HR: 1330h
AN: A52C-0815    [PDF]
TI: Measurements of CO2 Mixing Ratio in and above PBL over the Forest Area in Western Siberia
AU: * Machida, T
EM: tmachida@nies.go.jp
AF: National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, 305-8506 Japan
AU: Krasnov, O
EM: krasnov@iao.ru
AF: Institute of Atmospheric Optics SB RAS, Akademicheskii av.1, Tomsk, 634055 Russian Federation
AU: Watai, T
EM: watai.tomonori@nies.go.jp
AF: Global Environmental Forum, 16-2 Onogawa, Tsukuba, 305-8506 Japan
AU: Shimoyama, K
EM: shimoyama.kou@nies.go.jp
AF: National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, 305-8506 Japan
AU: Inoue, G
EM: inouegen@nies.go.jp
AF: National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, 305-8506 Japan
AB: To understand the difference in CO2 variation between planetary boundary layer (PBL) and free troposphere (FT) quantitatively, we conducted CO2 measurements in high frequency using a small aircraft and a tower at the forest area in western Siberia. Continuous CO2 measurement system was installed near the radio communication tower (90 m height) located in Berezorechka village (56N, 84E) in October 2001. Small CO2 measurement device based on single-cell NDIR (LI-COR, LI-800) equipped with pressure regulation system was developed and installed in a small aircraft, An-2. Two standard gases are introduced into NDIR every 5 minutes. The aircraft ascend to 2 km above Berezorechka tower and then descend to 0.15 km to get the vertical profile of CO2. The aircraft measurement has been conducted every 1-3 weeks since February 2002. 34 vertical CO2 profiles were obtained in 2002. The height of afternoon PBL was 0.2-0.9 km in winter and 0.5-2 km in summer. The CO2 mixing ratio in PBL was 10 ppm lower in summer and 2-3 ppm higher in winter compared to that in FT aloft. The peak-to-peak amplitude of seasonal CO2 variation in PBL was 35 ppm and that in FT was 19ppm. The phase in seasonal variation is slightly earlier in PBL. The lowermost aircraft data are compared with tower data obtained in the afternoon. Both data agree well in winter. In summer lower CO2 values in the scatter of tower measurements are similar to aircraft data.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0315 Biosphere/atmosphere interactions
DE: 0365 Troposphere--composition and chemistry
SC: Atmospheric Sciences [A]
MN: 2003 Fall Meeting