Wed 24 Apr 17:30: Natural and forced behaviour of the Pacific Walker Circulation over the past 800 years Building doors are card operated, so latecomers may not be able to access the venue.
The Pacific Walker Circulation (PWC) is an important part of the global climate system, and affects weather and climate all over the world. However, our observational records of the climate system are too short to characterise the PWC ’s long-term internal variability, as well as how the PWC responds to external forcings such as volcanic eruptions and anthropogenic forcings.
In this seminar I will share a reconstruction of the PWC ’s behaviour over the past 800 years. I will outline how I calculated this reconstruction using a network of globally-distributed water isotope proxy records, as well as how I quantified uncertainties from different sources. I will share some new insights this reconstruction has allowed, including a close examination of the PWC ’s response to both volcanic and anthropogenic forcing.
Building doors are card operated, so latecomers may not be able to access the venue.
- Speaker: Georgina Falster, Australian National University
- Wednesday 24 April 2024, 17:30-19:00
- Venue: Small Lecture Theatre, Department of Geography, Downing Site.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Wed 05 Jun 17:30: Extreme glacial implies discontinuity of early human occupation of Europe Building doors are card operated, so latecomers may not be able to access the venue.
The oldest known hominin remains in Europe [ca. 1.5 to 1.1 million years ago (Ma)] have been recovered from Iberia, where paleoenvironmental reconstructions have indicated warm and wet interglacials and mild glacials, supporting the view that once established, hominin populations persisted continuously. We report analyses of marine and terrestrial proxies from a deep-sea core on the Portugese margin that show the presence of pronounced millennial-scale climate variability during a glacial period ca. 1.154 to 1.123 Ma, culminating in a terminal stadial cooling comparable to the most extreme events of the last 400,000 years. Climate envelope–model simulations reveal a drastic decrease in early hominin habitat suitability around the Mediterranean during the terminal stadial. We suggest that these extreme conditions led to the depopulation of Europe, perhaps lasting for several successive glacial-interglacial cycles.
Building doors are card operated, so latecomers may not be able to access the venue.
- Speaker: Vasiliki Margari, University College London
- Wednesday 05 June 2024, 17:30-19:00
- Venue: Harker 1, Department of Earth Sciences, Downing Street.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Wed 05 Jun 17:30: Extreme glacial implies discontinuity of early human occupation of Europe Building doors are card operated, so latecomers may not be able to access the venue.
The oldest known hominin remains in Europe [1.5 to 1.1 million years ago (Ma)] have been recovered from Iberia, where paleoenvironmental reconstructions have indicated warm and wet interglacials and mild glacials, supporting the view that once established, hominin populations persisted continuously. We report analyses of marine and terrestrial proxies from a deep-sea core on the Portugese margin that show the presence of pronounced millennial-scale climate variability during a glacial period 1.154 to 1.123 Ma, culminating in a terminal stadial cooling comparable to the most extreme events of the last 400,000 years. Climate envelope–model simulations reveal a drastic decrease in early hominin habitat suitability around the Mediterranean during the terminal stadial. We suggest that these extreme conditions led to the depopulation of Europe, perhaps lasting for several successive glacial-interglacial cycles.
Building doors are card operated, so latecomers may not be able to access the venue.
- Speaker: Vasiliki Margari, University College London
- Wednesday 05 June 2024, 17:30-19:00
- Venue: Harker 1, Department of Earth Sciences, Downing Street.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Wed 24 Apr 17:30: Natural and forced behaviour of the Pacific Walker Circulation over the past 800 years Building doors are card operated, so latecomers may not be able to access the venue.
Abstract not available
Building doors are card operated, so latecomers may not be able to access the venue.
- Speaker: Georgina Falster, Australian National University
- Wednesday 24 April 2024, 17:30-19:00
- Venue: Small Lecture Theatre, Department of Geography, Downing Site.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Wed 24 Apr 17:30: Natural and forced behaviour of the Pacific Walker Circulation over the past 800 years Building doors are card operated, so latecomers may not be able to access the venue.
Abstract not available
Building doors are card operated, so latecomers may not be able to access the venue.
- Speaker: Georgnia Falster, Australian National University
- Wednesday 24 April 2024, 17:30-19:00
- Venue: Small Lecture Theatre, Department of Geography, Downing Site.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Wed 05 Jun 17:30: TBC Building doors are card operated, so latecomers may not be able to access the venue.
Abstract not available
Building doors are card operated, so latecomers may not be able to access the venue.
