Mr. Robert B. Lee Profile

Mr. Robert B. Lee

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Publications (64)

PROCEEDINGS ARTICLE | October 22, 2013

Assessment of long scale plume transport to the US East coast using coordinated CREST lidar network and synergistic AERONET and satellite measurements

Proc. SPIE. 8894, Lidar Technologies, Techniques, and Measurements for Atmospheric Remote Sensing IX

KEYWORDS: MODIS, Data modeling, Optical properties, LIDAR, Aerosols, Satellites, Mass attenuation coefficient, Climatology, Atmospheric particles, Atmospheric modeling

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PROCEEDINGS ARTICLE | October 9, 2008

Degradation pattern of the ERBE wide field-of-view radiometer aboard the NOAA 9 spacecraft

Proc. SPIE. 7106, Sensors, Systems, and Next-Generation Satellites XII

KEYWORDS: Optical filters, Sun, Calibration, Quartz, Bidirectional reflectance transmission function, Domes, Radiometry, Shortwaves, Space operations, Solar radiation

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PROCEEDINGS ARTICLE | August 20, 2008

1999-2003 shortwave characterizations of Earth Radiation Budget Satellite (ERBS)/Earth Radiation Budget Experiment (ERBE) broadband active cavity radiometer sensors

Proc. SPIE. 7081, Earth Observing Systems XIII

KEYWORDS: Sun, Radio optics, Sensors, Calibration, Satellites, Ultraviolet radiation, Radiometry, Shortwaves, Space operations, Solar radiation

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PROCEEDINGS ARTICLE | October 5, 2007

Radiometric performance of the CERES Earth radiation budget climate record sensors on the EOS Aqua and Terra spacecraft

Proc. SPIE. 6677, Earth Observing Systems XII

KEYWORDS: Optical filters, Sensors, Calibration, Black bodies, Radiometry, Shortwaves, Earth's atmosphere, Space operations, Climatology, Environmental sensing

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PROCEEDINGS ARTICLE | December 30, 2004

On-orbit characterizations of Earth Radiation Budget Experiment broadband shortwave active cavity radiometer sensor responses

Proc. SPIE. 5660, Instruments, Science, and Methods for Geospace and Planetary Remote Sensing

KEYWORDS: Sensors, Calibration, Quartz, Satellites, Remote sensing, Radiometry, Shortwaves, Space operations, Solar radiation, Active sensors

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The NASA Earth Radiation Budget Experiment (ERBE) missions were designed to monitor long-term changes in the earth radiation budget components which may cause climate changes. During the October 1984 through September 2004 period, the NASA Earth Radiation Budget Satellite (ERBS)/ERBE nonscanning active cavity radiometers (ACR) were used to monitor long-term changes in the earth radiation budget components of the incoming total solar irradiance (TSI), earth-reflected TSI, and earth-emitted outgoing longwave radiation (OLR). The earth-reflected total solar irradiances were measured using broadband shortwave fused, waterless quartz (Suprasil) filters and ACR’s that were covered with a black paint absorbing surface. Using on-board calibration systems, 1984 through 1999, long-term ERBS/ERBE ACR sensor response changes were determined from direct observations of the incoming TSI in the 0.2-5 micrometer shortwave broadband spectral region. During the October 1984 through September 1999 period, the ERBS shortwave sensor responses were found to decrease as much as 8.8% when the quartz filter transmittances decreased due to direct exposure to TSI. On October 6, 1999, the on-board ERBS calibration systems failed. To estimate the 1999-2004, ERBS sensor response changes, the 1984-1997 NOAA-9, and 1986-1995 NOAA-10 Spacecraft ERBE ACR responses were used to characterize response changes as a function of exposure time. The NOAA-9 and NOAA-10 ACR responses decreased as much as 10% due to higher integrated TSI exposure times. In this paper, for each of the ERBS, NOAA-9, and NOAA-10 Spacecraft platforms, the solar calibrations of the ERBE sensor responses are described as well as the derived ERBE sensor response changes as a function of TSI exposure time. For the 1984-2003 ERBS data sets, it is estimated that the calibrated ERBE earth-reflected TSI measurements have precisions approaching 0.2 Watts-per-squared-meter at satellite altitudes.

