Korean Journal of Remote Sensing (대한원격탐사학회지)

Korean Society of Remote Sensing (대한원격탐사학회)
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Examining Influences of Asian dust on SST Retrievals over the East Asian Sea Waters Using NOAA AVHRR Data

NOAA AVHRR 자료를 이용한 해수면온도 산출에 황사가 미치는 영향

  • Chun, Hyoung-Wook (School of Earth and Environmental Sciences Seoul National University) ;
  • Sohn, Byung-Ju (School of Earth and Environmental Sciences Seoul National University)
  • 전형욱 (서울대학교 지구환경과학부) ;
  • 손병주 (서울대학교 지구환경과학부)
  • Published : 2009.02.28
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Abstract

This research presents the effect of Asian dust on the derived sea surface temperature (SST) from measurements of the Advanced Very High Resolution Radiometer (AVHRR) instrument flown onboard NOAA polar orbiting satellites. To analyze the effect, A VHRR infrared brightness temperature (TB) is estimated from simulated radiance calculated from radiative transfer model on various atmospheric conditions. Vertical profiles of temperature, pressure, and humidity from radiosonde observation are used to build up the East Asian atmospheric conditions in spring. Aerosol optical thickness (AOT) and size distribution are derived from skyradiation measurements to be used as inputs to the radiative transfer model. The simulation results show that single channel TB at window region is depressed under the Asian dust condition. The magnitude of depression is about 2K at nadir under moderate aerosol loading, but the magnitude reaches up to 4K at slant path. The dual channel difference (DCD) in spilt window region is also reduced under the Asian dust condition, but the reduction of DCD is much smaller than that shown in single channel TB simulation. Owing to the depression of TB, SST has cold bias. In addition, the effect of AOT on SST is amplified at large satellite zenith angle (SZA), resulting in high variance in derived SSTs. The SST depression due to the presence of Asian dust can be expressed as a linear function of AOT and SZA. On the basis of this relationship, the effect of Asian dust on the SST retrieval from the conventional daytime multi-channel SST algorithm can be derived as a function of AOT and SZA.

본 연구에서는 NOAA AVHRR 밝기온도 자료로부터 해수면 온도(SST) 산출에 황사 에어로솔은 미치는 영향을 복사전달 모델을 사용하여 분석하고, SST 복원 알고리즘을 개선하였다. 봄철의 황사에 의한 AVHRR 밝기온도 변화를 모의하기 위한 복사전달 모델의 입력 자료로서 지상 태양광 관측 자료로부터 분석한 황사 에어로솔 광학적 특성 (에어로솔 광학적 두께 및 크기분포)과 라디오 존데 연직분포 자료(기압, 기온, 및 습도)를 이용하였다. 황사 에어로솔은 적외선 복사대에서 흡수에 비해 산란이 매우 큼을 보였으며, 이러한 특징은 지표면에서 방출되는 상향복사량을 산란시켜 대기상부에서 관측되는 밝기 온도를 감소시키는 경향과 관련이 있다. 광학적 두께가 1인 황사의 경우 직하점에서 약 2 K, 위성 천정각이 $50^{\circ}$인 경우에는 약 4 K의 감쇄를 유발하였다. 황사 존재시 AVHRR 적의채널 11, $12{\mu}m$의 밝기온도 차 역시 감소하는 경향을 보이고 있지만 그 값은 미미하였다. 기존 SST 복원 알고리즘은 황사발생시 SST를 실제 값보다도 낮게 산출함을 보였으며, 이를 보정하기 위해 에어로솔 광학적 두께, $11{\mu}m$에서의 밝기온도, 그리고 위성 천정각을 추가하여 알고리즘을 개선하였다. 개선된 SST 복원 알고리즘은 황사의 두께가 1인 경우 2.7 K정도의 오차를 개선하였다.

