The Experts below are selected from a list of 327 Experts worldwide ranked by ideXlab platform
M. Kuester - One of the best experts on this subject based on the ideXlab platform.
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IGARSS - Transformation of Solar Disc Radiances into a Top of the Atmosphere Radiance Source for On-Orbit Solar Calibration of Terrestrial Radiance Measurements
2006 IEEE International Symposium on Geoscience and Remote Sensing, 2006Co-Authors: D. Heath, A. Slaymaker, M. KuesterAbstract:Characteristics have been measured for a series of transmission optical devices that are considered for use in transforming solar disc Radiances into a top of the atmosphere solar Radiance source which can be used to calibrate terrestrial Radiance measurements derived from orbiting remote sensing instruments. The types of transmission optical elements that were evaluated are a diffraction hole-plate, plates of fused silica and glass with ground surfaces, several types of microlens arrays and "engineered" diffusers. Collimated light from a diffuse source with approximately the angular solar diameter was imaged onto a CCD camera by a long focal length achromat at multiple narrow band wavelengths. The optical transform device was inserted into the beam of collimated radiation on the source side of the achromatic lens.
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Transformation of Solar Disc Radiances into a Top of the Atmosphere Radiance Source for On-Orbit Solar Calibration of Terrestrial Radiance Measurements
2006 IEEE International Symposium on Geoscience and Remote Sensing, 2006Co-Authors: D. Heath, A. Slaymaker, M. KuesterAbstract:Characteristics have been measured for a series of transmission optical devices that are considered for use in transforming solar disc Radiances into a top of the atmosphere solar Radiance source which can be used to calibrate terrestrial Radiance measurements derived from orbiting remote sensing instruments. The types of transmission optical elements that were evaluated are a diffraction hole-plate, plates of fused silica and glass with ground surfaces, several types of microlens arrays and "engineered" diffusers. Collimated light from a diffuse source with approximately the angular solar diameter was imaged onto a CCD camera by a long focal length achromat at multiple narrow band wavelengths. The optical transform device was inserted into the beam of collimated radiation on the source side of the achromatic lens.
S.g. Schladow - One of the best experts on this subject based on the ideXlab platform.
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In-flight validation of mid- and thermal infrared data from the Multispectral Thermal Imager (MTI) using an automated high-altitude validation site at Lake Tahoe CA/NV, USA
IEEE Transactions on Geoscience and Remote Sensing, 2005Co-Authors: S.j. Hook, W.b. Clodius, L. Balick, R.e. Alley, A. Abtahi, R.c. Richards, S.g. SchladowAbstract:The Multispectral Thermal Imager (MTI) is a 15-band satellite-based imaging system. Two of the bands (J, K) are located in the mid-infrared (3-5 /spl mu/m) wavelength region: J, 3.5-4.1 /spl mu/m and K, 4.9-5.1 /spl mu/m, and three of the bands (L, M, N) are located in the thermal infrared (8-12 /spl mu/m) wavelength region: L, 8.0-8.4 /spl mu/m; M, 8.4-8.8 /spl mu/m; and N, 10.2-10.7 /spl mu/m. The absolute radiometric accuracy of the MTI data acquired in bands J-N was assessed over a period of approximately three years using data from the Lake Tahoe, CA/NV, automated validation site. Assessment involved using a radiative transfer model to propagate surface skin temperature measurements made at the time of the MTI overpass to predict the vicarious at-sensor Radiance. The vicarious at-sensor Radiance was convolved with the MTI system response functions to obtain the vicarious at-sensor MTI Radiance in bands J-N. The vicarious Radiances were then compared with the instrument measured Radiances. In order to avoid any reflected solar contribution in the mid-infrared bands, only nighttime scenes were used in the analysis of bands J and K. Twelve cloud-free scenes were used in the analysis of the data from the mid-infrared bands (J, K), and 23 cloud-free scenes were used in the analysis of the thermal infrared bands (L, M, N). The scenes had skin temperatures ranging between 4.4 and 18.6/spl deg/C. The skin temperature was found to be, on average, 0.18/spl plusmn/0.36 degC cooler than the bulk temperature during the day and 0.65/spl plusmn/0.31 degC cooler than the bulk temperature at night. The smaller skin effect during the day was attributed to solar heating. The mean and standard deviation of the percent differences between the vicarious (predicted) at-sensor Radiance convolved to the MTI bandpasses and the MTI measured Radiances were -1.38/spl plusmn/2.32, -2.46/spl plusmn/1.96, -0.04/spl plusmn/0.78, -1.97/spl plusmn/0.62, -1.59/spl plusmn/0.55 for bands J-N, respectively. The results indicate that, with the exception of band L, the instrument measured Radiances are warmer than expected.
