Isotopically depleted carbon in the mid-depth South Atlantic during the last deglaciation

摘要: [1] The initial rise in atmospheric CO2 during the last deglaciation was likely driven by input of carbon from a 13C-depleted reservoir. Here we show that high resolution benthic foraminiferal records mid-depth Brazil Margin display an abrupt drop δ13C Heinrich Stadial 1 (HS1) is similar to but larger than atmosphere. Comparing results published North Atlantic, are unable account for South Atlantic data with conservative mixing between northern and southern component water masses. Rapid abyssal Southeast could deglacial anomalies at it would require reversal deep flow direction compared today. A new mass may explain HS1 values both contrasting oxygen isotopic two basins do not support such scenario. Instead, appears behaved non-conservatively deglaciation, possibly reflecting isotopically depleted source.