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Sample records for airborne microwave remote

  1. Remote monitoring of soil moisture using airborne microwave radiometers

    NASA Technical Reports Server (NTRS)

    Kroll, C. L.

    1973-01-01

    The current status of microwave radiometry is provided. The fundamentals of the microwave radiometer are reviewed with particular reference to airborne operations, and the interpretative procedures normally used for the modeling of the apparent temperature are presented. Airborne microwave radiometer measurements were made over selected flight lines in Chickasha, Oklahoma and Weslaco, Texas. Extensive ground measurements of soil moisture were made in support of the aircraft mission over the two locations. In addition, laboratory determination of the complex permittivities of soil samples taken from the flight lines were made with varying moisture contents. The data were analyzed to determine the degree of correlation between measured apparent temperatures and soil moisture content.

  2. High altitude airborne remote sensing mission using the advanced microwave precipitation radiometer (AMPR)

    NASA Technical Reports Server (NTRS)

    Galliano, J.; Platt, R. H.; Spencer, Roy; Hood, Robbie

    1991-01-01

    The advanced microwave precipitation radiometer (AMPR) is an airborne multichannel imaging radiometer used to better understand how the earth's climate structure works. Airborne data results from the October 1990 Florida thunderstorm mission in Jacksonville, FL, are described. AMPR data on atmospheric precipitation in mesoscale storms were retrieved at 10.7, 19.35, 37.1, and 85.5 GHz onboard the ER-2 aircraft at an altitude of 20 km. AMPR's three higher-frequency data channels were selected to operate at the same frequencies as the spaceborne special sensor microwave/imager (SSM/I) presently in orbit. AMPR uses two antennas to receive the four frequencies: the lowest frequency channel uses a 9.7-in aperture lens antennas, while the three higher-frequency channels share a separate 5.3-in aperture lens antenna. The radiometer's temperature resolution performance is summarized.

  3. Soil moisture estimation by airborne active and passive microwave remote sensing: A test-bed for SMAP fusion algorithms

    NASA Astrophysics Data System (ADS)

    Montzka, Carsten; Bogena, Heye; Jagdhuber, Thomas; Hajnsek, Irena; Horn, Ralf; Reigber, Andreas; Hasan, Sayeh; Rüdiger, Christoph; Jaeger, Marc; Vereecken, Harry

    2014-05-01

    The objective of the NASA Soil Moisture Active & Passive (SMAP) mission is to provide global measurements of soil moisture and its freeze/thaw state. The SMAP launch is currently planned for 2014-2015. The SMAP measurement approach is to integrate L-band radar and L-band radiometer as a single observation system combining the respective strengths of active and passive remote sensing for enhanced soil moisture mapping. The radar and radiometer measurements can be effectively combined to derive soil moisture maps that approach the accuracy of radiometer-only retrievals, but with a higher resolution (being able to approach the radar resolution under some conditions). Aircraft and tower-based instruments will be a key part of the SMAP validation program. Here, we present an airborne campaign in the Rur catchment in Germany, in which the passive L-band system Polarimetric L-band Multi-beam Radiometer (PLMR2) and the active L-band system DLR F-SAR were flown on six dates in 2013. The flights covered the full heterogeneity of the area under investigation, i.e. all types of land cover and experimental monitoring sites. These data are used as a test-bed for the analysis of existing and development of new active-passive fusion techniques. A synergistic use of the two signals can help to decouple soil moisture effects from the effects of vegetation (or roughness) in a better way than in the case of a single instrument. In this study, we present and evaluate three approaches for the fusion of active and passive microwave records for an enhanced representation of the soil moisture status: i) estimation of soil moisture by passive sensor data and subsequent disaggregation by active sensor backscatter data, ii) disaggregation of passive microwave brightness temperature by active microwave backscatter and subsequent inversion to soil moisture, and iii) fusion of two single-source soil moisture products from radar and radiometer.

  4. Airborne Microwave Imaging of River Velocities

    NASA Technical Reports Server (NTRS)

    Plant, William J.

    2002-01-01

    The objective of this project was to determine whether airborne microwave remote sensing systems can measure river surface currents with sufficient accuracy to make them prospective instruments with which to monitor river flow from space. The approach was to fly a coherent airborne microwave Doppler radar, developed by APL/UW, on a light airplane along several rivers in western Washington state over an extended period of time. The fundamental quantity obtained by this system to measure river currents is the mean offset of the Doppler spectrum. Since this scatter can be obtained from interferometric synthetic aperture radars (INSARs), which can be flown in space, this project provided a cost effective means for determining the suitability of spaceborne INSAR for measuring river flow.

  5. NORSEX 1979 microwave remote sensing data report

    NASA Technical Reports Server (NTRS)

    Hennigar, H. F.; Schaffner, S. K.

    1982-01-01

    Airborne microwave remote sensing measurements obtained by NASA Langley Research Center in support of the 1979 Norwegian Remote Sensing Experiment (NORSEX) are summarized. The objectives of NORSEX were to investigate the capabilities of an active/passive microwave system to measure ice concentration and type in the vicinity of the marginal ice zone near Svalbard, Norway and to apply microwave techniques to the investigation of a thermal oceanic front near Bear Island, Norway. The instruments used during NORSEX include the stepped frequency microwave radiometer, airborne microwave scatterometer, precision radiation thermometer and metric aerial photography. The data are inventoried, summarized, and presented in a user-friendly format. Data summaries are presented as time-history plots which indicate when and where data were obtained as well as the sensor configuration. All data are available on nine-track computer tapes in card-image format upon request to the NASA Langley Technical Library.

  6. Microwave remote sensing of soil moisture

    NASA Technical Reports Server (NTRS)

    Shiue, J. C.; Wang, J. R.

    1988-01-01

    Knowledge of soil moisture is important to many disciplines, such as agriculture, hydrology, and meteorology. Soil moisture distribution of vast regions can be measured efficiently only with remote sensing techniques from airborne or satellite platforms. At low microwave frequencies, water has a much larger dielectric constant than dry soil. This difference manifests itself in surface emissivity (or reflectivity) change between dry and wet soils, and can be measured by a microwave radiometer or radar. The Microwave Sensors and Data Communications Branch is developing microwave remote sensing techniques using both radar and radiometry, but primarily with microwave radiometry. The efforts in these areas range from developing algorithms for data interpretation to conducting feasibility studies for space systems, with a primary goal of developing a microwave radiometer for soil moisture measurement from satellites, such as EOS or the Space Station. These efforts are listed.

  7. Applications of airborne remote sensing in atmospheric sciences research

    NASA Technical Reports Server (NTRS)

    Serafin, R. J.; Szejwach, G.; Phillips, B. B.

    1984-01-01

    This paper explores the potential for airborne remote sensing for atmospheric sciences research. Passive and active techniques from the microwave to visible bands are discussed. It is concluded that technology has progressed sufficiently in several areas that the time is right to develop and operate new remote sensing instruments for use by the community of atmospheric scientists as general purpose tools. Promising candidates include Doppler radar and lidar, infrared short range radiometry, and microwave radiometry.

  8. Microwave remote sensing from space

    NASA Technical Reports Server (NTRS)

    Carver, K. R.; Elachi, C.; Ulaby, F. T.

    1985-01-01

    Spaceborne microwave remote sensors provide perspectives of the earth surface and atmosphere which are of unique value in scientific studies of geomorphology, oceanic waves and topography, atmospheric water vapor and temperatures, vegetation classification and stress, ice types and dynamics, and hydrological characteristics. Microwave radars and radiometers offer enhanced sensitivities to the geometrical characteristics of the earth's surface and its cover, to water in all its forms - soil and vegetation moisture, ice, wetlands, oceans, and atmospheric water vapor, and can provide high-resolution imagery of the earth's surface independent of cloud cover or sun angle. A brief review of the historical development and principles of active and passive microwave remote sensing is presented, with emphasis on the unique characteristics of the information obtainable in the microwave spectrum and the value of this information to global geoscientific studies. Various spaceborne microwave remote sensors are described, with applications to geology, planetology, oceanography, glaciology, land biology, meteorology, and hydrology. A discussion of future microwave remote sensor technological developments and challenges is presented, along with a summary of future missions being planned by several countries.

  9. Airborne thermography or infrared remote sensing.

    PubMed

    Goillot, C C

    1975-01-01

    Airborne thermography is part of the more general remote sensing activity. The instruments suitable for image display are infrared line scanners. A great deal of interest has developed during the past 10 years in airborne thermal remote sensing and many applications are in progress. Infrared scanners on board a satellite are used for observation of cloud cover; airborne infrared scanners are used for forest fire detection, heat budget of soils, detecting insect attack, diseases, air pollution damage, water stress, salinity stress on vegetation, only to cite some main applications relevant to agronomy. Using this system it has become possible to get a 'picture' of our thermal environment.

  10. Greenland 1979 microwave remote sensing data catalog report, 14-15 October 1979

    NASA Technical Reports Server (NTRS)

    Hennigar, H. F.; Hirstein, W. S.; Schaffner, S. K.; Delnore, V. E.; Grantham, W. L.

    1983-01-01

    Microwave remote sensing measurements were cataloged for active and passive instruments in support of the 1979 Greenland Remote Sensing Experiment. Instruments used in this field experiment include the stepped frequency microwave radiometer (4 to 8 GHz) and the airborne microwave scatterometer (14.6 GHz). The microwave signature data are inventoried and cataloged in a user friendly format and are available on 9 track computer compatible tapes upon request.

  11. Theory of microwave remote sensing

    NASA Technical Reports Server (NTRS)

    Tsang, L.; Kong, J. A.; Shin, R. T.

    1985-01-01

    Active and passive microwave remote sensing of earth terrains is studied. Electromagnetic wave scattering and emission from stratified media and rough surfaces are considered with particular application to the remote sensing of soil moisture. Radiative transfer theory for both the random and discrete scatterer models is examined. Vector radiative transfer equations for nonspherical particles are developed for both active and passive remote sensing. Single and multiple scattering solutions are illustrated with applications to remote sensing problems. Analytical wave theory using the Dyson and Bethe-Salpeter equations is employed to treat scattering by random media. The backscattering enhancement effects, strong permittivity fluctuation theory, and modified radiative transfer equations are addressed. The electromagnetic wave scattering from a dense distribution of discrete scatterers is studied. The effective propagation constants and backscattering coefficients are calculated and illustrated for dense media.

  12. Salinity surveys using an airborne microwave radiometer

    NASA Technical Reports Server (NTRS)

    Paris, J. F.; Droppleman, J. D.; Evans, D. E.

    1972-01-01

    The Barnes PRT-5 infrared radiometer and L-band channel of the multifrequency microwave radiometer are used to survey the distribution of surface water temperature and salinity. These remote sensors were flown repetitively in November 1971 over the outflow of the Mississippi River into the Gulf of Mexico. Data reduction parameters were determined through the use of flight data obtained over a known water area. With these parameters, the measured infrared and microwave radiances were analyzed in terms of the surface temperature and salinity.

  13. Microwave remote sensing of flood inundation

    NASA Astrophysics Data System (ADS)

    Schumann, Guy J.-P.; Moller, Delwyn K.

    Flooding is one of the most costly natural disasters and thus mapping, modeling and forecasting flood events at various temporal and spatial scales is important for any flood risk mitigation plan, disaster relief services and the global (re-)insurance markets. Both computer models and observations (ground-based, airborne and Earth-orbiting) of flood processes and variables are of great value but the amount and quality of information available varies greatly with location, spatial scales and time. It is very well known that remote sensing of flooding, especially in the microwave region of the electromagnetic spectrum, can complement ground-based observations and be integrated with flood models to augment the amount of information available to end-users, decision-makers and scientists. This paper aims to provide a concise review of both the science and applications of microwave remote sensing of flood inundation, focusing mainly on synthetic aperture radar (SAR), in a variety of natural and man-made environments. Strengths and limitations are discussed and the paper will conclude with a brief account on perspectives and emerging technologies.

  14. Basic studies in microwave remote sensing

    NASA Technical Reports Server (NTRS)

    Fung, Adrian K.; Bredow, Jonathan

    1992-01-01

    Scattering models were developed in support of microwave remote sensing of earth terrains with particular emphasis on model applications to airborne Synthetic Aperture Radar measurements of forest. Practically useful surface scattering models based on a solution of a pair of integral equations including multiple scattering effects were developed. Comparisons of these models with controlled scattering measurements from statistically known random surfaces indicate that they are valid over a wide range of frequencies. Scattering models treating a forest environment as a two and three layered media were also developed. Extensive testing and comparisons were carried out with the two layered model. Further studies with the three layered model are being carried out. A volume scattering model valid for dense media such as a snow layer was also developed that shows the appropriate trend dependence with the volume fraction of scatterers.

  15. Passive Microwave Remote Sensing of Soil Moisture

    NASA Technical Reports Server (NTRS)

    Njoku, Eni G.; Entekhabi, Dara

    1994-01-01

    Microwave remote sensing provides a unique capability for direct observation of soil moisture... This Paper outlines the basic principles of the passive microwave technique for soil moisture sensing, and reviews briefly the status of current retrieval methods.

  16. Microwave remote sensing of snowpack properties

    NASA Technical Reports Server (NTRS)

    Rango, A. (Editor)

    1980-01-01

    Topic concerning remote sensing capabilities for providing reliable snow cover data and measurement of snow water equivalents are discussed. Specific remote sensing technqiues discussed include those in the microwave region of the electromagnetic spectrum.

  17. Microwave remote sensing laboratory design

    NASA Technical Reports Server (NTRS)

    Friedman, E.

    1979-01-01

    Application of active and passive microwave remote sensing to the study of ocean pollution is discussed. Previous research efforts, both in the field and in the laboratory were surveyed to derive guidance for the design of a laboratory program of research. The essential issues include: choice of radar or radiometry as the observational technique; choice of laboratory or field as the research site; choice of operating frequency; tank sizes and material; techniques for wave generation and appropriate wavelength spectrum; methods for controlling and disposing of pollutants used in the research; and pollutants other than oil which could or should be studied.

  18. Aperture synthesis concepts in microwave remote sensing of the earth

    NASA Technical Reports Server (NTRS)

    Swift, Calvin T.; Le Vine, David M.; Ruf, Christopher S.

    1991-01-01

    The application of aperture synthesis concepts, used for many years in radio astronomy to achieve high image resolution at a reasonable cost, to remote sensing technology is discussed. The electronically scanned thinned array radiometer (ESTAR) is put forward as a viable alternative to improve spatial resolution by an order of magnitude over what is presently achieved by microwave imaging systems that are collecting data from earth orbit. Future developments in airborne sensor technology and potential spacecraft application are described.

  19. Passive microwave remote sensing of salinity in coastal zones

    NASA Technical Reports Server (NTRS)

    Swift, Calvin T.; Blume, Hans-Juergen C.; Kendall, Bruce M.

    1987-01-01

    The theory of measuring coastal-zone salinity from airborne microwave radiometers is developed. The theory, as presented, shows that precision measurements of salinity favor the lower microwave frequencies. To this end, L- and S-Band systems were built, and the flight results have shown that accuracies of at least one part per thousand were achieved.The aircraft results focus on flights conducted over the Chesapeake Bay and the mouth of the Savanna River off the Georgia Coast. This paper presents no new work, but rather summarizes the capabilities of the remote sensing technique.

  20. Soil moisture mapping by ground and airborne microwave radiometry

    NASA Technical Reports Server (NTRS)

    Poe, G.; Edgerton, A. T.

    1972-01-01

    Extensive ground-based and airborne investigations were undertaken in conjunction with laboratory dielectric measurements of soils and analytical modeling. Radiometric measurements were made in the vicinity of Phoenix, Arizona at observational wavelengths ranging from 0.81 to 21 cm. Ground experiments were conducted with a microwave field laboratory and airborne measurements were obtained from a CV-990 aircraft. Research activities were focused on establishing basic relationships between microwave emission and the distribution of moisture.

  1. Retrieval of Atmospheric Temperature from Airborne Microwave Radiometer Observations

    NASA Astrophysics Data System (ADS)

    Xu, Jian; Schreier, Franz; Kenntner, Mareike; Fix, Andreas; Trautmann, Thomas

    2015-06-01

    Atmospheric temperature is a key geophysical parameter associated with fields such as meteorology, climatology, or photochemistry. There exist several techniques to measure temperature profiles. In the case of microwave remote sensing, the vertical temperature profile can be estimated from thermal emission lines of molecular oxygen. The MTP (Microwave Temperature Profiler) instrument is an airborne radiometer developed at the Jet Propulsion Laboratory (JPL), United States. The instrument passively measures natural thermal emission from oxygen lines at 3 frequencies and at a selection of 10 viewing angles (from near zenith to near nadir). MTP has participated in hundreds of flights, including on DLR’s Falcon and HALO aircrafts. These flights have provided data of the vertical temperature distribution from the troposphere to the lower stratosphere with a good temporal and spatial resolution. In this work, we present temperature retrievals based on the Tikhonov-type regularized nonlinear least squares fitting method. In particular, Jacobians (i.e. temperature derivatives) are evaluated by means of automatic differentiation. The retrieval performance from the MTP measurements is analyzed by using synthetic data. Besides, the vertical sensitivity of the temperature retrieval is studied by weighting functions characterizing the sensitivity of the transmission at different frequencies with respect to changes of altitude levels.

  2. Beaufort/Bering 1979 microwave remote sensing data catalog report, 14-24 March 1979

    NASA Technical Reports Server (NTRS)

    Hirstein, W. S.; Hennigar, H. F.; Schaffner, S. K.; Delnore, V. E.; Grantham, W. L.

    1983-01-01

    The airborne microwave remote sending measurements obtained by the Langley Research Center in support of the 1979 Sea-Ice Radar Experiment (SIRE) in the Beaufort and Bering Seas are discussed. The remote sensing objective of SIRE was to define correlations between both active and passive microwave signatures and ice phenomena assocated with practical applications in the Arctic. The instruments used by Langley during SIRE include the stepped frequency microwave radiometer (SFMR), the airborne microwave scatterometer (AMSCAT), the precision radiation thermometer (PRT-5), and metric aerial photography. Remote sensing data are inventoried and cataloged in a user-friendly format. The data catalog is presented as time-history plots when and where data were obtained as well as the sensor configuration.

  3. Microwave remote sensing of ionized air.

    SciTech Connect

    Liao, S.; Gopalsami, N.; Heifetz, A.; Elmer, T.; Fiflis, P.; Koehl, E. R.; Chien, H. T.; Raptis, A. C.

    2011-07-01

    We present observations of microwave scattering from ambient room air ionized with a negative ion generator. The frequency dependence of the radar cross section of ionized air was measured from 26.5 to 40 GHz (Ka-band) in a bistatic mode with an Agilent PNA-X series (model N5245A) vector network analyzer. A detailed calibration scheme is provided to minimize the effect of the stray background field and system frequency response on the target reflection. The feasibility of detecting the microwave reflection from ionized air portends many potential applications such as remote sensing of atmospheric ionization and remote detection of radioactive ionization of air.

  4. Low cost airborne microwave landing system receiver, task 3

    NASA Technical Reports Server (NTRS)

    Hager, J. B.; Vancleave, J. R.

    1979-01-01

    Work performed on the low cost airborne Microwave Landing System (MLS) receiver is summarized. A detailed description of the prototype low cost MLS receiver is presented. This detail includes block diagrams, schematics, board assembly drawings, photographs of subassemblies, mechanical construction, parts lists, and microprocessor software. Test procedures are described and results are presented.

  5. Passive Microwave Remote Sensing of Soil Moisture

    NASA Technical Reports Server (NTRS)

    Njoku, Eni G.; Entekhabi, Dara

    1996-01-01

    Microwave remote sensing provides a unique capability for direct observation of soil moisture. Remote measurements from space afford the possibility of obtaining frequent, global sampling of soil moisture over a large fraction of the Earth's land surface. Microwave measurements have the benefit of being largely unaffected by cloud cover and variable surface solar illumination, but accurate soil moisture estimates are limited to regions that have either bare soil or low to moderate amounts of vegetation cover. A particular advantage of passive microwave sensors is that in the absence of significant vegetation cover soil moisture is the dominant effect on the received signal. The spatial resolutions of passive Microwave soil moisture sensors currently considered for space operation are in the range 10-20 km. The most useful frequency range for soil moisture sensing is 1-5 GHz. System design considerations include optimum choice of frequencies, polarizations, and scanning configurations, based on trade-offs between requirements for high vegetation penetration capability, freedom from electromagnetic interference, manageable antenna size and complexity, and the requirement that a sufficient number of information channels be available to correct for perturbing geophysical effects. This paper outlines the basic principles of the passive microwave technique for soil moisture sensing, and reviews briefly the status of current retrieval methods. Particularly promising are methods for optimally assimilating passive microwave data into hydrologic models. Further studies are needed to investigate the effects on microwave observations of within-footprint spatial heterogeneity of vegetation cover and subsurface soil characteristics, and to assess the limitations imposed by heterogeneity on the retrievability of large-scale soil moisture information from remote observations.

  6. Microwave remote sensing of soil water content

    NASA Technical Reports Server (NTRS)

    Cihlar, J.; Ulaby, F. T.

    1975-01-01

    Microwave remote sensing of soils to determine water content was considered. A layered water balance model was developed for determining soil water content in the upper zone (top 30 cm), while soil moisture at greater depths and near the surface during the diurnal cycle was studied using experimental measurements. Soil temperature was investigated by means of a simulation model. Based on both models, moisture and temperature profiles of a hypothetical soil were generated and used to compute microwave soil parameters for a clear summer day. The results suggest that, (1) soil moisture in the upper zone can be predicted on a daily basis for 1 cm depth increments, (2) soil temperature presents no problem if surface temperature can be measured with infrared radiometers, and (3) the microwave response of a bare soil is determined primarily by the moisture at and near the surface. An algorithm is proposed for monitoring large areas which combines the water balance and microwave methods.

  7. Microwave remote sensing of snowpacks

    NASA Technical Reports Server (NTRS)

    Stiles, W. H.; Ulaby, F. T.

    1980-01-01

    The interaction mechanisms responsible for the microwave backscattering and emission behavior of snow were investigated, and models were developed relating the backscattering coefficient (sigma) and apparent temperature (T) to the physical parameters of the snowpack. The microwave responses to snow wetness, snow water equivalent, snow surface roughness, and to diurnal variations were investigated. Snow wetness was shown to have an increasing effect with increasing frequency and angle of incidence for both active and passive cases. Increasing snow wetness was observed to decrease the magnitude sigma and increase T. Snow water equivalent was also observed to exhibit a significant influence sigma and T. Snow surface configuration (roughness) was observed to be significant only for wet snow surface conditions. Diurnal variations were as large as 15 dB for sigma at 35 GHz and 120 K for T at 37 GHz. Simple models for sigma and T of a snowpack scene were developed in terms of the most significant ground-truth parameters. The coefficients for these models were then evaluated; the fits to the sigma and T measurements were generally good. Finally, areas of needed additional observations were outlined and experiments were specified to further the understanding of the microwave-snowpack interaction mechanisms.

  8. Airborne antenna polarization study for the microwave landing system

    NASA Technical Reports Server (NTRS)

    Gilreath, M. C.

    1976-01-01

    The feasibility of the microwave landing system (MLS) airborne antenna pattern coverage requirements are investigated for a large commercial aircraft using a single omnidirectional antenna. Omnidirectional antennas having vertical and horizontal polarizations were evaluated at several different station locations on a one-eleventh scale model Boeing 737 aircraft. The results obtained during this experimental program are presented which include principal plane antenna patterns and complete volumetric coverage plots.

  9. Airborne Remote Sensing for Earth Science Applications

    NASA Technical Reports Server (NTRS)

    Aubrey, Andrew

    2013-01-01

    Topics covered include: Passive Remote Sensing Methods, Imaging Spectroscopy Approach, Remote Measurement via Spectral Fitting, Imaging Spectroscopy Mapping Wetland Dominants 2010 LA (AVIRIS), Deepwater Horizon Response I, Deepwater Horizon Response II, AVIRIS Ocean Color Studies.

  10. Assessment of Superflux relative to remote sensing. [airborne remote sensing of the Chesapeake Bay plume and shelf regions

    NASA Technical Reports Server (NTRS)

    Campbell, J. W.

    1981-01-01

    The state-of-the-art advancements in remote sensor technology due to the Superflux program are examined. Three major individual sensor technologies benefitted from the program: laser fluorosensors, optical-range scanners, and passive microwave sensors. Under Superflux, convincing evidence was obtained that the airborne oceanographic lidar fluorosensor can map chlorophyll, i.e., is linear, over a wide range from less than 0.5 to 5.0 mg/cu m. The lidar oceanographic probe dual-excitation concept for addressing phytoplankton color group composition was also demonstrated convincingly. Algorithm development, real time capabilities, and multisensor integration are also addressed.

  11. Microwave remote sensing: Active and passive. Volume 1 - Microwave remote sensing fundamentals and radiometry

    NASA Technical Reports Server (NTRS)

    Ulaby, F. T.; Moore, R. K.; Fung, A. K.

    1981-01-01

    The three components of microwave remote sensing (sensor-scene interaction, sensor design, and measurement techniques), and the applications to geoscience are examined. The history of active and passive microwave sensing is reviewed, along with fundamental principles of electromagnetic wave propagation, antennas, and microwave interaction with atmospheric constituents. Radiometric concepts are reviewed, particularly for measurement problems for atmospheric and terrestrial sources of natural radiation. Particular attention is given to the emission by atmospheric gases, clouds, and rain as described by the radiative transfer function. Finally, the operation and performance characteristics of radiometer receivers are discussed, particularly for measurement precision, calibration techniques, and imaging considerations.

  12. Airborne remote sensing for Deepwater Horizon oil spill emergency response

    NASA Astrophysics Data System (ADS)

    Kroutil, Robert T.; Shen, Sylvia S.; Lewis, Paul E.; Miller, David P.; Cardarelli, John; Thomas, Mark; Curry, Timothy; Kudaraskus, Paul

    2010-08-01

    On April 28, 2010, the Environmental Protection Agency's (EPA) Airborne Spectral Photometric Environmental Collection Technology (ASPECT) aircraft was deployed to Gulfport, Mississippi to provide airborne remotely sensed air monitoring and situational awareness data and products in response to the Deepwater Horizon oil rig disaster. The ASPECT aircraft was released from service on August 9, 2010 after having flown over 75 missions that included over 250 hours of flight operation. ASPECT's initial mission responsibility was to provide air quality monitoring (i.e., identification of vapor species) during various oil burning operations. The ASPECT airborne wide-area infrared remote sensing spectral data was used to evaluate the hazard potential of vapors being produced from open water oil burns near the Deepwater Horizon rig site. Other significant remote sensing data products and innovations included the development of an advanced capability to correctly identify, locate, characterize, and quantify surface oil that could reach beaches and wetland areas. This advanced identification product provided the Incident Command an improved capability to locate surface oil in order to improve the effectiveness of oil skimmer vessel recovery efforts directed by the US Coast Guard. This paper discusses the application of infrared spectroscopy and multispectral infrared imagery to address significant issues associated with this national crisis. More specifically, this paper addresses the airborne remote sensing capabilities, technology, and data analysis products developed specifically to optimize the resources and capabilities of the Deepwater Horizon Incident Command structure personnel and their remediation efforts.

  13. Microwave remote sensing of soil moisture

    NASA Technical Reports Server (NTRS)

    Schmugge, T. J.

    1984-01-01

    Because of the large contrast between the dielectric constant of liquid water and that of dry soil at microwave wavelength, there is a strong dependence of the thermal emission and radar backscatter from the soil on its moisture content. This dependence provides a means for the remote sensing of the moisture content in a surface layer approximately 5 cm thick. The feasibility of these techniques is demonstrated from field, aircraft and spacecraft platforms. The soil texture, surface roughness, and vegetative cover affect the sensitivity of the microwave response to moisture variations with vegetation being the most important. It serves as an attenuating layer which can totally obscure the surface. Research indicates that it is possible to obtain five or more levels of moisture discrimination and that a mature corn crop is the limiting vegetation situation.

  14. Microwave Remote Sensing of Soil Moisture

    NASA Technical Reports Server (NTRS)

    Schmugge, T. J.

    1985-01-01

    Because of the large contrast between the dielectric constant of liquid water and that of dry soil at microwave wavelength, there is a strong dependence of the thermal emission and radar backscatter from the soil on its moisture content. This dependence provides a means for the remote sensing of the moisture content in a surface layer approximately 5 cm thick. The feasibility of these techniques is demonstrated from field, aircraft and spacecraft platforms. The soil texture, surface roughness, and vegetative cover affect the sensitivity of the microwave response to moisture variations with vegetation being the most important. It serves as an attenuating layer which can totally obscure the surface. Research indicates that it is possible to obtain five or more levels of moisture discrimination and that a mature corn crop is the limiting vegetation situation.

  15. Remote sensing using an airborne biosensor

    SciTech Connect

    Ligler, F.S.; Anderson, G.P.; Davidson, P.T.; Stenger, D.A.; Ives, J.T.; King, K.D.; Page, G.; Whelan, J.P.

    1998-08-15

    There is no current method for remote identification of aerosolized bacteria. In particular, such a capability is required to warn of a biological warfare attack prior to human exposure. A fiber optic biosensor, capable of running four simultaneous immunoassays, was integrated with an automated fluidics unit, a cyclone-type air sampler, a radio transceiver, and batteries on a small, remotely piloted airplane capable of carrying a 4.5-kg payload. The biosensor system was able to collect aerosolized bacteria in flight, identify them, and transmit the data to the operator on the ground. The results demonstrate the feasibility of integrating a biosensor into a portable, remotely operated system for environmental analysis.

  16. Airborne microwave measurements of the southern Greenland ice sheet

    SciTech Connect

    Swift, C.T.; Hayes, P.S.; Herd, J.S.; Jones, W.L.; Delmore, V.E.

    1985-02-01

    Microwave remote sensing measurements were collected over Greenland with the NASA C-130 aircraft used as a platform. The principal instruments were a C band radiometer and an X band scatterometer, which simultaneously collected both active and passive microwave remote sensing data. The data collected fully support the conclusions drawn by others that volume scattering from subsurface ice lenses and glands is the major influence on microwave signature. Both thermal emission and radar backscattering results are self-consistent with rather simple theories of volume scattering. The remote sensing measurements also provide a relative measure of the number density of scatterers; however, additional theoretical work is required to establish the cross section per scatterer in order to measure absolute number density. Along this avenue of thought, the data rule out Rayleigh scattering and strongly support a high frequency model. The measured anisotropy over the ice cap appears to be a new observation, and future exploitation of remote sensing techniques may provide information relating to the average shape of subsurface patterns and information relative to glacial flow. 14 references, 10 figures.

  17. Microwave remote sensing and radar polarization signatures of natural fields

    NASA Technical Reports Server (NTRS)

    Mo, Tsan

    1989-01-01

    Theoretical models developed for simulation of microwave remote sensing of the Earth surface from airborne/spaceborne sensors are described. Theoretical model calculations were performed and the results were compared with data of field measurements. Data studied included polarimetric images at the frequencies of P band, L band, and C band, acquired with airborne polarimeters over a agricultural field test site. Radar polarization signatures from bare soil surfaces and from tree covered fields were obtained from the data. The models developed in this report include: (1) Small perturbation model of wave scatterings from randomly rough surfaces, (2) Physical optics model, (3) Geometrical optics model, and (4) Electromagnetic wave scattering from dielectric cylinders of finite lengths, which replace the trees and branches in the modeling of tree covered field. Additionally, a three-layer emissivity model for passive sensing of a vegetation covered soil surface is also developed. The effects of surface roughness, soil moisture contents, and tree parameters on the polarization signatures were investigated.

  18. An airborne remote sensing system for urban air quality

    NASA Technical Reports Server (NTRS)

    Duncan, L. J.; Friedman, E. J.; Keitz, E. L.; Ward, E. A.

    1974-01-01

    Several NASA sponsored remote sensors and possible airborne platforms were evaluated. Outputs of dispersion models for SO2 and CO pollution in the Washington, D.C. area were used with ground station data to establish the expected performance and limitations of the remote sensors. Aircraft/sensor support requirements are discussed. A method of optimum flight plan determination was made. Cost trade offs were performed. Conclusions about the implementation of various instrument packages as parts of a comprehensive air quality monitoring system in Washington are presented.

  19. Assessing Scale Effects on Snow Water Equivalent Retrievals Using Airborne and Spaceborne Passive Microwave Data

    NASA Astrophysics Data System (ADS)

    Derksen, C.; Walker, A.; Goodison, B.

    2003-12-01

    The Climate Research Branch (CRB) of the Meteorological Service of Canada (MSC) has a long-standing research program focused on the development of methods to retrieve snow cover information from passive microwave satellite data for Canadian regions. Algorithms that derive snow water equivalent (SWE) have been developed by CRB and are used to operationally generate SWE information over landscape regions including prairie, boreal forest, and taiga. New multi-scale research datasets were acquired in Saskatchewan, Canada during February 2003 to quantify the impact of spatially heterogeneous land cover and snowpack properties on passive microwave SWE retrievals. MSC microwave radiometers (6.9, 19, 37, and 85 GHz) were flown on the National Research Council (NRC) Twin Otter aircraft at two flying heights along a grid of flight lines, covering a 25 by 25 km study area centered on the Old Jack Pine Boreal Ecosystem Research and Monitoring Site (BERMS). Spaceborne Special Sensor Microwave/Imager (SSM/I) and Advanced Microwave Scanning Radiometer (AMSR-E) brightness temperatures were also acquired for this region. SWE was derived for all passive microwave datasets using the CRB land cover sensitive algorithm suite. An intensive, coincident ground sampling program characterized in situ snow depth, density, water equivalent and pack structure using a land cover based sampling scheme to isolate the variability in snow cover parameters within and between forest stands and land cover types, and within a single spaceborne passive microwave grid cell. The passive microwave data sets that are the focus of this investigation cover a range of spatial resolutions from 100-150 m for the airborne data to 10 km (AMSR-E) and 25 km (SSM/I) for the satellite data, providing the opportunity to investigate and compare microwave emission characteristics, SWE retrievals and land cover effects at different spatial scales. Initial analysis shows that the small footprint airborne passive microwave

  20. ARE AIRBORNE CONTAMINANTS A RISK FACTOR TO AQUATIC ECOSYSTEMS IN REMOTE WESTERN NATIONAL PARKS (USA)

    EPA Science Inventory

    The Western Airborne Contaminants Assessment Project (WACAP) was initiated in 2002 by the National Park Service to determine if airborne contaminants were having an impact on remote western ecosystems. Multiple sample media (snow, water, sediment, fish and terrestrial vegetation...

  1. [Remote sensing of atmospheric trace gas by airborne passive FTIR].

    PubMed

    Gao, Min-quang; Liu, Wen-qing; Zhang, Tian-shu; Liu, Jian-guo; Lu, Yi-huai; Wang, Ya-ping; Xu, Liang; Zhu, Jun; Chen, Jun

    2006-12-01

    The present article describes the details of aviatic measurement for remote sensing trace gases in atmosphere under various surface backgrounds with airborne passive FTIR. The passive down viewing and remote sensing technique used in the experiment is discussed. The method of acquiring atmospheric trace gases infrared characteristic spectra in complicated background and the algorithm of concentration retrieval are discussed. The concentrations of CO and N2O of boundary-layer atmosphere in experimental region below 1000 m are analyzed quantitatively. This measurement technique and the data analysis method, which does not require a previously measured background spectrum, allow fast and mobile remote detection and identification of atmosphere trace gas in large area, and also can be used for urgent monitoring of pollution accidental breakout.

  2. Comparison between laboratory and airborne BRDF measurements for remote sensing

    NASA Astrophysics Data System (ADS)

    Georgiev, Georgi T.; Gatebe, Charles K.; Butler, James J.; King, Michael D.

    2006-08-01

    Samples from soil and leaf litter were obtained at a site located in the savanna biome of South Africa (Skukuza; 25.0°S, 31.5°E) and their bidirectional reflectance distribution functions (BRDF) were measured using the out-of-plane scatterometer located in the National Aeronautics and Space Administration's (NASA's) Goddard Space Flight Center (GSFC) Diffuser Calibration Facility (DCaF). BRDF was measured using P and S incident polarized light over a range of incident and scatter angles. A monochromator-based broadband light source was used in the ultraviolet (uv) and visible (vis) spectral ranges. The diffuse scattered light was collected using an uv-enhanced silicon photodiode detector with output fed to a computer-controlled lock-in amplifier. Typical measurement uncertainties of the reported laboratory BRDF measurements are found to be less than 1% (k=1). These laboratory results were compared with airborne measurements of BRDF from NASA's Cloud Absorption Radiometer (CAR) instrument over the same general site where the samples were obtained. This study presents preliminary results of the comparison between these laboratory and airborne BRDF measurements and identifies areas for future laboratory and airborne BRDF measurements. This paper presents initial results in a study to try to understand BRDF measurements from laboratory, airborne, and satellite measurements in an attempt to improve the consistency of remote sensing models.

  3. Airborne microwave Doppler measurements of ocean wave directional spectra

    NASA Technical Reports Server (NTRS)

    Plant, W. J.; Keller, W. C.; Reeves, A. B.; Uliana, E. A.; Johnson, J. W.

    1987-01-01

    A technique is presented for measuring ocean wave directional spectra from aircraft using microwave Doppler radar. The technique involves backscattering coherent microwave radiation from a patch of sea surface which is small compared to dominant ocean wavelengths in the antenna look direction, and large compared to these lengths in the perpendicular (azimuthal) direction. The mean Doppler shift of the return signal measured over short time intervals is proportional to the mean sea surface velocity of the illuminated patch. Variable sea surface velocities induced by wave motion therefore produce time-varying Doppler shifts in the received signal. The large azimuthal dimension of the patch implies that these variations must be produced by surface waves traveling near the horizontal antenna look direction thus allowing determination of the direction of wave travel. Linear wave theory is used to convert the measured velocities into ocean wave spectral densities. Spectra measured simultaneously with this technique and two laser profilometers, and nearly simultaneous with this technique and two laser profilometers, and nearly simultaneous with a surface buoy, are presented. Applications and limitations of this airborne Doppler technique are discussed.

  4. Automation of hyperspectral airborne remote sensing data processing

    NASA Astrophysics Data System (ADS)

    Kozoderov, V. V.; Egorov, V. D.

    2014-12-01

    An automated system is proposed for discriminating the spectral radiances registered by the hyperspectral airborne instruments based on average spectra and their interclass variability while distinguishing pixels related to the illuminated and shaded elements of the crown trees for various species and ages. Maps of the ground-based inventory for the selected area of airborne remote sensing are used as prior information. The system automatically forms databases of the selected classes of objects using the contours of these objects drawn on the image under processing. An opportunity to distinguish these classes is demonstrated in the red edge region of the spectra transition from the chlorophyll spectral band to the maximum of the spectral vegetation reflectivity.

  5. Microwave Remote Sensing and the Cold Land Processes Field Experiment

    NASA Technical Reports Server (NTRS)

    Kim, Edward J.; Cline, Don; Davis, Bert; Hildebrand, Peter H. (Technical Monitor)

    2001-01-01

    -oriented understanding, land surface models and microwave remote sensing. The experimental design is a multi-sensor, multi-scale (1-ha to 160,000 km ^ {2}) approach to providing the comprehensive data set necessary to address several experiment objectives. A description focusing on the microwave remote sensing components (ground, airborne, and spaceborne) of the experiment will be presented.

  6. Modular airborne remote sampling and sensing system (MARSSS)

    SciTech Connect

    Woods, R.O.

    1982-04-01

    Sandia is developing a modular airborne instrumentation system for the Environmental Protection Agency. This system will allow flexibility in the choice of instruments by standardizing mountings, power supplies and sampling modes. The objective is to make it possible to perform aerial surveys from chartered aircraft that have not been adapted in a more than superficial manner. It will also allow the experimenter to tailor his choice of instruments to the specific problem. Since the equipment will have a stand-alone capability, it can be applied to other problems such as long-term unattended use at remote locations or in toxic or otherwise hazardous environments.

  7. Microwave remote sensing from space for earth resource surveys

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The concepts of radar remote sensing and microwave radiometry are discussed and their utility in earth resource sensing is examined. The direct relationship between the character of the remotely sensed data and the level of decision making for which the data are appropriate is considered. Applications of active and a passive microwave sensing covered include hydrology, land use, mapping, vegetation classification, environmental monitoring, coastal features and processes, geology, and ice and snow. Approved and proposed microwave sensors are described and the use of space shuttle as a development platform is evaluated.

  8. TCR backscattering characterization for microwave remote sensing

    NASA Astrophysics Data System (ADS)

    Riccio, Giovanni; Gennarelli, Claudio

    2014-05-01

    A Trihedral Corner Reflector (TCR) is formed by three mutually orthogonal metal plates of various shapes and is a very important scattering structure since it exhibits a high monostatic Radar Cross Section (RCS) over a wide angular range. Moreover it is a handy passive device with low manufacturing costs and robust geometric construction, the maintenance of its efficiency is not difficult and expensive, and it can be used in all weather conditions (i.e., fog, rain, smoke, and dusty environment). These characteristics make it suitable as reference target and radar enhancement device for satellite- and ground-based microwave remote sensing techniques. For instance, TCRs have been recently employed to improve the signal-to-noise ratio of the backscattered signal in the case of urban ground deformation monitoring [1] and dynamic survey of civil infrastructures without natural corners as the Musmeci bridge in Basilicata, Italy [2]. The region of interest for the calculation of TCR's monostatic RCS is here confined to the first quadrant containing the boresight direction. The backscattering term is presented in closed form by evaluating the far-field scattering integral involving the contributions related to the direct illumination and the internal bouncing mechanisms. The Geometrical Optics (GO) laws allow one to determine the field incident on each TCR plate and the patch (integration domain) illuminated by it, thus enabling the use of a Physical Optics (PO) approximation for the corresponding surface current densities to consider for integration on each patch. Accordingly, five contributions are associated to each TCR plate: one contribution is due to the direct illumination of the whole internal surface; two contributions originate by the impinging rays that are simply reflected by the other two internal surfaces; and two contributions are related to the impinging rays that undergo two internal reflections. It is useful to note that the six contributions due to the

  9. Microwave Temperature Profiler Mounted in a Standard Airborne Research Canister

    NASA Technical Reports Server (NTRS)

    Mahoney, Michael J.; Denning, Richard F.; Fox, Jack

    2009-01-01

    Many atmospheric research aircraft use a standard canister design to mount instruments, as this significantly facilitates their electrical and mechanical integration and thereby reduces cost. Based on more than 30 years of airborne science experience with the Microwave Temperature Profiler (MTP), the MTP has been repackaged with state-of-the-art electronics and other design improvements to fly in one of these standard canisters. All of the controlling electronics are integrated on a single 4 5-in. (.10 13- cm) multi-layer PCB (printed circuit board) with surface-mount hardware. Improved circuit design, including a self-calibrating RTD (resistive temperature detector) multiplexer, was implemented in order to reduce the size and mass of the electronics while providing increased capability. A new microcontroller-based temperature controller board was designed, providing better control with fewer components. Five such boards are used to provide local control of the temperature in various areas of the instrument, improving radiometric performance. The new stepper motor has an embedded controller eliminating the need for a separate controller board. The reference target is heated to avoid possible emissivity (and hence calibration) changes due to moisture contamination in humid environments, as well as avoiding issues with ambient targets during ascent and descent. The radiometer is a double-sideband heterodyne receiver tuned sequentially to individual oxygen emission lines near 60 GHz, with the line selection and intermediate frequency bandwidths chosen to accommodate the altitude range of the aircraft and mission.

  10. Remote sensing capabilities of the GEO-CAPE airborne simulator

    NASA Astrophysics Data System (ADS)

    Kowalewski, Matthew G.; Janz, Scott J.

    2014-09-01

    The Geostationary Coastal and Air Pollution Events (GEO-CAPE) Airborne Simulator (GCAS) was designed and built at the NASA Goddard Space Flight Center (GSFC) as a technology demonstration instrument for the atmospheric science study group of GEO-CAPE and potential validation instrument for NASA's Tropospheric Emissions: Monitoring Pollution (TEMPO) mission. GCAS was designed to make high altitude remote sensing observations of tropospheric and boundary layer pollutants, coastal and ocean water leaving radiances, and visible imagery for cloud and surface information. The instrument has participated in one flight campaign in Houston, TX as part of the Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality (DISCOVER-AQ) in September 2013. An overview of the instrument's design, characterization, and preliminary slant column retrievals of nitrogen dioxide (NO2) and ozone (O3) during the DISCOVER-AQ campaign will be provided in this paper.

  11. Multiresolution processing for fractal analysis of airborne remotely sensed data

    NASA Technical Reports Server (NTRS)

    Jaggi, S.; Quattrochi, D.; Lam, N.

    1992-01-01

    Images acquired by NASA's Calibrated Airborne Multispectral Scanner are used to compute the fractal dimension as a function of spatial resolution. Three methods are used to determine the fractal dimension: Shelberg's (1982, 1983) line-divider method, the variogram method, and the triangular prism method. A description of these methods and the result of applying these methods to a remotely-sensed image is also presented. The scanner data was acquired over western Puerto Rico in January, 1990 over land and water. The aim is to study impacts of man-induced changes on land that affect sedimentation into the near-shore environment. The data were obtained over the same area at three different pixel sizes: 10 m, 20 m, and 30 m.

  12. Airborne remote sensing of coal waste and acid mine drainage

    SciTech Connect

    Kim, K.E.; Lee, T.S.

    1996-07-01

    High resolution airborne remote sensing data, spatial resolution of 2m X 2m, were used to study the stream quality degradation due to the coal mines in Taebaek city, one of the major coalfields in Korea. In order to circumvent the severe topographic effect and small scale of the water stream, principal components with the least variances were utilized. They showed the subtle details in the image that were obscured by higher contrast due to the topographic effect. Through maximum likelihood classification of those components, yellowboy and mine waste could be effectively identified. Areas affected by acid mine drainage and mine waste could be also located by identifying areas of dead or dying vegetation using vegetation index map.

  13. Second International Airborne Remote Sensing Conference and Exhibition

    NASA Technical Reports Server (NTRS)

    1996-01-01

    cloud cover analysis, Quadantid meteor shower studies, extra-solar far infrared ionic structure lines measurement, Cape Kennedy launch support, and studies in air pollution, The Products and Services Exhibit showcased new sensor and image processing technologies, aircraft data collection services, unmanned vehicle technology, platform equipment, turn-key services, software a workstations, GPS services, publications, and processing and integration systems by 58 exhibitors. The participation of aircraft users and crews provided unique dialogue between those who plan data collection a operate the remote sensing technology, and those who supply the data processing and integration equipment. Research results using hyperspectral imagery, radar and optical sensors, lidar, digital aerial photography, a integrated systems were presented. Major research and development programs and campaigns we reviewed, including CNR's LARA Project and European Space Agency's 1991-1995 Airborne Campaign. The pre-conference short courses addressed airborne video, photogrammetry, hyperspectral data analysis, digital orthophotography, imagery and GIS integration, IFSAR, GPS, and spectrometer calibration.

  14. Remote sensing of soil moisture using airborne hyperspectral data

    USGS Publications Warehouse

    Finn, Michael P.; Lewis, Mark (David); Bosch, David D.; Giraldo, Mario; Yamamoto, Kristina H.; Sullivan, Dana G.; Kincaid, Russell; Luna, Ronaldo; Allam, Gopala Krishna; Kvien, Craig; Williams, Michael S.

    2011-01-01

    Landscape assessment of soil moisture is critical to understanding the hydrological cycle at the regional scale and in broad-scale studies of biophysical processes affected by global climate changes in temperature and precipitation. Traditional efforts to measure soil moisture have been principally restricted to in situ measurements, so remote sensing techniques are often employed. Hyperspectral sensors with finer spatial resolution and narrow band widths may offer an alternative to traditional multispectral analysis of soil moisture, particularly in landscapes with high spatial heterogeneity. This preliminary research evaluates the ability of remotely sensed hyperspectral data to quantify soil moisture for the Little River Experimental Watershed (LREW), Georgia. An airborne hyperspectral instrument with a short-wavelength infrared (SWIR) sensor was flown in 2005 and 2007 and the results were correlated to in situ soil moisture values. A significant statistical correlation (R 2 value above 0.7 for both sampling dates) for the hyperspectral instrument data and the soil moisture probe data at 5.08 cm (2 inches) was determined. While models for the 20.32 cm (8 inches) and 30.48 cm (12 inches) depths were tested, they were not able to estimate soil moisture to the same degree.

  15. Remote sensing of soil moisture using airborne hyperspectral data

    USGS Publications Warehouse

    Finn, M.; Lewis, M.; Bosch, D.; Giraldo, Mario; Yamamoto, K.; Sullivan, D.; Kincaid, R.; Luna, R.; Allam, G.; Kvien, Craig; Williams, M.

    2011-01-01

    Landscape assessment of soil moisture is critical to understanding the hydrological cycle at the regional scale and in broad-scale studies of biophysical processes affected by global climate changes in temperature and precipitation. Traditional efforts to measure soil moisture have been principally restricted to in situ measurements, so remote sensing techniques are often employed. Hyperspectral sensors with finer spatial resolution and narrow band widths may offer an alternative to traditional multispectral analysis of soil moisture, particularly in landscapes with high spatial heterogeneity. This preliminary research evaluates the ability of remotely sensed hyperspectral data to quantify soil moisture for the Little River Experimental Watershed (LREW), Georgia. An airborne hyperspectral instrument with a short-wavelength infrared (SWIR) sensor was flown in 2005 and 2007 and the results were correlated to in situ soil moisture values. A significant statistical correlation (R2 value above 0.7 for both sampling dates) for the hyperspectral instrument data and the soil moisture probe data at 5.08 cm (2 inches) was determined. While models for the 20.32 cm (8 inches) and 30.48 cm (12 inches) depths were tested, they were not able to estimate soil moisture to the same degree.

  16. Active microwave remote sensing of oceans, chapter 3

    NASA Technical Reports Server (NTRS)

    1975-01-01

    A rationale is developed for the use of active microwave sensing in future aerospace applications programs for the remote sensing of the world's oceans, lakes, and polar regions. Summaries pertaining to applications, local phenomena, and large-scale phenomena are given along with a discussion of orbital errors.

  17. Passive microwave remote sensing of soil moisture

    NASA Technical Reports Server (NTRS)

    Kondratyev, K. Y.; Melentyev, V. V.; Rabinovich, Y. I.; Shulgina, E. M.

    1977-01-01

    The theory and calculations of microwave emission from the medium with the depth-dependent physical properties are discussed; the possibility of determining the vertical profiles of temperature and humidity is considered. Laboratory and aircraft measurements of the soil moisture are described; the technique for determining the productive-moisture content in soil, and the results of aircraft measurements are given.

  18. Aerosol Remote Sensing Applications for Airborne Multiangle, Multispectral Shortwave Radiometers

    NASA Astrophysics Data System (ADS)

    von Bismarck, Jonas; Ruhtz, Thomas; Starace, Marco; Hollstein, André; Preusker, René; Fischer, Jürgen

    2010-05-01

    and ground based operations of the instruments so far, only two exemplary campaigns shall be introduced here. FUBEX in July 2008 was the first airborne campaign with FUBISS-ASA2, FUBISS-ZENITH and AMSSP-EM simultaneously mounted on the Cessna 207T of the Institute for Space Sciences, based in Berlin. Vertical radiation profiles recorded on July 28 in 2008 where used for a first application of the introduced inversion algorithm. In Oktober/November 2009, FUBISS-ASA2 and FUBISS-ZENITH where mounted on the German research icebreaker FS Polarstern, crossing the Atlantic on its cruise from Bremerhaven (Germany) to Punta Arenas (Chile). Measurements where performed throughout the whole cruise on days with a variety of different atmospheric conditions, as a Saharan dust outbreak over Cape Verde, typical marine conditions with salt particles in the marine boundary layer and also pristine conditions in the southern Atlantic. Access to the data of other instruments aboard the ship, as a Raman-Lidar, a cloud camera, weather station, and a microwave radiometer, provided valuable a priori information for processing and calibration of the measurements. The results may be of special interest for the validation of satellite aerosol products.

  19. Investigating Baseline, Alternative and Copula-based Algorithm for combining Airborne Active and Passive Microwave Observations in the SMAP Context

    NASA Astrophysics Data System (ADS)

    Montzka, C.; Lorenz, C.; Jagdhuber, T.; Laux, P.; Hajnsek, I.; Kunstmann, H.; Entekhabi, D.; Vereecken, H.

    2015-12-01

    The objective of the NASA Soil Moisture Active & Passive (SMAP) mission is to provide global measurements of soil moisture and freeze/thaw states. SMAP integrates L-band radar and radiometer instruments as a single observation system combining the respective strengths of active and passive remote sensing for enhanced soil moisture mapping. Airborne instruments will be a key part of the SMAP validation program. Here, we present an airborne campaign in the Rur catchment, Germany, in which the passive L-band system Polarimetric L-band Multi-beam Radiometer (PLMR2) and the active L-band system F-SAR of DLR were flown simultaneously on the same platform on six dates in 2013. The flights covered the full heterogeneity of the area under investigation, i.e. all types of land cover and experimental monitoring sites with in situ sensors. Here, we used the obtained data sets as a test-bed for the analysis of three active-passive fusion techniques: A) The SMAP baseline algorithm: Disaggregation of passive microwave brightness temperature by active microwave backscatter and subsequent inversion to soil moisture, B), the SMAP alternative algorithm: Estimation of soil moisture by passive sensor data and subsequent disaggregation by active sensor backscatter and C) Copula-based combination of active and passive microwave data. For method C empirical Copulas were generated and theoretical Copulas fitted both on the level of the raw products brightness temperature and backscatter as well as two soil moisture products. Results indicate that the regression parameters for method A and B are dependent on the radar vegetation index (RVI). Similarly, for method C the best performance was gained by generating separate Copulas for individual land use classes. For more in-depth analyses longer time series are necessary as can obtained by airborne campaigns, therefore, the methods will be applied to SMAP data.

  20. Development of an airborne remote sensing system for crop pest management: System integration and verification

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Remote sensing along with Global Positioning Systems, Geographic Information Systems, and variable rate technology has been developed, which scientists can implement to help farmers maximize the economic and environmental benefits of crop pest management through precision agriculture. Airborne remo...

  1. Optical component of the European Airborne Remote Sensing Capabilities (EARSEC)

    NASA Astrophysics Data System (ADS)

    Carrere, Veronique; Oertel, Dieter; Verdebout, Jean; Maracci, G.; Schmuck, Guido; Sieber, Alois J.

    1995-06-01

    The European Ariborne Remote Sensing Capabilities (EARSEC) is a program of the Commission of the European Union in coordination with the European Space Agency. Its goal is to establish an independent European state-of-the-art capability in remote sensing for a wide range of applications. The core instrument of the 'Optical' component of EARSEC is an Imaging Spectrometer (the Digital Airborne Imaging Spectrometer 7915 or DIAS 7915) built by Geophysical & Environmental Research Corporation (GER) and operated by DLR, Oberpfaffenhofen, in collaboration with JRC. The 79 channel high resolution Imaging Spectrometer (IS) covers the 0.4 to 12.3 micrometers wavelength range with a spectral resolution varying from 16 to 2000 nm. Operated from a Dornier 228 aircraft, the spatial resolution can vary between 3 and 15 m. The instrument is calibrated and improved at DLR and should be operational in 1995 for campaigns over Europe. The 'Optical' component of EARSEC also includes ground facilities, mainly an electro-optical (EO) processor developed for JRC by Earth Observation Sciences Limited in the United Kingdom for DAIS 7915 data processing. This processor will generate four levels of products, from simple ingestion, to calibration into physical units of radiance, to geolocation and geocoding. Collaborations are foreseen with European groups operating other advanced optical sensors such as the Italian LARA project, operating the MIVIS (IS comparable to the DAIS), and DLR, operating the ROSIS (developed for marine applications, covering the 430-850 nm region). The EO processor could be adapted in the future to handle other IS data for a more universal use.

  2. Systems and methods for remote long standoff biometric identification using microwave cardiac signals

    NASA Technical Reports Server (NTRS)

    McGrath, William R. (Inventor); Talukder, Ashit (Inventor)

    2012-01-01

    Systems and methods for remote, long standoff biometric identification using microwave cardiac signals are provided. In one embodiment, the invention relates to a method for remote biometric identification using microwave cardiac signals, the method including generating and directing first microwave energy in a direction of a person, receiving microwave energy reflected from the person, the reflected microwave energy indicative of cardiac characteristics of the person, segmenting a signal indicative of the reflected microwave energy into a waveform including a plurality of heart beats, identifying patterns in the microwave heart beats waveform, and identifying the person based on the identified patterns and a stored microwave heart beats waveform.

  3. Microwave remote sensing of sea ice

    NASA Technical Reports Server (NTRS)

    Comiso, J. C.

    1988-01-01

    The long term objectives are: (1) to understand the physics of the multispectral microwave radiative characteristics of sea ice as it goes through different phases; (2) to improve characterization of sea ice cover using satellite microwave sensors; and (3) to study ice/ocean physical and biological processes associated with polynya formations and variability of the marginal sea ice region. Two field experiments were conducted to pursue these objectives. One involved measurements of radiative and physical characteristics of sea ice from a ship during a 3-month long cruise through the Weddell Sea ice pack during the Austral winter of 1986. The other involved similar measurements from two aircrafts and a submarine over the Central Arctic and Greenland Sea region. Preliminary results have already led to an enhanced understanding of the microwave signatures of pancake ice, nilas, first year ice, multiyear ice and effects of snow cover. Coastal and deep ocean polynyas and their role in bottom water formation and ocean circulation were studied using a time series of ice images from SMMR. An unsupervised cluster analysis of Arctic sea ice using SMMR and THIR emissivity and brightness temperature data was implemented. The analysis indicates the existence of several unique and persistent clusters in the Central Arctic region during winter and that the sum of the area of these clusters excluding those of first year ice is about 20 percent less than minimum ice cover area inferred from a previous summer data. This result is consistent with saline surface for some multiyear ice floes as observed during MIZEZ and suggests that a significant fraction of multiyear ice floes in the Arctic have first year ice signatures.

  4. Applications of Microwaves to Remote Sensing of Terrain

    NASA Technical Reports Server (NTRS)

    Porter, R. A.

    1975-01-01

    A survey and study was conducted to define the role that microwaves may play in the measurement of a variety of terrain-related parameters. The survey consisted of discussions with many users and researchers in the field of remote sensing. In addition, a survey questionnaire was prepared and replies were solicited from these and other users and researchers. The results of the survey, and associated bibliography, were studied and conclusions were drawn as to the usefulness of radiometric systems for remote sensing of terrain.

  5. Remote Strain Sensing of CFRP Using Microwave Frequency Domain Reflectometry

    NASA Technical Reports Server (NTRS)

    Wilson, William C.; Moore, Jason P.; Juarez, Peter D.

    2016-01-01

    NASA's Advanced Composites Project is investigating technologies that increase automated remote inspection of aircraft composite structures. Therefore, microwave Frequency Domain Reflectometry (FDR) is being investigated as a method of enabling rapid remote measurement of strain occurring at the first ply of a composite fiber reinforced polymer (CFRP) structure using Radio Frequency (RF) Electro-Magnetic (EM) radiation. While microwave reflectometry has been used to detect disbonds in CFRP structures, its use in detecting strain has been limited. This work will present data demonstrating the measurement of the reactance changes due to loading conditions that are indicative of strain in a CFRP structure. In addition, the basic EM signature will be presented along with an analysis of temperature and humidity effects.

  6. Progress in microwave remote sensing of soil moisture

    NASA Technical Reports Server (NTRS)

    Engman, Edwin T.

    1990-01-01

    Significant progress has been made in the application of microwave remote sensing for measuring soil moisture. Both passive and active systems have demonstrated the capability for measuring soil moisture. However, several questions are still unresolved regarding the optimal instrument configuration and other target characteristics, such as roughness and vegetation. In addition, the most likely disciplines for using these data, agriculture and hydrology, do not currently possess adequate models or procedures for using these new data.

  7. Guidelines for spaceborne microwave remote sensors

    NASA Technical Reports Server (NTRS)

    Litman, V.; Nicholas, J.

    1982-01-01

    A handbook was developed to provide information and support to the spaceborne remote sensing and frequency management communities: to guide sensor developers in the choice of frequencies; to advise regulators on sensor technology needs and sharing potential; to present sharing analysis models and, through example, methods for determining sensor sharing feasibility; to introduce developers to the regulatory process; to create awareness of proper assignment procedures; to present sensor allocations; and to provide guidelines on the use and limitations of allocated bands. Controlling physical factors and user requirements and the regulatory environment are discussed. Sensor frequency allocation achievable performance and usefulness are reviewed. Procedures for national and international registration, the use of non-allocated bands and steps for obtaining new frequency allocations, and procedures for reporting interference are also discussed.

  8. Analysis of remote sensing data collected for detection and mapping of oil spills: Reduction and analysis of multi-sensor airborne data of the NASA Wallops oil spill exercise of November 1978

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Airborne, remotely sensed data of the NASA Wallops controlled oil spill were corrected, reduced and analysed. Sensor performance comparisons were made by registering data sets from different sensors, which were near-coincident in time and location. Multispectral scanner images were, in turn, overlayed with profiles of correlation between airborne and laboratory-acquired fluorosensor spectra of oil; oil-thickness contours derived (by NASA) from a scanning fluorosensor and also from a two-channel scanning microwave radiometer; and synthetic aperture radar X-HH images. Microwave scatterometer data were correlated with dual-channel (UV and TIR) line scanner images of the oil slick.

  9. AIRBORNE, OPTICAL REMOTE SENSNG OF METHANE AND ETHANE FOR NATURAL GAS PIPELINE LEAK DETECTION

    SciTech Connect

    Jerry Myers

    2005-04-15

    Ophir Corporation was awarded a contract by the U. S. Department of Energy, National Energy Technology Laboratory under the Project Title ''Airborne, Optical Remote Sensing of Methane and Ethane for Natural Gas Pipeline Leak Detection'' on October 14, 2002. The scope of the work involved designing and developing an airborne, optical remote sensor capable of sensing methane and, if possible, ethane for the detection of natural gas pipeline leaks. Flight testing using a custom dual wavelength, high power fiber amplifier was initiated in February 2005. Ophir successfully demonstrated the airborne system, showing that it was capable of discerning small amounts of methane from a simulated pipeline leak. Leak rates as low as 150 standard cubic feet per hour (scf/h) were detected by the airborne sensor.

  10. [Atmospheric Influences Analysis on the Satellite Passive Microwave Remote Sensing].

    PubMed

    Qiu, Yu-bao; Shi, Li-juan; Shi, Jian-cheng; Zhao, Shao-jie

    2016-02-01

    Passive microwave remote sensing offers its all-weather work capabilities, but atmospheric influences on satellite microwave brightness temperature were different under different atmospheric conditions and environments. In order to clarify atmospheric influences on Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E), atmospheric radiation were simulated based on AMSR-E configuration under clear sky and cloudy conditions, by using radiative transfer model and atmospheric conditions data. Results showed that atmospheric water vapor was the major factor for atmospheric radiation under clear sky condition. Atmospheric transmittances were almost above 0.98 at AMSR-E's low frequencies (< 18.7 GHz) and the microwave brightness temperature changes caused by atmosphere can be ignored in clear sky condition. Atmospheric transmittances at 36.5 and 89 GHz were 0.896 and 0.756 respectively. The effects of atmospheric water vapor needed to be corrected when using microwave high-frequency channels to inverse land surface parameters in clear sky condition. But under cloud cover or cloudy conditions, cloud liquid water was the key factor to cause atmospheric radiation. When sky was covered by typical stratus cloud, atmospheric transmittances at 10.7, 18.7 and 36.5 GHz were 0.942, 0.828 and 0.605 respectively. Comparing with the clear sky condition, the down-welling atmospheric radiation caused by cloud liquid water increased up to 75.365 K at 36.5 GHz. It showed that the atmospheric correction under different clouds covered condition was the primary work to improve the accuracy of land surface parameters inversion of passive microwave remote sensing. The results also provided the basis for microwave atmospheric correction algorithm development. Finally, the atmospheric sounding data was utilized to calculate the atmospheric transmittance of Hailaer Region, Inner Mongolia province, in July 2013. The results indicated that atmospheric transmittances were close to 1

  11. [Atmospheric Influences Analysis on the Satellite Passive Microwave Remote Sensing].

    PubMed

    Qiu, Yu-bao; Shi, Li-juan; Shi, Jian-cheng; Zhao, Shao-jie

    2016-02-01

    Passive microwave remote sensing offers its all-weather work capabilities, but atmospheric influences on satellite microwave brightness temperature were different under different atmospheric conditions and environments. In order to clarify atmospheric influences on Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E), atmospheric radiation were simulated based on AMSR-E configuration under clear sky and cloudy conditions, by using radiative transfer model and atmospheric conditions data. Results showed that atmospheric water vapor was the major factor for atmospheric radiation under clear sky condition. Atmospheric transmittances were almost above 0.98 at AMSR-E's low frequencies (< 18.7 GHz) and the microwave brightness temperature changes caused by atmosphere can be ignored in clear sky condition. Atmospheric transmittances at 36.5 and 89 GHz were 0.896 and 0.756 respectively. The effects of atmospheric water vapor needed to be corrected when using microwave high-frequency channels to inverse land surface parameters in clear sky condition. But under cloud cover or cloudy conditions, cloud liquid water was the key factor to cause atmospheric radiation. When sky was covered by typical stratus cloud, atmospheric transmittances at 10.7, 18.7 and 36.5 GHz were 0.942, 0.828 and 0.605 respectively. Comparing with the clear sky condition, the down-welling atmospheric radiation caused by cloud liquid water increased up to 75.365 K at 36.5 GHz. It showed that the atmospheric correction under different clouds covered condition was the primary work to improve the accuracy of land surface parameters inversion of passive microwave remote sensing. The results also provided the basis for microwave atmospheric correction algorithm development. Finally, the atmospheric sounding data was utilized to calculate the atmospheric transmittance of Hailaer Region, Inner Mongolia province, in July 2013. The results indicated that atmospheric transmittances were close to 1

  12. Development of a Cost-Effective Airborne Remote Sensing System for Coastal Monitoring.

    PubMed

    Kim, Duk-jin; Jung, Jungkyo; Kang, Ki-mook; Kim, Seung Hee; Xu, Zhen; Hensley, Scott; Swan, Aaron; Duersch, Michael

    2015-09-30

    Coastal lands and nearshore marine areas are productive and rapidly changing places. However, these areas face many environmental challenges related to climate change and human-induced impacts. Space-borne remote sensing systems may be restricted in monitoring these areas because of their spatial and temporal resolutions. In situ measurements are also constrained from accessing the area and obtaining wide-coverage data. In these respects, airborne remote sensing sensors could be the most appropriate tools for monitoring these coastal areas. In this study, a cost-effective airborne remote sensing system with synthetic aperture radar and thermal infrared sensors was implemented to survey coastal areas. Calibration techniques and geophysical model algorithms were developed for the airborne system to observe the topography of intertidal flats, coastal sea surface current, sea surface temperature, and submarine groundwater discharge.

  13. Development of a Cost-Effective Airborne Remote Sensing System for Coastal Monitoring

    PubMed Central

    Kim, Duk-jin; Jung, Jungkyo; Kang, Ki-mook; Kim, Seung Hee; Xu, Zhen; Hensley, Scott; Swan, Aaron; Duersch, Michael

    2015-01-01

    Coastal lands and nearshore marine areas are productive and rapidly changing places. However, these areas face many environmental challenges related to climate change and human-induced impacts. Space-borne remote sensing systems may be restricted in monitoring these areas because of their spatial and temporal resolutions. In situ measurements are also constrained from accessing the area and obtaining wide-coverage data. In these respects, airborne remote sensing sensors could be the most appropriate tools for monitoring these coastal areas. In this study, a cost-effective airborne remote sensing system with synthetic aperture radar and thermal infrared sensors was implemented to survey coastal areas. Calibration techniques and geophysical model algorithms were developed for the airborne system to observe the topography of intertidal flats, coastal sea surface current, sea surface temperature, and submarine groundwater discharge. PMID:26437413

  14. Determination of precipitation profiles from airborne passive microwave radiometric measurements

    NASA Technical Reports Server (NTRS)

    Kummerow, Christian; Hakkarinen, Ida M.; Pierce, Harold F.; Weinman, James A.

    1991-01-01

    This study presents the first quantitative retrievals of vertical profiles of precipitation derived from multispectral passive microwave radiometry. Measurements of microwave brightness temperature (Tb) obtained by a NASA high-altitude research aircraft are related to profiles of rainfall rate through a multichannel piecewise-linear statistical regression procedure. Statistics for Tb are obtained from a set of cloud radiative models representing a wide variety of convective, stratiform, and anvil structures. The retrieval scheme itself determines which cloud model best fits the observed meteorological conditions. Retrieved rainfall rate profiles are converted to equivalent radar reflectivity for comparison with observed reflectivities from a ground-based research radar. Results for two case studies, a stratiform rain situation and an intense convective thunderstorm, show that the radiometrically derived profiles capture the major features of the observed vertical structure of hydrometer density.

  15. Remote sensing of soil moisture with microwave radiometers

    NASA Technical Reports Server (NTRS)

    Schmugge, T.; Wilheit, T.; Webster, W., Jr.; Gloerson, P.

    1976-01-01

    Results are presented that were derived from measurements made by microwave radiometers during the March 1972 and February 1973 flights of National Aeronautics and Space Administration (NASA) Convair-9900 aircraft over agricultural test sites in the southwestern part of United States. The purpose of the missions was to study the use of microwave radiometers for the remote sensing of soil moisture. The microwave radiometers covered the 0.8- to 21-cm wavelength range. The results show a good linear correlation between the observed microwave brightness temperature and moisture content of the 0- to 1-cm layer of the soil. The results at the largest wavelength (21 cm) show the greatest sensitivity to soil moisture variations and indicate the possibility of sensing these variations through a vegetative canopy. The effect of soil texture on the emission from the soil was also studied and it was found that this effect can be compensated for by expressing soil moisture as a percent of field capacity for the soil. The results were compared with calculations based on a radiative transfer model for layered dielectrics and the agreement is very good at the longer wavelengths. At the shorter wavelengths, surface roughness effects are larger and the agreement becomes poorer.

  16. Microwave remote sensing measurements of oil pollution on the ocean

    NASA Technical Reports Server (NTRS)

    Croswell, W. F.; Blume, H.-J. C.; Johnson, J. W.

    1981-01-01

    Microwave and optical remote sensors were flown over fresh and weathered crude oil released from a surface research vessel and also over a slick formed on the sea by frozen oleyl alcohol cubes released from a helicopter. For the crude oil experiments, microwave radiometric measurements at 1.43, 2.65, 22, and 31 GHz are reported, along with the variable incidence angle scattering measurements at 13.9 GHz. For these experiments, unusual depressions in the L-band brightness temperature were observed, possibly related to dispersants applied to the crude oil. Similar depressions, but with much larger values, were observed over the oleyl alcohol monomolecular slicks. Images obtained at 31 and 22 GHz were used to infer oil volume, yielding values which bound the known amounts spilled. Ku band measurements obtained in repeated passes over crude oil slicks are also discussed.

  17. Passive microwave remote sensing for sea ice research

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Techniques for gathering data by remote sensors on satellites utilized for sea ice research are summarized. Measurement of brightness temperatures by a passive microwave imager converted to maps of total sea ice concentration and to the areal fractions covered by first year and multiyear ice are described. Several ancillary observations, especially by means of automatic data buoys and submarines equipped with upward looking sonars, are needed to improve the validation and interpretation of satellite data. The design and performance characteristics of the Navy's Special Sensor Microwave Imager, expected to be in orbit in late 1985, are described. It is recommended that data from that instrument be processed to a form suitable for research applications and archived in a readily accessible form. The sea ice data products required for research purposes are described and recommendations for their archival and distribution to the scientific community are presented.

  18. Analysis of interference to remote passive microwave sensors

    NASA Technical Reports Server (NTRS)

    Boyd, Douglas; Tillotson, Tom

    1986-01-01

    The final acts of the 1979 World Administrative Radio Conference (WARC) were analyzed to determine potential interference to remote passive microwave sensors. Using interferer populations determined from the U.S. Government and FCC Master File Lists and assuming uniform geographical distribution of interferers, the level of interference from shared services and active services in adjacent and subharmonic bands was calculated for each of the 22 passive sensing bands. In addition, due to the theoretically large antennas required for passive sensing, an analysis was performed to determine if smaller antennas, i.e., relaxed resolution requirements, would have an effect on interference and to what extent.

  19. Active microwave remote sensing of earth/land, chapter 2

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Geoscience applications of active microwave remote sensing systems are examined. Major application areas for the system include: (1) exploration of petroleum, mineral, and ground water resources, (2) mapping surface and structural features, (3) terrain analysis, both morphometric and genetic, (4) application in civil works, and (5) application in the areas of earthquake prediction and crustal movements. Although the success of radar surveys has not been widely publicized, they have been used as a prime reconnaissance data base for mineral exploration and land-use evaluation in areas where photography cannot be obtained.

  20. A microwave pressure sounder. [for remote measurement of atmospheric pressure

    NASA Technical Reports Server (NTRS)

    Peckham, G. E.; Flower, D. A.

    1981-01-01

    A technique for the remote measurement of atmospheric surface pressure will be described. Such measurements could be made from a satellite in polar orbit and would cover many areas for which conventional meteorological data are not available. An active microwave instrument is used to measure the strength of return echoes from the ocean surface at a number of frequencies near the 60 GHz oxygen absorption band. Factors which affect the accuracy with which surface pressure can be deduced from these measurements will be discussed and an instrument designed to test the method by making measurements from an aircraft will be described.

  1. Airborne Remote Sensing of River Flow and Morphology

    NASA Astrophysics Data System (ADS)

    Zuckerman, S.; Anderson, S. P.; McLean, J.; Redford, R.

    2014-12-01

    River morphology, surface slope and flow are some of the fundamental measurements required for surface water monitoring and hydrodynamic research. This paper describes a method of combining bathymetric lidar with space-time processing of mid-wave infrared (MWIR) imagery to simultaneously measure bathymetry, currents and surface slope from an airborne platform. In May 2014, Areté installed a Pushbroom Imaging Lidar for Littoral Surveillance (PILLS) and a FLIR SC8000 MWIR imaging system sampling at 2 Hz in a small twin-engine aircraft. Data was collected over the lower Colorado River between Picacho Park and Parker. PILLS is a compact bathymetric lidar based on streak-tube sensor technology. It provides channel and bank topography and water surface elevation at 1 meter horizontal scales and 25 cm vertical accuracy. Surface currents are derived from the MWIR imagery by tracking surface features using a cross correlation algorithm. This approach enables the retrieval of currents along extended reaches at the forward speed of the aircraft with spatial resolutions down to 5 m with accuracy better than 10 cm/s. The fused airborne data captures current and depth variability on scales of meters over 10's of kilometers collected in just a few minutes. The airborne MWIR current retrievals are combined with the bathymetric lidar data to calculate river discharge which is then compared with real-time streamflow stations. The results highlight the potential for improving our understanding of complex river environments with simultaneous collections from multiple airborne sensors.

  2. Airborne Dial Remote Sensing of the Arctic Ozone Layer

    NASA Technical Reports Server (NTRS)

    Wirth, Martin; Renger, Wolfgang; Ehret, Gerhard

    1992-01-01

    A combined ozone and aerosol LIDAR was developed at the Institute of Physics of the Atmosphere at the DLR in Oberpfaffenhofen. It is an airborne version, that, based on the DIAL-principle, permits the recording of two-dimensional ozone profiles. This presentation will focus on the ozone-part; the aerosol subsection will be treated later.