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in flight validation and recovery of water surface temperature with landsat 5 thermal infrared data using an automated high altitude lake validation site at lake tahoe
IEEE Transactions on Geoscience and Remote Sensing, 2004Co-Authors: Simon J Hook, Frank D. Palluconi, A. Abtahi, R.c. Richards, S.g. Schladow, Gyanesh Chander, Julia A Barsi, Ronald E Alley, Brian L Markham, Dennis L HelderAbstract:The absolute radiometric accuracy of the thermal infrared band (B6) of the Thematic Mapper (TM) instrument on the Landsat-5 (L5) satellite was assessed over a period of approximately four years using data from the Lake Tahoe automated validation site (California-Nevada). The Lake Tahoe site was established in July 1999, and measurements of the skin and bulk temperature have been made approximately every 2 min from four permanently moored buoys since mid-1999. Assessment involved using a radiative transfer model to propagate surface skin temperature measurements made at the time of the L5 overpass to predict the at-sensor Radiance. The predicted Radiance was then convolved with the L5B6 system response function to obtain the predicted L5B6 Radiance, which was then compared with the Radiance measured by L5B6. Twenty-four cloud-free scenes acquired between 1999 and 2003 were used in the analysis with scene temperatures ranging between 4/spl deg/C and 22/spl deg/C. The results indicate L5B6 had a Radiance bias of 2.5% (1.6/spl deg/C) in late 1999, which gradually decreased to 0.8% (0.5/spl deg/C) in mid-2002. Since that time, the bias has remained positive (predicted minus measured) and between 0.3% (0.2/spl deg/C) and 1.4% (0.9/spl deg/C). The cause for the cold bias (L5 Radiances are lower than expected) is unresolved, but likely related to changes in instrument temperature associated with changes in instrument usage. The in situ data were then used to develop algorithms to recover the skin and bulk temperature of the water by regressing the L5B6 Radiance and the National Center for Environmental Prediction (NCEP) total column water data to either the skin or bulk temperature. Use of the NCEP data provides an alternative approach to the split-window approach used with instruments that have two thermal infrared bands. The results indicate the surface skin and bulk temperature can be recovered with a standard error of 0.6/spl deg/C. This error is larger than errors obtained with other instruments due, in part, to the calibration bias. L5 provides the only long-duration high spatial resolution thermal infrared measurements of the land surface. If these data are to be used effectively in studies designed to monitor change, it is essential to continue to monitor instrument performance in-flight and develop quantitative algorithms for recovering surface temperature.
Hideyuki Tonooka - One of the best experts on this subject based on the ideXlab platform.
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Vicarious calibration of ASTER thermal infrared bands
IEEE Transactions on Geoscience and Remote Sensing, 2005Co-Authors: Hideyuki Tonooka, Frank D. Palluconi, Simon J Hook, Tsuneo MatsunagaAbstract:The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on the, Terra satellite has five bands in the thermal infrared (TIR) spectral region between 8-12 mu m. The TIR bands have been regularly validated in-flight using ground validation targets., Validation results are presented from 79 experiments conducted under clear sky conditions. Validation involved predicting the at-sensor Radiance for each band using a radiative transfer model, driven by surface and atmospheric measurements from each experiment, and then comparing the predicted Radiance with the ASTER measured Radiance. The results indicate the average difference between the predicted and the ASTER measured Radiances was no more than 0.5% or 0.4 K in any TIR band, demonstrating that the TIR bands have exceeded the preflight design accuracy of < 1 K for an at-sensor brightness temperature range of 270-340 K. The predicted and the ASTER measured Radiances were then used to assess how well the onboard calibration accounted for any changes in both the instrument gain and offset over time. The results indicate that the gain and offset were correctly determined using the onboard blackbody, and indicate a responsivity decline over the first 1400 days of the Terra mission.