PROCEEDINGS ARTICLE | December 30, 2004

Determination of CERES flight models 1 and 2 sensors zero-radiance response variability with elevation and azimuth scan angles on-orbit aboard TERRA Spacecraft

Proc. SPIE. 5652, Passive Optical Remote Sensing of the Atmosphere and Clouds IV

KEYWORDS: Bolometers, Aerospace engineering, Sensors, Calibration, Clouds, Black bodies, Shortwaves, Space operations, Atmospheric modeling, Instrument modeling

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PROCEEDINGS ARTICLE | November 4, 2004

Validation of spacecraft active cavity radiometer total solar irradiance (TSI): long-term measurement trends using proxy TSI least squares analyses

Proc. SPIE. 5570, Sensors, Systems, and Next-Generation Satellites VIII

KEYWORDS: Solar energy, Sensors, Satellites, Magnetism, Climate change, Radiometry, Space operations, Solar radiation, Atmospheric sciences, Climatology

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PROCEEDINGS ARTICLE | February 24, 2004

Calibrations of the Clouds and the Earth’s Radiant Energy System (CERES) instruments on the Terra and Aqua spacecrafts

Proc. SPIE. 5232, Remote Sensing for Agriculture, Ecosystems, and Hydrology V

KEYWORDS: Data modeling, Sensors, Calibration, Silicon, Lamps, Photodiodes, Black bodies, Shortwaves, Space operations, Instrument modeling

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PROCEEDINGS ARTICLE | February 16, 2004

Twelve-month running trends from Earth Radiation Budget Satellite (ERBS) active-cavity radiometric measurements and global surface temperatures

Proc. SPIE. 5235, Remote Sensing of Clouds and the Atmosphere VIII

KEYWORDS: Sensors, Calibration, Satellites, Climate change, Radiometry, Shortwaves, Data centers, Space operations, Climatology, Temperature metrology

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PROCEEDINGS ARTICLE | February 2, 2004

On-orbit calibrations of the ERBE active-cavity radiometers on the Earth Radiation Budget Satellite (ERBS): 1984-2002

Proc. SPIE. 5234, Sensors, Systems, and Next-Generation Satellites VII

KEYWORDS: Bolometers, Sun, Sensors, Calibration, Satellites, Black bodies, Radiometry, Shortwaves, Space operations, Solar radiation

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PROCEEDINGS ARTICLE | February 2, 2004

Method for comparison of GERB and CERES radiances

Proc. SPIE. 5234, Sensors, Systems, and Next-Generation Satellites VII

KEYWORDS: Solar energy, Sensors, Calibration, Satellites, Clouds, Bidirectional reflectance transmission function, Radiometry, Shortwaves, Space operations, Solar radiation

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PROCEEDINGS ARTICLE | November 10, 2003

On-orbit solar calibrations using the Aqua Clouds and Earth's Radiant Energy System (CERES) in-flight calibration system

Proc. SPIE. 5151, Earth Observing Systems VIII

KEYWORDS: Bolometers, Solar energy, Sun, Sensors, Calibration, Diffusers, Radiometry, Shortwaves, Space operations, Solar radiation

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PROCEEDINGS ARTICLE | November 10, 2003

Measurements of filtered lunar radiances using the NASA Terra spacecraft/CERES thermistor bolometer sensors during 2000 and 2001

Proc. SPIE. 5151, Earth Observing Systems VIII

KEYWORDS: Bolometers, Sensors, Calibration, Clouds, Solids, Black bodies, Shortwaves, Space operations, Temperature metrology, Instrument modeling