  3. Remote sensing of soil moisture using airborne hyperspectral data

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Institute for Technology Development (ITD) has developed an airborne hyperspectral sensor system that collects electromagnetic reflectance data of the terrain. The system consists of sensors for three different sections of the electromagnetic spectrum; the Ultra-Violet (UV), Visible/Near Infrare...

  4. Real-time remote detection and measurement for airborne imaging spectroscopy: a case study with methane

    NASA Astrophysics Data System (ADS)

    Thompson, D. R.; Leifer, I.; Bovensmann, H.; Eastwood, M.; Fladeland, M.; Frankenberg, C.; Gerilowski, K.; Green, R. O.; Kratwurst, S.; Krings, T.; Luna, B.; Thorpe, A. K.

    2015-06-01

    Localized anthropogenic sources of atmospheric CH4 are highly uncertain and temporally variable. Airborne remote measurement is an effective method to detect and quantify these emissions. In a campaign context, the science yield can be dramatically increased by real-time retrievals that allow operators to coordinate multiple measurements of the most active areas. This can improve science outcomes for both single- and multiple-platform missions. We describe a case study of the NASA/ESA CO2 and Methane Experiment (COMEX) campaign in California during June and August/September 2014. COMEX was a multi-platform campaign to measure CH4 plumes released from anthropogenic sources including oil and gas infrastructure. We discuss principles for real-time spectral signature detection and measurement, and report performance on the NASA Next Generation Airborne Visible Infrared Spectrometer (AVIRIS-NG). AVIRIS-NG successfully detected CH4 plumes in real-time at Gb s-1 data rates, characterizing fugitive releases in concert with other in situ and remote instruments. The teams used these real-time CH4 detections to coordinate measurements across multiple platforms, including airborne in situ, airborne non-imaging remote sensing, and ground-based in situ instruments. To our knowledge this is the first reported use of real-time trace gas signature detection in an airborne science campaign, and presages many future applications.

  5. Remote sensing for non-renewable resources - Satellite and airborne multiband scanners for mineral exploration

    NASA Technical Reports Server (NTRS)

    Goetz, Alexander F. H.

    1986-01-01

    The application of remote sensing techniques to mineral exploration involves the use of both spatial (morphological) as well as spectral information. This paper is directed toward a discussion of the uses of spectral image information and emphasizes the newest airborne and spaceborne sensor developments involving imaging spectrometers.

  6. Daily evapotranspiration estimates from extrapolating instantaneous airborne remote sensing ET values

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study, six extrapolation methods have been compared for their ability to estimate daily crop evapotranspiration (ETd) from instantaneous latent heat flux estimates derived from digital airborne multispectral remote sensing imagery. Data used in this study were collected during an experiment...

  7. An airborne multispectral imaging system based on two consumer-grade cameras for agricultural remote sensing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper describes the design and evaluation of an airborne multispectral imaging system based on two identical consumer-grade cameras for agricultural remote sensing. The cameras are equipped with a full-frame complementary metal oxide semiconductor (CMOS) sensor with 5616 × 3744 pixels. One came...

  8. Airborne hyperspectral systems for solving remote sensing problems

    NASA Astrophysics Data System (ADS)

    Rodionov, I. D.; Rodionov, A. I.; Vedeshin, L. A.; Vinogradov, A. N.; Egorov, V. V.; Kalinin, A. P.

    2014-12-01

    A retrospective of airborne hyperspectrometer projects carried out in the ZAO Reagent Scientific Technical Center is presented. Hyperspectral devices developed during the period since the end of 1990s to the present day are described. The line of hyperspectrometers designed in recent times covers the ranges from ultraviolet (0.2 μm) to near infrared (1.0 μm). These devices can be mounted on airborne and automobile carriers, including small-size ones. By now, the developments of hyperspectral devices in ZAO Reagent have reached the finished state and have been prepared for serial production. Their technical characteristics permit one to speak of the creation of wide-range high-aperture ultraspectral high spatial resolution equipment with a possibility of real-time data processing on board.

  9. Progress in the development of airborne remote sensing instrumentation for the National Ecological Observatory Network

    NASA Astrophysics Data System (ADS)

    Kampe, Thomas U.; McCorkel, Joel; Hamlin, Louise; Green, Robert O.; Krause, Keith S.; Johnson, Brian R.

    2011-09-01

    The National Ecological Observatory Network (NEON) is a planned facility of the National Science Foundation with the mission to enable understanding and forecasting of the impacts of climate change, land use change and invasive species on continental-scale ecology. Airborne remote sensing plays a critical role by providing measurements at the scale of individual shrubs and larger plants over hundreds of square kilometers. The NEON Airborne Observation Platform is designed to bridge scales from organism and stand scales, as captured by plot and tower observations, to the scale of satellite based remote sensing. Fused airborne spectroscopy and waveform LiDAR is used to quantify vegetation composition and structure. Panchromatic photography at better than 30 cm resolution will retrieve fine-scale information on land use, roads, impervious surfaces, and built structures. NEON will build three airborne systems to allow for regular coverage of NEON sites and the capacity to respond to investigator requests for specific projects. The system design achieves a balance between performance and development cost and risk, taking full advantage of existing commercial airborne LiDAR and camera components. To reduce risk during NEON construction, an imaging spectrometer design verification unit is being developed at the Jet Propulsion Laboratory to demonstrate that operational and performance requirements can be met. As part of this effort, NEON is also focusing on science algorithm development, computing hardware prototyping and early airborne test flights with similar technologies. This paper presents an overview of the development status of the NEON airborne instrumentation in the context of the NEON mission.

  10. Airborne antenna coverage requirements for the TCV B-737 aircraft. [for operation with microwave landing systems

    NASA Technical Reports Server (NTRS)

    Southall, W. A., Jr.; White, W. F.

    1978-01-01

    The airborne antenna line of sight look angle requirement for operation with a Microwave Landing System (MLS) was studied. The required azimuth and elevation line of sight look angles from an antenna located on an aircraft to three ground based antenna sites at the Wallops Flight Center (FPS-16 radar, MLS aximuth, and MLS elevation) as the aircraft follows specific approach paths selected as representative of MLS operations at the Denver, Colorado, terminal area are presented. These required azimuth and elevation look angles may be interpreted as basic design requirements for antenna of the TCV B-737 airplane for MLS operations along these selected approach paths.

  11. The Australian National Airborne Field Experiment 2005: Soil Moisture Remote Sensing at 60 Meter Resolution and Up

    NASA Technical Reports Server (NTRS)

    Kim, E. J.; Walker, J. P.; Panciera, R.; Kalma, J. D.

    2006-01-01

    Spatially-distributed soil moisture observations have applications spanning a wide range of spatial resolutions from the very local needs of individual farmers to the progressively larger areas of interest to weather forecasters, water resource managers, and global climate modelers. To date, the most promising approach for space-based remote sensing of soil moisture makes use of passive microwave emission radiometers at L-band frequencies (1-2 GHz). Several soil moisture-sensing satellites have been proposed in recent years, with the European Space Agency's Soil Moisture Ocean Salinity (SMOS) mission scheduled to be launched first in a couple years. While such a microwave-based approach has the advantage of essentially allweather operation, satellite size limits spatial resolution to 10's of km. Whether used at this native resolution or in conjunction with some type of downscaling technique to generate soil moisture estimates on a finer-scale grid, the effects of subpixel spatial variability play a critical role. The soil moisture variability is typically affected by factors such as vegetation, topography, surface roughness, and soil texture. Understanding and these factors is the key to achieving accurate soil moisture retrievals at any scale. Indeed, the ability to compensate for these factors ultimately limits the achievable spatial resolution and/or accuracy of the retrieval. Over the last 20 years, a series of airborne campaigns in the USA have supported the development of algorithms for spaceborne soil moisture retrieval. The most important observations involved imagery from passive microwave radiometers. The early campaigns proved that the retrieval worked for larger and larger footprints, up to satellite-scale footprints. These provided the solid basis for proposing the satellite missions. More recent campaigns have explored other aspects such as retrieval performance through greater amounts of vegetation. All of these campaigns featured extensive ground

  12. Microwave remote sensing of a two-layer random medium

    NASA Technical Reports Server (NTRS)

    Tsang, L.; Kong, J. A.

    1976-01-01

    A two-variable expansion technique is used to solve for the mean Green's. function from the Dyson equation under the nonlinear approximation. The Bethe-Salpeter equation then gives rise to a set of modified radiative transfer (MRT) equations which accommodate coherent effects essential to bounded media. It is found that the nonlinear approximation, instead of the more popular bilocal approximation, should be used for the case of bounded media. The two approximations yield identical results for unbounded media. The MRT equations are then solved for a two-layer random medium. The MRT equations give rise to simple and useful solutions which are applicable to both active and passive microwave remote sensing.

  13. Estimating Crop Residue Distribution Using Airborne and Satellite Remote Sensing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Crop residue management and reduced tillage are commonly accepted best management practices that improve soil quality through the sequestration of soil organic carbon. A major goal of this study was to evaluate remote sensing data for rapid quantification of conservation tillage at the field and wa...

  14. Airborne remote sensing to detect greenbug stress to wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vegetation indices calculated from the quantity of reflected electromagnetic radiation have been used to quantify levels of stress to plants. Greenbugs cause stress to wheat plants and therefore multi-spectral remote sensing may be useful for detecting greenbug infested wheat fields. The objective...

  15. Microwave Remote Sensing Modeling of Ocean Surface Salinity and Winds Using an Empirical Sea Surface Spectrum

    NASA Technical Reports Server (NTRS)

    Yueh, Simon H.

    2004-01-01

    Active and passive microwave remote sensing techniques have been investigated for the remote sensing of ocean surface wind and salinity. We revised an ocean surface spectrum using the CMOD-5 geophysical model function (GMF) for the European Remote Sensing (ERS) C-band scatterometer and the Ku-band GMF for the NASA SeaWinds scatterometer. The predictions of microwave brightness temperatures from this model agree well with satellite, aircraft and tower-based microwave radiometer data. This suggests that the impact of surface roughness on microwave brightness temperatures and radar scattering coefficients of sea surfaces can be consistently characterized by a roughness spectrum, providing physical basis for using combined active and passive remote sensing techniques for ocean surface wind and salinity remote sensing.

  16. Microwave remote sensing in atmospheric research and meteorology (invited)

    NASA Astrophysics Data System (ADS)

    Kunzi, K.

    Remote sensing techniques to investigate the atmosphere are widely used. Sensors operating in the microwave range (wavelength from 10 to 0.1 cm) of the electromagnetic spectrum were among the first instruments used on the ground and on air- and space borne platforms for this purpose. These instruments measure the thermal emission from molecular resonances or use the absorption and scattering properties of water droplets or particles to obtain information on atmospheric parameters and composition. In the seventies the sensors NEMS and SCAMS on the Nimbus-5 and 6 satellites have demonstrated the big advantage of these instruments to obtain temperature profiles, amounts of water vapor and liquid water nearly unaffected by cloud coverage. The frequency bands and observing geometries selected for these early instruments are still used to day very successfully for the operational sensors on the polar orbiting satellites of the DMSP and NOAA series. In the eighties and nineties the very much improved sensor technology allowed to extend the spectral range to wavelength near 0.01 cm. It is now possible to observe key constituents of importance in atmospheric chemistry, and in particular related to stratospheric ozone. Such sensors have been flown on UARS (MLS), several space shuttle missions (MAS) and on stratospheric balloons using limb sounding geometry, and also on research aircraft (NASA DC-9, the DLR Falcon and others), furthermore microwave radiometers are considered key sensors for the ground based, global Network for the Detection of Stratospheric Change (NDSC). The next generation of sensors on future satellites such as AURA (MLS) and the international space station (SMILES) are making use of higher frequencies and superconducting receiver technology. This will allow to measure more minor constituents with higher accuracy and better temporal resolution. Today the receiver technology is very mature down to wavelength of 0.03 cm. Planned future applications include a

  17. Airborne Remote Sensing (ARS) for Agricultural Research and Commercialization Applications

    NASA Technical Reports Server (NTRS)

    Narayanan, Ram; Bowen, Brent D.; Nickerson, Jocelyn S.

    2002-01-01

    Tremendous advances in remote sensing technology and computing power over the last few decades are now providing scientists with the opportunity to investigate, measure, and model environmental patterns and processes with increasing confidence. Such advances are being pursued by the Nebraska Remote Sensing Facility, which consists of approximately 30 faculty members and is very competitive with other institutions in the depth of the work that is accomplished. The development of this facility targeted at applications, commercialization, and education programs in the area of precision agriculture provides a unique opportunity. This critical area is within the scope of NASA goals and objectives of NASA s Applications, Technology Transfer, Commercialization, and Education Division and the Earth Science Enterprise. This innovative integration of Aerospace (Aeronautics) Technology Enterprise applications with other NASA enterprises serves as a model of cross-enterprise transfer of science with specific commercial applications.

  18. Airborne remote sensing for geology and the environment; present and future

    USGS Publications Warehouse

    Watson, Ken; Knepper, Daniel H.

    1994-01-01

    In 1988, a group of leading experts from government, academia, and industry attended a workshop on airborne remote sensing sponsored by the U.S. Geological Survey (USGS) and hosted by the Branch of Geophysics. The purpose of the workshop was to examine the scientific rationale for airborne remote sensing in support of government earth science in the next decade. This report has arranged the six resulting working-group reports under two main headings: (1) Geologic Remote Sensing, for the reports on geologic mapping, mineral resources, and fossil fuels and geothermal resources; and (2) Environmental Remote Sensing, for the reports on environmental geology, geologic hazards, and water resources. The intent of the workshop was to provide an evaluation of demonstrated capabilities, their direct extensions, and possible future applications, and this was the organizational format used for the geologic remote sensing reports. The working groups in environmental remote sensing chose to present their reports in a somewhat modified version of this format. A final section examines future advances and limitations in the field. There is a large, complex, and often bewildering array of remote sensing data available. Early remote sensing studies were based on data collected from airborne platforms. Much of that technology was later extended to satellites. The original 80-m-resolution Landsat Multispectral Scanner System (MSS) has now been largely superseded by the 30-m-resolution Thematic Mapper (TM) system that has additional spectral channels. The French satellite SPOT provides higher spatial resolution for channels equivalent to MSS. Low-resolution (1 km) data are available from the National Oceanographic and Atmospheric Administration's AVHRR system, which acquires reflectance and day and night thermal data daily. Several experimental satellites have acquired limited data, and there are extensive plans for future satellites including those of Japan (JERS), Europe (ESA), Canada

  19. Real-time remote detection and measurement for airborne imaging spectroscopy: a case study with methane

    NASA Astrophysics Data System (ADS)

    Thompson, D. R.; Leifer, I.; Bovensmann, H.; Eastwood, M.; Fladeland, M.; Frankenberg, C.; Gerilowski, K.; Green, R. O.; Kratwurst, S.; Krings, T.; Luna, B.; Thorpe, A. K.

    2015-10-01

    Localized anthropogenic sources of atmospheric CH4 are highly uncertain and temporally variable. Airborne remote measurement is an effective method to detect and quantify these emissions. In a campaign context, the science yield can be dramatically increased by real-time retrievals that allow operators to coordinate multiple measurements of the most active areas. This can improve science outcomes for both single- and multiple-platform missions. We describe a case study of the NASA/ESA CO2 and MEthane eXperiment (COMEX) campaign in California during June and August/September 2014. COMEX was a multi-platform campaign to measure CH4 plumes released from anthropogenic sources including oil and gas infrastructure. We discuss principles for real-time spectral signature detection and measurement, and report performance on the NASA Next Generation Airborne Visible Infrared Spectrometer (AVIRIS-NG). AVIRIS-NG successfully detected CH4 plumes in real-time at Gb s-1 data rates, characterizing fugitive releases in concert with other in situ and remote instruments. The teams used these real-time CH4 detections to coordinate measurements across multiple platforms, including airborne in situ, airborne non-imaging remote sensing, and ground-based in situ instruments. To our knowledge this is the first reported use of real-time trace-gas signature detection in an airborne science campaign, and presages many future applications. Post-analysis demonstrates matched filter methods providing noise-equivalent (1σ) detection sensitivity for 1.0 % CH4 column enhancements equal to 141 ppm m.

  20. Potential Application of Airborne Passive Microwave Observations for Monitoring Inland Flooding Caused by Tropical Cyclones

    NASA Technical Reports Server (NTRS)

    Hood, Robbie E.; Radley, C.D.; LaFontaine, F.J.

    2008-01-01

    Inland flooding from tropical cyclones can be a significant factor in storm-related deaths in the United States and other countries. Information collected during NASA tropical cyclone field studies suggest surface water and flooding induced by tropical cyclone precipitation can be detected and therefore monitored using passive microwave airborne radiometers. In particular, the 10.7 GHz frequency of the NASA Advanced Microwave Precipitation Radiometer (AMPR) flown on the NASA ER-2 has demonstrated high resolution detection of anomalous surface water and flooding in numerous situations. This presentation will highlight the analysis of three cases utilizing primarily satellite and airborne radiometer data. Radiometer data from the 1998 Third Convection and Moisture Experiment (CAMEX-3) are utilized to detect surface water during landfalling Hurricane Georges in both the Dominican Republic and Louisiana. A third case is landfalling Tropical Storm Gert in Eastern Mexico during the Tropical Cloud Systems and Processes (TCSP) experiment in 2005. AMPR data are compared to topographic data and vegetation indices to evaluate the significance of the surface water signature visible in the 10.7 GHz information. The results of this study suggest the benefit of an aircraft 10 GHz radiometer to provide real-time observations of surface water conditions as part of a multi-sensor flood monitoring network.

  1. Changing scale: from site thorough landscape to taskscape within airborne remote sensing perspective

    NASA Astrophysics Data System (ADS)

    Kostyrko, Mikołaj; RÄ czkowski, Włodzimierz; Ruciński, Dominik

    2016-08-01

    In consequence of a long tradition, archaeologists focus on individual sites and features and not landscape itself. We propose to perceive the landscape as a taskscapes, a space where tasks are performed, by that its own identity is created. Airborne remote sensing methods establish a possibility of studies on a larger scale of and to perceive places as context for landscapes and vice versa. On the other hand we would like to draw attention to identification of paleoenvironment features in the context of past landscapes. Although it is not always possible to determine the relationship between these element and traces of past human activities, we must be aware that in the past they had and influence on human behavior. In this paper will address the question: how much do airborne remote sensing data through the ability to change the scale of our perspective upon archaeological sites and their local landscapes alter or enrich interpretation of the context of past human activities.

  2. Airborne test flight of HY-2A satellite microwave scatterometer and data analysis

    NASA Astrophysics Data System (ADS)

    Zou, Juhong; Guo, Maohua; Cui, Songxue; Zhou, Wu

    2016-04-01

    This paper introduces the background, aim, experimental design, configuration and data processing for an airborne test flight of the HY-2 Microwave scatterometer (HSCAT). The aim was to evaluate HSCAT performance and a developed data processing algorithm for the HSCAT before launch. There were three test flights of the scatterometer, on January 15, 18 and 22, 2010, over the South China Sea near Lingshui, Hainan. The test flights successfully generated simultaneous airborne scatterometer normalized radar cross section (NRCS), ASCAT wind, and ship-borne-measured wind datasets, which were used to analyze HSCAT performance. Azimuthal dependence of the NRCS relative to the wind direction was nearly cos(2w), with NRCS minima at crosswind directions, and maxima near upwind and downwind. The NRCS also showed a small diff erence between upwind and downwind directions, with upwind crosssections generally larger than those downwind. The dependence of airborne scatterometer NRCS on wind direction and speed showed favorable consistency with the NASA scatterometer geophysical model function (NSCAT GMF), indicating satisfactory HSCAT performance.

  3. Airborne remote sensors applied to engineering geology and civil works design investigations

    NASA Technical Reports Server (NTRS)

    Gelnett, R. H.

    1975-01-01

    The usefulness of various airborne remote sensing systems in the detection and identification of regional and specific geologic structural features that may affect the design and location of engineering structures on major civil works projects is evaluated. The Butler Valley Dam and Blue Lake Project in northern California was selected as a demonstration site. Findings derived from the interpretation of various kinds of imagery used are given.

  4. A New Airborne Lidar for Remote Sensing of Canopy Fluorescence and Vertical Profile

    NASA Astrophysics Data System (ADS)

    Ounis, A.; Bach, J.; Mahjoub, A.; Daumard, F.; Moya, I.; Goulas, Y.

    2016-06-01

    We report the development of a new lidar system for airborne remote sensing of chlorophyll fluorescence (ChlF) and vertical profile of canopies. By combining laserinduced fluorescence (LIF), sun-induced fluorescence (SIF) and canopy height distribution, the new instrument will low the simultaneous assessment of gross primary production (GPP), photosynthesis efficiency and above ground carbon stocks. Technical issues of the lidar development are discussed and expected performances are presented.

  5. Flight Tests of the DELICAT Airborne LIDAR System for Remote Clear Air Turbulence Detection

    NASA Astrophysics Data System (ADS)

    Vrancken, Patrick; Wirth, Martin; Ehret, Gerhard; Witschas, Benjamin; Veerman, Henk; Tump, Robert; Barny, Hervé; Rondeau, Philippe; Dolfi-Bouteyre, Agnès; Lombard, Laurent

    2016-06-01

    An important aeronautics application of lidar is the airborne remote detection of Clear Air Turbulence which cannot be performed with onboard radar. We report on a DLR-developed lidar system for the remote detection of such turbulent areas in the flight path of an aircraft. The lidar, consisting of a high-power UV laser transmitter and a direct detection system, was installed on a Dutch research aircraft. Flight tests executed in 2013 demonstrated the performance of the lidar system to detect local subtle variations in the molecular backscatter coefficient indicating the turbulence some 10 to 15 km ahead.

  6. Earth Science Microwave Remote Sensing at NASA's Goddard Space Flight Center

    NASA Technical Reports Server (NTRS)

    Kim, Edward; Busalacchi, Antonio J. (Technical Monitor)

    2000-01-01

    The Goddard Space Flight Center (GSFC) was established as NASA's first space flight center in 1959. Its 12,000 personnel are active in the Earth and space sciences, astronomy, space physics, tracking and communications. GSFC's mission is to expand our knowledge of the Earth and its environment, the solar system, and the universe through observations from space. The main Goddard campus is located in Greenbelt, Maryland, USA, just north of Washington, D.C. The Wallops Flight Facility (operational since 1945), located on the Atlantic coast of Virginia was consolidated with the Goddard Space Flight Center in 1982. Wallops is now NASA's principal facility for management and implementation of suborbital research programs, and supports a wide variety of airborne science missions as well. As the lead Center for NASA's Earth Science Enterprise (ESE)--a long-term, coordinated research effort to study the Earth as a global environmental system--GSFC scientists and engineers are involved in a wide range of Earth Science remote sensing activities. Their activities range from basic geoscience research to the development of instruments and technology for space missions, as well as the associated Calibration/Validation (Cal/Val) work. The shear breadth of work in these areas precludes an exhaustive description here. Rather, this article presents selected brief overviews of microwave-related Earth Science applications and the ground-based, airborne, and space instruments that are in service, under development, or otherwise significantly involving GSFC. Likewise, contributing authors are acknowledged for each section, but the results and projects they describe represent the cumulative efforts of many persons at GSFC as well as at collaborating institutions. For further information, readers are encouraged to consult the listed websites and references.

  7. AIRBORNE, OPTICAL REMOTE SENSING OF METHANE AND ETHANE FOR NATURAL GAS PIPELINE LEAK DETECTION

    SciTech Connect

    Jerry Myers

    2003-11-12

    Ophir Corporation was awarded a contract by the U. S. Department of Energy, National Energy Technology Laboratory under the Project Title ''Airborne, Optical Remote Sensing of Methane and Ethane for Natural Gas Pipeline Leak Detection'' on October 14, 2002. This second six-month technical report summarizes the progress made towards defining, designing, and developing the hardware and software segments of the airborne, optical remote methane and ethane sensor. The most challenging task to date has been to identify a vendor capable of designing and developing a light source with the appropriate output wavelength and power. This report will document the work that has been done to identify design requirements, and potential vendors for the light source. Significant progress has also been made in characterizing the amount of light return available from a remote target at various distances from the light source. A great deal of time has been spent conducting laboratory and long-optical path target reflectance measurements. This is important since it helps to establish the overall optical output requirements for the sensor. It also reduces the relative uncertainty and risk associated with developing a custom light source. The data gathered from the optical path testing has been translated to the airborne transceiver design in such areas as: fiber coupling, optical detector selection, gas filters, and software analysis. Ophir will next, summarize the design progress of the transceiver hardware and software development. Finally, Ophir will discuss remaining project issues that may impact the success of the project.

  8. Remote sensor response study in the regime of the microwave radiation-induced magnetoresistance oscillations

    SciTech Connect

    Ye, Tianyu; Mani, R. G.; Wegscheider, W.

    2013-11-04

    A concurrent remote sensing and magneto-transport study of the microwave excited two dimensional electron system (2DES) at liquid helium temperatures has been carried out using a carbon detector to remotely sense the microwave activity of the 2D electron system in the GaAs/AlGaAs heterostructure during conventional magneto-transport measurements. Various correlations are observed and reported between the oscillatory magnetotransport and the remotely sensed reflection. In addition, the oscillatory remotely sensed signal is shown to exhibit a power law type variation in its amplitude, similar to the radiation-induced magnetoresistance oscillations.

  9. Surface temperature and soil moisture retrieval in the Sahel from airborne multifrequency microwave radiometry

    SciTech Connect

    Calvet, J.C.

    1996-03-01

    Bipolarized microwave brightness temperatures of Sahel semiarid landscapes are analyzed at two frequencies: 5.05 and 36.5 GHz. These measurements were performed in Niger, West Africa, by the radiometer PORTOS in the framework of the Hydrologic Atmospheric Pilot Experiment in the Sahel (HAPEX-Sahel), during the end of the rainy season (August--September 1992). The airborne microwave data were collected simultaneously with radiosoundings of the atmosphere, and ground measurements of surface temperature, soil moisture, and biomass of several vegetation types. After estimating the soil roughness parameters, it is shown that two kinds of vegetation canopies must be considered: sparse canopies and patchy canopies including bare soil strips. The mixed soil vegetation microwave emission is analyzed using a random continuous approach. The sparse canopy emission is efficiently described by considering the vegetation layer as homogeneous. Conversely, a simple soil-vegetation mixing equation must be used for the patchy canopies. The problem with retrieving the canopy temperature and the near-surface soil moisture is addressed. For every canopy, soil moisture retrieval is possible. Soil moisture maps are proposed. The canopy temperature can also be retrieved with good accuracy provided both vertical (v) and horizontal (h) polarizations are available. It is shown that the retrieved variables can be used to separate landscape units through a classification procedure.

  10. Microwave Remote Sensing of Soil Moisture for Estimation of Soil Properties

    NASA Technical Reports Server (NTRS)

    Mattikalli, Nandish M.; Engman, Edwin T.; Jackson, Thomas J.

    1997-01-01

    Surface soil moisture dynamics was derived using microwave remote sensing, and employed to estimate soil physical and hydraulic properties. The L-band ESTAR radiometer was employed in an airborne campaign over the Little Washita watershed, Oklahoma during June 10-18, 1992. Brightness temperature (TB) data were employed in a soil moisture inversion algorithm which corrected for vegetation and soil effects. Analyses of spatial TB and soil moisture dynamics during the dry-down period revealed a direct relationship between changes in TB, soil moisture and soil texture. Extensive regression analyses were carried out which yielded statistically significant quantitative relationships between ratio of percent sand to percent clay (RSC, a term derived to quantify soil texture) and saturated hydraulic conductivity (Ksat) in terms of change components of TB and surface soil moisture. Validation of results indicated that both RSC and Ksat can be estimated with reasonable accuracy. These findings have potential applications for deriving spatial distributions of RSC and Ksat over large areas.

  11. Application of Terrestrial Microwave Remote Sensing to Agricultural Drought Monitoring

    NASA Astrophysics Data System (ADS)

    Crow, W. T.; Bolten, J. D.

    2014-12-01

    Root-zone soil moisture information is a valuable diagnostic for detecting the onset and severity of agricultural drought. Current attempts to globally monitor root-zone soil moisture are generally based on the application of soil water balance models driven by observed meteorological variables. Such systems, however, are prone to random error associated with: incorrect process model physics, poor parameter choices and noisy meteorological inputs. The presentation will describe attempts to remediate these sources of error via the assimilation of remotely-sensed surface soil moisture retrievals from satellite-based passive microwave sensors into a global soil water balance model. Results demonstrate the ability of satellite-based soil moisture retrieval products to significantly improve the global characterization of root-zone soil moisture - particularly in data-poor regions lacking adequate ground-based rain gage instrumentation. This success has lead to an on-going effort to implement an operational land data assimilation system at the United States Department of Agriculture's Foreign Agricultural Service (USDA FAS) to globally monitor variations in root-zone soil moisture availability via the integration of satellite-based precipitation and soil moisture information. Prospects for improving the performance of the USDA FAS system via the simultaneous assimilation of both passive and active-based soil moisture retrievals derived from the upcoming NASA Soil Moisture Active/Passive mission will also be discussed.

  12. A new method to inverse soil moisture based on thermal infrared and passive microwave remote sensing

    NASA Astrophysics Data System (ADS)

    Zhou, Zhuang; Kou, Xiaokang; Zhao, Shaojie; Jiang, Lingmei

    2014-11-01

    Soil moisture is one of the main factors in the water, energy and carbon cycles. It constitutes a major uncertainty in climate and hydrological models. By now, passive microwave remote sensing and thermal infrared remote sensing technology have been used to obtain and monitor soil moisture. However, as the resolution of passive microwave remote sensing is very low and the thermal infrared remote sensing method fails to provide soil temperature on cloudy days, it is hard to monitor the soil moisture accurately. To solve the problem, a new method has been tried in this research. Thermal infrared remote sensing and passive microwave remote sensing technology have been combined based on the delicate experiment. Since the soil moisture retrieved by passive microwave in general represents surface centimeters deep, which is different from deeper soil moisture estimated by thermal inertia method, a relationship between the two depths soil moisture has been established based on the experiment. The results show that there is a good relationship between the soil moisture estimated by passive microwave and thermal infrared remote sensing method. The correlation coefficient is 0.78 and RMSE (root mean square error) is 0.0195 · ?. This research provides a new possible method to inverse soil moisture.

  13. Separating vegetation and soil temperature using airborne multiangular remote sensing image data

    NASA Astrophysics Data System (ADS)

    Liu, Qiang; Yan, Chunyan; Xiao, Qing; Yan, Guangjian; Fang, Li

    2012-07-01

    Land surface temperature (LST) is a key parameter in land process research. Many research efforts have been devoted to increase the accuracy of LST retrieval from remote sensing. However, because natural land surface is non-isothermal, component temperature is also required in applications such as evapo-transpiration (ET) modeling. This paper proposes a new algorithm to separately retrieve vegetation temperature and soil background temperature from multiangular thermal infrared (TIR) remote sensing data. The algorithm is based on the localized correlation between the visible/near-infrared (VNIR) bands and the TIR band. This method was tested on the airborne image data acquired during the Watershed Allied Telemetry Experimental Research (WATER) campaign. Preliminary validation indicates that the remote sensing-retrieved results can reflect the spatial and temporal trend of component temperatures. The accuracy is within three degrees while the difference between vegetation and soil temperature can be as large as twenty degrees.

  14. Aerosol optical retrieval and surface reflectance from airborne remote sensing data over land.

    PubMed

    Bassani, Cristiana; Cavalli, Rosa Maria; Pignatti, Stefano

    2010-01-01

    Quantitative analysis of atmospheric optical properties and surface reflectance can be performed by applying radiative transfer theory in the Atmosphere-Earth coupled system, for the atmospheric correction of hyperspectral remote sensing data. This paper describes a new physically-based algorithm to retrieve the aerosol optical thickness at 550 nm (τ(550)) and the surface reflectance (ρ) from airborne acquired data in the atmospheric window of the Visible and Near-Infrared (VNIR) range. The algorithm is realized in two modules. Module A retrieves τ(550) with a minimization algorithm, then Module B retrieves the surface reflectance ρ for each pixel of the image. The method was tested on five remote sensing images acquired by an airborne sensor under different geometric conditions to evaluate the reliability of the method. The results, τ(550) and ρ, retrieved from each image were validated with field data contemporaneously acquired by a sun-sky radiometer and a spectroradiometer, respectively. Good correlation index, r, and low root mean square deviations, RMSD, were obtained for the τ(550) retrieved by Module A (r(2) = 0.75, RMSD = 0.08) and the ρ retrieved by Module B (r(2) ≤ 0.9, RMSD ≤ 0.003). Overall, the results are encouraging, indicating that the method is reliable for optical atmospheric studies and the atmospheric correction of airborne hyperspectral images. The method does not require additional at-ground measurements about at-ground reflectance of the reference pixel and aerosol optical thickness. PMID:22163558

  15. Introduction to an airborne remote sensing system equipped onboard the Chinese marine surveillance plane

    NASA Astrophysics Data System (ADS)

    Gong, Fang; Wang, Difeng; Pan, Delu; Hao, Zengzhou

    2008-10-01

    The airborne remote sensing system onboard the Chinese Marine Surveillance Plane have three scanners including marine airborne multi-spectrum scanner(MAMS), airborne hyper spectral system(AISA+) and optical-electric platform(MOP) currently. MAMS is developed by Shanghai Institute of Technology and Physics CAS with 11 bands from ultraviolet to infrared and mainly used for inversion of oceanic main factors and pollution information, like chlorophyll, sea surface temperature, red tide, etc. The AISA+ made by Finnish Specim company is a push broom system, consist of a high spectrum scanner head, a miniature GPS/INS sensor and data collecting PC. It is a kind of aviation imaging spectrometer and has the ability of ground target imaging and measuring target spectrum characteristic. The MOP mainly supports for object watching, recording and track. It mainly includes 3 equipments: digital CCD with Sony-DXC390, CANON EOS film camera and digital camera Sony F717. This paper mainly introduces these three remote sensing instruments as well as the ground processing information system, involving the system's hardware and software design, related algorithm research, etc.

  16. AIRBORNE, OPTICAL REMOTE SENSING OF METHANE AND ETHANE FOR NATURAL GAS PIPLINE LEAK DETECTION

    SciTech Connect

    Jerry Myers

    2004-05-12

    Ophir Corporation was awarded a contract by the U. S. Department of Energy, National Energy Technology Laboratory under the Project Title ''Airborne, Optical Remote Sensing of Methane and Ethane for Natural Gas Pipeline Leak Detection'' on October 14, 2002. The third six-month technical report contains a summary of the progress made towards finalizing the design and assembling the airborne, remote methane and ethane sensor. The vendor has been chosen and is on contract to develop the light source with the appropriate linewidth and spectral shape to best utilize the Ophir gas correlation software. Ophir has expanded upon the target reflectance testing begun in the previous performance period by replacing the experimental receiving optics with the proposed airborne large aperture telescope, which is theoretically capable of capturing many times more signal return. The data gathered from these tests has shown the importance of optimizing the fiber optic receiving fiber to the receiving optic and has helped Ophir to optimize the design of the gas cells and narrowband optical filters. Finally, Ophir will discuss remaining project issues that may impact the success of the project.

  17. Aerosol Optical Retrieval and Surface Reflectance from Airborne Remote Sensing Data over Land

    PubMed Central

    Bassani, Cristiana; Cavalli, Rosa Maria; Pignatti, Stefano

    2010-01-01

    Quantitative analysis of atmospheric optical properties and surface reflectance can be performed by applying radiative transfer theory in the Atmosphere-Earth coupled system, for the atmospheric correction of hyperspectral remote sensing data. This paper describes a new physically-based algorithm to retrieve the aerosol optical thickness at 550nm (τ550) and the surface reflectance (ρ) from airborne acquired data in the atmospheric window of the Visible and Near-Infrared (VNIR) range. The algorithm is realized in two modules. Module A retrieves τ550 with a minimization algorithm, then Module B retrieves the surface reflectance ρ for each pixel of the image. The method was tested on five remote sensing images acquired by an airborne sensor under different geometric conditions to evaluate the reliability of the method. The results, τ550 and ρ, retrieved from each image were validated with field data contemporaneously acquired by a sun-sky radiometer and a spectroradiometer, respectively. Good correlation index, r, and low root mean square deviations, RMSD, were obtained for the τ550 retrieved by Module A (r2 = 0.75, RMSD = 0.08) and the ρ retrieved by Module B (r2 ≤ 0.9, RMSD ≤ 0.003). Overall, the results are encouraging, indicating that the method is reliable for optical atmospheric studies and the atmospheric correction of airborne hyperspectral images. The method does not require additional at-ground measurements about at-ground reflectance of the reference pixel and aerosol optical thickness. PMID:22163558

  18. Data processing of remotely sensed airborne hyperspectral data using the Airborne Processing Library (APL): Geocorrection algorithm descriptions and spatial accuracy assessment

    NASA Astrophysics Data System (ADS)

    Warren, Mark A.; Taylor, Benjamin H.; Grant, Michael G.; Shutler, Jamie D.

    2014-03-01

    Remote sensing airborne hyperspectral data are routinely used for applications including algorithm development for satellite sensors, environmental monitoring and atmospheric studies. Single flight lines of airborne hyperspectral data are often in the region of tens of gigabytes in size. This means that a single aircraft can collect terabytes of remotely sensed hyperspectral data during a single year. Before these data can be used for scientific analyses, they need to be radiometrically calibrated, synchronised with the aircraft's position and attitude and then geocorrected. To enable efficient processing of these large datasets the UK Airborne Research and Survey Facility has recently developed a software suite, the Airborne Processing Library (APL), for processing airborne hyperspectral data acquired from the Specim AISA Eagle and Hawk instruments. The APL toolbox allows users to radiometrically calibrate, geocorrect, reproject and resample airborne data. Each stage of the toolbox outputs data in the common Band Interleaved Lines (BILs) format, which allows its integration with other standard remote sensing software packages. APL was developed to be user-friendly and suitable for use on a workstation PC as well as for the automated processing of the facility; to this end APL can be used under both Windows and Linux environments on a single desktop machine or through a Grid engine. A graphical user interface also exists. In this paper we describe the Airborne Processing Library software, its algorithms and approach. We present example results from using APL with an AISA Eagle sensor and we assess its spatial accuracy using data from multiple flight lines collected during a campaign in 2008 together with in situ surveyed ground control points.

  19. Intercomparisons between passive and active microwave remote sensing, and hydrological modeling for soil moisture

    NASA Technical Reports Server (NTRS)

    Wood, E. F.; Lin, D.-S.; Mancini, M.; Thongs, D.; Troch, P. A.; Jackson, T. J.; Famiglietti, J. S.; Engman, E. T.

    1993-01-01

    Soil moisture estimations from a distributed hydrological model and two microwave sensors were compared with ground measurements collected during the MAC-HYDRO'90 experiment. The comparison was done with the purpose of evaluating the performance of the hydrological model and examining the limitations of remote sensing techniques used in soil moisture estimation. An image integration technique was used to integrate and analyze rainfall, soil properties, land cover, topography, and remote sensing imagery. Results indicate that the hydrological model and microwave sensors successfully picked up temporal variations of soil moisture and that the spatial soil moisture pattern may be remotely sensed with reasonable accuracy using existing algorithms.

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

    NASA Technical Reports Server (NTRS)

    Evans, Diane L.; Arvidson, Raymond E.

    1991-01-01

    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.

  1. Colorimetric Detection of an Airborne Remote Photocatalytic Reaction Using a Stratified Ag Nanoparticle Sheet.

    PubMed

    Degawa, Ryo; Wang, Pangpang; Tanaka, Daisuke; Park, Susie; Sakai, Nobuyuki; Tatsuma, Tetsu; Okamoto, Koichi; Tamada, Kaoru

    2016-08-16

    Photocatalysts are practically used for decomposition of harmful and fouling organic compounds. Among the photocatalytic reactions, remote oxidation via airborne species is a relatively slow process, so that a sensitive technique for its detection has been awaiting. Here, we investigated an airborne remote photocatalytic reaction of a TiO2 photocatalyst modified with Pt nanoparticles as co-catalysts via the color change caused by a decomposition of a multilayered silver nanoparticle sheet. The silver nanoparticle sheet fabricated by the Langmuir-Schaefer method on a gold substrate exhibits a unique multicolor depending upon the number of layers. The color originates from multiple light trapping in the stratified sheets that has a metamaterial characteristic along with an intra- and interlayer coupling of localized surface plasmon resonance (LSPR). The stepwise decomposition of the sheets was confirmed by the colorimetric data, which exhibited not only a monotonic decrease but also a maximized absorption of light when the film thickness reached the optimal thickness for light trapping or when the oxidation of the Ag core started. Scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and surface plasmon resonance (SPR) spectroscopy data provided a complete view of the decomposition process of this inorganic-organic nanocomposite film, and simulation by the transfer-matrix method explained a simultaneous plasmonic response rationally. The influence of the humidity and gas flow rate on the airborne remote photocatalytic reaction kinetics was examined by this colorimetric detection method, and it suggests that H2O in air plays an essential role in the reaction. PMID:27445001

  2. The first aerosol indirect effect quantified through airborne remote sensing during VOCALS-REx

    NASA Astrophysics Data System (ADS)

    Painemal, D.; Zuidema, P.

    2013-01-01

    The first aerosol indirect effect (1AIE) is investigated using a combination of in situ and remotely-sensed aircraft (NCAR C-130) observations acquired during VOCALS-REx over the southeast Pacific stratocumulus cloud regime. Satellite analyses have previously identified a high albedo susceptibitility to changes in cloud microphysics and aerosols over this region. The 1AIE was broken down into the product of two independently-estimated terms: the cloud aerosol interaction metric ACIτ =dlnτ/dlnNa|LWP , and the relative albedo (A) susceptibility SR-τ =dA/3dlnτ|LWP, with τ and Na denoting retrieved cloud optical thickness and in situ aerosol concentration respectively and calculated for fixed intervals of liquid water path (LWP). ACIτ was estimated by combining in situ Na sampled below the cloud, with τ and LWP derived from, respectively, simultaneous upward-looking broadband irradiance and narrow field-of-view millimeter-wave radiometer measurements, collected at 1 Hz during four eight-hour daytime flights by the C-130 aircraft. ACIτ values were typically large, close to the physical upper limit (0.33), with a modest increase with LWP. The high ACIτ values slightly exceed values reported from many previous in situ airborne studies in pristine marine stratocumulus and reflect the imposition of a LWP constraint and simultaneity of aerosol and cloud measurements. SR-τ increased with LWP and τ, reached a maximum SR-τ (0.086) for LWP (τ) of 58 g m-2 (~14), and decreased slightly thereafter. The 1AIE thus increased with LWP and is comparable to a radiative forcing of -3.2- -3.8 W m-2 for a 10% increase in Na, exceeding previously-reported global-range values. The aircraft-derived values are consistent with satellite estimates derived from instantaneous, collocated Clouds and the Earth's Radiant Energy System (CERES) albedo and MOderate resolution Imaging Spectroradiometer (MODIS)-retrieved droplet number concentrations at 50 km resolution. The consistency of

  3. Calibration of passive remote observing optical and microwave instrumentation; Proceedings of the Meeting, Orlando, FL, Apr. 3-5, 1991

    NASA Technical Reports Server (NTRS)

    Guenther, Bruce W. (Editor)

    1991-01-01

    Various papers on the calibration of passive remote observing optical and microwave instrumentation are presented. Individual topics addressed include: on-board calibration device for a wide field-of-view instrument, calibration for the medium-resolution imaging spectrometer, cryogenic radiometers and intensity-stabilized lasers for EOS radiometric calibrations, radiometric stability of the Shuttle-borne solar backscatter ultraviolet spectrometer, ratioing radiometer for use with a solar diffuser, requirements of a solar diffuser and measurements of some candidate materials, reflectance stability analysis of Spectralon diffuse calibration panels, stray light effects on calibrations using a solar diffuser, radiometric calibration of SPOT 23 HRVs, surface and aerosol models for use in radiative transfer codes. Also addressed are: calibrated intercepts for solar radiometers used in remote sensor calibration, radiometric calibration of an airborne multispectral scanner, in-flight calibration of a helicopter-mounted Daedalus multispectral scanner, technique for improving the calibration of large-area sphere sources, remote colorimetry and its applications, spatial sampling errors for a satellite-borne scanning radiometer, calibration of EOS multispectral imaging sensors and solar irradiance variability.

  4. Calibration of passive remote observing optical and microwave instrumentation; Proceedings of the Meeting, Orlando, FL, Apr. 3-5, 1991

    NASA Astrophysics Data System (ADS)

    Guenther, Bruce W.

    Various papers on the calibration of passive remote observing optical and microwave instrumentation are presented. Individual topics addressed include: on-board calibration device for a wide field-of-view instrument, calibration for the medium-resolution imaging spectrometer, cryogenic radiometers and intensity-stabilized lasers for EOS radiometric calibrations, radiometric stability of the Shuttle-borne solar backscatter ultraviolet spectrometer, ratioing radiometer for use with a solar diffuser, requirements of a solar diffuser and measurements of some candidate materials, reflectance stability analysis of Spectralon diffuse calibration panels, stray light effects on calibrations using a solar diffuser, radiometric calibration of SPOT 23 HRVs, surface and aerosol models for use in radiative transfer codes. Also addressed are: calibrated intercepts for solar radiometers used in remote sensor calibration, radiometric calibration of an airborne multispectral scanner, in-flight calibration of a helicopter-mounted Daedalus multispectral scanner, technique for improving the calibration of large-area sphere sources, remote colorimetry and its applications, spatial sampling errors for a satellite-borne scanning radiometer, calibration of EOS multispectral imaging sensors and solar irradiance variability. (For individual items see A93-23576 to A93-23603)

  5. Fourth Airborne Geoscience Workshop

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The focus of the workshop was on how the airborne community can assist in achieving the goals of the Global Change Research Program. The many activities that employ airborne platforms and sensors were discussed: platforms and instrument development; airborne oceanography; lidar research; SAR measurements; Doppler radar; laser measurements; cloud physics; airborne experiments; airborne microwave measurements; and airborne data collection.

  6. Passive microwave remote and in situ measurements of Arctic and subarctic snow covers in Alaska

    NASA Technical Reports Server (NTRS)

    Hall, D. K.; Chang, A. T. C.; Foster, J. L.; Sturm, M.; Chacho, E.; Benson, C. S.; Garbeil, H.

    1991-01-01

    Airborne and satellite passive microwave measurements acquired simultaneously with ground measurements of depth, density, and stratigraphy of the snow in central and northern Alaska between March 11 and 19, 1988, are reported. A good correspondence in brightness temperature (TB) trends between the aircraft and satellite data was found. An expected inverse correlation between depth hoar thickness and TB was not found to be strong. A persistent TB minimum in both the aircraft and the satellite data was detected along the northern foothills of the Brooks Range. In an area located at about 68 deg 60 min N, 149 deg 20 min W, the TB as recorded from the aircraft microwave sensor dropped by 55 K. Satellite microwave measurements showed a TB decrease of up to 45 K at approximately the same location. An examination of microwave satellite data from 1978 to 1987 revealed that similar low late-winter values were found in approximately the same locations as those observed in March 1988.

  7. Overview of hyperspectral remote sensing for mapping marine benthic habitats from airborne and underwater sensors

    NASA Astrophysics Data System (ADS)

    Dierssen, Heidi M.

    2013-09-01

    The seafloor, with its diverse and dynamic benthic habitats varying on meter to centimeter scales, is difficult to accurately monitor with traditional techniques. The technology used to build imaging spectrometers has rapidly advanced in recent years with the advent of smaller sensors and better signal-to-noise capabilities that has facilitated their use in mapping fine-scale benthic features. Here, the use of such sensors for hyperspectral remote sensing of the seafloor from both airborne and underwater platforms is discussed. Benthic constituents provide a so-called optical fingerprint with spectral properties that are often too subtle to be discerned with simple color photographs or multichannel spectrometers. Applications include the recent field validation of the airborne Portable Remote Imaging SpectroMeter (PRISM), a new imaging sensor package optimized for coastal ocean processes in Elkorn Slough California. In these turbid sediment-laden waters, only subtle spectral differences differentiate seafloor with sediment from that with eelgrass. The ultimate goal is to provide robust radiometric approaches that accurately consider light attenuation by the water column and are able to be applied to diverse habitats without considerable foreknowledge.

  8. AIRBORNE, OPTICAL REMOTE SENSING OF METHANE AND ETHANE FOR NATURAL GAS PIPELINE LEAK DETECTION

    SciTech Connect

    Jerry Myers

    2003-05-13

    Ophir Corporation was awarded a contract by the U. S. Department of Energy, National Energy Technology Laboratory under the Project Title ''Airborne, Optical Remote Sensing of Methane and Ethane for Natural Gas Pipeline Leak Detection'' on October 14, 2002. This six-month technical report summarizes the progress for each of the proposed tasks, discusses project concerns, and outlines near-term goals. Ophir has completed a data survey of two major natural gas pipeline companies on the design requirements for an airborne, optical remote sensor. The results of this survey are disclosed in this report. A substantial amount of time was spent on modeling the expected optical signal at the receiver at different absorption wavelengths, and determining the impact of noise sources such as solar background, signal shot noise, and electronic noise on methane and ethane gas detection. Based upon the signal to noise modeling and industry input, Ophir finalized the design requirements for the airborne sensor, and released the critical sensor light source design requirements to qualified vendors. Responses from the vendors indicated that the light source was not commercially available, and will require a research and development effort to produce. Three vendors have responded positively with proposed design solutions. Ophir has decided to conduct short path optical laboratory experiments to verify the existence of methane and absorption at the specified wavelength, prior to proceeding with the light source selection. Techniques to eliminate common mode noise were also evaluated during the laboratory tests. Finally, Ophir has included a summary of the potential concerns for project success and has established future goals.

  9. Remote Sensing of Wind Fields and Aerosol Distribution with Airborne Scanning Doppler Lidar

    NASA Technical Reports Server (NTRS)

    Rothermel, Jeffry; Cutten, Dean R.; Johnson, Steven C.; Jazembski, Maurice; Arnold, James E. (Technical Monitor)

    2001-01-01

    The coherent Doppler laser radar (lidar), when operated from an airborne platform, is a unique tool for the study of atmospheric and surface processes and features. This is especially true for scientific objectives requiring measurements in optically-clear air, where other remote sensing technologies such as Doppler radar are typically at a disadvantage. The atmospheric lidar remote sensing groups of several US institutions, led by Marshall Space Flight Center, have developed an airborne coherent Doppler lidar capable of mapping the wind field and aerosol structure in three dimensions. The instrument consists of an eye-safe approx. 1 Joule/pulse lidar transceiver, telescope, scanner, inertial measurement unit, and flight computer system to orchestrate all subsystem functions and tasks. The scanner is capable of directing the expanded lidar beam in a variety of ways, in order to extract vertically-resolved wind fields. Horizontal resolution is approx. 1 km; vertical resolution is even finer. Winds are obtained by measuring backscattered, Doppler-shifted laser radiation from naturally-occurring aerosol particles (of order 1 micron diameter). Measurement coverage depends on aerosol spatial distribution and composition. Velocity accuracy has been verified to be approx. 1 meter per second. A variety of applications have been demonstrated during the three flight campaigns conducted during 1995-1998. Examples will be shown during the presentation. In 1995, boundary layer winds over the ocean were mapped with unprecedented resolution. In 1996, unique measurements were made of. flow over the complex terrain of the Aleutian Islands; interaction of the marine boundary layer jet with the California coastal mountain range; a weak dry line in Texas - New Mexico; the angular dependence of sea surface scattering; and in-flight radiometric calibration using the surface of White Sands National Monument. In 1998, the first measurements of eyewall and boundary layer winds within a

  10. Remote Sensing of Wind Fields and Aerosol Distributions with Airborne Scanning Doppler Lidar

    NASA Technical Reports Server (NTRS)

    Rothermel, Jeffry; Cutten, Dean R.; Goodman, H. Michael (Technical Monitor)

    2000-01-01

    The coherent Doppler lidar, when operated from an airborne platform, offers a unique measurement capability for study of atmospheric and surface processes and feature. This is especially true for scientific objectives requiring measurements in optically-clear air, where other remote sensing technologies such as Doppler radar are at a disadvantage in terms of spatial resolution and coverage. The atmospheric lidar remote sensing groups of several US institutions, led by Marshall Space Flight Center, have developed an airborne coherent Doppler lidar capable of mapping the wind field and aerosol structure in three dimensions. The instrument consists of about a 1 Joule/pulse (eyesafe) lidar transceiver, telescope, scanner, inertial measurement unit, and operations control system to orchestrate all subsystem functions and tasks. The scanner is capable of directing the expanded lidar beam in a variety of ways, in order to extract vertically resolved wind fields. Horizontal resolution is about 1 km; vertical resolution is even finer. Winds are obtained by measuring backscattered, Doppler-shifted laser radiation from naturally-occurring aerosol particles (on an order of 1 micron in diameter). Measurement coverage depends on aerosol spatial distribution and concentration. Velocity accuracy has been verified to be about 1 m/s. A variety of applications has been demonstrated during the three flight campaigns conducted during 1995-1998. Examples will be shown during the presentation. In 1995, boundary layer winds over the ocean were mapped with unprecedented resolution. In 1996, unique measurements were made of flow over the complex terrain of the Aleutian Islands; interaction of the marine boundary layer jet with the California coastal mountain range; a weak dry line in Texas - New Mexico; an upper tropospheric jet stream; the angular dependence of sea surface scattering; and in-flight radiometric calibration using the surface of White Sands National Monument. In 1998, the

  11. Application research of using CASI/SASI airborne hyperspectral remote sensing on lithology identification

    NASA Astrophysics Data System (ADS)

    Zhou, Jiajing; Qin, Kai

    2016-04-01

    Remote sensing provides an advanced method for lithology identification, which is one of the important research fields in geological prospecting. In theory, each lithology is of individual spectrum characteristics. Based on the spectral differences between them, we can identify different lithologies by remote sensing images. At present, the studies on lithology identification by remote sensing are primarily conducted on the multispectral images, such as Landsat 7 ETM+, SPOT-5, QuickBird and WorldView-2. Hyperspectral remote sensing images provide richer information, making it easier to identify the lithologies, but studied rarely. CASI/SASI is an airborne hyperspectral system covering a wavelength range of 0.38-2.45μm. With hundreds of bands, the hyperspectral images are useful to identify the spectrum characteristics of lithology. In addition, images are of high spatial resolution, with CASI of about 1m and SASI of about 2-2.5m, which make lithology identification more accurate. CASI/SASI hyperspectral data was collected in Beishan metallogenic belt in northwest China, as same as the ground spectral data of the lithologies. After data preprocessing, we divided different lithologies using CASI/SASI hyperspectral images and lithology spectrum, identified some important lithologies related to mineralization, and successfully found a few new ore clues.

  12. Microwave remote sensing of snow experiment description and preliminary results

    NASA Technical Reports Server (NTRS)

    Ulaby, F. T. (Principal Investigator); Stiles, W. H.; Hanson, B. C.

    1977-01-01

    The active and passive microwave responses to snow were investigated at a site near Steamboat Springs, Colorado during the February and March winter months. The microwave equipment was mounted atop truck-mounted booms. Data were acquired at numerous frequencies, polarizations, and angles of incidence for a variety of snow conditions. The experiment description, the characteristics of the microwave and ground truth instruments, and the results of a preliminary analysis of a small portion of the total data volume acquired in Colorado are documented.

  13. Airborne Deployment and Calibration of Microwave Atmospheric Sounder on 6U CubeSat

    NASA Astrophysics Data System (ADS)

    Padmanabhan, S.; Brown, S. T.; Lim, B.; Kangaslahti, P.; Russell, D.; Stachnik, R. A.

    2015-12-01

    To accurately predict how the distribution of extreme events may change in the future we need to understand the mechanisms that influence such events in our current climate. Our current observing system is not well-suited for observing extreme events globally due to the sparse sampling and in-homogeneity of ground-based in-situ observations and the infrequent revisit time of satellite observations. Observations of weather extremes, such as extreme precipitation events, temperature extremes, tropical and extra-tropical cyclones among others, with temporal resolution on the order of minutes and spatial resolution on the order of few kms (<10 kms), are required for improved forecasting of extreme weather events. We envision a suite of low-cost passive microwave sounding and imaging sensors on CubeSats that would work in concert with traditional flagship observational systems, such as those manifested on large environmental satellites (i.e. JPSS,WSF,GCOM-W), to monitor weather extremes. A 118/183 GHz sensor would enable observations of temperature and precipitation extremes over land and ocean as well as tropical and extra-tropical cyclones. This proposed project would enable low cost, compact radiometer instrumentation at 118 and 183 GHz that would fit in a 6U Cubesat with the objective of mass-producing this design to enable a suite of small satellites to image the key geophysical parameters needed to improve prediction of extreme weather events. We take advantage of past and current technology developments at JPL viz. HAMSR (High Altitude Microwave Scanning Radiometer), Advanced Component Technology (ACT'08) to enable low-mass, low-power high frequency airborne radiometers. In this paper, we will describe the design and implementation of the 118 GHz temperature sounder and 183 GHz humidity sounder on the 6U CubeSat. In addition, we will discuss the maiden airborne deployment of the instrument during the Plain Elevated Convection at Night (PECAN) experiment. The

  14. Synergy between optical and microwave remote sensing to derive soil and vegetation parameters from MAC Europe 1991 Experiment

    NASA Technical Reports Server (NTRS)

    Taconet, O.; Benallegue, M.; Vidal, A.; Vidal-Madjar, D.; Prevot, L.; Normand, M.

    1993-01-01

    The ability of remote sensing for monitoring vegetation density and soil moisture for agricultural applications is extensively studied. In optical bands, vegetation indices (NDVI, WDVI) in visible and near infrared reflectances are related to biophysical quantities as the leaf area index, the biomass. In active microwave bands, the quantitative assessment of crop parameters and soil moisture over agricultural areas by radar multiconfiguration algorithms remains prospective. Furthermore the main results are mostly validated on small test sites, but have still to be demonstrated in an operational way at a regional scale. In this study, a large data set of radar backscattering has been achieved at a regional scale on a French pilot watershed, the Orgeval, along two growing seasons in 1988 and 1989 (mainly wheat and corn). The radar backscattering was provided by the airborne scatterometer ERASME, designed at CRPE, (C and X bands and HH and VV polarizations). Empirical relationships to estimate water crop and soil moisture over wheat in CHH band under actual field conditions and at a watershed scale are investigated. Therefore, the algorithms developed in CHH band are applied for mapping the surface conditions over wheat fields using the AIRSAR and TMS images collected during the MAC EUROPE 1991 experiment. The synergy between optical and microwave bands is analyzed.

  15. A survey of natural aggregate properties and characteristics important in remote sensing and airborne geophysics

    USGS Publications Warehouse

    Knepper, D.H.; Langer, W.H.; Miller, S.

    1995-01-01

    Natural aggregate is vital to the construction industry. Although natural aggregate is a high volume/low value commodity that is abundant, new sources are becoming increasingly difficult to find and develop because of rigid industry specifications, political considerations, development and transportation costs, and environmental concerns. There are two primary sources of natural aggregate: (1) exposed or near-surface bedrock that can be crushed, and (2) deposits of sand and gravel. Remote sensing and airborne geophysics detect surface and near-surface phenomena, and may be useful for detecting and mapping potential aggregate sources; however, before a methodology for applying these techniques can be developed, it is necessary to understand the type, distribution, physical properties, and characteristics of natural aggregate deposits. The distribution of potential aggregate sources is closely tied to local geologic history. Conventional exploration for natural aggregate deposits has been largely a ground-based operation, although aerial photographs and topographic maps have been extensively used to target possible deposits. Today, the exploration process also considers factors such as the availability of the land, space and water supply for processing, political and environmental factors, and distance from the market; exploration and planning cannot be separated. There are many physical properties and characteristics by which to judge aggregate material for specific applications; most of these properties and characteristics pertain only to individual aggregate particles. The application of remote sensing and airborne geophysical measurements to detecting and mapping potential aggregate sources, however, is based on intrinsic bulk physical properties and extrinsic characteristics of the deposits that can be directly measured, mathematically derived from measurement, or interpreted with remote sensing and geophysical data. ?? 1995 Oxford UniversityPress.

  16. Estimating vegetation optical depth using L-band passive microwave airborne data in HiWATER

    NASA Astrophysics Data System (ADS)

    Wang, Qi; Chai, Linna

    2014-11-01

    In this study, a relationship between polarization differences of soil emissivity at different incidence angles was constructed from a large quantity of simulated soil emissivity based on the Advanced Integrated Emission Model (AIEM) input parameters include: a frequency of 1.4 GHz (L-band), incident angles varying from 1°to 60° at a 1° interval, a wide range of soil moisture content and land surface roughness parameters. Then, we used this relationship and the ω-τ zero-order radiation transfer model to develop an inversion method of low vegetation optical depth at L-band, this work were under the assumption that there was no significant polarization difference between the vegetation signals. Based on this inversion method of low vegetation optical depth, we used the land surface passive microwave brightness temperature of Heihe Watershed obtained by airborne Polarimetric L-band Multibeam Radiometer (PLMR) in 2012 Heihe Watershed Allied Telemetry Experimental Research (HiWATER) to retrieve the corn optical depth in the flight areas, then the results were compared with the measured corn LAI. Results show that the retrieved corn optical depths were consisted with the measured LAI of corn. It proved that the corn optical depth inversion method proposed in this study was feasible. Moreover, the method was promising to apply to the satellite observations.

  17. The first aerosol indirect effect quantified through airborne remote sensing during VOCALS-REx

    NASA Astrophysics Data System (ADS)

    Painemal, D.; Zuidema, P.

    2012-09-01

    The first aerosol indirect effect (1AIE) is investigated using a combination of in situ and remotely-sensed aircraft (NCAR C-130) observations acquired during VOCALS-REx over the Southeast Pacific stratocumulus cloud regime. Satellite analyses have previously identified a high albedo susceptibitility to changes in cloud microphysics and aerosols over this region. The 1AIE was broken down into the product of two independently-estimated terms: the cloud aerosol interaction metric ACIτ =dln τ/dln Na|LWP, and the relative albedo (A) susceptibility SR-τ = dA/3dln τ|LWP, with τ and Na denoting retrieved cloud optical thickness and in-situ aerosol concentration, respectively and calculated for fixed intervals of liquid water path (LWP). ACIτ was estimated by combining in-situ Na sampled below the cloud, with τ and LWP derived from, respectively, simultaneous upward-looking broadband irradiance and narrow field-of-view millimeter-wave radiometer measurements, collected at 1 Hz during four eight-hour daytime flights by the C-130 aircraft. ACIτ values were typically large, close to the physical upper limit (0.33), increasing with LWP. The high ACIτ values were in agreement with other in-situ airborne studies in pristine marine stratocumulus and reflect the imposition of a LWP constraint and simultaneity of aerosol and cloud measurements. SR-τ increased with LWP and τ, reached a maximum SR-τ (0.086) for LWP (τ) of 58 g m-2 (13-14), decreasing slightly thereafter. The net first aerosol indirect effect thus increased over the LWP range of 30-80 g m-2. These values were consistent with satellite estimates derived from instantaneous, collocated CERES albedo and MODIS-retrieved droplet number concentrations at 50 km resolution. The consistency of the airborne and satellite estimates (for airborne remotely sensed Nd < 1100 cm-3), despite their independent approaches, differences in observational scales, and retrieval assumptions, is hypothesized to reflect the robust

  18. Satellite Remote Sensing: Passive-Microwave Measurements of Sea Ice

    NASA Technical Reports Server (NTRS)

    Parkinson, Claire L.; Zukor, Dorothy J. (Technical Monitor)

    2001-01-01

    Satellite passive-microwave measurements of sea ice have provided global or near-global sea ice data for most of the period since the launch of the Nimbus 5 satellite in December 1972, and have done so with horizontal resolutions on the order of 25-50 km and a frequency of every few days. These data have been used to calculate sea ice concentrations (percent areal coverages), sea ice extents, the length of the sea ice season, sea ice temperatures, and sea ice velocities, and to determine the timing of the seasonal onset of melt as well as aspects of the ice-type composition of the sea ice cover. In each case, the calculations are based on the microwave emission characteristics of sea ice and the important contrasts between the microwave emissions of sea ice and those of the surrounding liquid-water medium.

  19. Implications of RFI at L-Band on Passive Microwave Remote Sensing of Soil Moisture from Space: Experience with ESTAR During SGP97

    NASA Technical Reports Server (NTRS)

    LeVine, David M.

    2000-01-01

    Passive microwave remote sensing in the protected band at 1.413 GHz (L-band) is important for monitoring parameters of the ocean and land surface such as soil moisture and sea surface salinity. These parameters are needed for understanding energy exchange between the surface and atmosphere and therefore are important for improving our understanding of weather and climate change. Although the band at 1.413 GHz is protected for passive use, airborne radiometers experience problems with RFI. For example, during the Southern Great Plains Experiment (1997) the ESTAR radiometer experienced significant RFI associated with airports, presumably air traffic control radar. This is a potential problem for future sensors in space planned for remote sensing of the earth surface in this frequency band.

  20. Electrically scanning microwave radiometers. [for satellite-borne remote sensing

    NASA Technical Reports Server (NTRS)

    Mix, R. F.

    1974-01-01

    The electrically scanning microwave radiometer (ESMR) developed for and currently used onboard the Nimbus 5 meteorological satellite is described, along with the ESMR developed for the Nimbus F satellite. They serve for synoptic mapping of microwave emissions from the earth's surface, the instrument on Nimbus 5 measuring these emissions at a wavelength of 1.55 cm (19.35 GHz) and the instrument on Nimbus F, at a wavelength of 0.81 cm (37 GHz). Radiative transfer characteristics measured at these wavelengths are sufficiently different from IR measurements to permit derivation and interpretation of unique meteorological, geomorphological, and oceanographic data.

  1. [Remote sensing of chlorophyll fluorescence at airborne level based on unmanned airship platform and hyperspectral sensor].

    PubMed

    Yang, Pei-Qi; Liu, Zhi-Gang; Ni, Zhuo-Ya; Wang, Ran; Wang, Qing-Shan

    2013-11-01

    The solar-induced chlorophyll fluorescence (ChlF) has a close relationship with photosynthetic and is considered as a probe of plant photosynthetic activity. In this study, an airborne fluorescence detecting system was constructed by using a hyperspectral imager on board an unmanned airship. Both Fraunhofer Line Discriminator (FLD) and 3FLD used to extract ChlF require the incident solar irradiance, which is always difficult to receive at airborne level. Alternative FLD (aFLD) can overcome the problem by selecting non-fluorescent emitter in the image. However, aFLD is based on the assumption that reflectance is identical around the Fraunhofer line, which is not realistic. A new method, a3FLD, is proposed, which assumes that reflectance varies linearly with the wavelength around Fraunhofer line. The result of simulated data shows that ChlF retrieval error of a3FLD is significantly lower than that of aFLD when vegetation reflectance varies near the Fraunhofer line. The results of hyperspectral remote sensing data with the airborne fluorescence detecting system show that the relative values of retrieved ChlF of 5 kinds of plants extracted by both aFLD and a3FLD are consistent with vegetation growth stage and the ground-level ChlF. The ChlF values of aFLD are about 15% greater than a3FLD. In addition, using aFLD, some non-fluorescent objects have considerable ChlF value, while a3FLD can effectively overcome the problem.

  2. [Remote sensing of chlorophyll fluorescence at airborne level based on unmanned airship platform and hyperspectral sensor].

    PubMed

    Yang, Pei-Qi; Liu, Zhi-Gang; Ni, Zhuo-Ya; Wang, Ran; Wang, Qing-Shan

    2013-11-01

    The solar-induced chlorophyll fluorescence (ChlF) has a close relationship with photosynthetic and is considered as a probe of plant photosynthetic activity. In this study, an airborne fluorescence detecting system was constructed by using a hyperspectral imager on board an unmanned airship. Both Fraunhofer Line Discriminator (FLD) and 3FLD used to extract ChlF require the incident solar irradiance, which is always difficult to receive at airborne level. Alternative FLD (aFLD) can overcome the problem by selecting non-fluorescent emitter in the image. However, aFLD is based on the assumption that reflectance is identical around the Fraunhofer line, which is not realistic. A new method, a3FLD, is proposed, which assumes that reflectance varies linearly with the wavelength around Fraunhofer line. The result of simulated data shows that ChlF retrieval error of a3FLD is significantly lower than that of aFLD when vegetation reflectance varies near the Fraunhofer line. The results of hyperspectral remote sensing data with the airborne fluorescence detecting system show that the relative values of retrieved ChlF of 5 kinds of plants extracted by both aFLD and a3FLD are consistent with vegetation growth stage and the ground-level ChlF. The ChlF values of aFLD are about 15% greater than a3FLD. In addition, using aFLD, some non-fluorescent objects have considerable ChlF value, while a3FLD can effectively overcome the problem. PMID:24555390

  3. Remote, non-contacting personnel bio-identification using microwave radiation

    NASA Technical Reports Server (NTRS)

    McGrath, William R. (Inventor); Talukder, Ashit (Inventor)

    2011-01-01

    A system to remotely identify a person by utilizing a microwave cardiogram, where some embodiments segment a signal representing cardiac beats into segments, extract features from the segments, and perform pattern identification of the segments and features with a pre-existing data set. Other embodiments are described and claimed.

  4. Actual evapotranspiration estimation by means of airborne and satellite remote sensing data

    NASA Astrophysics Data System (ADS)

    Ciraolo, Giuseppe; D'Urso, Guido; Minacapilli, Mario

    2006-09-01

    During the last the two decades, the scientific community developed detailed mathematical models for simulating land surface energy fluxes and crop evapotranspiration rates by means of a energy balance approach. These models can be applied in large areas and with a spatial distributed approach using surface brightness temperature and some ancillary data retrieved from satellite/airborne remote sensed imagery. In this paper a district scale application in combination with multispectral (LandaSat 7 TM data) and hyperspectral airborne MIVIS data has been carried out to test the potentialities of two different energy balance models to estimate evapotranspiration fluxes from a set of typical Mediterranean crops (wine, olive, citrus). The impact of different spatial and radiometric resolutions of MIVIS (3m x 3m) and LandSat (60m x 60m) on models-derived fluxes has been investigated to understand the roles and the main conceptual differences between the two models which respectively use a "single-layer" (SEBAL) and a "two-layer" (TS) schematisation.

  5. Microwave Dielectric Properties of Soil and Vegetation and Their Estimation From Spaceborne Radar

    NASA Technical Reports Server (NTRS)

    Dobson, M. Craig; McDonald, Kyle C.

    1996-01-01

    This paper is largely tutorial in nature and provides an overview of the microwave dielectric properties of certain natural terrestrial media (soils and vegetation) and recent results in estimating these properties remotely from airborne and orbital synthetic aperture radar (SAR).

  6. Satellite remote sensing of global rainfall using passive microwave radiometry

    SciTech Connect

    Ferriday, J.G.

    1994-12-31

    Global rainfall over land and ocean is estimated using measurements of upwelling microwaves by a satellite passive microwave radiometer. Radiative transfer calculations through a cloud model are used to parameterize an inversion technique for retrieving rain rates from brightness temperatures measured by the Special Sensor Microwave Imager (SSM/I). The rainfall retrieval technique is based on the interaction between multi-spectral microwave radiances and millimeter sized liquid and frozen hydrometeors distributed in the satellite`s field of view. The rain rate algorithm is sensitive to both hydrometeor emission and scattering while being relatively insensitive to extraneous atmospheric and surface effects. Separate formulations are used over ocean and land to account for different background microwave characteristics and the algorithm corrects for inhomogeneous distributions of rain rates within the satellite`s field of view. Estimates of instantaneous and climate scale rainfall are validated through comparisons with modeled clouds, surface radars, rain gauges and alternative satellite estimates. The accuracy of the rainfall estimates is determined from a combination of validation comparisons, theoretical sampling error calculations, and modeled sensitivity to variations in atmospheric and surface radiative properties. An error budget is constructed for both instantaneous rain rates and climate scale global estimates. At a one degree resolution, the root mean square errors in instantaneous rain rate estimates are 13% over ocean and 20% over land. The root mean square errors in global rainfall totals over a four month period are found to be 46% over ocean and 63% over land. Global rainfall totals are computed on a monthly scale for a three year period from 1987 to 1990. The time series is analyzed for climate scale rainfall distribution and variability.

  7. Proposed Definitions of Some Technical Terms Frequently Used in Microwave Radiometry for Remote Sensing

    NASA Technical Reports Server (NTRS)

    Shiue, James C.; Zukor, Dorothy J. (Technical Monitor)

    2000-01-01

    The use of microwave radiometry for remote sensing is a relatively young field. As a result, there are no standard definitions of many frequently used technical terms; a lot of which are conventional usages carried-over from optical remote sensing, and a lot more are shared with electrical or microwave engineering. Sometimes the divergent notions and assumptions originating from a different field may cause ambiguity or confusions. It is proposed that we establish a list of frequently used terms, together with their 'standard' definitions and hope that they will gradually gain general acceptance by the remote sensing community. It would be even more useful if the IEEE community can set up a standard committee of sort to develop and maintain the standards. To minimize the effort, the existing terms should be kept or reinterpreted as much as possible. For example, the term 'Instantaneous Field of View' (IFOV), originally coming from the optical remote sensing field, is now appearing in microwave remote sensing literature frequently. The IFOV refers to the 'beam width' or the 'diameter' of the beam's geometrical projection on earth surface. Since the definition of 'beam width' is different for an optical system versus a microwave antenna, the use of IFOV in microwave radiometry needed to be clarified. Also, the meaning of the IFOV will be different depending upon whether the beam is scanning or not, and how the scanning takes place, e.g. 'continuous scanning' vs 'stare-and-step scan.' From this one term alone, it is clear that more subtle meanings must be spell out in detail and a 'standard' definition would help in understanding and comparing systems and data in the literature. A selected list of terms with their suggested definitions will be discussed in this presentation.

  8. Airborne full polarization radiometry using the MSFC Advanced Microwave Precipitation Radiometer (AMPR)

    NASA Technical Reports Server (NTRS)

    Gasiewski, Al J.; Kunkee, D. B.

    1993-01-01

    The applications of vertically and horizontally polarized brightness temperatures in both atmospheric and surface remote sensing have been long recognized by many investigators, particularly those studying SMMR and SSM/I data. Here, the large contrast between the first two Stokes' parameters (T(sub V) and T(sub H)) can be used for detection of sea ice, measurement of ocean surface wind speed, and measurement of cloud and water vapor opacity. High-resolution aircraft data from instruments such as the NASA/MSFC AMPR is crucial for verifying radiative transfer models and developing retrieval algorithms. Currently, the AMPR is outfitted with single-polarization channels at 10, 18, 37 and 85 GHz. To increase its utility, it is proposed that additional orthogonal linearly polarized channels be added to the AMPR. Since the AMPR's feedhorns are already configured for dual orthogonal linearly polarized modes, this would require only a duplication of the currently existing receivers. To circumvent the resulting polarization basis skew caused by the cross-track scanning mechanism, the technique of Electronic Polarization Basis Rotation is proposed to be implemented. Implementation of EPBR requires precise measurement of the third Stokes parameter and will eliminate polarization skew by allowing the feedhorn basis skew angle to be corrected in software. In addition to upgrading AMPR to dual polarization capability (without skew), the modifications will provide an opportunity to demonstrate EPBR on an airborne platform. This is a highly desirable intermediate step prior to satellite implementation.

