Keywords:Carbon dioxide, Methane, Siberia, in-situ measurement, CRDS
Continuous measurements of CO2 and CH4 concentration have been carried out using a tower network in Siberia (JR-STATION: Japan-Russia Siberian Tall Tower Inland Observation Network) to study the spatial and temporal variations of CO2 and CH4 and estimate the distribution of the flux over this vast area (Sasakawa et al., 2010, 2012, 2013) where only a few atmospheric investigations had been made. Transport of working standard gases to remote sites is a significant issue. Thus, to reduce the consumption of the gases, Watai et al. (2010) developed a system that utilizes in-situ air as sub-working standard gas to track the baseline drift of an NDIR. The calibrations using the working standard gases were carried out twice a day. Watai et al. (2010) installed the system at the first tower site in West Siberia (Berezorechka). We modified the working gas saving system and further added a CH4 sensor (Suto et al., 2010), then expanded the tower network. We evaluated the uncertainty of the concentrations obtained from this modified system. From the year of 2015, we installed a Cavity Ring-Down Spectroscopy (CRDS; Picarro inc.) at Karasevoe, Demyanskoe, and Noyabrsk. We thus validate the recent data with the data by the CRDSs.
Sasakawa, M. et al., Tellus 62B, 403-416, 2010.
Sasakawa, M. et al., Tellus 64B, doi:10.3402/tellusb.v64i0.17514, 2012.
Sasakawa, M. et al., J. Geophys. Res. 118, 1-10, doi:10.1002/jgrd.50755, 2013.
Suto, H. et al., J. Atmos. Ocean. Tech. 27, 1175-1184, 2010.
Watai, T. et al., Atmos. Ocean. Tech. 27, 843-855, 2010.