The atmospheric CO2 concentrations at Amsterdam Island (37¿41'S; 77¿47'E) from October 1980 to November 1983 showed an increase rate of 0.11 ppm/month for a 3-year average with considerable variability within each year: 0.06-0.14 ppm/month in 1981. 0.04-0.12 in 1982 and 0.13-0.25 in 1983. The natural evasion of oceanic CO2 following the 1982/1983 El Nino event could account for a part of the anomalous change.