Open AccessThe Holocene CO 2 rise: Anthropogenic or natural?
Author(s) -
Broecker Wallace S.,
Stocker Thomas F.
Publication year - 2006
Publication title -
eos, transactions american geophysical union
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.316
H-Index - 86
eISSN - 2324-9250
pISSN - 0096-3941
DOI - 10.1029/2006eo030002
Subject(s) - atmosphere (unit) , glacial period , holocene , natural (archaeology) , period (music) , carbon dioxide in earth's atmosphere , carbon dioxide , physical geography , environmental science , atmospheric sciences , chemistry , geology , geography , meteorology , archaeology , paleontology , physics , organic chemistry , acoustics
In view of the wide attention received by the suggestion that the rise in atmospheric carbon dioxide (CO 2 ) over the last 8000 years is anthropogenic rather than natural in origin [ Ruddiman , 2003], this claim should be carefully examined.The basis for the claim is that following each of the three preceding glacial terminations, the CO 2 content of the atmosphere peaked early on and then underwent a steady decline. By contrast, following the end of the last glacial period, while it also peaked early the decline bottomed out around 8000 years ago, and since then the atmospheric CO 2 content has steadily risen. By analogy with previous interglaciations, Ruddiman estimates that in the absence of human activity, the CO 2 content of the atmosphere would have dropped to 240 ppm. Instead it has risen to 280 ppm. In a recent article, Ruddiman [2005] proposes that this 40 ppm human‐induced rise prevented the onset of another ice age.