Open AccessImpact of strong deep ocean stratification on the glacial carbon cycle
Author(s) -
Bouttes N.,
Roche D. M.,
Paillard D.
Publication year - 2009
Publication title -
paleoceanography
Language(s) - English
Resource type - Journals
eISSN - 1944-9186
pISSN - 0883-8305
DOI - 10.1029/2008pa001707
Subject(s) - deep sea , stratification (seeds) , carbon cycle , oceanography , glacial period , last glacial maximum , geology , climatology , holocene , environmental science , atmospheric sciences , paleontology , ecology , botany , germination , ecosystem , dormancy , biology , seed dormancy
During the Last Glacial Maximum, the climate was substantially colder and the carbon cycle was clearly different from the late Holocene. According to proxy data deep oceanic δ 13 C was very low, and the atmospheric CO 2 concentration also reduced. Several mechanisms have been proposed to explain these changes, but none can fully explain the data, especially the very low deep ocean δ 13 C values. Oceanic core data show that the deep ocean was very cold and salty, which would lead to enhanced deep ocean stratification. We show that such an enhanced stratification in the coupled climate model CLIMBER‐2 helps get very low deep oceanic δ 13 C values. Indeed the simulated δ 13 C reaches values as low as −0.8‰ in line with proxy data evidences. Moreover it increases the oceanic carbon reservoir leading to a small, yet robust, atmospheric CO 2 drop of approximately 10 ppm.