- Speaker: Vasiliki Margari, University College London
- Wednesday 05 June 2024, 17:30-19:00
- Venue: Harker 1, Department of Earth Sciences, Downing Street.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Wed 12 Jun 17:30: Palaeoecological Insights into the Causes and Consequences of Mid-Late Quaternary Megafauna Extinction in Asia and Australia Building doors are card operated, so latecomers may not be able to access the venue.
Mid-Late Quaternary megafauna extinctions have long intrigued researchers seeking to understand the causes and consequences of these significant ecological events. What role did fluctuations in climate, shifts in vegetation composition, alterations in habitat distribution, and the impact of human settlement play in megafauna extinction? One way to help us better understand the role of environmental change in the extinction process is to use palaeoecological techniques (pollen, spore and charcoal analysis) combined with well resolved geochronological estimates to reconstruct palaeoenvironmental conditions that occur before, during, and after past megafauna extinctions. Here I present two palaeoecological case studies that provide insights into megafauna extinction in Asia and Australia: (i) the largest ever primate and one of the largest of the southeast Asian megafauna, Gigantopithecus blacki, that persisted in China from about 2.0 million years until the late middle Pleistocene when it became extinct, well before the appearance of Homo sapiens on the landscape, and (ii) the multiple extinctions of megafauna that occurred across Australia around 50,000-40,000 years ago that coincide with a time when people were present across the Australian landscape. This presentation underscores the importance of interdisciplinary approaches integrating palaeoecological, geochronological, archaeological, and climatological perspectives to unravel the complexities of past megafauna extinctions and inform strategies for mitigating future biodiversity crises.
Building doors are card operated, so latecomers may not be able to access the venue.
- Speaker: Simon Haberle, Australian National University
- Wednesday 12 June 2024, 17:30-19:00
- Venue: Small Lecture Theatre, Department of Geography, Downing Site.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Wed 15 May 17:30: Radiocarbon dating and conspiracy theories Building doors are card operated, so latecomers may not be able to access the venue.
A range of conspiracy theories involving radiocarbon dating have become popular on the Internet over the past years. Examples include the radiocarbon dating of dinosaur fossils that supposedly reveal problems with a geologically old Earth, claims that entire centuries of European history have been made up, and archaeological sites that supposedly provide evidence for a long-lost Younger Dryas civilization that is being hidden or denied by “Big Archaeology”. We will look at what these conspiracy theories claim, followed by more down-to-Earth explanations. We then discuss the dangers of such conspiracy theories, and provide some pointers for dealing with them.
Building doors are card operated, so latecomers may not be able to access the venue.
- Speaker: Maarten Blaauw, Queen's University Belfast
- Wednesday 15 May 2024, 17:30-19:00
- Venue: Large Lecture Theatre, Department of Geography, Downing Site.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Wed 24 Apr 17:30: Title to be confirmed Building doors are card operated, so latecomers may not be able to access the venue.
Abstract not available
Building doors are card operated, so latecomers may not be able to access the venue.
- Speaker: Georgnia Falster, Australian National University
- Wednesday 24 April 2024, 17:30-19:00
- Venue: Small Lecture Theatre, Department of Geography, Downing Site.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Wed 15 May 17:30: Radiocarbon dating and conspiracy theories
A range of conspiracy theories involving radiocarbon dating have become popular on the Internet over the past years. Examples include the radiocarbon dating of dinosaur fossils that supposedly reveal problems with a geologically old Earth, claims that entire centuries of European history have been made up, and archaeological sites that supposedly provide evidence for a long-lost Younger Dryas civilization that is being hidden or denied by “Big Archaeology”. We will look at what these conspiracy theories claim, followed by more down-to-Earth explanations. We then discuss the dangers of such conspiracy theories, and provide some pointers for dealing with them.
- Speaker: Maarten Blaauw, Queen's University Belfast
- Wednesday 15 May 2024, 17:30-19:00
- Venue: Venue to be confirmed.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Wed 05 Jun 17:30: TBC
Abstract not available
- Speaker: Vasiliki Margari, University College London
- Wednesday 05 June 2024, 17:30-19:00
- Venue: Harker 1, Department of Earth Sciences, Downing Street.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Wed 06 Mar 17:30: 50,000 years of turnover and extinction in high-latitude megafauna communities Building doors are card operated, so latecomers may not be able to access the venue.
Abstract not available
Building doors are card operated, so latecomers may not be able to access the venue.
