한국농림기상학회지, 제 11권 제1호(2009) (pISSN 1229-5671, eISSN 2288-1859)
Korean Journal of Agricultural and Forest Meteorology, Vol. 11, No. 1, (2009), pp. 19~26
DOI: 10.5532/KJAFM.2009.11.1.019
ⓒ Author(s) 2014. CC Attribution 3.0 License.


KoFlux 에디 공분산 자료 처리의 표준화

홍진규(1), 권효정(1), 임종환(2), 변영화(3), 이조한(3), 김 준(1)
(1)연세대학교 대기과학과/지구환경연구소,
(2)국립산림과학원 산림생태과, (3)국립기상연구소 기후연구과

(2008년 12월 27일 접수; 2009년 01월 16일 수정; 2009년 01월 23일 수락)

Standardization of KoFlux Eddy-Covariance Data Processing

Jinkyu Hong(1), Hyojung Kwon(1), Jong-Hwan Lim(2), Young-Hwa Byun(3), Johan Lee(3), Joon Kim(1)
(1)Department of Atmospheric Sciences/Global Environment Lab, Yonsei University, Seoul, Korea 120-749
(2)Korea Forest Research Institute, Department of Forest Environment
(3)National Institute of Meteorological Research, Climate Research Lab

(Received December 27, 2008; Revised January 16, 2009; Accepted January 23, 2009)

ABSTRACT
The standardization of eddy-covariance data processing is essential for the analysis and synthesis of vast amount of data being accumulated through continuous observations in various flux measurement networks. End users eventually benefit from the open and transparent standardization protocol by clear understanding of final products such as evapotranspiration and gross primary productivity. In this paper, we briefly introduced KoFlux efforts to standardize data processing methodologies and then estimated uncertainties of surface fluxes due to different processing methods. Based on our scrutiny of the data observed at Gwangneung KoFlux site, net ecosystem exchange and ecosystem respiration were sensitive to the selection of different processing methods. Gross primary production, however, was consistent within errors due to cancellation of the differences in NEE and Re, emphasizing that independent observation of ecosystem respiration is required for accurate estimates of carbon exchange. Nocturnal soil evaporation was small and thus the annually integrated evapotranspiration was not sensitive to the selection of different data processing methods. The implementation of such standardized data processing protocol to AsiaFlux will enable the establishment of consistent database for validation of models of carbon cycle, dynamic vegetation, and land-atmosphere interaction at regional scale.

Keyword: Eddy-covariance, Standardization, data processing, Uncertainty, KoFlux

MAIN

적요

연속적인 지표 플럭스 관측으로부터 축적되는 엄청난 양의 자료를 체계적으로 처리분석하고 종합하여 일관성 있는 결과를 도출해 내려면 에디 공분산 자료처리 방법의 표준화가 우선되어야 한다. 이 논문에서는 국내 타워 플럭스 관측 네트워크인 KoFlux의 표준화된 자료 처리 방법을 소개하고, 처리 방법이 다른 경우에 생길 수 있는 지표 플럭스의 불확실성을 평가하였다. 광릉 활엽수림에서 관측된 탄소 플럭스의 경우, 순생태계교환량(net ecosystem exchange, NEE)과 생태계호흡량(ecosystem respiration, Re)은 각각 자료처리 방법의 차이에 따라 민감한 반응을 보였다. 그러나 두 양이 서로 상쇄되어, 총일차생산량(gross primary productivity, GPP=NEE+Re)은 자료 처리 방법이 다른 경우에도 불구하고 오차 범위 내에서 일치하였다. 이러한 결과는 GPP를 산출할 때에 Re를 독립적으로 관측하는 것이 중요함을 시사한다. 반면 수증기 플럭스(증발산)의 경우, 야간 토양 증발이 작아서 연 적산증발산량은 자료 처리 방법에 민감하지 않았다. 이렇게 표준화된 자료처리 프로토콜을 아시아 타워 플럭스 네트워크인 AsiaFlux에 적용할 경우, 지역 규모 탄소순환, 역학 식생 및 지면과정 모형의 검증을 위한 일관성 있는 데이터베이스의 구축이 가능해 질 것이다.

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