한국농림기상학회지, 제 13권 제2호(2011) (pISSN 1229-5671, eISSN 2288-1859)
Korean Journal of Agricultural and Forest Meteorology, Vol. 13, No. 2, (2011), pp. 79~86
DOI: 10.5532/KJAFM.2011.13.2.079
ⓒ Author(s) 2014. CC Attribution 3.0 License.


적외선 영상 복사계를 이용한 산간집수역의 찬공기
배수와 온난대 형성 관측

경희대학교 생태시스템공학과

(2011년 06월 13일 접수; 2011년 06월 26일 수정; 2011년 06월 28일 수락)

Observation of the Cold-air Drainage and Thermal Belt Formation
in a Small Mountainous Watershed by Using an
Infrared Imaging Radiometer

Department of Ecosystem Engineering, Kyung Hee University, Yongin 446-701, Korea

(Received June 13, 2011; Revised June 26, 2011; Accepted June 28, 2011)

ABSTRACT
Cold-air drainage and pooling occur in most mountain valleys at night. Local climates with cold-air pooling could affect phenology and distribution of crop plants. A high resolution infrared imaging radiometer was used to visualize the cold-air drainage and thermal belt formation over a small mountainous watershed (ca. 10×5×1 km for the maximum length×width×depth). Thermal images on 640×480 pixels were scanned across the Akyang valley (south of Mt. Jiri National Park) by the radiometer installed at a local peak (‘Hyongjebong’, 1,117 m a.s.l.) at dawn of 17 May 2011, when the synoptic condition was favorable for the surface cooling and cold-air drainage. Major findings are: (1) Cold-air drainage and accumulation was clearly identified by the lowest brightness temperature mainly at the valley bottom. (2) So-called ‘thermal belt’ with higher brightness temperature was found partway up the valley sidewalls and showed up to 5oC departure from the valley bottom temperature. (3) Digital thermography showed feasibility for validation of the high definition geospatial temperature models currently in use for the plot-specific agrometeorological service.

Keyword: Cold air drainage, Cold pool, Thermal belt, Infrared imaging radiometer, Slow city akyang

MAIN

적요

산간계곡에는 특히 야간에 찬 공기가 흘러 고이는 일이 흔한데, 이런 곳의 식생은 생장과 발육이 그렇지 않은 주변지역에 비해 달라질 수 있어 관심의 대상이다. 이 연구는 작은 규모의 집수역에서 적외선 영상을 이용하여 냉기호와 온난대의 형상을 가시화 할 수 있는지 알기 위해 수행하였다. 경남 하동군 악양면 형제봉(해발 1,117m)에 적외선 영상 복사계를 설치하여 관측여건이 양호했던 2011년 5월 17일 새벽부터 일출시까지 악양계곡의 열영상을 640×480 해상도로 획득하였다. 열영상 분석결과 계곡의 바닥에 나타난 낮은 온도 분포에 의해 찬공기의 배수를 인지할 수 있었고, 계곡 양쪽 사면에서 바닥보다 5oC 높은 온난대의 실체를 확인할 수 있었다. 적외선 영상을 이용하면 기존 고해상도 디지털 기온분포도‘전자기후도’의 신뢰성 검증이 한층 수월해져서 전자기후도 실용성 확보에 도움이 될 것이다.

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