Precise and continuous measurements of atmospheric CO2 concentration have been continued at Syowa Station (69°00′S, 39°35′E), Antarctica since February 1984. Diurnal CO2 variation was hardly observable throughout the year. The secular CO2 trend was variable with time, showing slow increase in 1984, 1986 and 1988 and rapid increase in 1985 and 1987. The annual CO2 increase was remarkable, especially in 1987, which may have been related to the 1987 ENSO event. The average rate of annual CO2 increase over the last 5 years was about 1.6 ppmv yr-1. The average seasonal CO2 cycle showed minimum and maximum concentrations in mid-April and in early October, respectively. Its peak-to-peak amplitude was about 1.1 ppmv for the period 1984-1988. The seasonal cycle was variable from year to year, but there was no indication of long-term amplitude increase. It was found that irregular CO2 variations with amplitudes of about 0.2 ppmv and with periods of a few tens of days have high correlation with air mass exchange by synoptic scale weather disturbances.
|Number of pages||16|
|Publication status||Published - 1996 Dec 1|
ASJC Scopus subject areas
- Aquatic Science
- Earth and Planetary Sciences(all)