  9. Mapping mine tailings using airborne geophysical and hyperspectral remote sensing data

    NASA Astrophysics Data System (ADS)

    Shang, Jiali

    Mine tailings are the waste products from mining operations. Most mine tailings contain a considerable amount of reactive sulphides which can cause acid mine drainage (AMD) when exposed to air and water. AMD constitutes a threat both to the environment and to public health. Increased awareness of AMD has led to growing activities in mine-tailing monitoring and reclamation worldwide. Mining companies in Canada are required to provide information to provincial governments about their waste disposal and control activities. There is an urgent need to develop new automated ways to provide information on short- to long-term evolution of tailings, thus enabling the mining companies to monitor their tailings more effectively. The overall goal of the thesis is to explore the potential of hyperspectral remote sensing and geophysical techniques for mapping variations within and immediately outside of the tailings. Data used for this study are from three sources: airborne geophysical data, hyperspectral casi and Probe-1 data, and field data. This study has contributed to both the remote sensing data analysis techniques and the understanding of mine-tailing surface and subsurface processes. Specifically, this study has the following important findings: (1) Airborne magnetic and electromagnetic data can provide information regarding the subsurface distribution of mine tailings on the basis of sulphide mineral content. A procedure has been developed in this study to use these data sources for rapidly surveying large tailings areas. This procedure can minimize expenditures for mining companies when designing remedial plans for the closure of the mines. This study has also identified regions of enhanced conductivity that extend beyond the tailing containment area. This information indicates seepage pathways, and is important for monitoring the effectiveness of tailing containment structures. (2) High-spatial-resolution hyperspectral casi (Compact Airborne Spectrographic Imagery

  10. Airborne Thermal Remote Sensing for Estimation of Groundwater Discharge to a River.

    PubMed

    Liu, Chuankun; Liu, Jie; Hu, Yue; Wang, Heshun; Zheng, Chunmiao

    2016-05-01

    Traditional methods for studying surface water and groundwater interactions have usually been limited to point measurements, such as geochemical sampling and seepage measurement. A new methodology is presented for quantifying groundwater discharge to a river, by using river surface temperature data obtained from airborne thermal infrared remote sensing technology. The Hot Spot Analysis toolkit in ArcGIS was used to calculate the percentage of groundwater discharge to a river relative to the total flow of the river. This methodology was evaluated in the midstream of the Heihe River in the arid and semiarid northwest China. The results show that the percentage of groundwater discharge relative to the total streamflow was as high as 28%, which is in good agreement with the results from previous geochemical studies. The data analysis methodology used in this study is based on the assumption that the river water is fully mixed except in the areas of extremely low flow velocity, which could lead to underestimation of the amount of groundwater discharge. Despite this limitation, this remote sensing-based approach provides an efficient means of quantifying the surface water and groundwater interactions on a regional scale.

  11. High-precision geometric correction of airborne remote sensing revisited: the multiquadric interpolation

    NASA Astrophysics Data System (ADS)

    Ehlers, Manfred; Fogel, David N.

    1994-12-01

    For a geographic analysis of multispectral scanner data from aircraft and their integration in spatial databases and geographic integration systems (GIS), geometric registration/rectification of the scanner imagery is required as a first step. Usually, one has to rely on global mapping functions such as polynomial equations as provided by most commercial image processing systems. These techniques have been proven to be very effective and accurate for satellite images. However, there are a umber of shortcomings when this method is applied to aircraft data. We see the multiquadric interpolation method as a promising alternative. The multiquadric function was first developed for the interpolation of irregular surfaces. It could be modified, however, to be used for image correction of remotely sensed data. In this form, it is particularly suited for the rectification of remote sensing images of large scale and locally varying geometric distortions. The multiquadric interpolation method yields a perfect fit at the used control points (CPs). With this, it is necessary to withhold independent test points that can be used for accuracy assessment. Within the registration/rectification process, all CPs contribute to the geometric warping of any given pixel in the image. Their effects, however, are weighted inversely to the distances between CPs and the current pixel location. The paper presents the multiquadric interpolation techniques and demonstrates successful application with airborne scanner data.

  12. An Airborne A-Band Spectrometer for Remote Sensing Of Aerosol and Cloud Optical Properties

    NASA Technical Reports Server (NTRS)

    Pitts, Michael; Hostetler, Chris; Poole, Lamont; Holden, Carl; Rault, Didier

    2000-01-01

    Atmospheric remote sensing with the O2 A-band has a relatively long history, but most of these studies were attempting to estimate surface pressure or cloud-top pressure. Recent conceptual studies have demonstrated the potential of spaceborne high spectral resolution O2 A-band spectrometers for retrieval of aerosol and cloud optical properties. The physical rationale of this new approach is that information on the scattering properties of the atmosphere is embedded in the detailed line structure of the O2 A-band reflected radiance spectrum. The key to extracting this information is to measure the radiance spectrum at very high spectral resolution. Instrument performance requirement studies indicate that, in addition to high spectral resolution, the successful retrieval of aerosol and cloud properties from A-band radiance spectra will also require high radiometric accuracy, instrument stability, and high signal-to-noise measurements. To experimentally assess the capabilities of this promising new remote sensing application, the NASA Langley Research Center is developing an airborne high spectral resolution A-band spectrometer. The spectrometer uses a plane holographic grating with a folded Littrow geometry to achieve high spectral resolution (0.5 cm-1) and low stray light in a compact package. This instrument will be flown in a series of field campaigns beginning in 2001 to evaluate the overall feasibility of this new technique. Results from these campaigns should be particularly valuable for future spaceborne applications of A-band spectrometers for aerosol and cloud retrievals.

  13. Remote Sensing of Vegetation Species Diversity: The Utility of Integrated Airborne Hyperspectral and Lidar Data

    NASA Astrophysics Data System (ADS)

    Krause, Keith Stuart

    The change, reduction, or extinction of species is a major issue currently facing the Earth. Efforts are underway to measure, monitor, and protect habitats that contain high species diversity. Remote sensing technology shows extreme value for monitoring species diversity by mapping ecosystems and using those land cover maps or other derived data as proxies to species number and distribution. The National Ecological Observatory Network (NEON) Airborne Observation Platform (AOP) consists of remote sensing instruments such as an imaging spectrometer, a full-waveform lidar, and a high-resolution color camera. AOP collected data over the Ordway-Swisher Biological Station (OSBS) in May 2014. A majority of the OSBS site is covered by the Sandhill ecosystem, which contains a very high diversity of vegetation species and is a native habitat for several threatened fauna species. The research presented here investigates ways to analyze the AOP data to map ecosystems at the OSBS site. The research attempts to leverage the high spatial resolution data and study the variability of the data within a ground plot scale along with integrating data from the different sensors. Mathematical features are derived from the data and brought into a decision tree classification algorithm (rpart), in order to create an ecosystem map for the site. The hyperspectral and lidar features serve as proxies for chemical, functional, and structural differences in the vegetation types for each of the ecosystems. K-folds cross validation shows a training accuracy of 91%, a validation accuracy of 78%, and a 66% accuracy using independent ground validation. The results presented here represent an important contribution to utilizing integrated hyperspectral and lidar remote sensing data for ecosystem mapping, by relating the spatial variability of the data within a ground plot scale to a collection of vegetation types that make up a given ecosystem.

  14. Scanning infrared remote sensing system for identification, visualization, and quantification of airborne pollutants

    NASA Astrophysics Data System (ADS)

    Harig, Roland; Matz, Gerhard; Rusch, Peter

    2002-02-01

    Remote sensing by Fourier-transform infrared (FTIR) spectrometry allows detection, identification, and quantification of airborne pollutants. In the case of leaks in pipelines or leaks in chemical plants, chemical accidents, terrorism, or war, hazardous compounds are often released into the atmosphere. Various Fourier-transform infrared spectrometers have been developed for the remote detection and identification of hazardous clouds. However, for the localization of a leak and a complete assessment of the situation in the case of the release of a hazardous cloud, information about the position and the size of a cloud is essential. Therefore, an imaging passive remote sensing system comprised of an interferometer (Bruker OPAG 22), a data acquisition, processing, and control system with a digital signal processor (FTIR DSP), an azimuth-elevation-scanning mirror, a video system with a DSP, and a personal computer has been developed. The FTIR DSP system controls the scanning mirror, collects the interferograms, and performs the Fourier transformation. The spectra are transferred to a personal computer and analyzed by a real-time identification algorithm that does not require background spectra for the analysis. The results are visualized by a video image, overlaid by false color images. For each target compound of a spectral library, images of the coefficient of correlation, the signal to noise ratio, the brightness temperature of the background, the difference between the temperature of the ambient air and the brightness temperature of the background, and the noise equivalent column density are produced. The column densities of all directions in which a target compound has been identified may be retrieved by a nonlinear least squares fitting algorithm and an additional false color image is displayed. The system has a high selectivity, low noise equivalent spectral radiance, and it allows identification, visualization, and quantification of pollutant clouds.

  15. An Open Source Software and Web-GIS Based Platform for Airborne SAR Remote Sensing Data Management, Distribution and Sharing

    NASA Astrophysics Data System (ADS)

    Changyong, Dou; Huadong, Guo; Chunming, Han; Ming, Liu

    2014-03-01

    With more and more Earth observation data available to the community, how to manage and sharing these valuable remote sensing datasets is becoming an urgent issue to be solved. The web based Geographical Information Systems (GIS) technology provides a convenient way for the users in different locations to share and make use of the same dataset. In order to efficiently use the airborne Synthetic Aperture Radar (SAR) remote sensing data acquired in the Airborne Remote Sensing Center of the Institute of Remote Sensing and Digital Earth (RADI), Chinese Academy of Sciences (CAS), a Web-GIS based platform for airborne SAR data management, distribution and sharing was designed and developed. The major features of the system include map based navigation search interface, full resolution imagery shown overlaid the map, and all the software adopted in the platform are Open Source Software (OSS). The functions of the platform include browsing the imagery on the map navigation based interface, ordering and downloading data online, image dataset and user management, etc. At present, the system is under testing in RADI and will come to regular operation soon.

  16. Estimation of Snow Parameters Based on Passive Microwave Remote Sensing and Meteorological Information

    NASA Technical Reports Server (NTRS)

    Tsang, Leung; Hwang, Jenq-Neng

    1996-01-01

    A method to incorporate passive microwave remote sensing measurements within a spatially distributed snow hydrology model to provide estimates of the spatial distribution of Snow Water Equivalent (SWE) as a function of time is implemented. The passive microwave remote sensing measurements are at 25 km resolution. However, in mountain regions the spatial variability of SWE over a 25 km footprint is large due to topographic influences. On the other hand, the snow hydrology model has built-in topographic information and the capability to estimate SWE at a 1 km resolution. In our work, the snow hydrology SWE estimates are updated and corrected using SSM/I passive microwave remote sensing measurements. The method is applied to the Upper Rio Grande River Basin in the mountains of Colorado. The change in prediction of SWE from hydrology modeling with and without updating is compared with measurements from two SNOTEL sites in and near the basin. The results indicate that the method incorporating the remote sensing measurements into the hydrology model is able to more closely estimate the temporal evolution of the measured values of SWE as a function of time.

  17. Stereological characterization of dry alpine snow for microwave remote sensing

    NASA Technical Reports Server (NTRS)

    Davis, Robert E.; Dozier, Jeff

    1989-01-01

    A persistent problem in investigations of electromagnetic properties of snow, from reflectance at visible wavelengths to emission and backscattering in the microwave, has been the proper characterization of the snow's physical properties. It is suggested that the granular and laminar structure of snow can be measured in its aggregated state by stereology performed on sections prepared from snow specimens, and that these kinds of measurements can be incorporated into models of the electromagnetic properties. With careful sampling, anisotropy in the snow microstructure at various scales can be quantified. It is shown how stereological parameters can be averaged over orientation and optical depth for radiative transfer modeling.

  18. Spectroscopy underlying microwave remote sensing of atmospheric water vapor

    NASA Astrophysics Data System (ADS)

    Tretyakov, M. Yu.

    2016-10-01

    The paper presents a spectroscopist's view on the problem of recovery of the atmosphere humidity profile using modern microwave radiometers. Fundamental equations, including the description of their limitations, related to modeling of atmospheric water vapor absorption are given. A review of all reported to date experimental studies aimed at obtaining corresponding numerical parameters is presented. Best estimates of these parameters related to the Voigt (Lorentz, Gross, Van Vleck - Weisskopf and other equivalent) profile based modeling of the 22- and 183-GHz water vapor diagnostic lines and to non-resonance absorption as well as corresponding uncertainties are made on the basis of their comparative analysis.

  19. Advanced Microwave Precipitation Radiometer (AMPR) for remote observation of precipitation

    NASA Technical Reports Server (NTRS)

    Galliano, J. A.; Platt, R. H.

    1990-01-01

    The design, development, and tests of the Advanced Microwave Precipitation Radiometer (AMPR) operating in the 10 to 85 GHz range specifically for precipitation retrieval and mesoscale storm system studies from a high altitude aircraft platform (i.e., ER-2) are described. The primary goals of AMPR are the exploitation of the scattering signal of precipitation at frequencies near 10, 19, 37, and 85 GHz together to unambiguously retrieve precipitation and storm structure and intensity information in support of proposed and planned space sensors in geostationary and low earth orbit, as well as storm-related field experiments. The development of AMPR will have an important impact on the interpretation of microwave radiances for rain retrievals over both land and ocean for the following reasons: (1) A scanning instrument, such as AMPR, will allow the unambiguous detection and analysis of features in two dimensional space, allowing an improved interpretation of signals in terms of cloud features, and microphysical and radiative processes; (2) AMPR will offer more accurate comparisons with ground-based radar data by feature matching since the navigation of the ER-2 platform can be expected to drift 3 to 4 km per hour of flight time; and (3) AMPR will allow underflights of the SSM/I satellite instrument with enough spatial coverage at the same frequencies to make meaningful comparisons of the data for precipitation studies.

  20. Microwave remote sensing and its application to soil moisture detection

    NASA Technical Reports Server (NTRS)

    Newton, R. W. (Principal Investigator)

    1977-01-01

    The author has identified the following significant results. Experimental measurements were utilized to demonstrate a procedure for estimating soil moisture, using a passive microwave sensor. The investigation showed that 1.4 GHz and 10.6 GHz can be used to estimate the average soil moisture within two depths; however, it appeared that a frequency less than 10.6 GHz would be preferable for the surface measurement. Average soil moisture within two depths would provide information on the slope of the soil moisture gradient near the surface. Measurements showed that a uniform surface roughness similar to flat tilled fields reduced the sensitivity of the microwave emission to soil moisture changes. Assuming that the surface roughness was known, the approximate soil moisture estimation accuracy at 1.4 GHz calculated for a 25% average soil moisture and an 80% degree of confidence, was +3% and -6% for a smooth bare surface, +4% and -5% for a medium rough surface, and +5.5% and -6% for a rough surface.

  1. Developing a Scalable Remote Sampling Design for the NEON Airborne Observation Platform (AOP)

    NASA Astrophysics Data System (ADS)

    Musinsky, J.; Wasser, L. A.; Kampe, T. U.; Leisso, N.; Krause, K.; Petroy, S. B.; Cawse-Nicholson, K.; van Aardt, J. A.; Serbin, S.

    2013-12-01

    The National Ecological Observatory Network (NEON) airborne observation platform (AOP) will collect co-registered high-resolution hyperspectral imagery, discrete and waveform LiDAR, and high-resolution digital photography for more than 60 terrestrial and 23 aquatic sites spread across the continental United States, Puerto Rico, Alaska and Hawaii on an annual basis over the next 30 years. These data, to be made freely available to the public, will facilitate the scaling of field-based biological, physical and chemical measurements to regional and continental scales, enabling a better understanding of the relationships between climate variability and change, land use change and invasive species, and their ecological consequences in areas not directly sampled by the NEON facilities. However, successful up-scaling of in situ measurements requires a flight sampling design that captures environmental heterogeneity and diversity (i.e., ecological and topographic gradients), is sensitive to temporal system variation (e.g., phenology), and can respond to major disturbance events. Alignment of airborne campaigns - composed of two payloads for nominal science acquisitions and one payload for PI-driven rapid-response campaigns -- with other ground, airborne (e.g., AVIRIS) and satellite (e.g., Landsat, MODIS) collections will further facilitate scaling between sensors and data sources of varying spatial and spectral resolution and extent. This presentation will discuss the approach, challenges and future goals associated with the development of NEON AOP's sampling design, using examples from the 2013 nominal flight campaigns in the Central Plains (NEON Domain 10) and the Pacific Southwest (Domain 17), and the rapid response flight campaign of the High Park Fire site outside of Fort Collins, CO. Determination of the specific flight coverage areas for each campaign involved analysis of the landscape scale ecological, geophysical and bioclimatic attributes and trends most closely

  2. Discrimination of soil hydraulic properties by combined thermal infrared and microwave remote sensing

    NASA Technical Reports Server (NTRS)

    Vandegriend, A. A.; Oneill, P. E.

    1986-01-01

    Using the De Vries models for thermal conductivity and heat capacity, thermal inertia was determined as a function of soil moisture for 12 classes of soil types ranging from sand to clay. A coupled heat and moisture balance model was used to describe the thermal behavior of the top soil, while microwave remote sensing was used to estimate the soil moisture content of the same top soil. Soil hydraulic parameters are found to be very highly correlated with the combination of soil moisture content and thermal inertia at the same moisture content. Therefore, a remotely sensed estimate of the thermal behavior of the soil from diurnal soil temperature observations and an independent remotely sensed estimate of soil moisture content gives the possibility of estimating soil hydraulic properties by remote sensing.

  3. Active Microwave Remote Sensing Observations of Weddell Sea Ice

    NASA Technical Reports Server (NTRS)

    Drinkwater, Mark R.

    1997-01-01

    Since July 1991, the European Space Agency's ERS-1 and ERS-2 satellites have acquired radar data of the Weddell Sea, Antarctica. The Active Microwave Instrument on board ERS has two modes; SAR and Scatterometer. Two receiving stations enable direct downlink and recording of high bit-rate, high resolution SAR image data of this region. When not in an imaging mode, when direct SAR downlink is not possible, or when a receiving station is inoperable, the latter mode allows normalized radar cross-section data to be acquired. These low bit-rate ERS scatterometer data are tape recorded, downlinked and processed off-line. Recent advances in image generation from Scatterometer backscatter measurements enable complementary medium-scale resolution images to be made during periods when SAR images cannot be acquired. Together, these combined C-band microwave image data have for the first time enabled uninterrupted night and day coverage of the Weddell Sea region at both high (25 m) and medium-scale (-20 km) resolutions. C-band ERS-1 radar data are analyzed in conjunction with field data from two simultaneous field experiments in 1992. Satellite radar signature data are compared with shipborne radar data to extract a regional and seasonal signature database for recognition of ice types in the images. Performance of automated sea-ice tracking algorithms is tested on Antarctic data to evaluate their success. Examples demonstrate that both winter and summer ice can be effectively tracked. The kinematics of the main ice zones within the Weddell Sea are illustrated, together with the complementary time-dependencies in their radar signatures. Time-series of satellite images are used to illustrate the development of the Weddell Sea ice cover from its austral summer minimum (February) to its winter maximum (September). The combination of time-dependent microwave signatures and ice dynamics tracking enable various drift regimes to be defined which relate closely to the circulation of the

  4. Modeling the Effect of Vegetation on Passive Microwave Remote Sensing of Soil Moisture

    NASA Technical Reports Server (NTRS)

    Liu, Y. P.; Inguva, R.; Crosson, W. L.; Coleman, T. L.; Laymon, C.; Fahsi, A.

    1998-01-01

    The effect of vegetation on passive microwave remote sensing of soil moisture is studied. The radiative transfer modeling work of Njoku and Kong is applied to a stratified medium of which the upper layer is treated as a layer of vegetation. An effective dielectric constant for this vegetation layer is computed using estimates of the dielectric constant of individual components of the vegetation layer. The horizontally-polarized brightness temperature is then computed as a function of the incidence angle. Model predictions are used to compare with the data obtained in the Huntsville '96, remote sensing of soil moisture experiment, and with predictions obtained using a correction procedure of Jackson and Schmugge.

  5. Microwave remote sensing of Saharan ergs and Amazon vegetation

    NASA Astrophysics Data System (ADS)

    Stephen, Haroon

    This dissertation focuses on relating spaceborne microwave data to the geophysical characteristics of the Sahara desert and the Amazon vegetation. Radar and radiometric responses of the Saharan ergs are related to geophysical properties of sand formations and near surface winds. The spatial and temporal variability of the Amazon vegetation is studied using multi-frequency and multi-polarization data. The Sahara desert includes large expanses of sand dunes called ergs that are constantly reshaped by prevailing winds. Radar backscatter (sigma°) measurements observed at various incidence (theta) and azimuth (φ) angles from the NASA Scatterometer (NSCAT), the ERS scatterometer (ESCAT), the SeaWinds scatterometer aboard QuikScat (QSCAT), and the Precipitation Radar (TRMM-PR) aboard the Tropical Rain Monitoring Mission (TRMM) are used to model the sigma° response from sand dunes. Backscatter theta and φ variation depends upon the slopes and orientations of the dune slopes. Sand dunes are modeled as a composite of tilted rough facets, which are characterized by a probability distribution of tilt. The small ripples are modeled as cosinusoidal surface waves that contribute to the return signal at Bragg angles. The sigma° response is high at look angles equal to the mean tilts of the rough facets and is lower elsewhere. The modeled sigma° response is similar to NSCAT and ESCAT observations. sigma° also varies spatially and reflects the spatial inhomogeneity of the sand surface. A model incorporating the sigma° φ-modulation and spatial inhomogeneity is proposed. The maxima of the φ-modulation at theta = 33° reflect the orientation of the slip-sides on the sand surface. These slip-side orientations are consistent with the European Centre for Medium-Range Weather Forecasts wind directions spatially and temporally. Radiometric emissions from the ergs have strong dependence on the surface geometry. The radiometric temperature (Tb) of ergs is modeled as the weighted sum

  6. Remote detection and ecological monitoring of the industrial and natural nuclei activity of radioactive elements based on passive microwave radiometry

    NASA Astrophysics Data System (ADS)

    Chistyakova, Liliya K.; Chistyakov, Vyacheslav Y.; Losev, Dmitry V.; Penin, Sergei T.; Tarabrin, Yurij K.; Yakubov, Vladimir P.; Yurjev, Igor A.

    1998-12-01

    The passive remote method of microwave radiometry and its instrumental realization for express diagnostics of radioactive elements in the atmosphere have been discussed. Analysis of the microwave radiation due to ionization and dissociation of atmospheric components interacting with radioactive elements is carried out. The photochemical processes resulting in background microwave radiation power have been discussed. As an example, the results of natural experiment of detecting the atomic hydrogen radiation in the plume of emissions of nuclear cycle processing plants have been presented.

  7. Active microwave remote sensing of an anisotropic random medium layer

    NASA Technical Reports Server (NTRS)

    Lee, J. K.; Kong, J. A.

    1985-01-01

    A two-layer anisotropic random medium model has been developed to study the active remote sensing of the earth. The dyadic Green's function for a two-layer anisotropic medium is developed and used in conjunction with the first-order Born approximation to calculate the backscattering coefficients. It is shown that strong cross-polarization occurs in the single scattering process and is indispensable in the interpretation of radar measurements of sea ice at different frequencies, polarizations, and viewing angles. The effects of anisotropy on the angular responses of backscattering coefficients are also illustrated.

  8. Supporting relief efforts of the 2010 Haitian earthquake using an airborne multimodal remote sensing platform

    NASA Astrophysics Data System (ADS)

    Faulring, Jason W.; McKeown, Donald M.; van Aardt, Jan; Casterline, May V.; Bartlett, Brent D.; Raqueno, Nina

    2011-06-01

    The small island nation of Haiti was devastated in early 2010 following a massive 7.0 earthquake that brought about widespread destruction of infrastructure, many deaths and large-scale displacement of the population in the nation's major cities. The World Bank and ImageCat, Inc tasked the Rochester Institute of Technology's (RIT) Wildfire Airborne Sensor Platform (WASP) to gather a multi-spectral and multi-modal assessment of the disaster over a seven-day period to be used for relief and reconstruction efforts. Traditionally, private sector aerial remote sensing platforms work on processing and product delivery timelines measured in days, a scenario that has the potential to reduce the value of the data in time-sensitive situations such as those found in responding to a disaster. This paper will describe the methodologies and practices used by RIT to deliver an open set of products typically within a twenty-four hour period from when they were initially collected. Response to the Haiti disaster can be broken down into four major sections: 1) data collection and logistics, 2) transmission of raw data from a remote location to a central processing and dissemination location, 3) rapid image processing of a massive amount of raw data, and 4) dissemination of processed data to global organizations utilizing it to provide the maximum benefit. Each section required it's own major effort to ensure the success of the overall mission. A discussion of each section will be provided along with an analysis of methods that could be implemented in future exercises to increase efficiency and effectiveness.

  9. Optical design of high resolution and large format CCD airborne remote sensing camera on unmanned aerial vehicle

    NASA Astrophysics Data System (ADS)

    Qian, Yixian; Cheng, Xiaowei; Shao, Jie

    2010-11-01

    Unmanned aerial vehicle remote sensing (UAVRS) is lower in cost, flexible on task arrangement and automatic and intelligent in application, it has been used widely for mapping, surveillance, reconnaissance and city planning. Airborne remote sensing missions require sensors with both high resolution and large fields of view, large format CCD digital airborne imaging systems are now a reality. A refractive system was designed to meet the requirements with the help of code V software, It has a focal length of 150mm, F number of 5.6, waveband of 0.45~0.7um, and field of view reaches 20°. It is shown that the value of modulation transfer function is higher than 0.5 at 55lp/mm, distortion is less than 0.1%, image quality reaches the diffraction limit. The system with large format CCD and wide field can satisfy the demand of the wide ground overlay area and high resolution. The optical system with simpler structure, smaller size and lighter weight, can be used in airborne remote sensing.

  10. Remote detection of water stress in orchard canopies using MODIS/ASTER airborne simulator (MASTER) data

    NASA Astrophysics Data System (ADS)

    Cheng, Tao; Riaño, David; Koltunov, Alexander; Whiting, Michael L.; Ustin, Susan L.

    2011-09-01

    Vegetation canopy water content (CWC) is an important parameter for monitoring natural and agricultural ecosystems. Previous studies focused on the observation of annual or monthly variations in CWC but lacked temporal details to study vegetation physiological activities within a diurnal cycle. This study provides an evaluation of detecting vegetation diurnal water stress using airborne data acquired with the MASTER instrument. Concurrent with the morning and afternoon acquisitions of MASTER data, an extensive field campaign was conducted over almond and pistachio orchards in southern San Joaquin Valley of California to collect CWC measurements. Statistical analysis of the field measurements indicated a significant decrease of CWC from morning to afternoon. Field measured CWC was linearly correlated to the normalized difference infrared index (NDII) calculated with atmospherically corrected MASTER reflectance data using either FLAASH or empirical line (EL). Our regression analysis demonstrated that both atmospheric corrections led to a root mean square error (RMSE) of approximately 0.035 kg/m2 for the estimation of CWC (R2=0.42 for FLAASH images and R2=0.45 for EL images). Remote detection of the subtle decline in CWC awaits an improved prediction of CWC. Diurnal CWC maps revealed the spatial patterns of vegetation water status in response to variations in irrigation treatment.

  11. Assessing stream temperature variations in the Pacific Northwest using airborne thermal infrared remote sensing

    NASA Astrophysics Data System (ADS)

    Tan, J.; Cherkauer, K. A.

    2010-12-01

    Stream temperature is an important indicator of water quality, and a significant concern for endangered cold-water fish species in the Pacific Northwest. Thermal-infrared (TIR) remote sensing allows for the observation of water temperatures in entire river systems in a relatively short space of time, as opposed to more traditional point-based in situ observing methods that can capture only localized water conditions. Point measurements can therefore miss important spatial patterns associated with various factors including exposure to solar radiation, urbanization, changes to riparian zone vegetation, and the presence of groundwater returns and springs. In this paper, we analyze moderate resolution TIR imagery collected from an airborne platform for the Green River in Washington State. Five-meter MODIS/ASTER (MASTER) imagery along the main channel of the Green River was acquired in multiple straight line passes with image overlaps occurring at time intervals of between 3 and 30 minutes on August 25 and 27, 2001. Overlaps of two adjacent images provide a detailed comparison of how stream temperature changes over relatively short time scales, while image captured from different days help identify persistent localized temperature differences. Trees and shrubs in the riparian zone increases shading of the stream and reduces along-stream increases in temperature compared to stream reaches with reduced shading, such as urban areas. Longitudinal profiles of stream temperature from upstream to downstream show that other factors, such as sandbars and cold-water seeps, also contribute to along-stream temperature variations.

  12. Operational considerations for the application of remotely sensed forest data from LANDSAT or other airborne platforms

    NASA Technical Reports Server (NTRS)

    Baker, G. R.; Fethe, T. P.

    1975-01-01

    Research in the application of remotely sensed data from LANDSAT or other airborne platforms to the efficient management of a large timber based forest industry was divided into three phases: (1) establishment of a photo/ground sample correlation, (2) investigation of techniques for multi-spectral digital analysis, and (3) development of a semi-automated multi-level sampling system. To properly verify results, three distinct test areas were selected: (1) Jacksonville Mill Region, Lower Coastal Plain, Flatwoods, (2) Pensacola Mill Region, Middle Coastal Plain, and (3) Mississippi Mill Region, Middle Coastal Plain. The following conclusions were reached: (1) the probability of establishing an information base suitable for management requirements through a photo/ground double sampling procedure, alleviating the ground sampling effort, is encouraging, (2) known classification techniques must be investigated to ascertain the level of precision possible in separating the many densities involved, and (3) the multi-level approach must be related to an information system that is executable and feasible.

  13. Remote tree species identification in a diverse tropical forest using airborne imaging spectroscopy

    NASA Astrophysics Data System (ADS)

    Baldeck, C.; Asner, G. P.; Kellner, J. R.; Martin, R.; Anderson, C.; Knapp, D. E.

    2013-12-01

    Plant species identification and mapping based on remotely-sensed spectral signatures is a challenging task with the potential to contribute enormously to ecological studies. This task is especially difficult in highly diverse ecosystems such as tropical forests, and for these ecosystems it may be more strategic to direct efforts to identifying crowns of a focal species. We used imaging spectrometer data collected by the Carnegie Airborne Observatory over Barro Colorado Island, Panama, to develop classification models for the identification of tree crowns belonging to selected focal species. We explored alternative methods for detecting crowns of focal species, which included binary, one-class, and biased support vector machines (SVM). Best performance was given by binary and biased SVM, with poor performance observed for one-class SVM. Binary and biased SVM were able to identify crowns of focal species with classification sensitivity and specificity of 87-91% and 89-94%, respectively. The main tradeoff between binary and biased SVM is that construction of binary SVM requires a far greater amount of training data while biased SVM is more difficult to parameterize. Our results show that with sufficient training data, focal species can be mapped with a high degree of accuracy, in terms of both sensitivity and specificity, in this diverse tropical forest.

  14. Characterization of vegetation by microwave and optical remote sensing

    NASA Technical Reports Server (NTRS)

    Daughtry, C. S. T. (Principal Investigator); Ranson, K. J.; Biehl, L. L.

    1986-01-01

    Two series of carefully controlled experiments were conducted. First, plots of important crops (corn, soybeans, and sorghum), prairie grasses (big bluestem, switchgrass, tal fescue, orchardgrass, bromegrass), and forage legumes (alfalfa, red clover, and crown vetch) were manipulated to produce wide ranges of phytomass, leaf area index, and canopy architecture. Second, coniferous forest canopies were simulated using small balsam fir trees grown in large pots of soil and arranged systematically on a large (5 m) platform. Rotating the platform produced many new canopies for frequency and spatial averaging of the backscatter signal. In both series of experiments, backscatter of 5.0 GHz (C-Band) was measured as a function of view angle and polarization. Biophysical measurements included leaf area index, fresh and dry phytomass, water content of canopy elements, canopy height, and soil roughness and moisture content. For a subset of the above plots, additional measurements were acquired to exercise microwave backscatter models. These measurements included size and shape of leaves, stems, and fruit and the probability density function of leaf and stem angles. The relationships of the backscattering coefficients and the biophysical properties of the canopies were evaluated using statistical correlations, analysis of variance, and regression analysis. Results from the corn density and balsam fir experiments are discussed and analyses of data from the other experiments are summarized.

  15. A summary of microwave remote sensing investigations planned for BOREAS

    NASA Technical Reports Server (NTRS)

    Mcdonald, Kyle C.

    1993-01-01

    The Boreal Ecosystem - Atmosphere Study (BOREAS) is a multidisciplinary field and remote sensing study that will be implemented jointly by the United States and Canada. The goal of BOREAS is to obtain an improved understanding of the interactions between the boreal forest biome and the atmosphere in order to clarify their roles in global change. Specific objectives are to improve the understanding of the processes that govern the exchanges of water, energy, heat, carbon, and trace gases between boreal ecosystems and the atmosphere, and to develop and validate remote sensing algorithms for transferring the understanding of these processes from local to regional scales. Two principal field sites, both within Canada, were selected. The northern site is located near Thompson, Manitoba, and the southern site encompasses Prince Albert National Park in Saskatchewan. The growing season in the northern site tends to be limited by growing-degree days while the southern site is limited by soil moisture and fire frequency. Most of the field work will occur at these two sites during 1993 and 1994 as part of six field campaigns. The first of these campaigns is scheduled for August 1993 and will involve instrument installation and an operational shakedown. Three large scale Intensive Field Campaigns (IFC's) are scheduled for 1994, along with two smaller scale Focused Field Campaigns (FFC's). The first 1994 campaign will be an FFC designed to capture the biome under completely frozen conditions during the winter. The second FFC and the first IFC are scheduled to capture the spring thaw period. Another IFC will take place in the summer during a period of maximum water stress. Finally, the third FFC will be scheduled to capture the collapse into senescence during the fall.

  16. Estimation of Soil Moisture Profile using a Simple Hydrology Model and Passive Microwave Remote Sensing

    NASA Technical Reports Server (NTRS)

    Soman, Vishwas V.; Crosson, William L.; Laymon, Charles; Tsegaye, Teferi

    1998-01-01

    Soil moisture is an important component of analysis in many Earth science disciplines. Soil moisture information can be obtained either by using microwave remote sensing or by using a hydrologic model. In this study, we combined these two approaches to increase the accuracy of profile soil moisture estimation. A hydrologic model was used to analyze the errors in the estimation of soil moisture using the data collected during Huntsville '96 microwave remote sensing experiment in Huntsville, Alabama. Root mean square errors (RMSE) in soil moisture estimation increase by 22% with increase in the model input interval from 6 hr to 12 hr for the grass-covered plot. RMSEs were reduced for given model time step by 20-50% when model soil moisture estimates were updated using remotely-sensed data. This methodology has a potential to be employed in soil moisture estimation using rainfall data collected by a space-borne sensor, such as the Tropical Rainfall Measuring Mission (TRMM) satellite, if remotely-sensed data are available to update the model estimates.

  17. High Spatial Resolution Airborne Multispectral Thermal Infrared Remote Sensing Data for Analysis of Urban Landscape Characteristics

    NASA Technical Reports Server (NTRS)

    Quattrochi, Dale A.; Luvall, Jeffrey C.; Estes, Maurice G., Jr.; Arnold, James E. (Technical Monitor)

    2000-01-01

    We have used airborne multispectral thermal infrared (TIR) remote sensing data collected at a high spatial resolution (i.e., 10m) over several cities in the United States to study thermal energy characteristics of the urban landscape. These TIR data provide a unique opportunity to quantify thermal responses from discrete surfaces typical of the urban landscape and to identify both the spatial arrangement and patterns of thermal processes across the city. The information obtained from these data is critical to understanding how urban surfaces drive or force development of the Urban Heat Island (UHI) effect, which exists as a dome of elevated air temperatures that presides over cities in contrast to surrounding non-urbanized areas. The UHI is most pronounced in the summertime where urban surfaces, such as rooftops and pavement, store solar radiation throughout the day, and release this stored energy slowly after sunset creating air temperatures over the city that are in excess of 2-4'C warmer in contrast with non-urban or rural air temperatures. The UHI can also exist as a daytime phenomenon with surface temperatures in downtown areas of cities exceeding 38'C. The implications of the UHI are significant, particularly as an additive source of thermal energy input that exacerbates the overall production of ground level ozone over cities. We have used the Airborne Thermal and Land Applications Sensor (ATLAS), flown onboard a Lear 23 jet aircraft from the NASA Stennis Space Center, to acquire high spatial resolution multispectral TIR data (i.e., 6 bandwidths between 8.2-12.2 (um) over Huntsville, Alabama, Atlanta, Georgia, Baton Rouge, Louisiana, Salt Lake City, Utah, and Sacramento, California. These TIR data have been used to produce maps and other products, showing the spatial distribution of heating and cooling patterns over these cities to better understand how the morphology of the urban landscape affects development of the UHI. In turn, these data have been used

  18. Wide-Band Airborne Microwave and Millimeter-Wave Radiometers to Provide High-Resolution Wet-Tropospheric Path Delay Corrections for Coastal and Inland Water Altimetry

    NASA Astrophysics Data System (ADS)

    Reising, Steven C.; Kangaslahti, Pekka; Brown, Shannon T.; Tanner, Alan B.; Padmanabhan, Sharmila; Parashare, Chaitali; Montes, Oliver; Dawson, Douglas E.; Gaier, Todd C.; Khayatian, Behrouz; Bosch-Lluis, Xavier; Nelson, Scott P.; Johnson, Thaddeus; Hadel, Victoria; Gilliam, Kyle L.; Razavi, Behzad

    2013-04-01

    Current satellite ocean altimeters include nadir-viewing, co-located 18-34 GHz microwave radiometers to measure wet-tropospheric path delay. Due to the area of the surface instantaneous fields of view (IFOV) at these frequencies, the accuracy of wet path retrievals is substantially degraded near coastlines, and retrievals are not provided over land. Retrievals are flagged as not useful about 40 km from the world's coastlines. A viable approach to improve their capability is to add wide-band millimeter-wave window channels at 90 to 170 GHz, yielding finer spatial resolution for a fixed antenna size. In addition, NASA's Surface Water and Ocean Topography (SWOT) mission in formulation (Phase A) is planned for launch in late 2020. The primary objectives of SWOT are to characterize ocean sub-mesoscale processes on 10-km and larger scales in the global oceans, and to measure the global water storage in inland surface water bodies and the flow rate of rivers. Therefore, an important new science objective of SWOT is to transition satellite radar altimetry into the coastal zone. The addition of millimeter-wave channels near 90, 130 and 166 GHz to current Jason-class radiometers is expected to improve retrievals of wet-tropospheric delay in coastal areas and to enhance the potential for over-land retrievals. The Ocean Surface Topography Science Team Meeting recommended in 2012 to add these millimeter-wave channels to the Jason Continuity of Service (CS) mission. To reduce the risks associated with wet-tropospheric path delay correction over coastal areas and fresh water bodies, we are developing an airborne radiometer with 18.7, 23.8 and 34.0 GHz microwave channels, as well as millimeter-wave window channels at 90, 130 and 166 GHz, and temperature sounding above 118 as well as water vapor sounding below 183 GHz for validation of wet-path delay. For nadir-viewing space-borne radiometers with no moving parts, two-point internal calibration sources are necessary, and the

  19. CASI/SASI airborne hyperspectral remote sensing anomaly extraction of metallogenic prediction research in Gansu Beishan South Beach area

    NASA Astrophysics Data System (ADS)

    Che, Yongfei; Zhao, Yingjun

    2014-11-01

    Hyperspectral remote sensing has one of the technical advantages atlas. The known deposits of Gansu Beishan South Beach deposits as the study area, based on the theory of wall rock alteration, using airborne hyperspectral remote sensing data (CASI/SASI), extracted mineralization alteration information and analysis. Based on airborne hyperspectral remote sensing mineral mapping results in the study area, Combining analysising of possible mineral formation fluid properties, spatial distribution characteristics and time evolution with analysising of mineral formation environment (lithology and tectonic environment), construction of the South Beach gold deposit location model, the deposit location model as a guide, comprehensive analysis of mineralization geological background and surface geochemical data, delineated mineralization favorable areas. The field investigation showed that signs of altered development of strong in the delineation of the mineralization favorable areas and metallogenic potential of better, is worth paying attention to the prospecting target area. Further explanation that the hyperspectral remote sensing can provide accurate and reliable information for the prospecting, and is worthy of further mining the ore prospecting potential.

  20. Microwave Interferometric Radiometry in Remote Sensing: an Invited Historical Review

    NASA Technical Reports Server (NTRS)

    Martin-Neira, M.; LeVine, D. M.; Kerr, Y.; Skou, N.; Peichl, M.; Camps, A.; Corbella, I.; Hallikainen, M.; Font, J.; Wu, J.; Mecklenburg, S.; Drusch, M.

    2014-01-01

    The launch of the Soil Moisture and Ocean Salinity (SMOS) mission on 2 November 2009 marked a milestone in remote sensing for it was the first time a radiometer capable of acquiring wide field of view images at every single snapshot, a unique feature of the synthetic aperture technique, made it to space. The technology behind such an achievement was developed, thanks to the effort of a community of researchers and engineers in different groups around the world. It was only because of their joint work that SMOS finally became a reality. The fact that the European Space Agency, together with CNES (Centre National d'Etudes Spatiales) and CDTI (Centro para el Desarrollo Tecnológico e Industrial), managed to get the project through should be considered a merit and a reward for that entire community. This paper is an invited historical review that, within a very limited number of pages, tries to provide insight into some of the developments which, one way or another, are imprinted in the name of SMOS.

  1. Microwave interferometric radiometry in remote sensing: An invited historical review

    NASA Astrophysics Data System (ADS)

    Martín-Neira, M.; LeVine, D. M.; Kerr, Y.; Skou, N.; Peichl, M.; Camps, A.; Corbella, I.; Hallikainen, M.; Font, J.; Wu, J.; Mecklenburg, S.; Drusch, M.

    2014-06-01

    The launch of the Soil Moisture and Ocean Salinity (SMOS) mission on 2 November 2009 marked a milestone in remote sensing for it was the first time a radiometer capable of acquiring wide field of view images at every single snapshot, a unique feature of the synthetic aperture technique, made it to space. The technology behind such an achievement was developed, thanks to the effort of a community of researchers and engineers in different groups around the world. It was only because of their joint work that SMOS finally became a reality. The fact that the European Space Agency, together with CNES (Centre National d'Etudes Spatiales) and CDTI (Centro para el Desarrollo Tecnológico e Industrial), managed to get the project through should be considered a merit and a reward for that entire community. This paper is an invited historical review that, within a very limited number of pages, tries to provide insight into some of the developments which, one way or another, are imprinted in the name of SMOS.

  2. Remote Sensing of Ocean Currents Using a Multifrequency Microwave Radar

    NASA Astrophysics Data System (ADS)

    Popstefanija, Ivan P.

    A remote sensing system for measuring ocean surface currents is presented in this thesis. Included are a review of the Stepped Frequency Delta K (SFDK) radar system hardware, a description of the system performance, experimental results of ocean current measurements, and comparisons of the measurements with a conventional current probe and a wind driven current model. Important features of this radar system are (1) its capability to perform real time processing of the collected data and (2) its frequency agility, which provides significant improvement of the system's signal-to-clutter ratio. The real time processing capabilities were essential to the collection and monitoring of the ocean currents for long periods of time that is necessary to understand and interpret the results. The SFDK radar participated in two month long experiments. During the first experiment at N. Truro, MA, the SFDK radar demonstrated its ability to make precise phase velocity measurements over long periods of time. During the second experiment on the Chesapeake Light Tower, the radar was able to sense both tidal and wind driven current components. Comparison of radar data and in situ measurements during the CLT experiment shows that the instrument possesses a unique capability to measure near surface currents--not possible with in situ probes.

  3. Sea surface signature of tropical cyclones using microwave remote sensing

    NASA Astrophysics Data System (ADS)

    Kil, Bumjun; Burrage, Derek; Wesson, Joel; Howden, Stephan

    2013-06-01

    Measuring the sea surface during tropical cyclones (TC) is challenging due to severe weather conditions that prevent shipboard measurements and clouds which mask the sea surface for visible satellite sensors. However, sea surface emission in the microwave L-band can penetrate rain and clouds and be measured from space. The European Space Agency (ESA) MIRAS L-band radiometer on the Soil Moisture and Ocean Salinity (SMOS) satellite enables a view of the sea surface from which the effects of tropical cyclones on sea surface emissivity can be measured. The emissivity at these frequencies is a function of sea surface salinity (SSS), sea surface temperature (SST), sea surface roughness, polarization, and angle of emission. If the latter four variables can be estimated, then models of the sea surface emissivity can be used to invert SSS from measured brightness temperature (TB). Actual measured TB from space also has affects due to the ionosphere and troposphere, which have to be compensated for, and components due to the galactic and cosmic background radiation those have to be removed. In this research, we study the relationships between retrieved SSS from MIRAS, and SST and precipitation collected by the NASA TMI sensor from the Tropical Rainfall Measuring Mission (TRMM) satellite during Hurricane Isaac, in August 2012. During the slower movement of the storm, just before landfall on the vicinity of the Louisiana Shelf, higher precipitation amounts were associated with lower SSS and slightly increased SST. This increased trend of SST and lower SSS under regions of high precipitation are indicative of inhibited vertical mixing. The SMOS Level 2 SSS were filtered by a stepwise process with removal of high uncertainty in TB under conditions of strong surface roughness which are known to create noise. The signature of increased SST associated with increasing precipitation was associated with decreased SSS during the storm. Although further research is required, this study

  4. Watershed Airborne Telemetry Experimental Research (WATER): An Remote Sensing Experiment in a Typical Arid Region Inland River Basin of China

    NASA Astrophysics Data System (ADS)

    Li, X.; Wang, J.; Ma, M.; Liu, Q.; Hu, Z.; Liu, Q.; Che, T.; Su, P.; Jin, R.; Wang, W.

    2007-12-01

    Among the many land surface experiments have been carried out so far, arid and cold regions were paid little attentions. The land surface observations in arid and cold regions, both remotely sensed and in situ, need to be strengthened for a better understanding of hydrological and ecological processes at different scales. The Watershed Airborne Telemetry Experimental Research (WATER) is a simultaneous air-borne, satellite- borne, and ground-based remote sensing experiment conducted in the Heihe Basin, the second largest inland river basin in the northwest arid regions of China. The WATER is aiming at the research on water cycles, eco- hydrological and other land surface processes in catchment-scale. Data sets with high-resolution and spatiotemporal consistency will be generated based on this experiment. An integrated watershed model and a catchment-scale land/hydrological data assimilation system is proposed to be developed. The mission of WATER is to improve the observability, understanding, and predictability of hydrological and related ecological processes at catchmental scale, accumulate basic data for the development of watershed science and promote the applicability of quantitative remote sensing in watershed science studies. The objectives of the experiment will be (1) Observing major components of water cycle in three experiment areas, i.e., cold region, forest, and arid region hydrology experiment areas, by carrying out a simultaneous air-borne, satellite-borne, and ground-based experiment. (2) Developing the scaling method using airborne high-resolution remote sensing data and intensive in situ observations, and improving remote sensing retrieval models and algorithms of water cycle variables and corresponding ecological and other land variables/parameters. (3) Developing a catchment-scale land data assimilation system, which is capable of merging multi-source and multi-scale remote sensing data to generate high resolution and spatiotemporal consistent

  5. Use of airborne remote sensing to detect riverside Brassica rapa to aid in risk assessment of transgenic crops

    NASA Astrophysics Data System (ADS)

    Elliott, Luisa M.; Mason, David C.; Allainguillaume, Joel; Wilkinson, Mike J.

    2009-11-01

    High resolution descriptions of plant distribution have utility for many ecological applications but are especially useful for predictive modeling of gene flow from transgenic crops. Difficulty lies in the extrapolation errors that occur when limited ground survey data are scaled up to the landscape or national level. This problem is epitomized by the wide confidence limits generated in a previous attempt to describe the national abundance of riverside Brassica rapa (a wild relative of cultivated rapeseed) across the United Kingdom. Here, we assess the value of airborne remote sensing to locate B. rapa over large areas and so reduce the need for extrapolation. We describe results from flights over the river Nene in England acquired using Airborne Thematic Mapper (ATM) and Compact Airborne Spectrographic Imager (CASI) imagery, together with ground truth data. It proved possible to detect 97% of flowering B. rapa on the basis of spectral profiles. This included all stands of plants that occupied >2m square (>5 plants), which were detected using single-pixel classification. It also included very small populations (<5 flowering plants, 1-2m square) that generated mixed pixels, which were detected using spectral unmixing. The high detection accuracy for flowering B. rapa was coupled with a rather large false positive rate (43%). The latter could be reduced by using the image detections to target fieldwork to confirm species identity, or by acquiring additional remote sensing data such as laser altimetry or multitemporal imagery.

  6. Vineyard zonal management for grape quality assessment by combining airborne remote sensed imagery and soil sensors

    NASA Astrophysics Data System (ADS)

    Bonilla, I.; Martínez De Toda, F.; Martínez-Casasnovas, J. A.

    2014-10-01

    Vineyard variability within the fields is well known by grape growers, producing different plant responses and fruit characteristics. Many technologies have been developed in last recent decades in order to assess this spatial variability, including remote sensing and soil sensors. In this paper we study the possibility of creating a stable classification system that better provides useful information for the grower, especially in terms of grape batch quality sorting. The work was carried out during 4 years in a rain-fed Tempranillo vineyard located in Rioja (Spain). NDVI was extracted from airborne imagery, and soil conductivity (EC) data was acquired by an EM38 sensor. Fifty-four vines were sampled at véraison for vegetative parameters and before harvest for yield and grape analysis. An Isocluster unsupervised classification in two classes was performed in 5 different ways, combining NDVI maps individually, collectively and combined with EC. The target vines were assigned in different zones depending on the clustering combination. Analysis of variance was performed in order to verify the ability of the combinations to provide the most accurate information. All combinations showed a similar behaviour concerning vegetative parameters. Yield parameters classify better by the EC-based clustering, whilst maturity grape parameters seemed to give more accuracy by combining all NDVIs and EC. Quality grape parameters (anthocyanins and phenolics), presented similar results for all combinations except for the NDVI map of the individual year, where the results were poorer. This results reveal that stable parameters (EC or/and NDVI all-together) clustering outcomes in better information for a vineyard zonal management strategy.

  7. Using High-Resolution Airborne Remote Sensing to Study Aerosol Near Clouds

    NASA Technical Reports Server (NTRS)

    Levy, Robert; Munchak, Leigh; Mattoo, Shana; Marshak, Alexander; Wilcox, Eric; Gao, Lan; Yorks, John; Platnick, Steven

    2016-01-01

    The horizontal space in between clear and cloudy air is very complex. This so-called twilight zone includes activated aerosols that are not quite clouds, thin cloud fragments that are not easily observable, and dying clouds that have not quite disappeared. This is a huge challenge for satellite remote sensing, specifically for retrieval of aerosol properties. Identifying what is cloud versus what is not cloud is critically important for attributing radiative effects and forcings to aerosols. At the same time, the radiative interactions between clouds and the surrounding media (molecules, surface and aerosols themselves) will contaminate retrieval of aerosol properties, even in clear skies. Most studies on aerosol cloud interactions are relevant to moderate resolution imagery (e.g. 500 m) from sensors such as MODIS. Since standard aerosol retrieval algorithms tend to keep a distance (e.g. 1 km) from the nearest detected cloud, it is impossible to evaluate what happens closer to the cloud. During Studies of Emissions, Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys (SEAC4RS), the NASA ER-2 flew with the enhanced MODIS Airborne Simulator (eMAS), providing MODIS-like spectral observations at high (50 m) spatial resolution. We have applied MODIS-like aerosol retrieval for the eMAS data, providing new detail to characterization of aerosol near clouds. Interpretation and evaluation of these eMAS aerosol retrievals is aided by independent MODIS-like cloud retrievals, as well as profiles from the co-flying Cloud Physics Lidar (CPL). Understanding aerosolcloud retrieval at high resolution will lead to better characterization and interpretation of long-term, global products from lower resolution (e.g.MODIS) satellite retrievals.

  8. Icepod: A modular approach to the development of an airborne remote sensing and data acquisition platform

    NASA Astrophysics Data System (ADS)

    Frearson, N.; Bell, R. E.; Tinto, K. J.; Zappa, C. J.

    2013-12-01

    The New York Air National Guard [NYANG] provides regular airborne support to the National Science Foundation [NSF] moving science parties and their equipment onto and around the ice-sheets in both polar regions during the respective summer seasons. Icepod has been developed to utilize this readily available resource, providing the aircraft with a modular external pod attached to the rear-paratrooper door on either side of the NYANG's ski-equipped LC-130s. The pod is divided into five separate bays each approximately a 2ft cube within which can be mounted an array of remote sensors. Power, heating, sensor control and data management services are provided to each bay. An Ethernet network is used to transfer commands and data packets between the individual sensors and data acquisition system located inside the aircraft. Data for each sensor is stored on ruggedized and removable hard-drives that can be taken off the aircraft at the end of a flight for further analysis. In its current configuration the pod is equipped for the remote sensing of ice sheets and their margins and the bay's contain two radar systems, radar antennas, a vibration isolated optics bay including a scanning laser, Infra-red camera and high-definition visible wave camera. Sensor data is geo-referenced using GNSS and orientation sensors located inside the pod. A Pyrometer provides the downward looking IR Camera with the current sky temperature. In January 2013, the Icepod system was flight certified at the Stratton air base in Schenectady, New York. The system deployed to Greenland in April and July 2013 to test the instrumentation suite over ice and its ease of deployment with the NYANG. Icepod can be operated in two modes, a traditional dedicated science flight mode and a piggy-back mode. In piggy-back mode science parties and their cargo are delivered to their destinations with Icepod installed but stowed. Once they have been delivered the Icepod is deployed and measurements can be taken on the

  9. Annual Snow Assessments Using Multi-spectral and Passive Microwave Remote Sensing

    NASA Astrophysics Data System (ADS)

    Daly, S. F.; Vuyovich, C. M.; Deeb, E. J.; Newman, S. D.; Baldwin, T. B.

    2010-12-01

    Since the winter season of 2004-2005, annual snow assessments have been conducted for regions across the Middle East (including Eastern Turkey, Afghanistan, and Pakistan) using multispectral (AVHRR and MODIS) and passive microwave (SSM/I and AMSR-E) remote sensing technologies. Due to limited ground-based observations of precipitation and snow pack conditions, remote sensing provides a unique opportunity to assess these conditions at different scales and offer an appraisal of the current conditions in an historical context. During each winter season, bi-weekly snow products and assessments are produced including: current Snow Covered Area (SCA) at regional and watershed scales; estimation of SCA by elevation band; current snowpack total Snow Water Equivalent (SWE) for each watershed with an historical perspective (1987-present); snow condition outlook by watershed; general summary of snow conditions based on remote sensing products and limited ground-based observations; and if warranted, a snow melt flooding advisory. Most recently, the winter 2009-2010 season provided interesting aspects that are further investigated: comparison of reported drought conditions, SCA extents, and passive microwave SWE estimates in Afghanistan; flooding event in Northeastern Afghanistan perhaps due to late season snow fall and subsequent snow melt; lower SCA in Eastern Turkey throughout winter despite heavy precipitation perhaps explained by warmer regional temperatures.

  10. Airborne Sunphotometer Studies of Aerosol Properties and Effects, Including Closure Among Satellite, Suborbital Remote, and In situ Measurements

    NASA Technical Reports Server (NTRS)

    Russlee, Philip B.; Schmid, B.; Redemann, J.; Livingston, J. M.; Bergstrom, R. W.; Ramirez, S. A.; Hipskind, R. Stephen (Technical Monitor)

    2001-01-01

    Airborne sunphotometry has been used to measure aerosols from North America, Europe, and Africa in coordination with satellite and in situ measurements in TARFOX (1996), ACE-2 (1997), PRIDE (2000), and SAFARI 2000. Similar coordinated measurements of Asian aerosols are being conducted this spring in ACE-Asia and are planned for North American aerosols this summer in CLAMS. This paper summarizes the approaches used, key results, and implications for aerosol properties and effects, such as single scattering albedo and regional radiative forcing. The approaches exploit the three-dimensional mobility of airborne sunphotometry to access satellite scenes over diverse surfaces (including open ocean with and without sunglint) and to match exactly the atmospheric layers sampled by airborne in situ measurements and other radiometers. These measurements permit tests of the consistency, or closure, among such diverse measurements as aerosol size-resolved chemical composition; number or mass concentration; light extinction, absorption, and scattering (total, hemispheric back and 180 deg.); and radiative fluxes. In this way the airborne sunphotometer measurements provide a key link between satellite and in situ measurements that helps to understand any discrepancies that are found. These comparisons have led to several characteristic results. Typically these include: (1) Better agreement among different types of remote measurements than between remote and in situ measurements. (2) More extinction derived from transmission measurements than from in situ measurements. (3) Larger aerosol absorption inferred from flux radiometry than from in situ measurements. Aerosol intensive properties derived from these closure studies have been combined with satellite-retrieved fields of optical depth to produce fields of regional radiative forcing. We show results for the North Atlantic derived from AVHRR optical depths and aerosol intensive properties from TARFOX and ACE-2. Companion papers

  11. Using Multi-Dimensional Microwave Remote Sensing Information for the Retrieval of Soil Surface Roughness

    NASA Astrophysics Data System (ADS)

    Marzahn, P.; Ludwig, R.

    2016-06-01

    In this Paper the potential of multi parametric polarimetric SAR (PolSAR) data for soil surface roughness estimation is investigated and its potential for hydrological modeling is evaluated. The study utilizes microwave backscatter collected from the Demmin testsite in the North-East Germany during AgriSAR 2006 campaign using fully polarimetric L-Band airborne SAR data. For ground truthing extensive soil surface roughness in addition to various other soil physical properties measurements were carried out using photogrammetric image matching techniques. The correlation between ground truth roughness indices and three well established polarimetric roughness estimators showed only good results for Re[ρRRLL] and the RMS Height s. Results in form of multitemporal roughness maps showed only satisfying results due to the fact that the presence and development of particular plants affected the derivation. However roughness derivation for bare soil surfaces showed promising results.

  12. COMET: a planned airborne mission to simultaneously measure CO2 and CH4 columns using airborne remote sensing and in-situ techniques

    NASA Astrophysics Data System (ADS)

    Fix, A.; Amediek, A.; Büdenbender, C.; Ehret, G.; Wirth, M.; Quatrevalet, M.; Rapp, M.; Gerilowski, K.; Bovensmann, H.; Gerbig, C.; Pfeilsticker, K.; Zöger, M.; Giez, A.

    2013-12-01

    To better predict future trends in the cycles of the most important anthropogenic greenhouse gases, CO2 and CH4, there is a need to measure and understand their distribution and variation on various scales. To address these requirements it is envisaged to deploy a suite of state-of-the-art airborne instruments that will be capable to simultaneously measure the column averaged dry-air mixing ratios (XGHG) of both greenhouse gases along the flight path. As the measurement platform serves the research aircraft HALO, a modified Gulfstream G550, operated by DLR. This activity is dubbed CoMet (CO2 and Methane Mission). The instrument package of CoMet will consist of active and passive remote sensors as well as in-situ instruments to complement the column measurements by highly-resolved profile information. As an active remote sensing instrument CHARM-F, the integrated-path differential absorption lidar currently under development at DLR, will provide both, XCO2 and XCH4, below flight altitude. The lidar instrument will be complemented by MAMAP which is a NIR/SWIR absorption spectrometer developed by University of Bremen and which is also capable to derive XCH4 and XCO2. As an additional passive instrument, mini-DOAS operated by University of Heidelberg will contribute with additional context information about the investigated air masses. In order to compare the remote sensing instruments with integrated profile information, in-situ instrumentation is indispensable. The in-situ package will therefore comprise wavelength-scanned Cavity-Ring-Down Spectroscopy (CRDS) for the detection of CO2, CH4, CO and H2O and a flask sampler for collection of atmospheric samples and subsequent laboratory analysis. Furthermore, the BAsic HALO Measurement And Sensor System (BAHAMAS) will provide an accurate set of meteorological and aircraft state parameters for each scientific flight. Within the frame of the first CoMet mission scheduled for the 2015 timeframe it is planned to concentrate

  13. Remote sensing of land scenarios with an airborne 94-GHz synthetic aperture radar

    NASA Astrophysics Data System (ADS)

    Essen, Helmut; Makaruschka, R.; Baars, E. Peter

    1996-06-01

    The scattering process of electromagnetic waves is dominated by the match between wavelength and the geometric dimensions of surface structures. With respect to the microwave radar bands millimeter-waves are better matched to small surface features of terrain. Therefore this frequency band is able to gain additional information on the terrain of interest. For high resolution imaging SAR is the favorite solution also for millimeter-wave frequencies. Compared to more classical radar bands millimeter-waves offer advantages in the SAR processing, because due to the higher primary resolution at a given antenna aperture sources of image distortions such as range migration or depth of focus can be neglected at these frequencies. Moreover the inherently short aperture time for a given resolution improves the relation to the time constant of flight instabilities and makes motion compensation a simple process. A coherent, polarimetric, high range resolution radar, operating at a nominal frequency of 94 GHz, has been installed onboard an aircraft to allow remote sensing measurements in a side looking synthetic aperture approach. The radar-raw-data were registered together with time code and inertial data of the aircraft and later on evaluated by an off-line SAR-processor. The resulting images then had to undergo an automatic recognition process to extract certain complex targets using a knowledge based production system. The paper describes the measurement system and discusses the evaluation procedures with emphasis on the applied SAR algorithm. Examples of radar images at 94 GHz are shown and samples of pattern recognition derived from the SAR images are shown.

  14. Inversion algorithms for the microwave remote sensing of soil moisture. Experiments with swept frequency microwaves

    NASA Technical Reports Server (NTRS)

    Hancock, G. D.; Waite, W. P.

    1984-01-01

    Two experiments were performed employing swept frequency microwaves for the purpose of investigating the reflectivity from soil volumes containing both discontinuous and continuous changes in subsurface soil moisture content. Discontinuous moisture profiles were artificially created in the laboratory while continuous moisture profiles were induced into the soil of test plots by the environment of an agricultural field. The reflectivity for both the laboratory and field experiments was measured using bi-static reflectometers operated over the frequency ranges of 1.0 to 2.0 GHz and 4.0 to 8.0 GHz. Reflectivity models that considered the discontinuous and continuous moisture profiles within the soil volume were developed and compared with the results of the experiments. This comparison shows good agreement between the smooth surface models and the measurements. In particular the comparison of the smooth surface multi-layer model for continuous moisture profiles and the yield experiment measurements points out the sensitivity of the specular component of the scattered electromagnetic energy to the movement of moisture in the soil.

  15. Correlating rainfall with remotely sensed microwave radiation using physically based models

    NASA Technical Reports Server (NTRS)

    Camillo, P. J.; Schmugge, T. J.

    1984-01-01

    This simulation study evaluates the response of a 21-cm radiometer, measuring the radiation emitted by a bare soil, to varying accumulations of rain. It is shown that correlations between the decrease in emissivity after a rain storm and the total accumulation depend strongly on the physical characteristics of the soil which affect its capacity to hold water. These are primarily soil texture and pre-rain soil moisture. A method is also discussed which would use the numerical models with remotely sensed microwave brightness and surface physical temperatures, along with conventional weather data, to estimate the total accumulation.

  16. Allometric Relationships in Soybean to Estimate the Effect of Vegetation on Microwave Remote Sensing

    NASA Astrophysics Data System (ADS)

    Spencer, A. J.; Hornbuckle, B. K.; Patton, J.

    2011-12-01

    Microwave remote sensing is capable of developing soil moisture maps through satellite data. The resulting maps are useful indicators of hydrologic conditions. Water concentrations are deterministic of flooding events and potential agricultural resources. The emitted microwave radiation of soil is influenced by its moisture content. Models have been developed to incorporate parameters besides soil moisture that affect the emitted microwave radiation. We are interested in one of these parameters known as the optical depth. Optical depth is the effect of the canopy on the observed emission of microwaves. The vegetation directly competes with soil moisture as a contributor to the emitted microwave radiation and the optical depth appears within every term in the present satellite retrieval algorithm. Optical depth has been shown to be directly proportional to the amount of water contained within vegetation tissue. Allometry is a way to effectively and efficiently measure vegetation water content through the way the parts of the organism change in proportion to each other in response to growth. Vegetation water content is difficult to measure without taking destructive measurements, in addition to involving too much time and manual labor. Therefore, another component of vegetation can be measured in relation to vegetation water content which can then be related to optical depth. In our study we worked in soybean, a major crop in many areas of the world. We compared soybean vegetation water content to an estimate of the volume of an individual plant expressed as the product of canopy height and stem diameter squared (Zc*Sd2), both of which can be measured easily and nondestructively. We also wished to determine whether vegetation water content remained constant as a percentage to total biomass over the length of the growing season. Agricultural yield is most likely a function of the total dry mass of vegetation. Establishing the relationship between vegetation water

  17. The science benefits of and the antenna requirements for microwave remote sensing from geostationary orbit

    NASA Technical Reports Server (NTRS)

    Stutzman, Warren L. (Editor); Brown, Gary S. (Editor)

    1991-01-01

    The primary objective of the Large Space Antenna (LSA) Science Panel was to evaluate the science benefits that can be realized with a 25-meter class antenna in a microwave/millimeter wave remote sensing system in geostationary orbit. The panel concluded that a 25-meter or larger antenna in geostationary orbit can serve significant passive remote sensing needs in the 10 to 60 GHz frequency range, including measurements of precipitation, water vapor, atmospheric temperature profile, ocean surface wind speed, oceanic cloud liquid water content, and snow cover. In addition, cloud base height, atmospheric wind profile, and ocean currents can potentially be measured using active sensors with the 25-meter antenna. Other environmental parameters, particularly those that do not require high temporal resolution, are better served by low Earth orbit based sensors.

  18. Procedures for the description of agricultural crops and soils in optical and microwave remote sensing studies

    NASA Technical Reports Server (NTRS)

    Cihlar, J.; Dobson, M. C.; Schmugge, T.; Hoogeboom, P.; Janse, A. R. P.

    1987-01-01

    This paper describes procedures for characterizing agricultural crops and soils in remote sensing studies. The procedures are based on the accumulated experience of a number of researchers active in this field. Therefore, they represent a compromise between the theoretically desirable and the practically feasible, and should thus be an effective aid in further studies of this type. Although the guidelines were prepared specifically for microwave studies, adjustments were made to render the procedures applicable to optical studies as well. Given the increasing number of research teams involved in remote sensing applied to agriculture, there is an opportunity to acquire a broad data base on soils and crops in various geographic regions. To allow intercomparisons of such data, they must be obtained in a consistent manner. By following the proposed procedures and reporting results using the parameters described here, such intercomparisons should be possible on a continental or a global scale.

  19. Formation of MOS gates by rapid thermal/microwave remote plasma multiprocessing

    NASA Astrophysics Data System (ADS)

    Moslehi, Mehrdad M.; Saraswat, Krishna C.

    A novel cold wall single wafer lamp heated Rapid Thermal/Microwave Remote Plasma Multiprocessing (RTMRPM) reactor has been developed for multilayer in-situ growth and deposition of dielectrics, silicon, and metals. This equipment is the result of an attempt to enhance semiconductor processing equipment versatility, to improve process reproducibility and uniformity, to increase growth and deposition rates at reduced processing temperatures, and to achieve in situ multiprocessing in conjunction with real time process monitoring and automation. For high performance MOS VLSI applications, a variety of selective and nonselective tungsten deposition processes were investigated in this work. The tungsten gate MOS devices fabricated using the remote plasma multiprocessing techniques exhibited negligible plasma damage and near ideal electrical characteristics. The flexibility of the reactor allows optimization of each process step yet allows multiprocessing.

  20. Passive microwave remote sensing of an anisotropic random-medium layer

    NASA Technical Reports Server (NTRS)

    Lee, J. K.; Kong, J. A.

    1985-01-01

    The principle of reciprocity is invoked to calculate the brightness temperatures for passive microwave remote sensing of a two-layer anisotropic random medium. The bistatic scattering coefficients are first computed with the Born approximation and then integrated over the upper hemisphere to be subtracted from unity, in order to obtain the emissivity for the random-medium layer. The theoretical results are illustrated by plotting the emissivities as functions of viewing angles and polarizations. They are used to interpret remote sgnsing data obtained from vegetation canopy where the anisotropic random-medium model applies. Field measurements with corn stalks arranged in various configurations with preferred azimuthal directions are successfully interpreted with this model.

  1. Ground registration of data from an airborne Multifrequency Microwave Radiometer (MfMR). [Colby, Kansas

    NASA Technical Reports Server (NTRS)

    Richter, J. C. (Principal Investigator)

    1981-01-01

    The agricultural soil moisture experiment was conducted near Colby, Kansas, in July and August 1978. A portion of the data collected was taken with a five band microwave radiometer. A method of locating the radiometer footprints with respect to a ground based coordinate system is documented. The procedure requires that the airplane's flight parameters along with aerial photography be acquired simultaneously with the radiometer data. The software which documented reads in data from the precision radiation thermometer (PRT Model 5) and attaches the scene temperature to the corresponding multifrequency microwave radiometer data. Listings of the programs used in the registration process are included.

  2. Synergies of the European Microwave Remote Sensing Missions SMOS and ASCAT for Monitoring Soil Moisture

    NASA Astrophysics Data System (ADS)

    Scipal, K.; Wagner, W.

    2003-04-01

    The lack of global soil moisture observations is one of the most glaring and pressing deficiencies in current research activities of related fields, from climate monitoring and ecological applications to the quantification of biogeophysical fluxes. This has implications for important issues of the international political agenda like managing global water resources, securing food production and studying climate change. Currently it is held that only microwave remote sensing offers the potential to produce reliable global scale soil moisture information economically. Recognising the urgent need for a soil moisture mission several international initiatives are planning satellite missions dedicated to monitor the global hydrological cycle among them two European microwave satellites. ESA is planning to launch the Soil Moisture and Ocean Salinity Mission SMOS, in 2006. SMOS will measure soil moisture over land and ocean salinity over the oceans. The mission rests on a passive microwave sensor (radiometer) operated in L-band which is currently believed to hold the largest potential for soil moisture retrieval. One year before (2005) EUMETSAT will launch the Meteorological Operational satellite METOP which carries the active microwave system Advanced Scatterometer ASCAT on board. ASCAT has been designed to retrieve winds over the oceans but recent research has established its capability to retrieve soil moisture. Although currently it is hold that, using active microwave techniques, the effect of surface roughness dominates that of soil moisture (while the converse is true for radiometers), the ERS scatterometer was successfully used to derive global soil moisture information at a spatial resolution of 50 km with weekly to decadal temporal resolution. The quality of the soil moisture products have been assessed by independent experts in several pilot projects funded by the European Space Agency. There is evidence to believe that both missions will provide a flow of

  3. Effects of the Ionosphere on Passive Microwave Remote Sensing of Ocean Salinity from Space

    NASA Technical Reports Server (NTRS)

    LeVine, D. M.; Abaham, Saji; Hildebrand, Peter H. (Technical Monitor)

    2001-01-01

    Among the remote sensing applications currently being considered from space is the measurement of sea surface salinity. The salinity of the open ocean is important for understanding ocean circulation and for modeling energy exchange with the atmosphere. Passive microwave remote sensors operating near 1.4 GHz (L-band) could provide data needed to fill the gap in current coverage and to complement in situ arrays being planned to provide subsurface profiles in the future. However, the dynamic range of the salinity signal in the open ocean is relatively small and propagation effects along the path from surface to sensor must be taken into account. In particular, Faraday rotation and even attenuation/emission in the ionosphere can be important sources of error. The purpose or this work is to estimate the magnitude of these effects in the context of a future remote sensing system in space to measure salinity in L-band. Data will be presented as a function of time location and solar activity using IRI-95 to model the ionosphere. The ionosphere presents two potential sources of error for the measurement of salinity: Rotation of the polarization vector (Faraday rotation) and attenuation/emission. Estimates of the effect of these two phenomena on passive remote sensing over the oceans at L-band (1.4 GHz) are presented.

  4. Research on estimation crop planting area by integrating the optical and microwave remote sensing data

    NASA Astrophysics Data System (ADS)

    Liu, Jiang; Yu, Fan; Liu, Dandan; Tian, Jing; Zhang, Weicheng; Wang, Qiang; Yang, Jinling; Zhang, Lei

    2015-12-01

    Considering the problem in monitoring agricultural condition in the semi-arid areas of Northwest of China, we propose a new method for estimation of crop planting area, using the single phase optical and microwave remote sensing data collaboratively, which have demonstrated their respective advantages in the extraction of surface features. In the model, the ASAR backscatter coefficient is normalized by the incident angle at first, then the classifier based on Bayesian network is developed, and the VV, VH polarization of ASAR and all the 7 TM bands are taken as the input of the classifier to get the class labels of each pixel of the images. Moreover the crop planting areas can be extracted by the classification results. At last, the model is validated for the necessities of normalization by the incident angle and integration of TM and ASAR respectively. It results that the estimation accuracy of crop planting area of corn and other crops garden are 98.47% and 78.25% respectively using the proposed method, with an improvement of estimation accuracy of about 3.28% and 4.18% relative to single TM classification. These illustrate that synthesis of optical and microwave remote sensing data is efficient and potential in estimation crop planting area.

  5. Microwave remote plasma enhanced-atomic layer deposition system with multicusp confinement chamber

    SciTech Connect

    Dechana, A.; Thamboon, P.; Boonyawan, D.

    2014-10-15

    A microwave remote Plasma Enhanced-Atomic Layer Deposition system with multicusp confinement chamber is established at the Plasma and Beam Physics research facilities, Chiang Mai, Thailand. The system produces highly-reactive plasma species in order to enhance the deposition process of thin films. The addition of the multicusp magnetic fields further improves the plasma density and uniformity in the reaction chamber. Thus, the system is more favorable to temperature-sensitive substrates when heating becomes unwanted. Furthermore, the remote-plasma feature, which is generated via microwave power source, offers tunability of the plasma properties separately from the process. As a result, the system provides high flexibility in choice of materials and design experiments, particularly for low-temperature applications. Performance evaluations of the system were carried on coating experiments of Al{sub 2}O{sub 3} layers onto a silicon wafer. The plasma characteristics in the chamber will be described. The resulted Al{sub 2}O{sub 3} films—analyzed by Rutherford Backscattering Spectrometry in channeling mode and by X-ray Photoelectron Spectroscopy techniques—will be discussed.

  6. Remote Sounding of Cloud Parameters from a Combination of Infrared and Microwave Channels.

    NASA Astrophysics Data System (ADS)

    Yeh, Hwa-Young; Liou, Kuo-Nan

    1983-02-01

    This study explores the utilization of both infrared and microwave sounding channels for the inference of the high and low cloud parameters. The necessary parameterized equations for infrared and microwave radiative transfer have been derived for applications to remote sensing from satellites. Retrieval programs have been developed for the determination of the high cloud top height, high cloud thickness, low cloud top height, surface emissivities, and cloud liquid water content successively from a set of HIRS and SCAMS channels. Analyses involving random errors in the assumed temperature and water vapor profiles and measurement errors in the theoretically computed radiances and brightness temperatures have been carried out to investigate the sensitivity of these errors on the retrieval program. Results of error analyses reveal that the cloud retrieval technique developed in this paper appears to be theoretically rigorous and practically feasible. The retrieval technique is then applied to Nimbus 6 HIRS and SCAMS data for a number of carefully selected cases associated with summertime convective cloud systems. Results of the satellite retrieved cloud parameters based on a combination of infrared and microwave channels appear to be in qualitative agreement with the available synoptic, surface and radar observations.

  7. Annual South American Forest Loss Estimates (1989-2011) Based on Passive Microwave Remote Sensing

    NASA Astrophysics Data System (ADS)

    van Marle, M.; van der Werf, G.; de Jeu, R.; Liu, Y.

