How evidence from the past can help unravel the future: using palaeo-science to understand climate...

8/8/2019 How evidence from the past can help unravel the future: using palaeo-science to understand climate change in Aus

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Aknwegements

Edited b Sarah Tennant1, Karen Pearce1, Chris Turne2 and Katherine Hare3

This document is based on Building a future on knowledge from the past: what palaeo-science can revealabout climate change and its potential impacts in Australia, a scientic report prepared or the Department oCimate Change. The u report, incuding a comprehensie reerence ist o the scientic papers cited, can

be obtained at www.cimatechange.go.au

The scientic report was prepared b CSIRO in association with scientic coaborators:Katherine Hare3, Daid Etheridge3, Mike Barbetti4, Roger Jones3, Brendan Brooke5, Penn Whetton3, Tas anOmmen6, Ian Goodwin7 and Simon Habere8

With specia thanks or their assistance to:Tim Barrows8, John Chappe8, Patrick De Deckker8, Daid Fink9, Mike Gagan8, Henk Heijnis9 Ann HendersonSeers9, Pau Hesse10, Geo Hope8, Peter Kershaw11, Neie Nichos12 and Kein Henness3

1 Austraian Cimate Change Science Programme2 GeoQuEST Research Centre, Uniersit o Woongong3

CSIRO4 Uniersit o Queensand5 Geoscience Austraia6 Austraian Antarctic Diision & ACE CRC7 Uniersit o Newcaste8 Austraian Nationa Uniersit9 Austraian Nucear Science and Technoog Organisation10 Macquarie Uniersit11 Monash Uniersit12 Bureau o Meteoroog

Pubished b the Department o Cimate Change

Commonweath o Austraia, 2008

ISBN - 13: 978-1-921297-04-5

ISBN - 10: 1-921297-04-2

This work is copright. It ma be reproduced in whoe or in part or stud or training purposes subject tothe incusion o an acknowedgment o the source, but not or commercia usage or sae. Reproduction

or purposes other than those isted aboe requires the written permission o the Department o CimateChange. Requests and inquiries concerning reproduction and rights shoud be addressed to:

Director, Pubic AairsDepartment o Cimate ChangeGPO Bo 854CANBERRA ACT 2601

Coer photo: Austraian Institute o Marine Science.

Designed b ROAR (DEH 3863)


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HOW EvIDENCE FROM THE PAST CAN HElP UNRAvEl THE FUTURE

TABlE OF CONTENTS

Exeute Summary ___________________________________________________________________________2An ntrutn t paae-rers______________________________________________________________3

What are paaeo-records? _________________________________________________________________3

Wh do we need paaeo-records? __________________________________________________________3

Scaes o eidence ________________________________________________________________________4

Dating paaeo-records ____________________________________________________________________5

Wh are Austraias paaeo-records so important? _____________________________________________7

Paae-rers n Austraa_____________________________________________________________________8

Terrestria records ________________________________________________________________________8

Tree rings ____________________________________________________________________________8

Cae deposits_________________________________________________________________________9

Wetand sediments ____________________________________________________________________9

Rier, ake and dune geomorphoog ___________________________________________________10

Coasta sediments ____________________________________________________________________11

Gacia deposits ______________________________________________________________________12

Marine records__________________________________________________________________________12

Coras_______________________________________________________________________________12

Ocean sediments_____________________________________________________________________13

Antarctic records ________________________________________________________________________14

What an paae-rers te us abut ur past mate? ________________________________________16

Understanding natura cimate ariation ____________________________________________________16

Eidence o past changes in temperature, precipitation and other cimatic actors________________16

The eects o past cimate ariation on high-impact eents ___________________________________17

What an paae-rers te us abut ur uture mate?_______________________________________18

Improing cimate modes________________________________________________________________18

Predicting uture cimate driers___________________________________________________________18

Greenhouse gases ____________________________________________________________________18

Aerosos, soar and and use____________________________________________________________19

Impact o cimate change on our enironment ______________________________________________19

Understanding carbon sinks ______________________________________________________________19

The uture paae-researh n Austraa______________________________________________________21

Gssary_____________________________________________________________________________________22

Ntes ______________________________________________________________________________________22

Department o Cimate Change 1


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ExECUTIvE SUMMARy

Cimate eaes an imprint on the panet in the chemica and phsica structure o its oceans, ie and and. Inmuch the same wa that archaeoogists reea past cutures b ooking at arteacts, or detecties reconstruct acrime b piecing together eidence ound at the scene, scientists gather eidence stored in the enironment toreconstruct the histor o Earths cimate oer hundreds o thousands and in some cases miions o ears.

When combined with obserations o Earths modern cimate, eidence rom the past can hep us understandour present cimate and predict what uture cimates might be ike.

In Austraia, high quait instrumenta cimate records on etend back to the ate 19th centur, proiding justa brie snapshot o our cimates natura state and its ariabiit. To understand the nature o our present cimateand, in turn, predict our uture cimate we need data that go back ar beond the instrumenta record. This iswhere paaeo-science comes in.

Paaeo-science proides the means to etend cimate records back tens to thousands o ears. Paaeo (meaning

ancient) records incude direct and indirect (pro) eidence o past atmospheric, terrestria and marineconditions. The records are deried direct rom the enironment itse, rather than rom historica documentsand instrumenta measurements. This eidence is wide ranging, incuding andscape eatures (such as ancientake shoreines), and bioogica, chemica and isotopic materia stored in sediments, ice sheets, tree rings, caedeposits and coras. Paaeo-records proide a poweru too or reconstructing not on past cimates, but asothe driers o cimate change (incuding atmospheric concentrations o greenhouse gases), and the impactsthat cimate change has had on the enironment.

We now hae the geographic coerage and tempora resoutionrom paaeo-records to identi and understand cces o cimate

Paaeo-records proide us ariation and change across the Austraasian region that are notwith the means to understand eident in the instrumenta records. This presents an opportunit to

test and improe not on our understanding o cimate change and

the degree to which current ariabiit in Austraia, but aso the processes driing cimate change.cimate change is due to This knowedge in turn can be used to test the abiit o modes tonatura cces and human simuate cimate, improing that abiit o scientists to predict uture

cimatic conditions. Paaeo-records proide the ength o recordsinfuences. necessar or testing cimate modes that instrumenta records are

simp too short to proide.

