Direct measurements reveal insignificant storage of anthropogenic CO 2 in the Abyssal Weddell Sea

In the northern Weddell Gyre at the prime meridian, Total TCO 2 changes in the Weddell Sea Bottom Water (WSBW) have been investigated. Following a suggestion by [ Poisson and Chen, 1987 ], the TCO 2 difference at potential temperatures of 0.2°C and −0.8°C was determined using data from 1996 and 1998. No significant difference was found to similar differences for the years 1973 and 1981 reported by Poisson and Chen. Thus, over a period of 25 years an at most minor amount of anthropogenic CO 2 has penetrated into the WSBW at this location. This suggests that this abyssal subpolar region is relatively unimportant for the storage of anthropogenic CO 2 . The same core of WSBW exhibited a marked increase of chlorofluorocarbon (CFC). For the Southern Ocean, therefore, CFCs are apparently of limited value as analogues of anthropogenic CO 2 , in contrast to some other ocean provinces.