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Partitioning of the global fossil CO 2 sink using a 19‐year trend in atmospheric O 2
Author(s) -
Langenfelds R. L.,
Francey R. J.,
Steele L. P.,
Battle M.,
Keeling R. F.,
Budd W. F.
Publication year - 1999
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/1999gl900446
Subject(s) - biosphere , environmental science , carbon dioxide , carbon dioxide in earth's atmosphere , atmospheric sciences , disequilibrium , flux (metallurgy) , isotopes of carbon , sink (geography) , geology , climate change , oceanography , geography , chemistry , environmental chemistry , total organic carbon , biology , ecology , cartography , organic chemistry , medicine , ophthalmology
O 2 /N 2 is measured in the Cape Grim Air Archive (CGAA), a suite of tanks filled with background air at Cape Grim, Tasmania (40.7°S, 144.8°E) between April 1978 and January 1997. Derived trends are compared with published O 2 /N 2 records and assessed against limits on interannual variability of net terrestrial exchanges imposed by trends of δ 13 C in CO 2 . Two old samples from 1978 and 1987 and eight from 1996/97 survive critical selection criteria and give a mean 19‐year trend in δ(O 2 /N 2 ) of −16.7±0.5 per meg yr −1 , implying net storage of +2.3 ± 0.7 GtC (10 15 g carbon) yr −1 of fossil fuel CO 2 in the oceans and +0.2 ± 0.9 GtC yr −1 in the terrestrial biosphere. The uptake terms are consistent for both O 2 /N 2 and δ 13 C tracers if the mean 13 C isotopic disequilibrium flux, combining terrestrial and oceanic contributions, is 93±15 GtC ‰ yr −1 .