- Speaker: Alistair Monteath, British Antarctic Survey
- Wednesday 06 March 2024, 17:30-19:00
- Venue: Small Lecture Theatre, Department of Geography, Downing Site.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Wed 24 Apr 17:30: Title to be confirmed
Abstract not available
- Speaker: Georgnia Falster, Australian National University
- Wednesday 24 April 2024, 17:30-19:00
- Venue: Venue to be confirmed.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Wed 15 May 17:30: Title to be confirmed
Abstract not available
- Speaker: Maarten Blaauw, Queen's University Belfast
- Wednesday 15 May 2024, 17:30-19:00
- Venue: Venue to be confirmed.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Wed 12 Jun 17:30: Palaeoecological Insights into the Causes and Consequences of Mid-Late Quaternary Megafauna Extinction in Asia and Australia Building doors are card operated, so latecomers may not be able to access the venue.
Mid-Late Quaternary megafauna extinctions have long intrigued researchers seeking to understand the causes and consequences of these significant ecological events. What role did fluctuations in climate, shifts in vegetation composition, alterations in habitat distribution, and the impact of human settlement play in megafauna extinction? One way to help us better understand the role of environmental change in the extinction process is to use palaeoecological techniques (pollen, spore and charcoal analysis) combined with well resolved geochronological estimates to reconstruct palaeoenvironmental conditions that occur before, during, and after past megafauna extinctions. Here I present two palaeoecological case studies that provide insights into megafauna extinction in Asia and Australia: (i) the largest ever primate and one of the largest of the southeast Asian megafauna, Gigantopithecus blacki, that persisted in China from about 2.0 million years until the late middle Pleistocene when it became extinct, well before the appearance of Homo sapiens on the landscape, and (ii) the multiple extinctions of megafauna that occurred across Australia around 50,000-40,000 years ago that coincide with a time when people were present across the Australian landscape. This presentation underscores the importance of interdisciplinary approaches integrating palaeoecological, geochronological, archaeological, and climatological perspectives to unravel the complexities of past megafauna extinctions and inform strategies for mitigating future biodiversity crises.
Building doors are card operated, so latecomers may not be able to access the venue.
- Speaker: Simon Haberle, Australian National University
- Wednesday 12 June 2024, 17:30-19:00
- Venue: Venue to be confirmed.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Wed 06 Mar 17:30: 50,000 years of turnover and extinction in high-latitude megafauna communities Building doors are card operated, so latecomers may not be able to access the venue.
Abstract not available
Building doors are card operated, so latecomers may not be able to access the venue.
- Speaker: Alistair Monteath, British Antarctic Survey
- Wednesday 06 March 2024, 17:30-19:00
- Venue: Small Lecture Theatre, Department of Geography, Downing Site.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Wed 21 Feb 17:30: Microplastics from geologists' perspective Building doors are card operated, so latecomers may not be able to access the venue.
Abstract not available
Building doors are card operated, so latecomers may not be able to access the venue.
- Speaker: Saija Saarni, University of Turku
- Wednesday 21 February 2024, 17:30-19:00
- Venue: Small Lecture Theatre, Department of Geography, Downing Site.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Wed 07 Feb 17:30: The West Antarctic Ice Sheet and sea level in the last interglacial Building doors are card operated, so latecomers may not be able to access the venue.
There is intense interest in the future stability of the West Antarctic Ice Sheet (WAIS). Models range widely in their predictions and in the physics they include. We can constrain possible outcomes by observing what happened to ice sheets at previous times when the polar regions were warmer than present. The last interglacial (LIG) is a particularly important time because both Greenland and Antarctic temperature were higher than present and so was sea level.
Within the WACSWAIN (WArm Climate Stability of the West Antarctic ice sheet in the last INterglacial) project, in 2019 we retrieved a 651 metre ice core to the bed of Skytrain Ice Rise. This ice rise is adjacent to the Ronne Ice Shelf and the WAIS , and therefore sensitive to their extent. The ice core has been processed and analysed continuously for a range of analytes, and we can show that ice from the LIG is present.
I will start by describing the project, fieldwork and analyses. Eventually, I will show what happened to the ice around Skytrain Ice Rise in the LIG , and discuss how this fits with other evidence about LIG sea level.
Building doors are card operated, so latecomers may not be able to access the venue.
- Speaker: Eric Wolff, Department of Earth Sciences, and the WACSWAIN team
- Wednesday 07 February 2024, 17:30-19:00
- Venue: Harker 2, Department of Earth Sciences, Downing Street.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Wed 15 May 17:30: Title to be confirmed
Abstract not available
- Speaker: Maarten Blaauw, Queen's University Belfast
- Wednesday 15 May 2024, 17:30-19:00
- Venue: Venue to be confirmed.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
Wed 24 Apr 17:30: Title to be confirmed
Abstract not available
- Speaker: Georgnia Falster, Australian National University
- Wednesday 24 April 2024, 17:30-19:00
- Venue: Venue to be confirmed.
- Series: Quaternary Discussion Group (QDG); organiser: Jinheum Park.
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