A bipolar perspective on past climate change

A bipolar perspective on past climate change (and expectations for information from the Third Pole)

Valérie Masson-DelmotteLaboratoire des Sciences du Climat et de l’Environnement

(CEA-CNRS-UVSQ/IPSL)Gif-sur-Yvette, France

3rd TPE Workshop, Reykjavik, Iceland – August 2011

Why study past climate change?

Huybers and Curry, Nature, 2006

• Expand the short instrumental recordsNatural climate variability« Slow » components: ocean, carbon cycle, ice sheets

• Understand the response of climate to forcingsDetection / attributionClimate feedbacksThresholds

• Natural case studies to benchmark Earth System models

Seasonal cycle

Glacial-interglacial cycles

Ice cores

ICELocal climate

AEROSOLS Regional atmospheric aerosol content:Sea salt, dust, volcanism, solar activity, pollutants…

AIRGlobal atmospheric compositionFirnification processes

Deep polar ice cores

NorthGRIP~ 125 000 yrs EDML : 140 000 yrs EDC : 800 000 yrs

European Project for Ice Coring in Antarctica (EPICA)

NEEM?

The greening of Greenland

Masson-Delmotte et al, submitted; updates from Bhatt et al, 2010 and van den Broeke et al, 2009

Greenland ice sheet mass balance

20°C

a)

b)

c)

+2.5°C/century

+4.7°C/century

Saqqaq

Independence I

Early Dorset

Independence II

Late Dorset

Norse

Thule

8

4

0

-4Gre

enla

nd

(°C

)

-8000 -6000 -4000 -2000 0 2000years A.D.

-44

-40

-36

-32

18O

(°/oo

)

120000 100000 80000 60000 40000 20000 0

years before A.D.2000

500

70°N June insolation (W

/m²)

8

4

0

-4

Greenland (°C

)

208020402000196019201880years A.D.

2001-2010

2010

last millennium

last millennium

1961-1990

a)

70°N June insolation NGRIP ice core smoothed NGRIP

stack ice core smoothed stack instrumental data

Year 2010 instrumental data MAR forced by ERA40 MAR forced by ERA-INTERIM MAR forced by ECHAM A1B

Instrumental data

Projections (A1B)

Ice core perspective : the last 10 000 years

Greenland cultures

Orbital forcing

Ice core perspective : the last 125 000 years

Masson-Delmotte et al, submitted; data from NGRIP, Nature 2004 and Vinther et al, Nature, 2009

Past, present and projected changes

126 ka (orbital forcing) 2xCO2

DJF

JJA

ann

Limited analogies between past and future climate change

IPSL climate model

Masson-Delmotte et al, Clim Past, in press

• Comparable magnitude of summer warming and feedbacks at mid to high latitudes north• Major differences in low-high latitude temperature gradients and seasonality

Global impacts of Greenland melt in climate projections

• global sea level

• Atlantic meridional overturning circulation

• negative feedback on Arctic warming

• ITCZ shifts with major impacts on monsoonprecipitation

Masson-Delmotte et al, submitted; simulations from Swingedouw et al, J. Climate, 2009Masson-Delmotte et al, submitted; data from NGRIP, Nature 2004 and Vinther et al, Nature, 2009

EPICA, Nature, 2006; Steffenson et al, Science, 2008; Capron et al, Clim. Past, 2010; Masson-Delmotte et al, PNAS, 2010

The Greenland-Antarctic bipolar seesaw

Full glacial conditions

Glacial inception

Precursors: dust from Chinese deserts, Greenland moisture origin shifts

25242322

obliquity2520151050Age (ky BP)

40x10-3200

-20

prec

essi

on

-10

-8

-6

Calcite

O

280

240

200

CO

2

1612

84

NA

87-2

2 SS

T(°

C)

3000200010000

IRD

-45

-40

-35

-30

Gre

enla

nd

600500400300

methane

10864

deut

eriu

m e

xces

s

-440-420-400-380

D

10864

deut

eriu

m e

xces

s

140135130125120115Age (ky BP)

3000200010000

IRD

2625242322

obliquity40x10-3200

-20pr

eces

sion

-10

-8

-6

Calcite

O

600500400300

methane

280

240

200

CO

2

-440-420-400-380

D

161284O

DP9

80 S

ST(°

C)

-45

-40

-35

-30G

reen

land

Masson-Delmotte et al, PNAS, 2010An Zhisheng et al, Science, 2011

Bipolar seesaw under interglacial conditions?

Antarctica T

Antarctic moisture source

Asian monsoon

Methane

CO2

N. Atlantic SST

Greenland T

Bipolar seesaw

Links between abrupt shifts in Antarctic moisture origin and monsoon

New tools for new challenges Searching for the oldest ice in Antarctica

Jouzel et al Science 2007, Loulergue et al Nature 2008, Lisiecki & Raymo Paleoceano 2005Masson-Delmotte et al, QSR, 2010; Jouzel and Masson-Delmotte, QSR, 2011

50x10-3

40302010

0Exce

ntric

ity

120010008006004002000

Age (ky BP)

24.524.023.523.022.5

Obliquity

-40x10-3-20

02040

Prec

essi

on

4.5

4.0

3.5

3.0

2.5

Benthic O-440

-420

-400

-380

D

280

240

200

CO

2

800700600500400300

CH 4

Present-day

Glacials

Interglacials

+5°C

-9°C

• Cause for the shift between 40 ky to 100 ky climatic cycles ?

• Oldest ice challenge

Towards a tri-polar perspective on climate change

• Links between « northern pull », « southern push » and monsoon

• Sequence of events between tropical,mid latitude and polar atmospheric circulation

• Response of climate to major volcanic eruptions (importance for the decadal predictability of climate)

Chunming Shi et al, Clim. Past, submitted

Towards a tri-polar perspective on climate change

• Exceptional monitoring effort for process-based understanding of the climatic drivers of precipitation isotopic composition

• Unique opportunity for a multi-archive TPE approach for reconstructing past precipitation 18O (ice cores, tree rings, lake sediments, speleothems…)

• Need of data syntheses for benchmarking climate models(CMIP5 includes paleoclimate simulations)

Yao Tandong et al, in preparation