Temporal variations of atmospheric CO2 concentration and carborn isotope ratio in Ny-Alesund, Svalbard

• Main Authors: Shinji Morimoto, Shuji Aoki, Takashi Yamanouchi
• Format: Report
• Language: English
• Published: National Institute of Polar Research 2001
• Subjects: Svalbard; Ny-Ålesund; Memoirs of National Institute of Polar Research; Ny Ålesund; Polar Research
• Online Access: https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=2361; http://id.nii.ac.jp/1291/00002361/; https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=2361&item_no=1&attribute_id=18&file_no=1

Ground based observation of the atmospheric CO_2 concentration and its carbon isotope, δ^<13>C, have been performed in Ny-Ålesund, Svalbard since 1991. The CO_2 concentration and δ^<13>C observed in 1991-1999 showed clear seasonal cycles with peak-to-peak amplitudes of 16.5‰ ppmv and 0.8,respectively. From comparison of the seasonal cycles, it was found that the seasonal CO_2 cycle in Ny-Ålesund is mainly caused by seasonal change of biospheric activities. Interannual variations of the CO_2 concentration and δ^<13>C superimposed on their secular trends were also observed. Comparing both of the interannual variations revealed that the cause was primarily ascribed to the imbalance of the CO_2 exchange between the atmosphere and the terrestrial biosphere.