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A Note on the Geostrophic Velocity Estimation from a AVHRR Image and its Application

AVHRR 자료를 이용한 지형류의 추정과 그 적용

  • Published : 1993.06.01

Abstract

The relative geostrophic velocity is estimated by using the MCSST(Multi-Channel Sea Surface Temperature) from a NOAA/AVHRR image and applied to the Korea Strait. Remote sensing technique can play a useful role to research for oceanic phenomena because of its synoptic, simultaneous and repetitive viewing. The high resolution data of AVHRR can determine the geostrophic flow more precisely than the hydrographic data on shipboard. As a result of research, the relative geostrophic velocity in the weatern channel of the Korea Strait is the strongest in the trough area and its maximum speed is about 23.8cm/sec in April, 1992. But this results include the error due to neglecting the effect of salinity in estimation the geopotential anomaly. The geostrophic volume transport through the western channel of the Korea Strait is the largest between trough area and the Tsushima Island.

NOAA AVHRR의 MCSST를 이용하여 지형류의 상대속도를 추정하였으며 이것을 대한 해협에 적용하였다. 원격탐사는 관측시에 광범위한 지역에 대해서 동시성 및 반복성이 유지되기 때문에 해양현상을 연구하는 데 있어서 훌륭한 도구로써 쓰일 수 있다. 특히 AVHRR 자료는 높 은 분해능으로 인해서 선상관측 자료보다도 지형류를 더욱 정밀하게 구할 수 있다. 연구 결과에 의하면 1992년 4월에 대한해협 서수도에서의 상대속도는 골이 있는 해역에서 가장 크며 이때 유 속의 크기는 약 23.8cm/sec로 나타났다. 그러나 이 결과는 geopotential anomaly를 계산할 때 염 분의 효과를 무시한 만큼의 오류를 포함하고 있다. 또한 대한해협 서수도에서 지형류의 수송량은 약 0.3Sv이며 쓰시마와 골이 있는 해역 사이에서 수송량이 가장 큰 것으로 나타났다.

Keywords

References

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