Intercomparison of Dobson Ozone Spectrophotometer in Yonsei University, Korea

Koji MIYAGAWA, Jhoon Kim* and Hi Ku Cho*

*Yonsei University, Korea

Abstract

　　　At Yonsei University in Korea, the ozone observation using Dobson ozone spectrophotometer is the 20th year since the commencement in 1984. The international ozone workshop (Joint International Workshop on Ozone and ILAS-II Science Team Meeting), which commemorated the 20th anniversary of ozone observation in Korea, was held at Yonsei University in November 2004. Associating with the workshop, Yonsei University performed the instrument calibration of Dobson No.124 for maintaining the measurement accuracy of ozone observation. The intercomparison of Dobson in Seoul was the first trial performed by shipping the traveling reference Dobson calibrated by the Asian regional standard No.116 in Japan. The Dobson No.124 is maintained at Global Environment Laboratory, Yonsei University and the result of ozone observation is reported to the World Ozone and Ultraviolet Radiation Data Centre (WOUDC). In the Dobson intercomparison at Yonsei University, comparison measurements, instrument maintenance, in-depth lamp tests, and the technical study were carried out during the two weeks. Finally, the Dobson No.124 was adjusted to an accuracy of less than 1 percent in total ozone comparing with the traveling reference. As in this case in Korea, on-site Dobson calibration by traveling reference instrument and the expert avoids possible characteristic shift of the comparison instrument due to transportation. Additional merits are the best-suited technical advice offered through the survey on the site environment, personnel, operation practice and data handling, as well as the information sharing of the latest technology among the participants. The practical discussion and strategy in accordance with the needs of the site is the key to successful station updating.