후처리과정을 통한 CTD 관측 자료 품질 개선에 대하여 = The Improvement of CTD Data through Post Processing

다국어 초록 (Multilingual Abstract)

It is possible to obtain accurate temperature and salinity profiles of the oceans using a SBE 911plus CTD and accompanying data conversion packages. To obtain highly accurate results, CTD data needs to be carefully processed in addition to proper and regular maintenance of the CTD itself. Since the manufacturer of the CTD provides tools that are necessary for post processing, it is possible to conduct proper processing without too much effort. Some users, however, are not familiar with all of the processes
and inadvertently ignore some of these processes at the expense of data quality. To draw attention to these and other similar issues, we show how it is possible to improve data quality by utilizing a few extra processes to the standard or default data process procedures with CTD data obtained from the equatorial Eastern Pacific between 2001 and 2005, and 2007. One easy step that is often ignored in the standard data process procedure is “wild edit”, which removes abnormal values from the raw data. If those abnormal
values are not removed, the abnormality could spread vertically during subsequent processes and produce abnormal salinity in a range much wider than that of the raw data. To remove spikes in salinity profiles the “align CTD” procedure must be carried out not with the default values included in the data processing software but with a proper time constant. Only when “cell thermal mass” correction is conducted with optimal parameters, we can reduce the difference between upcast and downcast, and obtain results that can
satisfy the nominal accuracy of the CTD.

참고문헌 (Reference)

1 Sea-Bird Electronic,

2 신홍렬, "동태평양 KODOS 탐사해역에서의 물리해양환경 및 저층해류 특성" 26 (26): 341-349, 2004

3 Morision J, "The correction for thermal-lag effect in sea-bird CTD data" 11 : 1151-1164, 1994

4 Sea-Bird Electronic, "SBE 9plus CTD User's manual"

5 Sea-Bird Electronic, "SBE 11plus V2 Deck Unit User's Manual"

6 Kyung-Il Chang, "Hydrographic Structure Along 131.5˚W in the Eastern Tropical Pacific in July 2003" 26 (26): 299-309, 2004

7 Kim Y-G, "CTD data processing for CREAMS expeditions: Thermal-lag correction of sea-bird CTD" 35 (35): 192-199, 2000