Important, paaeo-records proide us with the means to understand the degree to which current cimatechange is due to natura cces and to human infuences. Critica to this has been the measurement ogreenhouse gases trapped in air bubbes in ice sheets (especia rom Antarctica and Greenand). This directeidence o atmospheric composition (a ke drier in cimate change) has aowed scientists to determine theariation in atmospheric greenhouse gases oer the ast 700,000 ears, demonstrating cear that the currentconcentrations are not on we aboe natura ees but that the are aso accumuating at aster rates.Simiar, paaeo-records hae been used to identi the roes that aeroso concentrations, soar irradiance andand coer change hae had in cimate orcing, both pre and post-industria times (~1750 AD).

The inormation proided b paaeo-research is inauabe in heping epain how and wh our cimatehas changed in the past and, utimate, in heping us to assess and pan or cimate change in the uture.Surrounded b oceans, Austraias ocation in the Southern Hemisphere puts us in a unique position tocontribute to the goba understanding o cimate change. There has recent been a push to bring togetherthe growing number o paaeo-records to carr out cross-regiona, nationa scae anases to importantgeographica and chronoogica gaps in the cimate record. This woud aow the production o an Austraiandata set to ria that o the Northern Hemisphere, proiding auabe inormation o past cimate ariation inthe Austraian region.

This oeriew is an introduction to the aue o paaeo-science in the understanding o cimate change in

Austraia. It is based on a technica report prepared or the Department o Cimate Change b CSIRO inassociation with coaborators rom other scientic institutions. The technica report shoud be reerred to ora comprehensie anasis o the potentia o paaeo-science to contribute to understanding cimate change in

Austraia.

Department o Cimate Change2


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USING PAlAEO-SCIENCE TO UNDERSTAND ClIMATE CHANGE IN AUSTRAlIAUSING PAlAEO-SCIENCE TO UNDERSTAND ClIMATE CHANGE IN AUSTRAlIA

AN INTRODUCTION TO PAlAEO-RECORDS

What are palaeo-records?The term paaeo comes rom the Greek word paaios, meaning ancient. Paaeo-records are natura archieso past atmospheric, terrestria and marine enironments.

Paaeo-records can be deried rom a wide range o natura sources, incuding: tree rings cae deposits (e.g. staagmites and staactites) corasAntarctic ice cores ake and marine sediments andscape eatures, such as ancient ake shores, rier courses and desert sand dunes coasta deposits (e.g. sand dunes and beach ridges) gacia deposits.

The records proide either indirect (pro) eidence o natura enironments, such as ossis or chemicasburied in sediments at the bottom o the oceans, or direct eidence, such as the gases trapped in air bubbesin ice sheets.

Some paaeo-records, such as those deried rom tree rings, cae deposits, coras, Antarctic ice cores andsediments, proide continuous records o past enironments that aow inestigation o changes rom anannua to miennia scae. Other records, such as sand dunes and coasta and gacia deposits, are notcontinuous but proide records o specic eents and periods.

Why do we need palaeo-records?

In Austraia, high quait instrumenta cimate records on etend back to the ate 19th centur. The canon proide a brie snapshot (around 100 ears) o our cimates natura state and its ariabiit. Naturacces o cimate ariabiit and change, howeer, span periods much onger than this ranging romsub-decada (e.g. E Nio-Southern Osciation cces) to hundreds and thousands o ears. There is asoeidence to suggest that these cces interact, with short-term cces being infuenced b onger termariabiit and change. To proper understand our compe cimate sstem it is necessar to acquire datathat go back ar beond the instrumenta record. Paaeo-science proides the means to do this.

Paaeo-records proide direct and pro eidence o natura cimate change and ariabiit spanningthousands o ears (Tabe 1). Important, the aso proide inormation about the processes driing ourcimate sstems and about the impacts that cimate change and ariabiit hae on the natura enironment.This means that paaeo-records can proide us with the inormation to reconstruct how our cimate sstemshae behaed through time in response to ke driers (such as changes in the composition o atmospheric

greenhouse gases) and how the natura enironment has responded to these changes.

In using paaeo-records it is important to understand that each tpe o paaeo-record has its strengths andimitations. For eampe, paaeo-records deried rom marine sediments can proide eidence o cimatechange spanning hundreds o thousands o ears, howeer, the requent ack the detai to identi annuaor een decada cimate patterns. In contrast, past cimate records obtained rom tree rings proide eidenceon annua timescaes, but are genera imited to a ew thousand ears.

To proper understand our compecimate sstem it is necessar to

acquire data that go back ar beondthe instrumenta record.



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Comparing historic records o cimate with paaeo-recordsproides an important means or identiing the degree towhich recent cimate change has been caused b naturacimate driers or b human actiities. For eampe, thecimate record oer the past thousand ears cear showsthat goba temperatures hae increased signicant inthe 20th centur, and that this warming is unprecedentedin the ast 1,200 ears. Aong with other paaeo-records,measurements o greenhouse gas concentrations coected

rom ice cores are heping to unrae how much o thiswarming can be epained b natura causes and how muchis due to human infuences.

As we as heping us to understand the behaiour o ourcimate in the past and present, the eidence deried rompaaeo-records can hep us predict uture cimate change.Understanding the driers aecting our cimate sstems isan important part o this. Paaeo-data can aso be used toaidate cimate modes - our ke too or predicting uturecimate change. B comparing simuations o past cimatechange with obserations rom paaeo-records we are abeto increase our condence in the abiit o cimate modes tosimuate uture cimate change.

Scales o evidenceThe paaeo-cimate records that are current aaiabe in the

Austraian region coer a range o scaes in time and space(see Tabe 1).

The range o spatia scaes is imited b the ocation oenironments suitabe or paaeo-records to orm, such as

the presence o suitabe cae deposits and moister cimates or wetands and bogs.

The timescaes coered b paaeo-records range rom the seasona through to the miennia. Coras, treerings and some coasta Antarctic ice cores hae proided records showing seasona changes. The hae asoproduced records spanning decades and een miennia, as hae some terrestria sediment archies.

Other paaeo-records, both on and and in the ocean,can on proide onger-term records. This is in part

due to inadequacies in the samping technique or the dating resoution, but in man cases is due to thenature o the record itse.

In Australia, high quality instrumental climaterecords only extend back to the late 19th century.



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REcoRd ScAlE PRovidES EvidENcE of

Seasonal

Decadal/subdecadal

Millennial

Temperature

Precipitation

Eaporation

Windstrength

Greenhousegases

vegetation&fre

Hydrology

Icevolume

Sedimentbudget

Seasurace

temperature

Oceancirculation

Sealeel

coNTiNUoUS

Antart e res 3 3 3 3 3 3 3 3 3 3 3cras 3 3 3 3 3 3 3 3 3 3Tree rngs 3 3 3 3 3 3 3 3cae epsts 3 3 3 3 3 3 3Marne sements 3 3 3 3 3 3 3 3 3 3Wetan sements 3 3 3 3 3 3 3 3diScoNTiNUoUS

casta epsts 3 3 3 3 3Rer, ake & unegemrphgy

3 3 3 3 3 3 3 3Gaa epsts 3 3 3 3

Table 1: Summary o the types o evidence palaeo-records can provide about past climates and climate change impacts.

