Instability of the East Antartic Ice Sheet during the Pliocene warmth?
Lead Research Organisation:
Imperial College London
Department Name: Earth Science and Engineering
Abstract
Warming of the climate system is unequivocal, and evident from observations of increases in global average air and ocean temperatures. Based on projections published in the Nobel Peace Prize winning report of the Intergovernmental Panel on Climate Change in 2007, the Earth's surface is estimated to warm between 1.8 to 4.0 degree Celsius by the end of the century. Already now, we are observing the retreat of mountain glaciers, limited extent of sea ice in the Arctic Ocean, and melting around the edges of the polar ice caps in Greenland and parts of Antarctica. Projected sea level rise by 2100 ranges between 0.2 and 0.6 m. This range however does not include potential contributions from the ice caps, which today tie up a water mass equivalent to about 60-70 m of sea level change. From studying the climate in the past, we know that the polar ice caps can wax and wane with changing climatic conditions. The last time Earth climate was significantly warmer than today, for an extended amount of time, was 4.5 to 3 million years ago, during the time period of the Pliocene. Global temperatures in the warm Pliocene were about 3 degree Celsius higher than today. Sea level estimates for this time range from 5 to 40 m higher than today, with a most commonly used value around 25 m. Such an elevated sea level would not only mean the disappearance of the Greenland and West Antarctic ice sheets, but also instability in parts of the massive East Antarctic ice sheet. Data are however sparse, and models give conflicting results on whether melting only acted on the more vulnerable West Antarctic ice sheet, or also on parts of the large East Antarctic ice sheet. With our project we will try to address exactly this dilemma. We are going to analyse the chemical composition of ice-rafted sediments from the Southern Ocean off East Antarctica. This material was carried to its place of deposition by icebergs, and its geochemical fingerprint contained in mineral grains, allows us to track back the exact area of the continent where the iceberg was coming from. This in turn tells us which part of the ice margin became instable in the past. It is such evidence from the geological record that is vital to test and refine existing climate models. We will investigate which adjustments have to be made to climate models to reproduce our observational data. Once we succeed to produce a better database for understanding ice extent during the Pliocene warmth, and once we have a climate model that matches the observations of the past, we should have higher confidence to use the same type of model to foresee what may happen in the future.
Publications
Bertram R
(2018)
Pliocene deglacial event timelines and the biogeochemical response offshore Wilkes Subglacial Basin, East Antarctica
in Earth and Planetary Science Letters
Colleoni F
(2022)
Antarctic Climate Evolution
Cook C
(2014)
Sea surface temperature control on the distribution of far-traveled Southern Ocean ice-rafted detritus during the Pliocene
in Paleoceanography
Cook C
(2017)
Glacial erosion of East Antarctica in the Pliocene: A comparative study of multiple marine sediment provenance tracers
in Chemical Geology
Cook C
(2013)
Dynamic behaviour of the East Antarctic ice sheet during Pliocene warmth
in Nature Geoscience
Cox S
(2010)
Extremely low long-term erosion rates around the Gamburtsev Mountains in interior East Antarctica
in Geophysical Research Letters
Dolan A
(2011)
Sensitivity of Pliocene ice sheets to orbital forcing
in Palaeogeography, Palaeoclimatology, Palaeoecology
Levy R
(2022)
Antarctic Climate Evolution
McKay R
(2018)
Developing community-based scientific priorities and new drilling proposals in the southern Indian and southwestern Pacific oceans
in Scientific Drilling
Title | Grantham art prize |
Description | Melanie King created spinach anthotype of the B46 iceberg that calved off Pine Island Glacier in West Antarctica. |
Type Of Art | Artwork |
Year Produced | 2019 |
Impact | Great interactions with the general audience at the award ceremony and following reception. |
URL | https://www.melaniek.co.uk/pine-island-glacier#! |
Description | The project applied the innovative method of using the geochemical fingerprint of marine sediments to trace East Antarctic ice sheet stability. By combining geochemical fingerprinting of coarse (ice-rafted) and fine-grained sediments we could successfully identify the sources of detrital sediment in over 100 Pliocene samples from two main locations in the Southern Ocean (ODP Site 1165, IODP Site U1361). These data were supplemented by regional core-top analyses as well as by the development of an iceberg drift model to simulate Pliocene iceberg trajectories. Results indicate a very dynamic behaviour of the East Antarctic ice sheet during the Pliocene, which was characterised by environmental conditions similar to what what we expect to experience by the year 2100. The East Antarctic ice sheet retreated repeatedly into two large subglacial basins, the Wilkes Subglacial Basin as well as the Aurora Subglacial Basin. The retreat was probably driven by increased incursions of warm waters into low-lying areas of the continent and could have contributed significantly to sea level rise during the Pliocene. |