    2014-12-01

    Vegetation dynamics, such as forest loss, are an important factor in global climate, but long-term and consistent information on these dynamics on continental scales is lacking. We have quantified large-scale forest loss over the 90s and 00s in the tropical biomes of South America using a passive-microwave satellite-based vegetation product. Our forest loss estimates are based on remotely sensed vegetation optical depth (VOD), which is an indicator of vegetation water content simultaneously retrieved with soil moisture. The advantage of low-frequency microwave remote sensing is that aerosols and clouds do not affect the observations. Furthermore, the longer wavelengths of passive microwaves penetrate deeper into vegetation than other products derived from optical and thermal sensors. This has the consequence that both woody parts of vegetation and leaves can be observed. The merged VOD product of AMSR-E and SSM/I observations, which covers over 23 years of daily observations, is used. We used this data stream and an outlier detection algorithm to quantify spatial and temporal variations in forest loss dynamics. Qualitatively, our results compared favorably to the newly developed Global Forest Change (GFC) maps based on Landsat data (r2=0.96), and this allowed us to convert the VOD outlier count to forest loss. Our results are spatially explicit with a 0.25-degree resolution and annual time step and we will present our estimates on country level. The added benefit of our results compared to GFC is the longer time period. The results indicate a relatively steady increase in forest loss in Brazil from 1989 until 2003, followed by two high forest loss years and a declining trend afterwards. This contrasts with other South American countries such as Bolivia and Peru, where forest losses increased in almost the whole 00s in comparison with the 90s.

  8. High-Resolution Daily Flood Extent Depiction from Microwave Remote Sensing: Global Results

    NASA Astrophysics Data System (ADS)

    Galantowicz, J. F.

    2015-12-01

    The need for frequent, accurate, high-resolution characterization of the temporal and spatial progression of flood hazards is evident, but has been beyond the capabilities of remote sensing methods. The surface is too often obscured by cloud cover for visual and infrared sensors and observations from radar sensors are too infrequent to create consistent historical databases or for monitoring current conditions. Passive microwave sensors, such as SSM/I, AMSR-E, and AMSR-2, acquire useful data during clear and cloudy conditions, have revisit periods of up to twice daily, and provide a continuous record of data from 1987 to the present. In this presentation, we will describe results from a flood mapping system capable of producing high-resolution (100-m) flood extent depictions from lower resolution (10-40-km) microwave data. The system uses the strong sensitivity of microwave data to surface water extent combined with land surface and atmospheric data to derive daily flooded fraction estimates globally on a sensor footprint basis. The system downscales flooded fraction to make a high-resolution Boolean flood extent depiction that is both spatially continuous and consistent with the lower resolution data (see Figure). The downscaling step is based on a relative floodability index derived from higher resolution topographic and hydrological data and processed to represent the minimum total water fraction threshold above which each grid point is expected to be flooded given microwave-derived water fraction inputs. We have completed daily, 100-m resolution flood maps for Africa for the 9.3-year AMSR-E period and will soon complete global flood maps fo the same period. We will present animations of daily flood extents during major events and discuss: validation of the flood maps against imagery derived from MODIS and Landsat data; analyses of minimum detectable flood size; statistical analyses of flooding over time; applications for this novel historical dataset; and

  9. Signatures of Hydrometeor Species from Airborne Passive Microwave Data for Frequencies 10-183 GHz

    NASA Technical Reports Server (NTRS)

    Cecil, Daniel J.; Leppert, Kenneth, II

    2014-01-01

    There are 2 basic precipitation retrieval methods using passive microwave measurements: (1) Emission-based: Based on the tendency of liquid precipitation to cause an increase in brightness temperature (BT) primarily at frequencies below 22 GHz over a radiometrically cold background, often an ocean background (e.g., Spencer et al. 1989; Adler et al. 1991; McGaughey et al. 1996); and (2) Scattering-based: Based on the tendency of precipitation-sized ice to scatter upwelling radiation, thereby reducing the measured BT over a relatively warmer (usually land) background at frequencies generally 37 GHz (e.g., Spencer et al. 1989; Smith et al. 1992; Ferraro and Marks 1995). Passive microwave measurements have also been used to detect intense convection (e.g., Spencer and Santek 1985) and for the detection of hail (e.g., Cecil 2009; Cecil and Blankenship 2012; Ferraro et al. 2014). The Global Precipitation Measurement (GPM) mission expands upon the successful Tropical Rainfall Measurement Mission program to provide global rainfall and snowfall observations every 3 hours (Hou et al. 2014). One of the instruments on board the GPM Core Observatory is the GPM Microwave Imager (GMI) which is a conically-scanning microwave radiometer with 13 channels ranging from 10-183 GHz. Goal of this study: Determine the signatures of various hydrometeor species in terms of BTs measured at frequencies used by GMI by using data collected on 3 case days (all having intense/severe convection) during the Mid-latitude Continental Convective Clouds Experiment conducted over Oklahoma in 2011.

  10. Remote Sensing of Chlorophyll Fluorescence by the Airborne Plant Fluorescence Sensor (APFS)

    NASA Astrophysics Data System (ADS)

    Yee, J. H.; Boldt, J.; Cook, W. B.; Morgan, F., II; Demajistre, R.; Cook, B. D.; Corp, L. A.

    2014-12-01

    Solar-induced chlorophyll fluorescence (ChlF) by terrestrial vegetation is linked closely to photosynthetic efficiency that can be exploited to monitor the plant health status and to assess the terrestrial carbon budget from space. The weak, broad continuum ChlF signal can be detected from the amount of fill-in of strong O2 absorption lines or Fraunhofer lines in the reflected solar spectral radiation. The Johns Hopkins University, Applied Physics Laboratory (JHU/APL) Airborne Plant Fluorescence Sensor (APFS) is designed and constructed specifically for airborne and groundbased ChlF measurements using the line fill-in ChlF measurement technique. In this paper, we will present the design of this triple etalon Fabry-Perot imaging instrument and the results of its vegetation fluorescence measurements obtained from the ground in the laboratory and from a NASA Langley King Air during our 2014 airborne campaign over vegetated targets in North Carolina and Virginia.

  11. Remote sensing and airborne geophysics in the assessment of natural aggregate resources

    USGS Publications Warehouse

    Knepper, D.H.; Langer, W.H.; Miller, S.H.

    1994-01-01

    Natural aggregate made from crushed stone and deposits of sand and gravel is a vital element of the construction industry in the United States. Although natural aggregate is a high volume/low value commodity that is relatively abundant, new sources of aggregate are becoming increasingly difficult to find and develop because of rigid industry specifications, political considerations, development and transporation costs, and environmental concerns, especially in urban growth centers where much of the aggregate is used. As the demand for natural aggregate increases in response to urban growth and the repair and expansion of the national infrastructure, new sources of natural aggregate will be required. The USGS has recognized the necessity of developing the capability to assess the potential for natural aggregate sources on Federal lands; at present, no methodology exists for systematically describing and evaluating potential sources of natural aggregate. Because remote sensing and airborne geophysics can detect surface and nearsurface phenomena, these tools may useful for detecting and mapping potential sources of natural aggregate; however, before a methodology for applying these tools can be developed, it is necessary to understand the type, distribution, physical properties, and characteristics of natural aggregate deposits, as well as the problems that will be encountered in assessing their potential value. There are two primary sources of natural aggregate: (1) exposed or near-surface igneous, metamorphic, and sedimentary bedrock that can be crushed, and (2) deposits of sand and gravel that may be used directly or crushed and sized to meet specifications. In any particular area, the availability of bedrock suitable for crushing is a function of the geologic history of the area - the processes that formed, deformed, eroded and exposed the bedrock. Deposits of sand and gravel are primarily surficial deposits formed by the erosion, transportation by water and ice

  12. Geometric correction of airborne remote sensing data: An operational procedure to geocode MIVIS data

    SciTech Connect

    Avanzi, G.; Bianchi, R.; Cavalli, R.M.

    1996-11-01

    Study to develop a software methodology to geocode MIVIS hyperspectral images collected by the CNR LARA Project. Gol of the study is to integrate the airborne Position and Attitude System with the image data to obtain geoceded images at a medium-small scale (1: 15000 - 1: 10000). 4 refs., 4 figs.

  13. Converting Snow Depth to SWE: The Fusion of Simulated Data with Remote Sensing Retrievals and the Airborne Snow Observatory

    NASA Astrophysics Data System (ADS)

    Bormann, K.; Marks, D. G.; Painter, T. H.; Hedrick, A. R.; Deems, J. S.

    2015-12-01

    Snow cover monitoring has greatly benefited from remote sensing technology but, despite their critical importance, spatially distributed measurements of snow water equivalent (SWE) in mountain terrain remain elusive. Current methods of monitoring SWE rely on point measurements and are insufficient for distributed snow science and effective management of water resources. Many studies have shown that the spatial variability in SWE is largely controlled by the spatial variability in snow depth. JPL's Airborne Snow Observatory mission (ASO) combines LiDAR and spectrometer instruments to retrieve accurate and very high-resolution snow depth measurements at the watershed scale, along with other products such as snow albedo. To make best use of these high-resolution snow depths, spatially distributed snow density data are required to leverage SWE from the measured snow depths. Snow density is a spatially and temporally variable property that cannot yet be reliably extracted from remote sensing techniques, and is difficult to extrapolate to basin scales. However, some physically based snow models have shown skill in simulating bulk snow densities and therefore provide a pathway for snow depth to SWE conversion. Leveraging model ability where remote sensing options are non-existent, ASO employs a physically based snow model (iSnobal) to resolve distributed snow density dynamics across the basin. After an adjustment scheme guided by in-situ data, these density estimates are used to derive the elusive spatial distribution of SWE from the observed snow depth distributions from ASO. In this study, we describe how the process of fusing model data with remote sensing retrievals is undertaken in the context of ASO along with estimates of uncertainty in the final SWE volume products. This work will likely be of interest to those working in snow hydrology, water resource management and the broader remote sensing community.

  14. Airborne Particles: What We Have Learned About Their Role in Climate from Remote Sensing, and Prospects for Future Advances

    NASA Technical Reports Server (NTRS)

    Kahn, Ralph A.

    2013-01-01

    Desert dust, wildfire smoke, volcanic ash, biogenic and urban pollution particles, all affect the regional-scale climate of Earth in places and at times; some have global-scale impacts on the column radiation balance, cloud properties, atmospheric stability structure, and circulation patterns. Remote sensing has played a central role in identifying the sources and transports of airborne particles, mapping their three-dimensional distribution and variability, quantifying their amount, and constraining aerosol air mass type. The measurements obtained from remote sensing have strengths and limitations, and their value for characterizing Earths environment is enhanced immensely when they are combined with direct, in situ observations, and used to constrain aerosol transport and climate models. A similar approach has been taken to study the role particles play in determining the climate of Mars, though based on far fewer observations. This presentation will focus what we have learned from remote sensing about the impacts aerosol have on Earths climate; a few points about how aerosols affect the climate of Mars will also be introduced, in the context of how we might assess aerosol-climate impacts more generally on other worlds.

  15. Comparisons of Arctic In-Situ Snow and Ice Data with Airborne Passive Microwave Measurements

    NASA Technical Reports Server (NTRS)

    Markus, T.; Cavalien, D. J.; Gasiewski, A.; Sturm, M.; Klein, M.; Maslanik, J.; Stroeve, J.; Heinrichs, J.; Holmgren, J.; Irisov, V.

    2004-01-01

    As part of the AMSR-E sea ice validation campaign in March 2003, aircraft flights over the Arctic sea ice were coordinated with ground measurements of snow and sea ice properties. The surface-based measurements were in the vicinity of Barrow, AK, and at a Navy ice camp located in the Beaufort Sea. The NASA P-3 aircraft was equipped with the NOAA ETL PSR microwave radiometer that has the same frequencies as the AMSR-E sensor. The goal was to validate the standard AMSR-E products ice temperature and snow depth on sea ice. Ground measurements are the only way to validate these parameters. The higher spatial resolution of the PSR instrument (between 30 and 500 m, depending on altitude) enables a better comparison between ground measurements and microwave data because of the expected smaller spatial variability. Maps of PSR data can then be used for further down-scaling to AMSR-E pixel areas. Initial results show a good qualitative agreement between the in-situ snow depths and the PSR data. Detailed studies are underway and latest results will be presented.

  16. Assessment of EOS Aqua AMSR-E Arctic Sea Ice Concentrations using Landsat-7 and Airborne Microwave Imagery

    NASA Technical Reports Server (NTRS)

    Cavalieri, Donald J.; Markus, Thorsten; Hall, Dorothy K.; Gasiewski, Albin J.; Klein, Marian; Ivanoff, Alvaro

    2006-01-01

    An assessment of Advanced Microwave Scanning Radiometer Earth Observing System (AMSR-E) sea ice concentrations under winter conditions using ice concentrations derived from Landsat-7 Enhanced Thematic Mapper Plus (ETM+) imagery obtained during the March 2003 Arctic sea ice validation field campaign is presented. The National Oceanic and Atmospheric Administration Environmental Technology Laboratory's Airborne Polarimetric Scanning Radiometer Measurements, which were made from the National Aeronautics and Space Administration P 3B aircraft during the campaign, were used primarily as a diagnostic tool to understand the comparative results and to suggest improvements to the AMSR-E ice concentration algorithm. Based on the AMSR-E/ETM+ comparisons, a good overall agreement with little bias (approx. 1%) for areas of first year and young sea ice was found. Areas of new ice production result in a negative bias of about 5% in the AMSR-E ice concentration retrievals, with a root mean square error of 8%. Some areas of deep snow also resulted in an underestimate of the ice concentration (approx. 10%). For all ice types combined and for the full range of ice concentrations, the bias ranged from 0% to 3%, and the rms errors ranged from 1% to 7%, depending on the region. The new-ice and deep-snow biases are expected to be reduced through an adjustment of the new-ice and ice-type C algorithm tie points.

  17. A new airborne Ka-band double-antenna microwave radiometer for cloud liquid water content measurement

    NASA Astrophysics Data System (ADS)

    Sun, Jian; Zhao, Kai; Jiang, Tao; Gu, Lingjia

    2013-09-01

    A new type upward-looking airborne double-antenna microwave radiometer (ADAMR) system intended for detecting atmospheric cloud liquid water content (LWC) is developed in this paper. The frequency of this radiometer is 31.65 GHz. For the antenna elevation angle, one is 30°and the other is 90°. In order to detect the signals with low effective noise temperature (<10K) from the LWC, the noise coupling technique is used. Through injecting constant equal noise signal into the two antenna ports respectively, the technique can elevate the small input noise signal power to the detectable range of the square-law detector and thus realize the weak signal detection. Moreover, in order to eliminate the impacts of the system gain fluctuations and obtain a higher sensitivity, an auto-gain compensation method based on the analog-to-digital converter, microcontroller and host computer software techniques is also proposed. Compared with the traditional radiometers, the radiometer topology is greatly simplified and the gain fluctuations can be readily realtime compensated using the compensation method. The laboratory test results show that radiometric sensitivity is better than 0.2 K for 300ms integration time and the instrument is conforming to specifications. Finally, the flight observation experiment results are presented to prove that the designed instrument is able to detect small changes of noise signal in a wide effective range of noise temperature (10-350K) and is a powerful tool for LWC measurement.

  18. Sea-surface temperature and salinity mapping from remote microwave radiometric measurements of brightness temperature

    NASA Technical Reports Server (NTRS)

    Hans-Juergen, C. B.; Kendall, B. M.; Fedors, J. C.

    1977-01-01

    A technique to measure remotely sea surface temperature and salinity was demonstrated with a dual frequency microwave radiometer system. Accuracies in temperature of 1 C and in salinity of part thousand for salinity greater than 5 parts per thousand were attained after correcting for the influence of extraterrestrial background radiation, atmospheric radiation and attenuation, sea-surface roughness, and antenna beamwidth. The radiometers, operating at 1.43 and 2.65 GHz, comprise a third-generation system using null balancing and feedback noise injection. Flight measurements from an aircraft at an altitude of 1.4 km over the lower Chesapeake Bay and coastal areas of the Atlantic Ocean resulted in contour maps of sea-surface temperature and salinity with a spatial resolution of 0.5 km.

  19. Progress in passive microwave remote sensing - Nonlinear retrieval techniques. [for meteorological parameters

    NASA Technical Reports Server (NTRS)

    Staelin, D. H.

    1980-01-01

    A variety of nonlinear retrieval methods have been applied to passive microwave remote sensing problems. These problems can be characterized in part by the degree to which their underlying physics and statistics can be understood and characterized in a simple way. Four examples of varying complexity are considered here; the simplest problem requires only analytic expressions for retrievals, whereas the most complex problem has been handled only with pattern classification techniques. The four examples are: (1) Doppler measurements of winds at 70 to 100 km, (2) retrieval of atmospheric water vapor profiles using the opaque 183-GHz water vapor resonance, (3) retrieval of snow accumulation rate by means of combined theoretical and empirical procedures, and (4) classification of diverse polar terrain by means of pattern recognition techniques.

  20. ESA activities in the use of microwaves for the remote sensing of the Earth

    NASA Technical Reports Server (NTRS)

    Maccoll, D.

    1984-01-01

    The program of activities under way in the European Space Agency (ESA) directed towards Remote Sensing of the oceans and troposphere is discussed. The initial project is the launch of a satellite named ERS-1 with a primary payload of microwave values in theee C- and Ku-bands. This payload is discussed in depth. The secondary payload includes precision location experiments and an instrument to measure sea surface temperature, which are described. The important topic of calibration is extensively discussed, and a review of activities directed towards improvements to the instruments for future satellites is presented. Some discussion of the impact of the instrument payload on the spacecraft design follows and the commitment of ESA to the provision of a service of value to the ultimate user is emphasized.

  1. Microwave backscattering theory and active remote sensing of the ocean surface

    NASA Technical Reports Server (NTRS)

    Brown, G. S.; Miller, L. S.

    1977-01-01

    The status is reviewed of electromagnetic scattering theory relative to the interpretation of microwave remote sensing data acquired from spaceborne platforms over the ocean surface. Particular emphasis is given to the assumptions which are either implicit or explicit in the theory. The multiple scale scattering theory developed during this investigation is extended to non-Gaussian surface statistics. It is shown that the important statistic for the case is the probability density function of the small scale heights conditioned on the large scale slopes; this dependence may explain the anisotropic scattering measurements recently obtained with the AAFE Radscat. It is noted that present surface measurements are inadequate to verify or reject the existing scattering theories. Surface measurements are recommended for qualifying sensor data from radar altimeters and scatterometers. Additional scattering investigations are suggested for imaging type radars employing synthetically generated apertures.

  2. Volumetric pattern analysis of fuselage-mounted airborne antennas. Ph.D. Thesis; [prediction analysis techniques for antenna radiation patterns of microwave antennas on commercial aircraft

    NASA Technical Reports Server (NTRS)

    Yu, C. L.

    1976-01-01

    A volumetric pattern analysis of fuselage-mounted airborne antennas at high frequencies was investigated. The primary goal of the investigation was to develop a numerical solution for predicting radiation patterns of airborne antennas in an accurate and efficient manner. An analytical study of airborne antenna pattern problems is presented in which the antenna is mounted on the fuselage near the top or bottom. Since this is a study of general-type commercial aircraft, the aircraft was modeled in its most basic form. The fuselage was assumed to be an infinitely long perfectly conducting elliptic cylinder in its cross-section and a composite elliptic cylinder in its elevation profile. The wing, cockpit, stabilizers (horizontal and vertical) and landing gear are modeled by "N" sided bent or flat plates which can be arbitrarily attached to the fuselage. The volumetric solution developed utilizes two elliptic cylinders, namely, the roll plane and elevation plane models to approximate the principal surface profile (longitudinal and transverse) at the antenna location. With the belt concept and the aid of appropriate coordinate system transformations the solution can be used to predict the volumetric patterns of airborne antennas in an accurate and efficient manner. Applications of this solution to various airborne antenna problems show good agreement with scale model measurements. Extensive data are presented for a microwave landing antenna system.

  3. Satellite Microwave Remote Sensing for Environmental Modeling of Mosquito Population Dynamics.

    PubMed

    Chuang, Ting-Wu; Henebry, Geoffrey M; Kimball, John S; Vanroekel-Patton, Denise L; Hildreth, Michael B; Wimberly, Michael C

    2012-10-01

    Environmental variability has important influences on mosquito life cycles and understanding the spatial and temporal patterns of mosquito populations is critical for mosquito control and vector-borne disease prevention. Meteorological data used for model-based predictions of mosquito abundance and life cycle dynamics are typically acquired from ground-based weather stations; however, data availability and completeness are often limited by sparse networks and resource availability. In contrast, environmental measurements from satellite remote sensing are more spatially continuous and can be retrieved automatically. This study compared environmental measurements from the NASA Advanced Microwave Scanning Radiometer on EOS (AMSR-E) and in situ weather station data to examine their ability to predict the abundance of two important mosquito species (Aedes vexans and Culex tarsalis) in Sioux Falls, South Dakota, USA from 2005 to 2010. The AMSR-E land parameters included daily surface water inundation fraction, surface air temperature, soil moisture, and microwave vegetation opacity. The AMSR-E derived models had better fits and higher forecasting accuracy than models based on weather station data despite the relatively coarse (25-km) spatial resolution of the satellite data. In the AMSR-E models, air temperature and surface water fraction were the best predictors of Aedes vexans, whereas air temperature and vegetation opacity were the best predictors of Cx. tarsalis abundance. The models were used to extrapolate spatial, seasonal, and interannual patterns of climatic suitability for mosquitoes across eastern South Dakota. Our findings demonstrate that environmental metrics derived from satellite passive microwave radiometry are suitable for predicting mosquito population dynamics and can potentially improve the effectiveness of mosquito-borne disease early warning systems.

  4. Satellite Microwave Remote Sensing for Environmental Modeling of Mosquito Population Dynamics.

    PubMed

    Chuang, Ting-Wu; Henebry, Geoffrey M; Kimball, John S; Vanroekel-Patton, Denise L; Hildreth, Michael B; Wimberly, Michael C

    2012-10-01

    Environmental variability has important influences on mosquito life cycles and understanding the spatial and temporal patterns of mosquito populations is critical for mosquito control and vector-borne disease prevention. Meteorological data used for model-based predictions of mosquito abundance and life cycle dynamics are typically acquired from ground-based weather stations; however, data availability and completeness are often limited by sparse networks and resource availability. In contrast, environmental measurements from satellite remote sensing are more spatially continuous and can be retrieved automatically. This study compared environmental measurements from the NASA Advanced Microwave Scanning Radiometer on EOS (AMSR-E) and in situ weather station data to examine their ability to predict the abundance of two important mosquito species (Aedes vexans and Culex tarsalis) in Sioux Falls, South Dakota, USA from 2005 to 2010. The AMSR-E land parameters included daily surface water inundation fraction, surface air temperature, soil moisture, and microwave vegetation opacity. The AMSR-E derived models had better fits and higher forecasting accuracy than models based on weather station data despite the relatively coarse (25-km) spatial resolution of the satellite data. In the AMSR-E models, air temperature and surface water fraction were the best predictors of Aedes vexans, whereas air temperature and vegetation opacity were the best predictors of Cx. tarsalis abundance. The models were used to extrapolate spatial, seasonal, and interannual patterns of climatic suitability for mosquitoes across eastern South Dakota. Our findings demonstrate that environmental metrics derived from satellite passive microwave radiometry are suitable for predicting mosquito population dynamics and can potentially improve the effectiveness of mosquito-borne disease early warning systems. PMID:23049143

  5. Status of microwave process development for RH-TRU (remote-handled transuranic) wastes at Oak Ridge National Laboratory

    SciTech Connect

    White, T.L.; Youngblood, E.L.; Berry, J.B.; Mattus, A.J.

    1990-01-01

    The Oak Ridge National Laboratory (ORNL) Waste Handling and Packaging Plant is developing a microwave process to reduce and solidify remote-handled transuranic (RH-TRU) liquids and sludges presently stored in large tanks at ORNL. Testing has recently begun on an in-drum microwave process using nonradioactive RH-TRU surrogates. The microwave process development effort has focused on an in-drum process to dry the RH-TRU liquids and sludges in the final storage container and then melt the salt residues to form a solid monolith. A 1/3-scale proprietary microwave applicator was designed, fabricated, and tested to demonstrate the essential features of the microwave design and to provide input into the design of the full-scale applicator. The microwave fields are uniform in one dimension to reduce the formation of hot spots on the microwaved wasteform. The final wasteform meets the waste acceptance criteria for the Waste Isolation Pilot Plant, a federal repository for defense transuranic wastes near Carlsbad, New Mexico. 7 refs., 1 fig., 1 tab.

  6. Airborne Optical and Thermal Remote Sensing for Wildfire Detection and Monitoring.

    PubMed

    Allison, Robert S; Johnston, Joshua M; Craig, Gregory; Jennings, Sion

    2016-08-18

    For decades detection and monitoring of forest and other wildland fires has relied heavily on aircraft (and satellites). Technical advances and improved affordability of both sensors and sensor platforms promise to revolutionize the way aircraft detect, monitor and help suppress wildfires. Sensor systems like hyperspectral cameras, image intensifiers and thermal cameras that have previously been limited in use due to cost or technology considerations are now becoming widely available and affordable. Similarly, new airborne sensor platforms, particularly small, unmanned aircraft or drones, are enabling new applications for airborne fire sensing. In this review we outline the state of the art in direct, semi-automated and automated fire detection from both manned and unmanned aerial platforms. We discuss the operational constraints and opportunities provided by these sensor systems including a discussion of the objective evaluation of these systems in a realistic context.

  7. Airborne Optical and Thermal Remote Sensing for Wildfire Detection and Monitoring

    PubMed Central

    Allison, Robert S.; Johnston, Joshua M.; Craig, Gregory; Jennings, Sion

    2016-01-01

    For decades detection and monitoring of forest and other wildland fires has relied heavily on aircraft (and satellites). Technical advances and improved affordability of both sensors and sensor platforms promise to revolutionize the way aircraft detect, monitor and help suppress wildfires. Sensor systems like hyperspectral cameras, image intensifiers and thermal cameras that have previously been limited in use due to cost or technology considerations are now becoming widely available and affordable. Similarly, new airborne sensor platforms, particularly small, unmanned aircraft or drones, are enabling new applications for airborne fire sensing. In this review we outline the state of the art in direct, semi-automated and automated fire detection from both manned and unmanned aerial platforms. We discuss the operational constraints and opportunities provided by these sensor systems including a discussion of the objective evaluation of these systems in a realistic context. PMID:27548174

  8. Airborne Optical and Thermal Remote Sensing for Wildfire Detection and Monitoring.

    PubMed

    Allison, Robert S; Johnston, Joshua M; Craig, Gregory; Jennings, Sion

    2016-01-01

    For decades detection and monitoring of forest and other wildland fires has relied heavily on aircraft (and satellites). Technical advances and improved affordability of both sensors and sensor platforms promise to revolutionize the way aircraft detect, monitor and help suppress wildfires. Sensor systems like hyperspectral cameras, image intensifiers and thermal cameras that have previously been limited in use due to cost or technology considerations are now becoming widely available and affordable. Similarly, new airborne sensor platforms, particularly small, unmanned aircraft or drones, are enabling new applications for airborne fire sensing. In this review we outline the state of the art in direct, semi-automated and automated fire detection from both manned and unmanned aerial platforms. We discuss the operational constraints and opportunities provided by these sensor systems including a discussion of the objective evaluation of these systems in a realistic context. PMID:27548174

  9. Mining in subarctic Canada: airborne PM2.5 metal concentrations in two remote First Nations communities.

    PubMed

    Liberda, Eric N; Tsuji, Leonard J S; Peltier, Richard E

    2015-11-01

    Airborne particulate matter arising from upwind mining activities is a concern for First Nations communities in the western James Bay region of Ontario, Canada. Aerosol chemical components were collected in 2011 from two communities in northern Ontario. The chemical and mass concentration data of particulate matter collected during this study shows a significant difference in PM2.5 in Attawapiskat compared to Fort Albany. Elemental profiles indicate enhanced levels of some tracers thought to arise from mining activities, such as, K, Ni, and crustal materials. Both communities are remote and isolated from urban and industrial pollution sources, however, Attawapiskat First Nation has significantly enhanced levels of particulate matter, and it is likely that some of this arises from upwind mining activities. PMID:26255141

  10. Mining in subarctic Canada: airborne PM2.5 metal concentrations in two remote First Nations communities.

    PubMed

    Liberda, Eric N; Tsuji, Leonard J S; Peltier, Richard E

    2015-11-01

    Airborne particulate matter arising from upwind mining activities is a concern for First Nations communities in the western James Bay region of Ontario, Canada. Aerosol chemical components were collected in 2011 from two communities in northern Ontario. The chemical and mass concentration data of particulate matter collected during this study shows a significant difference in PM2.5 in Attawapiskat compared to Fort Albany. Elemental profiles indicate enhanced levels of some tracers thought to arise from mining activities, such as, K, Ni, and crustal materials. Both communities are remote and isolated from urban and industrial pollution sources, however, Attawapiskat First Nation has significantly enhanced levels of particulate matter, and it is likely that some of this arises from upwind mining activities.

  11. Airborne multispectral remote sensing data to estimate several oenological parameters in vineyard production. A case study of application of remote sensing data to precision viticulture in central Italy.

    NASA Astrophysics Data System (ADS)

    Tramontana, Gianluca; Girard, Filippo; Belli, Claudio; Comandini, Maria Cristina; Pietromarchi, Paolo; Tiberi, Domenico; Papale, Dario

    2010-05-01

    It is widely recognized that environmental differences within the vineyard, with respect to soils, microclimate, and topography, can influence grape characteristics and crop yields. Besides, the central Italy landscape is characterized by a high level of fragmentation and heterogeneity It requires stringent Remote sensing technical features in terms of spectral, geometric and temporal resolution to aimed at supporting applications for precision viticulture. In response to the needs of the Italian grape and wine industry for an evaluation of precision viticulture technologies, the DISAFRI (University of Tuscia) and the Agricultural Research Council - Oenological research unit (ENC-CRA) jointly carried out an experimental study during the year 2008. The study was carried out on 2 areas located in the town of Velletri, near Rome; for each area, two varieties (red and white grape) were studied: Nero d'Avola and Sauvignon blanc in first area , Merlot and Sauvignon blanc in second. Remote sensing data were acquired in different periods using a low cost multisensor Airborne remote sensing platform developed by DISAFRI (ASPIS-2 Advanced Spectroscopic Imager System). ASPIS-2, an evolution of the ASPIS sensor (Papale et al 2008, Sensors), is a multispectral sensor based on 4 CCD and 3 interferential filters per CCD. The filters are user selectable during the flight and in this way Aspis is able to acquire data in 12 bands in the visible and near infrared regions with a bandwidth of 10 or 20 nm. To the purposes of this study 7 spectral band were acquired and 15 vegetation indices calculated. During the ripeness period several vegetative and oenochemical parameters were monitored. Anova test shown that several oenochemical variables, such as sugars, total acidity, polyphenols and anthocyanins differ according to the variety taken into consideration. In order to evaluate the time autocorrelation of several oenological parameters value, a simple linear regression between

  12. Development and Evaluation of Global Wetlands Mappings from Coarse-Resolution Satellite Microwave Remote Sensing

    NASA Astrophysics Data System (ADS)

    Schroeder, R.; McDonald, K. C.; Podest, E.; Willacy, K.; Jones, L. A.; Kimball, J. S.; Zimmermann, R.

    2010-12-01

    Wetlands exert major impacts on global biogeochemistry, hydrology, and biological diversity. The extent and seasonal, interannual, and decadal variation of inundated wetland area play key roles in ecosystem dynamics. Wetlands contribute approximately one fourth of the total methane annually emitted to the atmosphere and are identified as the primary contributor to interannual variations in the growth rate of atmospheric methane concentrations. Despite the importance of these environments in the global cycling of carbon and water and to current and future climate, the extent and dynamics of global wetlands remain poorly characterized and modeled, primarily because of the scarcity of suitable regional-to-global remote-sensing data for characterizing their distribution and dynamics. We present a satellite-based approach for mapping wetlands globally at coarse-resolution (25km). The approach employs a mixture model applied to ~8 years (2002-2009) of daily 18.7 GHz, V and H polarization brightness temperature (Tb) data from the Advanced Microwave Scanning Radiometer on EOS (AMSR-E) and daily Ku-band (13.4 GHz) radar backscatter data from SeaWinds-on-QuikSCAT. The combined passive-active microwave mixture model approach utilizes site-specific MODIS IGBP land cover information to account for the effect of vegetation structure on the microwave remote sensing-based retrieval of surface inundation dynamics. A comparison with coarse-resolution global maps of fractional open water cover (Fw) derived from radiometric inversion of daily AMSR-E 18.7 GHz, V and H polarized Tb observations demonstrates agreement in terms of both spatial distribution and temporal variability of the major global wetland complexes, but differences in the magnitudes of the Fw retrievals. Wetlands products obtained from both satellite-based methods are compared with the high-resolution (250m) land water mask developed from MODIS and SRTM L3 (MOD44W) as well as the global lake and wetland database (GLWD

  13. Classification of Baltic Sea ice types by airborne multifrequency microwave radiometer

    SciTech Connect

    Kurvonen, L.; Hallikainen, M.

    1996-11-01

    An airborne multifrequency radiometer (24, 34, 48, and 94 GHz, vertical polarization) was used to investigate the behavior of the brightness temperature of different sea ice types in the Gulf of Bothnia (Baltic Sea). The measurements and the main results of the analysis are presented. The measurements were made in dry and wet conditions (air temperature above and below 0 C). The angle of incidence was 45{degree} in all measurements. The following topics are evaluated: (a) frequency dependency of the brightness temperature of different ice types, (b) the capability of the multifrequency radiometer to classify ice types for winter navigation purposes, and (c) the optimum measurement frequencies for mapping sea ice. The weather conditions had a significant impact on the radiometric signatures of some ice types (snow-covered compact pack ice and frost-covered new ice); the impact was the highest at 94 GHz. In all cases the overall classification accuracy was around 90% (the kappa coefficient was from 0.86 to 0.96) when the optimum channel combination (24/34 GHz and 94 GHz) was used.

  14. An airborne study of microwave surface sensing and boundary layer heat and moisture fluxes for FIFE

    NASA Technical Reports Server (NTRS)

    Gogineni, S. P.

    1995-01-01

    The objectives of this work were to perform imaging radar and scatterometer measurements over the Konza Prairie as a part of the First International land surface climatology project Field Experiments (EIFE) and to develop an mm-wave radiometer and the data acquisition system for this radiometer. We collected imaging radar data with the University of Kansas Side-Looking Airborne Radar (SLAR) operating at 9.375 GHz and scatterometer data with a helicopter-mounted scatterometer at 5.3 and 9.6 GHz. We also developed a 35-GHz null-balancing radiometer and data acquisition system. Although radar images showed good delineation of various features of the FIFE site, the data were not useful for quantitative analysis for extracting soil moisture information because of day-to-day changes in the system transfer characteristics. Our scatterometer results show that both C and X bands are sensitive to soil moisture variations over grass-covered soils. Scattering coefficients near vertical are about 4 dB lower for unburned areas because of the presence of a thatch layer, in comparison with those for burned areas. The results of the research have been documented in reports, oral presentations, and published papers.

  15. Airborne multi-spectral remote sensing with ground truth for areawide pest management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Scientists and researchers have been developing, integrating, and evaluating multiple strategies and technologies into a systems approach for management of field crop insect pests. Remote sensing along with Global Positioning Systems, Geographic Information Systems, and variable rate technology are...

  16. Airborne multispectral remote sensing with ground truth for areawide pest management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Scientists and engineers in areawide pest management programs have been developing, integrating, and evaluating multiple strategies and technologies into a systems approach for management of field crop insect pests. Remote sensing along with global positioning systems, geographic information system...

  17. Remote sensing of phytoplankton density and diversity in Narragansett Bay using an airborne fluorosensor

    NASA Technical Reports Server (NTRS)

    Farmer, F. H.; Brown, C. A., Jr.; Jarrett, O., Jr.; Campbell, J. W.; Staton, W. L.

    1979-01-01

    An aircraft-borne remote system is presented that utilizes narrow-band light from multiple dye lasers to excite selected algae photopigments and then measures the resultant flourescence emitted from chlorophyll a at 685 nm. Tests were conducted with both pure and mixed cultures of marine algae from a series of field tests taken from piers and bridges of Narragansett Bay, and a prototype remote fluorosensor was flown over the Bay during the 1978 winter-spring diatom bloom. Remote fluorescence obtained at hover points over sea-truth stations showed correlations with in situ fluorescence, total chlorophyll a, and cell count. It was concluded that the ratio of remote fluorescence to direct chlorophyll a concentration was less variable than expected, and the distribution of total chlorophyll a between two major photoplankton color groups showed three distinct areas, within the Bay, of green and golden-brown species.

  18. The Greenland ice sheet perennial firn aquifer: characteristics, extent and evolution obtained from airborne remote sensing

    NASA Astrophysics Data System (ADS)

    Miège, C.; Forster, R. R.; Koenig, L.; Brucker, L.; Box, J. E.; Burgess, E. W.

    2013-12-01

    The presence of a perennial firn aquifer (PFA) was identified April 2011, in the southeast part of the Greenland ice sheet, from firn-core drilling, surface- and airborne-radar. The PFA is a component of the ice sheet hydrology and corresponds to a liquid water saturated firn aquifer, which persists over the winter without freezing. The average depth of the top of the aquifer is ~20 m below the surface, and is guided by surface topography, following surface undulations, similar to an unconfined aquifer observed in other groundwater aquifer systems. We use a combination of 400 MHz ground-based radar and the 600 to 900 MHz Accumulation Radar on board NASA's airborne Operation IceBridge (OIB) to identify and map PFA extent and evolution between 2011 and 2013. Here, we present an ice-sheet wide mapping of the PFA, including the 2013 field campaign with detailed ground-based radar grids near the firn core site drilled in April 2013 (PFA-13, 66.18°N, 39.04°W and 1563 m). At the PFA-13 location, OIB Accumulation Radar and ground-based radar data were acquired along the same track within two weeks in both 2011 and 2013, offering a unique comparison dataset. This dataset is used to analyze the three year (2011-2013) evolution of PFA top depth, i.e. stored meltwater volume, in areas where radar transects are repeated from one year to the next. This evolution suggests possible horizontal flow of this stored meltwater toward the ice-sheet margins but must be confirmed by further field investigations. In addition, we derive surface slope from latest digital elevation model available for Southeast Greenland and use this slope as parameter to interpolate the PFA top in the area between ground radar transects and airborne radar flight lines. This slope interpolation would aim to improve PFA water volume/extent estimations for areas without airborne radar coverage. The fate of this stored meltwater is currently unknown, even if flow is suggested and drainage into nearby crevasses

  19. Relationships between evaprorative fraction and remotely sensed vegetation index and microwave brightness temperature for semiarid rangelands

    NASA Technical Reports Server (NTRS)

    Kustas, W. P.; Schimugge, T. J.; Humes, K. S.; Jackson, T. J.; Parry, R.; Weltz, M. A.; Moran, M. S.

    1993-01-01

    Measurements of the microwave brightness temperature (TB) with the Pushbroom Microwave Radiometer (PBMR) over the Walnut Gulch Experiment Watershed were made on selected days during the MONSOON 90 field campaign. The PBMR is an L-band instrument (21-cm wavelength) that can provide estimates of near-surface soil moisture over a variety of surfaces. Aircraft observations in the visible and near-infrared wavelengths collected on selected days also were used to compute a vegetation index. Continuous micrometeorological measurements and daily soil moisture samples were obtained at eight locations during experimental period. Two sites were instrumented with time domain reflectometry probes to monitor the soil moisture profile. The fraction of available energy used for evapotranspiration was computed by taking the ratio of latent heat flux (LE) to the sum of net radiation (Rn) and soil heat flux (G). This ratio is commonly called the evaporative fraction (EF) and normally varies between 0 and 1 under daytime convective conditions with minimal advection. A wide range of environmental conditions existed during the field campaign, resulting in average EF values for the study area varying from 0.4 to 0.8 and values of TB ranging from 220 to 280 K. Comparison between measured TB and EF for the eight locations showed an inverse relationship. Other days were included in the analysis by estimating TB with the soil moisture data. Because transpiration from the vegetation is more strongly coupled to root zone soil moisture, significant scatter in this relationship existed at high values of TB or dry near-surface soil moisture conditions. The variation in EF under dry near-surface soil moisture conditions was correlated to the amount of vegetation cover estimated with a remotely sensed vegetation index. These findings indicate that information obtained from optical and microwave data can be used for quantifying the energy balance of semiarid areas. The microwave data can indicate

  20. A change detection approach to flood mapping in urban areas using very high-resolution microwave remote sensing imagery

    NASA Astrophysics Data System (ADS)

    Giustarini, L.; Hostache, R.; Matgen, P.; Schumann, G.; Bates, P. D.; Mason, D. C.

    2012-04-01

    Very high-resolution Synthetic Aperture Radar sensors represent an alternative to aerial photography for delineating floods in built-up environments where flood risk is highest. However, even with currently available SAR image resolutions of 3 m and higher, signal returns from man-made structures hamper the accurate mapping of flooded areas. Enhanced image processing algorithms and a better exploitation of image archives are required to facilitate the use of microwave remote sensing data for monitoring flood dynamics in urban areas. This work presents a new way to efficiently process SAR data for enhanced flood detection. The purpose is to develop a fully automatic image classification method based on image statistics that can be applied to all existing SAR data sets and to different types of flooded regions, including urban settlements. A hybrid methodology combining radiometric thresholding, region growing and change detection is introduced as an approach enabling the automated, objective and reliable flood extent extraction from very high-resolution urban SAR images. The method is based on the calibration of a statistical distribution of "open water" backscatter values inferred from SAR images of floods. SAR images acquired during dry conditions enable the identification of i) areas that are located in "shadow" regions and are therefore not visible to the sensor and ii) areas that systematically behave as specular reflectors (e.g. smooth tarmac, permanent water bodies). Change detection with respect to a pre-flood reference image thereby reduces over-detection of inundated areas. A case study of the July 2007 Severn River flood (UK) observed by the very high-resolution SAR sensor on board TerraSAR-X as well as airborne photography highlights advantages and limitations of the proposed method. We conclude that the fully automated SAR-based flood mapping technique overcomes some limitations of state-of-the-art methods normally used. However, further technological

  1. Treatment of airborne asbestos and asbestos-like microfiber particles using atmospheric microwave air plasma.

    PubMed

    Averroes, A; Sekiguchi, H; Sakamoto, K

    2011-11-15

    Atmospheric microwave air plasma was used to treat asbestos-like microfiber particles that had two types of ceramic fiber and one type of stainless fiber. The treated particles were characterized via scanning electron microscopy (SEM) and X-ray diffraction (XRD). The experiment results showed that one type of ceramic fiber (Alumina:Silica=1:1) and the stainless fiber were spheroidized, but the other type of ceramic fiber (Alumina:Silica=7:3) was not. The conversion of the fibers was investigated by calculating the equivalent diameter, the aspect ratio, and the fiber content ratio. The fiber content ratio in various conditions showed values near zero. The relationship between the normalized fiber vanishing rate and the energy needed to melt the particles completely per unit surface area of projected particles, which is defined as η, was examined and seen to indicate that the normalized fiber vanishing rate decreased rapidly with the increase in η. Finally, some preliminary experiments for pure asbestos were conducted, and the analysis via XRD and phase-contrast microscopy (PCM) showed the availability of the plasma treatment. PMID:21962864

  2. Estimation of snow depth and snow water equivalent distribution using airborne microwave radiometry in the Binggou Watershed, the upper reaches of the Heihe River basin

    NASA Astrophysics Data System (ADS)

    Che, Tao; Dai, Liyun; Wang, Jian; Zhao, Kai; Liu, Qiang

    2012-07-01

    We estimated the spatial distribution of snow depth/snow water equivalent (SD/SWE) in a mountainous watershed (Binggou, which is in the upper reaches of the Heihe River basin) by an airborne microwave radiometry observational experiment. Two microwave radiometers measuring at K band (18.7 GHz) and Ka band (36 GHz) were used to estimate the volume scatter from snowpacks and infer SD and SWE. Simultaneously, the snow physical properties (such as snow depth, density, grain size and temperature) over four sites were measured, and a simple multi-layer sample scheme was adopted to obtain the stratigraphic information. The microwave emission model of layered snowpacks (MEMLS) was used to simulate the brightness temperatures of snow cover for each measurement point. By comparing TB data that were simulated by MEMLS and observed by radiometers on the aircraft over the four sites, we obtained the retrieval algorithms of SD and SWE based on brightness temperature differences (TBD) at the K- and Ka-bands that are suitable to the local snow properties. The validation shows that the mean absolute and relative errors of SD estimates are approximately 3.5 cm and 14.8%, respectively. SWE from airborne microwave radiometers show that blowing snow and sun radiation are two main factors that determine the spatial distribution of SWE in Binggou Watershed. The local angle of incidence of the microwave radiometer observation can be influenced by mountainous topography, and a sensitivity analysis suggests that changes in the local angle of incidence (e.g., the nominal angle of incidence) will not significantly influence the estimation of SD/SWE. The snow's stratigraphic condition is not an important factor for estimating SD/SWE in this study because the snow was not very deep in the Binggou Watershed. However, the field sampling scheme should be given more attention to obtain the spatial variations of snow properties and to support pixel-by-pixel validation in next field campaign.

  3. An Integrated Data Acquisition / User Request/ Processing / Delivery System for Airborne Remote Sensing Data

    NASA Astrophysics Data System (ADS)

    Chapman, B.; Chu, A.; Tung, W.

    2003-12-01

    Airborne science data has historically played an important role in the development of the scientific underpinnings for spaceborne missions. When the science community determines the need for new types of spaceborne measurements, airborne campaigns are often crucial in risk mitigation for these future missions. However, full exploitation of the acquired data may be difficult due to its experimental and transitory nature. Externally to the project, most problematic (in particular, for those not involved in requesting the data acquisitions) may be the difficulty in searching for, requesting, and receiving the data, or even knowing the data exist. This can result in a rather small, insular community of users for these data sets. Internally, the difficulty for the project is in maintaining a robust processing and archival system during periods of changing mission priorities and evolving technologies. The NASA/JPL Airborne Synthetic Aperture Radar (AIRSAR) has acquired data for a large and varied community of scientists and engineers for 15 years. AIRSAR is presently supporting current NASA Earth Science Enterprise experiments, such as the Soil Moisture EXperiment (SMEX) and the Cold Land Processes experiment (CLPX), as well as experiments conducted as many as 10 years ago. During that time, it's processing, data ordering, and data delivery system has undergone evolutionary change as the cost and capability of resources has improved. AIRSAR now has a fully integrated data acquisition/user request/processing/delivery system through which most components of the data fulfillment process communicate via shared information within a database. The integration of these functions has reduced errors and increased throughput of processed data to customers.

  4. Airborne methane remote measurements reveal heavy-tail flux distribution in Four Corners region

    PubMed Central

    Thorpe, Andrew K.; Thompson, David R.; Hulley, Glynn; Kort, Eric Adam; Vance, Nick; Borchardt, Jakob; Krings, Thomas; Gerilowski, Konstantin; Sweeney, Colm; Conley, Stephen; Bue, Brian D.; Aubrey, Andrew D.; Hook, Simon; Green, Robert O.

    2016-01-01

    Methane (CH4) impacts climate as the second strongest anthropogenic greenhouse gas and air quality by influencing tropospheric ozone levels. Space-based observations have identified the Four Corners region in the Southwest United States as an area of large CH4 enhancements. We conducted an airborne campaign in Four Corners during April 2015 with the next-generation Airborne Visible/Infrared Imaging Spectrometer (near-infrared) and Hyperspectral Thermal Emission Spectrometer (thermal infrared) imaging spectrometers to better understand the source of methane by measuring methane plumes at 1- to 3-m spatial resolution. Our analysis detected more than 250 individual methane plumes from fossil fuel harvesting, processing, and distributing infrastructures, spanning an emission range from the detection limit ∼ 2 kg/h to 5 kg/h through ∼ 5,000 kg/h. Observed sources include gas processing facilities, storage tanks, pipeline leaks, and well pads, as well as a coal mine venting shaft. Overall, plume enhancements and inferred fluxes follow a lognormal distribution, with the top 10% emitters contributing 49 to 66% to the inferred total point source flux of 0.23 Tg/y to 0.39 Tg/y. With the observed confirmation of a lognormal emission distribution, this airborne observing strategy and its ability to locate previously unknown point sources in real time provides an efficient and effective method to identify and mitigate major emissions contributors over a wide geographic area. With improved instrumentation, this capability scales to spaceborne applications [Thompson DR, et al. (2016) Geophys Res Lett 43(12):6571–6578]. Further illustration of this potential is demonstrated with two detected, confirmed, and repaired pipeline leaks during the campaign. PMID:27528660

  5. Airborne methane remote measurements reveal heavy-tail flux distribution in Four Corners region.

    PubMed

    Frankenberg, Christian; Thorpe, Andrew K; Thompson, David R; Hulley, Glynn; Kort, Eric Adam; Vance, Nick; Borchardt, Jakob; Krings, Thomas; Gerilowski, Konstantin; Sweeney, Colm; Conley, Stephen; Bue, Brian D; Aubrey, Andrew D; Hook, Simon; Green, Robert O

    2016-08-30

    Methane (CH4) impacts climate as the second strongest anthropogenic greenhouse gas and air quality by influencing tropospheric ozone levels. Space-based observations have identified the Four Corners region in the Southwest United States as an area of large CH4 enhancements. We conducted an airborne campaign in Four Corners during April 2015 with the next-generation Airborne Visible/Infrared Imaging Spectrometer (near-infrared) and Hyperspectral Thermal Emission Spectrometer (thermal infrared) imaging spectrometers to better understand the source of methane by measuring methane plumes at 1- to 3-m spatial resolution. Our analysis detected more than 250 individual methane plumes from fossil fuel harvesting, processing, and distributing infrastructures, spanning an emission range from the detection limit [Formula: see text] 2 kg/h to 5 kg/h through [Formula: see text] 5,000 kg/h. Observed sources include gas processing facilities, storage tanks, pipeline leaks, and well pads, as well as a coal mine venting shaft. Overall, plume enhancements and inferred fluxes follow a lognormal distribution, with the top 10% emitters contributing 49 to 66% to the inferred total point source flux of 0.23 Tg/y to 0.39 Tg/y. With the observed confirmation of a lognormal emission distribution, this airborne observing strategy and its ability to locate previously unknown point sources in real time provides an efficient and effective method to identify and mitigate major emissions contributors over a wide geographic area. With improved instrumentation, this capability scales to spaceborne applications [Thompson DR, et al. (2016) Geophys Res Lett 43(12):6571-6578]. Further illustration of this potential is demonstrated with two detected, confirmed, and repaired pipeline leaks during the campaign. PMID:27528660

  6. Design of an Airborne Portable Remote Imaging Spectrometer (PRISM) for the Coastal Ocean

    NASA Technical Reports Server (NTRS)

    Mouroulis, P.; vanGorp, B.; Green, R. O.; Cohen, D.; Wilson, D.; Randall, D.; Rodriguez, J.; Polanco, O.; Dierssen, H.; Balasubramanian, K.; Vargas, R.; Hein, R.; Sobel, H.; Eastwood, M.

    2010-01-01

    PRISM is a pushbroom imaging spectrometer currently under development at the Jet Propulsion Laboratory, intended to address the needs of airborne coastal ocean science research. We describe here the instrument design and the technologies that enable it to achieve its distinguishing characteristics. PRISM covers the 350-1050 nm range with a 3.1 nm sampling and a 33(deg) field of view. The design provides for high signal to noise ratio, high uniformity of response, and low polarization sensitivity. The complete instrument also incorporates two additional wavelength bands at 1240 and 1610 nm in a spot radiometer configuration to aid with atmospheric correction.

  7. Remotely Measured Terrestrial Chlorophyll Fluorescence Using Airborne G-LiHT and APFS Sensors

    NASA Astrophysics Data System (ADS)

    Cook, W. B.; Yee, J. H.; Corp, L. A.; Cook, B. D.; Huemmrich, K. F.

    2014-12-01

    In September 2014 the Goddard Lidar, Hyperspectral and Thermal (G-LiHT) and the APL/JHU Airborne Plant Fluorescence Sensor (APFS) were flown together on a NASA Langley King Air over vegetated targets in North Carolina and Virginia. The instruments provided high spatial and spectral resolution data in the visible and near infrared, down-welling irradiance, elevation maps, and thermal imagery. Ground validation data was also collected concurrently. Here we report the results of these measurements and show the feasibility of using these types of instruments for collection the fluorescence and other information essential for ecological and carbon cycle studies.

  8. Using Airborne Remote Sensing to Increase Situational Awareness in Civil Protection and Humanitarian Relief - the Importance of User Involvement

    NASA Astrophysics Data System (ADS)

    Römer, H.; Kiefl, R.; Henkel, F.; Wenxi, C.; Nippold, R.; Kurz, F.; Kippnich, U.

    2016-06-01

    Enhancing situational awareness in real-time (RT) civil protection and emergency response scenarios requires the development of comprehensive monitoring concepts combining classical remote sensing disciplines with geospatial information science. In the VABENE++ project of the German Aerospace Center (DLR) monitoring tools are being developed by which innovative data acquisition approaches are combined with information extraction as well as the generation and dissemination of information products to a specific user. DLR's 3K and 4k camera system which allow for a RT acquisition and pre-processing of high resolution aerial imagery are applied in two application examples conducted with end users: a civil protection exercise with humanitarian relief organisations and a large open-air music festival in cooperation with a festival organising company. This study discusses how airborne remote sensing can significantly contribute to both, situational assessment and awareness, focussing on the downstream processes required for extracting information from imagery and for visualising and disseminating imagery in combination with other geospatial information. Valuable user feedback and impetus for further developments has been obtained from both applications, referring to innovations in thematic image analysis (supporting festival site management) and product dissemination (editable web services). Thus, this study emphasises the important role of user involvement in application-related research, i.e. by aligning it closer to user's requirements.

  9. Road Asphalt Pavements Analyzed by Airborne Thermal Remote Sensing: Preliminary Results of the Venice Highway

    PubMed Central

    Pascucci, Simone; Bassani, Cristiana; Palombo, Angelo; Poscolieri, Maurizio; Cavalli, Rosa

    2008-01-01

    This paper describes a fast procedure for evaluating asphalt pavement surface defects using airborne emissivity data. To develop this procedure, we used airborne multispectral emissivity data covering an urban test area close to Venice (Italy).For this study, we first identify and select the roads' asphalt pavements on Multispectral Infrared Visible Imaging Spectrometer (MIVIS) imagery using a segmentation procedure. Next, since in asphalt pavements the surface defects are strictly related to the decrease of oily components that cause an increase of the abundance of surfacing limestone, the diagnostic absorption emissivity peak at 11.2μm of the limestone was used for retrieving from MIVIS emissivity data the areas exhibiting defects on asphalt pavements surface.The results showed that MIVIS emissivity allows establishing a threshold that points out those asphalt road sites on which a check for a maintenance intervention is required. Therefore, this technique can supply local government authorities an efficient, rapid and repeatable road mapping procedure providing the location of the asphalt pavements to be checked.

  10. Evaluation of the airborne imaging spectrometer for remote sensing of forest stand conditions

    NASA Technical Reports Server (NTRS)

    Olson, Charles E., Jr.

    1986-01-01

    Five pairs of plots were established in forest stands with one of each pair trenched and covered to prevent precipitation from reaching the tree roots. High winds and falling limbs destroyed the covers on three of the plots. The two remaining plots were in a red pine plantation and in a natural stand of sugar maple. Trees in both plots developed levels of moisture stress more than nine bars higher than control trees on the dates of overflights with the Airborne Imaging Spectrometer (AIS) and the Collins' Airborne Spectroradiometer (CAS). Hemispherical reflectance from stressed and control trees was measured with a Beckman DK2A spectrophotometer. On the day of the AIS overflight, stressed maple foliage was less reflective than the control from 1000 to 1300 nm, but more reflective at wavelengths longer than 1300 nm. Pine foliage was less reflective than the control from 1000 to 1600 nm, but the difference was small at wavelengths longer than 1350 nm. AIS data collected showed brightness values for both maple and pine to be lower than for the controls from 1000 to 1300 nm. CAS data were used to determine the gain in species identification accuracy obtainable with high spectral resolution data.

  11. DETECTION AND IDENTIFICATION OF TOXIC AIR POLLUTANTS USING FIELD PORTABLE AND AIRBORNE REMOTE IMAGING SYSTEMS

    EPA Science Inventory

    Remote sensing technologies are a class of instrument and sensor systems that include laser imageries, imaging spectrometers, and visible to thermal infrared cameras. These systems have been successfully used for gas phase chemical compound identification in a variety of field e...

  12. Multispectral Imaging Systems for Airborne Remote Sensing to Support Agricultural Production Management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Remote sensing has shown promise as a tool for managing agricultural application and production. Earth-observing satellite systems have an advantage for large-scale analysis at regional levels but are limited in spatial resolution. High-resolution satellite systems have been available in recent year...

  13. Data Management Challenges for Airborne NASA Earth Venture Sub-Orbital Investigations

    NASA Astrophysics Data System (ADS)

    Boyer, A.; Lindsley, C.; Wright, D.; Cook, R. B.; Santhana Vannan, S. K.

    2015-12-01

    The Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC) is developing technology infrastructure to archive airborne remote sensing observations from two of NASA's Earth Venture Sub-orbital Missions. The two missions are CARVE (Carbon in Arctic Reservoirs Vulnerability Experiment) and AirMOSS (Airborne Microwave Observatory of Subcanopy and Subsurface). These missions collected over 140 TB of data from extensive ground-based and airborne instruments. The metadata and documentation requirements necessary for proper archive and dissemination of such transect-based, and often 3-dimensional, airborne data are quite different from traditional field campaign data and satellite remote sensing data streams. Staff at the ORNL DAAC have developed a metadata and data infrastructure for airborne data that enables spatial or keyword-based search and discovery, integration of related satellite- or ground-based data sets, and subsetting and visualization tools for both CARVE and AirMOSS. Here we discuss challenges, progress, and lessons learned.

  14. Cloud-to-Ground Lightning Estimates Derived from SSMI Microwave Remote Sensing and NLDN

    NASA Technical Reports Server (NTRS)

    Winesett, Thomas; Magi, Brian; Cecil, Daniel

    2015-01-01

    Lightning observations are collected using ground-based and satellite-based sensors. The National Lightning Detection Network (NLDN) in the United States uses multiple ground sensors to triangulate the electromagnetic signals created when lightning strikes the Earth's surface. Satellite-based lightning observations have been made from 1998 to present using the Lightning Imaging Sensor (LIS) on the NASA Tropical Rainfall Measuring Mission (TRMM) satellite, and from 1995 to 2000 using the Optical Transient Detector (OTD) on the Microlab-1 satellite. Both LIS and OTD are staring imagers that detect lightning as momentary changes in an optical scene. Passive microwave remote sensing (85 and 37 GHz brightness temperatures) from the TRMM Microwave Imager (TMI) has also been used to quantify characteristics of thunderstorms related to lightning. Each lightning detection system has fundamental limitations. TRMM satellite coverage is limited to the tropics and subtropics between 38 deg N and 38 deg S, so lightning at the higher latitudes of the northern and southern hemispheres is not observed. The detection efficiency of NLDN sensors exceeds 95%, but the sensors are only located in the USA. Even if data from other ground-based lightning sensors (World Wide Lightning Location Network, the European Cooperation for Lightning Detection, and Canadian Lightning Detection Network) were combined with TRMM and NLDN, there would be enormous spatial gaps in present-day coverage of lightning. In addition, a globally-complete time history of observed lightning activity is currently not available either, with network coverage and detection efficiencies varying through the years. Previous research using the TRMM LIS and Microwave Imager (TMI) showed that there is a statistically significant correlation between lightning flash rates and passive microwave brightness temperatures. The physical basis for this correlation emerges because lightning in a thunderstorm occurs where ice is first

  15. Annual South American forest loss estimates based on passive microwave remote sensing (1990-2010)

    NASA Astrophysics Data System (ADS)

    van Marle, M. J. E.; van der Werf, G. R.; de Jeu, R. A. M.; Liu, Y. Y.

    2016-02-01

    Consistent forest loss estimates are important to understand the role of forest loss and deforestation in the global carbon cycle, for biodiversity studies, and to estimate the mitigation potential of reducing deforestation. To date, most studies have relied on optical satellite data and new efforts have greatly improved our quantitative knowledge on forest dynamics. However, most of these studies yield results for only a relatively short time period or are limited to certain countries. We have quantified large-scale forest loss over a 21-year period (1990-2010) in the tropical biomes of South America using remotely sensed vegetation optical depth (VOD). This passive microwave satellite-based indicator of vegetation water content and vegetation density has a much coarser spatial resolution than optical data but its temporal resolution is higher and VOD is not impacted by aerosols and cloud cover. We used the merged VOD product of the Advanced Microwave Scanning Radiometer (AMSR-E) and Special Sensor Microwave Imager (SSM/I) observations, and developed a change detection algorithm to quantify spatial and temporal variations in forest loss dynamics. Our results compared reasonably well with the newly developed Landsat-based Global Forest Change (GFC) maps, available for the 2001 onwards period (r2 = 0.90 when comparing annual country-level estimates). This allowed us to convert our identified changes in VOD to forest loss area and compute these from 1990 onwards. We also compared these calibrated results to PRODES (r2 = 0.60 when comparing annual state-level estimates). We found that South American forest exhibited substantial interannual variability without a clear trend during the 1990s, but increased from 2000 until 2004. After 2004, forest loss decreased again, except for two smaller peaks in 2007 and 2010. For a large part, these trends were driven by changes in Brazil, which was responsible for 56 % of the total South American forest loss area over our study

  16. Characterizing Open Water Bodies and Wetland Ecosystems Using Optical and Microwave Remote Sensing

    NASA Astrophysics Data System (ADS)

    Podest, E.; McDonald, K. C.; Jensen, K.; Schroeder, R.

    2015-12-01

    Inundated vegetation and open water bodies are common features across the landscape and exert major impacts on hydrologic processes and surface-atmosphere carbon exchange. Their carbon emissions can have a large impact on global climate. It is therefore of great importance to assess their spatial extent and temporal variations in order to improve upon carbon balance estimates. Despite their importance in the global cycling of carbon and water and climate forecasting, they remain poorly characterized and modeled, primarily because of the scarcity of suitable regional-to-global remote sensing data for characterizing wetlands distribution and dynamics. Spaceborne microwave sensors are an effective tool for characterizing these ecosystems since they are sensitive to surface water and vegetation structure, and they can monitor large areas on a temporal basis regardless of atmospheric conditions or solar illumination. Optical sensors however provide much higher spatial resolution as well as information on water color. We developed a methodology using data from the Advanced Land Observing Satellite (ALOS) Phased Array L-Band Synthetic Aperture Radar (PALSAR) to map wetland ecosystems at 100 meter resolution for target regions as well as SMAP radar data at 1 km resolution. We also used optical data from Landsat to map open water bodies and their color properties at 15 meter resolution. Inundation dynamics of these ecosystems was assessed using a coarser resolution, 25 km microwave product on surface water fraction, which was derived using combined active and passive microwave data from QuikSCAT and AMSR-E on a weekly basis. We compare information content and accuracy of the coarse resolution products to the PALSAR, SMAP and Landsat based datasets to ensure information harmonization. The combination of high and low resolution datasets will allow for characterization of wetlands and open water bodies and assessment of their flooding status. This work has been undertaken

  17. Annual South American forest loss estimates based on passive microwave remote sensing (1990-2010)

    NASA Astrophysics Data System (ADS)

    van Marle, M. J. E.; van der Werf, G. R.; de Jeu, R. A. M.; Liu, Y. Y.

    2015-07-01

    Consistent forest loss estimates are important to understand the role of forest loss and deforestation in the global carbon cycle, for biodiversity studies, and to estimate the mitigation potential of reducing deforestation. To date, most studies have relied on optical satellite data and new efforts have greatly improved our quantitative knowledge on forest dynamics. However, most of these studies yield results for only a relatively short time period or are limited to certain countries. We have quantified large-scale forest losses over a 21 year period (1990-2010) in the tropical biomes of South America using remotely sensed vegetation optical depth (VOD). This passive microwave satellite-based indicator of vegetation water content and vegetation density has a much coarser spatial resolution than optical but its temporal resolution is higher and VOD is not impacted by aerosols and cloud cover. We used the merged VOD product of the Advanced Microwave Scanning Radiometer (AMSR-E) and Special Sensor Microwave Imager (SSM/I) observations, and developed a change detection algorithm to quantify spatial and temporal variations in forest loss dynamics. Our results compared favorably to the newly developed Global Forest Change (GFC) maps based on Landsat data and available for the 2001 onwards period (r2 = 0.90 when comparing annual country-level estimates), which allowed us to convert our results to forest loss area and compute these from 1990 onwards. We found that South American forest exhibited substantial interannual variability without a clear trend during the 1990s, but increased from 2000 until 2004. After 2004, forest loss decreased again, except for two smaller peaks in 2007 and 2010. For a large part, these trends were driven by changes in Brazil, which was responsible for 56 % of the total South American forest loss over our study period according to our results. One of the key findings of our study is that while forest losses decreased in Brazil after 2005

  18. Sensitivity study for a remotely piloted microwave-powered sailplane used as a high-altitude observation

    NASA Technical Reports Server (NTRS)

    Turriziani, R. V.

    1979-01-01

    The sensitivity of several performance characteristics of a proposed design for a microwave-powered, remotely piloted, high-altitude sailplane to changes in independently varied design parameters was investigated. Results were expressed as variations from baseline values of range, final climb altitude and onboard storage of radiated energy. Calculated range decreased with increases in either gross weight or parasite drag coefficient; it also decreased with decreases in lift coefficient, propeller efficiency, or microwave beam density. The sensitivity trends for range and final climb altitude were very similar. The sensitivity trends for stored energy were reversed from those for range, except for decreasing microwave beam density. Some study results for single parameter variations were combined to estimate the effect of the simultaneous variation of several parameters: for two parameters, this appeared to give reasonably accurate results.

  19. The relationship among sea surface roughness variations, oceanographic analyses, and airborne remote sensing analyses

    NASA Technical Reports Server (NTRS)

    Oertel, G. F.; Wade, T. L.

    1981-01-01

    The synthetic aperture radar (SAR) was studied to determine whether it could image large scale estuaries and oceanic features such as fronts and to explain the electromagnetic interaction between SAR and the individual surface front features. Fronts were observed to occur at the entrance to the Chesapeake Bay. The airborne measurements consisted of data collection by SAR onboard an F-4 aircraft and real aperture side looking radar (SLAR) in Mohawk aircraft. A total of 89 transects were flown. Surface roughness and color as well as temperature and salinity were evaluated. Cross-frontal surveys were made. Frontal shear and convergence flow were obtained. Surface active organic materials, it was indicated, are present at the air-sea interface. In all, 2000 analyses were conducted to characterize the spatial and temporal variabilities associated with water mass boundaries.

  20. Multi-trophic invasion resistance in Hawaii: bioacoustics, field surveys, and airborne remote sensing.

    PubMed

    Boelman, Natalie T; Asner, Gregory P; Hart, Patrick J; Martin, Roberta E

    2007-12-01

    We used airborne imaging spectroscopy and scanning light detection and ranging (LiDAR), along with bioacoustic recordings, to determine how a plant species invasion affects avian abundance and community composition across a range of Hawaiian submontane ecosystems. Total avian abundance and the ratio of native to exotic avifauna were highest in habitats with the highest canopy cover and height. Comparing biophysically equivalent sites, stands dominated by native Metrosideros polymorpha trees hosted larger native avian communities than did mixed stands of Metrosideros and the invasive tree Morella faya. A multi-trophic analysis strongly suggests that native avifauna provide biotic resistance against the invasion of Morella trees and exotic birds, thus slowing invasion "meltdowns" that disrupt the functioning of native Hawaiian ecosystems. PMID:18213957

  1. Airborne remote sensing of ocean wave directional wavenumber spectra in the marginal ice zone

    NASA Astrophysics Data System (ADS)

    Sutherland, Peter; Gascard, Jean-Claude

    2016-05-01

    Interactions between surface waves and sea ice are thought to be an important, but poorly understood, physical process in the atmosphere-ice-ocean system. In this work, airborne scanning lidar was used to observe ocean waves propagating into the marginal ice zone (MIZ). These represent the first direct spatial measurements of the surface wavefield in the polar MIZ. Data were compared against two attenuation models, one based on viscous dissipation and one based on scattering. Both models were capable of reproducing the measured wave energy. The observed wavenumber dependence of attenuation was found to be consistent with viscous processes, while the spectral spreading of higher wavenumbers suggested a scattering mechanism. Both models reproduced a change in peak direction due to preferential directional filtering. Floe sizes were recorded using colocated visible imagery, and their distribution was found to be consistent with ice breakup by the wavefield.

  2. Remote estimation of canopy nitrogen content in winter wheat using airborne hyperspectral reflectance measurements

    NASA Astrophysics Data System (ADS)

    Zhou, Xianfeng; Huang, Wenjiang; Kong, Weiping; Ye, Huichun; Luo, Juhua; Chen, Pengfei

    2016-11-01

    Timely and accurate assessment of canopy nitrogen content (CNC) provides valuable insight into rapid and real-time nitrogen status monitoring in crops. A semi-empirical approach based on spectral index was extensively used for nitrogen content estimation. However, in many cases, due to specific vegetation types or local conditions, the applicability and robustness of established spectral indices for nitrogen retrieval were limited. The objective of this study was to investigate the optimal spectral index for winter wheat (Triticum aestivum L.) CNC estimation using Pushbroom Hyperspectral Imager (PHI) airborne hyperspectral data. Data collected from two different field experiments that were conducted during the major growth stages of winter wheat in 2002 and 2003 were used. Our results showed that a significant linear relationship existed between nitrogen and chlorophyll content at the canopy level, and it was not affected by cultivars, growing conditions and nutritional status of winter wheat. Nevertheless, it varied with growth stages. Periods around heading stage mainly worsened the relationship and CNC estimation, and CNC assessment for growth stages before and after heading could improve CNC retrieval accuracy to some extent. CNC assessment with PHI airborne hyperspectra suggested that spectral indices based on red-edge band including narrowband and broadband CIred-edge, NDVI-like and ND705 showed convincing results in CNC retrieval. NDVI-like and ND705 were sensitive to detect CNC changes less than 5 g/m2, narrowband and broadband CIred-edge were sensitive to a wide range of CNC variations. Further evaluation of CNC retrieval using field measured hyperspectra indicated that NDVI-like was robust and exhibited the highest accuracy in CNC assessment, and spectral indices (CIred-edge and CIgreen) that established on narrow or broad bands showed no obvious difference in CNC assessment. Overall, our study suggested that NDVI-like was the optimal indicator for winter

  3. Estimating sediment and caesium-137 fluxes in the Ribble Estuary through time-series airborne remote sensing.

    PubMed

    Wakefield, R; Tyler, A N; McDonald, P; Atkin, P A; Gleizon, P; Gilvear, D

    2011-03-01

    High spatial and temporal resolution airborne imagery were acquired for the Ribble Estuary, North West England in 1997 and 2003, to assess the application of time-series airborne remote sensing to quantify total suspended sediment and radionuclide fluxes during a flood and ebb tide sequence. Concomitant measurements of suspended particulate matter (SPM) and water column turbidity were obtained during the time-series image acquisition for the flood and ebb tide sequence on the 17th July 2003 to verify the assumption of a vertically well mixed estuary and thus justifying the vertical extrapolation of spatially integrated estimate of surface SPM. The ¹³⁷Cs activity concentrations were calculated from a relatively stable relationship between SPM and ¹³⁷Cs for the Ribble Estuary. Total estuary wide budgets of sediment and ¹³⁷Cs were obtained by combining the image-derived estimates of surface SPM and ¹³⁷Cs with estimates of water volume from a two-dimensional hydrodynamic model (VERSE) developed for the Ribble Estuary. These indicate that around 10,000 tons of sediment and 2.72 GBq of ¹³⁷Cs were deposited over the tidal sequence monitored in July 2003. This compared favourably with bed height elevation change estimated from field work. An uncertainty analysis on the total sediment and ¹³⁷Cs flux yielded a total budget of the order of 40% on the final estimate. The results represent a novel approach to providing a spatially integrated estimate of the total net sediment and radionuclide flux in an intertidal environment over a flood and ebb tide sequence.

  4. Passive and Active Microwave Remote Sensing of Precipitation and Latent Heating Distributions in the Tropics from TRMM

    NASA Technical Reports Server (NTRS)

    Olson, William S.; Kummerow, Christian D.; Yang, Song; Haddad, Ziad S.; Tao, Wei-Kuo; Wang, Yansen; Lang, Stephen E.; Braun, Scott A.; Chiu, Christine; Wang, Jian-Jian

    2002-01-01

    Passive and active microwave remote sensing data are analyzed to identify signatures of precipitation and vertical motion in tropical convection. A database of cloud/radiative model simulations is used to quantify surface rain rates and latent heating profiles that are consistent with these signatures. At satellite footprint-scale (approximately 10 km), rain rate and latent heating estimates are subject to significant random errors, but by averaging the estimates in space and time, random errors are substantially reduced, Bias errors have been minimized by improving the microphysics in the supporting cloud/radiative model simulations, and by imposing a consistent definition of remotely-sensed and model-simulated convective/stratiform rain coverage. Remotely-sensed precipitation and latent heating distributions in the tropics are derived from Tropical Rainfall Measuring Mission (TRMM) and Special Sensor Microwave/ Imager (SSM/ I) sensor data. The prototype Version 6 TRMM passive microwave algorithm typically yields average heating profiles with maxima between 6 and 7 km altitude for organized mesoscale convective systems. Retrieved heating profiles for individual convective systems are compared to coincident estimates based upon a combination of dual-Doppler radar and rawinsonde data. Also, large-scale latent heating distributions are compared to estimates derived from a simpler technique that utilizes observations of surface rain rate and stratiform rain proportion to infer vertical heating structure. Results of these tests will be presented at the conference.

  5. Interpretation of air pollution data as measured by an airborne remote sensor

    NASA Technical Reports Server (NTRS)

    Smith, G. L.; Young, G. R.; Green, R. N.

    1974-01-01

    The investigation described is a continuation of the work reported by Smith et al. (1974) in which a single source was studied. In the current study, multiple sources of known location are considered. The study is concerned with the strength of each source and the resulting pollution concentration field. The characteristics of the remotely sensed data are discussed along with the parameter estimation procedure, the estimation of pollution parameters, and a numerical example.

  6. Airborne Geophysics and Remote Sensing Applied to Study Greenland Ice Dynamics

    NASA Technical Reports Server (NTRS)

    Csatho, Beata M.

    2003-01-01

    Overview of project: we combined and jointly analysed geophysical, remote sensing and glaciological data for investigating the temporal changes in ice flow and the role of geologic control on glacial drainage. The project included two different studies, the investigation of recent changes of the Kangerlussuaq glacier and the study of geologic control of ice flow in NW Greenland, around the Humboldt, Petermann and Ryder glaciers.

  7. Airborne Remote Observations of L-Band Radio Frequency Interference and Implications for Satellite Missions

    NASA Technical Reports Server (NTRS)

    Laymon, Charles; Srinivasan, Karthik; Limaye, Ashutosh

    2011-01-01

    Passive remote sensing of the Earth s surface and atmosphere from space has significant importance in operational and research environmental studies, in particular for the scientific understanding, monitoring and prediction of climate change and its impacts. Passive remote sensing requires the measurement of naturally occurring radiations, usually of very low power levels, which contain essential information on the physical process under investigation. As such, these sensed radio frequency bands are a unique natural resource enabling space borne passive sensing of the atmosphere and the Earth s surface that deserves adequate allocation to the Earth Exploration Satellite Service and absolute protection from interference. Unfortunately, radio frequency interference (RFI) is an increasing problem for Earth remote sensing, particularly for passive observations of natural emissions. Because these natural signals tend to be very weak, even low levels of interference received by a passive sensor may degrade the fidelity of scientific data. The characteristics of RFI (low-level interference and radar-pulse noise) are not well known because there has been no systematic surveillance, spectrum inventory or mapping of RFI. While conducting a flight experiment over central Tennessee in May 2010, RFI, a concern for any instrument operating in the passive L band frequency, was observed across 16 subbands between 1402-1427 MHz. Such a survey provides rare characterization data from which to further develop mitigation technologies as well as to identify bandwidths to avoid in future sensor formulation.