With recent adances in sampe coection, dating and anasis, it is now possibe to produce high resoution,high quait records capabe o etending our cimate records considerab beond the instrumenta records.

Athough some geographica gaps eist or ke periods, the range o paaeo-records aaiabe means thatwe are now in a position to compare eidence or past cimate change and ariabiit both across the

Austraasian region and goba. This wi signicant improe our understanding o the Earths cimatesstem.

Dating palaeo-recordsProiding an age ramework or paaeo-records using dating techniques is essentia to our abiit to usepaaeo-records to understand the processes, driers and cces o past cimate change and ariabiit.

Standard dating techniques used in Austraia are based on: the deca o radioactie eements the accumuation oer time o trapped eectrons time-dependent chemica reactions the counting o annua aers, such as in trees and coras.

large widespread eents, such as ocanic eruptions or radioactie testing, can aso be used as time markers to hep date records.

The most common dating methods used in Austraia are shown in Tabe 2.



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Meth Age range Materas t whh t s appe

1. Raate eay

Radiocarbon (14C) 0-40 ka (possib60 ka under ideaconditions)

wood, resin, charcoa, peat, she,cora, bone, organic sediments

long-ied cosmogenic radioisotopes:berium-10 (10Be), auminium-26 (26A) andchorine-36 (36C)

10 ka to 10 Ma eposure age dating o rocks

Uranium-thorium disequiibrium (238U/230Th) 0-250 ka Cora, speeothems, eggshe, cosed-sstem organic sediments (such aspeats), bone

2. Trappe eetrns

Optica stimuated uminescence (OSl) 0 to 100-500 ka quartz or edspar sedimentsThermo-uminescence (Tl) 0 to 100-500 ka quartz or edspar sediments, oess,

potter, hearths, tephras

Eectron spin resonance (ESR) 0-1 Ma Cora, teeth, cacite, gpsum

3. Sw hema reatns

Amino-acid racemisation

0 to 100-500 ka Eggshe, shes, orams, wood

4. layer untng Annua(sometimesseasona)

Tree rings, cora growth rings, icecores, aminated sediments(the atter are rare in Austraia)

ka = thousand ears ago, Ma = miion ears ago

Table 2: Quaternary dating methods used in Australia1.

Radiocarbon dating is one o the techniques used to date palaeo-records. Thisphoto shows carbon dating equipment in the Adelaide laboratories o CSIROLand and Water. CSIRO Photo: Willem van Aken



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Why are Australias palaeo-records so important?Austraia spans a range o cimatic zones and so is in a unique position to proide paaeo-records o past

cimate change across a range o enironments, incuding:Antarctic temperate arid/semi-arid subtropica tropica oceanic continenta.

These records can then be compared to proide a hoistic picture o past cimate change.

Due to our ocation surrounded b seera major oceanic and atmospheric contros, Austraias paaeorecords aso proide inormation on a range o cimate-infuencing actors incuding:

the West Pacic Warm Poo the Indian Ocean Dipoe the E Nio-Southern Osciation (ENSO) tropica monsoon fow mid-atitude westeries Southern Ocean circuation.

Fina, sites in the Austraian region proide auabe data about cimate change and cimate change impactson a goba scae, or eampe:

ice cores proide auabe inormation about changes in greenhouse gas concentrations tree rings can be used to epore changes in the goba carbon budget coras and microossis in marine enironments hep reconstruct past sea ee changes.

Oera, Austraia is in a unique position to contribute to a regiona and goba understanding o how cimatesstems hae operated and how shits in goba cimate sstems hae impacted on our regiona cimates inthe past.

Austraia is in a unique position tocontribute to a regiona and gobaunderstanding o how cimate sstemsoperated in the past.



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PAlAEO-RECORDS IN AUSTRAlIA

Terrestrial recordsAustraia is ortunate in that it has not been aected b widespread gaciations, which are responsibe ordestroing much o the eidence or past enironments in arge areas o the Northern Hemisphere. Athoughthe ariet, continuit and resoution o man Austraian terrestria records hae been aected b the aridnature o much o the continent and b sow rates o sedimentation, a wide range o eidence does eistwhich can proide us with auabe insights into past cimates and cimatic processes.

Tree rings

Since tree growth is infuenced b cimatic conditions, patterns in tree ring widths, densit and chemicacomposition refect ariations in the cimate. In temperate regions, where there is a distinct growing season,

trees genera produce one ring a ear. This proides an annua record o cimatic conditions. Trees cangrow to be hundreds, een thousands, o ears od and can proide inormation about the enironment andcimate conditions at both annua and seasona scaes. This stud o tree rings is caed dendrochronoog.

Athough most Austraian tree species do not produce consistent annua rings, tree rings rom some specieshae been used to:

inestigate cimate change and cimate ariabiit oer the ast 10,000 ears coect inormation about changes in atmospheric CO

2ees

estabish reationships between cimatic ariabes and atmospheric and and surace processes.The current range o continuousdendrochronoogica records is in the order o7,000 to 10,000 ears. The ongest and most

comprehensie records in Austraia hae beenobtained using communities o Huon pine(Lagarostrobos franklinii), a ong-ied speciesendemic to Tasmania. To date, pubished tree ringrecords rom this species etend back continuous3,700 ears, athough there are oder records whichhae et to be paced in a proper, continuous time

rame. This incudes ossiised ogs beieed to bemore than 38,000 ears od.

Other species which are being inestigated ortheir paaeo-cimate record potentia incude snowgums, Bue Mountains ash, Austraian red cedar, and

northern rainorest pine trees (such as Araucaria).

The main imitation o tree ring studies is thatnot a tree species are suitabe, and with the bestspecimens genera being ound in ecoogicamargina areas, there are restrictions to the spatia

coerage o tree ring records.

Department o Cimate Change

Tree rings are clearly visible on this snow gum sample.Photo: Matthew Brookhouse

The huon pine (here interspersed with eucalypts) hasprovided records up to 3,700 years old. CSIRO

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Cave deposits

As water runs through the ground it picks up mineras

such as cacium carbonate. When minera-rich waterdrips into caes, it eaes behind soid mineradeposits which accumuate as icice-ike rocks thathang rom the ceiing (staactites) and roundedcoumns that grow rom the foor (staagmites). Thesedeposits are coectie termed speeothems.

