EPICA deep ice core, an archive for millennial climate change Hans Oerter

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EPICA deep ice core,

an archive for millennial climate change

Hans Oerter

Alfred Wegener Institute for Polar and Marine Research, Member of Helmholtz Association, Bremerhaven, Germany

Hans.Oerter@awi.de

http://www.awi.de/People/show?hoerter

, 31.01.2006

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Introduction: EPICA

The past Glacial The Holocene

Conclusions

foto: hans oerter, 2008

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Kohnen

Dome C

Vostok Dome A Dome F

Law Dome

Talos D.

Taylor D.

Siple D.

Byrd Siple St.

Dyer Pl.

B15 Berkner Is.

South Pole

layout: w. rack, h. oerter, AWI

JARE

3029m, >700 ka

China, ^planned

I, F, D, UK Weddell Sea

Ross Sea Antarctic

peninsula EPICA-DML,

2774m, >250 ka

Deep ice-core drillings in

Antarctica

Russia,F, US

3700m, 420 ka

EPICA-DC,

3270m, 790 ka

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accumulation accumulation

Schematic cross section through an ice sheet

characteristic for

Antarctica Greenland

gr ounding line

equilibrium line ice thickness

ice thickness Mean: Mean: iceberg

calving iceberg

calving

ablation ice sheet/

inland ice

rock

ocean subglacial melting

ice shelf

accumulation

ablation

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The climatic record of the EDML ice core

Kohnen Station

75°00‘09“S, 00°04‘06“E, 2892 m (WGS84)

Annual mean air

temperature: -45 °C

Ice thickness:

2782 ±10m

Accumulation rate:

65 kg m

^-2

a

^-1

Ice flow velocity:

0.756 m/a

Length of ice core:

2774.1 m

Drilling operation:

2001-2006

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The climatic record δ ¹⁸ O

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The climatic record of the EDML ice core

Measurements of the stable isotope ¹⁸ O given as δ-values in ‰ V-SMOW

EDML ice core dated down to 2416 m with

EDML1 age scale:

150.1 ka

sample resolution:

0.5 m

corresponding to at 125 m: 6 a at 2400 m: 280 a

For the Holocene and other

selected intervals also 5cm samples available

87% ice thickness

data: EPICA Community Members (2006): One-to-one coupling of glacial climate variability in Greenland and Antarctica. Nature 444, 195-198. data:doi:10.1594/PANGAEA. 552270

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The climatic record of the EDML ice core

Data of δ ¹⁸ O plotted against time; 0.5m samples (grey) and re-sampled on 100a intervals (red)

Raw data

(AnaySeries2.0 software, Paillard et al., EOS Trans. AGU, 1996)

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The climatic record of the EDML ice core

Data of δ ¹⁸ O corrected for sea level change in the past and re-samped on 100a intervals (blue)

Raw data

sea level correction

+

(AnaySeries2.0 software, Paillard et al., EOS Trans. AGU, 1996)

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The climatic record of the EDML ice core

Data of δ ¹⁸ O corrected for elevation differences between Kohnen and site of deposition (green)

Raw data

sea level correction

+

upstream correction

0.96‰/100m

(AnaySeries2.0 software, Paillard et al., EOS Trans. AGU, 1996)

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The climatic record of the EDML ice core

Data of δ ¹⁸ O corrected for elevation differences between Kohnen and site of deposition (green/pink)

Raw data

sea level correction

+

upstream correction

0.96‰/100m 0.63‰/100m

LGM MIS 4

MIS 5.5

MIS 1 MIS 3 MIS 5

AIM 1

2 8 12 17

21 23

24 MIS 6

(AnaySeries2.0 software, Paillard et al., EOS Trans. AGU, 1996)

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The climatic record of the EDML ice core

Data of δ ¹⁸ O corrected for elevation differences between Kohnen and site of deposition (green/pink)

Raw data

sea level correction

+

upstream correction

0.96‰/100m 0.63‰/100m

-43.90‰

-41.83‰

-40.74‰

3 ka ΔH = -330m 2 ka ΔH = +100m

-50.64‰

Δδ= -0.33‰

-52.17‰

-52.50‰

Δδ=1.09‰

1 δ-‰ change equals 1.2 °C change

(AnaySeries2.0 software, Paillard et al., EOS Trans. AGU, 1996)

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The climatic record of the EDML ice core

2 time slices for millenial variability

25-50 ka 0-11.5ka

Holocene

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The past Glacial

(25-50 kyears B.P.)

