Testing the control of weathering on CO2 - Evidence from extreme climate events (NERC Grant NE/I020571/2)

Dataset description

Published papers for NERC grant NE/I020571/2. Grant award abstract: How does the Earth's climate recover from events of rapid and extreme global warming or cooling? Why have the huge fluctuations in atmospheric CO2 in the geological past not caused runaway climate effects, making the Earth become Venus- or Mars-like? Silicate weathering of the continents is the main CO2 removal process, and therefore a dominant long-term climate control mechanism. However the debate on what controls silicate weathering, and therefore atmospheric CO2, is still contentious and ongoing. A correct understanding of the controls on weathering, and its link to atmospheric CO2 levels is critical, because 1) it is possible that weathering is the process that has kept Earth's climate in the relatively narrow bounds required for life over the past several hundred million years; 2) it is impossible to decipher the causes and consequences of long-term climate variations through Earth's history without accurate weathering data, which in turn impacts on our understanding of current climate; 3) comprehension of climate systems leads to more accurate modelling of future climate change; 4) rapid global climate change inevitably leads to large mass extinctions. Therefore it is important to unravel the link between extinctions and the Earth's climate systems, including CO2 control. Lithium isotopes have gained much interest over the past few years because large variations in the Li isotope ratio in rivers and clays are caused by silicate weathering processes. Furthermore, unlike tracers of weathering used previously, Li isotopes also respond to the intensity of weathering, and therefore can be linked directly to weathering rates. This is critical, because for the first time is gives us a window into the variation of weathering rates through time, which in turn means we can use the Earth's past climate variations as a natural laboratory. Three of the largest climate fluctuations and mass extinctions in Earth's history will be examined and modelled, primarily using Li isotopes, but also several other tracers, which will serve to reveal information on marine and volcanic conditions at the time. These geological periods (the end-Ordovician glaciation (450 Ma (million years ago)), the Permo-Triassic event (251 Ma) and the Cenomanian-Turonian Ocean Anoxic Event (94 Ma)), represent times when rapid warming or cooling of Earth's climate occurred, resulting in the extinction of up to 90% of life on Earth. Samples from these time periods exist in the form of marine calcium carbonate. This was precipitated (either inorganically, or via various life forms) in the oceans at the time, and provides a record of ocean chemistry, which in turn is directly linked to the atmospheric conditions. Analysing Li isotopes is a complex procedure, and will be undertaken at Oxford University. Collaborations will exist with Prof. Jan Veizer (Ottawa University) and Dr. Christoph Korte (Copenhagen University), who are specialists in the studied time periods, with Prof. Andy Ridgwell (Bristol University), who is an expert climate modeller, and with Prof. David Harper, who is an expert in mass extinctions. By understanding weathering and climatic responses to periods of rapid global warming and cooling we will gain critical information on Earth's climate feedbacks, and on processes that led to the extinction of vast proportions of the biosphere.

Constraints

Some of the published papers are open access, others are available via subscription to the relevant scientific journal.

Further information

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Enquiries

Environmental Science Centre, Nicker Hill, Keyworth
Nottingham
NG12 5GG

Tel : +44 (0)115 936 3143
Fax :+44 (0)115 936 3276
Email :enquiries@bgs.ac.uk

 

Dataset details

Author(s) Not available
Principal Investigator(s) Not available
Language English
Curator British Geological Survey
Supply media/format Not available
Storage format Not available
Frequency of update not applicable
Start of capture {ts '2016-12-01 00:00:00'} Before December 2016
End of capture {ts '2017-09-20 11:32:40'} Not known
Contact details
Department Enquiries
Organisation British Geological Survey
Address Environmental Science Centre, Nicker Hill, Keyworth
City Nottingham
County Nottinghamshire
Country United Kingdom
Postcode NG12 5GG
E-mail enquiries@bgs.ac.uk
Telephone +44 (0)115 936 3143
Fax +44 (0)115 936 3276
Keywords
Topic category code (ISO) geoscientificInformation (information pertaining to earth sciences)
Keywords CLIMATE CHANGE
CLIMATOLOGY
Keyword source BGS Keyphrases
Spatial details
Spatial Reference System Not available
Dataset extent
Coverage (Lat/Long) North boundary : 
East boundary  : 
South boundary : 
West boundary  : 
Metadata
Metadata language English
Metadata last updated 12th January 2017
Metadata standard compliance NERC profile of ISO19115:2003
Copyright and IPR
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.