• Cao, C., Weinreb M. , and Kaplan S. , 2004: Verification of the HIRS spectral response functions for more accurate atmospheric sounding. Proc. Conf. on Characterization and Radiometric Calibration for Remote Sensing, Logan, UT, Utah State University, CD-ROM.

  • Cao, C., Xu H. , Sullivan J. , McMillin L. , Ciren P. , and Hou Y. , 2005: Inter-satellite calibration of the High Resolution Infrared Radiation Sounders on NOAA-15, -16, and -17 from Simultaneous Nadir Overpass Observations. J. Atmos. Oceanic Technol., 22 , 381395.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Goodrum, G., Kidwell K. B. , and Winston W. , 2000: NOAA KLM User’s Guide. Department of Commerce, Washington, DC. [Available online at http://www2.ncdc.noaa.gov/docs/klm/.].

  • ITT, 1996: High Resolution Infrared Radiation Sounder HIRS/4 Technical Description. ITT Aerospace/Communications Division, Contract NAS5-30384, Doc. 8168948, 183 pp.

  • ITT, 1998: High Resolution Infrared Radiation Sounder HIRS/3 Instrument Manual and Alignment/Calibration Handbook & Optical Data. ITT Aerospace/Communications Division, Contract NAS5-30384, Doc. 8162669, 706 pp.

  • Kidwell, K., cited. 1998: Appendix M: New HIRS calibration procedure (NOAA-12 only). NOAA Polar Orbiter data user’s guide, NOAA/NESDIS. [Available online at http://www2.ncdc.noaa.gov/docs/podug/html/m/app_m.htm.].

  • Kigawa, S., and Mo T. , 2002: An algorithm for correction of lunar contamination in AMSU-A data. NOAA Tech. Rep., NESDIS 111, U.S. Department of Commerce, 30 pp.

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 110 54 3
PDF Downloads 68 32 1

An Improved Algorithm for the Operational Calibration of the High-Resolution Infrared Radiation Sounder

View More View Less
  • 1 NOAA/NESDIS/Center for Satellite Applications and Research, Camp Springs, Maryland
  • | 2 Science and Technology Corporation, Greenbelt, Maryland
  • | 3 QSS Group, Inc., Lanham, Maryland
Restricted access

Abstract

Radiance data from the High-Resolution Infrared Radiation Sounder (HIRS) have been used routinely in both direct radiance assimilation for numerical weather prediction and climate change detection studies. The operational HIRS calibration algorithm is critical for producing accurate radiance to meet the user’s needs, and it has significant impacts on products at all levels. Since the HIRS does not calibrate every scan line, the calibration coefficients between calibration cycles have to be interpolated based on a number of assumptions. In the more than 25-yr history of operational HIRS calibration, several interpolation methods have been used and, unfortunately, depending on which method is used, these algorithms can produce HIRS level 1b radiance data with significant differences. By analyzing the relationship between the instrument self-emission and gain change during filter temperature fluctuations, in this paper a significant flaw in the previous operational calibration algorithm (version 3) is identified. This caused calibration errors greater than 0.5 K and periodically degraded the HIRS radiance data quality of NOAA-15, -16, and -17 between 1998 and 2005. A new HIRS calibration algorithm (version 4) is introduced to improve the calibration accuracy, along with better indicators for instrument noise in the level 1b data. The new algorithm has been validated in parallel tests before it became operational at NOAA/National Environmental Satellite Data and Information Service (NESDIS). Test results show that significant improvements in calibration accuracy can be achieved especially for NOAA-15/HIRS. Several areas of further calibration improvements are also identified. The new algorithm has been used for all operational satellites at NOAA/NESDIS since 28 April 2005.

Corresponding author address: Dr. Changyong Cao, NOAA/NESDIS/Center for Satellite Applications and Research, 5200 Auth Rd., WWB, Rm. 712, Camp Springs, MD 20746. Email: changyong.cao@noaa.gov

Abstract

Radiance data from the High-Resolution Infrared Radiation Sounder (HIRS) have been used routinely in both direct radiance assimilation for numerical weather prediction and climate change detection studies. The operational HIRS calibration algorithm is critical for producing accurate radiance to meet the user’s needs, and it has significant impacts on products at all levels. Since the HIRS does not calibrate every scan line, the calibration coefficients between calibration cycles have to be interpolated based on a number of assumptions. In the more than 25-yr history of operational HIRS calibration, several interpolation methods have been used and, unfortunately, depending on which method is used, these algorithms can produce HIRS level 1b radiance data with significant differences. By analyzing the relationship between the instrument self-emission and gain change during filter temperature fluctuations, in this paper a significant flaw in the previous operational calibration algorithm (version 3) is identified. This caused calibration errors greater than 0.5 K and periodically degraded the HIRS radiance data quality of NOAA-15, -16, and -17 between 1998 and 2005. A new HIRS calibration algorithm (version 4) is introduced to improve the calibration accuracy, along with better indicators for instrument noise in the level 1b data. The new algorithm has been validated in parallel tests before it became operational at NOAA/National Environmental Satellite Data and Information Service (NESDIS). Test results show that significant improvements in calibration accuracy can be achieved especially for NOAA-15/HIRS. Several areas of further calibration improvements are also identified. The new algorithm has been used for all operational satellites at NOAA/NESDIS since 28 April 2005.

Corresponding author address: Dr. Changyong Cao, NOAA/NESDIS/Center for Satellite Applications and Research, 5200 Auth Rd., WWB, Rm. 712, Camp Springs, MD 20746. Email: changyong.cao@noaa.gov

Save