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Comparison Antarctica (EDML) - Greenland (NGRIP)

Each Antarctic

Isotope Maximum (AIM) in the EDML- ice core

corresponds to a Dansgaard/

Oeschger (DO) event in Greenland (NGRIP)

Warming in

Antarctica starts in a cold phase (Stadial) of the North, Cooling in a warm phase (Interstadial)

AIM

DO

NGRIP members, Nature (2004)

NGRIP

EDML

Source: EPICA Community Members: Nature, 444, 195-198, (2006). data: doi:10.1594/PANGAEA.552235

EDML: 1 δ-‰ change equals 1.2 °C change

100a means

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The climatic record of the EDML ice core

LGM MIS 4

MIS 5.5

MIS 1 MIS 3 MIS 5

AIM 1

2 8 12 17

21 23

24 MIS 6

The bi-polar seesaw

is also evident for MIS 5 as shown by

E. Capron et al. (subm.) by synchronizing EDML and NGRIP with CH

4

&

δ

¹⁸

O

atm

for the period 80-123 ka BP.

The bi-polar seesaw is also very likely for earlier Glacials (Jouzel et al., Science 2007)

E. Capron et al.: Synchronising EDML and NorthGRIP ice cores using δ

¹⁸

O of atmospheric

oxygen (δ

¹⁸

O

atm

) and CH

4

measurements over MIS 5 (80-123 ka). submitted to Quaternary

Science Reviews

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CH 4 concentrations at EDML

CH

4

synchronous with DO events in Greeland

CH

4

signal of the

Northern Hemisphere CH

4

variations

synchronous on global scale:

tool to synchronize ice cores

Source: EPICA Community Members: Nature, 444, 195-198, (2006).

data: doi:10.1594/PANGAEA.552235 & doi:10.1594/PANGAEA.552232

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The Holocene The δ ¹⁸ O record

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EPICA EDML core

The Holocene

EPICA Community Members (2006): One-to-one coupling of glacial climate variability in Greenland and Antarctica. Nature 444, 195-198 (data: doi:10.1594/PANGAEA.552270)

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EPICA EDC core EPICA EDML core

The Holocene

EPICA Community Members (2006): One-to-one coupling of glacial climate variability in Greenland and Antarctica. Nature 444, 195-198 (data: doi:10.1594/PANGAEA.552270) Orbital and Millenial Antarctic Climate Variability over the Past 800,000 Years (2007). Science 317, 793-796 (data: http://www.ncdc.noaa.gov/paleo/icecore/antarctica/domec/

domec_epica_data.html)

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The Holocene

B32:

150m deep ice core, 1.6 km west of EDML, drilled in Dec 1997.

EPICA EDC core EPICA EDML core

EPICA Community Members (2006): One-to-one coupling of glacial climate variability in Greenland and Antarctica. Nature 444, 195-198 (data: doi:10.1594/PANGAEA.552270) Orbital and Millenial Antarctic Climate Variability over the Past 800,000 Years (2007). Science 317, 793-796 (data: http://www.ncdc.noaa.gov/paleo/icecore/antarctica/domec/

domec_epica_data.html)

Graf, W. et al. (2002). Stable-isotope records from Dronning Maud Land, Antarctica, Annals of Glaciology, 35, 195-201(data: doi:10.1594/PANGAEA.104881)

1 δ-‰ change equals 1.2 °C change

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The Holocene The CO 2 record

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Etheridge, D.M., et al. (2001): Law Dome Atmospheric CO2 Data, IGBP PAGES/World Data Center for Paleoclimatology. Data Contribution Series #2001-083. NOAA/NGDC Paleoclimatology Program, Boulder CO, USA.

Keeling, C.D., T.P. Whorf, and the Carbon Dioxide Research Group (2005): Atmospheric CO2 concentrations (ppmv) derived from in situ

air samples collected at Mauna Loa Observatory, Hawaii. Scripps Institution of Oceanography (SIO) University of California La Jolla, California USA

Siegenthaler, U., et al. (2005). Supporting evidence from the EPICA Dronning Maud Land ice core for atmospheric CO2

changes during the past millenium, Tellus, 57B, 51-57. (doi:10.1594/PANGAEA.472477)

CO 2 record during the past millenium

Time with in-situ air samples

The EDML CO

2

record is a strong support of the Law Dome record from the Antarctic

plateau

B32

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Conclusions

Upstream corrections needed

Antarctic Isotope Maxima (AIMs) are

counterparts to DO events in Greenland CH 4 synchronous with DO events

Holocene incl. past Millenium little δ ¹⁸ O variations

The EDML CO 2 record is a strong support of the

Law Dome record from the Antarctic plateau

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Thanks for your attention

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Antarctic ice core records: Vostok and EPICA CO

₂

, CH

₄

and D D

Petit et al., 1999 (Vostok), Siegenthaler et al., 2005 (Dome C - CO₂), Spahni et al., 2005 (Dome C - CH₄), EPICA community members, 2004 (DD)

180 210 240 270 300

CO

2

(ppmv)

-450 -420 -390

Cold Warm

D D ice (‰)

300 400 500 600 700

0 200 400 600 800

Age / kyr BP CH

4

(ppbv)

EPICA Dome C data Vostok (black) and Dome C (blue) data

Vostok (black) and Dome C (blue) data

EPICA data are plotted on EDC2, Vostok data on GT4 timescale

100 300 500 700

EPICA deep ice core, an archive for millennial climate change Hans Oerter