bipolar synchroneity and latitudinal timing of holocene climate change eric a. meyerson (cci, u....
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Bipolar Synchroneity and Latitudinal Timing of Holocene Climate Change
• Eric A. Meyerson (CCI, U. Maine)• Paul A. Mayewski (CCI, U. Maine)• Sharon B. Sneed (CCI, U. Maine) • Andrei V. Kurbatov (CCI, U. Maine)• Karl J. Kreutz (CCI, U. Maine)• Greg A. Zielinski (CCI, U. Maine)• Kendrick C. Taylor (DRI)• Ed J. Brook (Wash. State U.)• Eric J. Steig (U Washington)
This project funded by the National Science Foundation’s Office of Polar Programs (Grant Number 0096305)
Amundsen Sea
Siple Dome.
Image: USGS
• Gregg Lamorey, SDM SCO (DRI)• Geoff Hargreaves and NICL• Polar Ice Coring Office• Field and CPL Team-Members• Clim. Change Res. Ctr. (UNH)• Sallie Whitlow (CCRC UNH) • IC Lab & Freezer Lab Workers• John Rhoades (NICL)• Gordon Hamilton (UMaine)• Brenda Hall (UMaine)• Yan Yuping (UMaine)
Amundsen Sea
Siple Dome.
Image: USGS
This project funded by the National Science Foundation’s Office of Polar Programs (Grant Number 0096305)
Acknowledgements
Prepared by D. Dixon (UMaine) using RAMP-DEM (Liu et al., 2000).
Hamilton, Annals of Glaciology, 35, 2002waiscores.dri.edu
Siple Dome, West Antarctica
Elevation: 621 m a.s.l.81.654°S, 148.808°W
Hamilton (2002), modified from Nereson et al. (1996)
Siple Dome A-Core
ssNa nssK
Icelandic Low (DJF)
Siberian Low (MAM)
A 1400-year high-resolution record of Atmospheric circulation over the NorthAtlantic and Asia
Meeker & Mayewski,Holocene (2002)
Sea-level pressure variability in the Amundsen Sea region inferred from a West Antarctic glaciochemical record
Kreutz, Mayewski, Pittalwala, Meeker, Twickler, WhitlowJ. Geophys. Res. (2000)
SEP OCT
NOV
ssNa(sea-salts)
nssK, nssCa(cont. dusts)
GISP2: Mayewski et al., 1997TD: Mayewski et al., 1996DC: Röthlisberger et al., 2002
GISP2: Mayewski et al., 1997TD: Mayewski et al., 1996DC: Röthlisberger et al., 2002
QuickTime™ and aYUV420 codec decompressorare needed to see this picture.
NASA/GSFC Scientific Visualization StudioScientist: B. BindschadlerAnimator: A. Kekesi
20000 to 0 years BP
Years Before Present
Å14 C Years Before Present
0 2000 4000 6000 8000 10,000 12,000
0 2000 4000 6000 8000 10,000
world wide glacialexpansionsand their relativemagnitude
synthesis ofclimate proxyrecords, showingcold periods
YD event -GISP2
Europe and Greenland
North America
Southern Hemisphere
Cockburn Moraineadvance
2
1
-1
0
GISP2 Holocene
Figure from:O’Brien et al., Science, 1995.
Polar Circulation Index (PCI)
(Denton & Karlén, 1973)
4
5
6
50
100
150
8
12
16
1
2
0
1
2
0.2
0.4
0.6
0.8
6
9
12
0
3
6
0.5
1
1.5
0 2000 4000 6000 8000 10000 12000
0
3
6
GISP2
GISP2
GISP2
SipleDome
SipleDome
SipleDome
DC
DC
TD
TD
TD
40
50
60
70
Year (before 2000 A.D.)
0 2000 4000 6000 8000 10000 12000
ssNa
nssK
nssCa
Holocene
GISP2SipleDome
TaylorDome
DC
Late-Holocene (≤ 2000 yr B2k)
ssNa
nssK
nssCa
GISP2SipleDome
TaylorDome
DC
Conclusions: Glacial-to-Holocene
-SDM displays mid- to high-latitude S. Pacific signal (ssNa)as well as Polar Plateau climate signal (nssCa)
-SDM ssNa shows rise from Early-Holocene most likely fromdominating role of ASL due to WAIS grounding line retreat inRoss Sea Embayment (Conway et al., 1999; Baroni & Hall, in review)
-ssNa reaches highest levels in most recent ~500 years, evenhigher than LGM concentrations in contrast to GISP, TD, DC
-Bipolar Synchronicity of Rapid Climate Change Events at:~6000-5000 yr BP~3000 yr BP~modern millenial (classic “LIA” time period)
Conclusions: Holocene
Conclusions: Late-Holocene
-Bi-Core Confirmation of Late-Holocene Event at Siple Dome--A-Core (this study)--1994-Core (Kreutz et al., Science, 1997)
-Bipolar Synchronicity of this modern millenial event
-Bipolar Onset Timing Differs (due to site location wrt hemispheric continents)
Evolution of Event-SD ssNa Senses Atm. Circ. 1st (~750 yr B.P.)-GISP2 Dusts & Sea-Salts (600 yr B.P.)-SD Dusts as Atm. Circ. Expands North (400 yr B.P.)
-