Whie the water fows, the speeothems grow in thinaers, recording the enironmenta conditions atthe time o deposition. The amount o growth is anindicator o how much ground water has enteredthe cae sstem. litte growth might indicate adrought, just as rapid growth coud point to hea

precipitation.

Cimate records can aso be determined rom thechemica composition o the speeothems. Foreampe:

Anasis o ogen isotopes in a speeothem record rom eastern Austraia has proided an eceentreconstruction o past ENSO ariation.

Carbon isotopes hae proided records o past cimate and enironmenta conditions, incudingchanges in the reatie abundance o certain pants in the cae area.

Carbon isotope anaysis has aso determined changes in the concentration of atmospheric CO2

throughtime.

Cave deposits, such as the ones in this photo, can indicate

how much ground water has entered the cave system.Photo: Pauline Treble

Cae deposits grow in thin aers...itte growth coud indicate a droughtwhie rapid growth coud point tohea precipitation.

Depending on the samping and anasis techniques used,Austraian speeothems hae proided records o annua toseasona resoution or periods throughout the ast 200,000

ears. As et, no continuous records spanning the entire timerame hae been obtained.

Speeothem records do hae imitations. Geographica,

the records are restricted to those areas containing suitabecae deposits. Caibrating speeothem records has aso beenprobematic in the past, athough research has begun toeri paaeo-cimatic records against nearb instrumentarecords. Additiona, the reationship between the chemicasignature and cimate can oten be compe to interpret.Neertheess, much progress has been made in Austraia inthis ed o paaeo-research.

Wetland sediments

The moist, ow ogen enironments in which ake,

swamp and bog sediments are deposited are idea orthe preseration o a range o ossis incuding poen,charcoa and anima remains. These sediments aso store

Taking a terrestrial core rom Lynchs Crater,Atherton Tableland, north-east Queensland.Photo: Chris Turney.



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Wetland environments are ideal or the preservation o a rangeo ossils. CSIRO. Photo: Robert Kerton

chemica, isotopic and phsica signatures oenironmenta change.

Anasis o sediment cores etracted romthese enironments proides a weath o proeidence o past cimate change, incudingimpacts on egetation, re regimes and akehdroog. Sediment cores can aso proideauabe inormation about the main driers ocimate change and cimate ariabiit oer arange o time rames, rom ess than a decadeto hundreds o thousands o ears. New coringequipment and improed dating technooghas made it possibe to obtain high resoutionrecords rom these enironments, which can beinked to instrumenta cimate records, teing usmuch about cimate change and ariabiit oerthe ast ew centuries.

The main disadantage o wetand sedimentrecords is that the are spatia biased towardsthe moister cimates o Austraia, principa

ound in the temperate and sub-tropic regionso southern, eastern and northern Austraia.

Aso, as sedimentation rates in Austraia aregenera ow, these records can on proideinormation about ong changes in our cimate.The interaction o mutipe cimatic and

enironmenta actors in producing these sediments aso makes the interpretation o the cimatic signascompicated.

Paaeo-records rom wetand sediments hae been used to proide eidence o:

changes in the water ees o wetand enironments in response to changes in raina and eaporation changes in the temperature o ake waters in response to changes in air temperature changes in egetation tpe and, in turn, moisture aaiabiit (raina and eaporation) and

temperature changes in re regimes in response to changes in egetation and cimate changes through time in patterns o cimate ariabiit and the impact o this on oca and regiona

enironments.

River, lake and dune geomorphology

Eidence o the past etent and nature o akes, riers and dunes in Austraia can proide auabeinormation about past changes in the water baance o catchments. In particuar, it can proide inormationabout past moisture aaiabiit, sea ee change, wind strength and wind direction.

The remnants o ancient riers ound in the andscape gie eidence o past rier fows under dierentcimatic regimes. For eampe, the shape, size and sedimentar composition o ancient rier channes, suchas those eident on the Rierine Pain o NSW, hae been used to proide data on the rates and oumeo fow and in turn pro eidence o past changes in raina. Ancient rier terraces hae aso proidedeidence o periods where ground water ees changed in response to changes in sea ee2.

Eidence o the past etent o riers, akes

and dunes can proide inormation aboutpast moisture aaiabiit, sea ee change,wind strength and wind direction.



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Simiar, ancient ake shoreines aow us to reconstructchanges in ake ees in response to past cimateariabiit and change. B ooking at the buid-up osediments around these ancient akes, it is aso possibeto reconstruct past changes in wind direction and windstrength.

Eidence or the moement o dune eds acts as apro record o past periods o aridit and can proideauabe inormation about changes in wind speed anddirection. In some cases, dune deposits are interspersedwith ake and rier deposits, proiding a detaiedrecord o wet and dr phases.

B dating these changes, scientists hae a betterpicture o the timing and impacts o past cimate

ariabiit and change and the driers o these. Foreampe, studies o ancient riers, akes and duneshae been used to reconstruct:

the timing of major wet phases in arid andtemperate Austraia

past ariabiit in the precipitation/eaporation baance

past shits in the circuation o the atmosphere.These records, b their er nature, tend to beintermittent and o coarse resoution. In addition,the response o riers, akes and dunes to changesin cimate is compe and not eas to interpret. For

eampe, eidence o greater rier fows coud be asimpe response to increased precipitation or it mightbe as the resut o a compe interaction betweena range o actors incuding depositiona processes,precipitation, eaporation and nearb egetation coer.

A urther imitation o these records is their geographica bias. The ake sites, or eampe, tend to becustered in the southern and eastern regions o Austraia, whie the dune eidence has a cear arid-zonebias. Neertheess, these records, particuar when taken in combination, can proide a poweru hdroogicrecord o past cimates in Austraia.

Coastal sediments

Austraian coasta sediments hae much to te us about the nature and impacts o past cimate processesand change in areas that are current high popuated. O particuar importance are beach ridges andcoasta dunes.

Beach ridges are ormed when waes and oshore winds moe sediments, orming ridges parae to theshore. These proide useu records o the character and rate o beach sediment accumuation and o theconguration o the coast under past cimates and atmospheric circuation regimes. Sediments within thesedeposits aso proide a record o past sea ee and the passage, requenc and magnitude o past stormeents such as ccones.

Coasta dunes record the deier o sand to beach sstems b onshore winds. These deposits can proiderecords o shoreine deposition and coasta andscape instabiit as we as ancient wind regimes and, in turn,atmospheric circuation. Successions o dune deposits, such as those on the Coorong coasta pain o South

Austraia, can proide ong-term (oer seera hundred thousand ears) records o dune mobiit and ongquiescent periods when soi horizons were ormed.

