TY  - JOUR
A1  - Naafs, B. David A.
A1  - Hefter, Jens
A1  - Acton, Gary
A1  - Haug, Gerald H.
A1  - Martinez-Garcia, Alfredo
A1  - Pancost, Richard
A1  - Stein, Rüdiger
T1  - Strengthening of North American dust sources during the late Pliocene (2.7 Ma)
T2  - Earth & planetary science letters
N2  - Here we present orbitally-resolved records of terrestrial higher plant leaf wax input to the North Atlantic over the last 3.5 Ma, based on the accumulation of long-chain n-alkanes and n-alkanl-1-ols at IODP Site U1313. These lipids are a major component of dust, even in remote ocean areas, and have a predominantly aeolian origin in distal marine sediments. Our results demonstrate that around 2.7 million years ago (Ma), coinciding with the intensification of the Northern Hemisphere glaciation (NHG), the aeolian input of terrestrial material to the North Atlantic increased drastically. Since then, during every glacial the aeolian input of higher plant material was up to 30 times higher than during interglacials. The close correspondence between aeolian input to the North Atlantic and other dust records indicates a globally uniform response of dust sources to Quaternary climate variability, although the amplitude of variation differs among areas. We argue that the increased aeolian input at Site U1313 during glacials is predominantly related to the episodic appearance of continental ice sheets in North America and the associated strengthening of glaciogenic dust sources. Evolutional spectral analyses of the n-alkane records were therefore used to determine the dominant astronomical forcing in North American ice sheet advances. These results demonstrate that during the early Pleistocene North American ice sheet dynamics responded predominantly to variations in obliquity (41 ka), which argues against previous suggestions of precession-related variations in Northern Hemisphere ice sheets during the early Pleistocene.
KW  - aeolian input
KW  - dust
KW  - terrestrial higher plant waxes
KW  - Milankovitch
KW  - North Atlantic
KW  - Quaternary
Y1  - 2012
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/36143
SN  - 0012-821X
SN  - 1385-013X
VL  - 317
SP  - 8
EP  - 19
PB  - Elsevier
CY  - Amsterdam
ER  -