TY  - JOUR
A1  - Vogt-Vincent, Noam
A1  - Lippold, Jörg
A1  - Kaboth-Bahr, Stefanie
A1  - Blaser, Patrick
T1  - Ice-rafted debris as a source of non-conservative behaviour for the epsilon Nd palaeotracer
BT  - insights from a simple model
JF  - Geo-marine letters : an international journal of marine geology
N2  - Neodymium isotopic composition (epsilon Nd) has enjoyed widespread use as a palaeotracer, principally because it behaves quasi-conservatively in the modern ocean. However, recent bottom water epsilon Nd reconstructions from the eastern North Atlantic are difficult to interpret under assumptions of conservative behaviour. The observation that this apparent departure from conservative behaviour increases with enhanced ice-rafted debris (IRD) fluxes has resulted in the suggestion that IRD leads to the overprinting of bottom water epsilon Nd through reversible scavenging. In this study, a simple water column model successfully reproduces epsilon Nd reconstructions from the eastern North Atlantic at the Last Glacial Maximum and Heinrich Stadial 1, and demonstrates that the changes in scavenging intensity required for good model-data fit is in good agreement with changes in the observed IRD flux. Although uncertainties in model parameters preclude a more definitive conclusion, the results indicate that the suggestion of IRD as a source of non-conservative behaviour in the epsilon Nd tracer is reasonable and that further research into the fundamental chemistry underlying the marine neodymium cycle is necessary to increase confidence in assumptions of conservative epsilon Nd behaviour in the past.
KW  - Neodymium isotopes
KW  - epsilon Nd
KW  - ice-rafted debris
KW  - IRD
KW  - last glacial
KW  - maximum
KW  - LGM
KW  - Heinrich event
KW  - Palaeoceanography
KW  - Paleoceanography
KW  - model
KW  - reversible scavenging
KW  - conservative
KW  - ocean circulation
KW  - atlantic
KW  - meridional overturning circulation
KW  - geochemical cycling
Y1  - 2020
U6  - https://doi.org/10.1007/s00367-020-00643-x
SN  - 0276-0460
SN  - 1432-1157
VL  - 40
IS  - 3
SP  - 325
EP  - 340
PB  - Springer
CY  - Berlin
ER  -