Abstract

An analysis of the thermal response of a fused silica hemispherical dome filter in a wide field-of-view (WFOV) shortwave radiometer for obtaining earth radiation budget measurements is presented. The impact of the filter thermal response on the dc detector (a thermopile) and on the resulting measurement uncertainty is evaluated. It is shown that the hemispherical filter material maintains neither a uniform nor constant temperature distribution as it responds to changes in the radiation emitted from earth. Accurate determination of terrestrial shortwave irradiance requires knowledge of the dome filter thermal response because the thermopile responds to changes in the dome temperature as well as the shortwave scene. Data are presented that show that variations in the dome temperature distribution from calibration conditions can result in a measurement uncertainty of several W/m2 if not properly accounted for in the interpretation of the measurement. Design approaches, ground calibration, and data reduction techniques that can reduce this measurement uncertainty by an order of magnitude are presented.

© 1980 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |

  1. J. E. Cooper, C. V. Woerner, “The Earth Radiation Budget Satellite System of the Early 1980s,” in Proceedings, Fourth Symposium on Meteorological Observations and Instrumentation, Denver, 10–14 Apr. 1978.
  2. J. E. Cooper, C. V. Woerner, “System Implementation for Earth Radiation Budget Satellite System,” at Third Conference on Atmospheric Radiation, Davis, Calif., 28–30 June 1978.
  3. J. R. Mahan, M. R. Luther, “Thermal Model of a Filtered Radiometer,” at Third Conference on Atmospheric Radiation, Davis, Calif., 28–30 June 1978.
  4. G. G. Campbell and T. H. Vonder Haar of Colorado State U. developed for NASA Langley Research Center under contract NAS1-12106, a computer program capable of simulating the earth's reflected and emitted radiation as a function of time and space based on Nimbus 3 measurements.
  5. T. H. Vonder Haar, W. H. Wallschlaeger, “Design Definition Study of the Earth Radiation Budget Satellite System,” NASA CR-158934 (Aug.1978).

Cooper, J. E.

J. E. Cooper, C. V. Woerner, “The Earth Radiation Budget Satellite System of the Early 1980s,” in Proceedings, Fourth Symposium on Meteorological Observations and Instrumentation, Denver, 10–14 Apr. 1978.

J. E. Cooper, C. V. Woerner, “System Implementation for Earth Radiation Budget Satellite System,” at Third Conference on Atmospheric Radiation, Davis, Calif., 28–30 June 1978.

Luther, M. R.

J. R. Mahan, M. R. Luther, “Thermal Model of a Filtered Radiometer,” at Third Conference on Atmospheric Radiation, Davis, Calif., 28–30 June 1978.

Mahan, J. R.

J. R. Mahan, M. R. Luther, “Thermal Model of a Filtered Radiometer,” at Third Conference on Atmospheric Radiation, Davis, Calif., 28–30 June 1978.

Vonder Haar, T. H.

T. H. Vonder Haar, W. H. Wallschlaeger, “Design Definition Study of the Earth Radiation Budget Satellite System,” NASA CR-158934 (Aug.1978).

Wallschlaeger, W. H.

T. H. Vonder Haar, W. H. Wallschlaeger, “Design Definition Study of the Earth Radiation Budget Satellite System,” NASA CR-158934 (Aug.1978).

Woerner, C. V.

J. E. Cooper, C. V. Woerner, “System Implementation for Earth Radiation Budget Satellite System,” at Third Conference on Atmospheric Radiation, Davis, Calif., 28–30 June 1978.

J. E. Cooper, C. V. Woerner, “The Earth Radiation Budget Satellite System of the Early 1980s,” in Proceedings, Fourth Symposium on Meteorological Observations and Instrumentation, Denver, 10–14 Apr. 1978.

Other (5)

J. E. Cooper, C. V. Woerner, “The Earth Radiation Budget Satellite System of the Early 1980s,” in Proceedings, Fourth Symposium on Meteorological Observations and Instrumentation, Denver, 10–14 Apr. 1978.

J. E. Cooper, C. V. Woerner, “System Implementation for Earth Radiation Budget Satellite System,” at Third Conference on Atmospheric Radiation, Davis, Calif., 28–30 June 1978.

J. R. Mahan, M. R. Luther, “Thermal Model of a Filtered Radiometer,” at Third Conference on Atmospheric Radiation, Davis, Calif., 28–30 June 1978.

G. G. Campbell and T. H. Vonder Haar of Colorado State U. developed for NASA Langley Research Center under contract NAS1-12106, a computer program capable of simulating the earth's reflected and emitted radiation as a function of time and space based on Nimbus 3 measurements.

T. H. Vonder Haar, W. H. Wallschlaeger, “Design Definition Study of the Earth Radiation Budget Satellite System,” NASA CR-158934 (Aug.1978).

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (7)

Fig. 1
Fig. 1

Thermal model schematic diagram of shortwave WFOV radiometer.

Fig. 2
Fig. 2

Simulated terrestrial irradiance at 600 km (June).

Fig. 3
Fig. 3

Dome node temperature and terrestrial longwave irradiance at satellite altitude (600 km, June orbit).

Fig. 4
Fig. 4

Error in shortwave irradiance determination (600 km, June orbit).

Fig. 5
Fig. 5

Earth radiation budget WFOV shortwave channel data reduction flow chart.

Fig. 6
Fig. 6

Error in shortwave irradiance determination using an iterative data reduction technique (600 km, June orbit).

Fig. 7
Fig. 7

Response characteristics of WFOV shortwave radiometer calibrated at discrete dome temperature distributions.

Tables (2)

Tables Icon

Table I Shortwave Channel Measurement Error Statistics Using 309-K Average Dome Temperature Calibration Data

Tables Icon

Table II Shortwave Channel Measurement Error Statistics Using Iterative Data Reduction Technique

Equations (3)

Equations on this page are rendered with MathJax. Learn more.

H R = 1 τ d , s [ V S τ d , l H E τ d , l a σ T a 4 F e a 1 1 ρ d , l F d d ( d σ T d 4 + ρ d , l b σ T b 4 F d b ) ( ρ d , l d F d e 1 ρ d , l F d d 1 ) σ T h 4 ] ,
σ T d 4 = 0.035 H E + 508.1 .
H E = H T H R .

Metrics