No evidence for a deglacial intermediate water Δ14C anomaly in the SW Atlantic

摘要: Abstract The last deglaciation was characterized by an increase in atmospheric pCO 2 and decrease radiocarbon activity. One hypothesis is that these changes were due to out-gassing of 14 C-depleted carbon from the abyssal ocean. Reconstructions foraminiferal Δ C eastern tropical Pacific, Arabian Sea, high latitude North Atlantic show severe depletions occurred at intermediate water depths during deglaciation. It has been suggested abyss upwelled Southern Ocean then carried Antarctic Intermediate Water (AAIW) sites. However, locations South Pacific direct path modern-day AAIW do not exhibit excursion therefore cast doubt upon mechanism ( De Pol-Holz et al., 2010; Rose 2010 ). Here we evaluate whether or a deglacial anomaly Southwest Atlantic. We find benthic trend our site similar trend. Our results are also largely consistent with U/Th-dated corals shallower on Brazil Margin (Mangini 2010). no evidence southwestern ~ 300‰ 18 14 kyr BP like observed Marchitto 2007 When paired those it appears did carry highly signal Another source apparently required explain intermediate-depth anomalies Atlantic, Indian, Oceans.