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Studies were conducted to define lunar radiances on an absolute radiometric scale tied to the International Temperature Scale of 1990 (ITS-90). The Clouds and the Earth's Radiant Energy System (CERES) thermistor bolometer sensor instruments were used to measure lunar radiances from the NASA Tropical Rainfall Measuring Mission (TRMM), Terra, and Aqua spacecraft platforms. Each CERES instrument package consisted of three different sensors: (1) broadband shortwave [0.3 to 5 micrometers]; (2) broadband total [0.3 to >100 micrometers]; and (3) narrowband, water vapor window [8 to 12 micrometers]. Moon-reflected solar radiances were measured with the shortwave sensor while both moon-reflected solar and moon-emitted longwave radiances were measured using the total sensor. The differences between the total and shortwave sensor measurements were used to determine the broadband longwave, moon-emitted radiances. The narrowband, water vapor window sensor measured only the longwave, moon-emitted radiances. The radiances were obtained as a function of phase angle (formed at the moon between directions to the sun and the spacecraft). The resulting filtered radiances were normalized to the mean sun-moon distance, one astronomical unit (AU), and to the mean earth-moon distance of 0.0026 AU (384,400 kilometers). 1998, 2000, and 2001, CERES lunar filtered measurements are presented, compared, and analyzed. Additional measurements are presented from the January 9, 2001, and May 16, 2003, total lunar eclipse events. Analyses of the Clouds and the Earth's Radiant Energy System (CERES) thermistor bolometer sensor observations of lunar radiances indicated that broadband shortwave and longwave lunar filtered radiances can be linked to a radiometric scale based upon an International Temperature Scale of 1990 (ITS-90) at absolute levels approaching ± 0.2 Wm^-2sr^-1. For a lunar image diameter of 31 minutes of arc, an emitting lunar disc temperature of approximately 400 Kelvin was estimated from the longwave radiances near 7-degree phase angle. The integration of the CERES unfiltered radiances over all reflection angles can be used to define the moon radiation budget (MRB).

PROCEEDINGS ARTICLE | April 18, 2003

The earth radiation budget experiment (ERBE) 15-year data set

Proc. SPIE. 4882, Remote Sensing of Clouds and the Atmosphere VII

KEYWORDS: Sensors, Calibration, Satellites, Scanners, Radiometry, Shortwaves, Data centers, Space operations, Solar radiation, Climatology

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PROCEEDINGS ARTICLE | April 8, 2003

Dome degradation pattern of the ERBE wide-field-of-view shortwave radiometer

Proc. SPIE. 4881, Sensors, Systems, and Next-Generation Satellites VI

KEYWORDS: Sun, Calibration, Quartz, Satellites, Computing systems, Domes, Radiometry, Shortwaves, Space operations, Solar radiation

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PROCEEDINGS ARTICLE | March 14, 2003

Performance studies of CERES sensors on Earth Science Enterprise (ESE) Terra mission using onboard calibrations and other validation methods

Proc. SPIE. 4886, Remote Sensing for Environmental Monitoring, GIS Applications, and Geology II

KEYWORDS: Bolometers, Mirrors, Sensors, Calibration, Space telescopes, Black bodies, Diffusers, Shortwaves, Space operations, Sensor calibration

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Clouds and the Earth's Radiant Energy system (CERES) sensors provide accurate measurements for the long-term monitoring of the Earth's radiation budget components such as reflected shortwave and emitted longwave radiances. CERES instruments has three scanning thermistor bolometers that measure broadband radiances in the shortwave (0.3 to 5.0 micrometer), total (0.3 to >100 micrometer) and in 8 - 12 micrometer water vapor window regions. Two of the CERES instruments (Flight Models 1 and 2(FM1&2)) are part of ESE Terra mission and has been successfully making Earth radiance measurements for the past two years. The CERES sensors are calibrated in flight using the on-board blackbody sources and a tungsten lamp known as internal calibration module (ICM) as well as a solar diffuser plate known as the Mirror Attenuator Mosaic (MAM). The ICM calibrations is used to determine the sensor measurement precisions during the ground, ground to orbit, and the on-orbit phases of the sensor calibrations. The MAM calibrations define on-orbit shifts or drifts in shortwave and total sensor responses. The traditional validation studies conducted to understand the stability of the sensors' performance include the analysis of Tropical Mean (TM) value using nadir tropical ocean measurements and three channel intercomparison between sensors of the same instrument. With two CERES instruments on the same platform, an additional study utilizing direct comparison of similar sensor measurements viewing the same geolocation is also conducted. The ICM results have shown that total sensors on both instruments have shown a variation of 0.25 and 0.5 percent respectively, whereas the shortwave sensors show a minimal change of 0.2 percent each. With high variability during the initial year, the MAM results have stabilised within the 0.5 percent precision range in the second year. The validation studies have shed additional light into the behaviour of total sensors in the shortwave and longwave spectral regions. The TM longwave day night difference (DN) derived from longwave sensors of each CERES instrument indicate that the FM1 sensors have varied about 0.25 watts m^-2sr^-1, whereas the total sensor in FM2 has a gradual rise of 1.4 watts m^-2sr^-1 in a 30 month period. This paper discusses briefly the contribution of each calibration and validation study in understanding the CERES sensors' behavior and the results from both Terra instruments' sensors. It also discusses how the various analyses are put together in understanding the rise seen in the total sensor of FM2 instrument.

