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Fig. 2 Deglacial development of the LC and the MR discharge. Left GoM SST
Mg/Ca
record of
IMAGES core MD02-2575 (ros
b
W, 847 m depth) from DeSoto Canyon
re
ecting deglacial warming of the northeastern GoM in response to the northward migrating LC
eddies (this study; N
,29
°
00.10
′
N, 87
°
07.13
′
é
rnberg et al.
2008
; Ziegler et al.
2008
) in comparison to (i) the Caribbean
SST
Mg/Ca
record of ODP Site 999 (brown,12
ü
°
45'N, 78
°
44'W, 2827 m depth, all measured on the
planktonic foraminifer G. ruber white; see N
rnberg et al.
2008
), (ii) the potassium (K) record of
IMAGES core MD02-2576 (light blue,29
ü
W, 848 m) approximating
terrigenous supply from the MR (Kujau et al.
2010
), and (iii) the Waelbroeck et al. (
2002
)
relative sea level curve (black). The stable oxygen isotope (
°
00.09
′
N, 87
°
07.14
′
18
Oin
VPDB) record of Greenland
ice core NGRIP is used for stratigraphical control (dark gray). Right Various
δ
δ
‰
18
O
ivf
−
sw
records
approximating SSS changes from the northern GoM (MD02-2575, red, this study; M78-181-1,
orange,29
°
00.00
′
N, 88
°
20.00
′
W, 803 m depth, this study; EN32-PC6, light blue,26
°
56.8
′
N,
91
°
20.0
′
W, 2280 m depth, after Flower et al.
2004
), Florida Straits (KNR166-2-26, green,
24
°
19.60
′
N, 83
°
15.40
′
W, 547 m depth, Schmidt and Lynch-Stieglitz
2011
), and Blake Outer
Ridge (ODP Site 1058, gray,31
°
41.00
′
N, 75
°
26.00
′
W, 2984 m, Bahr et al.
2013
). The blue
hatched line marks the today
'
s
δ
18
O
sw
value of the GoM (Lodico et al.
2006
). Shaded areas
indicate Heinrich Event 2 (H2), Heinrich Event 1 (H1), and the Younger Dryas (YD) cool event.
Black and open triangles denote AMS
14
C-datings at IMAGES core MD02-2575 (N
ü
rnberg et al.
2008
) and core M78-181-3 (this study), respectively
years (ka) before present (BP) (Fig.
2
) is in line with an insolation-driven southward
migration of the ITCZ, synchronous with the declining in
uence of the LC on the
GoM hydrography. The decrease in SSS in the GOM is paralleled by wetter con-
ditions over South Florida pointing to gradually increasing precipitation during the
late Holocene.
Acknowledgements This work has been
financed by the German Research Foundation (DFG) in
the framework of the SPP1266 INTERDYNAMIK and IMAGES programs. Sample material was
partly provided by the Integrated Ocean Drilling Program. The model integrations have been
performed at University Kiel and Deutsches Klimarechenzentrum (DKRZ), Hamburg.
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