Identification

Title

Diatom Silica Oxygen Isotope Records from the Late Quaternary Antarctic Margin (NERC lead grant NE/G004811/1, child grant NE/G00413)

Abstract

Antarctica and its ice sheets have played, and continue to play, a major role in the global ocean-atmosphere system, hence, it is critical that we have a sound understanding of the past behaviour of Antarctica and it's ice sheets with a view to understanding their potential future variability under a warming climate. The Southern Ocean is a key component of the thermohaline circulation of the world's oceans and the re-distribution of heat and salt around the oceans is integral to processes that regulate rapid climate transitions. Computer modelling results have shown that sufficient melt water input to the Antarctic continental shelf area is capable of shutting down the formation of cold, salty deep water in Antarctica hence upsetting the balance of the thermohaline circulation and the ocean-climate system of the Northern Hemisphere. In order to further investigate these processes that originate in Antarctica, it is necessary to understand the transfer mechanisms of ocean-climate signals from the Antarctic ice sheets, across the continental margin seas, into the Southern Ocean. Exceptionally well-preserved Antarctic margin sediment cores, recovered during the last decade, contain an excellent archive of these ice-ocean-climate interactions, often on seasonal timescales, from the end of the last ice age and throughout the recent warm interglacial (the Holocene). The cores are seasonally layered through the deglaication, intermittently layered through the Holocene, and the layers are dominated by fossil planktonic diatoms (algae); individual species of which are sensitive to sea surface conditions including sea ice concentration, fresh water influx, and open ocean influence upon the margin. Following the last ice age, these Holocene Antarctic sediments record climate fluctuations of tens to thousands of years long and whatever environmental forcing mechanism is responsible for these fluctuations, the changes are likely to be felt in the Antarctic coastal regions first, and the cores proposed for this research are located in prime positions to record these changes. Diatom oxygen isotope measurements represent an under-utilised technique that provides a means of obtaining oxygen isotope records in high latitude environments. The measurement of oxygen isotopes in diatoms is a widely used proxy in the study of the history of lakes, however, to date there have been many fewer attempts to use records of diatom oxygen isotopes in the oceans. Studies that have taken place have demonstrated the sensitivity of diatom oxyegn isotope measurements in polar and sub-polar waters to changes in surface ocean environmental parameters such as salinity, freshwater input and sea surface temperature. The research proposed here will be the first attempt to produce diatom oxygen isotope records from the Antarctic margin, a region sensitive to the waxing and waning of the Antarctic ice sheets in terms of melt water through-put to the Southern Ocean. We propose to investigate the evolution of seasonality along the Antarctic margin since the last ice age, and also the processes involved in producing the sediment record, by relating diatom oxygen isotope measurements on season-specific diatom taxa (i.e. diatom species that thrived particularly in spring or autumn) to relative freshwater influx to the coast, from either melted terrestrial ice or sea ice. We also hope to show that the diatom oxygen isotope measurements will be low at the end of the last ice age, as a large quantity of old ice sheets were melting, and will be higher during warmer time periods of the Holocene when ice sheets were at a minimum.

Resource type

dataset

Resource locator

http://www.sciencedirect.com/science/article/pii/S0012821X12007029

function: information

http://www.nature.com/ngeo/journal/v6/n3/full/ngeo1703.html

function: information

http://eprints.nottingham.ac.uk/2017/1/laminations_v7_oa.pdf

function: information

https://www.bgs.ac.uk/services/ngdc/accessions/index.html#item44429

function: download

Unique resource identifier

code

http://data.bgs.ac.uk/id/dataHolding/13606900

codeSpace

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

Additional information source

Split award, NERC lead grant NE/G004811/1, child grant NE/G004137/1

Classification of spatial data and services

Topic category

geoscientificInformation

Keywords

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

publication

effective date

2008-06-01

Keyword set

keyword value

Holocene

Antarctic regions

Land ice

Climate change

Glacial period

Glaciation

NGDC Deposited Data

Oxygen isotopes

originating controlled vocabulary

title

reference date

date type

revision

effective date

2022

Keyword set

keyword value

Keyword set

keyword value

NERC_DDC

Geographic location

West bounding longitude

-64.2200

East bounding longitude

-64.2000

North bounding latitude

-64.8500

South bounding latitude

-64.8700

Extent

Extent group

authority code

title

reference date

date type

creation

effective date

1979

code identifying the extent

ANTARCTICA [id=880000]

Temporal reference

Temporal extent

Begin position

2009-03

End position

2012-03

Dataset reference date

date type

creation

effective date

2016-02-01

Frequency of update

notApplicable

Quality and validity

Lineage

For lineage information see published papers, http://www.nature.com/ngeo/journal/v6/n3/full/ngeo1703.html and http://www.sciencedirect.com/science/article/pii/S0012821X12007029

Conformity

Conformity report

specification

title

reference date

date type

publication

effective date

2011

degree

false

explanation

See the referenced specification

Conformity report

specification

title

reference date

date type

publication

effective date

2010-12-08

degree

false

explanation

See http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2010:323:0011:0102:EN:PDF

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Limitations on public access

Constraint set

Limitations on public access

The copyright of materials derived from the British Geological Survey's work is vested in the Natural Environment Research Council [NERC]. No part of this work may be reproduced or transmitted in any form or by any means, or stored in a retrieval system of any nature, without the prior permission of the copyright holder, via the BGS Intellectual Property Rights Manager. Use by customers of information provided by the BGS, is at the customer's own risk. In view of the disparate sources of information at BGS's disposal, including such material donated to BGS, that BGS accepts in good faith as being accurate, the Natural Environment Research Council (NERC) gives no warranty, expressed or implied, as to the quality or accuracy of the information supplied, or to the information's suitability for any use. NERC/BGS accepts no liability whatever in respect of loss, damage, injury or other occurence however caused.

Responsible organisations

Responsible party

organisation name

University of Nottingham

full postal address

School of Geography

Nottingham

NG7 2RD

United Kingdom

email address

not available

responsible party role

principalInvestigator

Responsible party

organisation name

British Geological Survey

full postal address

Environmental Science Centre, Nicker Hill, Keyworth

NOTTINGHAM

NG12 5GG

United Kingdom

telephone number

0115 936 3143

facsimile number

0115 936 3276

email address

enquiries@bgs.ac.uk

responsible party role

distributor

Responsible party

organisation name

British Geological Survey

full postal address

Environmental Science Centre, Nicker Hill, Keyworth

NOTTINGHAM

NG12 5GG

United Kingdom

telephone number

0115 936 3143

facsimile number

0115 936 3276

email address

enquiries@bgs.ac.uk

responsible party role

pointOfContact

Responsible party

organisation name

British Geological Survey

full postal address

Environmental Science Centre, Nicker Hill, Keyworth

NOTTINGHAM

NG12 5GG

United Kingdom

telephone number

0115 936 3143

facsimile number

0115 936 3276

email address

enquiries@bgs.ac.uk

responsible party role

principalInvestigator

Metadata on metadata

Metadata point of contact

organisation name

British Geological Survey

full postal address

Environmental Science Centre,Keyworth

NOTTINGHAM

NG12 5GG

United Kingdom

telephone number

+44 115 936 3100

email address

enquiries@bgs.ac.uk

responsible party role

pointOfContact

Metadata date

2024-04-11

Metadata language