PROCEEDINGS ARTICLE | September 24, 2002

On-orbit radiometric calibrations of the Earth Radiation Budget Experiment (ERBE) active-cavity radiometers on the Earth Radiation Budget Satellite (ERBS)

Proc. SPIE. 4814, Earth Observing Systems VII

KEYWORDS: Sensors, Calibration, Satellites, Resistance, Lamps, Black bodies, Radiometry, Shortwaves, Space operations, Solar radiation

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PROCEEDINGS ARTICLE | January 18, 2002

Optical design of the CERES telescope

Proc. SPIE. 4483, Earth Observing Systems VI

KEYWORDS: Point spread functions, Telescopes, Optical filters, Mirrors, Sensors, Space telescopes, Ray tracing, Shortwaves, Space operations, Solar radiation

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PROCEEDINGS ARTICLE | February 21, 2001

Relationship between the Clouds and the Earth's Radiant Energy System (CERES) measurements and surface temperatures of selected ocean regions

Proc. SPIE. 4150, Optical Remote Sensing of the Atmosphere and Clouds II

KEYWORDS: Bolometers, Optical filters, Sensors, Calibration, Satellites, Clouds, Space telescopes, Shortwaves, Sensor calibration, Temperature metrology

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PROCEEDINGS ARTICLE | February 9, 2001

Broadband measurements of lunar radiances using the Tropical Rainfall Measuring Mission (TRMM) spacecraft/Clouds and the Earth's Radiant Energy System (CERES) sensors

Proc. SPIE. 4169, Sensors, Systems, and Next-Generation Satellites IV

KEYWORDS: Bolometers, Mirrors, Sensors, Calibration, Lamps, Clouds, Image sensors, Black bodies, Shortwaves, Space operations

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12 Currently, the moon is being used as a radiometric target to determine on-orbit relative shifts or shifts in the responses of certain spacecraft shortwave sensors. Along these lines, the 1998 Tropical Rainfall Measuring Mission (TRMM) Spacecraft/Clouds and the Earth's Radiant Energy System (CERES) thermistor bolometer sensor observations of lunar radiances were analyzed to evaluate the feasibility using the lunar radiances to calibrate the CERES sensor responses. Over a 5 to 110 degree phase angle range, the CERES sensors were used to measure: broadband shortwave (0.3 micrometers to 5.0 micrometers ) moon-reflected solar filtered radiances; broadband total (0.3 micrometers to more than 100 micrometers ) moon- reflected solar and moon-emitted longwave filtered radiances; and narrowband window (8 micrometers to 12 micrometers ) moon- emitted longwave filtered radiances. The TRMM/CERES on-orbit radiance measurements are tied to an International Temperature Scale of 1990 (ITS-90) modeled radiometric scale at uncertainty levels approaching 0.2% (0.2 Wm^-2sr^-1). Therefore, the TRMM/CERES measurements should be useful in forecasting the precisions of scheduled CERES lunar measurements from the NASA Terra and Aqua Spacecraft platforms near phase angle of 22 and 55 degrees, respectively. The 7-degree phase angle, 1998 CERES shortwave, total, and window measurements yielded lunar filtered radiances of approximately 4.5+/- 0.2, 24.4+/- 0.5, and 4.5+/- 0.2 Wm^-2sr^-1, respectively. These lunar measurements indicate that broadband shortwave radiances can be characterized at the 5% uncertainty range. The 7-degree, shortwave lunar radiances were found to be approximately 1.5 and 3 times brighter greater the corresponding radiances found at the 22-degree and 55-degree phase angles, respectively. Therefore, the Terra and Aqua CERES lunar shortwave measurements near 22.5- degree and 55-degree phase angles should yield projected precisions in the 7% and 15% range, respectively. The CERES lunar filtered radiance are presented and discussed. Research efforts are outlined briefly for comparing the total sensor broadband and window narrowband longwave lunar radiances during the January 9, 2001 lunar eclipse.