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Inflight straylight analysis for ASTER thermal infrared bands
IEEE Transactions on Geoscience and Remote Sensing, 2005Co-Authors: Hideyuki TonookaAbstract:The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument was launched into Earth orbit on the Terra platform in late 1999. ASTER produces images of the Earth in 14 spectral bands including five bands in the thermal infrared (TIR) part of the electromagnetic spectrum (8-12 /spl mu/m). On one occasion ASTER was used to image the Moon as part of the long-term calibration strategy for instruments on the Terra platform. Analysis of the imagery revealed that the TIR band had noticeable straylight effects (ghosting), and an algorithm was developed to correct for these effects. The algorithm was applied to ASTER/TIR images acquired over a vicarious calibration (VC) site at Cold Springs Reservoir (CSR), NV. Data from CSR had been evaluated in three previous VC experiments and showed large unexplained differences between the ASTER image Radiance and vicarious predicted Radiance not observed in other larger, more laterally homogenous sites. After straylight correction the vicarious and image Radiances were in good agreement. A further comparison with nearly simultaneous airborne TIR data acquired with the MODIS/ASTER (MASTER) sensor indicated that the ASTER straylight corrected data also agreed with the airborne data. Finally, the algorithm was applied to artificially created models. The results indicated that a Radiance change caused by straylight reached 6% to 8% of a Radiance contrast for a smaller square target than 10/spl times/10 pixels or a narrower line target than five pixels. Straylight in ASTER/TIR imagery may not be very large for most targets, but may become an error factor for high-Radiance-contrast targets.
Simon J Hook - One of the best experts on this subject based on the ideXlab platform.
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Vicarious calibration of ASTER thermal infrared bands
IEEE Transactions on Geoscience and Remote Sensing, 2005Co-Authors: Hideyuki Tonooka, Frank D. Palluconi, Simon J Hook, Tsuneo MatsunagaAbstract:The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on the, Terra satellite has five bands in the thermal infrared (TIR) spectral region between 8-12 mu m. The TIR bands have been regularly validated in-flight using ground validation targets., Validation results are presented from 79 experiments conducted under clear sky conditions. Validation involved predicting the at-sensor Radiance for each band using a radiative transfer model, driven by surface and atmospheric measurements from each experiment, and then comparing the predicted Radiance with the ASTER measured Radiance. The results indicate the average difference between the predicted and the ASTER measured Radiances was no more than 0.5% or 0.4 K in any TIR band, demonstrating that the TIR bands have exceeded the preflight design accuracy of < 1 K for an at-sensor brightness temperature range of 270-340 K. The predicted and the ASTER measured Radiances were then used to assess how well the onboard calibration accounted for any changes in both the instrument gain and offset over time. The results indicate that the gain and offset were correctly determined using the onboard blackbody, and indicate a responsivity decline over the first 1400 days of the Terra mission.