Exploitation Route | For a long time it was thought that the East Antarctic ice sheet has been stable since the Middle Miocene (~14 Ma). Our new data show that this was clearly not the case, and that low-lying areas of the ice sheet may be vulnerable to future melting, in a similar way to what is observed today around West Antarctica. Our results thereby challenge some of the existing ice sheet models, demanding more refined physics to allow ice sheet retreat in these areas. |
Sectors | Environment |
Description | Ice sheet modellers have taken our result aboard and revised their models to allow for ice retreat in Antarctica under Pliocene conditions, which are very similar to predicted temperature ranges for the end of this century. The new mechanisms added are now producing results that are better aligned with our reconstructions of the ice margins in the Wilkes Subglacial Basin, East Antarctica. As the same models are used for projecting future sea level rise, our work had a major societal impact. The publication of our Nature Geoscience paper in 2013 received great attention by the international media and has been cited >235 times. |
First Year Of Impact | 2013 |
Sector | Education,Environment |
Impact Types | Societal,Policy & public services |
Description | Grantham Briefing paper |
Geographic Reach | National |
Policy Influence Type | Implementation circular/rapid advice/letter to e.g. Ministry of Health |
URL | https://www.imperial.ac.uk/grantham/publications/briefing-papers/what-ancient-climates-tell-us-about... |
Description | Antarctic ice sheet history revealed by marine sediment provenance |
Amount | £9,900 (GBP) |
Funding ID | IE110878 |
Organisation | The Royal Society |
Sector | Charity/Non Profit |
Country | United Kingdom |
Start |
Description | Deglacial ice dynamics in the Weddell Sea embayment using sediment provenance |
Amount | £320,000 (GBP) |
Funding ID | ANT 1342213 |
Organisation | National Science Foundation (NSF) |
Sector | Public |
Country | United States |
Start | 10/2014 |
End | 09/2017 |
Description | History of the East Antarctic ice sheet since the mid-Miocene: new evidence from provenance of ice-rafted debris |
Amount | £215,029 (GBP) |
Funding ID | ANT 0944489 |
Organisation | National Science Foundation (NSF) |
Sector | Public |
Country | United States |
Start |
Description | Ocean-ice Interaction in the Ross Sea during Past Warm Periods |
Amount | £25,152 (GBP) |
Funding ID | NE/R018219/1 |
Organisation | Natural Environment Research Council |
Sector | Public |
Country | United Kingdom |
Start | 04/2018 |
End | 12/2019 |
Description | Reconstructing the stability of the Antarctic ice sheets |
Amount | £250,000 (GBP) |
Organisation | A Foundation |
Sector | Charity/Non Profit |
Country | United Kingdom |
Start | 10/2014 |
End | 09/2018 |
Description | Royal Society International Exchange grant |
Amount | £11,650 (GBP) |
Funding ID | IE161090 |
Organisation | The Royal Society |
Sector | Charity/Non Profit |
Country | United Kingdom |
Start | 03/2017 |
End | 02/2019 |
Description | Detrital grain thermochronology, L-DEO |
Organisation | Columbia University |
Department | Earth and Environmental Sciences |
Country | United States |
Sector | Academic/University |
PI Contribution | Geochemical provenance analyses for reconstructing past ice sheet behaviour works best if a multi-proxy approach is taken. Imperial College contributed fine-grained radiogenic isotope analyses to this project. |
Collaborator Contribution | Geochemical provenance analyses for reconstructing past ice sheet behaviour works best if a multi-proxy approach is taken. Columbia University contributed single grain Ar-Ar dates to this project at a greatly reduced cost. |
Impact | This is a long-standing collaboration going back to my own time as research fellow and research scientist at Columbia University. The results to date are ~20 publications in the peer-reviewed literature. |
Start Year | 2010 |
Description | Atmosphere exhibiton |
Form Of Engagement Activity | A formal working group, expert panel or dialogue |
Part Of Official Scheme? | Yes |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | Helped with scientific advise during the design phase of the atmosphere exhibition in the Science Museum (opened in autumn 2010). I take now every year our new first year students to the exhibition and make them present on some aspect of the atmosphere exhibition. It is well received by visitors of the museum. |
Year(s) Of Engagement Activity | 2010 |
Description | Blog from IODP expedition |
Form Of Engagement Activity | A magazine, newsletter or online publication |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | I run a blog reporting live from IODP expedition 318 to Wilkes Land, Antarctica. Many enthusiastic comments about my blog from friend, family, students, and the general public. |
Year(s) Of Engagement Activity | 2010 |
Description | Chasing Ice |
Form Of Engagement Activity | A formal working group, expert panel or dialogue |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Public/other audiences |
