Journal cover Journal topic
Earth System Dynamics An interactive open-access journal of the European Geosciences Union

Journal metrics

  • IF value: 3.635 IF 3.635
  • IF 5-year<br/> value: 3.869 IF 5-year
    3.869
  • CiteScore<br/> value: 4.15 CiteScore
    4.15
  • SNIP value: 0.995 SNIP 0.995
  • SJR value: 2.742 SJR 2.742
  • IPP value: 3.679 IPP 3.679
  • h5-index value: 21 h5-index 21
https://doi.org/10.5194/esdd-5-809-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
Research article
27 Jun 2014
Review status
This discussion paper has been under review for the journal Earth System Dynamics (ESD). A final paper in ESD is not foreseen.
Temporal variations in atmospheric CO2 on Rishiri Island in 2006–2013: responses of the interannual variation in amplitude to climate and the terrestrial sink in East Asia
C. Zhu1,* and H. Yoshikawa-Inoue2 1Graduate School of Environmental Science, Hokkaido University, Sapporo, 060-0810, Japan
2Faculty of Environmental Earth Science, Hokkaido University, Sapporo, 060-0810, Japan
*now at: Institute of Low Temperature Science, Hokkaido University, Sapporo, 060-0819, Japan
Abstract. Surface observation of the atmospheric CO2 mixing ratio implies the combined influences of both natural fluctuations and anthropogenic activities on the carbon cycle. Atmospheric CO2 has been measured on Rishiri Island in the outflow region of Eurasia since May 2006. We report the first 7 year temporal atmospheric CO2 variations from diurnal to interannual scales. In the diurnal scale, an obvious cycle appeared as a minimum in the afternoon and maximum at midnight in the summer months. Seasonally, the maximum CO2 concentration appeared around the beginning of April, while the minimum appeared around the middle of August. A mean growing season length of ~126 days was estimated. In the period from 2007 to 2012, the peak-to-peak amplitude increased until 2009 and decreased thereafter, with a mean value of 19.7 ppm. In the long term, atmospheric CO2 is increasing by a mean growth rate of 2.1 ppm year−1. Investigations on the driving climatic factors on the interannual variation in amplitude indicated that temperature in East Asia (40–60° N, 90–150° E) affected the CO2 amplitude by affecting the seasonal maximum, with a time lag of 1–2 years. On the contrary, precipitation did not likely affect CO2 amplitudes. The amplitude also responded to a natural carbon source/sink variation in East Asia. We suggest that temperature in the first year would affect carbon sinks in the second year in the fetch regions, which further affect CO2 amplitude mainly through ecosystem respiration. Circulation changes also likely contributed to the decreasing amplitude since 2009, as indicated by the simultaneous decrease in the 222Rn concentration in spring and summer.

Citation: Zhu, C. and Yoshikawa-Inoue, H.: Temporal variations in atmospheric CO2 on Rishiri Island in 2006–2013: responses of the interannual variation in amplitude to climate and the terrestrial sink in East Asia, Earth Syst. Dynam. Discuss., 5, 809-848, https://doi.org/10.5194/esdd-5-809-2014, 2014.
C. Zhu and H. Yoshikawa-Inoue
C. Zhu and H. Yoshikawa-Inoue

Viewed

Total article views: 749 (including HTML, PDF, and XML)

HTML PDF XML Total BibTeX EndNote
446 261 42 749 35 20

Views and downloads (calculated since 27 Jun 2014)

Cumulative views and downloads (calculated since 27 Jun 2014)

Saved

Discussed

Latest update: 25 Jun 2017
Publications Copernicus
Download
Share