Remnants o ancient dune system at Lake Mungo, northeast o Mildura in New South Wales. CSIRO.Photo: John Coppi.



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The great adantage o these records is the can proide a reatie detaied histor o coastaenironmenta change oer tens to thousands o ears. The disadantage is that the proide noncontinuous records o cimate change.

Glacial deposits

Gacia deposits in the highand regions o mainand south-eastern Austraia and Tasmania proide eidenceo cimates during past ice ages, contributing to the understanding o past processes and driers o cimatechange.

The anasis o gacia and inter-gacia deposits has proided estimates o past temperatures and rainaduring gacia periods, such as the ast ice age. This has improed our understanding o the regionahdroog o south-eastern Austraia during ice ages and the response o the enironment to signicantcoder cimates.

The most signicant imitation o Austraian gacia deposits is their restricted distribution and discontinuousnature. Additiona, uncertainties associated with dating and the combined roe o raina and temperaturein gacier ormation can compicate the interpretation o the eidence. The strength o these andscape

eatures, howeer, is that the are one o the ew pro indicators o temperature in a andscape dominatedb the eects o changes in moisture.

Marine recordsCorals

Coras hae hard, cacium carbonate skeetons that orm in seasona and annua bands. These bands containphsica, isotopic and geochemica eidence o past atmospheric and oceanic conditions at annua and sub-annua resoution.

Phsica characteristics o the bands (such as skeeta densit, tissue thickness and cacication rate) proidetime-series inormation about the enironmenta conditions that controed cora growth, such as sea suracetemperature.

Measurement o stabe isotopes and the geochemistr in coras can proide inormation about sea suracetemperature, sea surace sainit and the hdroogica baance o oceans. In regions where the isotopiccomposition o seawater correates with precipitation, cora records can aso be used to reconstructprecipitation.

luminescent banding ound in coras has been used to proide a pro or precipitation and rier run-orom adjacent and masses. It has aso been used in the identication o the moement o ocean suracewaters3,4.

Austraian scientists are at the oreront o cora research, using high quait records gathered rom aroundAustraia and the adjacent oceans to reconstruct:

past changes in cimate ariabiit moement o ocean waters ocean-atmospheric interactions atmospheric orcing o abrupt cimate change the impact o cimate change on Austraian rier sstems.

Coras are wide distributed in tropica regions and can be accurate dated, potentia proidingcontinuous records that span centuries. Data etending back thousands o ears can be obtained boerapping records.

Care must be taken when interpreting cora records to take into account biases associated with actors suchas the eposure o cora suraces to shaower water depths, aecting temperature, sainit and ight intensit

ees. This has potentia ramications or the isotopic and geochemica records obtained. Cross-matchingcora records rom dierent ocations and with instrumenta records heps to identi such errors.



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Ocean sediments

Sediments deposited in ocean and ake basins each

ear contain a ariet o eidence or past cimaticconditions, incuding microossis (ossis o tinmarine organisms), and geochemica and isotopicsignatures. Anases o the tpes and abundanceo ossi species, their chemica and isotopiccomposition, and o the chemica compositiono the sediments themsees proide eidence ochanges in past:

ocean circuation ocean productiit sea surace temperatures sea surace sainit

sea ees goba ice oume.

Marine cores can aso capture inormation romadjacent terrestria enironments. For eampe:

The poen and charcoa contained withinmarine cores rom around Austraia haeproided eidence o shits in egetationand re regimes in response to cimatic

fuctuations.variations in the dust content o cores

rom the Tasman Sea hae been used toreconstruct past changes in aridit, wind

direction and eocit oer the Austraiancontinent.

Deep sea sediment cores are particuar auabe,and can be used to piece together past gobaand regiona changes in oceanic and cimaticconditions. The are wide distributed, can becorreated across arge distances, and proide someo the ongest, most continuous records o pastcimates.

The major drawback o marine cores is thatsedimentation rates are genera ow, imiting highresoution anases.

Drilling coral cores. Photos: Australian Institute o MarineScience, Eric Matson



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Analysis o air bubbles in ice cores provides ameans or identiying changes in atmosphericcomposition.

Antarctic recordsThere is increasing eidence that the cimate o the southern high atitudes, in particuar Antarctica, is

cose inked to the goba cimate sstem. Paaeo-records rom Antarctica are thereore ita important inunderstanding the mechanisms o goba cimate change, incuding the infuence o human actiities.

Ice sheets are natura time capsues, presering records o hundreds o thousands o ears o past cimatechange, ariabiit and atmospheric composition. Each ear, aers o snow a oer the ice sheets inGreenand and Antarctica, trapping a weath o inormation about the cimatic and atmospheric conditions.

Depending on snowa rates, ice records can coerrecent decades in great detai or etend back hundreds othousands o ears. The ongest records hae been obtained

rom the centra regions o Antarctica and Greenand. Samperesoutions on these onger cores tend to be air coarse in the order o tens o ears or more arge due to thecompaction o ice at these great depths. Howeer, shorterice cores etracted rom the coasta areas o Antarctica arecapabe o proiding much higher resoutions (up to twoweeks). The trade-o, howeer, is that such cores tend tospan much shorter time periods, genera o the order oon 400 ears.

Ice cores can proide an annua record o temperature,precipitation, atmospheric composition, ocanic actiit, andwind patterns. For eampe, the thickness o each annuaaer tes how much snow accumuated at that ocationduring the ear, proiding pro eidence o precipitationchanges, as we as an understanding o past changes inthe ice sheet mass-baance. This in turn can be used to

reconstruct past sea ee ariations. Anases o fuctuations in the isotope content in ice cores hae beenused to reconstruct changes in surace air temperatures oer Antarctica and surrounding oceans throughtime, as we as the changes in ice oume. Eidence or changes in ice oume has in turn been used toreconstruct changes in sea ees through time. In addition, dierences in cores taken rom the same areacan reea oca wind patterns b showing where the snow drited. This in turn can be used to reconstructchanges in atmospheric circuation.

The aeroso content o Antarctic ice cores has asobeen a auabe source o inormation about pastcimate change and impacts. Aerosos are nepartices suspended in the atmosphere, and the

Ice sheets are natura time capsues incude:

continenta dust emissions rom ocanic eruptions human-created suphate and soot rom biomass

burning.

