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.)

-