Results and Impact | Panelist on a screening of the documentary 'Chasing Ice' at Imperial College London. The audience was stunned by the wonderful pictures presented in this film, but also by the scientific facts revealed by it. They appreciated the presence of science experts on the topic to follow up their questions. |
Year(s) Of Engagement Activity | 2013 |
Description | EGU poster presentation 2011 |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Other academic audiences (collaborators, peers etc.) |
Results and Impact | Poster presentation at the EGU 2011 in Vienna, on 'Bulk sediment geochemistry as a tool in palaeoclimate studies; preliminary results from shipboard analyses of IODP Expedition 318' highlighting the value of shipboard bulk sediment geochemistry for preliminary interpretations. Positive comments on modification of IODP protocols for shipboard geochemistry on palaeoceanography legs. |
Year(s) Of Engagement Activity | 2011 |
Description | Earthclass |
Form Of Engagement Activity | Participation in an open day or visit at my research institution |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Schools |
Results and Impact | Annual open day event by the Department of Earth Science and Engineering to educate school kids on Earth Science topics. The children loved to see how you can take a fish tank, partnered with a bit of salty water, ice cubes and heating elements, and produce ocean circulation. |
Year(s) Of Engagement Activity | 2011,2012 |
Description | Evening lecture in Cardiff |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Regional |
Primary Audience | Public/other audiences |
Results and Impact | Sparked questions and discussion. |
Year(s) Of Engagement Activity | 2016 |
Description | Evening talk 2013 |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Public/other audiences |
Results and Impact | Evening talk on Antarctic Science at the Amateur Geological Society in London. Good follow up discussions. |
Year(s) Of Engagement Activity | 2013 |
Description | Great Exhibition Road Festival - Blast from the Past |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | Regional |
Primary Audience | Public/other audiences |
Results and Impact | The Great Exhibition Road Festival is a new three day celebration of curiosity, discovery and exploration that brings together science and the arts in the spirit of the Great Exhibition of 1851.We had a stand to bring the science done by the International Ocean Discovery Programme (IODP) closer to a general audience. From climate change, over earthquakes, to impacts that killed the dinosaurs. We had truly fantastic interactions with countless member of the public, young and old, scientifically-inclined and intrigued. The festival was visited by 60,000 people and our stand was on the main road. |
Year(s) Of Engagement Activity | 2019 |
URL | https://www.imperial.ac.uk/news/193776/great-exhibition-road-festival-2019-earns/ |
Description | Great Exhibition Road Festival - Uncovering our future in Antarctica's past |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Public/other audiences |
Results and Impact | Sparked questions and discussion afterwards. |
Year(s) Of Engagement Activity | 2019 |
URL | https://www.greatexhibitionroadfestival.co.uk/event/uncovering-our-future-antarcticas-past/?backto=w... |
Description | History of Antarctic drilling video |
Form Of Engagement Activity | A broadcast e.g. TV/radio/film/podcast (other than news/press) |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | Participated in filming for a video on the history of Antarctic drilling. |
Year(s) Of Engagement Activity | 2018 |
URL | https://www.youtube.com/watch?v=GN9faSiGUZQ |
Description | Inaugural lecture |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Regional |
Primary Audience | Other audiences |
Results and Impact | Inaugural lecture to a broad audience of colleagues, friends, and the general public. |
Year(s) Of Engagement Activity | 2019 |
URL | https://www.imperial.ac.uk/events/96929/drilling-for-our-future-in-antarcticas-past/ |
Description | London International Youth Science Forum |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | Yes |
Geographic Reach | International |
Primary Audience | Schools |
Results and Impact | Outreach talk on Antarctic Science at the London International Youth Science Forum Enthusiastic response from participating pupils. |
Year(s) Of Engagement Activity | 2010 |
Description | MAGIC Elements |
Form Of Engagement Activity | Participation in an open day or visit at my research institution |
Part Of Official Scheme? | No |
Geographic Reach | Regional |
Primary Audience | Public/other audiences |
Results and Impact | Hundreds of under-12s visited the Imperial Festival stand on MAGIC Elements with their parents. They dressed up as scientists, learned about elements and isotopes, and even about how Antarctica once was a continent with palm trees at its shorelines. |
Year(s) Of Engagement Activity | 2018 |
URL | https://www.imperial.ac.uk/news/185986/imperial-festival-transforms-under-12s-into-mini/ |
Description | Media contact Grantham |
Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | Part of a small group of Grantham affiliates that helps with media requests. My expertise is in the are of palaeoclimate and Antarctic ice sheets |