  8. Microwave remote sensing of soil moisture content over bare and vegetated fields

    NASA Technical Reports Server (NTRS)

    Wang, J. R.; Shiue, J. C.; Mcmurtrey, J. E., III

    1980-01-01

    Remote measurements of soil moisture contents over bare fields and fields covered with orchard grass, corn, and soybean were made during October 1979 with 1.4 GHz and 5 GHz microwave radiometers mounted on a truck. Ground truth of soil moisture content, ambient air, and soil temperatures was acquired concurrently with the radiometric measurements. The biomass of the vegetation was sampled about once a week. The measured brightness temperatures over bare fields were compared with those of radiative transfer model calculations using as inputs the acquired soil moisture and temperature data with appropriate values of dielectric constants for soil-water mixtures. Good agreement was found between the calculated and the measured results over 10-70 deg incident angles. The presence of vegetation was found to reduce the sensitivity of soil moisture sensing. At 1.4 GHz the sensitivity reduction ranged from approximately 20% for 10-cm tall grassland to over 60% for the dense soybean field. At 5 GHz the corresponding reduction in sensitivity ranged from approximately 70 to approximately 90%.

  9. A mathematical characterization of vegetation effect on microwave remote sensing from the Earth

    NASA Technical Reports Server (NTRS)

    Choe, Y.; Tsang, L.

    1983-01-01

    In passive microwave remote sensing of the earth, a theoretical model that utilizes the radiative transfer equations was developed to account for the volume scattering effects of the vegetation canopy. Vegetation canopies such as alfalfa, sorghum, and corn are simulated by a layer of ellipsoidal scatterers and cylindrical structures. The ellipsoidal scatterers represent the leaves of vegetation and are randomly positioned and oriented. The orientation of ellipsoids is characterized by a probability density function of Eulerian angles of rotation. The cylindrical structures represent the stalks of vegetation and their radii are assumed to be much smaller than their lengths. The underlying soil is represented by a half-space medium with a homogeneous permittivity and uniform temperature profile. The radiative transfer quations are solved by a numerical method using a Gaussian quadrature formula to compute both the vertical and horizontal polarized brightness temperature as a function of observation angle. The theory was applied to the interpretation of experimental data obtained from sorghum covered fields near College Station, Texas.

  10. Polarimetric passive microwave remote sensing of wind vectors with foam-covered rough ocean surfaces

    NASA Astrophysics Data System (ADS)

    Zhou, Lin; Tsang, Leung; Chen, Dong

    2003-08-01

    In this paper, polarimetric microwave emissions from wind-generated foam-covered ocean surfaces are investigated. The foam is treated as densely packed air bubbles coated with thin seawater coating. The absorption, scattering and extinction coefficients are calculated by Monte Carlo simulations of solutions of Maxwell equations of a collection of coated particles. The effects of boundary roughness of ocean surface are included by using the second-order small perturbation method (SPM) describing the reflection coefficients between foam and ocean. An empirical wavenumber spectrum is used to represent the small-scale wind-generated sea surfaces. The iterative method is employed to solve dense media radiative transfer (DMRT) equations, and is applied to calculate results of all four Stokes parameters of rough ocean surfaces. The theoretical results of four Stokes brightness temperatures with typical parameters of foam in passive remote sensing at 10.8 GHz, 19 GHz and 36.5 GHz are illustrated. The azimuth variations of polarimetric brightness temperature are calculated. Emission with various wind speed and foam layer thickness is studied. The results are also compared with those based on Quasi-Crystalline Approximation (QCA).

  11. Microwave remote sensing of soil moisture content over bare and vegetated fields

    NASA Astrophysics Data System (ADS)

    Wang, J. R.; Shiue, J. C.; McMurtrey, J. E., III

    1980-10-01

    Remote measurements of soil moisture contents over bare fields and fields covered with orchard grass, corn, and soybean were made during October 1979 with 1.4 GHz and 5 GHz microwave radiometers mounted on a truck. Ground truth of soil moisture content, ambient air and soil temperatures was acquired concurrently with the radiometric measurements. The biomass of the vegetation was sampled about once a week. The measured brightness temperatures over bare fields were compared with those of radiative transfer model calculations using as inputs the acquired soil moisture and temperature data with appropriate values of dielectric constants for soil-water mixtures. Good agreement was found between the calculated and the measured results over 10°-70° incident angles. The presence of vegetation was found to reduce the sensitivity of soil moisture sensing. At 1.4 GHz the sensitivity reduction ranged from ˜20% for 10-cm tall grassland to over 60% for the dense soybean field. At 5 GHz the corresponding reduction in sensitivity ranged from ˜70% to ˜90%.

  12. The NASA/NSERC Student Airborne Research Program Land Focus Group - a Paid Training Program in Multi-Disciplinary STEM Research for Terrestrial Remote Sensing

    NASA Astrophysics Data System (ADS)

    Kefauver, S. C.; Ustin, S.; Davey, S. W.; Furey, B. J.; Gartner, A.; Kurzweil, D.; Siebach, K. L.; Slawsky, L.; Snyder, E.; Trammell, J.; Young, J.; Schaller, E.; Shetter, R. E.

    2011-12-01

    The Student Airborne Research Program (SARP) of the National Aeronautics and Space Administration (NASA) and the National Suborbital Education and Research Center (NSERC) is a unique six week multidisciplinary paid training program which directly integrates students into the forefront of airborne remote sensing science. Students were briefly trained with one week of lectures and laboratory exercises and then immediately incorporated into ongoing research projects which benefit from access to the DC-8 airborne platform and the MODIS-ASTER Airborne Simulator (MASTER) sensor. Students were split into three major topical categories of Land, Ocean, and Air for the data collection and project portions of the program. This poster details the techniques and structure used for the student integration into ongoing research, professional development, hypothesis building and results as developed by the professor and mentor of the Land focus group. Upon assignment to the Land group, students were issued official research field protocols and split into four field specialty groups with additional specialty reading assignments. In the field each group spent more time in their respective specialty, but also participated in all field techniques through pairings with UC Davis research team members using midday rotations. After the field campaign, each specialty group then gave summary presentations on the techniques, preliminary results, and significance to overall group objectives of their specialty. Then students were required to submit project proposals within the bounds of Land airborne remote sensing science and encouraging, but not requiring the use of the field campaign data. These proposals are then reviewed by the professor and mentor and students are met with one by one to discuss the skills of each student and objectives of the proposed research project. The students then work under the supervision of the mentor and benefit again from professor feedback in a formal

  13. Identification and Atmospheric Transport of Microcystin Around Southern California Using Airborne Remote Sensing

    NASA Astrophysics Data System (ADS)

    Conlin, J.; Kudela, R. M.; Broughton, J.

    2014-12-01

    Microcystin, a hepatotoxin produced by the cyanobacteria Microcystis, has been known to contaminate fresh water sources around southern California. Ingesting this toxin can cause death in animals and illnesses in humans, which has promoted the World Health Organization (WHO) and California to establish preliminary guidelines for microcystin concentrations in the water (1 μg/L in drinking water and 0.8 μg/L for recreational exposure respectively). However, very few studies have been done to assess the effects of this toxin when aerosolized, even though Fitzgeorge et al. (1994) describes the toxin as potentially 12x more deadly if inhaled rather than swallowed. This project aimed to identify areas with the potential for high microcystin concentrations using airborne data and then model the potential atmospheric transport of the toxin. After applying the Master Scattering Line Height (MSLH) and Aphanizomenon-Microcystis Index (AMI) algorithms to Airborne Visible/ Infrared Imaging Spectrometer (AVIRIS), multiple water bodies were identified as having the potential for Microcystis, although many of the observed water bodies had AMI values indicating the presence of Aphanizomenon-- a non-toxic cyanobacteria that is usually present before Microcystis. A relationship between toxins and biomass was developed and used to estimate the amount of phycocyanin and dissolved microcystin in the water. Brevetoxin, common in the Florida 'red tides', was used as a proxy to estimate the amount of microcystin that becomes aerosolized given a known water concentration (Kirkpatrick et al, 2010). These amounts were then run and averaged with the HYSPLIT dispersion model for 4 hours, 12 hours, and 24 hours. The final results show that most areas are exposed to less than 0.1 ng/m^3 after 4 hours. As a worst case scenario, one final model was run to show the exposure amount when Pinto Lake was observed to have the maximum amount of microcystin recorded in 2007. The results show that after 4

  14. A new algorithm to measure sea ice concentration from passive microwave remote sensing

    NASA Astrophysics Data System (ADS)

    Repina, Irina; Sharkov, Evgeniy; Komarova, Nataliya; Raev, Mikhail; Tikhonov, Vasilii; Boyarskiy, Dmitriy

    Studies of spatial and temporal properties of sea ice distribution in polar regions help to monitor global environmental changes and reveal their natural and anthropogenic factors, as well as make forecasts of weather, marine transportation and fishing conditions, assess perspectives of mineral mining on the continental shelf, etc. Contact methods of observation are often insufficient to meet the goals, very complicated technically and organizationally and not always safe for people involved. Remote sensing techniques are believed to be the best alternative. Its include monitoring of polar regions by means of passive microwave sensing with the aim to determine spatial distribution, types, thickness and snow cover of ice. However, the algorithms employed today to retrieve sea ice characteristics from passive microwave sensing data for different reasons give significant errors, especially in summer period and also near ice edges and in cases of open ice. One of the error sources is the current practice of using empirical dependencies and adjustment coefficients for the retrieval of ice characteristics and neglecting the physics of the process. We discuss an electrodynamic model of the sea surface - sea ice - snow cover - atmosphere system developed with account taken of physical and structural properties of the ambient. Model calculations of ice brightness temperature in different concentrations and snow covers are in good agreement with SSM/I measurement data. On the base of this model we develop a new algorithm for the retrieval of sea ice concentration from passive microwave sensing data - Variation Arctic Sea Ice Algorithm (VASIA). In contrast to the well-known techniques (NASA TEAM, Bootstrap, ASI, NORSEX et al), it takes into account the real physical parameters of ice, snow and open water rather than empirical and adjustment coefficients. Satellite data were provided by the POLE-RT-Fields SSM/I and SSMIS data collection for polar regions retrieved from the

  15. Mapping Weathering and Alteration Minerals in the Comstock and Geiger Grade Areas using Visible to Thermal Infrared Airborne Remote Sensing Data

    NASA Technical Reports Server (NTRS)

    Vaughan, Greg R.; Calvin, Wendy M.

    2005-01-01

    To support research into both precious metal exploration and environmental site characterization a combination of high spatial/spectral resolution airborne visible, near infrared, short wave infrared (VNIR/SWIR) and thermal infrared (TIR) image data were acquired to remotely map hydrothermal alteration minerals around the Geiger Grade and Comstock alteration regions, and map the mineral by-products of weathered mine dumps in Virginia City. Remote sensing data from the Airborne Visible Infrared Imaging Spectrometer (AVIRIS), SpecTIR Corporation's airborne hyperspectral imager (HyperSpecTIR), the MODIS-ASTER airborne simulator (MASTER), and the Spatially Enhanced Broadband Array Spectrograph System (SEBASS) were acquired and processed into mineral maps based on the unique spectral signatures of image pixels. VNIR/SWIR and TIR field spectrometer data were collected for both calibration and validation of the remote data sets, and field sampling, laboratory spectral analyses and XRD analyses were made to corroborate the surface mineralogy identified by spectroscopy. The resulting mineral maps show the spatial distribution of several important alteration minerals around each study area including alunite, quartz, pyrophyllite, kaolinite, montmorillonite/muscovite, and chlorite. In the Comstock region the mineral maps show acid-sulfate alteration, widespread propylitic alteration and extensive faulting that offsets the acid-sulfate areas, in contrast to the larger, dominantly acid-sulfate alteration exposed along Geiger Grade. Also, different mineral zones within the intense acid-sulfate areas were mapped. In the Virginia City historic mining district the important weathering minerals mapped include hematite, goethite, jarosite and hydrous sulfate minerals (hexahydrite, alunogen and gypsum) located on mine dumps. Sulfate minerals indicate acidic water forming in the mine dump environment. While there is not an immediate threat to the community, there are clearly sources of

  16. Novel compact airborne platform for remote sensing applications using the Hyper-Cam infrared hyperspectral imager

    NASA Astrophysics Data System (ADS)

    Turcotte, Caroline S.; Puckrin, Eldon; Aube, Françoys; Farley, Vincent; Savary, Simon; Chamberland, Martin

    2013-05-01

    High resolution broad-band imagery in the visible and infrared bands provides valuable detection capabilities based on target shapes and temperatures. However, the spectral resolution provided by a hyperspectral imager adds a spectral dimension to the measurements, which leads to an additional means of detecting and identifying targets based on their spectral signature. The Telops Hyper-Cam sensor is an interferometer-based imaging system that enables the spatial and spectral analysis of targets using a single sensor. It is based on the Fourier-transform technology, which yields high spectral resolution and enables a high accuracy radiometric calibration. It provides datacubes of up to 320×256 pixels at spectral resolutions as fine as 0.25 cm-1. The LWIR version covers the 8.0 to 11.8 μm spectral range. The Hyper-Cam has been recently integrated and flown on a novel airborne gyro-stabilized platform inside a fixed-wing aircraft. The new platform, more compact and more advanced than its predecessor, is described in this paper. The first results of target detection and identification are also presented.

  17. Airborne multispectral and hyperspectral remote sensing: Examples of applications to the study of environmental and engineering problems

    SciTech Connect

    Bianchi, R.; Marino, C.M.

    1997-10-01

    The availability of a new aerial survey capability carried out by the CNR/LARA (National Research Council - Airborne Laboratory for the Environmental Research) by a new spectroradiometer AA5000 MIVIS (Multispectral Infrared and Visible Imaging Spectrometer) on board a CASA 212/200 aircraft, enable the scientists to obtain innovative data sets, for different approach to the definitions and the understanding of a variety of environmental and engineering problems. The 102 MIVIS channels spectral bandwidths are chosen to meet the needs of scientific research for advanced applications of remote sensing data. In such configuration MIVIS can offer significant contributions to problem solving in wide sectors such as geologic exploration, agricultural crop studies, forestry, land use mapping, idrogeology, oceanography and others. LARA in 1994-96 has been active over different test-sites in joint-venture with JPL, Pasadena, different European Institutions and Italian University and Research Institutes. These aerial surveys allow the national and international scientific community to approach the use of Hyperspectral Remote Sensing in environmental problems of very large interest. The sites surveyed in Italy, France and Germany include a variety of targets such as quarries, landfills, karst cavities areas, landslides, coastlines, geothermal areas, etc. The deployments gathered up to now more than 300 GBytes of MIVIS data in more than 30 hours of VLDS data recording. The purpose of this work is to present and to comment the procedures and the results at research and at operational level of the past campaigns with special reference to the study of environmental and engineering problems.

  18. Analysis of Vegetation Within A Semi-Arid Urban Environment Using High Spatial Resolution Airborne Thermal Infrared Remote Sensing Data

    NASA Technical Reports Server (NTRS)

    Quattrochi, Dale A.; Ridd, Merrill K.

    1998-01-01

    High spatial resolution (5 m) remote sensing data obtained using the airborne Thermal Infrared Multispectral Scanner (TIMS) sensor for daytime and nighttime have been used to measure thermal energy responses for 2 broad classes and 10 subclasses of vegetation typical of the Salt Lake City, Utah urban landscape. Polygons representing discrete areas corresponding to the 10 subclasses of vegetation types have been delineated from the remote sensing data and are used for analysis of upwelling thermal energy for day, night, and the change in response between day and night or flux, as measured by the TIMS. These data have been used to produce three-dimensional graphs of energy responses in W/ sq m for day, night, and flux, for each urban vegetation land cover as measured by each of the six channels of the TIMS sensor. Analysis of these graphs provides a unique perspective for both viewing and understanding thermal responses, as recorded by the TIMS, for selected vegetation types common to Salt Lake City. A descriptive interpretation is given for each of the day, night, and flux graphs along with an analysis of what the patterns mean in reference to the thermal properties of the vegetation types surveyed in this study. From analyses of these graphs, it is apparent that thermal responses for vegetation can be highly varied as a function of the biophysical properties of the vegetation itself, as well as other factors. Moreover, it is also seen where vegetation, particularly trees, has a significant influence on damping or mitigating the amount of thermal radiation upwelling into the atmosphere across the Salt Lake City urban landscape. Published by Elsevier Science Ltd.

  19. Passive remote sensing of large-scale methane emissions from Oil Fields in California's San Joaquin Valley and validation by airborne in-situ measurements - Results from COMEX

    NASA Astrophysics Data System (ADS)

    Gerilowski, Konstantin; Krautwurst, Sven; Thompson, David R.; Thorpe, Andrew K.; Kolyer, Richard W.; Jonsson, Haflidi; Krings, Thomas; Frankenberg, Christian; Horstjann, Markus; Leifer, Ira; Eastwood, Michael; Green, Robert O.; Vigil, Sam; Fladeland, Matthew; Schüttemeyer, Dirk; Burrows, John P.; Bovensmann, Heinrich

    2016-04-01

    The CO2 and MEthane EXperiment (COMEX) was a NASA and ESA funded campaign in support of the HyspIRI and CarbonSat mission definition activities. As a part of this effort, seven flights were performed between June 3 and September 4, 2014 with the Methane Airborne MAPper (MAMAP) remote sensing instrument (operated by the University of Bremen in cooperation with the German Research Centre for Geosciences - GFZ) over the Kern River, Kern Front, and Poso Creek Oil Fields located in California's San Joaquin Valley. MAMAP was installed for the flights aboard the Center for Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS) Twin Otter aircraft, together with: a Picarro fast in-situ greenhouse gas (GHG) analyzer operated by the NASA Ames Research Center, ARC; a 5-hole turbulence probe; and an atmospheric measurement package operated by CIRPAS measuring aerosols, temperature, dew-point, and other atmospheric parameters. Three of the flights were accompanied by the Next Generation Airborne Visual InfraRed Imaging Spectrometer (AVIRIS-NG), operated by the Jet Propulsion Laboratory (JPL), California Institute of Technology, installed aboard a second Twin Otter aircraft. Large-scale, high-concentration CH4 plumes were detected by the MAMAP instrument over the fields and tracked over several kilometers. The spatial distribution of the MAMAP observed plumes was compared to high spatial resolution CH4 anomaly maps derived by AVIRIS-NG imaging spectroscopy data. Remote sensing data collected by MAMAP was used to infer CH4 emission rates and their distributions over the three fields. Aggregated emission estimates for the three fields were compared to aggregated emissions inferred by subsequent airborne in-situ validation measurements collected by the Picarro instrument. Comparison of remote sensing and in-situ flux estimates will be presented, demonstrating the ability of airborne remote sensing data to provide accurate emission estimates for concentrations above the

  20. Airborne in situ vertical profiling of HDO / H216O in the subtropical troposphere during the MUSICA remote sensing validation campaign

    NASA Astrophysics Data System (ADS)

    Dyroff, C.; Sanati, S.; Christner, E.; Zahn, A.; Balzer, M.; Bouquet, H.; McManus, J. B.; Gonzalez-Ramos, Y.; Schneider, M.

    2015-05-01

    Vertical profiles of water vapor (H2O) and its isotope ratio D / H expressed as δD(H2O) were measured in situ by the ISOWAT II diode-laser spectrometer during the MUlti-platform remote Sensing of Isotopologues for investigating the Cycle of Atmospheric water (MUSICA) airborne campaign. We present recent modifications of the instrument design. The instrument calibration on the ground as well as in flight is described. Based on the calibration measurements, the humidity-dependent uncertainty of our airborne data is determined. For the majority of the airborne data we achieved an accuracy (uncertainty of the mean) of Δ(δD) ≈10‰. Vertical profiles between 150 and ~7000 m were obtained during 7 days in July and August 2013 over the subtropical North Atlantic Ocean near Tenerife. The flights were coordinated with ground-based (Network for the Detection of Atmospheric Composition Change, NDACC) and space-based (Infrared Atmospheric Sounding Interferometer, IASI) FTIR remote sensing measurements of δD(H2O) as a means to validate the remote sensing humidity and δD(H2O) data products. The results of the validation are presented in detail in a separate paper (Schneider et al., 2014). The profiles were obtained with a high vertical resolution of around 3 m. By analyzing humidity and δD(H2O) correlations we were able to identify different layers of air masses with specific isotopic signatures. The results are discussed.

  1. Airborne in situ vertical profiling of HDO/H216O in the subtropical troposphere during the MUSICA remote sensing validation campaign

    NASA Astrophysics Data System (ADS)

    Dyroff, C.; Sanati, S.; Christner, E.; Zahn, A.; Balzer, M.; Bouquet, H.; McManus, J. B.; González-Ramos, Y.; Schneider, M.

    2015-01-01

    Vertical profiles of water vapor (H2O) and its isotope ratio D / H expressed as δ D(H2O were measured in situ by the ISOWAT II diode-laser spectrometer during the MUlti-platform remote Sensing of Isotopologues for investigating the Cycle of Atmospheric water (MUSICA) airborne campaign. We present recent modifications of the instrument design. The instrument calibration on the ground as well as in flight is described. Based on the calibration measurements, the humidity-dependent uncertainty of our airborne data is determined. For the majority of the airborne data we achieved an accuracy (uncertainty of the mean) of Δ(δ D) ≈ 10‰. Vertical profiles between 150 and ~7000 m were obtained during 7 days in July and August 2013 over the subtropical North Atlantic Ocean near Tenerife. The flights were coordinated with ground-based (Network for the Detection of Atmospheric Composition Change, NDACC) and space-based (Infrared Atmospheric Sounding Interferometer, IASI) FTIR remote-sensing measurements of δ D(H2O) as a means to validate the remote sensing humidity and δ D(H2O) data products. The results of the validation are presented in detail in a separate paper (Schneider et al., 2014). The profiles were obtained with a high vertical resolution of around 3 m. By analyzing humidity and δ D(H2O) correlations we were able to identify different layers of airmasses with specific isotopic signatures. The results are discussed.

  2. Remote sensing measurements of the CO2 mixing ratio in the planetary boundary layer using cloud slicing with airborne lidar

    NASA Astrophysics Data System (ADS)

    Ramanathan, Anand K.; Mao, Jianping; Abshire, James B.; Allan, Graham R.

    2015-03-01

    We have measured the CO2 volume mixing ratio (VMR) within the planetary boundary layer (PBL) using cloud slicing with an airborne pulsed integrated path differential absorption (IPDA) lidar from flight altitudes of up to 13 km. During a flight over Iowa in summer 2011, simultaneous measurement of the optical range and CO2 absorption to clouds and the ground were made using time-resolved detection of pulse echoes from each scattering surface. We determined the CO2 absorption in the PBL by differencing the two lidar-measured absorption line shapes, one to a broken shallow cumulus cloud layer located at the top of the PBL and the other to the ground. Solving for the CO2 VMR in the PBL and that of the free troposphere, we measured a ≈15 ppm (4%) drawdown in the PBL. Both CO2 VMRs were within ≈3 ppm of in situ CO2 profile measurements. We have also demonstrated cloud slicing using scatter from thin, diffuse cirrus clouds and cumulus clouds, which allowed solving for the CO2 VMR for three vertical layers. The technique and retrieval algorithm are applicable to a space-based lidar instrument as well as to lidar IPDA measurements of other trace gases. Thus, lidar cloud slicing also offers promise toward space-based remote sensing of vertical trace gas profiles in the atmosphere using a variety of clouds.

  3. Airborne remote sensing of photosynthetic light use efficiency and carbon uptake along an Arctic transect in Finland

    NASA Astrophysics Data System (ADS)

    Atherton, J.; Hill, T. C.; Prieto-Blanco, A.; Wade, T.; Clement, R.; Moncrieff, J.; Williams, M. D.; Disney, M.; Nichol, C. J.

    2009-12-01

    It is critical to understand the dynamics of ecosystem carbon uptake through seasonal changes and in response to environmental drivers. In this study we utilised aircraft based remote sensing and CO2/H2O flux monitoring systems to quantify changes in photosynthesis along an Arctic transect. The University of Edinburgh's (UK) research aircraft (a Diamond HK 36 TTC-ECO Dimona) was deployed in the Arctic during summer 2008 to carry out a series of transect-flights over a birch-mire mosaic site near Kevo, Finland as part of the Arctic Biosphere Atmosphere Coupling at Multiple Scales (ABACUS) project. The aircraft is equipped with automated dual field-of-view (hyperspectral) radiometers and CO2/H2O flux and meteorological instrumentation. Vegetation indices known to be related to photosynthetic light use efficiency (LUE), including the well established Photochemical Reflectance Index (PRI) and Solar-induced Fluorescence (SiF) as well as the Normalized Difference Vegetation Index (NDVI) were calculated from the spectral data and matched in space to the CO2 flux measurements. We explored spatial relationships between NDVI and CO2 flux, LUE (CO2 flux / Absorbed Photosynthetically Active Radiation) and PRI and finally SiF (calculated using the Fraunhofer infilling method) and relevant environmental drivers. Our results highlight the unique ability of an airborne platform to quantify ecosystem physiology across a landscape and demonstrate how such measurements can bridge the spatial gap between ground and satellite-based observations.

  4. Analysis of potential debris flow source areas on Mount Shasta, California, by using airborne and satellite remote sensing data

    USGS Publications Warehouse

    Crowley, J.K.; Hubbard, B.E.; Mars, J.C.

    2003-01-01

    Remote sensing data from NASA's Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) and the first spaceborne imaging spectrometer, Hyperion, show hydrothermally altered rocks mainly composed of natroalunite, kaolinite, cristobalite, and gypsum on both the Mount Shasta and Shastina cones. Field observations indicate that much of the visible altered rock consists of talus material derived from fractured rock zones within and adjacent to dacitic domes and nearby lava flows. Digital elevation data were utilized to distinguish steeply sloping altered bedrock from more gently sloping talus materials. Volume modeling based on the imagery and digital elevation data indicate that Mount Shasta drainage systems contain moderate volumes of altered rock, a result that is consistent with Mount Shasta's Holocene record of mostly small to moderate debris flows. Similar modeling for selected areas at Mount Rainier and Mount Adams, Washington, indicates larger altered rock volumes consistent with the occurrence of much larger Holocene debris flows at those volcanoes. The availability of digital elevation and spectral data from spaceborne sensors, such as Hyperion and the Advanced Spaceborne Thermal Emission and Reflectance Radiometer (ASTER), greatly expands opportunities for studying potential debris flow source characteristics at stratovolcanoes around the world. ?? 2003 Elsevier Inc. All rights reserved.

  5. Passive Microwave Remote Sensing of Falling Snow and Associated GPM Field Campaigns

    NASA Technical Reports Server (NTRS)

    Skofronick-Jackson, Gail

    2011-01-01

    Retrievals of falling snow from space represent one of the next important challenges for the atmospheric, hydrological, and energy budget scientific communities. Historically, retrievals of falling snow have been difficult due to the relative insensitivity of satellite rain-based channels as used in the past. We emphasize the use of high frequency passive microwave channels (85-200 GHz) since these are more sensitive to the ice in clouds and have been used to estimate falling snow from space. While satellite-based remote sensing provides global coverage of falling snow events and the science is relatively new, retrievals are still undergoing development with challenges remaining. There are several current satellite sensors, though not specifically designed for estimating falling snow, are capable of measuring snow from space. These include NOAA's AMSU-B, the MHS sensors, and CloudSat radar. They use high frequency (greater than 85 GHz) passive and active microwave and millimeter-wave channels that are sensitive to the scattering from ice and snow particles in the atmosphere. Sensors with water vapor channels near 183 GHz center line provide opaqueness to the Earth's surface features that can contaminate the falling snow signatures, especially over snow covered surface. In addition, the Global Precipitation Measurement (GPM) mission scheduled for launch in 2013 is specifically designed to measure both liquid rain and frozen snow precipitation. Since falling snow from space is the next precipitation measurement challenge from space, information must be determined in order to guide retrieval algorithm development for these current and future missions. This information includes thresholds of detection for various sensor channel configurations, snow event system characteristics, and surface types. For example, can a lake effect snow system with low cloud tops having an ice water content (IWC) at the surface of 1.0 gram per cubic meter be detected? If this information is

  6. Assessing stream temperature variation in the Pacific Northwest using airborne thermal infrared remote sensing.

    PubMed

    Tan, Jing; Cherkauer, Keith A

    2013-01-30

    The objective of this paper is to evaluate the temporal and spatial variability of stream temperatures and how stream temperatures are affected by land use through the use of airborne thermal infrared (TIR) imagery. Both five-meter and fifteen-meter MODIS/ASTER (MASTER) imagery were acquired along the main channel of the Green-Duwamish River in Washington State, U.S. in multiple straight line passes with image overlaps occurring at time intervals of between 3 and 45 min. Five- and fifteen-meter data were collected on August 25th, 2001, with a few additional five-meter images collected on August 27th. Image overlaps were studied to evaluate the time dependence between acquisition time and observed water temperature. Temperature change between adjacent images over the course of a few minutes was found to be negligible, but became significant at times greater than 45 min, with an estimated increase in water temperature of 2-3 °C between the first and last image collected for the complete five-meter resolution survey. Images captured from different days help identify persistent localized temperature differences. While accounting for temperature changes that occurred during the acquisition process, we still found that average stream reach temperatures increased with urbanization, while variability decreased. The same occurred in the immediate presence of a reservoir. This study suggests that urbanization affects stream temperature not only through the removal of riparian zone vegetation, but also through changes to sources in in-stream variability including the presence of rocks, woody debris and sandbars.

  7. Using Google Earth for Rapid Dissemination of Airborne Remote Sensing Lidar and Photography

    NASA Astrophysics Data System (ADS)

    Wright, C. W.; Nayegandhi, A.; Brock, J. C.

    2006-12-01

    In order to visualize and disseminate vast amounts of lidar and digital photography data, we present a unique method that make these data layers available via the Google Earth interface. The NASA Experimental Advanced Airborne Research Lidar (EAARL) provides unprecedented capabilities to survey coral reefs, nearshore benthic habitats, coastal vegetation, and sandy beaches. The EAARL sensor suite includes a water-penetrating lidar that provides high-resolution topographic information, a down-looking color digital camera, a down-looking high-resolution color-infrared (CIR) digital camera, and precision kinematic GPS receivers which provide for sub-meter geo-referencing of each laser and multispectral sample. Google Earth "kml" files are created for each EAARL multispectral and processed lidar image. A hierarchical structure of network links allows the user to download high-resolution images within the region of interest. The first network link (kmz file) downloaded by the user contains a color coded flight path and "minute marker" icons along the flight path. Each "minute" icon provides access to the image overlays, and additional network links for each second along the flight path as well as flight navigation information. Layers of false-color-coded lidar Digital Elevation Model (DEM) data are made available in 2 km by 2km tiles. These layers include canopy-top, bare-Earth, submerged topography, and links to any other lidar products. The user has the option to download the x,y,z ascii point data or a DEM in the Geotif file format for each tile. The NASA EAARL project captured roughly 250,000 digital photographs in five flights conducted a few days after Hurricane Katrina made landfall along the Gulf Coast in 2005. All of the photos and DEM layers are georeferenced and viewable online using Google Earth.

  8. Active remote sensing of snow using NMM3D/DMRT and comparison with CLPX II airborne data

    USGS Publications Warehouse

    Xu, X.; Liang, D.; Tsang, L.; Andreadis, K.M.; Josberger, E.G.; Lettenmaier, D.P.; Cline, D.W.; Yueh, S.H.

    2010-01-01

    We applied the Numerical Maxwell Model of three-dimensional simulations (NMM3D) in the Dense Media Radiative Theory (DMRT) to calculate backscattering coefficients. The particles' positions are computer-generated and the subsequent Foldy-Lax equations solved numerically. The phase matrix in NMM3D has significant cross-polarization, particularly when the particles are densely packed. The NMM3D model is combined with DMRT in calculating the microwave scattering by dry snow. The NMM3D/DMRT equations are solved by an iterative solution up to the second order in the case of small to moderate optical thickness. The numerical results of NMM3D/DMRT are illustrated and compared with QCA/DMRT. The QCA/DMRT and NMM3D/DMRT results are also applied to compare with data from two specific datasets from the second Cold Land Processes Experiment (CLPX II) in Alaska and Colorado. The data are obtained at the Ku-band (13.95 GHz) observations using airborne imaging polarimetric scatterometer (POLSCAT). It is shown that the model predictions agree with the field measurements for both co-polarization and cross-polarization. For the Alaska region, the average snow depth and snow density are used as the inputs for DMRT. The grain size, selected from within the range of the ground measurements, is used as a best-fit parameter within the range. For the Colorado region, we use the Variable Infiltration Capacity Model (VIC) to obtain the input snow profiles for NMM3D/DMRT. ?? 2010 IEEE.

  9. Airborne retrieval of cirrus cloud optical and microphysical properties using Airborne Remote Earth Sensing System 5.1-5.3 and 3.7-μm channel data

    NASA Astrophysics Data System (ADS)

    Ou, S. C.; Liou, K. N.; Yang, P.; Rolland, P.; Caudill, T. R.; Lisowski, J.; Morrison, B.

    1998-09-01

    We present an airborne retrieval algorithm to infer cirrus cloud temperature, optical depth, and mean effective sizes using the Airborne Remote Earth Sensing System (ARES) hyperspectral spectrometer data for the 5.1-5.3 and 3.7 μm channels. The algorithm, development and the selection of the channels are based on the principle and parameterization of radiative transfer involving cirrus clouds and the associated atmospheric and surface properties. It has been applied to a selected case of the ARES data collected over the western Boston area on September 16, 1995. Validation of the retrieved parameters was carried out using the collocated and coincident ground-based 8.6-mm radar data and ice crystal size distribution measurements obtained from the 2D-P probe on board the high-altitude reconnaissance platform (HARP). We show that the retrieved cirrus cloud temperature, mean effective ice crystal size, and optical depth match closely with those derived from the observations.

  10. Tracking Snowmelt Events in Remote High Asia Using Passive Microwave Data

    NASA Astrophysics Data System (ADS)

    Smith, T.; Bookhagen, B.

    2015-12-01

    While snowfall can comprise a significant percentage of the yearly water budget in High Asia, Snow-Water Equivalent (SWE) is poorly constrained due to lack of in-situ measurements and complex terrain that limits the efficacy of modeling and observations. Over the past few decades, SWE has been estimated with the SSMI/S and AMSR passive microwave (PM) sensors, with low reliability in High Asia. Despite problematic SWE volume estimation, PM data contains information on the buildup and melt of snowpack, which is difficult to measure in-situ, particularly in remote areas. We present a new methodology for tracking the timing, frequency, and relative intensity of melt events across High Asia. To measure SWE, we use raw swath data from the SSMI/S (1987-2015, F08, F11, F13, F17), AMSR (2002-2011), and GPM (2014-2015) satellites. This allows us to improve both spatial and temporal resolution over daily gridded products by leveraging multiple overpasses per day in an imperfectly overlapping grid pattern. We then examine SWE estimates, intra-day PM variance, and the interacting impacts of satellite look angles and topography on measured PM at arbitrary point locations. We develop a more thorough understanding of the uncertainties in our SWE estimates by examining the impacts of aspect, relief, slope, and elevation across the Tibetan Plateau on Tb and SWE estimates. High Asia, with its large topographic gradients and low relief at high elevations provides an excellent context to examine a wide range of topographic settings and terrain complexities to better constrain our analysis of sensor bias. We find that slopes above ~10° have a strong impact on SWE variability. We also find a consistent intra- and inter-day variability within constant-SWE periods, as defined as periods without precipitation and with constant temperatures below 0°C. Using this measure of native sensor variability, we filter our SWE time series to identify events of snowmelt which are outside of the

  11. Using remote sensing and ancillary data to extend airborne electromagnetic resistivity surveys for regional permafrost interpretation

    NASA Astrophysics Data System (ADS)

    Pastick, N.; Wylie, B. K.; Minsley, B. J.; Jorgenson, T. T.; Ji, L.; Walvoord, M. A.; Smith, B. D.; Abraham, J. D.; Rose, J.

    2011-12-01

    Permafrost has a significant impact on high latitude ecosystems and is spatially heterogeneous. However, only generalized maps of permafrost extent are available. Due to its impacts on subsurface hydrology, lake water levels, vegetation communities, and surface soil deformations, understanding the spatial extents and depth of permafrost are critical. Electrical resistivity increases dramatically as a soil freezes and can be used as a proxy for permafrost presence particularly if the underlying soils and geologic characteristics are understood. An airborne electromagnetic survey (AEM) was conducted over a portion of the Yukon Flats ecoregion in central Alaska with measurements taken in both reconnaissance lines and contiguous block area coverage. The AEM was flown in June 2010 and subsurface resistivity models were derived by inverting the AEM data. Landsat TM at-sensor reflectance, thermal, and spectral index data from late August to early September 2008, Digital Elevation Models (DEM) and derivatives, and other ancillary data were used in a regression tree model to predict near surface electrical resistivity at the 0-1m and the 0-2.6m depth intervals. AEM locations from homogenous landsat 90 m by 90 m windows were randomly separated into a training set for model development (n = 8,848) and an impendent test data set (n = 988) for model accuracy assessment. Model development and independent test accuracies for 0-1 m electric resistivity had training and test R2 values of 0.90 and 0.87, respectively, and for the 0-2.6m electric resistivity training and test R2 values were also 0.90 and 0.87, respectively, which indicated accurate prediction models. Important variables for stratifying the various piecewise regressions were elevation and averaged 2000-2008 ecosystem performance anomalies. Important independent variables used in the multiple regression equations were the Normalized Difference Infrared Index (NDII), NDII7 (NDII using band 7), soil moisture mapped from

  12. Atmospheric profiles of Black Carbon at remote locations using light-weight airborne Aethalometers

    NASA Astrophysics Data System (ADS)

    Hansen, A. D.; Močnik, G.; Drinovec, L.; Lenarcic, M.

    2012-12-01

    While measurements of atmospheric aerosols are routinely performed at ground-level around the world, there is far less knowledge of their concentrations at altitude: yet this data is a crucial requirement for our understanding of the dispersion of pollutants of anthropogenic origin, with their associated effects on radiative forcing, cloud condensation, and other adverse phenomena. Black Carbon (BC) is a unique tracer for combustion emissions, and can be detected rapidly and with great sensitivity by filter-based optical methods. It has no non-combustion sources and is not transformed by atmospheric processes. Recent technical advances have developed light-weight miniaturized instruments which can be operated on light aircraft or carried aboard commercial passenger flights. From January to April 2012, a single-seat ultra-light aircraft flew around the world on a scientific, photographic and environmental-awareness mission. The flight track crossed all seven continents and all major oceans, with altitudes up to 8.9 km ASL. The aircraft carried a custom-developed high-sensitivity dual-wavelength light-weight Aethalometer, operating at 370 and 880 nm with special provision to compensate for the effects of changing pressure, temperature and humidity. The instrument recorded BC concentrations with high temporal resolution and sensitivity better than 5 ng/m3. We present examples of data from flight tracks over remote oceans, uninhabited land masses, and densely populated areas, analyzing the spectral dependence of absorption to infer the contributions to BC from fossil fuel vs. biomass combustion, and aggregating the data into vertical profiles. The regional and long range transport of BC may be investigated using back-trajectories. We have also operated miniature instruments in the passenger cabins of long-distance commercial aircraft. Since there are no combustion sources within the cabin, any BC in the ventilation air must necessarily have originated from the outside

  13. Remote sensing of ocean pollution. (Latest citations from the Aerospace database). Published Search

    SciTech Connect

    1995-02-01

    The bibliography contains citations concerning the use of remote sensing for the control and monitoring of ocean pollution. Citations discuss remote sensing techniques and instrumentations, including airborne and satellite-borne photography, microwave radiometry, laser fluorescence, and radar imagery. Topics include oil spills, marine ecosystems, land-based pollutants, ocean dumping, remote sensing capability and reliability, and pollution transport. (Contains a minimum of 109 citations and includes a subject term index and title list.)

  14. Airborne passive remote sensing of large-scale methane emissions from oil fields in California's San Joaquin Valley and validation by airborne in-situ measurements - Initial results from COMEX

    NASA Astrophysics Data System (ADS)

    Gerilowski, Konstantin; Krautwurst, Sven; Kolyer, Richard W.; Thompson, David R.; Jonsson, Haflidi; Krings, Thomas; Horstjann, Markus; Leifer, Ira; Eastwood, Michael; Green, Robert O.; Vigil, Sam; Schüttemeyer, Dirk; Fladeland, Matthew; Burrows, John P.; Bovensmann, Heinrich

    2015-04-01

    On several flights performed over the Kern River, Kern Front, and Poso Creek Oil Fields in California between June 3 and September 4, 2014, in the framework of the CO2 and MEthane Experiment (COMEX) - a NASA and ESA funded campaign in support of the HyspIRI and CarbonSat mission definition activities - the Methane Airborne MAPper (MAMAP) remote sensing instrument (operated by the University of Bremen in cooperation with the German Research Centre for Geosciences - GFZ) detected large-scale, high-concentration, methane plumes. MAMAP was installed for the flights aboard the Center for Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS) Twin Otter aircraft, together with a Picarro fast in-situ greenhouse gas (GHG) analyzer (operated by the NASA Ames Research Center, ARC), a 5-hole turbulence probe and an atmospheric measurement package (operated by CIRPAS), measuring aerosols, temperature, dew-point, and other atmospheric parameters. Some of the flights were accompanied by the next generation of the Airborne Visible InfraRed Imaging Spectrometer (AVIRIS-NG), operated by the Jet Propulsion Laboratory (JPL), California Institute of Technology, installed aboard a second Twin Otter aircraft (operated by Twin Otter International). Data collected with the in-situ GHG analyzer were used for validation of the MAMAP and AVIRIS-NG remotely sensed data. The in-situ measurements were acquired in vertical cross sections of the discovered plumes at fixed distances downwind of the sources. Emission rates are estimated from both the remote and in-situ data using wind information from the turbulence probe together with ground-based wind data from the nearby airport. Remote sensing and in-situ data as well as initial flux estimates for selected flights will be presented.

  15. Visibility through the gaseous smoke in airborne remote sensing using a DSLR camera

    NASA Astrophysics Data System (ADS)

    Chabok, Mirahmad; Millington, Andrew; Hacker, Jorg M.; McGrath, Andrew J.

    2016-08-01

    Visibility and clarity of remotely sensed images acquired by consumer grade DSLR cameras, mounted on an unmanned aerial vehicle or a manned aircraft, are critical factors in obtaining accurate and detailed information from any area of interest. The presence of substantial haze, fog or gaseous smoke particles; caused, for example, by an active bushfire at the time of data capture, will dramatically reduce image visibility and quality. Although most modern hyperspectral imaging sensors are capable of capturing a large number of narrow range bands of the shortwave and thermal infrared spectral range, which have the potential to penetrate smoke and haze, the resulting images do not contain sufficient spatial detail to enable locating important objects or assist search and rescue or similar applications which require high resolution information. We introduce a new method for penetrating gaseous smoke without compromising spatial resolution using a single modified DSLR camera in conjunction with image processing techniques which effectively improves the visibility of objects in the captured images. This is achieved by modifying a DSLR camera and adding a custom optical filter to enable it to capture wavelengths from 480-1200nm (R, G and Near Infrared) instead of the standard RGB bands (400-700nm). With this modified camera mounted on an aircraft, images were acquired over an area polluted by gaseous smoke from an active bushfire. Processed data using our proposed method shows significant visibility improvements compared with other existing solutions.

  16. Spaceborne Microwave Instrument for High Resolution Remote Sensing of the Earth's Surface Using a Large-Aperture Mesh Antenna

    NASA Technical Reports Server (NTRS)

    Njoku, E.; Wilson, W.; Yueh, S.; Freeland, R.; Helms, R.; Edelstein, W.; Sadowy, G.; Farra, D.; West, R.; Oxnevad, K.

    2001-01-01

    This report describes a two-year study of a large-aperture, lightweight, deployable mesh antenna system for radiometer and radar remote sensing of the Earth from space. The study focused specifically on an instrument to measure ocean salinity and Soil moisture. Measurements of ocean salinity and soil moisture are of critical . importance in improving knowledge and prediction of key ocean and land surface processes, but are not currently obtainable from space. A mission using this instrument would be the first demonstration of deployable mesh antenna technology for remote sensing and could lead to potential applications in other remote sensing disciplines that require high spatial resolution measurements. The study concept features a rotating 6-m-diameter deployable mesh antenna, with radiometer and radar sensors, to measure microwave emission and backscatter from the Earth's surface. The sensors operate at L and S bands, with multiple polarizations and a constant look angle, scanning across a wide swath. The study included detailed analyses of science requirements, reflector and feedhorn design and performance, microwave emissivity measurements of mesh samples, design and test of lightweight radar electronic., launch vehicle accommodations, rotational dynamics simulations, and an analysis of attitude control issues associated with the antenna and spacecraft, The goal of the study was to advance the technology readiness of the overall concept to a level appropriate for an Earth science emission.

  17. Foreword to the Special Issue on the 11th Specialist Meeting on Microwave Radiometry and Remote Sensing Applications (MicroRad 2010)

    NASA Technical Reports Server (NTRS)

    Le Vine, David M; Jackson, Thomas J.; Kim, Edward J.; Lang, Roger H.

    2011-01-01

    The Specialist Meeting on Microwave Radiometry and Remote Sensing of the Environment (MicroRad 2010) was held in Washington, DC from March 1 to 4, 2010. The objective of MicroRad 2010 was to provide an open forum to report and discuss recent advances in the field of microwave radiometry, particularly with application to remote sensing of the environment. The meeting was highly successful, with more than 200 registrations representing 48 countries. There were 80 oral presentations and more than 100 posters. MicroRad has become a venue for the microwave radiometry community to present new research results, instrument designs, and applications to an audience that is conversant in these issues. The meeting was divided into 16 sessions (listed in order of presentation): 1) SMOS Mission; 2) Future Passive Microwave Remote Sensing Missions; 3) Theory and Physical Principles of Electromagnetic Models; 4) Field Experiment Results; 5) Soil Moisture and Vegetation; 6) Snow and Cryosphere; 7) Passive/Active Microwave Remote Sensing Synergy; 8) Oceans; 9) Atmospheric Sounding and Assimilation; 10) Clouds and Precipitation; 11) Instruments and Advanced Techniques I; 12) Instruments and Advanced Techniques II; 13) Cross Calibration of Satellite Radiometers; 14) Calibration Theory and Methodology; 15) New Technologies for Microwave Radiometry; 16) Radio Frequency Interference.

  18. Acute health impacts of airborne particles estimated from satellite remote sensing.

    PubMed

    Wang, Zhaoxi; Liu, Yang; Hu, Mu; Pan, Xiaochuan; Shi, Jing; Chen, Feng; He, Kebin; Koutrakis, Petros; Christiani, David C

    2013-01-01

    Satellite-based remote sensing provides a unique opportunity to monitor air quality from space at global, continental, national and regional scales. Most current research focused on developing empirical models using ground measurements of the ambient particulate. However, the application of satellite-based exposure assessment in environmental health is still limited, especially for acute effects, because the development of satellite PM(2.5) model depends on the availability of ground measurements. We tested the hypothesis that MODIS AOD (aerosol optical depth) exposure estimates, obtained from NASA satellites, are directly associated with daily health outcomes. Three independent healthcare databases were used: unscheduled outpatient visits, hospital admissions, and mortality collected in Beijing metropolitan area, China during 2006. We use generalized linear models to compare the short-term effects of air pollution assessed by ground monitoring (PM(10)) with adjustment of absolute humidity (AH) and AH-calibrated AOD. Across all databases we found that both AH-calibrated AOD and PM(10) (adjusted by AH) were consistently associated with elevated daily events on the current day and/or lag days for cardiovascular diseases, ischemic heart diseases, and COPD. The relative risks estimated by AH-calibrated AOD and PM(10) (adjusted by AH) were similar. Additionally, compared to ground PM(10), we found that AH-calibrated AOD had narrower confidence intervals for all models and was more robust in estimating the current day and lag day effects. Our preliminary findings suggested that, with proper adjustment of meteorological factors, satellite AOD can be used directly to estimate the acute health impacts of ambient particles without prior calibrating to the sparse ground monitoring networks. PMID:23220016

  19. Acute health impacts of airborne particles estimated from satellite remote sensing✩

    PubMed Central

    Wang, Zhaoxi; Liu, Yang; Hu, Mu; Pan, Xiaochuan; Shi, Jing; Chen, Feng; He, Kebin; Koutrakis, Petros; Christiani, David C.

    2013-01-01

    Satellite-based remote sensing provides a unique opportunity to monitor air quality from space at global, continental, national and regional scales. Most current research focused on developing empirical models using ground measurements of the ambient particulate. However, the application of satellite-based exposure assessment in environmental health is still limited, especially for acute effects, because the development of satellite PM2.5 model depends on the availability of ground measurements. We tested the hypothesis that MODIS AOD (aerosol optical depth) exposure estimates, obtained from NASA satellites, are directly associated with daily health outcomes. Three independent healthcare databases were used: unscheduled outpatient visits, hospital admissions, and mortality collected in Beijing metropolitan area, China during 2006. We use generalized linear models to compare the short-term effects of air pollution assessed by ground monitoring (PM10) with adjustment of absolute humidity (AH) and AH-calibrated AOD. Across all databases we found that both AH-calibrated AOD and PM10 (adjusted by AH) were consistently associated with elevated daily events on the current day and/or lag days for cardiovascular diseases, ischemic heart diseases, and COPD. The relative risks estimated by AH-calibrated AOD and PM10 (adjusted by AH) were similar. Additionally, compared to ground PM10, we found that AH-calibrated AOD had narrower confidence intervals for all models and was more robust in estimating the current day and lag day effects. Our preliminary findings suggested that, with proper adjustment of meteorological factors, satellite AOD can be used directly to estimate the acute health impacts of ambient particles without prior calibrating to the sparse ground monitoring networks. PMID:23220016

  20. Concept and integration of an on-line quasi-operational airborne hyperspectral remote sensing system

    NASA Astrophysics Data System (ADS)

    Schilling, Hendrik; Lenz, Andreas; Gross, Wolfgang; Perpeet, Dominik; Wuttke, Sebastian; Middelmann, Wolfgang

    2013-10-01

    Modern mission characteristics require the use of advanced imaging sensors in reconnaissance. In particular, high spatial and high spectral resolution imaging provides promising data for many tasks such as classification and detecting objects of military relevance, such as camouflaged units or improvised explosive devices (IEDs). Especially in asymmetric warfare with highly mobile forces, intelligence, surveillance and reconnaissance (ISR) needs to be available close to real-time. This demands the use of unmanned aerial vehicles (UAVs) in combination with downlink capability. The system described in this contribution is integrated in a wing pod for ease of installation and calibration. It is designed for the real-time acquisition and analysis of hyperspectral data. The main component is a Specim AISA Eagle II hyperspectral sensor, covering the visible and near-infrared (VNIR) spectral range with a spectral resolution up to 1.2 nm and 1024 pixel across track, leading to a ground sampling distance below 1 m at typical altitudes. The push broom characteristic of the hyperspectral sensor demands an inertial navigation system (INS) for rectification and georeferencing of the image data. Additional sensors are a high resolution RGB (HR-RGB) frame camera and a thermal imaging camera. For on-line application, the data is preselected, compressed and transmitted to the ground control station (GCS) by an existing system in a second wing pod. The final result after data processing in the GCS is a hyperspectral orthorectified GeoTIFF, which is filed in the ERDAS APOLLO geographical information system. APOLLO allows remote access to the data and offers web-based analysis tools. The system is quasi-operational and was successfully tested in May 2013 in Bremerhaven, Germany.

  1. Multi-resolution processing for fractal analysis of airborne remotely sensed data

    NASA Technical Reports Server (NTRS)

    Jaggi, S.; Quattrochi, D.; Lam, N.

    1992-01-01

    Fractal geometry is increasingly becoming a useful tool for modeling natural phenomenon. As an alternative to Euclidean concepts, fractals allow for a more accurate representation of the nature of complexity in natural boundaries and surfaces. Since they are characterized by self-similarity, an ideal fractal surface is scale-independent; i.e. at different scales a fractal surface looks the same. This is not exactly true for natural surfaces. When viewed at different spatial resolutions parts of natural surfaces look alike in a statistical manner and only for a limited range of scales. Images acquired by NASA's Thermal Infrared Multispectral Scanner are used to compute the fractal dimension as a function of spatial resolution. Three methods are used to determine the fractal dimension - Schelberg's line-divider method, the variogram method, and the triangular prism method. A description of these methods and the results of applying these methods to a remotely-sensed image is also presented. Five flights were flown in succession at altitudes of 2 km (low), 6 km (mid), 12 km (high), and then back again at 6 km and 2 km. The area selected was the Ross Barnett reservoir near Jackson, Mississippi. The mission was flown during the predawn hours of 1 Feb. 1992. Radiosonde data was collected for that duration to profile the characteristics of the atmosphere. This corresponds to 3 different pixel sizes - 5m, 15m, and 30m. After, simulating different spatial sampling intervals within the same image for each of the 3 image sets, the results are cross-correlated to compare the extent of detail and complexity that is obtained when data is taken at lower spatial intervals.

  2. Acute health impacts of airborne particles estimated from satellite remote sensing.

    PubMed

    Wang, Zhaoxi; Liu, Yang; Hu, Mu; Pan, Xiaochuan; Shi, Jing; Chen, Feng; He, Kebin; Koutrakis, Petros; Christiani, David C

    2013-01-01

    Satellite-based remote sensing provides a unique opportunity to monitor air quality from space at global, continental, national and regional scales. Most current research focused on developing empirical models using ground measurements of the ambient particulate. However, the application of satellite-based exposure assessment in environmental health is still limited, especially for acute effects, because the development of satellite PM(2.5) model depends on the availability of ground measurements. We tested the hypothesis that MODIS AOD (aerosol optical depth) exposure estimates, obtained from NASA satellites, are directly associated with daily health outcomes. Three independent healthcare databases were used: unscheduled outpatient visits, hospital admissions, and mortality collected in Beijing metropolitan area, China during 2006. We use generalized linear models to compare the short-term effects of air pollution assessed by ground monitoring (PM(10)) with adjustment of absolute humidity (AH) and AH-calibrated AOD. Across all databases we found that both AH-calibrated AOD and PM(10) (adjusted by AH) were consistently associated with elevated daily events on the current day and/or lag days for cardiovascular diseases, ischemic heart diseases, and COPD. The relative risks estimated by AH-calibrated AOD and PM(10) (adjusted by AH) were similar. Additionally, compared to ground PM(10), we found that AH-calibrated AOD had narrower confidence intervals for all models and was more robust in estimating the current day and lag day effects. Our preliminary findings suggested that, with proper adjustment of meteorological factors, satellite AOD can be used directly to estimate the acute health impacts of ambient particles without prior calibrating to the sparse ground monitoring networks.

  3. Husbandry Trace Gas Emissions from a Dairy Complex By Mobile in Situ and Airborne and Spaceborne Remote Sensing: A Comex Campaign Focus

    NASA Astrophysics Data System (ADS)

    Leifer, I.; Tratt, D. M.; Bovensmann, H.; Buckland, K. N.; Burrows, J. P.; Frash, J.; Gerilowski, K.; Iraci, L. T.; Johnson, P. D.; Kolyer, R.; Krautwurst, S.; Krings, T.; Leen, J. B.; Hu, C.; Melton, C.; Vigil, S. A.; Yates, E. L.; Zhang, M.

    2014-12-01

    Recent field study reviews on the greenhouse gas methane (CH4) found significant underestimation from fossil fuel industry and husbandry. The 2014 COMEX campaign seeks to develop methods to derive CH4 and carbon dioxide (CO2) from remote sensing data by combining hyperspectral imaging (HSI) and non-imaging spectroscopy (NIS) with in situ airborne and surface data. COMEX leverages synergies between high spatial resolution HSI column abundance maps and moderate spectral/spatial resolution NIS. Airborne husbandry data were collected for the Chino dairy complex (East Los Angeles Basin) by NIS-MAMAP, HSI-Mako thermal-infrared (TIR); AVIRIS NG shortwave IR (SWIR), with in situ surface mobile-AMOG Surveyor (AutoMObile greenhouse Gas)-and airborne in situ from a Twin Otter and the AlphaJet. AMOG Surveyor uses in situ Integrated Cavity Off Axis Spectroscopy (OA-ICOS) to measure CH4, CO2, H2O, H2S and NH3 at 5-10 Hz, 2D winds, and thermal anomaly in an adapted commuter car. OA-ICOS provides high precision and accuracy with excellent stability. NH3 and CH4 emissions were correlated at dairy size-scales but not sub-dairy scales in surface and Mako data, showing fine-scale structure and large variations between the numerous dairies in the complex (herd ~200,000-250,000) embedded in an urban setting. Emissions hotspots were consistent between surface and airborne surveys. In June, surface and MAMAP data showed a weak overall plume, while surface and Mako data showed a stronger plume in late (hotter) July. Multiple surface plume transects using NH3 fingerprinting showed East and then NE advection out of the LA Basin consistent with airborne data. Long-term trends were investigated in satellite data. This study shows the value of synergistically combined NH3 and CH4 remote sensing data to the task of CH4 source attribution using airborne and space-based remote sensing (IASI for NH3) and top of atmosphere sensitivity calculations for Sentinel V and Carbon Sat (CH4).

  4. Fusion of full waveform Laserscanning and airborne hyperspectral remote sensing data for the characterization of forest stands

    NASA Astrophysics Data System (ADS)

    Buddenbaum, Henning

    2010-05-01

    Hyperspectral data offer the maximum spectral reflectance information available from remote sensing. A continuous spectrum of narrow bands with near-laboratory quality is recorded for each pixel. This data can be used for difficult classification tasks or detailed quantitative analyses, e.g. determination of chlorophyll or water content in leaves. But in forested areas, discerning between different age classes of the same tree species is still error-prone. Airborne Laserscanning measures the three-dimensional position of every reflecting object and can be used to map tree heights and crown volumes. These are highly correlated with tree age and timber volume. In addition, Laserscanner data can be used to differentiate between coniferous and deciduous trees either by analysing crown shapes that lead to different surface roughness or by exploiting the intensity information of laser echoes from the crowns. But a more detailed determination of tree species is not possible using Laserscanning alone. The combination of hyperspectral and Laserscanning data promises the possibility to map both tree species and age classes. We used a HyMap data set with 122 bands recorded in 2003 and a full waveform Laserscanning recorded in 2005 in the same area, Idarwald Forest in South-western Germany. To combine both datasets, we defined voxels above the HyMap pixels, containing the mean laser intensity in slices of 50 cm height. These voxels form a second hyperspectral dataset of 76 bands with the same geometry as the HyMap image, so that they could be fused into a 198 band image. The joined image performed better in a classification of tree species and age classes than each of the single images and also better than a dataset consisting of the hyperspectral image and a tree height map. Apart from classification, it can also be used to derive tree heights and crown base heights and to estimate biomass, leaf area index and timber volume and to characterize the vertical forest structure.

  5. Identifying trout refuges in the Indian and Hudson Rivers in northern New York through airborne thermal infrared remote sensing

    USGS Publications Warehouse

    Ernst, Anne G.; Baldigo, Barry P.; Calef, Fred J.; Freehafer, Douglas A.; Kremens, Robert L.

    2015-10-09

    The locations and sizes of potential cold-water refuges for trout were examined in 2005 along a 27-kilometer segment of the Indian and Hudson Rivers in northern New York to evaluate the extent of refuges, the effects of routine flow releases from an impoundment, and how these refuges and releases might influence trout survival in reaches that otherwise would be thermally stressed. This river segment supports small populations of brook trout (Salvelinus fontinalis), brown trout (Salmo trutta), and rainbow trout (Oncorhynchus mykiss) and also receives regular releases of reservoir-surface waters to support rafting during the summer, when water temperatures in both the reservoir and the river frequently exceed thermal thresholds for trout survival. Airborne thermal infrared imaging was supplemented with continuous, in-stream temperature loggers to identify potential refuges that may be associated with tributary inflows or groundwater seeps and to define the extent to which the release flows decrease the size of existing refuges. In general, the release flows overwhelmed the refuge areas and greatly decreased the size and number of the areas. Mean water temperatures were unaffected by the releases, but small-scale heterogeneity was diminished. At a larger scale, water temperatures in the upper and lower segments of the reach were consistently warmer than in the middle segment, even during passage of release waters. The inability of remote thermal infrared images to consistently distinguish land from water (in shaded areas) and to detect groundwater seeps (away from the shallow edges of the stream) limited data analysis and the ability to identify potential thermal refuge areas.

  6. Identifying trout refuges in the Indian and Hudson Rivers in northern New York through airborne thermal infrared remote sensing

    USGS Publications Warehouse

    Ernst, Anne G.; Baldigo, Barry P.; Calef, Fred J.; Freehafer, Douglas A.; Kremens, Robert L.

    2015-01-01

    The locations and sizes of potential cold-water refuges for trout were examined in 2005 along a 27-kilometer segment of the Indian and Hudson Rivers in northern New York to evaluate the extent of refuges, the effects of routine flow releases from an impoundment, and how these refuges and releases might influence trout survival in reaches that otherwise would be thermally stressed. This river segment supports small populations of brook trout (Salvelinus fontinalis), brown trout (Salmo trutta), and rainbow trout (Oncorhynchus mykiss) and also receives regular releases of reservoir-surface waters to support rafting during the summer, when water temperatures in both the reservoir and the river frequently exceed thermal thresholds for trout survival. Airborne thermal infrared imaging was supplemented with continuous, in-stream temperature loggers to identify potential refuges that may be associated with tributary inflows or groundwater seeps and to define the extent to which the release flows decrease the size of existing refuges. In general, the release flows overwhelmed the refuge areas and greatly decreased the size and number of the areas. Mean water temperatures were unaffected by the releases, but small-scale heterogeneity was diminished. At a larger scale, water temperatures in the upper and lower segments of the reach were consistently warmer than in the middle segment, even during passage of release waters. The inability of remote thermal infrared images to consistently distinguish land from water (in shaded areas) and to detect groundwater seeps (away from the shallow edges of the stream) limited data analysis and the ability to identify potential thermal refuge areas.

  7. Selectable Hyperspectral Airborne Remote-sensing Kit (SHARK) on the Vision II turbine rotorcraft UAV over the Florida Keys

    NASA Astrophysics Data System (ADS)

    Holasek, R. E.; Nakanishi, K.; Swartz, B.; Zacaroli, R.; Hill, B.; Naungayan, J.; Herwitz, S.; Kavros, P.; English, D. C.

    2013-12-01

    As part of the NASA ROSES program, the NovaSol Selectable Hyperspectral Airborne Remote-sensing Kit (SHARK) was flown as the payload on the unmanned Vision II helicopter. The goal of the May 2013 data collection was to obtain high resolution visible and near-infrared (visNIR) hyperspectral data of seagrasses and coral reefs in the Florida Keys. The specifications of the SHARK hyperspectral system and the Vision II turbine rotorcraft will be described along with the process of integrating the payload to the vehicle platform. The minimal size, weight, and power (SWaP) specifications of the SHARK system is an ideal match to the Vision II helicopter and its flight parameters. One advantage of the helicopter over fixed wing platforms is its inherent ability to take off and land in a limited area and without a runway, enabling the UAV to be located in close proximity to the experiment areas and the science team. Decisions regarding integration times, waypoint selection, mission duration, and mission frequency are able to be based upon the local environmental conditions and can be modified just prior to take off. The operational procedures and coordination between the UAV pilot, payload operator, and scientist will be described. The SHARK system includes an inertial navigation system and digital elevation model (DEM) which allows image coordinates to be calculated onboard the aircraft in real-time. Examples of the geo-registered images from the data collection will be shown. SHARK mounted below VTUAV. SHARK deployed on VTUAV over water.

  8. Airborne Multi-wavelength High Spectral Resolution Lidar for Process Studies and Assessment of Future Satellite Remote Sensing Concepts

    NASA Astrophysics Data System (ADS)

    Hostetler, C. A.; Ferrare, R. A.; Hair, J. W.; Cook, A. L.; Harper, D. B.; Mack, T. L.; Hare, R. J.; Cleckner, C. S.; Rogers, R.; Mueller, D.; Chemyakin, E.; Burton, S. P.; Obland, M. D.; Scarino, A. J.; Cairns, B.; Russell, P. B.; Redemann, J.; Shinozuka, Y.; Schmid, B.; Berg, L. K.; Fast, J. D.; Flynn, C. J.

    2012-12-01

    NASA Langley recently developed the world's first airborne multi-wavelength high spectral resolution lidar (HSRL). This lidar employs the HSRL technique at 355 and 532 nm to make independent, unambiguous retrievals of aerosol extinction and backscatter. It also employs the standard backscatter technique at 1064 nm and is polarization-sensitive at all three wavelengths. This instrument, dubbed HSRL-2 (the second-generation HSRL developed by NASA Langley), is a prototype for the lidar on NASA's planned Aerosols-Clouds-Ecosystems (ACE) mission. HSRL-2 completed its first science mission in July 2012, the Two-Column Aerosol Project (TCAP) conducted by the Department of Energy (DOE) in Hyannis, MA. TCAP presents an excellent opportunity to assess some of the remote sensing concepts planned for ACE: HSRL-2 was deployed on the Langley King Air aircraft with another ACE-relevant instrument, the NASA GISS Research Scanning Polarimeter (RSP), and flights were closely coordinated with the DOE's Gulfstream-1 aircraft, which deployed a variety of in situ aerosol and trace gas instruments and the new Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR). The DOE also deployed their Atmospheric Radiation Measurement Mobile Facility and their Mobile Aerosol Observing System at a ground site located on the northeastern coast of Cape Cod for this mission. In this presentation we focus on the capabilities, data products, and applications of the new HSRL-2 instrument. Data products include aerosol extinction, backscatter, depolarization, and optical depth; aerosol type identification; mixed layer depth; and range-resolved aerosol microphysical parameters (e.g., effective radius, index of refraction, single scatter albedo, and concentration). Applications include radiative closure studies, studies of aerosol direct and indirect effects, investigations of aerosol-cloud interactions, assessment of chemical transport models, air quality studies, present (e.g., CALIPSO

  9. Snowpack Microstructure Characterization and Partial Coherent and Fully Coherent Forward Scattering Models in Microwave Remote Sensing

    NASA Astrophysics Data System (ADS)

    Tan, S.; Tsang, L.; Xu, X.; Ding, K. H.

    2015-12-01

    In this paper we describe partial coherent model and fully coherent snowpack scattering model based on numerical simulation of Maxwell's equation. In medium characterization, we derive the correlation functions from the pair distribution functions of sticky spheres and multiple-size spheres used in QCA. We show that both the Percus-Yevick pair functions and the bicontinuous model have tails in the correlation functions that are distinctly different from the traditional exponential correlation functions. The methodologies of using ground measurements of grain size distributions and correlation functions to obtain model parameters are addressed. The DMRT theory has been extended to model the backscattering enhancement. We developed the methodology of cyclical corrections beyond first order to all orders of multiple scattering. This enables the physical modeling of combined active and passive microwave remote sensing of snow over the same scene. The bicontinuous /DMRT is applied to compare with data acquired in the NoSREx campaign, and the model results are validated against coincidental active and passive measurements using the same set of physical parameters of snow in all frequency and polarization channels. The DMRT is a partially coherent approach that one accounts for the coherent wave interaction only within few wavelengths as represented by phase matrix. However, the phase information of field is lost in propagating the specific intensity via RT and this hinders the use of DMRT in coherent synthetic aperture radar (SAR) analysis, including InSAR, PolInSAR and Tomo-SAR. One can alternatively calculate the scattering matrix of the terrestrial snowpack above ground by solving the volume integral equations directly with half space Green's function. The scattering matrix of the snowpack is computed for each realization giving rise to the speckle statistics. The resulting bistatic scattering automatically includes the backscattering enhancement effects. Tomograms of

  10. Sensors and methods for weather-independent remote sensing with microwaves

    NASA Technical Reports Server (NTRS)

    Keydel, W.

    1981-01-01

    Sensors and methods of radar and microwave radiometry which operate in the millimeter wave range are discussed. The properties of electromagnetic waves are discussed as well as the resolution capacity and measurement accuracy of sensor systems.

  11. Remote sensing of snow properties by passive microwave radiometry: GSFC truck experiment

    NASA Technical Reports Server (NTRS)

    Chang, A. T. C.; Rango, A.; Shiue, J.

    1980-01-01

    Recent results indicate that microwave radiometry has the potential for inferring the snow depth and water equivalent information from snowpacks. In order to assess this potential for determining the water equivalent of a snowpack, it is necessary to understand the microwave emission and scattering behavior of the snow at various wavelengths under carefully controlled conditions. Truck-mounted microwave instrumentation was used to study the microwave characteristics of the snowpack in the Colorado Rocky Mountain region during the winters of 1977 to 78 and 7978 to 79. The spectral signatures of C, X, K sub u, and K sub a band radiometers with dual polarization were used, together with measurements of snowpack density, temperature an ram profiles, liquid water content, and rough characterization of the crystal sizes. These data compared favorably with calculated results based on recent microscopic scattering models.

  12. Microwave remote sensing of sea ice in the AIDJEX Main Experiment

    USGS Publications Warehouse

    Campbell, W.J.; Wayenberg, J.; Ramseyer, J.B.; Ramseier, R.O.; Vant, M.R.; Weaver, R.; Redmond, A.; Arsenaul, L.; Gloersen, P.; Zwally, H.J.; Wilheit, T.T.; Chang, T.C.; Hall, D.; Gray, L.; Meeks, D.C.; Bryan, M.L.; Barath, F.T.; Elachi, C.; Leberl, F.; Farr, Tom

    1978-01-01

    During the AIDJEX Main Experiment, April 1975 through May 1976, a comprehensive microwave sensing program was performed on the sea ice of the Beaufort Sea. Surface and aircraft measurements were obtained during all seasons using a wide variety of active and passive microwave sensors. The surface program obtained passive microwave measurements of various ice types using four antennas mounted on a tracked vehicle. In three test regions, each with an area of approximately 1.5 ?? 104 m2, detailed ice crystallographic, dielectric properties, and brightness temperatures of first-year, multiyear, and first-year/multiyear mixtures were measured. A NASA aircraft obtained passive microwave measurements of the entire area of the AIDJEX manned station array (triangle) during each of 18 flights. This verified the earlier reported ability to distinguish first-year and multiyear ice types and concentration and gave new information on ways to observe ice mixtures and thin ice types. The active microwave measurements from aircraft included those from an X- and L-band radar and from a scatterometer. The former is used to study a wide variety of ice features and to estimate deformations, while both are equally usable to observe ice types. With the present data, only the scatterometer can be used to distinguish positively multiyear from first-year and various types of thin ice. This is best done using coupled active and passive microwave sensing. ?? 1978 D. Reidel Publishing Company.

  13. Using airborne HIAPER Pole-to-Pole Observations (HIPPO) to evaluate model and remote sensing estimates of atmospheric carbon dioxide

    NASA Astrophysics Data System (ADS)

    Frankenberg, Christian; Kulawik, Susan S.; Wofsy, Steven C.; Chevallier, Frédéric; Daube, Bruce; Kort, Eric A.; O'Dell, Christopher; Olsen, Edward T.; Osterman, Gregory

    2016-06-01

    In recent years, space-borne observations of atmospheric carbon dioxide (CO2) have been increasingly used in global carbon-cycle studies. In order to obtain added value from space-borne measurements, they have to suffice stringent accuracy and precision requirements, with the latter being less crucial as it can be reduced by just enhanced sample size. Validation of CO2 column-averaged dry air mole fractions (XCO2) heavily relies on measurements of the Total Carbon Column Observing Network (TCCON). Owing to the sparseness of the network and the requirements imposed on space-based measurements, independent additional validation is highly valuable. Here, we use observations from the High-Performance Instrumented Airborne Platform for Environmental Research (HIAPER) Pole-to-Pole Observations (HIPPO) flights from 01/2009 through 09/2011 to validate CO2 measurements from satellites (Greenhouse Gases Observing Satellite - GOSAT, Thermal Emission Sounder - TES, Atmospheric Infrared Sounder - AIRS) and atmospheric inversion models (CarbonTracker CT2013B, Monitoring Atmospheric Composition and Climate (MACC) v13r1). We find that the atmospheric models capture the XCO2 variability observed in HIPPO flights very well, with correlation coefficients (r2) of 0.93 and 0.95 for CT2013B and MACC, respectively. Some larger discrepancies can be observed in profile comparisons at higher latitudes, in particular at 300 hPa during the peaks of either carbon uptake or release. These deviations can be up to 4 ppm and hint at misrepresentation of vertical transport. Comparisons with the GOSAT satellite are of comparable quality, with an r2 of 0.85, a mean bias μ of -0.06 ppm, and a standard deviation σ of 0.45 ppm. TES exhibits an r2 of 0.75, μ of 0.34 ppm, and σ of 1.13 ppm. For AIRS, we find an r2 of 0.37, μ of 1.11 ppm, and σ of 1.46 ppm, with latitude-dependent biases. For these comparisons at least 6, 20, and 50 atmospheric soundings have been averaged for GOSAT, TES, and AIRS

  14. Applications of remote sensing for water quality and biological measurements in coastal waters

    NASA Technical Reports Server (NTRS)

    Johnson, R. W.; Harriss, R. C.

    1979-01-01

    Potential applications of remote sensing technology to the study of coastal marine environments are reviewed, emphasizing water quality and biological measurements. Parameters measurable by airborne or spaceborne remote sensors include particulates, measured by visual or multispectral photography, chlorophyll a, measured by the Ocean Color Scanner or Coastal Zone Color Scanner, temperature distributions, by IR or microwave sensors, and salinity, by means of microwave radiometers. Research projects in which wide area synoptic or repetitive remote sensing can make a major contribution include the study of estuarine and continental shelf sediment transport dynamics, marine pollutant transport, marine phytoplankton dynamics and ocean fronts.

  15. High fidelity remote sensing of snow properties from MODIS and the Airborne Snow Observatory: Snowflakes to Terabytes

    NASA Astrophysics Data System (ADS)

    Painter, T.; Mattmann, C. A.; Brodzik, M.; Bryant, A. C.; Goodale, C. E.; Hart, A. F.; Ramirez, P.; Rittger, K. E.; Seidel, F. C.; Zimdars, P. A.

    2012-12-01

    The response of the cryosphere to climate forcings largely determines Earth's climate sensitivity. However, our understanding of the strength of the simulated snow albedo feedback varies by a factor of three in the GCMs used in the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, mainly caused by uncertainties in snow extent and the albedo of snow-covered areas from imprecise remote sensing retrievals. Additionally, the Western US and other regions of the globe depend predominantly on snowmelt for their water supply to agriculture, industry and cities, hydroelectric power, and recreation, against rising demand from increasing population. In the mountains of the Upper Colorado River Basin, dust radiative forcing in snow shortens snow cover duration by 3-7 weeks. Extended to the entire upper basin, the 5-fold increase in dust load since the late-1800s results in a 3-week earlier peak runoff and a 5% annual loss of total runoff. The remotely sensed dynamics of snow cover duration and melt however have not been factored into hydrological modeling, operational forecasting, and policymaking. To address these deficiencies in our understanding of snow properties, we have developed and validated a suite of MODIS snow products that provide accurate fractional snow covered area and radiative forcing of dust and carbonaceous aerosols in snow. The MODIS Snow Covered Area and Grain size (MODSCAG) and MODIS Dust Radiative Forcing in Snow (MODDRFS) algorithms, developed and transferred from imaging spectroscopy techniques, leverage the complete MODIS surface reflectance spectrum. The two most critical properties for understanding snowmelt runoff and timing are the spatial and temporal distributions of snow water equivalent (SWE) and snow albedo. We have created the Airborne Snow Observatory (ASO), an imaging spectrometer and scanning LiDAR system, to quantify SWE and snow albedo, generate unprecedented knowledge of snow properties, and provide complete

  16. Microwave backscatter and emission observed from Shuttle Imaging Radar B and an airborne 1.4 GHz radiometer

    NASA Technical Reports Server (NTRS)

    Wang, J. R.; Schiue, J. C.; Schmugge, T. J.; Engman, E. T.; Mo, T.; Lawrence, R. W.