Some o the ice core aeroso studies that hae been carried hae detected eidence o:

changes in the etent o sea ice, conditions in the surrounding ocean, atmospheric circuation andprecipitation oer Antarctica and Austraia through anasis o changes in sodium concentrations,arge produced b sea sat rom the oceans surrounding Antarctica

continenta aridit, wind strength and trajectories, and indirect, precipitation through anasis o dustcontent

bioogica productiit through time, which can be reated to past cimatic changes and sea ice etent,through anasis o biogenic suphur tracers.



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Ice cores provide a wealth o palaeo-climaticinormation. Photos: Vin Morgan, AGAD Commonwealth o Australia

Ice cores aso proide some o the ew direct records ocimate change, in particuar the past concentrations oatmospheric gases. As snow accumuates and is compressedin ice sheets, tin air bubbes are trapped and presered.These air bubbes contain, amongst other things, a directrecord o the concentrations o atmospheric gases (such asgreenhouse gases) at the time o deposition. Anasis o theseair bubbes proides the means or identiing changes inatmospheric composition oer thousands o ears.

Indeed, Antarctic records are thought to proide the mostreiabe, ong-term eidence o changes in goba atmosphericcarbon dioide and methane through time. From ice coreswe hae been abe to identi that the ees o greenhousegases in our atmosphere oer the ast 50 ears ar eceedsan natura ees oer at east the ast 700,000 ears. Inaddition, anasis o the isotopic composition o greenhousegases contained in these ice cores has proided auabeinormation about the source o the greenhouse gases oreampe, whether methane has been deried rom burningo orests or o ossi ues.

Such records hae not on improed our understanding othe reationships between atmospheric gases and cimatebut hae aso proided us with the means o pacing recentchanges in atmospheric gas composition and cimate changein the contet o natura ariabiit.

A ke strength o Antarctic ice cores is that the proide

eidence o Southern Hemisphere cimates, as we asatmospheric and oceanic conditions oer ong timescaes andat a high resoution (annua to seasona). In particuar, theproide records o past enironments where other records,such as tree rings, cannot be gathered.

The main imitation o ice core data is that interpretationo some proies can oten be compe and subject to bias.For eampe, the reationship between snow chemistr andatmospheric concentrations has not et been u determined

or aerosos and reactie gases.



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WHAT CAN PAlAEO-RECORDS TEll US ABOUT OUR PAST ClIMATE?

Austraian instrumenta cimate records, which genera etend back to the ate 19th centur, gie eidenceo an Austraia-wide warming trend since the 1950s.

From the instrumenta record we know that Austraias mean annua maimum temperatures hae increasedb 0.06C/decade and mean minimum temperatures b 0.12C/decade oer the period 1910 to 2004. Shitsin raina hae been ess spatia consistent, athough there has been a genera trend or hotter droughts.

Cimate mode simuations indicate that the warming is ike to hae been caused b both natura ariabiitand the enhanced greenhouse eect. To unrae how much o the 20th centur warming can be epainedb natura causes and how much b human infuences, we need to eamine our cimate oer a ongertimerame than the instrumenta record aows, and use paaeo-records.

Understanding natural climate variationOer the course o the Earths histor there hae been seera major gaciation periods consisting o mutipeadances and retreats o ice eds. Each adance (an ice age) and retreat (an inter-gacia period) isbased on natura cces due to changes in the Earths orbit or the intensit o the sun. So ar in our currentgaciation period we hae had around 15-20 indiidua adances and subsequent retreats o the ice ed. Weare present in an inter-gacia period.

Paaeo-cimatic records show us that the Earthscimate is awas changing across a range o scaes,

rom decada to miennia. long continuousrecords obtained rom ice cores, marine sedimentsPaaeo-cimate records how usand ake sediments gie eidence o the interaction

that the Earths cimate is awaso cimate cces at arious scaes, ranging romchanging across a range o scaes. 1,500-ear to 100,000-ear cimatic cces. Theaso proide eidence o ong-term cimate trends,such as the trend to increasing aridit in Austraiaoer the ast 350,000 ears.

B comparing records rom dierent regions it is possibe to identi spatia ariation and test whether thesechanges were snchronous across Austraia. This not on aows us to assess the degree to which obseredchanges can be epained b natura processes, but aso improes our understanding o the reatie eects ooca and goba cimate driers.

Evidence o past changes in temperature, precipitation and other

climatic actorsAustraian paaeo-records hae proided considerabe eidence o past ariations in temperature andprecipitation. In recent ears, there has been a push to bring together the growing number o paaeorecords in order to carr out cross-regiona, nationa scae anases to produce a data set or the SouthernHemisphere. This data set wi proide auabe inormation o past ariation in cimate parameters in the

Austraian region.

For eampe:

Annua records o sea surace temperature or regions around northern and western Austraia haebeen deried rom cora records. Integration o these records with other paaeo-records proides amore compete picture o past cimates as we as inormation about regiona ariation.

A quantitatie reconstruction o past temperature and precipitation oer the ast 200,000 ears hasbeen deried rom a ong poen record rom western victoria. This reconstruction epores changes inboth mean and seasona temperature as we as precipitation change, incuding raina seasonait.

The identication o a reationship between sodium deier to Antarctica and atmospheric circuationhas produced a 700-ear pro o the Southern Annuar Mode (SAM) o cimate ariabiit. This recordis now being used to mode past southern Austraian raina ariabiit.



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The eects o past climate variation on high impact eventsAs the geographic coerage, time resoution and detai o paaeo-cimate records hae improed, it has

become possibe to identi the eects o past cimate ariations on high impact eents such as re, drought,storms, foods and sea ee rise. For eampe:

Eidence o past re regimes has been predominant deried rom charcoa records etracted romterrestria wetand sites and near-coasta marine cores.

Both drought and food eents associated with ENSO ariabiit hae been inerred rom cora recordsobtained rom the Great Barrier Ree.

Work conducted on storm deposits at Curacoa Isand o the coast o north Queensand has proided apaaeo-record o tropica ccone requenc oer the ast 5,000 ears, suggesting that storm requencin this region has remained broad constant oer this period and has been unaected b ariation insea surace temperatures.

Antarctic ice cores, cora terraces and beach deposits hae been used not on to reconstruct sea eechanges rom around the gobe, but aso to epain the causes o these changes.

Palaeo-records have provided evidence o past fre regimes.

CSIRO. Photo: Barbara McKaige



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WHAT CAN PAlAEO-RECORDS TEll US ABOUT OUR FUTURE ClIMATE?