PROCEEDINGS ARTICLE | February 9, 2001

Validation of CERES/TERRA data

Proc. SPIE. 4169, Sensors, Systems, and Next-Generation Satellites IV

KEYWORDS: MODIS, Sensors, Calibration, Reflectivity, Clouds, Radiometry, Shortwaves, Earth's atmosphere, Space operations, Solar radiation

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PROCEEDINGS ARTICLE | January 31, 2001

Validation and analysis of Earth Radiation Budget active-cavity radiometric data (1985-1999)

Proc. SPIE. 4168, Remote Sensing of Clouds and the Atmosphere V

KEYWORDS: Sun, Sensors, Calibration, Satellites, Data acquisition, Black bodies, Radiometry, Shortwaves, Climatology, Temperature metrology

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PROCEEDINGS ARTICLE | November 15, 2000

Determination and validation of slow mode coefficients of the Clouds and the Earth's Radiant Energy System (CERES) scanning thermistor bolometers

Proc. SPIE. 4135, Earth Observing Systems V

KEYWORDS: Bolometers, Aerospace engineering, Sensors, Calibration, Clouds, Black bodies, Fermium, Shortwaves, Space operations, Instrument modeling

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PROCEEDINGS ARTICLE | November 15, 2000

Terra spacecraft CERES flight model 1 and 2 sensor measurement precisions: ground-to-flight determinations

Proc. SPIE. 4135, Earth Observing Systems V

KEYWORDS: Sensors, Calibration, Lamps, Photodiodes, Black bodies, Shortwaves, Chlorine, Space operations, Sensor calibration, Environmental sensing

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PROCEEDINGS ARTICLE | November 15, 2000

On-orbit solar calibrations using the Terra Clouds and Earth's Radiant Energy System (CERES) in-flight calibration system

Proc. SPIE. 4135, Earth Observing Systems V

KEYWORDS: Bolometers, Solar energy, Sun, Sensors, Calibration, Diffusers, Radiometry, Shortwaves, Space operations, Solar radiation

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PROCEEDINGS ARTICLE | November 15, 2000

Clouds and the Earth's Radiant Energy System (CERES) spectral response characterizations

Proc. SPIE. 4135, Earth Observing Systems V

KEYWORDS: Optical filters, Mirrors, Sensors, Calibration, Reflectivity, Fourier transforms, Clouds, Shortwaves, Planets, Signal detection

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PROCEEDINGS ARTICLE | July 17, 2000

Early trends of the Clouds and the Earth's Radiant Energy System (CERES) instrument's performance using in-flight calibration sources for the Earth Science Enterprise (ESE) TERRA mission

Proc. SPIE. 4030, Infrared Imaging Systems: Design, Analysis, Modeling, and Testing XI

KEYWORDS: Bolometers, Sensors, Calibration, Lamps, Clouds, Black bodies, Shortwaves, Earth sciences, Space operations, Sensor calibration

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PROCEEDINGS ARTICLE | December 28, 1999

Ground through on-orbit transfer of the International Temperature Scale of 1990 (ITS-90): radiometeric scale using the CERES thermistor bolometers and built-in flight calibration systems

Proc. SPIE. 3870, Sensors, Systems, and Next-Generation Satellites III

KEYWORDS: Bolometers, Sensors, Calibration, Tungsten, Lamps, Black bodies, Aluminum, Shortwaves, Space operations, Sensor calibration