    1985-01-01

    A soil moisture experiment conducted with the Shuttle Imaging Radar B (SIR-B) is reported. SIR-B operated at 1.28 GHz provided the active microwave measurements, while a 4-beam pushbroom 1.4 GHz radiometer gave the complementary passive microwave measurements. The aircraft measurements were made at an altitude of 330 m, resulting in a ground resolution cell of about 100 m diameter. SIR-B ground resolution from 225 km was about 35 m. More than 150 agricultural fields in the San Joaquin Valley of California were examined in the experiment. The effect of surface roughness height on radar backscatter and radiometric measurements was studied.

  17. Comparison of ClO measurements by airborne and spaceborne microwave radiometers in the Arctic winter stratosphere 1993

    SciTech Connect

    Crewell, S.; Fabian, R.; Kuenzi, K.

    1995-06-15

    In February 1993 measurements of chlorine monoxide ClO, one of the key substances in catalytic ozone destruction, were performed over Scandinavia by two microwave receivers, the Submillimeter Atmospheric Sounder (SUMAS) on board the German research aircraft FALCON and the Microwave Limb Sounder (MLS) on board the Upper Atmospheric Research Satellite (UARS). High ClO concentrations (>1 ppb) inside the polar vortex at approximately 20km altitude were detected by both experiments. A comparison shows good agreement of both sensors in the location of enhanced ClO. 11 refs., 5 figs.

  18. Recent Improvements in Retrieving Near-Surface Air Temperature and Humidity Using Microwave Remote Sensing

    NASA Technical Reports Server (NTRS)

    Roberts, J. Brent

    2010-01-01

    Detailed studies of the energy and water cycles require accurate estimation of the turbulent fluxes of moisture and heat across the atmosphere-ocean interface at regional to basin scale. Providing estimates of these latent and sensible heat fluxes over the global ocean necessitates the use of satellite or reanalysis-based estimates of near surface variables. Recent studies have shown that errors in the surface (10 meter)estimates of humidity and temperature are currently the largest sources of uncertainty in the production of turbulent fluxes from satellite observations. Therefore, emphasis has been placed on reducing the systematic errors in the retrieval of these parameters from microwave radiometers. This study discusses recent improvements in the retrieval of air temperature and humidity through improvements in the choice of algorithms (linear vs. nonlinear) and the choice of microwave sensors. Particular focus is placed on improvements using a neural network approach with a single sensor (Special Sensor Microwave/Imager) and the use of combined sensors from the NASA AQUA satellite platform. The latter algorithm utilizes the unique sampling available on AQUA from the Advanced Microwave Scanning Radiometer (AMSR-E) and the Advanced Microwave Sounding Unit (AMSU-A). Current estimates of uncertainty in the near-surface humidity and temperature from single and multi-sensor approaches are discussed and used to estimate errors in the turbulent fluxes.

  19. Extended ocular hazard distances associated with intrabeam aided viewing of the Sandia remote sensing system, airborne aura laser (Big Sky Variant).

    SciTech Connect

    Augustoni, Arnold L.

    2004-08-01

    A laser hazard analysis to determine the Extended Ocular Hazard Distances associated with a possible intrabeam aided viewing of the Sandia Remote Sensing System (SRSS) airborne AURA laser (Big Sky Laser Technology) was performed based on the 2000 version of the American National Standard Institute's (ANSI) Standard Z136.1, for the Safe Use of Lasers and the 2000 version of the ANSI Standard Z136.6, for the Safe Use of Lasers Outdoors. The AURA lidar system is installed in the instrument pod of a Proteus airframe and is used to perform laser interaction experiments and tests at various national test sites. The targets are located at various distances (ranges) from the airborne platform. Nominal Ocular Hazard Distance (NOHD) and maximum ''eye-safe'' dwell times for various operational altitudes associated with unaided intrabeam exposure of ground personnel were determined and presented in a previous SAND report. Although the target areas are controlled and the use of viewing aids are prohibited there is the possibility of the unauthorized use of viewing aids such as binoculars. This aided viewing hazard analysis is supplemental to the previous SAND report for the laser hazard analysis of the airborne AURA.

  20. Basic properties of developed wind waves and their influence on microwave remote sensing signatures

    NASA Technical Reports Server (NTRS)

    Glazman, Roman E.; Pilorz, Stuart H.

    1989-01-01

    Error trends in wind speed measurements by satellite scatterometer altimeter and microwave radiometer are shown to be correlated with the degree of wave development. These errors are analyzed theoretically by studying the rms wave slope which, directly or indirectly, affects all microwave signatures. For equilibrium sea state, the influence of spectrum parameters on the wave slope is reviewed. In well-developed seas, the dominant wavelength is shown to have no effect on the slope. Temporal-spatial rates of steep and breaking waves are derived and compared with field observations. The inner scale that determines a rapid falloff of spectral density function at high frequencies is estimated. The dependence of the spectral parameters on wind speed and sea maturity is studied using NOAA buoy observations. It is concluded that the removal of environmental error trends from satellite measurements can be best accomplished by a joint processing of microwave returns from several independent instruments.

  1. Airborne remote sensing in precision viticolture: assessment of quality and quantity vineyard production using multispectral imagery: a case study in Velletri, Rome surroundings (central Italy)

    NASA Astrophysics Data System (ADS)

    Tramontana, Gianluca; Papale, Dario; Girard, Filippo; Belli, Claudio; Pietromarchi, Paolo; Tiberi, Domenico; Comandini, Maria C.

    2009-09-01

    During 2008 an experimental study aimed to investigate the capabilities of a new Airborne Remote sensing platform as an aid in precision viticulture was conducted. The study was carried out on 2 areas located in the town of Velletri, near Rome; the acquisitions were conducted on 07-08-2008 and on 09-09-2008, using ASPIS (Advanced Spectroscopic Imager System) the new airborne multispectral sensor, capable to acquire 12 narrow spectral bands (10 nm) located in the visible and near-infrared region. Several vegetation indices, for a total of 22 independent variables, were tested for the estimation of different oenological parameters. Anova test showed that several oenochemical parameters, such as sugars and acidity, differ according to the variety taken into consideration. The remotely sensed data were significantly correlated with the following oenochemical parameters: Leaf Surface Exposed (SFE) (correlation coefficient R2 ~ 0.8), wood pruning (R2 ~ 0.8), reducing sugars (R2 ~ 0.6 and Root Mean Square Error ~ 5g/l), total acidity (R2 ~ 0.6 and RMSE ~ 0.5 g/l), polyphenols (R2~ 0.9) and anthocyanins content (R2 ~ 0.89) in order to provide "prescriptives" thematic maps related to the oenological variables of interest, the relationships previously carried out have been applied to the vegetation indices.

  2. Passive microwave remote sensing of soil moisture: Results from HAPEX, FIFE, and MONSOON 90

    NASA Technical Reports Server (NTRS)

    Schmugge, Thomas; Jackson, T. J.; Wang, J. R.

    1991-01-01

    HAPEX (Hydrologic Atmospheric Pilot Experiment), FIFE (First ISLSCP Field Experiment) and MONSOON 90 which used an imaging microwave radiometer operating at a frequency of 1.42 GHz are reported. For FIFE and MONSOON 90, a wide range of moisture conditions were present and it was possible to observe the drydown of the soil following heavy rain and to map its spatial variation. The quantitive agreement of microwave observations and ground measurements was very good. In HAPEX there were no significant rains and conditions were generally rather dry, however, moisture variations due to irrigation were observed.

  3. Passive microwave remote sensing of soil moisture - Results from HAPEX, FIFE and MONSOON 90

    NASA Technical Reports Server (NTRS)

    Schmugge, T.; Jackson, T. J.; Kustas, W. P.; Wang, J. R.

    1992-01-01

    HAPEX (Hydrologic Atmospheric Pilot Experiment), FIFE (First ISLSCP Field Experiment) and MONSOON 90 which used an imaging microwave radiometer operating at a frequency of 1.42 GHz are reported. For FIFE and MONSOON 90, a wide range of moisture conditions were present and it was possible to observe the drydown of the soil following heavy rain and to map its spatial variation. The quantitative agreement of microwave observations and ground measurements was very good. In HAPEX there were no significant rains and conditions were generally rather dry, however, moisture variations due to irrigation were observed.

  4. Synergy of spaceborne remote sensing and airborne in situ observations for the study of Arctic mixed phase clouds at regional and small scales

    NASA Astrophysics Data System (ADS)

    Mioche, G.; Jourdan, O.; Delanoë, J.; Gourbeyre, C.; Dupuy, R.; Guyot, G.; Szczap, F.; Schwarzenboeck, A.

    2015-12-01

    Clouds radiation feedback processes in the Arctic have been identified as one of the greatest sources of uncertainties in the prediction of global climate in GCMs. In particular, mixed phase clouds (MPC) occur very frequently at low-level altitudes in the Arctic, representing between 30% and 50% of the clouds all along the year. However, the characterization of MPC on the whole Arctic region is not yet accurate enough to better understand cloud-radiation interactions. Thus, the knowledge of arctic MPC properties has to be improved. The aim of this study is to characterize MPC properties from regional scale to small scale. This work is based on the synergy of spaceborne active remote sensing (CALIPSO/CloudSat) and airborne in situ observations. We will present results about the time and space variability and vertical distribution of MPC over the entire Arctic region, with a focus on the Svalbard region. The influence of the seasonal cycle as well as surface type (open sea, sea ice, land) on the MPC occurrences will also be investigated. Then, this study will focus on a statistical analysis of MPC clouds properties based on in situ measurements carried out during several airborne campaigns in Svalbard region (14 flights corresponding to 54 vertical profiles). This will provide a detailed characterization of microphysical and optical properties of MPC, discriminating liquid and ice phases. Small scale processes occurring in arctic clouds will be also studied. Finally, accurate profiles of relevant clouds parameters (optical depth, liquid/water fraction, ice crystals morphology, ice and liquid water contents…) will be assessed to contribute to the improvement of clouds representation in global and mesoscale models and to improve airborne and spatial remote sensing retrievals algorithms.

  5. Synergy of spaceborne remote sensing and airborne in situ observations for the study of Arctic mixed phase clouds at regional and small scales

    NASA Astrophysics Data System (ADS)

    Mioche, G.; Jourdan, O.; Delanoë, J.; Gourbeyre, C.; Dupuy, R.; Guyot, G.; Szczap, F.; Schwarzenboeck, A.

    2014-12-01

    Clouds radiation feedback processes in the Arctic have been identified as one of the greatest sources of uncertainties in the prediction of global climate in GCMs. In particular, mixed phase clouds (MPC) occur very frequently at low-level altitudes in the Arctic, representing between 30% and 50% of the clouds all along the year. However, the characterization of MPC on the whole Arctic region is not yet accurate enough to better understand cloud-radiation interactions. Thus, the knowledge of arctic MPC properties has to be improved. The aim of this study is to characterize MPC properties from regional scale to small scale. This work is based on the synergy of spaceborne active remote sensing (CALIPSO/CloudSat) and airborne in situ observations. We will present results about the time and space variability and vertical distribution of MPC over the entire Arctic region, with a focus on the Svalbard region. The influence of the seasonal cycle as well as surface type (open sea, sea ice, land) on the MPC occurrences will also be investigated. Then, this study will focus on a statistical analysis of MPC clouds properties based on in situ measurements carried out during several airborne campaigns in Svalbard region (14 flights corresponding to 54 vertical profiles). This will provide a detailed characterization of microphysical and optical properties of MPC, discriminating liquid and ice phases. Small scale processes occurring in arctic clouds will be also studied. Finally, accurate profiles of relevant clouds parameters (optical depth, liquid/water fraction, ice crystals morphology, ice and liquid water contents…) will be assessed to contribute to the improvement of clouds representation in global and mesoscale models and to improve airborne and spatial remote sensing retrievals algorithms.

  6. The information of oil and gas micro-seepage in Dongsheng region of inner Mongolia based on the airborne hyperspectral remote sensing image

    NASA Astrophysics Data System (ADS)

    Tian, Shu-Fang; Chen, Jian-Ping; Zhou, Mi

    2008-11-01

    The technology of hyper-spectral remote sensing which has higher spatial resolution characteristic, and optimizes the qualification of identifying and extracting salt mines, not only enhances the capacity of natural scenes detection and recognition, but also advances the level of quantitative remote sensing. It has important meaning for using the technology of hyper-spectral remote sensing to quantitative extraction. The paper investigate gas micro-seepage based on the Airborne Hyper-spectral Remote Sensing in Dongsheng of Inner Mongolia on the basis of gas micro-seepage theory using EO-1 Hyperion data collected by Satellite-Borne Sensor which has highest spatial resolution presently in the world. On the basis of data pretreated this paper adopts band math extracted the distribution of oil and gas micro-seepage using diagnostic assimilating spectrum of alteration minerals by the numbers. With eigenvector length model evaluates the research area comprehensive index, oil and gas micro-seepage information model of the research area is established and key regions of oil and gas micro-seepage are confirmed, which offers academic gist for oil and gas resource exploitation of Dongsheng.

  7. Orbiting multi-beam microwave radiometer for soil moisture remote sensing

    NASA Technical Reports Server (NTRS)

    Shiue, J. C.; Lawrence, R. W.

    1985-01-01

    The effects of soil moisture and other factors on soil surface emissivity are reviewed and design concepts for a multibeam microwave radiometer with a 15 m antenna are described. Characteristic antenna gain and radiation patterns are shown and losses due to reflector roughness are estimated.

  8. Microwave Remote Sensing of Ocean Surface Wind Speed and Rain Rates over Tropical Storms

    NASA Technical Reports Server (NTRS)

    Swift, C. T.; Dehority, D. C.; Black, P. G.; Chien, J. Z.

    1984-01-01

    The value of using narrowly spaced frequencies within a microwave band to measure wind speeds and rain rates over tropical storms with radiometers is reviewed. The technique focuses on results obtained in the overflights of Hurricane Allen during 5 and 8 of August, 1980.

  9. The advanced microwave precipitation radiometer: A new aircraft radiometer for passive precipitation remote sensing

    NASA Technical Reports Server (NTRS)

    Hood, Robbie E.; Spencer, Roy W.; James, Mark W.

    1991-01-01

    Past studies of passive microwave measurements of precipitating systems have yielded broad empirical relationships between hydrometeors and microwave transmission. In general, these relationships fall into two categories of passive microwave precipitation retrievals rely upon the observed effect of liquid precipitation to increase the brightness temperature of a radiometrically cold background such as an ocean surface. A scattering-based method is based upon the effect that frozen hydrometeors tend to decrease the brightness temperature of a radiometrically warm background such as land. One step toward developing quantitative brightness temperature-rain rate relationships is the recent construction of a new aircraft instrument sponsored by National Aeronautics and Space Administration/Marshall Space Flight Center (NASA/MSFC). This instrument is the Advanced Microwave Precipitation Radiometer (AMPR) designed and built by Georgia Tech Research Institute to fly aboard high altitude research aircraft such as the NASA ER-2. The AMPR and its accompanying data acquisition system are mounted in the Q-bay compartment of the NASA ER-2.

  10. Wave theory for microwave remote sensing of a half-space random medium with three-dimensional variations

    NASA Technical Reports Server (NTRS)

    Tsang, L.; Kong, J. A.

    1979-01-01

    The two-variable expansion technique is used to solve for the mean Green's functions from the Dyson equation under the nonlinear approximation for a half-space random medium with three-dimensional correlation functions. The Bethe-Salpeter equations are then solved under the ladder approximation. The radiative transfer equations, which have been applied extensively in the study of microwave remote sensing problems, are derived under these approximations. The limiting cases of large and small horizontal correlation lengths are discussed. It is found that there is only one propagation constant except for the case of large horizontal correlation lengths, in which there are two propagation constants. It is shown that boundary layer appears in first-order solutions and does not appear in zeroth-order solutions.

  11. Remote identification of potential polar bear maternal denning habitat in northern Alaska using airborne LiDAR

    NASA Astrophysics Data System (ADS)

    Jones, B. M.; Durner, G. M.; Stoker, J.; Shideler, R.; Perham, C.; Liston, G. E.

    2013-12-01

    Polar bear (Ursus maritimus) populations throughout the Arctic are being threatened by reductions in critical sea ice habitat. Throughout much of their range, polar bears give birth to their young in winter dens that are excavated in snowdrifts. New-born cubs, which are unable to survive exposure to Arctic winter weather, require 2-3 months of the relatively warm, stable, and undisturbed environment of the den for their growth. In the southern Beaufort Sea (BS), polar bears may den on the Alaskan Arctic Coastal Plain (ACP).The proportion of dens occurring on land has increased because of reductions in stable multi-year ice, increases in unconsolidated ice, and lengthening of the fall open-water period. Large portions of the ACP are currently being used for oil and gas activities and proposed projects will likely expand this footprint in the near future. Since petroleum exploration and development activities increase during winter there is the potential for human activities to disturb polar bears in maternal dens. Thus, maps showing the potential distribution of terrestrial denning habitat can help to mitigate negative interactions. Prior remote sensing efforts have consisted of manual interpretation of vertical aerial photography and automated classification of Interferometric Synthetic Aperture (IfSAR) derived digital terrain models (DTM) (5-m spatial resolution) focused on the identification of snowdrift forming landscape features. In this study, we assess the feasibility of airborne Light Detection and Ranging (LiDAR) data (2-m spatial resolution) for the automated classification of potential polar bear maternal denning habitat in a 1,400 km2 area on the central portion of the ACP. The study region spans the BS coast from the Prudhoe Bay oilfield in the west to near Point Thompson in the east and extends inland from 10 to 30 km. Approximately 800 km2 of the study area contains 19 known den locations, 51 field survey sites with information on bank height and

  12. The development of a stepped frequency microwave radiometer and its application to remote sensing of the Earth

    NASA Technical Reports Server (NTRS)

    Harrington, R. F.

    1980-01-01

    The design, development, application, and capabilities of a variable frequency microwave radiometer are described. This radiometer demonstrated the versatility, accuracy, and stability required to provide contributions to the geophysical understanding of ocean and ice processes. A closed-loop feedback method was used, whereby noise pulses were added to the received electromagnetic radiation to achieve a null balance in a Dicke switched radiometer. Stability was achieved through the use of a constant temperature enclosure around the low loss microwave front end. The Dicke reference temperature was maintained to an absolute accuracy of 0.1 K using a closed-loop proportional temperature controller. A microprocessor based digital controller operates the radiometer and records the data on computer compatible tapes. This radiometer exhibits an absolute accuracy of better than 0.5 K when the sensitivity is 0.1 K. The sensitivity varies between 0.0125 K and 1.25 K depending upon the bandwidth and integration time selected by the digital controller. Remote sensing experiments were conducted from an aircraft platform and the first radiometeric mapping of an ocean polar front; exploratory experiments to measure the thickness of lake ice; first discrimination between first year and multiyear ice below 10 GHz; and the first known measurements of frequency sensitive characteristics of sea ice.

  13. Joint Variability of Airborne Passive Microwave and Ground-based Radar Observations Obtained in the TRMM Kwajalein Experiment

    NASA Astrophysics Data System (ADS)

    Yuter, S. E.; Kingsmill, D. E.

    2007-12-01

    The Tropical Rainfall Measuring Mission (TRMM) Kwajalein Experiment (KWAJEX) held July-September 1999 in the west Pacific was designed to obtain an empirical physical characterization of precipitating convective clouds over the tropical ocean. The majority of the precipitation was from mixed-phase clouds. Coordinated data sets were obtained from aircraft and ground-based sensors including passive microwave measurements by the Advanced Microwave Precipitation Radiometer (AMPR) instrument on the NASA DC-8 aircraft and S-band volumetric radar data by the KPOL radar. The AMPR and KPOL data sets were processed to yield a set of 25,049 matching observations at ~ 2 km x 2 km horizontal spatial resolution and within 6 min. The TRMM satellite Microwave Imager (TMI) has a similar set of channels to AMPR but coarser spatial resolution (19 GHz: 35 km, 85 GHz: 7.7 km). During KWAJEX, the 0 deg C level height was nearly constant at ~ 4800 m. Hence, two potential sources of uncertainty in relating passive microwave brightness temperatures (Tbs) to surface precipitation, inhomogeneous beam filling and variations in depth of the rain layer are much smaller sources of error in the KWAJEX data set than for TMI. TRMM was originally designed to yield monthly rainfall estimates over 5 deg x 5 deg grid boxes. The use of these data to yield instantaneous rainrate products at smaller spatial scales is more sensitive to the detailed characteristics of the joint distributions of passive microwave Tbs versus rain rate. KWAJEX data sets reveal poor correlations, very wide scatter, and weak modes in these distributions. The spread of emission Tb values for a given rain-layer reflectivity (e.g., 75 K at 30 dBZ for 19 GHz) is similar or larger within convective compared to stratiform precipitation regions. This result implies that the enhancement in emission Tbs associated with partially melted ice particles can occur whether the particles are concentrated within a thin layer in stratiform

  14. Making Carbon Emissions Remotely Sensible: Flux Observations of Carbon from an Airborne Laboratory (FOCAL), its Near-Surface Survey of Carbon Gases and Isotopologues on Alaska's North Slope

    NASA Astrophysics Data System (ADS)

    Dobosy, R.; Dumas, E. J.; Sayres, D. S.; Healy, C. E.; Munster, J. B.; Baker, B.; Anderson, J. G.

    2014-12-01

    Detailed process-oriented study of the mechanisms of conversion in the Arctic of fossil carbon to atmospheric gas is progressing, but necessarily limited to a few point locations and requiring detailed subsurface measurements inaccessible to remote sensing. Airborne measurements of concentration, transport and flux of these carbon gases at sufficiently low altitude to reflect surface variations can tie such local measurements to remotely observable features of the landscape. Carbon dioxide and water vapor have been observable for over 20 years from low-altitude small aircraft in the Arctic and elsewhere. Methane has been more difficult, requiring large powerful aircraft or limited flask samples. Recent developments in spectroscopy, however, have reduced the power and weight required to measure methane at rates suitable for eddy-covariance flux estimates. The Flux Observations of Carbon from an Airborne Laboratory (FOCAL) takes advantage of Integrated Cavity-Output Spectroscopy (ICOS) to measure CH4, CO2, and water vapor in a new airborne system. The system, moreover, measures these gases' stable isotopologues every two seconds or faster helping to separate thermogenic from biogenic emissions. Paired with the Best Airborne Turbulence (BAT) probe developed for small aircraft by NOAA's Air Resources Laboratory and a light twin-engine aircraft adapted by Aurora Flight Sciences Inc., the FOCAL measures at 6 m spacing, covering 100 km in less than 30 minutes. It flies between 10 m and 50 m above ground interspersed with profiles to the top of the boundary layer and beyond. This presentation gives an overview of the magnitude and variation in fluxes and concentrations of CH4, CO2, and H2O with space, time, and time of day in a spatially extensive survey, more than 7500 km total in 15 flights over roughly a 100 km square during the month of August 2013. An extensive data set such as this at low altitude with high-rate sampling addresses features that repeat on 1 km scale

  15. Comparison of remote measurements of infrared surface temperatures and microwave soil moisture

    NASA Technical Reports Server (NTRS)

    Perry, Eileen M.; Carlson, Toby N.

    1987-01-01

    Scatterometric measurements of active microwave soil water content and radiometric measurements of thermal IR surface temperatures were made simultaneously fron an aircraft flying 400 m over an agricultural region of France after harvesting. The surface temperatures were used to deterine soil moisture availability estimates according to the Carlson (1986) model. Surface temperature or soil moisture availability and microwave soil moisture were correlated. The standard error in the IR temperature and soil moisture availability due to influences other than soil moisture is found to be + or - 2 C. The standard deviation of the temperature/moisture availability is greater than this standard error. It is shown that correlations between soil water content and moisture availability improve with increasing spatial or temporal variance in the measure surface temperatures.

  16. Microwave remote sensing of soil moisture, volume 1. [Guymon, Oklahoma and Dalhart, Texas

    NASA Technical Reports Server (NTRS)

    Mcfarland, M. J. (Principal Investigator); Theis, S. W.; Rosenthal, W. D.; Jones, C. L.

    1982-01-01

    Multifrequency sensor data from NASA's C-130 aircraft were used to determine which of the all weather microwave sensors demonstrated the highest correlation to surface soil moisture over optimal bare soil conditions, and to develop and test techniques which use visible/infrared sensors to compensate for the vegetation effect in this sensor's response to soil moisture. The L-band passive microwave radiometer was found to be the most suitable single sensor system to estimate soil moisture over bare fields. The perpendicular vegetation index (PVI) as determined from the visible/infrared sensors was useful as a measure of the vegetation effect on the L-band radiometer response to soil moisture. A linear equation was developed to estimate percent field capacity as a function of L-band emissivity and the vegetation index. The prediction algorithm improves the estimation of moisture significantly over predictions from L-band emissivity alone.

  17. Dielectric properties in microwave remote plasma sustained in argon: Expanding plasma conditions

    SciTech Connect

    Jauberteau, J. L.; Jauberteau, I.

    2012-11-15

    This work is devoted to the study of the relative permittivity in argon expanding plasma produced below a microwave discharge sustained in a quartz tube and working at 2.45 GHz. We discuss results and explain the microwave propagation within the reactor, outside the quartz tube. It is shown that at low pressures (133 Pa) and at powers ranging from 100 W to 400 W, the wave frequency remains lower than the plasma frequency anywhere in the expanding plasma. Under these conditions, the real part of the relative permittivity is negative and the wave is reflected. Surprisingly, in these conditions, the plasma is produced inside and outside the quartz tube, below the wave launcher. This effect can be explained considering a surface wave propagating at the surface of the quartz tube then into the reactor, on the external surface of the expanding plasma below the quartz tube.

  18. Airborne Passive Remote Sensing of the Troposphere in Nashville/Middle Tennessee Area During the 1995 Southern Oxidants Study

    NASA Technical Reports Server (NTRS)

    Rider, D. M.; Worden, H. M.; Beer, R.; Nandi, S.; Sparks, L. C.

    1998-01-01

    In July of 1995 the Airborne Emission Spectrometer was deployed to Nashville, Tennessee to participate in the 1995 Ozone Study Intensive Campaign of the Southern Oxidants Study. AES is a high resolution mid-infrared interferometer that measures the spectrum of upwelling radiation in the 650-4250 cm-1 range.

  19. Galactic Noise and Passive Microwave Remote Sensing from Space at L-Band

    NASA Technical Reports Server (NTRS)

    LeVine, D. M.; Abraham, S.; Zukor, Dorothy J. (Technical Monitor)

    2000-01-01

    The spectral window at L-band (1.4 GHz) is important for passive remote sensing of parameters such as soil moisture and ocean salinity best measured at long wavelengths. At L-band, radiation from extraterrestrial (galactic) sources is strong enough to warrant inclusion in calibration and retrieval algorithms and unlike the constant cosmic background is spatially variable. Previous estimates of the magnitude and distribution of this background radiation have been rather coarse, However, recent surveys of the radio sky at 1.4 GHz have made it possible to produce maps with sufficient spatial and radiometric accuracy to be relevant to remote sensing applications. This is of particular concern for remote sensing of sea surface salinity because the surface (water) is a good reflector and the salinity signal is relatively small. This paper presents a modem map of the radiometric sky at L-band and a solution to the problem of determining the portion of the sky seen by a radiometer in orbit. The data is derived from recent radio astronomy surveys and is presented as equivalent brightness temperature suitable for remote sensing applications. Examples using orbits and antennas representative of those contemplated for remote sensing of soil moisture and sea surface salinity from space are presented to illustrate the signal levels to be expected. Radiation near the galactic plane can exceed several kelvin.

  20. Galactic Noise and Passive Microwave Remote Sensing from Space At L-Band

    NASA Technical Reports Server (NTRS)

    LeVine, David M.; Abraham, Saji; Hildebrand Peter H. (Technical Monitor)

    2002-01-01

    The spectral window at L-band (1.4 GHz) is important for passive remote sensing of soil moisture and ocean salinity from space, parameters that are needed to understand the hydrologic cycle and ocean circulation. At this frequency, radiation from extraterrestrial (mostly galactic) sources is strong and, unlike the constant cosmic background, this radiation is spatially variable. This paper presents a modern radiometric map of the celestial sky at L-band and a solution for the problem of determining what portion of the sky is seen by a radiometer in orbit. The data for the radiometric map is derived from recent radio astronomy surveys and is presented as equivalent brightness temperature suitable for remote sensing applications. Examples using orbits and antennas representative of those contemplated for remote sensing of soil moisture and sea surface salinity from space are presented to illustrate the signal levels to be expected. Near the galactic plane, the contribution can exceed several Kelvin.

  1. Mapping surface energy flux partitioning at large scales with optical and microwave remote sensing data from Washita '92

    NASA Astrophysics Data System (ADS)

    Kustas, William P.; Zhan, Xiwu; Jackson, Thomas J.

    1999-01-01

    A model evaluating the energy balance of the soil/substrate and vegetation (i.e., two-source) was applied to remotely sensed near-surface soil moisture maps generated from passive microwave data collected during the Washita '92 experiment. Model parameters were derived from a soil texture and a land-use/land cover database along with a normalized difference vegetation index map created from a SPOT satellite image. The Bowen ratio (BO, ratio of sensible to latent heat flux) was used for investigating the temporal and spatial variability in model output. Comparisons between predicted and observed heat fluxes were made with values summed over the daytime period. Daily maps of midday BO indicated areas with low vegetation cover or bare soil and senescent vegetation were drying out significantly (i.e., dramatic increases in BO), while other areas with higher vegetation cover showed smaller increases in BO in response to a drying soil surface. This result agrees with the profile soil moisture and surface flux observations indicating adequate moisture was available to the vegetation for meeting atmospheric demand. The predicted daytime fluxes agreed to within 1 mm of the observations with ≈25% difference between modeled and observed daytime evapotranspiration. Differences between modeled and measured surface temperatures averaged ≈2 K. The discrepancies between model output and observations are similar to the uncertainty in these measurements, indicating that the model provided reliable daytime energy flux maps for the Washita '92 study area using remotely sensed near-surface soil moisture.

  2. Detection of Severe Rain on Snow events using passive microwave remote sensing

    NASA Astrophysics Data System (ADS)

    Grenfell, T. C.; Putkonen, J.

    2007-12-01

    Severe wintertime rain-on-snow (ROS) events create a strong ice layer or layers in the snow on arctic tundra that act as a barrier to ungulate grazing. These events are linked with large-scale ungulate herd declines via starvation and reduced calf production rate when the animals are unable to penetrate through the resulting ice layer. ROS events also produce considerable perturbation in the mean wintertime soil temperature beneath the snow pack. ROS is a sporadic but well-known and significant phenomenon that is currently very poorly documented. Characterization of the distribution and occurrence of severe rain-on-snow events is based only on anecdotal evidence, indirect observations of carcasses found adjacent to iced snow packs, and irregular detection by a sparse observational weather network. We have analyzed in detail a particular well-identified ROS event that took place on Banks Island in early October 2003 that resulted in the death of 20,000 musk oxen. We make use of multifrequency passive microwave imagery from the special sensing microwave imager satellite sensor suite (SSM/I) in conjunction with a strong-fluctuation-theory (SFT) emissivity model. We show that a combination of time series analysis and cluster analysis based on microwave spectral gradients and polarization ratios provides a means to detect the stages of the ROS event resulting from the modification of the vertical structure of the snow pack, specifically wetting the snow, the accumulation of liquid water at the base of the snow during the rain event, and the subsequent modification of the snowpack after refreezing. SFT model analysis provides quantitative confirmation of our interpretation of the evolution of the microwave properties of the snowpack as a result of the ROS event. In particular, in addition to the grain coarsening due to destructive metamorphism, we detect the presence of the internal water and ice layers, directly identifying the physical properties producing the

  3. Evaluation of an airborne remote sensing platform consisting of two consumer-grade cameras for crop identification

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Remote sensing systems based on consumer-grade cameras have been increasingly used in scientific research and remote sensing applications because of their low cost and ease of use. However, the performance of consumer-grade cameras for practical applications have not been well documented in related ...

  4. Remote distinction of a noxious weed (musk thistle: Carduus nutans) using airborne hyperspectral imagery and the support vector machine classifier

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Remote detection of invasive plant species using geospatial imagery may significantly improve monitoring, planning, and management practices by eliminating shortfalls such as observer bias and accessibility involved in ground-based surveys. The use of remote sensing for accurate mapping invasion ex...

  5. Use of land surface remotely sensed satellite and airborne data for environmental exposure assessment in cancer research

    PubMed Central

    MAXWELL, SUSAN K.; MELIKER, JAYMIE R.; GOOVAERTS, PIERRE

    2015-01-01

    In recent years, geographic information systems (GIS) have increasingly been used for reconstructing individual-level exposures to environmental contaminants in epidemiological research. Remotely sensed data can be useful in creating space-time models of environmental measures. The primary advantage of using remotely sensed data is that it allows for study at the local scale (e.g., residential level) without requiring expensive, time-consuming monitoring campaigns. The purpose of our study was to identify how land surface remotely sensed data are currently being used to study the relationship between cancer and environmental contaminants, focusing primarily on agricultural chemical exposure assessment applications. We present the results of a comprehensive literature review of epidemiological research where remotely sensed imagery or land cover maps derived from remotely sensed imagery were applied. We also discuss the strengths and limitations of the most commonly used imagery data (aerial photographs and Landsat satellite imagery) and land cover maps. PMID:19240763

  6. Use of land surface remotely sensed satellite and airborne data for environmental exposure assessment in cancer research

    USGS Publications Warehouse

    Maxwell, S.K.; Meliker, J.R.; Goovaerts, P.

    2010-01-01

    In recent years, geographic information systems (GIS) have increasingly been used for reconstructing individual-level exposures to environmental contaminants in epidemiological research. Remotely sensed data can be useful in creating space-time models of environmental measures. The primary advantage of using remotely sensed data is that it allows for study at the local scale (e.g., residential level) without requiring expensive, time-consuming monitoring campaigns. The purpose of our study was to identify how land surface remotely sensed data are currently being used to study the relationship between cancer and environmental contaminants, focusing primarily on agricultural chemical exposure assessment applications. We present the results of a comprehensive literature review of epidemiological research where remotely sensed imagery or land cover maps derived from remotely sensed imagery were applied. We also discuss the strengths and limitations of the most commonly used imagery data (aerial photographs and Landsat satellite imagery) and land cover maps. ?? 2010 Nature Publishing Group All rights reserved.

  7. Noise considerations for remote detection of life signs with microwave Doppler radar.

    PubMed

    Nguyen, Dung; Yamada, Shuhei; Park, Byung-Kwon; Lubecke, Victor; Boric-Lubecke, Olga; Host-Madsen, Anders

    2007-01-01

    This paper describes and quantifies three main sources of baseband noise affecting physiological signals in a direct conversion microwave Doppler radar for life signs detection. They are thermal noise, residual phase noise, and Flicker noise. In order to increase the SNR of physiological signals at baseband, the noise floor, in which the Flicker noise is the most dominant factor, needs to be minimized. This paper shows that with the consideration of the noise factor in our Doppler radar, Flicker noise canceling techniques may drastically reduce the power requirement for heart rate signal detection by as much as a factor of 100.

  8. Snow water equivalent determination by microwave radiometry

    NASA Technical Reports Server (NTRS)

    Chang, A. T. C.; Foster, J. L.; Hall, D. K.; Rango, A.; Hartline, B. K.

    1981-01-01

    One of the most important parameters for accurate snowmelt runoff prediction is snow water equivalent (SWE) which is contentionally monitored using observations made at widely scattered points in or around specific watersheds. Remote sensors which provide data with better spatial and temporal coverage can be used to improve the SWE estimates. Microwave radiation, which can penetrate through a snowpack, may be used to infer the SWE. Calculations made from a microscopic scattering model were used to simulate the effect of varying SWE on the microwave brightness temperature. Data obtained from truck mounted, airborne and spaceborne systems from various test sites were studied. The simulated SWE compares favorable with the measured SWE. In addition, whether the underlying soil is frozen or thawed can be discriminated successfully on the basis of the polarization of the microwave radiation.

  9. Characterizing Status of Selected Ecosystems Using Optical and Microwave Remote Sensing Data

    NASA Astrophysics Data System (ADS)

    Dabrowska-Zielinska, Katarzyna; Budzynska, Maria; Kowalik, Wanda; Malek, Iwona; Turlej, Konrad

    2010-12-01

    Wetlands areas are one of the most sensitive ecosystem. This study was conducted in the Biebrza Valley, a NATURA 2000 and Ramsar Convention test site situated in Northeast Poland. The paper presents monitoring and mapping of various soil-vegetation variables using optical and microwave satellite data. Satellite data applied for the study included: ENVISAT ASAR and MERIS, ALOS.PALSAR, NOAA.AVHRR. Optical images were used for classification of wetlands communities and calculation of vegetation indices. The method of estimating Latent Heat Flux (LE) from NOAA.AVHRR and meteorological data and calculation of soil moisture index as ratio of Sensible Heat Flux (H) to LE were also applied. Parallel to satellite observations the soil-vegetation variables were measured at the test site. Data from optical and microwave satellite images and soil-vegetation ground truth measurements were analysed to develop methods for the Leaf Area Index (LAI) and soil moisture estimates over wetlands. The presented results allow monitoring and mapping soil-vegetation parameters of wetlands and its changes over the time. The methodology developed is suitable for applications to the system of monitoring wetlands in Europe. The studied areas can be recognized as a reference for other wetlands. The examined ecosystem is of great importance in nature conservation and water storage capability in Europe. The Project was carried out in the framework of the national grant N N526 0217 33. The satellite images have been obtained for ESA projects AO ID 122 and AOALO.3742.

  10. Remote sensing of precipitable water over the oceans from Nimbus-7 microwave measurements

    NASA Technical Reports Server (NTRS)

    Prabhakara, C.; Change, H. D.; Chang, A. T. C.

    1981-01-01

    Global maps of precipitable water over derived from scanning multichannel microwave radiometer (SMMR) data reveal salient features associated with ocean currents and the large scale general circulation in the atmosphere. Nimbus-7 SMMR brightness temperature measurements in the 21 and 18 GHz channels are used to sense the precipitable water in the atmospheric over oceans. The difference in the brightness temperature (T sub 21 -T sub 18), both in the horizontal and vertical polarization, is found to be essentially a function of the precipitable water in the atmosphere. An equation, based on the physical consideration of the radiative transfer in the microwave region, is developed to relate the precipitable water to (T sub 21 - T sub 18). It shows that the signal (T sub 21- T sub 18) does not suffer severely from the noise introduced by variations in the sea surface temperature, surface winds, and liquid water content in non rain clouds. The rms deviation between the estimated precipitable water from SMMR data and that given by the closely coincident ship radiosondes is about 0.25 g/ sq cm

  11. Effects of Faraday Rotation on Microwave Remote Sensing From Space at L-Band

    NASA Technical Reports Server (NTRS)

    LeVine, D. M.; Kao, M.

    1997-01-01

    The effect of Faraday rotation on the remote sensing of soil moisture from space is investigated using the International Reference Ionosphere (IRI) to obtain electron density profiles and the International Geomagnetic Reference Field (IGRF) to model the magnetic field. With a judicious choice of satellite orbit (6 am, sunsynchronous) the errors caused by ignoring Faraday rotation are less than 1 K at incidence angles less than 40 degrees.

  12. Monitoring boreal ecosystem phenology with integrated active/passive microwave remote sensing

    NASA Technical Reports Server (NTRS)

    McDonald, K. C.; Njoku, E.; Kimball, J.; Running, S.; Thompson, C.; Lee, J. K.

    2002-01-01

    The important role of the high latitudes in the functioning of global processes is becoming well established. The size and remoteness of arctic and boreal ecosystems, however, pose a challenge to quantification of both terrestrial ecosystem processes and their feedbacks to regional and global climate conditions. Boreal and arctic regions form a complex land cover mosaic where vegetation structure, condition and distribution are strongly regulated by environmental factors such as moisture availability, permafrost, growing season length, disturbance and soil nutrients.

  13. Simulations of emissivity in passive microwave remote sensing with three-dimensional numerical solutions of Maxwell equations and fast algorithm

    NASA Astrophysics Data System (ADS)

    Zhou, Lin

    In the first part of the work, we developed coding for large-scale computation to solve 3-dimensional microwave scattering problem. Maxwell integral equations are solved by using MoM with RWG basis functions in conjunction with fast computation algorithms. The cost-effective solutions of parallel and distributed simulation were implemented on a low cost PC cluster, which consists of 32 processors connected to a fast Ethernet switch. More than a million of surface current unknowns were solved at unprecedented speeds. Accurate simulations of emissivities and bistatic coefficients from ocean and soil were achieved. Exponential correlation function and ocean spectrum are implementd for generating soil and ocean surfaces. They have fine scale features with large rms slope. The results were justified by comparison with numerical results from original code, which is based on pulse basis function, and from analytic methods like SPM, and also with experiments. In the second part of the work, fully polarimetric microwave emissions from wind-generated foam-covered ocean surfaces were investigated. The foam is treated as densely packed air bubbles coated with thin seawater coating. The absorption, scattering and extinction coefficients were calculated by Monte Carlo simulations of solutionsof Maxwell equations of a collection of coated particles. The effects of boundary roughness of ocean surfaces were included by using the second-order small perturbation method (SPM) describing the reflection coefficients between foam and ocean. An empirical wave-number spectrum was used to represent the small-scale wind-generated sea surfaces. The theoretical results of four Stokes brightness temperatures with typical parameters of foam in passive remote sensing at 10.8 GHz, 19.0 GHz and 36.5 GHz were illustrated. The azimuth variations of polarimetric brightness temperature were calculated. Emission with various wind speed and foam layer thickness was studied. The results were also compared

  14. Satellite and airborne oil spill remote sensing: State of the art and application to the BP DeepWater Horizon oil spill

    USGS Publications Warehouse

    Leifer, I.; Clark, R.; Jones, C.; Holt, B.; Svejkovsky, J.; Swayze, G.

    2011-01-01

    The vast, persistent, and unconstrained oil release from the DeepWater Horizon (DWH) challenged the spill response, which required accurate quantitative oil assessment at synoptic and operational scales. Experienced observers are the mainstay of oil spill response. Key limitations are weather, scene illumination geometry, and few trained observers, leading to potential observer bias. Aiding the response was extensive passive and active satellite and airborne remote sensing, including intelligent system augmentation, reviewed herein. Oil slick appearance strongly depends on many factors like emulsion composition and scene geometry, yielding false positives and great thickness uncertainty. Oil thicknesses and the oil to water ratios for thick slicks were derived quantitatively with a new spectral library approach based on the shape and depth of spectral features related to C-H vibration bands. The approach used near infrared, imaging spectroscopy data from the AVIRIS (Airborne Visual/InfraRed Imaging Spectrometer) instrument on the NASA ER-2 stratospheric airplane. Extrapolation to the total slick used MODIS satellite visual-spectrum broadband data, which observes sunglint reflection from surface slicks; i.e., indicates the presence of oil and/or surfactant slicks. Oil slick emissivity is less than seawater's allowing MODIS thermal infrared (TIR) nighttime identification; however, water temperature variations can cause false positives. Some strong emissivity features near 6.7 and 9.7 ??m could be analyzed as for the AVIRIS short wave infrared features, but require high spectral resolution data. TIR spectral trends can allow fresh/weathered oil discrimination. Satellite Synthetic Aperture Radar (SSAR) provided synoptic data under all-sky conditions by observing oil dampening of capillary waves; however, SSAR typically cannot discriminate thick from thin oil slicks. Airborne UAVSAR's significantly greater signal-to-noise ratio and fine spatial resolution allowed

  15. The Passive Microwave Remote Sensing of Soil Moisture: the Effect of Tilled Row Structure

    NASA Technical Reports Server (NTRS)

    Wang, J. R.; Newton, R. W.; Rouse, J. W.

    1979-01-01

    The tilled rowstructure is known to be one of the important factors affecting the observations of the microwave emission from a natural surface. Measurements of this effect were carried out with both I and X band radiometers mounted on a mobile truck on a bare 40 m x 45 m row tilled field. The soil moisture content during the measurements ranged from approximately 10 percent to approximately 30 percent by dry weight. The results of these measurements showed that the variations of the antenna temperatures with incident angle theta changed with the azimuthal angle a measured from the row direction. A numerical calculation based on a composite surface roughness was made and found to predict the observed features within the model's limit of accuracy. It was concluded that the difference between the horizontally and vertically polarized temperatures was due to the change in the local angle of field emission within the antenna field of view caused by the large scale row structure.

  16. Recent glacier surface snowpack melt in Novaya Zemlya and Severnaya Zemlya derived from active and passive microwave remote sensing data

    NASA Astrophysics Data System (ADS)

    Zhao, Meng

    The warming rate in the Russian High Arctic (RHA) (36˜158°E, 73˜82°N) is outpacing the pan-Arctic average, and its effect on the small glaciers across this region needs further examination. The temporal variation and spatial distribution of surface melt onset date (MOD) and total melt days (TMD) throughout the Novaya Zemlya (NovZ) and Severnaya Zemlya (SevZ) archipelagoes serve as good indicators of ice mass ablation and glacier response to regional climate change in the RHA. However, due to the harsh environment, long-term glaciological observations are limited, necessitating the application of remotely sensed data to study the surface melt dynamics. The high sensitivity to liquid water and the ability to work without solar illumination and penetrate non-precipitating clouds make microwave remote sensing an ideal tool to detect melt in this region. This work extracts resolution-enhanced passive and active microwave data from different periods and retrieves a decadal melt record for NovZ and SevZ. The high correlation among passive and active data sets instills confidence in the results. The mean MOD is June 20th on SevZ and June 10th on NovZ during the period of 1992-2012. The average TMDs are 47 and 67 days on SevZ and NovZ from 1995 to 2011, respectively. NovZ had large interannual variability in the MOD, but its TMD generally increased. SevZ MOD is found to be positively correlated to local June reanalysis air temperature at 850hPa geopotential height and occurs significantly earlier (˜0.73 days/year, p-value < 0.01) from 1992 to 2011. SevZ also experienced a longer TMD trend (˜0.75 days/year, p-value < 0.05) from 1995 to 2011. Annual mean TMD on both islands are positively correlated with regional summer mean reanalysis air temperature and negatively correlated to local sea ice extent. These strong correlations might suggest that the Russian High Arctic glaciers are vulnerable to the continuously diminishing sea ice extent, the associated air temperature

  17. Modeling multi-layer effects in passive microwave remote sensing of dry snow using Dense Media Radiative Transfer Theory (DMRT) based on quasicrystalline approximation

    USGS Publications Warehouse

    Liang, D.; Xu, X.; Tsang, L.; Andreadis, K.M.; Josberger, E.G.

    2008-01-01

    The Dense Media Radiative Transfer theory (DMRT) of Quasicrystalline Approximation of Mie scattering by sticky particles is used to study the multiple scattering effects in layered snow in microwave remote sensing. Results are illustrated for various snow profile characteristics. Polarization differences and frequency dependences of multilayer snow model are significantly different from that of the single-layer snow model. Comparisons are also made with CLPX data using snow parameters as given by the VIC model. ?? 2007 IEEE.

  18. Fast Numerical Algorithms for 3-D Scattering from PEC and Dielectric Random Rough Surfaces in Microwave Remote Sensing

    NASA Astrophysics Data System (ADS)

    Zhang, Lisha

    We present fast and robust numerical algorithms for 3-D scattering from perfectly electrical conducting (PEC) and dielectric random rough surfaces in microwave remote sensing. The Coifman wavelets or Coiflets are employed to implement Galerkin's procedure in the method of moments (MoM). Due to the high-precision one-point quadrature, the Coiflets yield fast evaluations of the most off-diagonal entries, reducing the matrix fill effort from O(N2) to O( N). The orthogonality and Riesz basis of the Coiflets generate well conditioned impedance matrix, with rapid convergence for the conjugate gradient solver. The resulting impedance matrix is further sparsified by the matrix-formed standard fast wavelet transform (SFWT). By properly selecting multiresolution levels of the total transformation matrix, the solution precision can be enhanced while matrix sparsity and memory consumption have not been noticeably sacrificed. The unified fast scattering algorithm for dielectric random rough surfaces can asymptotically reduce to the PEC case when the loss tangent grows extremely large. Numerical results demonstrate that the reduced PEC model does not suffer from ill-posed problems. Compared with previous publications and laboratory measurements, good agreement is observed.

  19. Soil Moisture Retrieval Through Changing Corn Using Active/Passive Microwave Remote Sensing

    NASA Technical Reports Server (NTRS)

    ONeill, P. E.; Joseph, A.; DeLannoy, G.; Lang, R.; Utku, C.; Kim, E.; Houser, P.; Gish, T.

    2003-01-01

    An extensive field experiment was conducted from May-early October, 2002 at the heavily instrumented USDA-ARS (U.S. Dept. of Agriculture-Agricultural Research Service) OPE3 (Optimizing Production Inputs for Economic and Environmental Enhancement) test site in Beltsville, MD to acquire data needed to address active/passive microwave algorithm, modeling, and ground validation issues for accurate soil moisture retrieval. During the experiment, a tower-mounted 1.4 GHz radiometer (Lrad) and a truck-mounted dual-frequency (1.6 and 4.75 GHz) radar system were deployed on the northern edge of the site. The soil in this portion of the field is a sandy loam (silt 23.5%, sand 60.3%, clay 16.1%) with a measured bulk density of 1.253 g/cu cm. Vegetation cover in the experiment consisted of a corn crop which was measured from just after planting on April 17, 2002 through senescence and harvesting on October 2. Although drought conditions prevailed during the summer, the corn yield was near average, with peak biomass reached in late July.

  20. Airborne Multispectral and Thermal Remote Sensing for Detecting the Onset of Crop Stress Caused by Multiple Factors

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Remote sensing technology has been developed and applied to provide spatiotemporal information on crop stress for precision management. A series of multispectral images over a field planted cotton, corn and soybean were obtained by a Geospatial Systems MS4100 camera mounted on an Air Tractor 402B ai...

  1. Assessment of Superflux relative to fisheries research and monitoring. [airborne remote sensing of the Chesapeake bay plume and shelf regions

    NASA Technical Reports Server (NTRS)

    Thomas, J. P.

    1981-01-01

    Some of the findings of the Superflux program relative to fishery research and monitoring are reviewed. The actual and potential influences of the plume on the shelf ecosystem contiguous to the mouth of Chesapeake Bay are described and insights derived from the combined use of in situ and remotely sensed data are presented.

  2. SLAPex Freeze/Thaw 2015: The First Dedicated Soil Freeze/Thaw Airborne Campaign

    NASA Technical Reports Server (NTRS)

    Kim, Edward; Wu, Albert; DeMarco, Eugenia; Powers, Jarrett; Berg, Aaron; Rowlandson, Tracy; Freeman, Jacqueline; Gottfried, Kurt; Toose, Peter; Roy, Alexandre; Derksen, Chris; Royer, Alain; Belair, Stephane; Houser, Paul; McDonald, Kyle; Entin, Jared; Lewis, Kristen

    2016-01-01

    Soil freezing and thawing is an important process in the terrestrial water, energy, and carbon cycles, marking the change between two very different hydraulic, thermal, and biological regimes. NASA's Soil Moisture Active/Passive (SMAP) mission includes a binary freeze/thaw data product. While there have been ground-based remote sensing field measurements observing soil freeze/thaw at the point scale, and airborne campaigns that observed some frozen soil areas (e.g., BOREAS), the recently-completed SLAPex Freeze/Thaw (F/T) campaign is the first airborne campaign dedicated solely to observing frozen/thawed soil with both passive and active microwave sensors and dedicated ground truth, in order to enable detailed process-level exploration of the remote sensing signatures and in situ soil conditions. SLAPex F/T utilized the Scanning L-band Active/Passive (SLAP) instrument, an airborne simulator of SMAP developed at NASA's Goddard Space Flight Center, and was conducted near Winnipeg, Manitoba, Canada, in October/November, 2015. Future soil moisture missions are also expected to include soil freeze/thaw products, and the loss of the radar on SMAP means that airborne radar-radiometer observations like those that SLAP provides are unique assets for freeze/thaw algorithm development. This paper will present an overview of SLAPex F/T, including descriptions of the site, airborne and ground-based remote sensing, ground truth, as well as preliminary results.

  3. Predicting the aquatic stage sustainability of a restored backwater channel combining in-situ and airborne remotely sensed bathymetric models.

    NASA Astrophysics Data System (ADS)

    Jérôme, Lejot; Jérémie, Riquier; Hervé, Piégay

    2014-05-01

    As other large river floodplain worldwide, the floodplain of the Rhône has been deeply altered by human activities and infrastructures over the last centuries both in term of structure and functioning. An ambitious restoration plan of selected by-passed reaches has been implemented since 1999, in order to improve their ecological conditions. One of the main action aimed to increase the aquatic areas in floodplain channels (i.e. secondary channels, backwaters, …). In practice, fine and/or coarse alluvium were dredged, either locally or over the entire cut-off channel length. Sometimes the upstream or downstream alluvial plugs were also removed to reconnect the restored feature to the main channel. Such operation aims to restore forms and associated habitats of biotic communities, which are no more created or maintained by the river itself. In this context, assessing the sustainability of such restoration actions is a major issue. In this study, we focus on 1 of the 24 floodplain channels which have been restored along the Rhône River since 1999, the Malourdie channel (Chautagne reach, France). A monitoring of the geomorphologic evolution of the channel has been conducted during a decade to assess the aquatic stage sustainability of this former fully isolated channel, which has been restored as a backwater in 2004. Two main types of measures were performed: (a) water depth and fine sediment thickness were surveyed with an auger every 10 m along the channel centerline in average every year and a half allowing to establish an exponential decay model of terrestrialization rates through time; (b) three airborne campaigns (2006, 2007, 2012) by Ultra Aerial Vehicle (UAV) provided images from which bathymetry were inferred in combination with observed field measures. Coupling field and airborne models allows us to simulate different states of terrestrialization at the scale of the whole restore feature (e.g. 2020/2030/2050). Raw results indicate that terrestrialization

  4. Norwegian remote sensing experiment in a marginal ice zone

    USGS Publications Warehouse

    Farrelly, B.; Johannessen, J.A.; Svendsen, E.; Kloster, K.; Horjen, I.; Matzler, C.; Crawford, J.; Harrington, R.; Jones, L.; Swift, C.; Delnore, V.E.; Cavalieri, D.; Gloersen, P.; Hsiao, S.V.; Shemdin, O.H.; Thompson, T.W.; Ramseier, R.O.; Johannessen, O.M.; Campbell, W.J.

    1983-01-01

    The Norwegian Remote Sensing Experiment in the marginal ice zone north of Svalbard took place in fall 1979. Coordinated passive and active microwave measurements were obtained from shipborne, airborne, and satellite instruments together with in situ observations. The obtained spectra of emissivity (frequency range, 5 to 100 gigahertz) should improve identification of ice types and estimates of ice concentration. Mesoscale features along the ice edge were revealed by a 1.215-gigahertz synthetic aperture radar. Ice edge location by the Nimbus 7 scanning multichannel microwave radiometer was shown to be accurate to within 10 kilometers.

  5. Development of a one-dimensional electro-thermophysical model of the snow sea-ice system: Arctic climate processes and microwave remote sensing applications

    NASA Astrophysics Data System (ADS)

    Hanesiak, John Michael

    Snow covered sea ice plays a crucial role in the earth's climate. This includes polar biology, local, regional and world weather and ocean circulations as well as indigenous people's way of life. Recent research has indicated significant climate change in the polar regions, especially the Canadian arctic. Polar climate processes are also among the most poorly misrepresented within global circulation models (GCMs). The goal of this thesis is to improve our understanding and capability to simulate arctic climate processes in a predictive sense. An electro-thermophysical relationship exists between the thermophysical characteristics (climate variables and processes) and electrical properties (dielectrics) that control microwave remote sensing of snow-covered first- year sea ice (FYI). This work explicitly links microwave dielectrics and a thermodynamic model of snow and sea ice by addressing four key issues. These includes: (1)ensure the existing one-dimensional sea ice models treat the surface energy balance (SEB) and snow/ice thermodynamics in the appropriate time scales we see occurring in field experiments, (2)ensure the snow/ice thermodynamics are not compromised by differences in environmental and spatial representation within components of the SEB, (3)ensure the snow layer is properly handled in the modeling environment, and (4)how we can make use of satellite microwave remote sensing data within the model environment. Results suggest that diurnal processes are critical and need to be accounted for in modeling snow-covered FYI, similar to time scales acting in microwave remote sensing signatures. Output from the coupled snow sea-ice model provides the required input to microwave dielectric models of snow and sea ice to predict microwave penetration depths within the snow and sea ice (an Electro-Thermophysical model of the Snow Sea Ice System (ETSSIS)). Results suggest ETSSIS can accurately simulate microwave penetration depths in the cold dry snow season and

  6. Airborne remote sensing of spatiotemporal change (1955-2004) in indigenous and exotic forest cover in the Taita Hills, Kenya

    NASA Astrophysics Data System (ADS)

    Pellikka, Petri K. E.; Lötjönen, Milla; Siljander, Mika; Lens, Luc

    2009-08-01

    We studied changes in area and species composition of six indigenous forest fragments in the Taita Hills, Kenya using 1955 and 1995 aerial photography with 2004 airborne digital camera mosaics. The study area is part of Eastern Arc Mountains, a global biodiversity hot spot that boasts an outstanding diversity of flora and fauna and a high level of endemism. While a total of 260 ha (50%) of indigenous tropical cloud forest was lost to agriculture and bushland between 1955 and 2004, large-scale planting of exotic pines, eucalyptus, grevillea, black wattle and cypress on barren land during the same period resulted in a balanced total forest area. In the Taita Hills, like in other Afrotropical forests, indigenous forest loss may adversely affect ecosystem services.

  7. Development of a rainfall model to study rainfall over South Africa using satellite microwave remote sensing

    NASA Astrophysics Data System (ADS)

    Mishra, Anoop Kumar; Rawat, Kishan Singh

    2015-01-01

    In this study, a rainfall model is developed to study rainfall over South Africa (10° to 40°E, 35° to 20°S) using a set of rainfall signatures derived from Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) observations at 0.25 deg×0.25 deg spatial grid. Based on measurements at 19-, 21-, and 85-GHz channels of TMI, the scattering index (SI) is derived. Polarization corrected temperature (PCT) is calculated using measurements at the 85-GHz channel. SI, PCT, and their combinations are tested as rain signatures over South Africa. These rain signatures (i.e., PCT and SI and their combinations) are collocated against precipitation radar (PR) onboard TRMM to derive a relationship between rain rate and rain signatures. Rainfall retrieval is attempted using linear as well as nonlinear regressions. The results have been validated using an independent dataset of PR. It is reported that a nonlinear regression outperforms a linear algorithm. Statistical validation with an independent dataset of PR exhibits the correlation coefficients (CCs) of 0.60, 0.64, and 0.66, and root mean square errors (RMSEs) of 5.82, 6.42, and 5.76 mm/h from observations of SI, PCT, and a combination of SI and PCT, respectively, using linear regressions. When nonlinear regression is used, the CC of 0.69, 0.68, and 0.70 and RMSE of 4.75, 4.89, and 4.38 mm/h are observed from the SI, PCT, and the combination of SI and PCT, respectively.

  8. Model-estimated microwave emissions from rain systems for remote sensing applications

    NASA Astrophysics Data System (ADS)

    Smirnov, Mikhail T.; Meischner, Peter F.

    1996-12-01

    A simple model for estimating the upward and downward microwave emission from rain layer types above ground is presented. The emission properties of the rain layers are estimated from physical quantities such as the optical depth, the single-scattering albedo, the physical temperature, and a given drop size distribution for Mie scattering calculations. The underlying surface is characterized by the emissivity and the physical temperature. The transparency coefficient q and the reflection coefficient r of the rain layer are expressed by these physical quantities. The brightness temperature then is given by the physical temperature T, q, and r. The radiation transfer is estimated by the method of layer addition, described by Sobolev [1956], which avoids the necessity of solving the equation of radiation transfer. The accuracy of this simple model was estimated by comparisons with three-dimensional Monte Carlo calculations. The error is estimated to be less than 3 K for common situations and less than 8 K for unrealistic high optical depths. It is shown that any one of the quantities rain rate, rain layer depth, and physical temperature can be estimated with sufficient accuracy if the others are known. The basic model has been extended for application to inhomogeneous cloud layers and to include differences in brightness temperatures for horizontal and vertical polarizations for oblate raindrops. The main intended application of this model is rain rate estimation from space with low data processing efforts, especially for the Priroda mission. The model was tested for the downwelling emission during the field experiment CLEOPATRA by measurements with a polarimetric weather radar and rain gauges. The results verify the principles, and promising agreement was found at least for stratiform rain. The polarimetric extension of the model too showed promising results under quite different measurement conditions in Russia and southern Germany.

  9. Passive microwave remote sensing of rainfall with SSM/I: Algorithm development and implementation

    NASA Technical Reports Server (NTRS)

    Ferriday, James G.; Avery, Susan K.

    1994-01-01

    A physically based algorithm sensitive to emission and scattering is used to estimate rainfall using the Special Sensor Microwave/Imager (SSM/I). The algorithm is derived from radiative transfer calculations through an atmospheric cloud model specifying vertical distributions of ice and liquid hydrometeors as a function of rain rate. The algorithm is structured in two parts: SSM/I brightness temperatures are screened to detect rainfall and are then used in rain-rate calculation. The screening process distinguishes between nonraining background conditions and emission and scattering associated with hydrometeors. Thermometric temperature and polarization thresholds determined from the radiative transfer calculations are used to detect rain, whereas the rain-rate calculation is based on a linear function fit to a linear combination of channels. Separate calculations for ocean and land account for different background conditions. The rain-rate calculation is constructed to respond to both emission and scattering, reduce extraneous atmospheric and surface effects, and to correct for beam filling. The resulting SSM/I rain-rate estimates are compared to three precipitation radars as well as to a dynamically simulated rainfall event. Global estimates from the SSM/I algorithm are also compared to continental and shipboard measurements over a 4-month period. The algorithm is found to accurately describe both localized instantaneous rainfall events and global monthly patterns over both land and ovean. Over land the 4-month mean difference between SSM/I and the Global Precipitation Climatology Center continental rain gauge database is less than 10%. Over the ocean, the mean difference between SSM/I and the Legates and Willmott global shipboard rain gauge climatology is less than 20%.

  10. Overview Of Haze And Smoke Measurements in Northern High Latitudes And California During ARCTAS Using The NASA Ames Airborne Sunphotometer And Associated In Situ And Remote Sensors

    NASA Astrophysics Data System (ADS)

    Russell, P. B.; Redemann, J.; Livingston, J.; Shinozuka, Y.; Ramachandran, S.; Johnson, R. R.; Clarke, A. D.; Howell, S. G.; McNaughton, C.; Holben, B.; O'Neill, N.; McArthur, B.; Reid, E.; Ferrare, R. A.; Hostetler, C. A.

    2009-12-01

    The 14-channel NASA Ames Airborne Tracking Sunphotometer (AATS-14) operated in a suite of remote and in-situ sensors aboard the NASA P-3 aircraft during the 2008 Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) field campaign. Included were 8 Spring flights in the Arctic and 13 Summer flights (3 in California and 10 in Canada), each coordinated with one or more satellite overpasses, other aircraft (e.g., NASA B-200 and DC-8, NOAA P-3), and/or ground-based Aerosol Robotic Network (AERONET) measurements. This presentation gives an overview of AATS-14 aerosol optical depth (AOD) spectra and related parameters such as Angstrom exponent and fine mode fraction. We quantify the mutual consistency of AODs calculated from measurements by AATS-14, by the HiGEAR (University of Hawaii Group for Environmental Aerosol Research) suite of P-3 in-situ optical instruments, and by AERONET . The vertical integral of the HiGEAR in-situ scattering and absorption coefficients recorded during spiral profiles typically falls within 10% ± 0.02 of the AATS-14 AOD values interpolated to 450, 550 and 700 nm. Corresponding Angstrom exponents typically differ by ~0.1. AATS-14 AODs adjusted for the contribution of the layer below the aircraft (estimated with HiGEAR data) generally agree with the full column AERONET values to within the combined uncertainties. Example results from multi-platform comparisons are also shown. These results provide context for the more detailed AATS-14 results in other presentations, e.g., by Redemann et al. (focusing on the multi-platform, multi-sensor smoke case of 30 Jun 2008), Livingston et al. (comparisons to MODIS, MISR, OMI, POLDER, CALIPSO, and airborne lidar), and Shinozuka et al. (relationship to cloud condensation nuclei and other measurements).

  11. Tropospheric Passive Remote Sensing

    NASA Technical Reports Server (NTRS)

    Keafer, L. S., Jr. (Editor)

    1982-01-01

    The long term role of airborne/spaceborne passive remote sensing systems for tropospheric air quality research and the identification of technology advances required to improve the performance of passive remote sensing systems were discussed.

  12. Remotely sensed transport in microwave photoexcited GaAs/AlGaAs two-dimensional electron system

    NASA Astrophysics Data System (ADS)

    Ye, Tianyu; Mani, R. G.; Wegscheider, W.

    2013-06-01

    We demonstrate a strong correlation between the magnetoresistive response and the concurrent microwave reflection from the microwave photo-excited GaAs/AlGaAs two-dimensional electron system (2DES). These correlations are followed as a function of the microwave power, the microwave frequency, and the applied current. Notably, the character of the reflection signal remains unchanged even when the current is switched off in the GaAs/AlGaAs Hall bar specimen. The results suggest a perceptible microwave-induced change in the electronic properties of the 2DES, even in the absence of an applied current.

  13. Assessment of Superflux relative to marine science and oceanography. [airborne remote sensing of the Chesapeake Bay plume and shelf regions

    NASA Technical Reports Server (NTRS)

    Esaias, W. E.

    1981-01-01

    A general assessment of the Superflux project is made in relation to marine science and oceanography. It is commented that the program clearly demonstrated the effectiveness of state-of-the-art technology required to study highly dynamic estuarine plumes, and the necessity of a broadly interdisciplinary, interactive remote sensing and shipboard program required to significantly advance the understanding of transport processes and impacts of estuarine outflows.

  14. Evaluation of Surface Energy Balance models for mapping evapotranspiration using very high resolution airborne remote sensing data

    NASA Astrophysics Data System (ADS)

    Paul, George

    Agriculture is the largest (90%) consumer of all fresh water in the world. The consumptive use of water by vegetation represented by the process evapotranspiration (ET) has a vital role in the dynamics of water, carbon and energy fluxes of the biosphere. Consequently, mapping ET is essential for making water a sustainable resource and also for monitoring ecosystem response to water stress and changing climate. Over the past three decades, numerous thermal remote sensing based ET mapping algorithms were developed and these have brought a significant theoretical and technical advancement in the spatial modeling of ET. Though these algorithms provided a robust, economical, and efficient tool for ET estimations at field and regional scales, yet the uncertainties in flux estimations were large, making evaluation a difficult task. The main objective of this study was to evaluate and improve the performance of widely used remote sensing based energy balance models, namely: the Surface Energy Balance Algorithm for Land (SEBAL), Mapping Evapotranspiration at high Resolution and with Internalized Calibration (METRIC), and Surface Energy Balance System (SEBS). Data used in this study was collected as part of a multi-disciplinary and multi-institutional field campaign BEAREX (Bushland Evapotranspiration and Agricultural Remote Sensing Experiment) that was conducted during 2007 and 2008 summer cropping seasons at the USDA-ARS Conservation and Production Research Laboratory (CPRL) in Bushland, Texas. Seventeen high resolution remote sensing images taken from multispectral sensors onboard aircraft and field measurements of the agro-meteorological variables from the campaign were used for model evaluation and improvement. Overall relative error measured in terms of mean absolute percent difference (MAPD) for instantaneous ET (mm h -1) were 22.7%, 23.2%, and 12.6% for SEBAL, METRIC, and SEBS, respectively. SEBAL and METRIC performances for irrigated fields representing higher ET

  15. Investigation of Arctic mixed-phase clouds by combining airborne remote sensing and in situ observations during VERDI, RACEPAC and ACLOUD

    NASA Astrophysics Data System (ADS)

    Ehrlich, André; Bierwirth, Eike; Borrmann, Stephan; Crewell, Susanne; Herber, Andreas; Hoor, Peter; Jourdan, Olivier; Krämer, Martina; Lüpkes, Christof; Mertes, Stephan; Neuber, Roland; Petzold, Andreas; Schnaiter, Martin; Schneider, Johannes; Weigel, Ralf; Weinzierl, Bernadett; Wendisch, Manfred

    2016-04-01

    To improve our understanding of Arctic mixed-phase clouds a series of airborne research campaigns has been initiated by a collaboration of German research institutes. Clouds in areas dominated by a close sea-ice cover were observed during the research campaign Vertical distribution of ice in Arctic mixed-phase clouds (VERDI, April/May 2012) and the Radiation-Aerosol-Cloud Experiment in the Arctic Circle (RACEPAC, April/May 2014) which both were based in Inuvik, Canada. The aircraft (Polar 5 & 6, Basler BT-67) operated by the Alfred Wegener Institute for Polar and Marine Research, Germany did cover a wide area above the Canadian Beaufort with in total 149 flight hours (62h during VERDI, 87h during RACEPAC). For May/June 2017 a third campaign ACLOUD (Arctic Clouds - Characterization of Ice, aerosol Particles and Energy fluxes) with base in Svalbard is planned within the Transregional Collaborative Research Centre TR 172 ArctiC Amplification: Climate Relevant Atmospheric and SurfaCe Processes, and Feedback Mechanisms (AC)3 to investigate Arctic clouds in the transition zone between open ocean and sea ice. The aim of all campaigns is to combine remote sensing and in-situ cloud, aerosol and trace gas measurements to investigate interactions between radiation, cloud and aerosol particles. While during VERDI remote sensing and in-situ measurements were performed by one aircraft subsequently, for RACEPAC and ACLOUD two identical aircraft are coordinated at different altitudes to horizontally collocate both remote sensing and in-situ measurements. The campaign showed that in this way radiative and microphysical processes in the clouds can by studied more reliably and remote sensing methods can be validated efficiently. Here we will illustrate the scientific strategy of the projects including the progress in instrumentation. Differences in the general synoptic and sea ice situation and related changes in cloud properties at the different locations and seasons will be

  16. The Relationship Between Fossil and Dairy Greenhouse Gas Emissions and Complex Urban Land-Use Patterns by In Situ and Remote Sensing Data from Surface Mobile, Airborne, and Satellite Instruments

    NASA Astrophysics Data System (ADS)

    Leifer, I.; Melton, C.; Tratt, D. M.; Kuze, A.; Buckland, K. N.; Butz, A.; Deguchi, A.; Eastwood, M. L.; Fischer, M. L.; Frash, J.; Fladeland, M. M.; Gore, W.; Iraci, L. T.; Johnson, P. D.; Kataoka, F.; Kolyer, R.; Leen, J. B.; Quattrochi, D. A.; Shiomi, K.; Suto, H.; Tanaka, T.; Thompson, D. R.; Yates, E. L.; Van Damme, M.; Yokota, T.

    2015-12-01

    The GOSAT-COMEX-IASI Experiment (Greenhouse gases Observing SATellite-CO2and Methane EXperiment) demonstrated a novel approach to airborne-surface mobile in situ data fusion for interpretation and validation of satellite and airborne remote sensing data of greenhouse gases and direct calculation of flux. Key data were collected for the Chino Dairy in the Los Angeles Basin, California and for the Kern River Oil Fields adjacent to Bakersfield, California. In situ surface and remote sensing greenhouse gas and ammonia observations were compared with IASI and GOSAT retreivals, while hyperspectral imaging data from the AVIRIS, AVIRIS NG, and Mako airborne sensors were analyzed to relate emissions and land use. Figure - platforms participating in the experiment. TANSO-FTS aboard the Ibuki satellite (GOSAT) provided targeted pixels to measure column greenhouse gases. AMOG is the AutoMObile Gas Surveyor which supports a suite of meteorology and in situ trace gas sensors for mobile high speed measurement. AVIRIS, the Airborne Visual InfraRed Imaging Spectrometer aboard the NASA ER-2 airplane collected hyperspectral imaging data at 20 m resolution from 60,000 ft. Mako is a thermal infrared imaging spectrometer that was flown on the Twin Otter International. AJAX is a fighter jet outfitted for science sporting meteorology and greenhouse gas sensors. RAMVan is an upward looking FTIR for measuring column methane and ammonia and other trace gases.

  17. Comparison of Reflected Solar Radiance Using Aqua Modis and Airborne Remote Sensing (case : Deep Convective Clouds and Cirrus Clouds)

    NASA Astrophysics Data System (ADS)

    Krisna, T. C.; Ehrlich, A.; Werner, F.; Wendisch, M.

    2015-12-01

    Deep Convective Clouds (DCCs) have key role in the tropical region. Despite they only have small spatial coverage, but they account most of the total precipitation in these region which often make flooding. There are such of aviation accidents caused by strong vertical wind, hailing, icing and lightning inside the clouds. Pollutions caused by biomass burning and land degradation can change the aerosol properties as well as cloud properties, therefore will influence the radiation and formation of the DCCs. Those are the major reasons that better understanding of DCCs formation and life cycle are necessary. Between Sept. 01 - Oct. 14, ACRIDICON (Aerosol, Cloud, Precipitation, and Radiation Interactions and Dynamics of Concevtive Clouds Systems) campaign was conducted over Amazonia. It is suitable area to be the site-study due to has strong contrast environtment (pristine and polluted), regular convection activities and stable meteorological condition. In this study we focus on the 2 satellite validation missions designed to fly collocated but in different altitude with A-TRAIN constellation. In order to study DCCs-solar radiation interaction, we use SMART (Spectral Modular Airborne Radiation Measurements System) installed on HALO (High Altitude and Long-Range Research Aircraft) which measures spectral Irradiance (F) and Radiance (I) at the wavelength between 300-2200 nm corresponding to satellite. Due to the limitation in spatial and temporal, airborne measurements only give snapshots of atmosphere condition and DCCs formation, therefore we use multi-satellite data as DCCs have high vertical and horizontal distance, long temporal development and complex form. The comparison of AQUA MODIS and SMART Radiance at 645 nm (non-absorbing) in the clear-sky condition gives strong agreement, but in the multilayer-cloud condition gives worse and results in high underestimation (-86%) in SMART data especially at lower altitude. The bias is caused by interference from clouds

  18. Remote Sensing of Multi-Level Wind Fields with High-Energy Airborne Scanning Coherent Doppler Lidar

    NASA Technical Reports Server (NTRS)

    Rothermel, Jeffry; Olivier, Lisa D.; Banta, Robert M.; Hardesty, R. Michael; Howell, James N.; Cutten, Dean R.; Johnson, Steven C.; Menzies, Robert T.; Tratt, David M.

    1997-01-01

    The atmospheric lidar remote sensing groups of NOAA Environmental Technology Laboratory, NASA Marshall Space Flight Center, and Jet Propulsion Laboratory have developed and flown a scanning, 1 Joule per pulse, CO2 coherent Doppler lidar capable of mapping a three-dimensional volume of atmospheric winds and aerosol backscatter in the troposphere and lower stratosphere. Applications include the study of severe and non-severe atmospheric flows, intercomparisons with other sensors, and the simulation of prospective satellite Doppler lidar wind profilers. Examples of wind measurements are given for the marine boundary layer and near the coastline of the western United States.