Improving climate modelsInormation obtained rom paaeo-records wi utimate improe the abiit o modes to accurate projectthe u range o uture cimates at both regiona and goba scaes. This inormation incudes:

the degree o natura cimatic ariabiit on onger timescaes the behaiour o ke processes in the goba cimate sstem ike ENSO trends in specic cimatic parameters, such as raina in south-west Western Austraia the changing infuence o dierent driers o our cimate sstem, incuding greenhouse gases.

Paaeo-data is important to eauate the capacit o goba cimate modes to simuate past cimatic change.Demonstrating that a cimate mode can simuate cimate and cimate ariabiit oer onger timescaesbuids condence in the abiit o modes to project uture cimates.

As cimate modeing utiises an epanding range o Earth sstem processes (incuding egetation, and use,atmospheric chemistr, hdroog, ocean and and dnamic eatures, and ice sheet dnamics) a broaderrange o paaeo-data wi be needed.

Predicting uture climate driversGreenhouse gases

An understanding o the causes o past greenhouse gas changes, and their reationship with cimate, isessentia or determining the range o ike concentrations in the uture and their subsequent impact on thecimate sstem.

Precise measurements o atmospheric carbon dioide began in 1957, with ees o some haogenatedcompounds (such as perfuorocarbons, aso known as PFCs) and isotopes o nitrous oide on beingrecorded oer the past decade. These obserationa records are ar too short to eamine natura ariations,so etension into the past using paaeo-records is necessar.

The measurement o air encosed in ice sheets is the best and most direct wa o reconstructing atmospheric

The measurement o air encosedin ice sheets is the best and mostdirect wa o reconstructingatmospheric gas compositionoer the past 500,000 ears.

gas composition oer the past 500,000 ears andproides a baseine that contemporar ees can becompared with.

Austraian research in ong-term greenhouse gaschanges has great beneted rom anasing icecores rom Antarctica. A combination o outstandingice quait with unique age resoution and eadingair measurement techniques has resuted in the most

precise and detaied greenhouse gas records o thepast 1,000 ears.

The records coer a period that is being intensestudied or eidence o human-induced cimatechange. Isotopic measurement conrms that

the growth in atmospheric carbon dioide concentrations is rom ossi organic sources, consistent withthe combustion o ossi ues. The potentia or identiing the source o other gases through isotopicmeasurement is promising and wi benet rom emerging measurement technoogies which enabe theanasis o etreme sma sampe sizes.

Een or greenhouse gases or which past concentrations are we known, projecting uture concentrationsremains dicut due to natura, technoogica and economic infuences. Howeer, the paaeo-record can

great improe our understanding o the eects o natura ariation and cimate eedbacks on greenhousegas ees in the atmosphere.



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Aerosols, solar irradiance and land use

Athough greenhouse gas increases hae had the argest impact on our cimate since pre-industria times,

changes in aerosos, soar irradiance and and coer hae aso aected our cimate. When actored intocimate modes, these orcings great improe the abiit o modes to simuate temperatures oer the pasthundreds o ears.

As aerosos hae a short ie span their infuence on our cimate can ar great in both time and space. Therefectiit o the partices (oten reerred to as abedo) must aso be taken into account. The direct andindirect eects o aerosos remain uncertain.

Paaeo-records o regiona dust accumuations during periods o arge cimate changes are aso aaiabe. Aconnection between minera dust and carbon dioide concentrations in ice cores during gacia times hasbeen used to estimate the iron ertiisation eect on the uptake o carbon dioide b oceans. Aerosos in icecores aso proide we dated ong-term records o changes in the aeroso content o our atmosphere.

Soar infuences on our cimate, incuding changes in soar irradiance (the energ output o the sun) and

the shape o the Earths orbit, ar in time. Measurements o the atmospheric production rates o isotopesberium-10 and carbon-14 can be used as pro indicators o soar actiit. These isotopes are presered inice and tree ring records.

Paaeo-obserations o the Earth sstem hae substantia enhanced our understanding o the roe thebiosphere (in particuar the egetation-snow-abedo eedback) pas in ong-term cimatic changes. Thisunderstanding has subsequent improed the abiit o cimate modes to reproduce obsered cimatechanges.

Oer the ast ew centuries, the intensit and scae o and coer changes hae increased signicant. It isestimated that oer 45 percent o the Earths surace is current aected b human-induced and coermodication, which is beieed to impact on the goba cimate. There is strong eidence that and coerchanges can infuence oca to regiona scae cimate at ees equiaent to a doubing o atmosphericcarbon dioide.

Impact o climate change on our environmentThe majorit o paaeo-records, b their er nature, proide direct eidence o the impact o cimateariation on fora, auna, water resources and andscape processes. learning how the enironmentresponded to past cimate changes is the most accurate wa o predicting the combined impacts o cimatechange in the uture, or eampe:

Eamining poen, charcoa and tree ring records gies an insight to the eect o past cimatechange and ariabiit on the Austraian fora (and, indirect, auna).

Microossi records rom akes and the oceans proide inormation on how aquatic auna (reshwaterand marine) responded to shits in cimatic conditions.

Cora cores gie eidence o how coras hae responded to changes in sea surace temperature, seasurace sainit and rier run-o.

Paaeo-ake and rier records proide an insight to the combined eects o changes in precipitation,temperature and eaporation on water sources.

Paaeo-rier sequences proide eidence o erosion with high sediment oads interpreted as erosioneents associated with increased raina and possib the interaction o aridit, raina and egetation.

Dust records proide auabe inormation about the infuence o cimate on erosion. For instance, dustcontained in marine records in the Tasman Sea has been used to reconstruct the scae o wind erosion

rom the Austraian continent under dierent cimate regimes.

Understanding carbon sinksThe oceans and the terrestria biosphere hae been identied as the most important sinks o carbon dioide,

howeer there is sti debate and uncertaint oer the eact degree o echange between the atmosphereand terrestria carbon reseroirs.



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It is wide accepted that the main contro o atmospheric carbon dioide concentrations are processesoperating within the oceans, which incude:

changes in sea surace temperature and sainit (the soubiit pump) the supp and remoa o tota carbon dioide (the bioogica pump) akainit o surace waters (the akainit pump) surace winds ariations in sea ice coer.

Paaeo-records enabe the reconstruction o how these driers o oceanic-atmospheric carbon dioideechange hae operated in the past. For eampe:

Chemica anasis o marine cores has proided an insight into the operation o the bioogica pump inthe Southern Ocean during signicant changes to our cimate.

Tree ring studies hae identied an apparent shut-down o the fu o carbon dioide rom the oceaninto the atmosphere during E Nio eents.

Paaeo-records asoindicate fuctuations inatmospheric carbon underdierent cimate regimesand, important, aowus to inestigate pastinteractions betweencarbon sinks and theatmosphere.