Year(s) Of Engagement Activity | 2016,2017,2018,2019 |
Description | Open Day 2014 |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Regional |
Primary Audience | Schools |
Results and Impact | Talk about Earth Science at College wide Open Day. Hopefully it inspires pupils to come and study Earth Sciences! |
Year(s) Of Engagement Activity | 2014 |
Description | Pint of Science 2014 |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | Yes |
Geographic Reach | Regional |
Primary Audience | Public/other audiences |
Results and Impact | Outreach talk in a pub to explain science to the general public in a friendly environment. Sparked great discussions on Antarctic ice sheets and sea level change under future climate conditions. |
Year(s) Of Engagement Activity | 2014 |
Description | Pint of Science 2018 |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Regional |
Primary Audience | Public/other audiences |
Results and Impact | Outreach talk in a pub to explain science to the general public in a friendly environment. |
Year(s) Of Engagement Activity | 2018 |
URL | https://pintofscience.co.uk/event/understanding-antarctica |
Description | Podcast interview |
Form Of Engagement Activity | Engagement focused website, blog or social media channel |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | 1 hour interview for the forecast, a podcast about climate science and climate scientists. Long format interviews with Nature's editor for climate science, Michael White. |
Year(s) Of Engagement Activity | 2016 |
URL | http://forecastpod.org/?s=tina+van+de+Flierdt |
Description | Royal Meterological Society meeting - the Pliocene |
Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Media (as a channel to the public) |
Results and Impact | Media briefing ahead of the Pliocene meeting organised by the Royal Meterological Society and the Grantham Institute for Climate and the Environment and hosted by the Science Media Centre. |
Year(s) Of Engagement Activity | 2019 |
Description | Royal Meterological Society meeting - the Pliocene |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | Stimulating meeting to highlight the relevance of the Pliocene climate to our own future. Well attended. Sparked questions and discussion. |
Year(s) Of Engagement Activity | 2019 |
URL | https://www.rmets.org/event/pliocene-last-time-earth-had-400-ppm-atmospheric-co2 |
Description | Shipboard outreach program |
Form Of Engagement Activity | A magazine, newsletter or online publication |
Part Of Official Scheme? | Yes |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | A number of weekly videos as well as a trailer and an expedition summary were produced by a professional videographer on the JOIDES Resolution and were distributed via YouTube. Gained lots of enthusiastic responses and marked a novel way to do outreach on an IODP expedition. |
Year(s) Of Engagement Activity | 2010 |
Description | Talk for year 4 in Judith Kerr primary school |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Schools |
Results and Impact | I talked to school pupils who had discussed Antarctic discovery as part of their curriculum about my experiences on research expeditions to Antarctica. I probably have never answer more questions in one hour than from these enthusiastic 7-year olds. |
Year(s) Of Engagement Activity | 2019 |
Description | |
Form Of Engagement Activity | Engagement focused website, blog or social media channel |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | Tweets about climate change, Antarctica, women in science, STEM related topics and (Earth) Science in general. |
Year(s) Of Engagement Activity | 2014,2015,2016,2017,2018,2019,2020 |
Description | UK Antarctic Research talk 2014 |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Other academic audiences (collaborators, peers etc.) |
Results and Impact | Overview talk on the provenance work on Antarctic ice sheets. Was received well by the Antarctic research community. |
Year(s) Of Engagement Activity | 2014 |
Description | UK IODP conference 2014 |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Other academic audiences (collaborators, peers etc.) |
Results and Impact | Keynote speaker at the UK IODP conference. Reported results of IODP Expedition 318 to date. Great feedback on how successful this particular expedition was, and great discussions about the work done in my group. |
Year(s) Of Engagement Activity | 2014 |
Description | Year 9 girls summer school |
Form Of Engagement Activity | Engagement focused website, blog or social media channel |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Schools |
Results and Impact | Webinar to enthuse year 9 girls for engineering - sparked questions and discussions |
Year(s) Of Engagement Activity | 2021 |
Description | evening lecture |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Public/other audiences |
Results and Impact | Evening talk at the Harrow and Hillingdon Geological Society in NE London on 'Reconstructing the history of the Antarctic ice sheet. Clues from the past for the future?' Talk lead to a very good discussion with the members of the society and a follow up write-up in their monthly newsletter. |
Year(s) Of Engagement Activity | 2011 |