  19. Modeling of mean radiant temperature based on comparison of airborne remote sensing data with surface measured data

    NASA Astrophysics Data System (ADS)

    Chen, Yu-Cheng; Chen, Chih-Yu; Matzarakis, Andreas; Liu, Jin-King; Lin, Tzu-Ping

    2016-06-01

    Assessment of outdoor thermal comfort is becoming increasingly important due to the urban heat island effect, which strongly affects the urban thermal environment. The mean radiant temperature (Tmrt) quantifies the effect of the radiation environment on humans, but it can only be estimated based on influencing parameters and factors. Knowledge of Tmrt is important for quantifying the heat load on human beings, especially during heat waves. This study estimates Tmrt using several methods, which are based on climatic data from a traditional weather station, microscale ground surface measurements, land surface temperature (LST) and light detection and ranging (LIDAR) data measured using airborne devices. Analytical results reveal that the best means of estimating Tmrt combines information about LST and surface elevation information with meteorological data from the closest weather station. The application in this method can eliminate the inconvenience of executing a wide range ground surface measurement, the insufficient resolution of satellite data and the incomplete data of current urban built environments. This method can be used to map a whole city to identify hot spots, and can be contributed to understanding human biometeorological conditions quickly and accurately.

  20. Extending airborne electromagnetic surveys for regional active layer and permafrost mapping with remote sensing and ancillary data, Yukon Flats ecoregion, central Alaska

    USGS Publications Warehouse

    Pastick, Neal J.; Jorgenson, M. Torre; Wylie, Bruce K.; Minsley, Burke J.; Ji, Lei; Walvoord, Michelle A.; Smith, Bruce D.; Abraham, Jared D.; Rose, Joshua R.

    2013-01-01

    Machine-learning regression tree models were used to extrapolate airborne electromagnetic resistivity data collected along flight lines in the Yukon Flats Ecoregion, central Alaska, for regional mapping of permafrost. This method of extrapolation (r = 0.86) used subsurface resistivity, Landsat Thematic Mapper (TM) at-sensor reflectance, thermal, TM-derived spectral indices, digital elevation models and other relevant spatial data to estimate near-surface (0–2.6-m depth) resistivity at 30-m resolution. A piecewise regression model (r = 0.82) and a presence/absence decision tree classification (accuracy of 87%) were used to estimate active-layer thickness (ALT) (< 101 cm) and the probability of near-surface (up to 123-cm depth) permafrost occurrence from field data, modelled near-surface (0–2.6 m) resistivity, and other relevant remote sensing and map data. At site scale, the predicted ALTs were similar to those previously observed for different vegetation types. At the landscape scale, the predicted ALTs tended to be thinner on higher-elevation loess deposits than on low-lying alluvial and sand sheet deposits of the Yukon Flats. The ALT and permafrost maps provide a baseline for future permafrost monitoring, serve as inputs for modelling hydrological and carbon cycles at local to regional scales, and offer insight into the ALT response to fire and thaw processes.

  1. Case studies of aerosol remote sensing with the Airborne Multiangle SpectroPolarimetric Imager (AirMSPI)

    NASA Astrophysics Data System (ADS)

    Diner, D. J.; Xu, F.; Garay, M. J.; Martonchik, J. V.; Kalashnikova, O. V.; Davis, A. B.; Rheingans, B.; Geier, S.; Jovanovic, V.; Bull, M.

    2012-12-01

    The Airborne Multiangle SpectroPolarimetric Imager (AirMSPI) is an 8-band (355, 380, 445, 470, 555, 660, 865, 935 nm) pushbroom camera, measuring polarization in the 470, 660, and 865 nm bands, mounted on a gimbal to acquire multiangular observations over a ±67° along-track range with 10-m spatial resolution across an 11-km wide swath. Among the instrument objectives are exploration of methodologies for combining multiangle, multispectral, polarimetric, and imaging observations to retrieve the optical depth and microphysical properties of tropospheric aerosols. AirMSPI was integrated on NASA's ER-2 high-altitude aircraft in 2010 and has successfully completed a number of flights over land and ocean targets in the Southern California vicinity. In this paper, we present case studies of AirMSPI imagery, interpreted using vector radiative transfer theory. AirMSPI observations over California's Central Valley are compared with model calculations using aerosol properties reported by the Fresno AERONET sunphotometer. Because determination of the radiative impact of different types of aerosols requires accurate attribution of the source of the reflected light along with characterization of the aerosol optical and microphysical properties, we explore the sensitivity of the Fresno measurements to variations in different aerosol properties, demonstrating the value of combining intensity and polarimetry at multiple view angles and spectral bands for constraining particle microphysical properties. Images over ocean to be presented include scenes over nearly cloud-free skies and scenes containing scattered clouds. It is well known that imperfect cloud screening confounds the determination of aerosol impact on radiation; it is perhaps less well appreciated that the effect of cloud reflections in the water can also be problematic. We calculate the magnitude of this effect in intensity and polarization and discuss its potential impact on aerosol retrievals, underscoring the value

  2. Analysis of airborne particulate matter (PM2.5) over Hong Kong using remote sensing and GIS.

    PubMed

    Shi, Wenzhong; Wong, Man Sing; Wang, Jingzhi; Zhao, Yuanling

    2012-01-01

    Airborne fine particulates (PM(2.5); particulate matter with diameter less than 2.5 μm) are receiving increasing attention for their potential toxicities and roles in visibility and health. In this study, we interpreted the behavior of PM(2.5) and its correlation with meteorological parameters in Hong Kong, during 2007-2008. Significant diurnal variations of PM(2.5) concentrations were observed and showed a distinctive bimodal pattern with two marked peaks during the morning and evening rush hour times, due to dense traffic. The study observed higher PM(2.5) concentrations in winter when the northerly and northeasterly winds bring pollutants from the Chinese mainland, whereas southerly monsoon winds from the sea bring fresh air to the city in summer. In addition, higher concentrations of PM(2.5) were observed in rush hours on weekdays compared to weekends, suggesting the influence of anthropogenic activities on fine particulate levels, e.g., traffic-related local PM(2.5) emissions. To understand the spatial pattern of PM(2.5) concentrations in the context of the built-up environment of Hong Kong, we utilized MODerate Resolution Imaging Spectroradiometer (MODIS) Aerosol Optical Thickness (AOT) 500 m data and visibility data to derive aerosol extinction profile, then converted to aerosol and PM(2.5) vertical profiles. A Geographic Information Systems (GIS) prototype was developed to integrate atmospheric PM(2.5) vertical profiles with 3D GIS data. An example of the query function in GIS prototype is given. The resulting 3D database of PM(2.5) concentrations provides crucial information to air quality regulators and decision makers to comply with air quality standards and in devising control strategies.

  3. Vertical mass impact and features of Saharan dust intrusions derived from ground-based remote sensing in synergy with airborne in-situ measurements

    NASA Astrophysics Data System (ADS)

    Córdoba-Jabonero, Carmen; Andrey-Andrés, Javier; Gómez, Laura; Adame, José Antonio; Sorribas, Mar; Navarro-Comas, Mónica; Puentedura, Olga; Cuevas, Emilio; Gil-Ojeda, Manuel

    2016-10-01

    A study of the vertical mass impact of Saharan dust intrusions is presented in this work. Simultaneous ground-based remote-sensing and airborne in-situ measurements performed during the AMISOC-TNF campaign over the Tenerife area (Canary Islands) in summertime from 01 July to 11 August 2013 were used for that purpose. A particular dusty (DD) case, associated to a progressively arriving dust intrusion lasting for two days on 31 July (weak incidence) and 01 August (strong incidence), is especially investigated. AERONET AOD and AEx values were ranging, respectively, from 0.2 to 1.4 and 0.35 to 0.05 along these two days. Vertical particle size distributions within fine and coarse modes (0.16-2.8 μm range) were obtained from aircraft aerosol spectrometer measurements. Extinction profiles and Lidar Ratio (LR) values were derived from MPLNET/Micro Pulse Lidar observations. MAXDOAS measurements were also used to retrieve the height-resolved aerosol extinction for evaluation purposes in comparison to Lidar-derived profiles. The synergy between Lidar observations and airborne measurements is established in terms of the Mass Extinction Efficiency (MEE) to calculate the vertical mass concentration of Saharan dust particles. Both the optical and microphysical profilings show dust particles mostly confined in a layer of 4.3 km thickness from 1.7 to 6 km height. LR ranged between 50 and 55 sr, typical values for Saharan dust particles. In addition, this 2-day dust event mostly affected the Free Troposphere (FT), being less intense in the Boundary Layer (BL). In particular, rather high Total Mass Concentrations (TMC) were found on the stronger DD day (01 August 2013): 124, 70 and 21 μg m-3 were estimated, respectively, at FT and BL altitudes and on the near-surface level. This dust impact was enhanced due to the increase of large particles affecting the FT, but also the BL, likely due to their gravitational settling. However, the use of an assumed averaged MEE value can be

  4. Data Management Challenges for Airborne NASA Earth Venture Sub-Orbital (EVS-1) Investigations

    NASA Astrophysics Data System (ADS)

    Boyer, A.; Cook, R. B.; Santhana Vannan, S. K.

    2014-12-01

    The ORNL DAAC is developing a technology infrastructure to archive airborne remote sensing observations from two Earth System Science Pathfinder Missions. The two missions are CARVE: Carbon in Arctic Reservoirs Vulnerability Experiment and AirMOSS: Airborne Microwave Observatory of Subcanopy and Subsurface. The two missions are collecting over 140 TB of data from extensive ground-based and airborne instruments. The metadata and documentation requirements necessary for proper archive and dissemination of such transect-based, and often 3-dimensional, airborne data are quite different from the traditional field campaign and satellite remote sensing data streams. Staff at the ORNL DAAC are currently working with the CARVE and AirMOSS teams as well as investigating cyberinfrastructures from other DAACs to develop a metadata and data infrastructure for airborne data that will enable spatial, flight-line, or keyword-based search and discovery, integration as needed of related satellite- and ground-based data sets, and subsetting and visualization tools for both CARVE and AirMOSS. We discuss challenges, progress, and lessons learned.

  5. Airborne multispectral and thermal remote sensing for detecting the onset of crop stress caused by multiple factors

    NASA Astrophysics Data System (ADS)

    Huang, Yanbo; Thomson, Steven J.

    2010-10-01

    Remote sensing technology has been developed and applied to provide spatiotemporal information on crop stress for precision management. A series of multispectral images over a field planted cotton, corn and soybean were obtained by a Geospatial Systems MS4100 camera mounted on an Air Tractor 402B airplane equipped with Camera Link in a Magma converter box triggered by Terraverde Dragonfly® flight navigation and imaging control software. The field crops were intentionally stressed by applying glyphosate herbicide via aircraft and allowing it to drift near-field. Aerial multispectral images in the visible and near-infrared bands were manipulated to produce vegetation indices, which were used to quantify the onset of herbicide induced crop stress. The vegetation indices normalized difference vegetation index (NDVI) and soil adjusted vegetation index (SAVI) showed the ability to monitor crop response to herbicide-induced injury by revealing stress at different phenological stages. Two other fields were managed with irrigated versus nonirrigated treatments, and those fields were imaged with both the multispectral system and an Electrophysics PV-320T thermal imaging camera on board an Air Tractor 402B aircraft. Thermal imagery indicated water stress due to deficits in soil moisture, and a proposed method of determining crop cover percentage using thermal imagery was compared with a multispectral imaging method. Development of an image fusion scheme may be necessary to provide synergy and improve overall water stress detection ability.

  6. Is the Wilkins Ice Shelf a Firn Aquifer? Spaceborne Observation of Subsurface Winter Season Liquid Meltwater Storage on the Antarctic Peninsula using Multi-Frequency Active and Passive Microwave Remote Sensing

    NASA Astrophysics Data System (ADS)

    Miller, J.; Scambos, T.; Forster, R. R.; Long, D. G.; Ligtenberg, S.; van den Broeke, M.; Vaughan, D. G.

    2015-12-01

    Near-surface liquid meltwater on ice shelves has been inferred to influence ice shelf stability if it induces hydrofracture and is linked to disintegration events on the Larsen B and the Wilkins ice shelves on the Antarctic Peninsula during the summer months. While the initial Wilkins disintegration event occurred in March of 2009, two smaller disintegration events followed in May and in July of that year. It has long been assumed meltwater refreezes soon after surface melt processes cease. Given this assumption, an earlier hypothesis for the two winter season disintegration events was hydrofracture via a brine infiltration layer. Two lines of evidence supported this hypothesis 1) early airborne radar surveys did not record a reflection from the bottom of the ice shelf, and 2) a shallow core drilled in 1972 on the Wilkins encountered liquid water at a depth of ~7 m. The salinity of the water and the temperature at the base of the core, however, were not described. The recent discovery of winter season liquid meltwater storage on the Greenland ice sheet has changed perceptions on meltwater longevity at depth in firn. Evidence of Greenland's firn aquifer includes liquid meltwater encountered in shallow firn cores at 5 m depth and a lack of reflections from the base of the ice sheet in airborne surveys. Thus, previous lines of evidence suggesting brine infiltration may alternatively suggest the presence of a perennial firn aquifer. We recently demonstrated the capability for observation of Greenland's firn aquifer from space using multi-frequency active and passive microwave remote sensing. This research exploits the retrieval technique developed for Greenland to provide the first spaceborne mappings of winter season liquid meltwater storage on the Wilkins. We combine L-band brightness temperature and backscatter data from the MIRAS instrument (1.4 GHz) aboard ESA's Soil Moisture and Ocean Salinity mission and the radar (1.3 GHZ) and radiometer(1.4 GHz) aboard NASA

  7. Environmental hazards and distribution of radioactive black sand along the Rosetta coastal zone in Egypt using airborne spectrometric and remote sensing data.

    PubMed

    Kaiser, M F; Aziz, A M; Ghieth, B M

    2014-11-01

    High-resolution airborne gamma ray spectrometry, conducted in 2003, was used to estimate radioactive elements spatial abundance along the Rosetta coastal zone area. It was noticed that both Uranium and Thorium are concentrated in the black sand deposits along the beach. In contrary, Potassium was observed in high level abundance at the cultivated Nile Delta lands due to the accumulated usage of fertilizers. Exposure Rate (ER), Absorbed Dose Rate (ADR) and Annual Effective Dose Rate (AEDR) were calculated to evaluate the radiation background influence in human. Results indicated that the human body in the study sites is subjected to radiation hazards exceeds the accepted limit for long duration exposure. In addition, the areas covered by the highest concentration of Uranium and Thorium show the highest level of radiogenic heat production. Detection the environmental hazards of the radioactive black sands in the study site encouraged this research to monitor the spatial and temporal distribution of these sediments. The Landsat Thematic Mapper images acquired in 1990, 2003 and 2013 were analyzed using remote sensing image processing techniques. Image enhancements, classification and changes detection indicated a positive significant relationship between the patterns of coastline changes and distribution of the radioactive black sand in the study sites. The radioactive black sands are usually concentrated in the eroded areas. Therefore, in 1990 high concentration of the radioactive black sands were observed along the eastern and western flanks of the Rosetta promontory. Distribution of these sediments decreased due to the construction of the protective sea walls. Most of the radioactive black sands are transported toward the east in Abu Khashaba bay under the effect of the longshore currents and toward the west in Alexandria and Abu Quir bay under the action of the seasonal reverse currents.

  8. Extrapolation of in situ data from 1-km squares to adjacent squares using remote sensed imagery and airborne lidar data for the assessment of habitat diversity and extent.

    PubMed

    Lang, M; Vain, A; Bunce, R G H; Jongman, R H G; Raet, J; Sepp, K; Kuusemets, V; Kikas, T; Liba, N

    2015-03-01

    Habitat surveillance and subsequent monitoring at a national level is usually carried out by recording data from in situ sample sites located according to predefined strata. This paper describes the application of remote sensing to the extension of such field data recorded in 1-km squares to adjacent squares, in order to increase sample number without further field visits. Habitats were mapped in eight central squares in northeast Estonia in 2010 using a standardized recording procedure. Around one of the squares, a special study site was established which consisted of the central square and eight surrounding squares. A Landsat-7 Enhanced Thematic Mapper Plus (ETM+) image was used for correlation with in situ data. An airborne light detection and ranging (lidar) vegetation height map was also included in the classification. A series of tests were carried out by including the lidar data and contrasting analytical techniques, which are described in detail in the paper. Training accuracy in the central square varied from 75 to 100 %. In the extrapolation procedure to the surrounding squares, accuracy varied from 53.1 to 63.1 %, which improved by 10 % with the inclusion of lidar data. The reasons for this relatively low classification accuracy were mainly inherent variability in the spectral signatures of habitats but also differences between the dates of imagery acquisition and field sampling. Improvements could therefore be made by better synchronization of the field survey and image acquisition as well as by dividing general habitat categories (GHCs) into units which are more likely to have similar spectral signatures. However, the increase in the number of sample kilometre squares compensates for the loss of accuracy in the measurements of individual squares. The methodology can be applied in other studies as the procedures used are readily available. PMID:25648761

  9. A13K-0336: Airborne Multi-Wavelength High Spectral Resolution Lidar for Process Studies and Assessment of Future Satellite Remote Sensing Concepts

    NASA Technical Reports Server (NTRS)

    Hostetler, Chris A.; Ferrare, Rich A.; Hair, Johnathan W.; Cook, Anthony L.; Harper, David B.; Mack, Terry L.; Hare, Richard J.; Cleckner, Craig S.; Rogers, Raymond R.; Muller, Detlef; Chemyakin, Eduard; Burton, Sharon P.; Obland, Michael D.; Scarino, Amy J.; Cairns, Brian; Russell, Phil; Redermann, Jens; Shinozuka, Y.; Schmid, Beat; Fast, Jerome; Berg, Larry; Flynn, Connor; Wagener, Rick; Gregory, Laurie

    2012-01-01

    NASA Langley recently developed the world's first airborne multi-wavelength high spectral resolution lidar (HSRL). This lidar employs the HSRL technique at 355 and 532 nm to make independent, unambiguous retrievals of aerosol extinction and backscatter. It also employs the standard backscatter technique at 1064 nm and is polarization-sensitive at all three wavelengths. This instrument, dubbed HSRL-2 (the secondgeneration HSRL developed by NASA Langley), is a prototype for the lidar on NASA's planned Aerosols- Clouds-Ecosystems (ACE) mission. HSRL-2 completed its first science mission in July 2012, the Two-Column Aerosol Project (TCAP) conducted by the Department of Energy (DOE) in Hyannis, MA. TCAP presents an excellent opportunity to assess some of the remote sensing concepts planned for ACE: HSRL-2 was deployed on the Langley King Air aircraft with another ACE-relevant instrument, the NASA GISS Research Scanning Polarimeter (RSP), and flights were closely coordinated with the DOE's Gulfstream-1 aircraft, which deployed a variety of in situ aerosol and trace gas instruments and the new Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR). The DOE also deployed their Atmospheric Radiation Measurement Mobile Facility and their Mobile Aerosol Observing System at a ground site located on the northeastern coast of Cape Cod for this mission. In this presentation we focus on the capabilities, data products, and applications of the new HSRL-2 instrument. Data products include aerosol extinction, backscatter, depolarization, and optical depth; aerosol type identification; mixed layer depth; and rangeresolved aerosol microphysical parameters (e.g., effective radius, index of refraction, single scatter albedo, and concentration). Applications include radiative closure studies, studies of aerosol direct and indirect effects, investigations of aerosol-cloud interactions, assessment of chemical transport models, air quality studies, present (e.g., CALIPSO

  10. An algorithm for the estimation of bounds on the emissivity and temperatures from thermal multispectral airborne remotely sensed data

    NASA Technical Reports Server (NTRS)

    Jaggi, S.; Quattrochi, D.; Baskin, R.

    1992-01-01

    The effective flux incident upon the detectors of a thermal sensor, after it has been corrected for atmospheric effects, is a function of a non-linear combination of the emissivity of the target for that channel and the temperature of the target. The sensor system cannot separate the contribution from the emissivity and the temperature that constitute the flux value. A method that estimates the bounds on these temperatures and emissivities from thermal data is described. This method is then tested with remotely sensed data obtained from NASA's Thermal Infrared Multispectral Scanner (TIMS) - a 6 channel thermal sensor. Since this is an under-determined set of equations i.e. there are 7 unknowns (6 emissivities and 1 temperature) and 6 equations (corresponding to the 6 channel fluxes), there exist theoretically an infinite combination of values of emissivities and temperature that can satisfy these equations. Using some realistic bounds on the emissivities, bounds on the temperature are calculated. These bounds on the temperature are refined to estimate a tighter bound on the emissivity of the source. An error analysis is also carried out to quantitatively determine the extent of uncertainty introduced in the estimate of these parameters. This method is useful only when a realistic set of bounds can be obtained for the emissivities of the data. In the case of water the lower and upper bounds were set at 0.97 and 1.00 respectively. Five flights were flown in succession at altitudes of 2 km (low), 6 km (mid), 12 km (high), and then back again at 6 km and 2 km. The area selected with the Ross Barnett reservoir near Jackson, Mississippi. The mission was flown during the predawn hours of 1 Feb. 1992. Radiosonde data was collected for that duration to profile the characteristics of the atmosphere. Ground truth temperatures using thermometers and radiometers were also obtained over an area of the reservoir. The results of two independent runs of the radiometer data averaged

  11. Airborne rain mapping radar

    NASA Technical Reports Server (NTRS)

    Wilson, W. J.; Parks, G. S.; Li, F. K.; Im, K. E.; Howard, R. J.

    1988-01-01

    An airborne scanning radar system for remote rain mapping is described. The airborne rain mapping radar is composed of two radar frequency channels at 13.8 and 24.1 GHz. The radar is proposed to scan its antenna beam over + or - 20 deg from the antenna boresight; have a swath width of 7 km; a horizontal spatial resolution at nadir of about 500 m; and a range resolution of 120 m. The radar is designed to be applicable for retrieving rainfall rates from 0.1-60 mm/hr at the earth's surface, and for measuring linear polarization signatures and raindrop's fall velocity.

  12. CREST-Snow Field Experiment: analysis of snowpack properties using multi-frequency microwave remote sensing data

    NASA Astrophysics Data System (ADS)

    Lakhankar, T.; Muñoz, J.; Romanov, P.; Powell, A. M.; Krakauer, N.; Rossow, W.; Khanbilvardi, R.

    2012-07-01

    The CREST-Snow Analysis and Field Experiment (CREST-SAFE) was carried out during winter 2011 at the research site of the National Weather Service office, Caribou ME, USA. In this ground experiment, dual polarized microwave (37 and 89 GHz) observations are conducted along with detailed synchronous observations of snowpack properties. The objective of this long term field experiment is to improve our understanding of the effect of changing snow characteristics (grain size, density, temperature) under various meteorological conditions on the microwave emission of snow and hence to improve retrievals of snow cover properties from satellite observations in the microwave spectral range. In this paper, we presented the overview of field experiment and preliminary analysis of the microwave observations for the first year of experiment along with support observations of the snowpack properties obtained during the 2011 winter season. SNTHERM and HUT (Helsinki University of Technology) snow emission model were used to simulate snowpack properties and microwave brightness temperatures respectively. Simulated brightness temperatures were compared with observed brightness temperature from radiometer under different snow conditions. On the time series, large difference in the brightness temperature were observed for fresh compared to aged snow even under the same snow depth, suggesting a substantial impact of other parameters such as: snow grain size and density on microwave observations. A large diurnal variation in the 37 and 89 GHz brightness temperature with small depolarization factor was observed due to cold nights and warm days, which caused a cycling between wet snow and ice-over-snow states during the early spring. Scattering analysis of microwave brightness temperatures from radiometers were performed to distinguished different snow conditions developed through the winter season.

  13. Satellite passive microwave remote sensing for estimating diurnal variation of leaf water content, as a proxy of evapotranspiration, in the Dry Chaco Forest, Argentina

    NASA Astrophysics Data System (ADS)

    Barraza Bernadas, V.; Grings, F.; Ferrazzoli, P.; Carbajo, A.; Fernandez, R.; Karszenbaum, H.

    2012-12-01

    Evapotranspiration (ET) is a key component of water cycle, which is strongly linked with environmental condition and vegetation functioning. Since it is very difficult to robustly estimate it from remote sensing data at regional scale it is usually inferred from other proxies using water balance. This work describes a procedure to estimate ET in a dry forest by monitoring diurnal variation of leaf water content (LWC), using multitemporal passive microwave remote sensing observations. Hourly observations provide the opportunity to monitor repetitive diurnal variations of passive microwave observations, which can only be accounted by changes in LWC (which is itself related to water vapor that enters to the atmosphere from land surface). To this end, we calculated the vegetation frequency index (FI) as FI= 2*(TBKa-TBX)/ ((TBKa +TBX)), where TBKa and TBX indicate brightness temperatures at 37 and 10.6 GHz respectively. There is both theoretical and experimental evidence that link this index to microwave to LWC. The index was computed for vertical polarization, because it presents higher correlation with vegetation state. At diurnal temporal scale, changes in LWC are commonly very small. Nevertheless, it was previously shown that passive remote sensing data (FI computed using Ku and Ka bands) acquired at different hours can be used to estimate the seasonal changes in ET. In this work, we present a procedure based on the hourly changes of FI, which are interpreted as changes in LWC. In order to present a quantitative estimation, the discrete forest model described in (Ferrazzoli and Guerriero, 1996) has been used to simulate the variations of FI with LWC. To illustrate the procedure, AMSR-E and WINDSAT data from 2007-2009 at X and Ka bands were used, and up to four observations per day at four different local times (2.30 am, 7.00 am, 2.30 pm and 7.00 pm) were analyzed. The region addressed is the area of the Dry Chaco forest located in Bermejo River Basin in Argentina

  14. CREST-Snow Field Experiment: analysis of snowpack properties using multi-frequency microwave remote sensing data

    NASA Astrophysics Data System (ADS)

    Lakhankar, T. Y.; Muñoz, J.; Romanov, P.; Powell, A. M.; Krakauer, N. Y.; Rossow, W. B.; Khanbilvardi, R. M.

    2013-02-01

    The CREST-Snow Analysis and Field Experiment (CREST-SAFE) was carried out during January-March 2011 at the research site of the National Weather Service office, Caribou, ME, USA. In this experiment dual-polarized microwave (37 and 89 GHz) observations were accompanied by detailed synchronous observations of meteorology and snowpack physical properties. The objective of this long-term field experiment was to improve understanding of the effect of changing snow characteristics (grain size, density, temperature) under various meteorological conditions on the microwave emission of snow and hence to improve retrievals of snow cover properties from satellite observations. In this paper we present an overview of the field experiment and comparative preliminary analysis of the continuous microwave and snowpack observations and simulations. The observations revealed a large difference between the brightness temperature of fresh and aged snowpack even when the snow depth was the same. This is indicative of a substantial impact of evolution of snowpack properties such as snow grain size, density and wetness on microwave observations. In the early spring we frequently observed a large diurnal variation in the 37 and 89 GHz brightness temperature with small depolarization corresponding to daytime snowmelt and nighttime refreeze events. SNTHERM (SNow THERmal Model) and the HUT (Helsinki University of Technology) snow emission model were used to simulate snowpack properties and microwave brightness temperatures, respectively. Simulated snow depth and snowpack temperature using SNTHERM were compared to in situ observations. Similarly, simulated microwave brightness temperatures using the HUT model were compared with the observed brightness temperatures under different snow conditions to identify different states of the snowpack that developed during the winter season.

  15. Remote Sensing Observatory Validation of Surface Soil Moisture Using Advanced Microwave Scanning Radiometer E, Common Land Model, and Ground Based Data: Case Study in SMEX03 Little River Region, Georgia, U.S.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Optimal soil moisture estimation may be characterized by inter-comparisons among remotely sensed measurements, ground-based measurements, and land surface models. In this study, we compared soil moisture from Advanced Microwave Scanning Radiometer E (AMSR-E), ground-based measurements, and Soil-Vege...

  16. Active microwaves

    NASA Technical Reports Server (NTRS)

    Evans, D.; Vidal-Madjar, D.

    1994-01-01

    Research on the use of active microwaves in remote sensing, presented during plenary and poster sessions, is summarized. The main highlights are: calibration techniques are well understood; innovative modeling approaches have been developed which increase active microwave applications (segmentation prior to model inversion, use of ERS-1 scatterometer, simulations); polarization angle and frequency diversity improves characterization of ice sheets, vegetation, and determination of soil moisture (X band sensor study); SAR (Synthetic Aperture Radar) interferometry potential is emerging; use of multiple sensors/extended spectral signatures is important (increase emphasis).

  17. Airborne gamma radiation measurements of soil moisture during FIFE: Activities and results

    NASA Technical Reports Server (NTRS)

    Peck, Eugene L.

    1992-01-01

    Soil moisture measurements were obtained during the summer of 1987 and 1989 near Manhattan, Kansas, using the National Weather Service (NWS) airborne gamma radiation system. A network of 24 flight lines were established over the research area. Airborne surveys were flown daily during two intensive field campaigns. The data collected was sufficient to modify the NWS standard operational method for estimating soil moisture for the Field Experiment (FIFE) flight lines. The average root mean square error of the soil moisture estimates for shorter FIFE flight lines was found to be 2.5 percent, compared with a reported value of 3.9 percent for NWS flight lines. Techniques were developed to compute soil moisture estimates for portions of the flight lines. Results of comparisons of the airborne gamma radiation soil moisture estimates with those obtained using the NASA Pushbroom Microwave Radiation (PBMR) system and hydrological model are presented. The airborne soil moisture measurements, and real averages computed using all remotely sensed and ground data, have been in support of the research of the many FIFE investigators whose overall goal was the upscale integration of models and the application of satellite remote sensing.

  18. Application of NASA's modern era retrospective-analysis in Global Wetlands Mappings Derived from Coarse-Resolution Satellite Microwave Remote Sensing

    NASA Astrophysics Data System (ADS)

    Schröder, R.; McDonald, K. C.; Podest, E.; Jones, L. A.; Kimball, J. S.; Pinto, N.; Zimmermann, R.; Küppers, M.

    2011-12-01

    The sensitivity of Earth's wetlands to observed shifts in global precipitation and temperature patterns and their ability to produce large quantities of methane gas are key global change questions. Global methane emissions are typically estimated via process-based models calibrated to individual wetland sites. Regardless of the complexity of these process-based models, accurate geographical distribution and seasonality of recent global wetland extent are typically not accounted for in such an approach, which may explain the large variations in estimated global methane emissions as well as the significant interannual variations in the observed atmospheric growth rate of methane. Spatially comprehensive ground observation networks of large-scale inundation patterns are very sparse because they require large fiscal, technological and human resources. Satellite remote sensing of global inundation dynamics thus can support the ability for a complete synoptic view of past and current inundation dynamics over large areas that otherwise could not be assessed. Coarse-resolution (~25km) satellite data from passive and active microwave instruments are well suited for the global observation of large-scale inundation patterns because they are primarily sensitive to the associated dielectric properties of the landscape and cover large areas within a relatively short amount of time (up to daily repeat in high latitudes). This study summarizes a new remote sensing technique for quantifying global daily surface water fractions based on combined passive-active microwave remote sensing data sets from the AMSR-E and QuikSCAT instruments over a 7 year period (July 2002 - July 2009). We apply these data with ancillary land cover maps from MODIS to: 1) define the potential global domain of surface water impacted land; 2) establish land cover driven predictive equations for implementing a dynamic mixture model adjusted to total column water vapor obtained from NASA's modern era

  19. Comparisons of remotely sensed and model-simulated soil moisture over a heterogeneous watershed

    SciTech Connect

    Lin, D.S.; Wood, E.F. . Dept. of Civil Engineering and Operations Research); Troch, P.A. . Lab. of Hydrology and Water Management); Mancini, M. ); Jackson, T.J. . ARS Hydrology Lab.)

    1994-05-01

    Soil moisture estimates from a distributed hydrologic model and two microwave airborne sensors (Push Broom Microwave Radiometer and Synthetic Aperture Radar) are compared with ground measurements on two different scales, using data collected during afield experiment over a 7.4-km[sup 2] heterogeneous watershed located in central Pennsylvania. It is found that both microwave sensors and the hydrologic model successfully reflect the temporal variation of soil moisture. Watershed-averaged soil moistures estimated by the microwave sensors are in good agreement with ground measurements. The hydrologic model initialized by streamflow records yields estimates that are wetter than observations. The preliminary test of utilizing remotely sensed information as a feedback to correct the initial state of the hydrologic model shows promising results.

  20. Influence of spatial variability of hydraulic characteristics of soils on surface parameters obtained from remote sensing data in infrared and microwaves

    NASA Technical Reports Server (NTRS)

    Brunet, Y.; Vauclin, M.

    1985-01-01

    The correct interpretation of thermal and hydraulic soil parameters infrared from remotely sensed data (thermal infrared, microwaves) implies a good understanding of the causes of their temporal and spatial variability. Given this necessity, the sensitivity of the surface variables (temperature, moisture) to the spatial variability of hydraulic soil properties is tested with a numerical model of heat and mass transfer between bare soil and atmosphere. The spatial variability of hydraulic soil properties is taken into account in terms of the scaling factor. For a given soil, the knowledge of its frequency distribution allows a stochastic use of the model. The results are treated statistically, and the part of the variability of soil surface parameters due to that of soil hydraulic properties is evaluated quantitatively.

  1. An Airborne Conical Scanning Millimeter-Wave Imaging Radiometer (CoSMIR)

    NASA Technical Reports Server (NTRS)

    Piepmeier, J.; Racette, P.; Wang, J.; Crites, A.; Doiron, T.; Engler, C.; Lecha, J.; Powers, M.; Simon, E.; Triesky, M.; Krebs, Carolyn A. (Technical Monitor)

    2001-01-01

    An airborne Conical Scanning Millimeter-wave Imaging Radiometer (CoSMIR) for high-altitude observations from the NASA Research Aircraft (ER-2) is discussed. The primary application of the CoSMIR is water vapor profile remote sensing. Four radiometers operating at 50 (three channels), 92, 150, and 183 (three channels) GHz provide spectral coverage identical to nine of the Special Sensor Microwave Imager/Sounder (SSMIS) high-frequency channels. Constant polarization-basis conical and cross-track scanning capabilities are achieved using an elevation-under-azimuth two-axis gimbals.

  2. Spaceborne Microwave Remote Sensing of Seasonal Freeze-Thaw Processes in the Terrestrial High Latitudes: Relationships with Land-Atmosphere CO2 exchange

    NASA Technical Reports Server (NTRS)

    McDonald, Kyle C.; Kimball, John S.; Zhao, Maosheng; Njoku, Eni; Zimmermann, Reiner; Running, Steven W.

    2004-01-01

    Landscape transitions between seasonally frozen and thawed conditions occur each year over roughly 50 million square kilometers of Earth's Northern Hemisphere. These relatively abrupt transitions represent the closest analog to a biospheric and hydrologic on/off switch existing in nature, affecting surface meteorological conditions, ecological trace gas dynamics, energy exchange and hydrologic activity profoundly. We utilize time series satellite-borne microwave remote sensing measurements from the Special Sensor Microwave Imager (SSM/I) to examine spatial and temporal variability in seasonal freeze/thaw cycles for the pan-Arctic basin and Alaska. Regional measurements of spring thaw timing are derived using daily brightness temperature measurements from the 19 GHz, horizontally polarized channel, separately for overpasses with 6 AM and 6 PM equatorial crossing times. Spatial and temporal patterns in regional freeze/thaw dynamics show distinct differences between North America and Eurasia, and boreal forest and Arctic tundra biomes. Annual anomalies in the timing of thawing in spring also correspond closely to seasonal atmospheric CO2 concentration anomalies derived from NOAA CMDL arctic and subarctic monitoring stations. Classification differences between AM and PM overpass data average approximately 5 days for the region, though both appear to be effective surrogates for monitoring annual growing seasons at high latitudes.

  3. Spaceborne microwave remote sensing of seasonal freeze-thaw processes in theterrestrial high l atitudes : relationships with land-atmosphere CO2 exchange

    NASA Technical Reports Server (NTRS)

    McDonald, Kyle C.; Kimball, John S.; Zhao, Maosheng; Njoku, Eni; Zimmermann, Reiner; Running, Steven W.

    2004-01-01

    Landscape transitions between seasonally frozen and thawed conditions occur each year over roughly 50 million square kilometers of Earth's Northern Hemisphere. These relatively abrupt transitions represent the closest analog to a biospheric and hydrologic on/off switch existing in nature, affecting surface meteorological conditions, ecological trace gas dynamics, energy exchange and hydrologic activity profoundly. We utilize time series satellite-borne microwave remote sensing measurements from the Special Sensor Microwave Imager (SSM/I) to examine spatial and temporal variability in seasonal freeze/thaw cycles for the pan-Arctic basin and Alaska. Regional measurements of spring thaw timing are derived using daily brightness temperature measurements from the 19 GHz, horizontally polarized channel, separately for overpasses with 6 AM and 6 PM equatorial crossing times. Spatial and temporal patterns in regional freeze/thaw dynamics show distinct differences between North America and Eurasia, and boreal forest and Arctic tundra biomes. Annual anomalies in the timing of thawing in spring also correspond closely to seasonal atmospheric CO2 concentration anomalies derived from NOAA CMDL arctic and subarctic monitoring stations. Classification differences between AM and PM overpass data average approximately 5 days for the region, though both appear to be effective surrogates for monitoring annual growing seasons at high latitudes.

  4. Microwave emissions from snow

    NASA Technical Reports Server (NTRS)

    Chang, A. T. C.

    1984-01-01

    The radiation emitted from dry and wet snowpack in the microwave region (1 to 100 GHz) is discussed and related to ground observations. Results from theoretical model calculations match the brightness temperatures obtained by truck mounted, airborne and spaceborne microwave sensor systems. Snow wetness and internal layer structure complicate the snow parameter retrieval algorithm. Further understanding of electromagnetic interaction with snowpack may eventually provide a technique to probe the internal snow properties

  5. Retrieval techniques and information content analysis to improve remote sensing of atmospheric water vapor, liquid water and temperature from ground-based microwave radiometer measurements

    NASA Astrophysics Data System (ADS)

    Sahoo, Swaroop

    Observation of profiles of temperature, humidity and winds with sufficient accuracy and fine vertical and temporal resolution are needed to improve mesoscale weather prediction, track conditions in the lower to mid-troposphere, predict winds for renewable energy, inform the public of severe weather and improve transportation safety. In comparing these thermodynamic variables, the absolute atmospheric temperature varies only by 15%; in contrast, total water vapor may change by up to 50% over several hours. In addition, numerical weather prediction (NWP) models are initialized using water vapor profile information, so improvements in their accuracy and resolution tend to improve the accuracy of NWP. Current water vapor profile observation systems are expensive and have insufficient spatial coverage to observe humidity in the lower to mid-troposphere. To address this important scientific need, the principal objective of this dissertation is to improve the accuracy, vertical resolution and revisit time of tropospheric water vapor profiles retrieved from microwave and millimeter-wave brightness temperature measurements. This dissertation advances the state of knowledge of retrieval of atmospheric water vapor from microwave brightness temperature measurements. It focuses on optimizing two information sources of interest for water vapor profile retrieval, i.e. independent measurements and background data set size. From a theoretical perspective, it determines sets of frequencies in the ranges of 20-23, 85-90 and 165-200 GHz that are optimal for water vapor retrieval from each of ground-based and airborne radiometers. The maximum number of degrees of freedom for the selected frequencies for ground-based radiometers is 5-6, while the optimum vertical resolution is 0.5 to 1.5 km. On the other hand, the maximum number of degrees of freedom for airborne radiometers is 8-9, while the optimum vertical resolution is 0.2 to 0.5 km. From an experimental perspective, brightness

  6. Diurnal variations of stratospheric ozone measured by ground-based microwave remote sensing at the Mauna Loa NDACC site: measurement validation and GEOSCCM model comparison

    NASA Astrophysics Data System (ADS)

    Parrish, A.; Boyd, I. S.; Nedoluha, G. E.; Bhartia, P. K.; Frith, S. M.; Kramarova, N. A.; Connor, B. J.; Bodeker, G. E.; Froidevaux, L.; Shiotani, M.; Sakazaki, T.

    2014-07-01

    There is presently renewed interest in diurnal variations of stratospheric and mesospheric ozone for the purpose of supporting homogenization of records of various ozone measurements that are limited by the technique employed to being made at certain times of day. We have made such measurements for 19 years using a passive microwave remote sensing technique at the Mauna Loa Observatory (MLO) in Hawaii, which is a primary station in the Network for Detection of Atmospheric Composition Change (NDACC). We have recently reprocessed these data with hourly time resolution to study diurnal variations. We inspected differences between pairs of the ozone spectra (e.g., day and night) from which the ozone profiles are derived to determine the extent to which they may be contaminated by diurnally varying systematic instrumental or measurement effects. These are small, and we have reduced them further by selecting data that meet certain criteria that we established. We have calculated differences between profiles measured at different times: morning-night, afternoon-night, and morning-afternoon and have intercompared these with like profiles derived from the Aura Microwave Limb Sounder (Aura-MLS), the Upper Atmosphere Research Satellite Microwave Limb Sounder (UARS-MLS), the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES), and Solar Backscatter Ultraviolet version 2 (SBUV/2) measurements. Differences between averages of coincident profiles are typically < 1.5% of typical nighttime values over most of the covered altitude range with some exceptions. We calculated averages of ozone values for each hour from the Mauna Loa microwave data, and normalized these to the average for the first hour after midnight for comparison with corresponding values calculated with the Goddard Earth Observing System Chemistry Climate Model (GEOSCCM). We found that the measurements and model output mostly agree to better than 1.5% of the midnight value, with one noteworthy exception

  7. Ground-Based Passive Microwave Remote Sensing Observations of Soil Moisture at S and L Band with Insight into Measurement Accuracy

    NASA Technical Reports Server (NTRS)

    Laymon, Charles A.; Crosson, William L.; Jackson, Thomas J.; Manu, Andrew; Tsegaye, Teferi D.; Soman, V.; Arnold, James E. (Technical Monitor)

    2001-01-01

    Accurate estimates of spatially heterogeneous algorithm variables and parameters are required in determining the spatial distribution of soil moisture using radiometer data from aircraft and satellites. A ground-based experiment in passive microwave remote sensing of soil moisture was conducted in Huntsville, Alabama from July 1-14, 1996 to study retrieval algorithms and their sensitivity to variable and parameter specification. With high temporal frequency observations at S and L band, we were able to observe large scale moisture changes following irrigation and rainfall events, as well as diurnal behavior of surface moisture among three plots, one bare, one covered with short grass and another covered with alfalfa. The L band emitting depth was determined to be on the order of 0-3 or 0-5 cm below 0.30 cubic centimeter/cubic centimeter with an indication of a shallower emitting depth at higher moisture values. Surface moisture behavior was less apparent on the vegetated plots than it was on the bare plot because there was less moisture gradient and because of difficulty in determining vegetation water content and estimating the vegetation b parameter. Discrepancies between remotely sensed and gravimetric, soil moisture estimates on the vegetated plots point to an incomplete understanding of the requirements needed to correct for the effects of vegetation attenuation. Quantifying the uncertainty in moisture estimates is vital if applications are to utilize remotely-sensed soil moisture data. Computations based only on the real part of the complex dielectric constant and/or an alternative dielectric mixing model contribute a relatively insignificant amount of uncertainty to estimates of soil moisture. Rather, the retrieval algorithm is much more sensitive to soil properties, surface roughness and biomass.

  8. Wearable microwave radiometers for remote fire detection: System-on-Chip (SoC) design and proof of the concept.

    PubMed

    Tasselli, G; Alimenti, F; Fonte, A; Zito, D; Roselli, L; De Rossi, D; Lanatà, A; Neri, B; Tognetti, A

    2008-01-01

    The paper reports the present status of the project aimed at the realization of a wearable low-cost low-power System-on-Chip (SoC) 13-GHz passive microwave radiometer in CMOS 90 nm technology. This sensor has been thought to be inserted into the firemen jacket in order to help them in the detection of a hidden fire behind a door or a wall, especially where the IR technology fail. With respect of the prior art, the SoC is further developed and a proof of the concept is provided by means of a discrete-component prototype.

  9. Wearable microwave radiometers for remote fire detection: System-on-Chip (SoC) design and proof of the concept.

    PubMed

    Tasselli, G; Alimenti, F; Fonte, A; Zito, D; Roselli, L; De Rossi, D; Lanatà, A; Neri, B; Tognetti, A

    2008-01-01

    The paper reports the present status of the project aimed at the realization of a wearable low-cost low-power System-on-Chip (SoC) 13-GHz passive microwave radiometer in CMOS 90 nm technology. This sensor has been thought to be inserted into the firemen jacket in order to help them in the detection of a hidden fire behind a door or a wall, especially where the IR technology fail. With respect of the prior art, the SoC is further developed and a proof of the concept is provided by means of a discrete-component prototype. PMID:19162822

  10. Ocean experiments and remotely sensed images of chemically dispersed oil spills

    NASA Technical Reports Server (NTRS)

    Croswell, W. F.; Fedors, J. C.; Hoge, F. E.; Swift, R. N.; Johnson, J. C.

    1983-01-01

    A series of experiments was performed at sea where the effectiveness of dispersants applied from a helicopter was tested on fresh and weathered crude oils released from a surface research vessel. In conjunction with these experiments, remote sensing measurements using an array of airborne optical and microwave sensors were performed in order to aid in the interpretation of the dispersant effectiveness and to obtain quantitative images of oil on the sea under controlled conditions. Surface oil thickness and volume are inferred from airborne measurements using a dual-channel microwave imaging radiometer, aerial color photography, and an airborne oceanographic lidar. The remotely sensed measurements are compared with point sampled data obtained using a research vessel. The mass balance computations of surface versus subsurface oil volume using remotely sensed and point sampled data are consistent with each other and with the volumes of oil released. Data collected by the several techniques concur in indicating that, for the oils used and under the sea conditions encountered, the dispersant and application method are primarily useful when applied to fresh oil.

  11. Characterization of Inundated Wetlands with Microwave Remote Sensing: Cross-Product Comparison for Uncertainty Assessment in Tropical Wetlands

    NASA Astrophysics Data System (ADS)

    McDonald, K. C.; Jensen, K.; Alvarez, J.; Azarderakhsh, M.; Schroeder, R.; Podest, E.; Chapman, B. D.; Zimmermann, R.

    2015-12-01

    We have been assembling a global-scale Earth System Data Record (ESDR) of natural Inundated Wetlands to facilitate investigations on their role in climate, biogeochemistry, hydrology, and biodiversity. The ESDR comprises (1) Fine-resolution (100 meter) maps, delineating wetland extent, vegetation type, and seasonal inundation dynamics for regional to continental-scale areas, and (2) global coarse-resolution (~25 km), multi-temporal mappings of inundated area fraction (Fw) across multiple years. During March 2013, the NASA/JPL L-band polarimetric airborne imaging radar, UAVSAR, conducted airborne studies over regions of South America including portions of the western Amazon basin. We collected UAVSAR datasets over regions of the Amazon basin during that time to support systematic analyses of error sources related to the Inundated Wetlands ESDR. UAVSAR datasets were collected over Pacaya Samiria, Peru, Madre de Dios, Peru, and the Napo River in Ecuador. We derive landcover classifications from the UAVSAR datasets emphasizing wetlands regions, identifying regions of open water and inundated vegetation. We compare the UAVSAR-based datasets with those comprising the ESDR to assess uncertainty associated with the high resolution and the coarse resolution ESDR components. Our goal is to create an enhanced ESDR of inundated wetlands with statistically robust uncertainty estimates. The ESDR documentation will include a detailed breakdown of error sources and associated uncertainties within the data record. This work was carried out in part within the framework of the ALOS Kyoto & Carbon Initiative. PALSAR data were provided by JAXA/EORC and the Alaska Satellite Facility. Portions of this work were conducted at the Jet Propulsion Laboratory, California Institute of Technology under contract to the National Aeronautics and Space Administration.

  12. Using high-resolution soil moisture modelling to assess the uncertainty of microwave remotely sensed soil moisture products at the correct spatial and temporal support

    NASA Astrophysics Data System (ADS)

    Wanders, N.; Karssenberg, D.; Bierkens, M. F. P.; Van Dam, J. C.; De Jong, S. M.

    2012-04-01

    Soil moisture is a key variable in the hydrological cycle and important in hydrological modelling. When assimilating soil moisture into flood forecasting models, the improvement of forecasting skills depends on the ability to accurately estimate the spatial and temporal patterns of soil moisture content throughout the river basin. Space-borne remote sensing may provide this information with a high temporal and spatial resolution and with a global coverage. Currently three microwave soil moisture products are available: AMSR-E, ASCAT and SMOS. The quality of these satellite-based products is often assessed by comparing them with in-situ observations of soil moisture. This comparison is however hampered by the difference in spatial and temporal support (i.e., resolution, scale), because the spatial resolution of microwave satellites is rather low compared to in-situ field measurements. Thus, the aim of this study is to derive a method to assess the uncertainty of microwave satellite soil moisture products at the correct spatial support. To overcome the difference in support size between in-situ soil moisture observations and remote sensed soil moisture, we used a stochastic, distributed unsaturated zone model (SWAP, van Dam (2000)) that is upscaled to the support of different satellite products. A detailed assessment of the SWAP model uncertainty is included to ensure that the uncertainty in satellite soil moisture is not overestimated due to an underestimation of the model uncertainty. We simulated unsaturated water flow up to a depth of 1.5m with a vertical resolution of 1 to 10 cm and on a horizontal grid of 1 km2 for the period Jan 2010 - Jun 2011. The SWAP model was first calibrated and validated on in-situ data of the REMEDHUS soil moisture network (Spain). Next, to evaluate the satellite products, the model was run for areas in the proximity of 79 meteorological stations in Spain, where model results were aggregated to the correct support of the satellite

  13. Diurnal variations of stratospheric ozone measured by ground-based microwave remote sensing at the Mauna Loa NDACC site: measurement validation and GEOSCCM model comparison

    NASA Astrophysics Data System (ADS)

    Parrish, A.; Boyd, I. S.; Nedoluha, G. E.; Bhartia, P. K.; Frith, S. M.; Kramarova, N. A.; Connor, B. J.; Bodeker, G. E.; Froidevaux, L.; Shiotani, M.; Sakazaki, T.

    2013-12-01

    There is presently renewed interest in diurnal variations of stratospheric and mesospheric ozone for the purpose of supporting homogenization of records of various ozone measurements that are limited by the technique employed to being made at certain times of day. We have made such measurements for 18 yr using a passive microwave remote sensing technique at the Mauna Loa Observatory in Hawaii, which is a primary station in the Network for Detection of Atmospheric Composition Change (NDACC). We have recently reprocessed these data with hourly time resolution to study diurnal variations. We inspected differences between pairs of the ozone spectra (e.g. day and night) from which the ozone profiles are derived to determine the extent to which they may be contaminated by diurnally varying systematic instrumental or measurement effects. These are small, and we have reduced them further by selecting data that meet certain criteria that we established. We have calculated differences between profiles measured at different times: morning-night, afternoon-night, and morning-afternoon and have intercompared these with like profiles derived from Aura-MLS, UARS-MLS, SMILES, and SBUV/2 measurements. Differences between averages of coincident profiles are typically <1.5% of typical nightime values over most of the covered altitude range with some exceptions. We calculated averages of ozone values for each hour from the Mauna Loa microwave data, and normalized these to the average for the first hour after midnight for comparison with corresponding values calculated with the Goddard Earth Observing System Chemistry Climate Model (GEOSCCM). We found that the measurements and model output mostly agree to better than 1.5% of the midnight value, with one noteworthy exception: the measured morning-night values are significantly (2-3%) higher than the modeled ones from 3.2 to 1.8 hPa (~39-43 km), and there is evidence that the measured values are increasing compared to the modeled values

  14. Investigation of airborne lidar for avoidance of windshear hazards

    NASA Technical Reports Server (NTRS)

    Targ, Russell; Bowles, Roland L.

    1988-01-01

    The present generalized windshear hazard index is formulated in terms of wind conditions at the given aircraft position and of remotely-sensed information obtained along the extended flight path. Overall system functional requirements are addressed by comparing microwave Doppler radar, Doppler lidar, and IR radiometry candidate techniques, giving attention to airborne CO2 and Ho:YAG lidar windshear-detection systems; these furnish pilots with data on the line-of-sight component of windshear threats over as much as 1-3 km, for a warning time of 15-45 sec. While the technology for a 10.6-micron, CO2 laser-based lidar is available, additional development is required for 2-micron, Ho:YAG laser-based systems.

  15. A Melting Layer Model for Passive/Active Microwave Remote Sensing Applications. Part 1; Model Formulation and Comparison with Observations

    NASA Technical Reports Server (NTRS)

    Olson, William S.; Bauer, Peter; Viltard, Nicolas F.; Johnson, Daniel E.; Tao, Wei-Kuo

    2000-01-01

    In this study, a 1-D steady-state microphysical model which describes the vertical distribution of melting precipitation particles is developed. The model is driven by the ice-phase precipitation distributions just above the freezing level at applicable gridpoints of "parent" 3-D cloud-resolving model (CRM) simulations. It extends these simulations by providing the number density and meltwater fraction of each particle in finely separated size categories through the melting layer. The depth of the modeled melting layer is primarily determined by the initial material density of the ice-phase precipitation. The radiative properties of melting precipitation at microwave frequencies are calculated based upon different methods for describing the dielectric properties of mixed phase particles. Particle absorption and scattering efficiencies at the Tropical Rainfall Measuring Mission Microwave Imager frequencies (10.65 to 85.5 GHz) are enhanced greatly for relatively small (approx. 0.1) meltwater fractions. The relatively large number of partially-melted particles just below the freezing level in stratiform regions leads to significant microwave absorption, well-exceeding the absorption by rain at the base of the melting layer. Calculated precipitation backscatter efficiencies at the Precipitation Radar frequency (13.8 GHz) increase in proportion to the particle meltwater fraction, leading to a "bright-band" of enhanced radar reflectivities in agreement with previous studies. The radiative properties of the melting layer are determined by the choice of dielectric models and the initial water contents and material densities of the "seeding" ice-phase precipitation particles. Simulated melting layer profiles based upon snow described by the Fabry-Szyrmer core-shell dielectric model and graupel described by the Maxwell-Garnett water matrix dielectric model lead to reasonable agreement with radar-derived melting layer optical depth distributions. Moreover, control profiles

  16. MAPIR: An Airborne Polarmetric Imaging Radiometer in Support of Hydrologic Satellite Observations

    NASA Technical Reports Server (NTRS)

    Laymon, C.; Al-Hamdan, M.; Crosson, W.; Limaye, A.; McCracken, J.; Meyer, P.; Richeson, J.; Sims, W.; Srinivasan, K.; Varnevas, K.

    2010-01-01

    In this age of dwindling water resources and increasing demands, accurate estimation of water balance components at every scale is more critical to end users than ever before. Several near-term Earth science satellite missions are aimed at global hydrologic observations. The Marshall Airborne Polarimetric Imaging Radiometer (MAPIR) is a dual beam, dual angle polarimetric, scanning L band passive microwave radiometer system developed by the Observing Microwave Emissions for Geophysical Applications (OMEGA) team at MSFC to support algorithm development and validation efforts in support of these missions. MAPIR observes naturally-emitted radiation from the ground primarily for remote sensing of land surface brightness temperature from which we can retrieve soil moisture and possibly surface or water temperature and ocean salinity. MAPIR has achieved Technical Readiness Level 6 with flight heritage on two very different aircraft, the NASA P-3B, and a Piper Navajo.

  17. Mapping UK snow accumulation using satellite passive microwave and visible-infrared remote sensing observations: two case studies from 2009 and 2010

    NASA Astrophysics Data System (ADS)

    Kelly, Richard

    2010-05-01

    In February 2009, an unusually significant snow storm deposited considerable amounts of snow in the UK for the first time in several years. A more persistent event deposited larger amounts of snow between December 2009 and January 2010; during this time snow cover duration exceeded a month in some locations and on 7 January, England Scotland and Wales were almost completely covered in snow as observed by NASA's Moderate Resolution Imaging Spectroradiometer (MODIS). Such widespread snow cover has not been observed since 1963 and 1979. Information about snow quantity and distribution in the UK is sparse and while some official observations are made, most observations are made through community-based observers or via more esoteric online social networks. Furthermore, daily snow accumulation maps are not easily obtainable for the UK. Coupled with unusually cold temperatures which began in mid December, these case studies provide an excellent opportunity to re-evaluate the role of satellite passive microwave observations for estimating snow water equivalent in the UK. Satellite remote sensing observations were obtained for the two snow event periods. MODIS observations are used to determine the location of the snow when cloud does not obscure the field of view. Passive microwave observations from the Advanced Microwave Scanning Radiometer - EOS (AMSR-E) are used to estimate SWE. In the first instance, AMSR-E estimates from the standard NASA algorithm are tested. On account of the documented radio frequency interference at 10 GHz the estimates are deemed unsuitable. A re-configured algorithm is developed at the native sampling resolution (10 km in along and across track) projected to a UTM grid. The re-configured approach to estimate SWE uses 18, 23 36 and 89GHz channels (vertical and horizontal polarization) and uses a frequency ratio approach, rather than difference, to minimize the physical temperature effect on brightness temperatures at 18, 36 and 89 GHz. It also

  18. Land cover/use classification of Cairns, Queensland, Australia: A remote sensing study involving the conjunctive use of the airborne imaging spectrometer, the large format camera and the thematic mapper simulator

    NASA Technical Reports Server (NTRS)

    Heric, Matthew; Cox, William; Gordon, Daniel K.

    1987-01-01

    In an attempt to improve the land cover/use classification accuracy obtainable from remotely sensed multispectral imagery, Airborne Imaging Spectrometer-1 (AIS-1) images were analyzed in conjunction with Thematic Mapper Simulator (NS001) Large Format Camera color infrared photography and black and white aerial photography. Specific portions of the combined data set were registered and used for classification. Following this procedure, the resulting derived data was tested using an overall accuracy assessment method. Precise photogrammetric 2D-3D-2D geometric modeling techniques is not the basis for this study. Instead, the discussion exposes resultant spectral findings from the image-to-image registrations. Problems associated with the AIS-1 TMS integration are considered, and useful applications of the imagery combination are presented. More advanced methodologies for imagery integration are needed if multisystem data sets are to be utilized fully. Nevertheless, research, described herein, provides a formulation for future Earth Observation Station related multisensor studies.

  19. The Western Airborne Contaminant Assessment Project (WACAP): An interdisciplinary evaluation of the impacts of airborne contaminants in Western U.S. National Parks

    EPA Science Inventory

    The Western Airborne Contaminants Assessment Project (WACAP) was initiated in 2002 by the National Park Service to determine if airborne contaminants were having an impact on remote western ecosystems. Multiple sample media (snow, water, sediment, fish and terrestrial vegetation...

  20. Airborne Transparencies.

    ERIC Educational Resources Information Center

    Horne, Lois Thommason

    1984-01-01

    Starting from a science project on flight, art students discussed and investigated various means of moving in space. Then they made acetate illustrations which could be used as transparencies. The projection phenomenon made the illustrations look airborne. (CS)

  1. Development of Wide-Band Airborne Microwave and Millimeter-Wave Radiometers to Provide High-Resolution Wet-Tropospheric Path Delay Measurements for Coastal and Inland Water Altimetry

    NASA Astrophysics Data System (ADS)

    Reising, S. C.; Kangaslahti, P.; Brown, S. T.; Tanner, A. B.; Padmanabhan, S.; Parashare, C.; Bosch-Lluis, X.; Nelson, S. P.; Johnson, T. P.; Hadel, V. D.; Dawson, D. E.; Montes, O.; Gaier, T. C.; Khayatian, B.; Gilliam, K. L.; Razavi, B.

    2012-12-01

    across the swath will affect altimeter accuracy. To reduce the risks associated with wet-tropospheric path delay correction over coastal areas and fresh water bodies, we will develop, build and flight test an airborne radiometer with the Advanced Microwave Radiometer (18.7, 23.8 and 34.0 GHz) channels, millimeter-wave (90, 130 and 166 GHz) window channels, and millimeter-wave sounders near 118 and 183 GHz to validate over-land retrievals of wet-path delay. In addition, a high spectral resolution ASIC is under development to substantially reduce the mass and power of millimeter-wave spectrometers. The millimeter-wave radiometer channels will have substantially improved spatial resolution and the potential for multiple fields of view across the radar's swath. This instrument development and airborne flight demonstration will (1) assess wet-tropospheric path delay variability on 10-km and smaller spatial scales, (2) demonstrate millimeter-wave radiometry using both window and sounding channels to improve both coastal and over-land retrievals of wet-tropospheric path delay, and (3) provide an instrument for calibration and validation in support of the SWOT mission.

  2. Integrating passive microwave remotely sensed imagery and gridded atmospheric data: A study of North American Prairie snow cover

    NASA Astrophysics Data System (ADS)

    Derksen, Christopher Peter

    Terrestrial snow cover is an important climatological variable because of its influence on the surface radiative balance, and a significant hydrological variable as it acts as the frozen storage term in the water balance. Satellite passive-microwave imagery has been used as a source of snow cover information because of all-weather imaging capabilities, rapid scene revisit time, and the ability to derive quantitative estimates of snow water equivalent (SWE). In this study, ten winter seasons (December, January, February 1988/89 to 1997/98) of five day averaged (pentad) passive-microwave derived SWE imagery are utilized to examine the seasonal snow cover characteristics of a ground-validated North American Prairie study area. Four dominant patterns are identified within the DeltaSWE time series. The positive (negative) phase of PC1 captures a pattern of widespread SWE ablation (accumulation) in the south with accumulation (ablation) to the north. The positive (negative) phase of PC2 characterizes a meridional accumulation (ablation) zone oriented from the northwest to southeast of the study area. The positive (negative) phase of PC3 indicates a regional melt event (accumulation event) in the lee of the Rocky Mountains. Finally, the positive (negative) phase of PC4 characterizes increasing (decreasing) SWE in the vicinity of the Red River Valley. National Center for Environmental Prediction (NCEP) gridded atmospheric data (500 mb geopotential height; 700 mb temperature) and model produced isentropic potential vorticity (IPV) fields are investigated in conjunction with the first four DeltaSWE principal components to identify whether consistency exists in the atmospheric patterns associated, at no time lag, with these dominant DeltaSWE modes. When a deep eastern Arctic low with an associated trough extends over the continental interior of North America, snow accumulation is the expected response (as characterized DeltaSWE PC1 positive, PC2 positive, and PC4 positive

  3. Spatiotemporal analysis of soil moisture in using active and passive remotely sensed data and ground observations

    NASA Astrophysics Data System (ADS)

    Li, H.; Fang, B.; Lakshmi, V.

    2015-12-01

    Abstract: Soil moisture plays a vital role in ecosystem, biological processes, climate, weather and agriculture. The Soil Moisture Active Passive (SMAP) improves data by combining the advantages and avoiding the limitation of passive microwave remote sensing (low resolution), and active microwave (challenge of soil moisture retrieval). This study will advance the knowledge of the application of soil moisture by using the Soil Moisture Active Passive Validation Experiment 2012 (SMAPVEX12) data as well as data collected at Walnut Gulch Arizona in August 2015 during SMAPVEX15. Specifically, we will analyze the 5m radar data from Unmanned Airborne Vehicle Synthetic Aperture Radar (UAVSAR) to study spatial variability within the PALS radiometer pixel. SMAPVEX12/15 and SMAP data will also be analyzed to evaluate disaggregation algorithms. The analytical findings will provide valuable information for policy-makers to initiate and adjust protocols and regulations for protecting land resources and improving environmental conditions. Keywords: soil moisture, Remote Sensing (RS), spatial statistic

  4. Remote Sensing of Aerosol Backscatter and Earth Surface Targets By Use of An Airborne Focused Continuous Wave CO2 Doppler Lidar Over Western North America

    NASA Technical Reports Server (NTRS)

    Jarzembski, Maurice A.; Srivastava, Vandana; Goodman, H. Michael (Technical Monitor)

    2000-01-01

    Airborne lidar systems are used to determine wind velocity and to measure aerosol or cloud backscatter variability. Atmospheric aerosols, being affected by local and regional sources, show tremendous variability. Continuous wave (cw) lidar can obtain detailed aerosol loading with unprecedented high resolution (3 sec) and sensitivity (1 mg/cubic meter) as was done during the 1995 NASA Multi-center Airborne Coherent Atmospheric Wind Sensor (MACAWS) mission over western North America and the Pacific Ocean. Backscatter variability was measured at a 9.1 micron wavelength cw focused CO2 Doppler lidar for approximately 52 flight hours, covering an equivalent horizontal distance of approximately 30,000 km in the troposphere. Some quasi-vertical backscatter profiles were also obtained during various ascents and descents at altitudes that ranged from approximately 0.1 to 12 km. Similarities and differences for aerosol loading over land and ocean were observed. Mid-tropospheric aerosol backscatter background mode was approximately 6 x 10(exp -11)/ms/r, consistent with previous lidar datasets. While these atmospheric measurements were made, the lidar also retrieved a distinct backscatter signal from the Earth's surface from the unfocused part of the focused cw lidar beam during aircraft rolls. Atmospheric backscatter can be highly variable both spatially and temporally, whereas, Earth-surface backscatter is relatively much less variant and can be quite predictable. Therefore, routine atmospheric backscatter measurements by an airborne lidar also give Earth surface backscatter which can allow for investigating the Earth terrain. In the case where the Earth's surface backscatter is coming from a well-known and fairly uniform region, then it can potentially offer lidar calibration opportunities during flight. These Earth surface measurements over varying Californian terrain during the mission were compared with laboratory backscatter measurements using the same lidar of various

  5. Case Studies for UV, O2-A Band and Polarimetric Airborne Remote Sensing Observations of Coastal Waters: Implications for Atmospheric Correction.

    NASA Astrophysics Data System (ADS)

    Chowdhary, J.; van Diedenhoven, B.; Knobelspiesse, K. D.; Cairns, B.; Wasilewski, A. P.; Mccubbin, I. B.

    2014-12-01

    A major challenge for spaceborne observations of ocean color is to correct for atmospheric scattering, which typically contributes ≥85% to the top-of-atmosphere (TOA) radiance and varies substantially with aerosols. Ocean color missions traditionally analyze TOA radiance in the near-infrared (NIR), where the ocean is black, to constrain the TOA atmospheric scattering in the visible (VIS). However, this procedure is limited by insufficient sensitivity of NIR radiance to absorption and vertical distribution of aerosols, and by uncertainties in the extrapolation of aerosol properties from the NIR to the VIS. To improve atmospheric correction for ocean color observations, one needs to change the traditional procedure for this correction and/or increase the aerosol information. The instruments proposed for the Pre-Aerosol, Clouds, and ocean Ecosystem (PACE) mission include ultraviolet and Oxygen A-band observations, as well as multispectral and multiangle polarimetry, to increase the aerosol information content. However no studies have been performed on whether such observations contain sufficient aerosol information, and on how to use this information, to substantially improve atmospheric correction. To study the atmospheric correction capabilities of PACE-like instruments, we are conducting field experiments off the Coast of California to obtain high-altitude airborne and in-situ observations of water-leaving radiance. The airborne data sets consist of hyperspectral radiance between 380-2500 nm by the Airborne Visible/Infrared Imaging Spectrometer, and narrow-band multiangle polarimetric data between 410-2250 nm by the Research Scanning Polarimeter. We discuss the quality of and comparisons between these data sets, and their differential sensitivities to variations in aerosol properties and ocean color.

  6. Environmental Public Health Survelliance for Exposure to Respiratory Health Hazards: A Joint NASA/CDC Project to Use Remote Sensing Data for Estimating Airborne Particulate Matter Over the Atlanta, Georgia Metropolitan Area

    NASA Technical Reports Server (NTRS)

    Quattrochi, Dale A.; Rickman, Douglas; Mohammad, Al-Hamdan; Crosson, William; Estes, Maurice, Jr.; Limaye, Ashutosh; Qualters, Judith

    2008-01-01

    Describes the public health surveillance efforts of NASA, in a joint effort with the Center for Disease Control (CDC). NASA/MSFC and the CDC are partners in linking nvironmental and health data to enhance public health surveillance. The use of NASA technology creates value - added geospatial products from existing environmental data sources to facilitate public health linkages. The venture sought to provide remote sensing data for the 5-country Metro-Atlanta area and to integrate this environmental data with public health data into a local network, in an effort to prevent and control environmentally related health effects. Remote sensing data used environmental data (Environmental Protection Agency [EPA] Air Quality System [AQS] ground measurements and MODIS Aerosol Optical Depth [AOD]) to estimate airborne particulate matter over Atlanta, and linked this data with health data related to asthma. The study proved the feasibility of linking environmental data (MODIS particular matter estimates and AQS) with health data (asthma). Algorithms were developed for QC, bias removal, merging MODIS and AQS particulate matter data, as well as for other applications. Additionally, a Business Associate Agreement was negotiated for a health care provider to enable sharing of Protected Health Information.

  7. A Melting Layer Model for Passive/Active Microwave Remote Sensing Applications. Part 2; Simulation of TRMM Observations

    NASA Technical Reports Server (NTRS)

    Olson, William S.; Bauer, Peter; Kummerow, Christian D.; Tao, Wei-Kuo

    2000-01-01

    The one-dimensional, steady-state melting layer model developed in Part I of this study is used to calculate both the microphysical and radiative properties of melting precipitation, based upon the computed concentrations of snow and graupel just above the freezing level at applicable horizontal gridpoints of 3-dimensional cloud resolving model simulations. The modified 3-dimensional distributions of precipitation properties serve as input to radiative transfer calculations of upwelling radiances and radar extinction/reflectivities at the TRMM Microwave Imager (TMI) and Precipitation Radar (PR) frequencies, respectively. At the resolution of the cloud resolving model grids (approx. 1 km), upwelling radiances generally increase if mixed-phase precipitation is included in the model atmosphere. The magnitude of the increase depends upon the optical thickness of the cloud and precipitation, as well as the scattering characteristics of ice-phase precipitation aloft. Over the set of cloud resolving model simulations utilized in this study, maximum radiance increases of 43, 28, 18, and 10 K are simulated at 10.65, 19.35 GHz, 37.0, and 85.5 GHz, respectively. The impact of melting on TMI-measured radiances is determined not only by the physics of the melting particles but also by the horizontal extent of the melting precipitation, since the lower-frequency channels have footprints that extend over 10''s of kilometers. At TMI resolution, the maximum radiance increases are 16, 15, 12, and 9 K at the same frequencies. Simulated PR extinction and reflectivities in the melting layer can increase dramatically if mixed-phase precipitation is included, a result consistent with previous studies. Maximum increases of 0.46 (-2 dB) in extinction optical depth and 5 dBZ in reflectivity are simulated based upon the set of cloud resolving model simulations.

  8. Estimating the spatial distribution of evapotranspiration using the water balance model WAVE and fine spatial resolution airborne remote sensing images from the DAIS-sensor: Experimental set-up

    NASA Astrophysics Data System (ADS)

    Verstraeten, W. W.; Veroustraete, F.; Feyen, J.

    2003-04-01

    Actual evapotranspiration (ET) of agricultural land and forestland surfaces play an important role in the redistribution of water on the Earth's surface. Any change in evapotranspiration, either through change in vegetation or climate change, directly effects the available water resources. For quantifying these effects physical models need to be constructed. Most hydrological models have to deal with a lack of good spatial resolution, despite their good temporal information. Remote sensing techniques on the contrary determine the spatial pattern of landscape features and hence are very useful on large scales. The main objective of this research is the combination of the spatial pattern of remote sensing (using visible and thermal infrared spectrum) with the temporal pattern of the water balance model WAVE (Vanclooster et al., 1994 and 1996). To realise this, the following objectives are formulated: (i) relate soil and vegetation surface temperatures to actual evapotranspiration of forest and crops simulated with the water balance model WAVE using remote sensing derived parameters. Three methods will be used and mutually compared. Both airborne and satellite imagery will be implemented; (1) compare the spatial pattern of evapotranspiration, as a result of the three methods, with the energy balance model SEBAL (Bastiaanssen et al., 1998) and finally; (2) subject the up-scaled WAVE and SEBAL models to an uncertainty analysis using the GLUE-approach (Generalised Likelihood Uncertainty Estimate) (Beven en Binley, 1992). To study the behaviour of the model beyond the field-scale (micro-scale), a meso-scale study was conducted at the test-site of DURAS (50°50'38"N, 5°08'50"W, Sint-Truiden). Airborne imagery from the DAIS/ROSIS sensor are available. For the determination of the spatial pattern of actual evapotranspiration the next two methods are considered: (1) relations between surface temperature, surface albedo and vegetation indices are linked with field

  9. WHICH AIRBORNE CONTAMINANTS POSE THE GREATEST RISK TO WESTERN NATIONAL PARKS (USA)?

    EPA Science Inventory

    The Western Airborne Contaminants Assessment Project (WACAP) was initiated in 2002 by the National Park Service to determine if airborne contaminants where having an impact on remote western ecosystems. Multiple sample media (snow, water, sediment, fish and terrestrial vegetatio...

  10. AIRBORNE CONTAMINANTS IN WESTERN NORTH AMERICAN NATIONAL PARKS--WHAT WE KNOW AND WANT TO LEARN

    EPA Science Inventory

    The National Park Service initiated the Western Airborne Contaminants Assessment Project (WACAP) in 2002 to determine if airborne contaminants from regional or distant sources have an impact on remote (typically high elevation) western ecosystems, including Alaska. Eight Nationa...

  11. Passive microwave soil moisture research

    NASA Technical Reports Server (NTRS)

    Schmugge, T. J.; Oneill, P. E.; Wang, J. R.

    1985-01-01

    The AgRISTARS Soil Moisture Project has made significant progress in the quantification of microwave sensor capabilities for soil moisture remote sensing. The 21-cm wavelength has been verified to be the best single channel for radiometric observations of soil moisture. It has also been found that other remote sensing approaches used in conjunction with L-band passive data are more successful than multiple wavelength microwave radiometry in this application. AgRISTARS studies have also improved current understanding of noise factors affecting the interpretability of microwave emission data. The absorption of soil emission by vegetation has been quantified, although this effect is less important than absorption effects for microwave radiometry.

  12. Characterizing fire-related spatial patterns in fire-prone ecosystems using optical and microwave remote sensing

    NASA Astrophysics Data System (ADS)

    Henry, Mary Catherine

    The use of active and passive remote sensing systems for relating forest spatial patterns to fire history was tested over one of the Arizona Sky Islands. Using Landsat Thematic Mapper (TM), Shuttle Imaging Radar (SIR-C), and data fusion I examined the relationship between landscape metrics and a range of fire history characteristics. Each data type (TM, SIR-C, and fused) was processed in the following manner: each band, channel, or derived feature was simplified to a thematic layer and landscape statistics were calculated for plots with known fire history. These landscape metrics were then correlated with fire history characteristics, including number of fire-free years in a given time period, mean fire-free interval, and time since fire. Results from all three case studies showed significant relationships between fire history and forest spatial patterns. Data fusion performed as well or better than Landsat TM alone, and better than SIR-C alone. These comparisons were based on number and strength of significant correlations each method achieved. The landscape metric that was most consistent and obtained the greatest number of significant correlations was Shannon's Diversity Index. Results also agreed with field-based research that has linked higher fire frequency to increased landscape diversity and patchiness. An additional finding was that the fused data seem to detect fire-related spatial patterns over a range of scales.

  13. Separability of agricultural crops with airborne scatterometry

    NASA Technical Reports Server (NTRS)

    Mehta, N. C.

