New study shows how past Arctic sea ice loss was linked to abrupt climate warming

A new study on Greenland ice cores shows that Arctic sea ice loss in the period 30-100,000 years ago was associated with major oscillations in high latitude climate. During this period, Greenland temperatures repeatedly increased by up to 16°C in less than a century, followed by more gradual cooling. The results are published today (Monday 11 February) in the journal Proceedings of the National Academy of Sciences (PNAS).

The team, led by Dr Louise Sime from the British Antarctic Survey, includes Dr Rachael Rhodes an ice core scientist who recently joined CAPE at Northumbria. Dr Rhodes explains what the study involved:

“We studied data from ice cores drilled in Greenland, focusing on records of oxygen isotopes that are the poster-child example of abrupt climate change. We compared these records to output from sophisticated climate models able to simulate how the oxygen isotopic mix of the ice changes with climate and sea ice conditions.”

From this Dr Rhodes and the team determined that rapid, extensive sea retreat was a hugely important control on the oxygen isotope signals. This is a significant result because the abrupt climate warmings, called Dansgaard-Oeschger events after the two scientists who first discovered them, are some of the fastest and largest abrupt climate changes ever recorded. Now that we better understand how sea ice loss is imprinted on Greenland ice cores, we move closer to deciphering between competing theories about what actually triggered these remarkable climate events.

Even though Dansgaard-Oeschger events occurred in an ice age when the Arctic was much colder than it is today, Dr Rhodes says it is critical to learn about the climate impacts of past Arctic sea ice loss given that Arctic sea ice extent is currently decreasing in our warming world.

Impact of abrupt sea ice loss on Greenland water isotopes during the last glacial period by Louise C. Sime, Peter O. Hopcroft, Rachael H. Rhodes is published in the Proceedings of the National Academy of Sciences here.

Research Fellow in Ice Core Geochemistry

Applications are invited for a Postdoctoral Research Fellow in ice core geochemistry and past greenhouse gas variability. The successful candidate is to be employed by Northumbria University to work as a researcher on the Royal Society funded project ‘Augmenting ice core records with continuous histories of CO2, CH4 and N2O” (RGF\EA\181047). The Postdoctoral Researcher will develop methods to measure the concentration and isotopic composition of atmospheric gases trapped in polar ice cores. The successful candidate will work closely with researchers at the British Antarctic Survey, University of Bern and Oregon State University to generate new data on existing Antarctic ice cores and will be expected to disseminate the results in peer-reviewed journals and at conferences.

The ideal candidate will have expert knowledge in geochemistry with an emphasis on stable isotope mass spectrometry. Experience in Quaternary Science, greenhouse gas biogeochemistry, ice core gas geochemistry and other palaeoclimate methods is desirable.

Candidates will be expected to disseminate research findings in peer-reviewed publications and/or international conferences.  Applicants must hold a PhD degree (or close to completion) in Earth Science, Geology, Physical Geography, Atmospheric Chemistry or related discipline. For further details and to apply, please click here.

Vice-Chancellor’s Fellow in Geography and Environmental Sciences

We are currently seeking to appoint a Vice-Chancellor’s Fellow to further develop our research profile and activity.

We are particularly interested in high-quality applications from candidates who will either align with our areas of existing strength, or support us in growing capacity in allied areas. Current research themes in the Department include extreme environments, cryospheric science, palaeoenvironmental reconstruction, bioavailability of environmental pollutants, ecological resilience, carbon cycling, sustainable development, risk reduction, creative industries, identities and inequality, media convergence, everyday b/ordering and visual methodologies.

You will have the opportunity to demonstrate your extensive knowledge and subject expertise through individual and collaborative academic activity. Successful candidates will be selected according to the excellence of their research profile and plans (candidates are encouraged to include a two-page research plan in their application), regardless of their area of research interest.

Posts are for three years with the expectation of moving to a permanent academic contract (subject to the usual criteria). For more information about the Department and its research please visit our homepage.

For informal enquiries about these Fellowships please contact the Head of Department, Professor Ben Brock,, or the Subject Lead for Physical Geography and Environmental Sciences: Professor Hilmar Gudmundsson:

To apply for this vacancy please click here.

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