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Search Publications by: B. Carol Johnson (Fed)

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Displaying 76 - 100 of 358

The Marine Optical BuoY (MOBY) Radiometric Calibration and Uncertainty Budget for Ocean Color Satellite Sensor Vicarious Calibration

December 31, 2008
Author(s)
M Feinholz, B. Carol Johnson, Steven W. Brown, S Flora, M Yarbrough, Terrance Houlihan, D Peters, Yong S. Kim, J Mueller, Dennis Clark
For the past decade, the Marine Optical Buoy (MOBY), an autonomous radiometric buoy stationed in the waters off Lanai, Hawaii, has been the primary in-water oceanic observatory for the vicarious calibration of the U. S. satellite ocean color sensors

Intercomparisions of Reflectance Measurements

October 16, 2008
Author(s)
P Y. Barnes, B. Carol Johnson, James J. Butler, C J. Bruegge, S F. Biggar, P R. Spyak, M M. Pavlov, E A. Early
A comparison of spectral diffuse reflectance between different national standards laboratories is being planned under the direction of the Comit* Consultatif de Photom*trie et Radiom*trie (CCPR). A similar comparison of bi-directional reflectance

Metrology for Remote Sensing Radiometry

October 16, 2008
Author(s)
B. Carol Johnson, Steven W. Brown, Joseph P. Rice
Metrology, the science of measurement, is discussed in terms of measurements of radiant flux and associated quantities. Radiometric measurements are naturally remote, that is, they are non-contact. A broad application is Earth science, as global

Overview of Radiation Thermometry

October 16, 2008
Author(s)
B. Carol Johnson
Researchers in the Optical Technology Division utilize measurements of radiant flux to determine temperature. This includes the dissemination of the ITS-90 above 961.78 degrees C using spectral radiance ratios (optical pyrometry) and absolute measurements

Calibration of a Radiance Standard for the NPP/OMPS Instrument

October 9, 2008
Author(s)
Bettye C. Johnson, James J. Butler, Scott J. Janz, Robert D. Saunders, John W. Cooper, Matthew G. Kowalewski, R Barnes
In June 2007, a spherical integrating source was calibrated in the National Aeronautics and Space Administration(NASA) Goddard Space Flight Center’s (GSFC) Calibration Facility as part of the prelaunch characterization program for the NPOESS Preparatory

Measurement science for climate remote sensing

August 20, 2008
Author(s)
Gerald T. Fraser, Steven W. Brown, Raju V. Datla, Bettye C. Johnson, Keith R. Lykke, Joseph P. Rice
The Earth s climate is very complex and highly variable, making it difficult to measure and model small changes that occur over decadal and longer time scales. The resulting uncertainties in measurement and modeling underlie the longterm debate over the

The Marine Optical BuoY (MOBY) Radiometric Calibration and Uncertainty Budget for Ocean Color Satellite Sensor Vicarious Calibration

November 1, 2007
Author(s)
Steven W. Brown, S Flora, M Feinholz, M Yarbrough, Terrance Houlihan, D Peters, Yong S. Kim, J Mueller, Bettye C. Johnson, Dennis Clark
For the past decade, the Marine Optical Buoy (MOBY), an autonomous radiometric buoy stationed in the waters off Lanai, Hawaii, has been the primary in-water oceanic observatory for the vicarious calibration of U. S. satellite ocean color sensors, including

Results in Coastal Waters With High Resolution In Situ Spectral Radiometry: The Marine Optical System ROV

October 5, 2007
Author(s)
M Yarbrough, M Feinholz, S Flora, Terrance Houlihan, B. Carol Johnson, Yong S. Kim, Marilyn Y. Murphy, Michael Ondrusek, D K. Clark
The solar normalized water-leaving spectral radiance is a basic ocean color remote-sensing parameter required for the vicarious calibration and bio-optical product development. Determination of normalized water-leaving spectral radiance using in-water

Area Measurements of Apertures for Exo-Atmospheric Solar Irradiance for JPL

September 13, 2007
Author(s)
Maritoni A. Litorja, Bettye C. Johnson, J B. Fowler
A comparison of the area measurements of the limiting apertures used for total solar irradiance measurements in the Active Cavity Radiometer Irradiance Monitor II (ACRIM II) and Active Cavity Radiometer Irradiance Monitor III (ACRIM III) were conducted

Absolute Flux Calibrations of Stars

August 30, 2007
Author(s)
Gerald T. Fraser, Steven W. Brown, Howard W. Yoon, Bettye C. Johnson, Keith R. Lykke
Absolute stellar photometry is based on 1970s terrestrial measurements of the star Vega referenced against the Cu fixed-point blackbody. Significant advances in absolute radiometry have been made in the last 30 years that offer the potential to improve

Simultaneous Measurement of Up-Welling Spectral Radiance Using a Fiber-Coupled CCD Spectrograph

August 26, 2007
Author(s)
M Yarbrough, S Flora, M Feinholz, Terrance Houlihan, Yong S. Kim, Steven W. Brown, B. Carol Johnson, Kenneth Voss, Dennis Clark
Determination of the water-leaving spectral radiance using in-water instrumentation requires measurements of the up-welling spectral radiance (Lu) at several depths. If these measurements are separated in time, changes in the measurement conditions result