing, and a NEXRAD radar. The new terminal area icing remote sensing system processes the data streams from these instruments to derive temperature, liquid water content, and cloud droplet size for each examined point in space. These data are then combined to ultimately provide icing hazard classification along defined approach paths into an airport.

remote sensors↗

Passive microwave remote sensing of the ocean - A review

This paper reviews the current status of passive microwave remote sensing of the ocean. The physics of emission and instrumentation are highlighted in order to establish a relationship between the thermal emission and retrieved geophysical parameters. A discussion then follows on measurements of temperature, salinity, windspeed, etc. using passive microwave systems. These measurements are related to the accuracy and spatial resolution required by the users. The status of passive microwave remote sensing is summarized and recommendations for future research are presented.

Swift, C. T.↗

Semiconductor Reference Oscillator Development for Coherent Detection Optical Remote Sensing Applications

The NASA Earth Science Enterprise Advanced Technology Initiatives Program is supporting a program for the development of semiconductor laser reference oscillators for application to coherent optical remote sensing from Earth orbit. Local oscillators provide the frequency reference required for active spaceborne optical remote sensing concepts that involve heterodyne (coherent) detection. Two recent examples of such schemes are Doppler wind lidar and tropospheric carbon dioxide measurement by laser absorption spectrometry, both of which are being proposed at a wavelength of 2.05 microns. Frequency-agile local oscillator technology is important to such applications because of the need to compensate for large platform-induced Doppler components that would otherwise interfere with data interpretation. Development of frequency-agile local oscillator approaches has heretofore utilized the same laser material as the transmitter laser (Tm,Ho:YLF in the case of the 2.05-micron wavelength mentioned above). However, a semiconductor laser-based frequency-agile local oscillator offers considerable scope for reduced mechanical complexity and improved frequency agility over equivalent crystal laser devices, while their potentially faster tuning capability suggest the potential for greater scanning versatility. The program we report on here is specifically tasked with the development of prototype novel architecture semiconductor lasers with the power, tunability, and spectral characteristics required for coherent Doppler lidar. The baseline approach for this work is the distributed feedback (DFB) laser, in which gratings are etched into the semiconductor waveguide structures along the entire length of the laser cavity. However, typical DFB lasers at the wavelength of interest have linewidths that exhibit unacceptable growth when driven at the high currents and powers that are required for the Doppler lidar application. Suppression of this behavior by means of corrugation pitch-modulation (using a detuned central section to prevent intensity peaking in the center of the cavity) is currently under investigation to achieve the required performance goals.

distributed feedback (DFB) laser↗

The Geologic Remote Sensing Field Experiment (GRSFE): The first geology multisensor airborne campaign

The primary objective of the Geologic Remote Sensing Field Experiment (GRSFE) is to acquire relevant data for geological sites that can be used to test models for extraction of surface property information from remote sensing data for earth, Mars and Venus in support of the Earth Observing System (EOS), Mars Observer, and Magellan, respectively. Over forty scientists from eight universities and three NASA centers are participating in GRSFE which is co-sponsored by the NASA Planetary Geology and Geophysics Program and the NASA Geology Program. Highlights of the airborne campaign included the first simultaneous acquisition of Airborne Visible and Infrared Imaging Spectrometer (AVRIS) and Thermal Infrared Multispectral Scanner (TIMS) data on September 29, 1989, and acquisition of Advanced Solid-State Array Spectroradiometer (ASAS), Polarimetric Synthetic Aperture Radar (AIRSAR), and Airborne Terrain Laser Altimeter System (ATLAS) data all within three months of each other. The sites covered were Lunar Crater Volcanic Field and Fish Lake Valley in Nevada; and Cima Volcanic Field, Death Valley, and Ubehebe Crater in California. Coincident field measurements included meteorological and atmospheric measurements, visible/near-infrared and thermal spectra, and characterization of geology and vegetation cover. The GRSFE airborne and field data will be reduced to a suite of standard products and submitted, along with appropriate documentation, to the Planetary Data System (PDS) and the Pilot Land Data System (PLDS). These data will be used for a variety of investigations including paleoclimatic studies in the arid southwestern United States, and analysis of Magellan data. GRSFE data will also be used to support Mars Observer Laser Altimeter (MOLA) and Mars Rover Sample Return (MRSR) simulation studies.

Evans, Diane L.↗

The use of aircraft and satellite remote sensing of phytoplankton chlorophyll concentrations in case 2 estuarine waters of the Chesapeake Bay

Two projects using remote sensing of phytoplankton chlorophyll concentrations in the Chesapeake Bay estuary were proposed. The first project used aircraft remote sensing with a compact radiometer system developed at NASA's Goddard Space Flight Center (GSFC), the Ocean Data Acquisition System (ODAS). ODAS includes three radiometers at 460, 490, and 520 nm, an infrared temperature sensor (PRT-5), Loran-C for navigation, and a data acquisition system using a PC and mass storage device. This instrument package can be flown in light aircraft at relatively low expense, permitting regular and frequent flights. Sixteen flights with ODAS were completed using the Virginia Institute of Marine Science's De Havilland 'Beaver'. The goal was to increase spatial and temporal resolution in assaying phytoplankton pigment concentrations in the Chesapeake. At present, analysis is underway of flight data collected between March and July 1989. The second project focused on satellite data gathered with the Nimbus-7 Coastal Zone Color Scanner (CZSC) between late 1978 and mid 1986. The problem in using CZSC data for the Chesapeake Bay is that the optical characteristics of this (and many) coastal and estuarine waters are distinct from those of the open ocean for which algorithms for computing pigment concentrations were developed. The successful use of CZCS data for the estuary requires development of site-specific algorithms and analytical approaches. Of principal importance in developing site-specific procedures is the availability of in-situ data on pigment concentrations. A significant data set was acquired from EPA's Chesapeake Bay Program in Annapolis, Maryland, and clear satellite scenes are being analyzed for which same-day sea truth measurements of pigment were obtained. Both the University of Miami and GSFC Seapak systems are being used in this effort. The main finding to date is an expected one, i.e., the algorithms developed for oceanic waters are inadequate to compute pigment concentrations for the Case 2 waters of the Chesapeake Bay. One reason is the overestimation of aerosol radiances by assuming that water-leaving radiance in Band 4 of CZCS (670 nm) is zero, an assumption that is invalid for the Bay. This prompted any attempts to iterative procedures for estimating the proportion of the Band 4 radiance that is actually attributable to aerosol by estimating the water-leaving component using optical data. A cruise on the Chesapeake the week of 7 August 1989 was conducted to collect additional optical data necessary to this task.

Harding, Lawrence W., Jr.↗

Remote sensing of the asteroids

Knowledge of the compositions of the asteroids is obtained by the remote sensing of reflected and emitted radiation from what are essentially star-like points of light. Since asteroids are a remnant population of planetesimals that were never accreted into the larger planets, their compositions and properties can provide insight into the nature of planetary matter in early epochs, before most of it was physically and chemically modified by geological processes within the planets. The progress made during the past decade in learning about asteroids through remote sensing is reviewed.

Chapman, C. R.↗