Development of an Atmospheric Carbon Dioxide Standard Gas Saving System and Its Application to a Measurement at a Site in the West Siberian Forest

• Published in: Journal of atmospheric and oceanic technology Vol. 27; no. 5; pp. 843 - 855
• Main Authors: Watai, T, Machida, T, Shimoyama, K, Krasnov, O, Yamamoto, M, Inoue, G
• Format: Journal Article
• Language: English
• Published: Boston American Meteorological Society 01.05.2010
• Subjects: Amplitudes; Atmospherics; Boreal forests; Boundary layers; Carbon dioxide; Diurnal variations; Forests; Gases; Ground stations; ISO standards; Marine; Stations; Towers; Winter
• ISSN: 0739-0572; 1520-0426
• DOI: 10.1175/2009JTECHA1265.1

Abstract Observations of the atmospheric CO2 concentration from a 90-m tower in Berezorechka, western Siberia, that have taken place since October 2001 were used to characterize CO2 variations over a vast boreal forest area. A new CO2 standard gas saving system was developed that reduced the consumption of standard gases and kept the analysis precision to within 0.3 μmol mol−1. The CO2 day-to-day variation correlated well with atmospheric stability. The average amplitudes of the diurnal variation at 80 m were found to be about 17 and 1.5 μmol mol−1 in July and December 2003, respectively. Extremely high daytime CO2 concentrations of greater than 400 μmol mol−1 were occasionally observed during the winter, which were caused by anticyclonic atmospheric conditions lasting more than several days. Afternoon CO2 values observed at the 80-m height agreed to within 0.4 μmol mol−1 with aircraft CO2 measurements taken in the planetary boundary layer; disagreements were found for anticyclonic conditions in the winter. The afternoon CO2 values reached their maximum in mid-January and their minimum late in July, with the seasonal amplitude of 30.9 μmol mol−1. Compared to observations at background stations, this observation tower recorded a larger seasonal amplitude and earlier occurrence of the seasonal minimum.