Ice core eidence showssignicant fuctuationsin atmospheric carbon

dioide ees in responseto the onset o gacia andinter-gacia periods. Theseees tpica increasedbetween 80 and 100ppm as cimates becamewarmer in the transitions

rom gacia to inter-gaciaperiods.

Eidence o carbon ccing oer the ast ew hundred ears using modeing o ice core data shows how theterrestria biosphere has changed rom a carbon source to a sink in more recent decades. Natura cimaticariations, oten connected with ENSO, hae aso infuenced terrestria carbon dioide uptake. Records

indicate the ocean has been a sink o carbon dioide throughout most o the past 200 ears. How theAustraian terrestria carbon sinks wi respond to increasing carbon dioide in the uture is a new area ouncertaint in uture Austraian cimate change scenarios.

Records indicate the ocean has been a sink o carbon dioxide throughout mosto the past 200 years.



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THE FUTURE OF PAlAEO-RESEARCH IN AUSTRAlIA

In recent ears there has been signicant progress in deeoping more sophisticated and higher resoutionpaaeo-cimate records. These adances are opening up eciting opportunities to etend cimate recordsback ar beond the instrumenta records and improe our understanding o cimatic ariabiit. It wi asohep determine how cimate change aects terrestria and marine enironments. This inormation can, inturn, proide auabe input to decisions on how to pan or the impacts o uture cimate change.

Howeer, there are sti man important gaps in our knowedge o past cimates. This is particuar true orrecords which proide inormation about short-term cimate ariations. The majorit o records etend backon a ew thousand ears, so do not encompass the u range o possibe natura ariabiit. In some cases(such as with ice core and ake sediment records) there is potentia or etension considerab urther back intime.

There aso eists a distinct spatia bias in paaeo-records within the Austraian region which needs to be

oercome. This is arge a actor o site suitabiit, but is aso due to the reatie sma number oresearchers working in the Austraian region (reatie to eorts in the Northern Hemisphere).

There are man sites and aenues o paaeo-science et to be epored. More spatia inormation is requiredto hep understand the sources and sinks o greenhouse gases, whie more accurate, high-resoution datingis necessar to reea the mechanisms o past cimatic change. There is aso much to be earnt rom appingnew dating techniques to ke paaeo-records that hae aread been obtained.

At present, much o the research eort o theAustraian paaeo-science communit and itscoaborators has been ocused on the acquisition

There are man sites and o records, with on imited comparisons beingaenues o paaeo-science et undertaken. In essence, on now is there sucient

coerage to carr out muti-pro, cross-regionato be epored. comparisons and correations. Some eorts arebeing made in this area, but urther coordinationbetween researchers woud be o signicant benet.

So ar, such eorts hae arge been drien b researchers and data sets rom the Northern Hemisphere.In man cases, the Southern Hemisphere data is inadequate represented. We are now in the position tobring together the growing number o paaeo-records in order to produce a cimate reconstruction or theSouthern Hemisphere. Austraia is the on countr with the research capacit and inrastructure to eadeorts in using paaeo-data to test cimate modes or our region.

Fina, there is a need or paaeo-scientists to improe the communication with poic makers and naturaresource managers. There is signicant potentia or paaeo-records to improe our understanding o thecimate sstem and proide an insight into how our enironment wi respond to uture cimate change.

Austraia is we paced to make major contributions in the area o paaeo-science which wi utimate paa piota roe in understanding and constraining uncertainties about uture cimate change and its potentiaimpacts or Austraia.



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FURTHER READINGMore inormation is aaiabe in Building a future on knowledge from the past: what palaeo-science canrevealabout climate change and its potential impacts in Australia, a scientic report prepared or the Departmento Cimate Change.

The u report, incuding a comprehensie reerence ist o the scientic papers cited, can be obtained atwww.cimatechange.go.au.

GlOSSARy

aerosol ne iquid or soid partices in the atmosphere, e.g. dust, smog, og

albedo a measure o refectiit

carbon sink a process taking in CO2

rom the atmosphere

dendrochronology the anasis o annua tree rings

ENSO E Nio-Southern Osciation

geomorphology characteristics o andorms

glacial the cod stage o a ed cce o warm and coo periods during a majorice age (such as the Quaternar), during which gaciers adance acrossmuch o the gobe.

Indian Ocean Dipole anomaous warming and cooing o sea surace temperatures

inter-glacial the warm stage o a ed cce o warm and coo periods during a majorice age (such as the Quaternar), during which cimates ameiorates tosimiar ees to those o toda.

palaeo rom Greek paaios meaning od, ancient or prehistoric. Common usedto denote eidence o past enironments not contained in instrumenta ordocumented records (common known as historic records)

radioactive isotope a radionucide is an atom with an unstabe nuceus. The radionucideundergoes radioactie deca b emitting a gamma ra(s) and/orsubatomic partices.

radiocarbon Carbon-14

speleothem a minera deposit o cacium carbonate that precipitates rom soution ina cae. The two most common orms are staagmites (which etend up

rom a cae foor) and staactites (which etend down rom a cae roo).

stable isotope an isotope o a chemica eement which is not spontaneous radioactie

West Pacifc Warm Pool a bod o warm water etending through the waters o Sumatra, Jaa,Borneo, and New Guinea, and into the centra Pacic Ocean.

NOTES1 After Wiiams, M., D. Dunkerey, Kershaw, P., Chappe, J. (1998). Quaternary Environments. london, Arnod. p 271.

2 Wiiams, M., D. Dunkerey, Kershaw, P., Chappe, J. (1998). Quaternary Environments. london, Arnod.

3 See Hua, Q., Woodroffe, C.D., Barbetti, M., Smithers, S.G., Zoppi, U. and Fink, D. (2004). Marine reservoircorrection for the Cocos (Keeing) Isands, Indian Ocean. Radiocarbon, 46(2): 603-610.

4 Hughen, K.A., Baiie, M.G.l., Bard, E., Beck, J.W., Bertrand, C.J.H., Backwe, P.G., Buck, C.E., Burr, G.S., Cuter,K.B., Damon, P.E., Edwards, R.l., Fairbanks, R.G., Friedrich, M., Guiderson, T.P., Kromer, B., McCormac, G.,Manning, S., Ramsey, C.B., Reimer, P.J., Reimer, R.W., Remmee, S., Southon, J.R., Stuiver, M., Taamo, S., Tayor,F W ; van der Picht J and Weyhenmeyer C E (2004) MARINE04 marine radiocarbon age caibration 0-26 ca kyr

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