    1983-01-01

    Backscattering measurements were acquired with airborne scatterometers over a site in Cass County, North Dakota on four days in the 1981 crop growing season. Data were acquired at three frequencies (L-, C- and Ku-bands), two polarizations (like and cross) and ten incidence angles (5 degrees to 50 degrees in 5 degree steps). Crop separability is studied in an hierarchical fashion. A two-class separability measure is defined, which compares within-class to between-class variability, to determine crop separability. The scatterometer channels with the best potential for crop separability are determined, based on this separability measure. Higher frequencies are more useful for discriminating small grains, while lower frequencies tend to separate non-small grains better. Some crops are more separable when row direction is taken into account. The effect of pixel purity is to increase the separability between all crops while not changing the order of useful scatterometer channels. Crude estimates of separability errors are calculated based on these analyses. These results are useful in selecting the parameters of active microwave systems in agricultural remote sensing.

  14. Airborne Demonstration of Microwave and Wide-Band Millimeter-Wave Radiometers to Provide High-Resolution Wet-Tropospheric Path Delay Corrections for Coastal and Inland Water Altimetry

    NASA Astrophysics Data System (ADS)

    Reising, Steven; Kangaslahti, Pekka; Tanner, Alan; Padmanabhan, Sharmila; Montes, Oliver; Parashare, Chaitali; Bosch-Lluis, Xavier; Hadel, Victoria; Johnson, Thaddeus; Brown, Shannon; Khayatian, Behrouz; Dawson, Douglas; Gaier, Todd; Razavi, Behzad

    2014-05-01

    Current satellite ocean altimeters include nadir-viewing, co-located 18-34 GHz microwave radiometers to measure wet-tropospheric path delay. Due to the size of the surface instantaneous fields of view (IFOV) at these frequencies, the accuracy of wet path retrievals is substantially degraded near coastlines, and retrievals are not provided over land. Retrievals are flagged as not useful within approximately 40 km of the world's coastlines. A viable approach to improve their capability is to add wide-band high-frequency millimeter-wave window channels in the 90-180 GHz band, thereby achieving finer spatial resolution for a limited antenna size. In this context, the upcoming NASA/CNES/CSA Surface Water and Ocean Topography (SWOT) mission is in formulation and planned for launch in late 2020. The primary objectives of SWOT are to characterize ocean mesoscale and sub-mesoscale processes on 10-km and larger scales in the global oceans and provide measurements of the global water storage in inland surface water bodies and the flow rate of rivers. Therefore, an important new science objective of SWOT is to transition satellite altimetry from the open ocean into the coastal zone and over inland water. The addition of 90-180 GHz millimeter-wave window-channel radiometers to current Jason-class 18-34 GHz radiometers is expected to improve retrievals of wet-tropospheric delay in coastal areas and to enhance the potential for over-land retrievals. In 2012 the Ocean Surface Topography Science Team Meeting recommended to add high-frequency millimeter-wave radiometers to the Jason Continuity of Service (CS) mission. To reduce the risks of wet-tropospheric path delay measurement over coastal areas and inland water bodies, we have designed, developed and fabricated a new airborne radiometer, combining three high-frequency millimeter-wave window channels at 90, 130 and 168 GHz, along with Jason-series microwave channels at 18.7, 23.8 and 34.0 GHz, and validation channels sounding

  15. Snow depth retrieval algorithm of saline-alkali land in the western Jilin Province of China using passive microwave remote sensing data

    NASA Astrophysics Data System (ADS)

    Sun, Mingbo; Gu, Lingjia; Ren, Ruizhi; Fu, Haoyang

    2015-09-01

    The western region of Jilin Province is an important part of fragile ecological environment in Northeast China where the soil salinization problem is particularly obvious. Meanwhile, it belongs to a typical snow-covered area and has a northerly continental monsoon climate, with long, cold winters and short, warm summers. It has one single large snowfall period of six month. Therefore, in this paper, the western Jilin Province was selected as the study area and divided into five land surface types including water bodies, grassland, farmland, slight saline-alkali land, moderate and severe saline-alkali land. Furthermore, the two snow depth retrieval algorithms of Chang algorithm and FY3B operational retrieval algorithm were validated and analyzed by using FY-3B/MWRI passive microwave remote sensing data. The main research focused on the analysis of the snow depth covered on the other four different land surface types except water bodies. Based on the five years' observation data from 2011 to 2015, the changes of snow depth on the four land surface types were analyzed and compared with that of MODIS 09A1 snow cover data. The analysis results demonstrated that the snow depth in farmland type is greater than that in grassland type. In addition, the snow depth in slight saline-alkali land type is greater than that in the moderate and severe saline-alkali land type. The study results also showed that the snow depth of Chang's algorithm is more accurate than that of FY3B operational retrieval algorithm in the study area. This research provided important information to the research of snow depth in saline-alkali land area.

  16. Airborne Imagery

    NASA Technical Reports Server (NTRS)

    1983-01-01

    ATM (Airborne Thematic Mapper) was developed for NSTL (National Space Technology Companies) by Daedalus Company. It offers expanded capabilities for timely, accurate and cost effective identification of areas with prospecting potential. A related system is TIMS, Thermal Infrared Multispectral Scanner. Originating from Landsat 4, it is also used for agricultural studies, etc.

  17. Airborne lidar experiments at the Savannah River Plant

    NASA Technical Reports Server (NTRS)

    Krabill, William B.; Swift, Robert N.

    1985-01-01

    The results of remote sensing experiments at the Department of Energy (DOE) Savannah River Nuclear Facility utilizing the NASA Airborne Oceanographic Lidar (AOL) are presented. The flights were conducted in support of the numerous environmental monitoring requirements associated with the operation of the facility and for the purpose of furthering research and development of airborne lidar technology. Areas of application include airborne laser topographic mapping, hydrologic studies using fluorescent tracer dye, timber volume estimation, baseline characterization of wetlands, and aquatic chlorophyll and photopigment measurements. Conclusions relative to the usability of airborne lidar technology for the DOE for each of these remote sensing applications are discussed.

  18. Remote Sensing of the Arctic Seas.

    ERIC Educational Resources Information Center

    Weeks, W. F.; And Others

    1986-01-01

    Examines remote sensing of the arctic seas by discussing: (1) passive microwave sensors; (2) active microwave sensors; (3) other types of sensors; (4) the future deployment of sensors; (5) data buoys; and (6) future endeavors. (JN)

  19. Investigation of airborne lidar for avoidance of windshear hazards

    NASA Technical Reports Server (NTRS)

    Targ, Russell; Bowles, Roland L.

    1990-01-01

    A generalized windshear hazard index is defined, which is derived from considerations of wind conditions at the present position of an aircraft and from remotely sensed information along the extended flight path. Candidate airborne sensor technologies based on microwave Doppler radar, Doppler lidar, and infrared radiometric techniques are discussed in the context of overall system functional requirements. Initial results of a performance and technology assessment study for competing lidars are presented. Based on a systems approach to the windshear threat, lidar appears to be a viable technology for windshear detection and avoidance, even in conditions of moderately heavy precipitation. The proposed airborne CO2 and Ho:YAG lidar windshear-detection systems analyzed here can give the pilot information about the line-of-sight component of windshear threat from his present position to a region extending 1 to 3 km in front of the aircraft. This constitutes a warning time of 15 to 45 seconds. The technology necessary to design, build, and test such a brassboard 10.6 micron CO2 lidar is now available. However, for 2-micron systems, additional analytical and laboratory investigations are needed to arrive at optimum 2-micron rare-earth-based laser crystals.

  20. Remote sensing at Savannah River

    SciTech Connect

    Corey, J.C.

    1986-01-01

    The paper discusses remote sensing systems used at the Savannah River Plant. They include three ground-based systems: ground penetrating radar, sniffers, and lasers; and four airborne systems: multispectral photography, lasers, thermal imaging, and radar systems. (ACR)

  1. Spaceborne Microwave Imagers

    NASA Technical Reports Server (NTRS)

    Stacey, J. M.

    1991-01-01

    Monograph presents comprehensive overview of science and technology of spaceborne microwave-imaging systems. Microwave images used as versatile orbiting, remote-sensing systems to investigate atmospheres and surfaces of planets. Detect surface objects through canopies of clouds, measure distributions of raindrops in clouds that their views penetrate, find meandering rivers in rain forests and underground water in arid regions, and provide information on ocean currents, wakes, ice/water boundaries, aircraft, ships, buoys, and bridges.

  2. Microwave hydrology: A trilogy

    NASA Technical Reports Server (NTRS)

    Stacey, J. M.; Johnston, E. J.; Girard, M. A.; Regusters, H. A.

    1985-01-01

    Microwave hydrology, as the term in construed in this trilogy, deals with the investigation of important hydrological features on the Earth's surface as they are remotely, and passively, sensed by orbiting microwave receivers. Microwave wavelengths penetrate clouds, foliage, ground cover, and soil, in varying degrees, and reveal the occurrence of standing liquid water on and beneath the surface. The manifestation of liquid water appearing on or near the surface is reported by a microwave receiver as a signal with a low flux level, or, equivalently, a cold temperature. Actually, the surface of the liquid water reflects the low flux level from the cosmic background into the input terminals of the receiver. This trilogy describes and shows by microwave flux images: the hydrological features that sustain Lake Baykal as an extraordinary freshwater resource; manifestations of subsurface water in Iran; and the major water features of the Congo Basin, a rain forest.

  3. Geophex airborne unmanned survey system

    SciTech Connect

    Won, I.J.; Taylor, D.W.A.

    1995-03-01

    The purpose of this effort is to design, construct, and evaluate a portable, remotely-piloted, airborne, geophysical survey system. This nonintrusive system will provide {open_quotes}stand-off{close_quotes} capability to conduct surveys and detect buried objects, structures, and conditions of interest at hazardous locations. This system permits two operators to rapidly conduct geophysical characterization of hazardous environmental sites. During a survey, the operators remain remote from, but within visual distance, of, the site. The sensor system never contacts the Earth, but can be positioned near the ground so that weak anomalies can be detected.

  4. Geophex Airborne Unmanned Survey System

    SciTech Connect

    Won, I.J.; Keiswetter, D.

    1995-10-01

    The purpose of this effort is to design, construct, and evaluate a portable, remotely-piloted, airborne, geophysical survey system. This non-intrusive system will provide {open_quotes}stand-off{close_quotes} capability to conduct surveys and detect buried objects, structures, and conditions of interest at hazardous locations. This system permits rapid geophysical characterization of hazardous environmental sites. During a survey, the operators remain remote from, but within visual distance of, the site. The sensor system never contacts the Earth, but can be positioned near the ground so that weak geophysical anomalies can be detected.

  5. Fluid Lensing, Applications to High-Resolution 3D Subaqueous Imaging & Automated Remote Biosphere Assessment from Airborne and Space-borne Platforms

    NASA Astrophysics Data System (ADS)

    Chirayath, V.

    2014-12-01

    Fluid Lensing is a theoretical model and algorithm I present for fluid-optical interactions in turbulent flows as well as two-fluid surface boundaries that, when coupled with an unique computer vision and image-processing pipeline, may be used to significantly enhance the angular resolution of a remote sensing optical system with applicability to high-resolution 3D imaging of subaqueous regions and through turbulent fluid flows. This novel remote sensing technology has recently been implemented on a quadcopter-based UAS for imaging shallow benthic systems to create the first dataset of a biosphere with unprecedented sub-cm-level imagery in 3D over areas as large as 15 square kilometers. Perturbed two-fluid boundaries with different refractive indices, such as the surface between the ocean and air, may be exploited for use as lensing elements for imaging targets on either side of the interface with enhanced angular resolution. I present theoretical developments behind Fluid Lensing and experimental results from its recent implementation for the Reactive Reefs project to image shallow reef ecosystems at cm scales. Preliminary results from petabyte-scale aerial survey efforts using Fluid Lensing to image at-risk coral reefs in American Samoa (August, 2013) show broad applicability to large-scale automated species identification, morphology studies and reef ecosystem characterization for shallow marine environments and terrestrial biospheres, of crucial importance to understanding climate change's impact on coastal zones, global oxygen production and carbon sequestration.

  6. Relations Between Cloud Condensation Nuclei And Aerosol Optical Properties Relevant to Remote Sensing: Airborne Measurements in Biomass Burning, Pollution and Dust Aerosol Over North America

    NASA Astrophysics Data System (ADS)

    Shinozuka, Y.; Clarke, A.; Howell, S.; Kapustin, V.; McNaughton, C.; Zhou, J.; Decarlo, P.; Jimenez, J.; Roberts, G.; Tomlinson, J.; Collins, D.

    2008-12-01

    Remote sensing of the concentration of cloud condensation nuclei (CCN) would help investigate the indirect effect of tropospheric aerosols on clouds and climate. In order to assess its feasibility, this paper evaluates the spectral-based retrieval technique for aerosol number and seeks one for aerosol solubility, using in-situ aircraft measurements of aerosol size distribution, chemical composition, hygroscopicity, CCN activity and optical properties. Our statistical analysis reveals that the CCN concentration over Mexico can be optically determined to a relative error of <20%, smaller than that for the mainland US and the surrounding oceans (~a factor of 2). Mexico's advantage is four-fold. Firstly, many particles originating from the lightly regulated industrial combustion and biomass burning are large enough to significantly affect light extinction, elevating the correlation between extinction and CCN number in absence of substantial dust. Secondly, the generally low ambient humidity near the major aerosol sources limits the error in the estimated response of particle extinction to humidity changes. Thirdly, because many CCN contain black carbon, light absorption also provides a measure of the CCN concentration. Fourthly, the organic fraction of volatile mass of submicron particles (OMF) is anti-correlated with the wavelength dependence of extinction due to preferential anion uptake by coarse dust, which provides a potential tool for remote-sensing OMF and the particle solubility.

  7. Remote sensing and image interpretation

    NASA Technical Reports Server (NTRS)

    Lillesand, T. M.; Kiefer, R. W. (Principal Investigator)

    1979-01-01

    A textbook prepared primarily for use in introductory courses in remote sensing is presented. Topics covered include concepts and foundations of remote sensing; elements of photographic systems; introduction to airphoto interpretation; airphoto interpretation for terrain evaluation; photogrammetry; radiometric characteristics of aerial photographs; aerial thermography; multispectral scanning and spectral pattern recognition; microwave sensing; and remote sensing from space.

  8. Remote Sensing of Liquid Water and Ice Cloud Optical Thickness and Effective Radius in the Arctic: Application of Airborne Multispectral MAS Data

    NASA Technical Reports Server (NTRS)

    King, Michael D.; Platnick, Steven; Yang, Ping; Arnold, G. Thomas; Gray, Mark A.; Riedi, Jerome C.; Ackerman, Steven A.; Liou, Kuo-Nan

    2003-01-01

    A multispectral scanning spectrometer was used to obtain measurements of the reflection function and brightness temperature of clouds, sea ice, snow, and tundra surfaces at 50 discrete wavelengths between 0.47 and 14.0 microns. These observations were obtained from the NASA ER-2 aircraft as part of the FIRE Arctic Clouds Experiment, conducted over a 1600 x 500 km region of the north slope of Alaska and surrounding Beaufort and Chukchi Seas between 18 May and 6 June 1998. Multispectral images of the reflection function and brightness temperature in 11 distinct bands of the MODIS Airborne Simulator (MAS) were used to derive a confidence in clear sky (or alternatively the probability of cloud), shadow, and heavy aerosol over five different ecosystems. Based on the results of individual tests run as part of the cloud mask, an algorithm was developed to estimate the phase of the clouds (water, ice, or undetermined phase). Finally, the cloud optical thickness and effective radius were derived for both water and ice clouds that were detected during one flight line on 4 June. This analysis shows that the cloud mask developed for operational use on MODIS, and tested using MAS data in Alaska, is quite capable of distinguishing clouds from bright sea ice surfaces during daytime conditions in the high Arctic. Results of individual tests, however, make it difficult to distinguish ice clouds over snow and sea ice surfaces, so additional tests were added to enhance the confidence in the thermodynamic phase of clouds over the Beaufort Sea. The cloud optical thickness and effective radius retrievals used 3 distinct bands of the MAS, with the newly developed 1.62 and 2.13 micron bands being used quite successfully over snow and sea ice surfaces. These results are contrasted with a MODIS-based algorithm that relies on spectral reflectance at 0.87 and 2.13 micron.

  9. Retrieval of spinach crop parameters by microwave remote sensing with back propagation artificial neural networks: A comparison of different transfer functions

    NASA Astrophysics Data System (ADS)

    Prasad, Rajendra; Pandey, A.; Singh, K. P.; Singh, V. P.; Mishra, R. K.; Singh, D.

    2012-08-01

    Back propagation artificial natural network (BPANN) is a well known and widely used machine learning methodology in the field of remote sensing. In this paper an attempt is made to retrieve the spinach crop parameters like biomass, leaf area index, average plant height and soil moisture content by using the X-band scattering coefficients with BPANN at different growth stages of this crop. The maturity age of this crop was found to be 45 days from the date of sowing. After 45 days from the date of sowing, this crop was cut at a certain height for production. Then, it is a point of interest to investigate the microwave response of variation in production. Significant variations in all the crop parameters were observed after cutting the crop and consequently made the problem more critical. Our work confirms the utility of BPANN in handling such a non-linear data set. The BPANN is essentially a network of simple processing nodes arranged into different layers as input, hidden and the output. The input layer propagates components of a particular input vector after weighting these with synaptic weights to each node in the hidden layer. At each node, these weighted input vector components are added. Each hidden layer computes output corresponding to these weighted sum through a non-linear/linear function (e.g. LOGSIG, TANSIG and PURLIN). These functions are known as transfer functions. Thus, each of the hidden layer nodes compute output values, which become inputs to the nodes of the output layer. At nodes of output layer also a weighted sum of outputs of previous layer (hidden layer) are obtained and processed through a transfer function. Thus, the output layer nodes compute the network output for the particular input vector. In this paper, output nodes use linear transfer function. Different transfer functions e.g. TANSIG, LOGSIG and PURELIN were used and the performance of the ANN was optimized by changing the number of neurons in the hidden layers. The present

  10. Passive/active microwave soil moisture retrieval disaggregation using SMAPVEX12 data

    NASA Astrophysics Data System (ADS)

    Fang, Bin; Lakshmi, Venkat

    2014-11-01

    SMAPVEX12 is a pre-launch field campaign for evaluating and testing the soil moisture retrievals retrieved from the SMAP project. During this experiment, airborne microwave observations from PALS radiometer and radar: brightness temperature and radar backscatter, as well as ground measurements were acquired. In this study, the remote sensing soil moisture was retrieved from SMAPVEX12 PALS radiometer L-band (6GHz) brightness temperature at high altitude flight. The PALS soil moisture was then aggregated and compared with PALS radar backscatter coefficient to generate high spatial resolution microwave soil moisture in change. The R2 values of PALS soil moisture retrieval validation range from 0.407-0.881, indicating good accuracy of soil moisture retrieval. The R2 values of comparison between aggregated PALS Δ and PALS Δ range from 0.492-0.805, while the downscaled Δ validation range from 0.128- 0.383.

  11. Remote sensing of the earth's surface; Proceedings of the Symposium 2, Topical Meeting, and Workshop I of the 27th COSPAR Plenary Meeting, Espoo, Finland, July 18-29, 1988

    NASA Technical Reports Server (NTRS)

    Salomonson, V. V. (Editor); Walter, L. S. (Editor); Maetzler, C. (Editor); Rott, H. (Editor)

    1989-01-01

    The present conference discusses topics in the spaceborne study of the earth's surface, crust, and lithosphere, recent results from SPOT and Landsat TM investigations, and microwave observations of snowpack and soil properties. Attention is given to airborne and satellite-borne gravimetry, stereoviewing from space, TM studies of volcanism and tectonism in central Mexico, remote sensing of volcanoes, the uses of SPOT in forest management, the tectonics of the central Andes, and the application of VLBI to crustal movement studies. Also discussed are Landsat TM band ratios for soil investigations, snow dielectric measurements, the microwave radiometry of snow, microwave signatures of bare soil, the estimation of Alpine snow properties from Landsat TM data, and an experimental study of vegetable canopy microwave emissions.

  12. Progress Towards the Remote Sensing of Aircraft Icing Hazards

    NASA Technical Reports Server (NTRS)

    Reehorst, Andrew; Brinker, David; Politovich, Marcia; Serke, David; Ryerson, Charles; Pazmany, Andrew; Solheim, Fredrick

    2009-01-01

    NASA has teamed with the FAA, DoD, industry, and academia for research into the remote detection and measurement of atmospheric conditions leading to aircraft icing hazards. The ultimate goal of this effort is to provide pilots, controllers, and dispatchers sufficient information to allow aircraft to avoid or minimize their exposure to the hazards of in-flight icing. Since the hazard of in-flight icing is the outcome of aircraft flight through clouds containing supercooled liquid water and strongly influenced by the aircraft s speed and configuration and by the length of exposure, the hazard cannot be directly detected, but must be inferred based upon the measurement of conducive atmospheric conditions. Therefore, icing hazard detection is accomplished through the detection and measurement of liquid water in regions of measured sub-freezing air temperatures. The icing environment is currently remotely measured from the ground with a system fusing radar, lidar, and multifrequency microwave radiometer sensors. Based upon expected ice accretion severity for the measured environment, a resultant aircraft hazard is then calculated. Because of the power, size, weight, and view angle constraints of airborne platforms, the current ground-based solution is not applicable for flight. Two current airborne concepts are based upon the use of either multifrequency radiometers or multifrequency radar. Both ground-based and airborne solutions are required for the future since groundbased systems can provide hazard detection for all aircraft in airport terminal regions while airborne systems will be needed to provide equipped aircraft with flight path coverage between terminal regions.

  13. Characterization of shallow marine convection in subtropical regions by airborne and spaceborne lidar measurements

    NASA Astrophysics Data System (ADS)

    Gross, Silke; Gutleben, Manuel; Schäfler, Andreas; Kiemle, Christoph; Wirth, Martin; Hirsch, Lutz; Ament, Felix

    2016-04-01

    One of the biggest challenges in present day climate research is still the quantification of cloud feedbacks in climate models. Especially the feedback from marine cumulus clouds in the boundary layer with maximum cloud top heights of 4 km introduces large uncertainties in climate sensitivity. Therefore a better understanding of these shallow marine clouds, as well as of their interaction with aerosols and the Earth's energy budget is demanded. To improve our knowledge of shallow marine cumulus convection, measurements onboard the German research aircraft HALO were performed during the NARVAL (Next-generation Aircraft Remote-sensing for Validation studies) mission in December 2013. During NARVAL an EarthCARE equivalent remote sensing payload, with the DLR airborne high spectral resolution and differential absorption lidar system WALES and the cloud radar of the HAMP (HALO Microwave Package) as its core instrumentation, was deployed. To investigate the capability of spaceborne lidar measurements for this kind of study several CALIOP underflights were performed. We will present a comparison of airborne and spaceborne lidar measurements, and we will present the vertical and horizontal distribution of the clouds during NARVAL based on lidar measurements. In particular we investigate the cloud top distribution and the horizontal cloud and cloud gap length. Furthermore we study the representativeness of the NARVAL data by comparing them to and analysing a longer time series and measurements at different years and seasons.

  14. Temperature monitoring along the Rhine River based on airborne thermal infrared remote sensing: qualitative results compared to satellite data and validation with in situ measurements

    NASA Astrophysics Data System (ADS)

    Fricke, Katharina; Baschek, Björn

    2014-10-01

    Water temperature is an important parameter of water quality and influences other physical and chemical parameters. It also directly influences the survival and growth of animal and plant species in river ecosystems. In situ measurements do not allow for a total spatial coverage of water bodies and rivers that is necessary for monitoring and research at the Federal Institute of Hydrology (BfG), Germany. Hence, the ability of different remote sensing products to identify and investigate water inflows and water temperatures in Federal waterways is evaluated within the research project 'Remote sensing of water surface temperature'. The research area for a case study is the Upper and Middle Rhine River from the barrage in Iffezheim to Koblenz. Satellite products (e. g. Landsat and ASTER imagery) can only be used for rivers at least twice as wide as the spatial resolution of the satellite images. They can help to identify different water bodies only at tributaries with larger inflow volume (Main and Mosel) or larger temperature differences between the inflow (e. g. from power plants working with high capacity) and the river water. To identify and investigate also smaller water inflows and temperature differences, thermal data with better ground and thermal resolution is required. An aerial survey of the research area was conducted in late October 2013. Data of the surface was acquired with two camera systems, a digital camera with R, G, B, and Near-IR channels, and a thermal imaging camera measuring the brightness temperature in the 8-12 m wavelength region (TIR). The resolution of the TIR camera allowed for a ground resolution of 4 m, covering the whole width of the main stream and larger branches. The RGB and NIR data allowed to eliminate land surface temperatures from the analysis and to identify clouds and shadows present during the data acquisition. By degrading the spatial resolution and adding sensor noise, artificial Landsat ETM+ and TIRS datasets were created

  15. The Split Window Microwave Radiometer (SWMR) for hurricane wind speed measurement from space

    NASA Technical Reports Server (NTRS)

    Swift, Calvin T.; Black, P. G.

    1992-01-01

    The monitoring of hurricanes demands considerable resources each year by the National Oceanic and Atmospheric Administration. Even with the extensive use of satellite and airborne probing of those storms, there is still much uncertainty involved in predicting landfall for timely evacuation of people subject to the threat. The concept of the Split Window Microwave Radiometer (SWMR) is to add an additional capability of remotely measuring surface winds to hopefully improve prediction capabilities or at least define the severity of the storm while it is far from land. Some of the present science and observational needs are addressed in this report as are remote sensing limitations which impact the design of a minimal system which can be launched into low earth orbit by a low cost launch system. This study has concluded that wind speed and rain rate maps of hurricanes can be generated with an X-Band radiometer system with an antenna whose aperture is 2 m on a side.

  16. Microwave sensing from orbit

    NASA Technical Reports Server (NTRS)

    Kritikos, H. N.; Shiue, J.

    1979-01-01

    Microwave sensors, used in conjunction with the traditional sensors of visible and infrared light to extend present capabilities of global weather forecasts and local storm watches, are discussed. The great advantage of these sensors is that they can penetrate or 'see' through cloud formations to monitor temperature, humidity and wind fields below the clouds. Other uses are that they can penetrate the earth deeper than optical and IR systems; they can control their own angle of incidence; they can detect oil spills; and they can enhance the studies of the upper atmosphere through measurement of temperature, water vapor and other gaseous species. Two types of microwave sensors, active and passive, are examined. Special attention is given to the study of the microwave radiometer and the corresponding temperature resolution as detected by the antenna. It is determined that not only will the microwave remote sensors save lives by allowing close monitoring of developing storms, but also save approximately $172 million/year.

  17. Airborne and ground-based remote sensing for the estimation of evapotranspiration and yield of bean, potato, and sugar beet crops

    NASA Astrophysics Data System (ADS)

    Jayanthi, Harikishan

    compared with the actual yields extracted from the ground. The remote sensing-derived yields compared well with the actual yields sampled on the ground. This research has highlighted the importance of the date of spectral emergence, the need to know the duration for which the crops stand on the ground, and the need to identify critical periods of time when multispectral coverages are essential for reliable tuber yield estimation.

  18. Evaluation of a Modified SEBAL Algorithm to Estimate Actual Evapotranspiration in Cotton Ecosystems of Central Asia using Microwave and Optical Remote Sensing Data

    NASA Astrophysics Data System (ADS)

    Knoefel, Patrick; Conrad, Christopher

    2015-04-01

    Being recognized as an essential component of both the water and the energy cycle, actual evapotranspiration (ETa) plays in important role in order to describe the complex interactions within the climate system of the Earth. Here, remote sensing is a powerful tool to estimate regional ETa to support the regional water management. For instance, the water withdrawal of the agricultural sector in OECD countries is on average about 44 %, but in the states of Central Asia it achieves more than 90 %. This fact is identified as one of the main reasons for the increasing water scarcity in this region. An accuracy assessment of the methods used for determining ETa is necessary concerning an appropriate use of the model results to support agriculture and irrigation management. Within Central Asia the Khorezm region in Uzbekistan is a case study region for the problems of irrigated agriculture. For Khorezm the seasonal ETa based on MODIS data was calculated for the years 2009 - 2011 using a partly modified surface energy balance algorithm for land (SEBAL). SEBAL was implemented based on MODIS time series to calculate the energy balance components like net radiation (Rn), sensible heat (H), latent heat (LE), and soil heat flux (G). Whilst SEBAL is using an empirical equation for the estimation of G, a more physically based method was introduced in this study. This method uses microwave soil moisture products (ASAR and ASCAT-SSM) as an additional model input. The input parameters and the model results of all energy balance components (Rn, H, LE, and G) were intensively validated by field measurements with an eddy covariance system and soil sensors. The model shows very good performance for Rn with average model efficiency (NSE) of 0.68 and small relative errors (rRMSE) of about 10%. For turbulent heat fluxes good results can be achieved with NSE of 0.31 for H and 0.55 for LE, the rRMSE are about 21% (H) and 18% (LE). Soil heat flux estimation could be improved using the

  19. Remote sensing of atmospheric water vapor, liquid water and wind speed at the ocean surface by passive microwave techniques from the Nimbus-5 satellite

    NASA Technical Reports Server (NTRS)

    Chang, A. T. C.; Wilheit, T. T.

    1977-01-01

    The microwave brightness temperature measurements for Nimbus-5 electrically scanned microwave radiometer and Nimbus E microwave spectrometer are used to retrieve the atmospheric water vapor, liquid water and wind speed by a quasi-statistical retrieval technique. It is shown that the brightness temperature can be utilized to yield these parameters under various weather conditions. Observations at 19.35 GHz, 22.235 GHz and 31.4 GHz were input to the regression equations. The retrieved values of these parameters for portions of two Nimbus-5 orbits are presented. Then comparison between the retrieved parameters and the available observations on the total water vapor content and the surface wind speed are made. The estimated errors for retrieval are approximately 0.15 g/sq cm for water vapor content, 6.5 mg/sq cm for liquid water content and 6.6 m/sec for surface wind speed.

  20. PHARUS airborne SAR concept

    NASA Astrophysics Data System (ADS)

    Snoeij, Paul; Pouwels, Henk; Koomen, Peter J.; Hoogeboom, Peter

    1995-11-01

    PHARUS (phased array universal SAR) is an airborne SAR concept which is being developed in the Netherlands. The PHARUS system differs from other airborne SARs by the use of a phased array antenna, which provides both for the flexibility in the design as well as for a compact, light-weight instrument that can be carried on small aircraft. The concept allows for the construction of airborne SAR systems on a common generic basis but tailored to specific user needs and can be seen as a preparation for future spaceborne SAR systems using solid state transmitters with electronically steerable phased array antenna. The whole approach is aimed at providing an economic and yet technically sophisticated solution to remote sensing or surveying needs of a specific user. The solid state phased array antenna consists of a collection of radiating patches; the design flexibility for a large part resides in the freedom to choose the number of patches, and thereby the essential radar performance parameters such as resolution and swath width. Another consequence of the use of the phased array antenna is the system's compactness and the possibility to rigidly mount it on a small aircraft. The use of small aircraft of course considerably improves the cost/benefit ratio of the use of airborne SAR. Flight altitude of the system is flexible between about 7,000 and 40,000 feet, giving much operational freedom within the meteo and airspace control limits. In the PHARUS concept the airborne segment is complemented by a ground segment, which consists of a SAR processor, possibly extended by a matching image processing package. (A quick look image is available in real-time on board the aircraft.) The SAR processor is UNIX based and runs on easily available hardware (SUN station). Although the additional image processing software is available, the SAR processing software is nevertheless designed to be able to interface with commercially available image processing software, as well as being able

  1. Geophex Airborne Unmanned Survey System

    SciTech Connect

    Won, I.L.; Keiswetter, D.

    1995-12-31

    Ground-based surveys place personnel at risk due to the proximity of buried unexploded ordnance (UXO) items or by exposure to radioactive materials and hazardous chemicals. The purpose of this effort is to design, construct, and evaluate a portable, remotely-piloted, airborne, geophysical survey system. This non-intrusive system will provide stand-off capability to conduct surveys and detect buried objects, structures, and conditions of interest at hazardous locations. During a survey, the operators remain remote from, but within visual distance of, the site. The sensor system never contacts the Earth, but can be positioned near the ground so that weak geophysical anomalies can be detected. The Geophex Airborne Unmanned Survey System (GAUSS) is designed to detect and locate small-scale anomalies at hazardous sites using magnetic and electromagnetic survey techniques. The system consists of a remotely-piloted, radio-controlled, model helicopter (RCH) with flight computer, light-weight geophysical sensors, an electronic positioning system, a data telemetry system, and a computer base-station. The report describes GAUSS and its test results.

  2. Towards GPS Surface Reflection Remote Sensing of Sea Ice Conditions

    NASA Technical Reports Server (NTRS)

    Komjathy, A.; Maslanik, J. A.; Zavorotny, V. U.; Axelrad, P.; Katzberg, S. J.

    2000-01-01

    This paper describes the research to extend the application of Global Positioning System (GPS) signal reflections, received by airborne instruments, to cryospheric remote sensing. The characteristics of the GPS signals and equipment afford the possibility of new measurements not possible with existing radar and passive microwave systems. In particular, the GPS receiving systems are small and light-weight, and as such are particularly well suited to be deployed on small aircraft or satellite platforms with minimal impact. Our preliminary models and experimental results indicate that reflected GPS signals have potential to provide information on the presence and condition of sea and fresh-water ice as well as the freeze/thaw state of frozen ground. In this paper we show results from aircraft experiments over the ice pack near Barrow, Alaska suggesting correlation between forward scattered GPS returns and RADARSAT backscattered signals.

  3. Passive Microwave Measurements of Salinity: The Gulf Stream Experiment

    NASA Technical Reports Server (NTRS)

    LeVine, D. M.; Koblinsky, C.; Haken, M.; Howden, S.; Bingham, F.; Hildebrand, Peter H. (Technical Monitor)

    2001-01-01

    Passive microwave sensors at L-band (1.4 GHz) operating from aircraft have demonstrated that salinity can be measured with sufficient accuracy (I psu) to be scientifically meaningful in coastal waters. However, measuring salinity in the open ocean presents unresolved issues largely because of the much greater accuracy (approximately 0.2 psu) required of global maps to be scientifically viable. The development of a satellite microwave instrument to make global measurements of SSS (Sea Surface Salinity) is the focus of a joint JPL/GSFC/NASA ocean research program called Aquarius. In the summer of 1999 a series of measurements called, The Gulf Stream Experiment, were conducted as part of research at the Goddard Space Flight Center to test the potential for passive microwave remote sensing of salinity in the open ocean. The measurements consisted of airborne microwave instruments together with ships and drifters for surface truth. The study area was a 200 km by 100 km rectangle about 250 km east of Delaware Bay between the continental shelf waters and north wall of the Gulf Stream. The primary passive instruments were the ESTAR radiometer (L-band, H-pol) and the SLFMR radiometer (L-band, V-pol). In addition, the instruments on the aircraft included a C-band radiometer (ACMR), an ocean wave scatterometer (ROWS) and an infrared radiometer (for surface temperature). These instruments were mounted on the NASA P-3 Orion aircraft. Sea surface measurements consisted of thermosalinograph data provided by the R/V Cape Henlopen and the MN Oleander, and data from salinity and temperature sensors on three surface drifters deployed from the R/V Cape Henlopen. The primary experiment period was August 26-September 2, 1999. During this period the salinity field within the study area consisted of a gradient on the order of 2-3 psu in the vicinity of the shelf break and a warm core ring with a gradient of 1-2 psu. Detailed maps were made with the airborne sensors on August 28 and 29 and

  4. Remote sensing of wetlands

    NASA Technical Reports Server (NTRS)

    Roller, N. E. G.

    1977-01-01

    The concept of using remote sensing to inventory wetlands and the related topics of proper inventory design and data collection are discussed. The material presented shows that aerial photography is the form of remote sensing from which the greatest amount of wetlands information can be derived. For extensive, general-purpose wetlands inventories, however, the use of LANDSAT data may be more cost-effective. Airborne multispectral scanners and radar are, in the main, too expensive to use - unless the information that these sensors alone can gather remotely is absolutely required. Multistage sampling employing space and high altitude remote sensing data in the initial stages appears to be an efficient survey strategy for gathering non-point specific wetlands inventory data over large areas. The operational role of remote sensing insupplying inventory data for application to several typical wetlands management problems is illustrated by summary descriptions of past ERIM projects.

  5. NASA's Coastal and Ocean Airborne Science Testbed

    NASA Astrophysics Data System (ADS)

    Guild, L. S.; Dungan, J. L.; Edwards, M.; Russell, P. B.; Morrow, J. H.; Hooker, S.; Myers, J.; Kudela, R. M.; Dunagan, S.; Soulage, M.; Ellis, T.; Clinton, N. E.; Lobitz, B.; Martin, K.; Zell, P.; Berthold, R. W.; Smith, C.; Andrew, D.; Gore, W.; Torres, J.

    2011-12-01

    The Coastal and Ocean Airborne Science Testbed (COAST) Project is a NASA Earth-science flight mission that will advance coastal ecosystems research by providing a unique airborne payload optimized for remote sensing in the optically complex coastal zone. Teaming NASA Ames scientists and engineers with Biospherical Instruments, Inc. (San Diego) and UC Santa Cruz, the airborne COAST instrument suite combines a customized imaging spectrometer, sunphotometer system, and a new bio-optical radiometer package to obtain ocean/coastal/atmosphere data simultaneously in flight for the first time. The imaging spectrometer (Headwall) is optimized in the blue region of the spectrum to emphasize remote sensing of marine and freshwater ecosystems. Simultaneous measurements supporting empirical atmospheric correction of image data will be accomplished using the Ames Airborne Tracking Sunphotometer (AATS-14). Based on optical detectors called microradiometers, the NASA Ocean Biology and Biogeochemistry Calibration and Validation (cal/val) Office team has deployed advanced commercial off-the-shelf instrumentation that provides in situ measurements of the apparent optical properties at the land/ocean boundary including optically shallow aquatic ecosystems (e.g., lakes, estuaries, coral reefs). A complimentary microradiometer instrument package (Biospherical Instruments, Inc.), optimized for use above water, will be flown for the first time with the airborne instrument suite. Details of the October 2011 COAST airborne mission over Monterey Bay demonstrating this new airborne instrument suite capability will be presented, with associated preliminary data on coastal ocean color products, coincident spatial and temporal data on aerosol optical depth and water vapor column content, as well as derived exact water-leaving radiances.

  6. Cloud top remote sensing by airborne lidar.

    PubMed

    Spinhirne, J D; Hansen, M Z; Caudill, L O

    1982-05-01

    Observations of cloud top height, backscattering, and signal depolarization have been obtained by a lidar system operating onboard a high-altitude research aircraft. The transmitter for the cloud lidar system is a doubled Nd:YAG laser operating at 5 Hz. The system functions as a fully automated sensor under microprocessor control and operates from a nominal 19-km altitude. Measurements have been acquired over a wide variety of cloud cover in conjunction with passive visible and infrared measurements. Initial observation results are reported.

  7. A method for the detection of the severe rain-on-snow event on Banks Island, October 2003, using passive microwave remote sensing

    NASA Astrophysics Data System (ADS)

    Grenfell, T. C.; Putkonen, J.

    2008-03-01

    Severe wintertime rain-on-snow (ROS) events create a strong ice layer (or layers) in the snow on arctic tundra that act as a barrier to ungulate grazing. They are linked with large-scale ungulate (reindeer, caribou, elk, and musk-ox) herd declines via starvation and reduced calf production rate when the animals are unable to penetrate the resulting subsnowpack ice layer. ROS events also produce considerable perturbation in the mean wintertime soil temperature under the snowpack. ROS is a sporadic but well-known and significant phenomenon that is currently very poorly documented. Characterization of the distribution and occurrence of severe ROS events is based only on anecdotal evidence, indirect observations of carcasses found adjacent to iced snowpacks, and irregular detection by a sparse observational weather network. We have analyzed in detail a particular ROS event that took place on Banks Island in early October 2003 that resulted in the death of 20,000 musk oxen. We make use of multifrequency passive microwave imagery from the Special Sensor Microwave Imager satellite sensor suite in conjunction with a strong-fluctuation-theory (SFT) emissivity model. We show that a combination of time series analysis and cluster analysis based on microwave spectral gradients and polarization ratios provides a means to detect the stages of the ROS event resulting from the modification of the vertical structure of the snowpack, specifically wetting the snow, the accumulation of liquid water at the base of the snow during the rain event, and the subsequent modification of the snowpack after refreezing. SFT model analysis provides quantitative confirmation of our interpretation of the evolution of the microwave properties of the snowpack as a result of the ROS event. In addition to the grain coarsening owing to destructive metamorphism, we detect the presence of the internal water and ice layers, directly identifying the physical properties producing the hazardous conditions

  8. Sandia Multispectral Airborne Lidar for UAV Deployment

    SciTech Connect

    Daniels, J.W.; Hargis,Jr. P.J.; Henson, T.D.; Jordan, J.D.; Lang, A.R.; Schmitt, R.L.

    1998-10-23

    Sandia National Laboratories has initiated the development of an airborne system for W laser remote sensing measurements. System applications include the detection of effluents associated with the proliferation of weapons of mass destruction and the detection of biological weapon aerosols. This paper discusses the status of the conceptual design development and plans for both the airborne payload (pointing and tracking, laser transmitter, and telescope receiver) and the Altus unmanned aerospace vehicle platform. Hardware design constraints necessary to maintain system weight, power, and volume limitations of the flight platform are identified.

  9. The National Airborne Field Experiment 2006 (NAFE'06) Dataset

    NASA Astrophysics Data System (ADS)

    Panciera, R.; Walker, J. P.; Merlin, O.; Kalma, J.; Kim, E.; Hacker, J.

    2007-05-01

    Remote sensing technology has a huge potential for improving hydrologic prediction through soil moisture measurement. This is particularly so given that the first dedicated soil moisture satellite, the Soil Moisture and Ocean Salinity (SMOS) mission, is to be launched in late 2007. However, targeted field experiments must be undertaken and the data analysed prior to launch so that immediate use can be made of this data when it becomes available. Consequently, the National Airborne Field Experiment was conducted in the Murrumbidge catchment, located in south-eastern Australia, during November 2006 (NAFE'06). The intent of this experiment was to provide simulated SMOS observations supported by ground measurement of soil moisture and other relevant ground data for i) development of the SMOS retrieval algorithms, ii) developing approaches for downscaling the low resolution data from SMOS to 1km resolution, and iii) testing its assimilation into land surface models for root zone soil moisture retrieval. This paper describes the NAFE'06 data set. The SMOS-type data were collected using a Polarimetric L-band Multi-beam Radiometer (PLMR), together with supporting instruments (thermal imager, tri-spectral scanner, lidar and digital photograph). Flights included 1km resolution passive microwave data across the main 40km x 55km Yanco study area every 2-3 days, for simulation of a SMOS pixel, verification of downscaling techniques and assimilation, and a transect across the area twice a week to provide both 500m multi-angular passive microwave data for SMOS algorithm development and 50m resolution passive microwave data for algorithm verification. This was done alternatively at 6am and 6pm, so that both SMOS overpass times could be tested. A medium resolution flight (250m for PLMR) was also performed once per week across an irrigated portion of the Yanco study area to study the effect of standing water on microwave emission. The NDVI, lidar and aerial photo supporting

  10. Downscaling of Airborne Wind Energy Systems

    NASA Astrophysics Data System (ADS)

    Fechner, Uwe; Schmehl, Roland

    2016-09-01

    Airborne wind energy systems provide a novel solution to harvest wind energy from altitudes that cannot be reached by wind turbines with a similar nominal generator power. The use of a lightweight but strong tether in place of an expensive tower provides an additional cost advantage, next to the higher capacity factor and much lower total mass. This paper investigates the scaling effects of airborne wind energy systems. The energy yield of airborne wind energy systems, that work in pumping mode of operation is at least ten times higher than the energy yield of conventional solar systems. For airborne wind energy systems the yield is defined per square meter wing area. In this paper the dependency of the energy yield on the nominal generator power for systems in the range of 1 kW to 1 MW is investigated. For the onshore location Cabauw, The Netherlands, it is shown, that a generator of just 1.4 kW nominal power and a total system mass of less than 30 kg has the theoretical potential to harvest energy at only twice the price per kWh of large scale airborne wind energy systems. This would make airborne wind energy systems a very attractive choice for small scale remote and mobile applications as soon as the remaining challenges for commercialization are solved.

  11. International Symposium on Remote Sensing of Environment, 21st, University of Michigan, Ann Arbor, Oct. 26-30, 1987, Proceedings. Volumes 1 and 2

    SciTech Connect

    Not Available

    1987-01-01

    Papers on remote sensors, data systems, and scientific investigations related to land, open ocean, ice, astmosphere, and climate research are presented. Topics include the High-Resolution Imaging Spectrometer for NASA's Earth Observing System; the future of remote sensing techniques; airborne electrooptical imaging; airborne stereo line imager data; a helicopter-borne scatterometer; SAR image data compression; international remote-sensing satellites; Radarsat; the integration of remote sensing and geographic information systems; the Argos system; TM data screening; surveillance radar; the use of microwave radiometry in hydrology; and the use of Landsat, AVHRR, and SPOT data in environmental studies. Research using remote-sensing techniques is presented, covering topics such as the measurement of currents, intense and tornadic thunderstorms, suspended sediments in estuaries, calculating land and forest cover, flash flood potential, sea-level variations, agricultural monitoring, fire detection, anaylsis of marine shallow water-bottom features, detection of human-induced environmental change, crop yield estimation, the composition of volcanic rocks, ice surveillance, snow-cover mapping, road detection, surface wind-speed measurements, and mineral exploration.

  12. Recent progresses in atmospheric remote sensing research in China —Chinese national report on atmospheric remote sensing research in China during 1999 2003

    NASA Astrophysics Data System (ADS)

    Qiu, Jinhuan; Chen, Hongbin

    2004-06-01

    Progresses of atmospheric remote sensing research in China during 1999 2003 are summarily introduced. This research includes: (1) microwave remote sensing of the atmosphere; (2) Lidar remote sensing; (3) remote sensing of aerosol optical properties; and (4) other research related to atmospheric remote sensing, including GPS remote sensing of precipitable water vapor and radiation model development.

  13. Bridging the Past with Today's Microwave Remote Sensing: A Case Study of Long Term Inundation Patterns in the Mekong River Delta

    NASA Astrophysics Data System (ADS)

    Jensen, K.; McDonald, K. C.; Schroeder, R.; Tessler, Z. D.

    2015-12-01

    Surface inundation extent and its predictability vary tremendously across the globe. This dynamic is being and has been captured by three general categories of satellite imagery: 1) low-spatial-resolution microwave sensors with global coverage and a long record of observations (e.g., SSM/I), 2) optical sensors with high spatial and temporal resolution and global coverage, but with cloud contamination (e.g. MODIS), and 3) in more ''snapshot'' form by high-resolution synthetic aperture radar (SAR) sensors. We explore the ability to bridge techniques that can exploit the higher spatial resolution of more recent data products back in time with the help of the temporal evolution of lower resolution products. We present a study of long term (20+ year) inundation patterns in the Mekong River Delta using baseline observations from the Surface Water Microwave Product Series (SWAMPS), an inundation area fraction product derived at 25km scale from active and passive microwave instruments (ERS, QuikSCAT, ASCAT, and SSM/I) that spans from Jan. 1992 to Jun. 2015. Every hydrological basin has unique characteristics - such as its topography, land cover / land use, and space-time variability - thus, a downscaling algorithm needs to take into account these idiosyncrasies. We merge SWAMPS with topographical information derived from 30m SRTM DEM, river networks from USGS HydroSHEDS, and assess the best statistical procedure to "learn" from two sets of classified SAR data: (1) L-band imaging radar from ALOS PALSAR, 2007-2010, and (2) C-band imagery from the Sentinel-1 mission (2014 to present). We present a comparison of retrospective downscaled flood extent with Landsat imagery and recent observations from SMAP. With a higher spatial resolution of past flooding extent, we can improve our understanding of how delta surface hydrology responds to local and regional events. This is important both in the short-term for accurate flood prediction, as well as on longer-term planning horizons.

  14. Airborne Research Experience for Educators

    NASA Astrophysics Data System (ADS)

    Costa, V. B.; Albertson, R.; Smith, S.; Stockman, S. A.

    2009-12-01

    The Airborne Research Experience for Educators (AREE) Program, conducted by the NASA Dryden Flight Research Center Office of Education in partnership with the AERO Institute, NASA Teaching From Space Program, and California State University Fullerton, is a complete end-to-end residential research experience in airborne remote sensing and atmospheric science. The 2009 program engaged ten secondary educators who specialize in science, technology, engineering or mathematics in a 6-week Student Airborne Research Program (SARP) offered through NSERC. Educators participated in collection of in-flight remote sensor data during flights aboard the NASA DC-8 as well as in-situ research on atmospheric chemistry (bovine emissions of methane); algal blooms (remote sensing to determine location and degree of blooms for further in-situ analysis); and crop classification (exploration of how drought conditions in Central California have impacted almond and cotton crops). AREE represents a unique model of the STEM teacher-as-researcher professional development experience because it asks educators to participate in a research experience and then translate their experiences into classroom practice through the design, implementation, and evaluation of instructional materials that emphasize the scientific research process, inquiry-based investigations, and manipulation of real data. Each AREE Master Educator drafted a Curriculum Brief, Teachers Guide, and accompanying resources for a topic in their teaching assignment Currently, most professional development programs offer either a research experience OR a curriculum development experience. The dual nature of the AREE model engaged educators in both experiences. Educators’ content and pedagogical knowledge of STEM was increased through the review of pertinent research articles during the first week, attendance at lectures and workshops during the second week, and participation in the airborne and in-situ research studies, data

  15. Microwave Ovens

    MedlinePlus

    ... Required Reports for the Microwave Oven Manufacturers or Industry Exemption from Certain Reporting and Recordkeeping Requirements for ... Microwave Ovens (PDF) (PDF - 2.5MB) FDA eSubmitter Industry Guidance - Documents of Interest Notifications to Industry (PDF ...

  16. Summary of the active microwave users workshop

    NASA Technical Reports Server (NTRS)

    1978-01-01

    A coordinated microwave applications development program was initiated to improve the capability to: (1) identify, monitor, and assess the earth's resources; and (2) monitor the earth's environment and predict significant changes. The program consists of the scientific, technical, and programmatic activities required to develop microwave remote sensing into an operational tool for systematic earth observations.

  17. Analysis of Airborne Radar Altimetry Measurements of the Greenland Ice Sheet

    NASA Technical Reports Server (NTRS)

    Ferraro, Ellen J.

    1994-01-01

    This dissertation presents an analysis of airborne altimetry measurements taken over the Greenland ice sheet with the 13.9 GHz Advanced Application Flight Experiment (AAFE) pulse compression radar altimeter. This Ku-band instrument was refurbished in 1990 by the Microwave Remote Sensing Laboratory at the University of Massachusetts to obtain high-resolution altitude measurements and to improve the tracking, speed, storage and display capabilities of the radar. In 1991 and 1993, the AAFE altimeter took part in the NASA Multisensor Airborne Altimetry Experiments over Greenland, along with two NASA laser altimeters. Altitude results from both experiments are presented along with comparisons to the laser altimeter and calibration passes over the Sondrestroem runway in Greenland. Although it is too early to make a conclusion about the growth or decay of the ice sheet, these results show that the instrument is capable of measuring small-scale surface changes to within 14 centimeters. In addition, results from these experiments reveal that the radar is sensitive to the different diagenetic regions of the ice sheet. Return waveforms from the wet- snow, percolation and dry-snow zones show varying effects of both surface scattering and sub-surface or volume scattering. Models of each of the diagenetic regions of Greenland are presented along with parameters such as rms surface roughness, rms surface slope and attenuation coefficient of the snow pack obtained by fitting the models to actual return waveforms.

  18. Airborne laser sensors and integrated systems

    NASA Astrophysics Data System (ADS)

    Sabatini, Roberto; Richardson, Mark A.; Gardi, Alessandro; Ramasamy, Subramanian

    2015-11-01

    The underlying principles and technologies enabling the design and operation of airborne laser sensors are introduced and a detailed review of state-of-the-art avionic systems for civil and military applications is presented. Airborne lasers including Light Detection and Ranging (LIDAR), Laser Range Finders (LRF), and Laser Weapon Systems (LWS) are extensively used today and new promising technologies are being explored. Most laser systems are active devices that operate in a manner very similar to microwave radars but at much higher frequencies (e.g., LIDAR and LRF). Other devices (e.g., laser target designators and beam-riders) are used to precisely direct Laser Guided Weapons (LGW) against ground targets. The integration of both functions is often encountered in modern military avionics navigation-attack systems. The beneficial effects of airborne lasers including the use of smaller components and remarkable angular resolution have resulted in a host of manned and unmanned aircraft applications. On the other hand, laser sensors performance are much more sensitive to the vagaries of the atmosphere and are thus generally restricted to shorter ranges than microwave systems. Hence it is of paramount importance to analyse the performance of laser sensors and systems in various weather and environmental conditions. Additionally, it is important to define airborne laser safety criteria, since several systems currently in service operate in the near infrared with considerable risk for the naked human eye. Therefore, appropriate methods for predicting and evaluating the performance of infrared laser sensors/systems are presented, taking into account laser safety issues. For aircraft experimental activities with laser systems, it is essential to define test requirements taking into account the specific conditions for operational employment of the systems in the intended scenarios and to verify the performance in realistic environments at the test ranges. To support the

  19. Detection and Monitoring of Stratigraphic Markers and Temperature Trends at the Greenland Ice Sheet Project 2 Using Passive-Microwave Remote-Sensing Data

    NASA Technical Reports Server (NTRS)

    Shuman, C. A.; Alley, R. B.; Fahnestock, M. A.; Fawcett, P. J.; Bondschadler, R. A.; White, J. W. C.; Grootes, P. M.; Anandakrishnan, S.; Stearns, C. R.

    1997-01-01

    Satellite passive-microwave sensors provide a sensitive means of studying ice-sheet surface processes that assists ice-core interpretation and can extend local observations across regional scales. Analysis of special sensor microwave/imager (SSM/I) brightness temperature (TB) data supports ice-core research in two specific ways. First, the summer hoar complex layers used to date the Holocene portion of the Greenland Ice Sheet Project 2 ice core can be defined temporally and spatially by SSM/I 37-GHz vertically (V) and horizontally (H) polarized B ratio (V/H) trends. Second, comparison of automatic weather station temperatures to SSM/I 37-GHz V TB data shows that they are an effective proxy temperature record in this region. Also, the TB data can be correlated with proxy temperature trends from stable-isotope-ratio (delta O-18 and delta-D) profiles from snow pits and this allows the assignment of dates to specific snow depths.

  20. Estimation of the infiltration loss volume from the reservoir cooler of the Chernobyl power plant to the Pripyat river using remote sensing research in the microwave and IR ranges

    NASA Astrophysics Data System (ADS)

    Lyalko, Vadim I.; Vulfson, Leonid D.; Shevchenko, Victor N.; Filippov, Yuri V.; Kobets, Nickolay I.

    1997-12-01

    The research problem is to reveal location and estimate total intensity of the filtration flows, that pass under the dam body from the reservoir-cooler and unload to the Pripyat River. With this aim the CARTE airborne-laboratory has provided remote sensing survey of the radiation temperature fields on the ground surface, the soil surface layer moisture and the underground water level depth. As a result of the survey data processing the zones of the wet soil with underground water level higher than ground surface level have been located. Within these zones the low value of Trad was observed. The value of Trad was determined on day time by increased heat debit on evaporation and large thermal inertia of the wet soil, retarding its heat by insulation. Such coincidence of positive W anomalies and negative Trad anomalies made possible to draw conclusion that they were confined to the areas of the underground water unloading from the reservoir-cooler under the dam to the Pripyat River. By resulted data the estimation of the filtration loss value under the dam has been performed.

  1. DARLA: Data Assimilation and Remote Sensing for Littoral Applications

    NASA Astrophysics Data System (ADS)

    Jessup, A.; Holman, R. A.; Chickadel, C.; Elgar, S.; Farquharson, G.; Haller, M. C.; Kurapov, A. L.; Özkan-Haller, H. T.; Raubenheimer, B.; Thomson, J. M.

    2012-12-01

    DARLA is 5-year collaborative project that couples state-of-the-art remote sensing and in situ measurements with advanced data assimilation (DA) modeling to (a) evaluate and improve remote sensing retrieval algorithms for environmental parameters, (b) determine the extent to which remote sensing data can be used in place of in situ data in models, and (c) infer bathymetry for littoral environments by combining remotely-sensed parameters and data assimilation models. The project uses microwave, electro-optical, and infrared techniques to characterize the littoral ocean with a focus on wave and current parameters required for DA modeling. In conjunction with the RIVET (River and Inlets) Project, extensive in situ measurements provide ground truth for both the remote sensing retrieval algorithms and the DA modeling. Our goal is to use remote sensing to constrain data assimilation models of wave and circulation dynamics in a tidal inlet and surrounding beaches. We seek to improve environmental parameter estimation via remote sensing fusion, determine the success of using remote sensing data to drive DA models, and produce a dynamically consistent representation of the wave, circulation, and bathymetry fields in complex environments. The objectives are to test the following three hypotheses: 1. Environmental parameter estimation using remote sensing techniques can be significantly improved by fusion of multiple sensor products. 2. Data assimilation models can be adequately constrained (i.e., forced or guided) with environmental parameters derived from remote sensing measurements. 3. Bathymetry on open beaches, river mouths, and at tidal inlets can be inferred from a combination of remotely-sensed parameters and data assimilation models. Our approach is to conduct a series of field experiments combining remote sensing and in situ measurements to investigate signature physics and to gather data for developing and testing DA models. A preliminary experiment conducted at

  2. A Melting-Layer Model for Passive/Active Microwave Remote Sensing Applications. Part I: Model Formulation and Comparison with Observations.

    NASA Astrophysics Data System (ADS)

    Olson, William S.; Bauer, Peter; Viltard, Nicolas F.; Johnson, Daniel E.; Tao, Wei-Kuo; Meneghini, Robert; Liao, Liang

    2001-07-01

    In this study, a 1D steady-state microphysical model that describes the vertical distribution of melting precipitation particles is developed. The model is driven by the ice-phase precipitation distributions just above the freezing level at applicable grid points of `parent' 3D cloud-resolving model (CRM) simulations. It extends these simulations by providing the number density and meltwater fraction of each particle in finely separated size categories through the melting layer. The depth of the modeled melting layer is primarily determined by the initial material density of the ice-phase precipitation. The radiative properties of melting precipitation at microwave frequencies are calculated based upon different methods for describing the dielectric properties of mixed-phase particles. Particle absorption and scattering efficiencies at the Tropical Rainfall Measuring Mission Microwave Imager frequencies (10.65-85.5 GHz) are enhanced greatly for relatively small (0.1) meltwater fractions. The relatively large number of partially melted particles just below the freezing level in stratiform regions leads to significant microwave absorption, well exceeding the absorption by rain at the base of the melting layer. Calculated precipitation backscatter efficiencies at the precipitation radar frequency (13.8 GHz) increase with particle meltwater fraction, leading to a `bright band' of enhanced radar reflectivities in agreement with previous studies. The radiative properties of the melting layer are determined by the choice of dielectric models and the initial water contents and material densities of the `seeding' ice-phase precipitation particles. Simulated melting-layer profiles based upon snow described by the Fabry-Szyrmer core-shell dielectric model and graupel described by the Maxwell-Garnett water matrix dielectric model lead to reasonable agreement with radar-derived melting-layer optical depth distributions. Moreover, control profiles that do not contain mixed

  3. Improvements and Extension to a Global Earth System Data Record of Daily Landscape Freeze-Thaw Status Determined from Satellite Microwave Remote Sensing

    NASA Astrophysics Data System (ADS)

    Kim, Y.; Kimball, J. S.; Du, J.; Glassy, J. M.

    2014-12-01

    A global satellite microwave Earth System Data Record of daily landscape freeze-thaw status (FT-ESDR) has been commonly used to quantify cold temperature impacts on productivity, phenology, evapotranspiration and the terrestrial carbon cycle. Overlapping 37 GHz, vertically polarized brightness temperature (Tb) measurements from the Scanning Multichannel Microwave Radiometer (SMMR) and Special Sensor Microwave Imager (SSM/I) were integrated to produce a temporally consistent and continuous global daily FT data record from 1979 to 2012 and derived at 25-km pixel resolution. In this study, we develop and evaluate FT-ESDR enhancements, including expanded record length and spatial coverage, alternate algorithm calibrations, and a finer scale FT classification. A larger global domain is evaluated that encompasses all land areas affected by seasonally frozen temperatures, including urban, snow-ice dominant, barren, and permafrost landscapes. The FT retrieval is obtained using a seasonal threshold algorithm (STA) that classifies daily Tb changes in relation to frozen and non-frozen Tb reference states on a per-pixel basis. STA sensitivity to FT reference states is evaluated and alternative ancillary data are applied for defining Tb reference conditions, including surface temperatures from global reanalysis and MODIS land surface temperature (LST) seasonal climatology. The resulting FT record shows mean annual spatial classification accuracies of 92 and 86 percent for PM and AM overpass retrievals relative to in-situ temperature measurements. Despite the larger domain and longer record, the new FT-ESDR showed a 1-3 percent spatial classification accuracy improvement over previous FT-ESDR versions. Areas with enhanced accuracy include the Central USA, Central Asia, and North and Central Europe. Sub-grid land surface spatial heterogeneity effects on the aggregate FT retrievals are also assessed to refine FT-ESDR data quality metrics. The results of this study are being

  4. [Multi-Scale Convergence of Cold-Land Process Representation in Land-Surface Models, Microwave Remote Sensing, and Field Observations

    NASA Technical Reports Server (NTRS)

    Shi, Jiancheng

    2005-01-01

    The cryosphere is a major component of the hydrosphere and interacts significantly with the global climate system, the geosphere, and the biosphere. Measurement of the amount of water stored in the snow pack and forecasting the rate of melt are thus essential for managing water supply and flood control systems. Snow hydrologists are confronted with the dual problems of estimating both the quantity of water held by seasonal snow packs and time of snow melt. Monitoring these snow parameters is essential for one of the objectives of the Earth Science Enterprise-understanding of the global hydrologic cycle. Measuring spatially distributed snow properties, such as snow water equivalence (SWE) and wetness, from space is a key component for improvement of our understanding of coupled atmosphere-surface processes. Through the GWEC project, we have significantly advanced our understandings and improved modeling capabilities of the microwave signatures in response to snow and underground properties.

  5. Developments in Airborne Oceanography and Air-Sea Interaction

    NASA Astrophysics Data System (ADS)

    Melville, W. K.

    2014-12-01

    One of the earliest ocean-related flights was that of Amundsen to be first across the North Pole and Arctic from Svalbard to Alaska in the airship Norge in 1926. Twenty five years later Cox & Munk flew a B-17G "Flying Fortress" bomber over Hawaiian waters measuring sea surface slope statistics from photographs of sun glitter and wind speed from a yacht. The value of Cox & Munk's "airborne oceanography" became apparent another twenty five years later with the short-lived Seasat microwave remote-sensing mission, since interpretation of the Seasat data in geophysical variables required scattering theories that relied on their data. The universal acceptance of remote sensing in oceanography began in 1992 with the launch of, and successful analysis of sea surface height data from, the Topex/Poseidon radar altimeter. With that and the development of more realistic coupled atmosphere-ocean models it became apparent that our understanding of weather and climate variability in both the atmosphere and the ocean depends crucially on our ability to measure processes in boundary layers spanning the interface. Ten years ago UNOLS formed the Scientific Committee for Oceanographic Aircraft Research (SCOAR) "...to improve access to research aircraft facilities for ocean sciences"; an attempt to make access to aircraft as easy as access to research vessels. SCOAR emphasized then that "Aircraft are ideal for both fast-response investigations and routine, long-term measurements, and they naturally combine atmospheric measurements with oceanographic measurements on similar temporal and spatial scales." Since then developments in GPS positioning and miniaturization have made scientific measurements possible from smaller and smaller platforms, including the transition from manned to unmanned aerial vehicles (UAVs). Furthermore, ship-launched and recovered UAVs have demonstrated how they can enhance the capabilities and reach of the research vessels, "projecting" research and science

  6. Flight results for the airborne Raman lidar

    NASA Technical Reports Server (NTRS)

    Heaps, William S.; Burris, John F.

    1995-01-01

    The airborne Raman lidar recently completed a series of flight tests aboard a C-130 aircraft operated by the NASA Wallops Flight Facility. The Raman lidar is intended to make simultaneous remote measurements of methane, water vapor, temperature, and pressure. The principal purpose of the measurements is to aid in the investigation of polar phenomena related to the formation of ozone 'holes' by permitting the identification of the origin of air parcels using methane as a tracer.

  7. ADVANCED REMOTE SENSING MONITORING OF MINE WASTE

    EPA Science Inventory

    The OEI-EAD and NERL-ESD have been cooperating on development of monitoring technologies and research to better use remote sensor-derived information and to ultimately disseminate that information to users. This work has focused on NASA'S airborne advanced remote sensor systems ...

  8. NASA'S Coastal and Ocean Airborne Science Testbed (COAST): Early Results

    NASA Astrophysics Data System (ADS)

    Guild, L. S.; Dungan, J. L.; Edwards, M.; Russell, P. B.; Morrow, J. H.; Kudela, R. M.; Myers, J. S.; Livingston, J.; Lobitz, B.; Torres-Perez, J.

    2012-12-01

    The NASA Coastal and Ocean Airborne Science Testbed (COAST) project advances coastal ecosystems research and ocean color calibration and validation capability by providing a unique airborne payload optimized for remote sensing in the optically complex coastal zone. The COAST instrument suite combines a customized imaging spectrometer, sunphotometer system, and a new bio-optical radiometer package to obtain ocean/coastal/atmosphere data simultaneously in flight for the first time. The imaging spectrometer (Headwall) is optimized in the blue region of the spectrum to emphasize remote sensing of marine and freshwater ecosystems. Simultaneous measurements supporting empirical atmospheric correction of image data is accomplished using the Ames Airborne Tracking Sunphotometer (AATS-14). Coastal Airborne In situ Radiometers (C-AIR, Biospherical Instruments, Inc.), developed for COAST for airborne campaigns from field-deployed microradiometer instrumentation, will provide measurements of apparent optical properties at the land/ocean boundary including optically shallow aquatic ecosystems. Ship-based measurements allowed validation of airborne measurements. Radiative transfer modeling on in-water measurements from the HyperPro and Compact-Optical Profiling System (C-OPS, the in-water companion to C-AIR) profiling systems allows for comparison of airborne and in-situ water leaving radiance measurements. Results of the October 2011 Monterey Bay COAST mission include preliminary data on coastal ocean color products, coincident spatial and temporal data on aerosol optical depth and water vapor column content, as well as derived exact water-leaving radiances.

  9. Compact Microwave Fourier Spectrum Analyzer

    NASA Technical Reports Server (NTRS)

    Savchenkov, Anatoliy; Matsko, Andrey; Strekalov, Dmitry

    2009-01-01

    A compact photonic microwave Fourier spectrum analyzer [a Fourier-transform microwave spectrometer, (FTMWS)] with no moving parts has been proposed for use in remote sensing of weak, natural microwave emissions from the surfaces and atmospheres of planets to enable remote analysis and determination of chemical composition and abundances of critical molecular constituents in space. The instrument is based on a Bessel beam (light modes with non-zero angular momenta) fiber-optic elements. It features low power consumption, low mass, and high resolution, without a need for any cryogenics, beyond what is achievable by the current state-of-the-art in space instruments. The instrument can also be used in a wide-band scatterometer mode in active radar systems.

  10. Deriving stratospheric trace gases from balloon-borne infrared/microwave limb sounding measurements

    NASA Astrophysics Data System (ADS)

    Xu, Jian; Schreier, Franz; Doicu, Adrian; Vogt, Peter; Trautmann, Thomas

    2013-05-01

    Infrared (IR)/microwave limb sounding is a well-established technique for remote sensing of the Earth's atmosphere. The developments in IR/microwave limb sounding have triggered the demand for adequate and reliable analysis models and methods.

  11. Visualizing Airborne and Satellite Imagery

    NASA Technical Reports Server (NTRS)

    Bierwirth, Victoria A.

    2011-01-01

    Remote sensing is a process able to provide information about Earth to better understand Earth's processes and assist in monitoring Earth's resources. The Cloud Absorption Radiometer (CAR) is one remote sensing instrument dedicated to the cause of collecting data on anthropogenic influences on Earth as well as assisting scientists in understanding land-surface and atmospheric interactions. Landsat is a satellite program dedicated to collecting repetitive coverage of the continental Earth surfaces in seven regions of the electromagnetic spectrum. Combining these two aircraft and satellite remote sensing instruments will provide a detailed and comprehensive data collection able to provide influential information and improve predictions of changes in the future. This project acquired, interpreted, and created composite images from satellite data acquired from Landsat 4-5 Thematic Mapper (TM) and Landsat 7 Enhanced Thematic Mapper plus (ETM+). Landsat images were processed for areas covered by CAR during the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCT AS), Cloud and Land Surface Interaction Campaign (CLASIC), Intercontinental Chemical Transport Experiment-Phase B (INTEXB), and Southern African Regional Science Initiative (SAFARI) 2000 missions. The acquisition of Landsat data will provide supplemental information to assist in visualizing and interpreting airborne and satellite imagery.

  12. Investigation of fugitive emissions from petrochemical transport barges using optical remote sensing

    EPA Science Inventory

    Recent airborne remote sensing survey data acquired with passive gas imaging equipment (PGIE), in this case infrared cameras, have shown potentially significant fugitive volatile organic carbon (VOC) emissions from petrochemical transport barges. The experiment found remote sens...

  13. Remote Sensing and Reflectance Profiling in Entomology.

    PubMed

    Nansen, Christian; Elliott, Norman

    2016-01-01

    Remote sensing describes the characterization of the status of objects and/or the classification of their identity based on a combination of spectral features extracted from reflectance or transmission profiles of radiometric energy. Remote sensing can be benchtop based, and therefore acquired at a high spatial resolution, or airborne at lower spatial resolution to cover large areas. Despite important challenges, airborne remote sensing technologies will undoubtedly be of major importance in optimized management of agricultural systems in the twenty-first century. Benchtop remote sensing applications are becoming important in insect systematics and in phenomics studies of insect behavior and physiology. This review highlights how remote sensing influences entomological research by enabling scientists to nondestructively monitor how individual insects respond to treatments and ambient conditions. Furthermore, novel remote sensing technologies are creating intriguing interdisciplinary bridges between entomology and disciplines such as informatics and electrical engineering.

  14. Remote Sensing and Reflectance Profiling in Entomology.

    PubMed

    Nansen, Christian; Elliott, Norman

    2016-01-01

    Remote sensing describes the characterization of the status of objects and/or the classification of their identity based on a combination of spectral features extracted from reflectance or transmission profiles of radiometric energy. Remote sensing can be benchtop based, and therefore acquired at a high spatial resolution, or airborne at lower spatial resolution to cover large areas. Despite important challenges, airborne remote sensing technologies will undoubtedly be of major importance in optimized management of agricultural systems in the twenty-first century. Benchtop remote sensing applications are becoming important in insect systematics and in phenomics studies of insect behavior and physiology. This review highlights how remote sensing influences entomological research by enabling scientists to nondestructively monitor how individual insects respond to treatments and ambient conditions. Furthermore, novel remote sensing technologies are creating intriguing interdisciplinary bridges between entomology and disciplines such as informatics and electrical engineering. PMID:26982438

  15. On the Fast Evaluation Method of Temperature and Gas Mixing Ratio Weighting Functions for Remote Sensing of Planetary Atmospheres in Thermal IR and Microwave

    NASA Technical Reports Server (NTRS)

    Ustinov, E. A.

    1999-01-01

    Evaluation of weighting functions in the atmospheric remote sensing is usually the most computer-intensive part of the inversion algorithms. We present an analytic approach to computations of temperature and mixing ratio weighting functions that is based on our previous results but the resulting expressions use the intermediate variables that are generated in computations of observable radiances themselves. Upwelling radiances at the given level in the atmosphere and atmospheric transmittances from space to the given level are combined with local values of the total absorption coefficient and its components due to absorption of atmospheric constituents under study. This makes it possible to evaluate the temperature and mixing ratio weighting functions in parallel with evaluation of radiances. This substantially decreases the computer time required for evaluation of weighting functions. Implications for the nadir and limb viewing geometries are discussed.

  16. Satellite Remote Sensing of Net Ecosystem CO2 Exchange Using Optical-IR and Microwave Sensors: Algorithm Development for the SMAP Decadal Survey Mission

    NASA Astrophysics Data System (ADS)

    Jones, L. A.; Kimball, J. S.; Reichle, R. H.; Zhang, K.; McDonald, K. C.

    2009-12-01

    The global balance between photosynthesis, respiration, and disturbance determines whether ecosystems will continue to offset human CO2 emissions. Changes in temperature and moisture constraints can differentially affect photosynthesis and respiration, whereas disturbance and stand succession can push ecosystems far from steady state, shifting carbon source-sink dynamics. Remote sensing and ecosystem process model simulations allow us to characterize the climatic sensitivity of this balance, but effective model parameters are uncertain at continental scales. We developed a carbon model to derive daily net ecosystem exchange of CO2 (NEE) using MODIS GPP and surface soil moisture and temperature retrievals from AMSR-E as driving data. We apply Bayesian synthesis to parameterize the model with a range of FLUXNET tower CO2 measurements across representative global biomes, while accounting for error in flux observations, driving data, and model structure. Model fit diagnostics are compared to determine the relative value of remotely sensed information for accurate prediction of carbon fluxes. Model parameters vary with ecosystem type and indicate that most ecosystems have not reached soil organic carbon pools expected for steady state. Model fit is relatively more impacted by MODIS GPP than by AMSR-E temperature and moisture. AMSR-E moisture explains arid region fluxes, whereas temperature is a stronger predictor for high-latitude locations. The results of this study offer a benchmark for calibrating and assessing the incremental value of Soil Moisture Active Passive (SMAP) mission observations over information available from existing sensors. The Soil Moisture Active Passive (SMAP) mission with scheduled 2013 launch date will provide moderate resolution soil moisture (10 km) and freeze-thaw state (1-3 km) information potentially providing new estimates of land surface processes, including daily NEE. This work was performed at The University of Montana and Jet

  17. Microwave detector

    DOEpatents

    Meldner, Heiner W.; Cusson, Ronald Y.; Johnson, Ray M.

    1986-01-01

    A microwave detector (10) is provided for measuring the envelope shape of a microwave pulse comprised of high-frequency oscillations. A biased ferrite (26, 28) produces a magnetization field flux that links a B-dot loop (16, 20). The magnetic field of the microwave pulse participates in the formation of the magnetization field flux. High-frequency insensitive means (18, 22) are provided for measuring electric voltage or current induced in the B-dot loop. The recorded output of the detector is proportional to the time derivative of the square of the envelope shape of the microwave pulse.

  18. Microwave detector

    DOEpatents

    Meldner, H.W.; Cusson, R.Y.; Johnson, R.M.

    1985-02-08

    A microwave detector is provided for measuring the envelope shape of a microwave pulse comprised of high-frequency oscillations. A biased ferrite produces a magnetization field flux that links a B-dot loop. The magnetic field of the microwave pulse participates in the formation of the magnetization field flux. High-frequency insensitive means are provided for measuring electric voltage or current induced in the B-dot loop. The recorded output of the detector is proportional to the time derivative of the square of the envelope shape of the microwave pulse.

  19. Predicting risk of invasive species occurrence - remote-sesning strategies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Remote sensing is a means to describe characteristics of an area without physically sampling the area. Remote sensors can be mounted on a satellite, plane, or other airborne structure. Remotely sensed data allow for landscape perspectives on management issues. Sensors measure the electromagnetic ene...