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in flight validation and recovery of water surface temperature with landsat 5 thermal infrared data using an automated high altitude lake validation site at lake tahoe
IEEE Transactions on Geoscience and Remote Sensing, 2004Co-Authors: Simon J Hook, Frank D. Palluconi, A. Abtahi, R.c. Richards, S.g. Schladow, Gyanesh Chander, Julia A Barsi, Ronald E Alley, Brian L Markham, Dennis L HelderAbstract:The absolute radiometric accuracy of the thermal infrared band (B6) of the Thematic Mapper (TM) instrument on the Landsat-5 (L5) satellite was assessed over a period of approximately four years using data from the Lake Tahoe automated validation site (California-Nevada). The Lake Tahoe site was established in July 1999, and measurements of the skin and bulk temperature have been made approximately every 2 min from four permanently moored buoys since mid-1999. Assessment involved using a radiative transfer model to propagate surface skin temperature measurements made at the time of the L5 overpass to predict the at-sensor Radiance. The predicted Radiance was then convolved with the L5B6 system response function to obtain the predicted L5B6 Radiance, which was then compared with the Radiance measured by L5B6. Twenty-four cloud-free scenes acquired between 1999 and 2003 were used in the analysis with scene temperatures ranging between 4/spl deg/C and 22/spl deg/C. The results indicate L5B6 had a Radiance bias of 2.5% (1.6/spl deg/C) in late 1999, which gradually decreased to 0.8% (0.5/spl deg/C) in mid-2002. Since that time, the bias has remained positive (predicted minus measured) and between 0.3% (0.2/spl deg/C) and 1.4% (0.9/spl deg/C). The cause for the cold bias (L5 Radiances are lower than expected) is unresolved, but likely related to changes in instrument temperature associated with changes in instrument usage. The in situ data were then used to develop algorithms to recover the skin and bulk temperature of the water by regressing the L5B6 Radiance and the National Center for Environmental Prediction (NCEP) total column water data to either the skin or bulk temperature. Use of the NCEP data provides an alternative approach to the split-window approach used with instruments that have two thermal infrared bands. The results indicate the surface skin and bulk temperature can be recovered with a standard error of 0.6/spl deg/C. This error is larger than errors obtained with other instruments due, in part, to the calibration bias. L5 provides the only long-duration high spatial resolution thermal infrared measurements of the land surface. If these data are to be used effectively in studies designed to monitor change, it is essential to continue to monitor instrument performance in-flight and develop quantitative algorithms for recovering surface temperature.
D. Heath - One of the best experts on this subject based on the ideXlab platform.
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IGARSS - Transformation of Solar Disc Radiances into a Top of the Atmosphere Radiance Source for On-Orbit Solar Calibration of Terrestrial Radiance Measurements
2006 IEEE International Symposium on Geoscience and Remote Sensing, 2006Co-Authors: D. Heath, A. Slaymaker, M. KuesterAbstract:Characteristics have been measured for a series of transmission optical devices that are considered for use in transforming solar disc Radiances into a top of the atmosphere solar Radiance source which can be used to calibrate terrestrial Radiance measurements derived from orbiting remote sensing instruments. The types of transmission optical elements that were evaluated are a diffraction hole-plate, plates of fused silica and glass with ground surfaces, several types of microlens arrays and "engineered" diffusers. Collimated light from a diffuse source with approximately the angular solar diameter was imaged onto a CCD camera by a long focal length achromat at multiple narrow band wavelengths. The optical transform device was inserted into the beam of collimated radiation on the source side of the achromatic lens.
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Transformation of Solar Disc Radiances into a Top of the Atmosphere Radiance Source for On-Orbit Solar Calibration of Terrestrial Radiance Measurements
2006 IEEE International Symposium on Geoscience and Remote Sensing, 2006Co-Authors: D. Heath, A. Slaymaker, M. KuesterAbstract:Characteristics have been measured for a series of transmission optical devices that are considered for use in transforming solar disc Radiances into a top of the atmosphere solar Radiance source which can be used to calibrate terrestrial Radiance measurements derived from orbiting remote sensing instruments. The types of transmission optical elements that were evaluated are a diffraction hole-plate, plates of fused silica and glass with ground surfaces, several types of microlens arrays and "engineered" diffusers. Collimated light from a diffuse source with approximately the angular solar diameter was imaged onto a CCD camera by a long focal length achromat at multiple narrow band wavelengths. The optical transform device was inserted into the beam of collimated radiation on the source side of the achromatic lens.