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The Clouds and Earth's Radiant Energy System (CERES thermistor bolometers were calibrated using filtered radiances, characterized on an International Temperature Scale of 1990 (ITS-90) derived absolute radiometric scale. Longwave filtered radiances were characterized using the optical and geometric surface properties of the reference Narrow-Field-of-View Blackbody (NFBB), the NFBB temperature measurements from the ITS-90 calibrated platinum resistance thermometers (PRT) embedded in the blackbodies, and the spectral responses of the CERES bolometers. Shortwave filtered radiances were characterized using the cryogenically-cooled Transfer Active Cavity Radiometer (TACR) which was an ITS-90 transfer standard, and using the spectral responses of the bolometers. In ground vacuum facilities, the ITS-90, temperature-based radiometric scale was transferred to the CERES bolometers. As ITS-90 transfer standards, the bolometers were used to characterize the emitted filtered radiances from in-flight systems: (1) the internal calibration module (ICM) which consisted of anodized aluminum blackbodies and tungsten lamp sources; and (2) mirror attenuator mosaic (MAM) which was an aluminum solar diffuser plate, built into the bolometer instrumentation. From the ground [October 1995] through the on-orbit phases [December 1998 - July 1999] of the Tropical Rainfall Measuring Mission (TRMM) Spacecraft CERES instrument mission, the stabilities of the bolometer's responses were assessed from periodical observations of the in-flight calibration systems radiances. Each CERES instrument package consisted of broadband shortwave [0.3 micrometer to 5.0 micrometer], broadband total [0.3 micrometer to greater than 100 micrometer], and narrowband window [8 micrometer and 12 micrometer], scanning thermistor bolometer sensor units; and of in-flight calibration systems. Between the ground and initial on-orbit calibrations, the TRMM CERES bolometers and the built-in, flight calibration system sources maintained their filtered radiance measurement ties to ITS-90 at the plus or minus 0.2 Wm^-2sr^-1 precision level. On-orbit calibration studies indicate that the radiance measurements were stable at the plus or minus 0.2 Wm^-2sr^-1 precision level. The ground and on- orbit calibration results are presented and discussed.

PROCEEDINGS ARTICLE | December 8, 1999

Self-validation of radiance measurements from the CERES (TRMM) instrument

Proc. SPIE. 3867, Satellite Remote Sensing of Clouds and the Atmosphere IV

KEYWORDS: Statistical analysis, Sensors, Satellites, Remote sensing, Error analysis, Clouds, Data acquisition, Analytical research, Shortwaves, Instrument modeling

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PROCEEDINGS ARTICLE | September 24, 1999

Point response characteristics for the CERES/EOS-PM, FM3, and FM4 instruments

Proc. SPIE. 3750, Earth Observing Systems IV

KEYWORDS: Point spread functions, Data modeling, Phase modulation, Sensors, Calibration, Data acquisition, Fermium, Radiometry, Shortwaves, Instrument modeling

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PROCEEDINGS ARTICLE | September 24, 1999

Analyses of on-orbit determinations of the Clouds and the Earth's Radiant Energy System (CERES) thermistor bolometer sensor zero-radiance offsets

Proc. SPIE. 3750, Earth Observing Systems IV

KEYWORDS: Bolometers, Solar energy, Sensors, Calibration, Clouds, Black bodies, Shortwaves, Space operations, Content addressable memory, Instrument modeling

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PROCEEDINGS ARTICLE | December 21, 1998

End-to-end spectral characterization of the Clouds and the Earth's Radiant Energy System (CERES) thermistor bolometer radiometers

Proc. SPIE. 3498, Sensors, Systems, and Next-Generation Satellites II

KEYWORDS: Bolometers, Optical filters, Calibration, Spectroscopy, Fourier transforms, Clouds, Radiometry, Shortwaves, Performance modeling, Systems modeling

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PROCEEDINGS ARTICLE | December 14, 1998

CERES/TRMM mission: early results

Proc. SPIE. 3495, Satellite Remote Sensing of Clouds and the Atmosphere III

KEYWORDS: Sensors, Calibration, Clouds, Bidirectional reflectance transmission function, Black bodies, Radiometry, Shortwaves, Space operations, Solar radiation, Anisotropy

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