Keywords

References

  1. 엄영대, 손병주, 2003. GMS-5 위성의 가시자료를 이용한 동아시아 지역의 에어로솔 광학두께 추정. 대기, 15: 203-211
  2. Ahn, M. H., J. M. Koo, C. Y. Chung, and J. C. Nam, 2003. Effect of the tropospheric dust on the sea surface temperature derivation from the GMS-5 IR data. J. Korean Soc. Remote Sens., 39: 653-666
  3. Barton, I. J., 1995. Satellite-derived sea surface temperatures: Current status. J Geophys. Res., 100: 8777-8790 https://doi.org/10.1029/95JC00365
  4. Emery, W. J., S. Castro, G. A. Wich, P. Schluessel, and C. Donion, 2001. Estimating sea surface temperature from infrared satellite and in situ temperature data, Bull. Amer. Meteo. Soc., 82: 2773-2785 https://doi.org/10.1175/1520-0477(2001)082<2773:ESSTFI>2.3.CO;2
  5. Elliot, W. P. and D. J. Gaffen, 1991. On the utility of radiosonde humidity archives for climate studies. Bull. Amer. Meteor. Soc., 72: 1507-1520 https://doi.org/10.1175/1520-0477(1991)072<1507:OTUORH>2.0.CO;2
  6. Fukushima, H., M. Schmidt, B. J. Sohn, W. Takahashi, M. Toratani, and I. Uno, 2000. Asian dust: Spatial and optical properties as seen by satellite ocean color sensors, Proc. 2000 Int. Geosci. and Remote Sensing Symposium (IGARSS 2000), Honolulu, Hawaii, IEEE: 1616-1618
  7. Joussaume, S., 1990. Three-dimensional simulations of the atmospheric cycle of desert dust particles using a general circulation model, J. Geophys. Res., 95: 1909-1941 https://doi.org/10.1029/JD095iD02p01909
  8. Kim, D. H., B. J. Sohn, T. Nakajima, T. Takamura, T. Takemura, B. C. Choi, and S. C. Yoon, 2004. Aerosol optical properties over East Asia determined from ground-based sky radiation measurements, J. Geophys. Res., 92: 95-115 https://doi.org/10.1029/JA092iA01p00095
  9. Lee, Y. H. and M. H. Ahn, 2001. The impact of high resolution SST on the performance of temperature prediction in a short-range prediction, J. Kor. Meteo. Soc., 37: 607-619
  10. May, D. A., L. L. Stowe, and J. D. Hawkins, 1992. A correction for Saharan dust effect on satellite sea surface temperature measurements. J. Geophys. Res., 97: 3611-3619 https://doi.org/10.1029/91JC02987
  11. McClain, E. P., W. G. Pichel, and C. C. Walton, 1985. Comparative performance of AVHRRbased multichannel sea surface temperature. J. Geophys. Res., 90: 11,587-11,601 https://doi.org/10.1029/JC090iC06p11587
  12. McClatchey, R. A., R. W. Fenn, J. E. Selby, F. E. Volz, and J. S. Garing, 1972. Optical properties of the atmosphere 3rd edition. Air Force Cambridge Research Laboratories, Report AFCRL-72-0497: 110
  13. Nakajima, T. and M. Tanaka, 1986. Matrix formulations for the transfer of solar radiation in a plane-parallel scattering atmosphere. J. Quant. Spectrosc. Radiat. Transfer, 35: 13-21 https://doi.org/10.1016/0022-4073(86)90088-9
  14. Nakajima, T. and M. Tanaka, 1988. Algorithms for radiative intensity calculations in moderately thick atmospheres using a truncation approximation. J. Quant. Spectrosc. Radiat. Transfer, 40: 51-69 https://doi.org/10.1016/0022-4073(88)90031-3
  15. Nakajima, T., G. Tonna, R. Rao, P. Boi, Y. Kaufman, and B. Holben, 1996. Use of sky brightness measurements from ground for remote sensing of particulate polydispersion. Appl. Opt., 35: 2672-2686 https://doi.org/10.1364/AO.35.002672
  16. Nalli, N. R. and L. L. Stowe, 2002. Aerosol correction for remotely sensed sea surface temperatures from the National Oceanic and Atmospheric Administration advanced very high resolution radiometer. J. Geophys. Res., 107: 3172-3199 https://doi.org/10.1029/2001JC001162
  17. Walton, C. C., W. G. Pichel, J. F. Sapper, and D. A. May, 1998. The development and operational application of nonlinear Algorithms for the measurement of sea surface temperatures with the NOAA polar-orbiting environmental satellites. J. Geophys. Res., 103: 27999-28012 https://doi.org/10.1029/98JC02370
  18. Wiscombe, W. J., 1980. Improved Mie scattering algorithms. Appl. Opt., 19: 1505-1510 https://doi.org/10.1364/AO.19.001505
  19. Zavody, A. M., C. T. Mutlow, and D. T. Llewellyn- Jones, 1995. A radiative transfer model for sea surface temperature retrieval for the alongtrack scanning radiometer. J. Geophys. Res., 100: 937-952 https://doi.org/10.1029/94JC02170