Ocean Circulation and Carbon Cycling during the Last Deglaciation: Regional Syntheses of Carbon Isotope Data
- 27.06 - 29.06.2017
- Corvallis, USA
- Contact person:
PAGES' Ocean Circulation and Carbon Cycling (OC3) working group will hold the "Ocean Circulation and Carbon Cycling during the Last Deglaciation: Regional Syntheses of Carbon Isotope Data" workshop in Corvallis, Oregon, USA, from 27-29 June 2017.
The meeting venue is LaSells Steward Center, Oregon State University, Corvallis, Oregon, USA.
The workshop will be open to approximately 40 participants and will include plenary talks and breakout groups.
Earth’s climatic transition from the Last Glacial Maximum (LGM) to the Holocene is still not fully understood. The associated rise in atmospheric CO2 remains unexplained although it is important for the global warming. Ocean circulation changes during the deglaciation have been linked to the rates of CO2 increase. However, the exact mechanism of that link is unclear and quantifying changes in the ocean’s circulation and carbon storage remain challenging tasks.
This workshop will contribute to making progress through new regional syntheses of carbon isotope data throughout the last deglaciation and comparisons of these syntheses to other paleoclimate proxy reconstructions and isotope enabled model simulations. We plan to address questions such as the following:
- When, at what depths, and by how much did carbon isotopes start to change after the LGM in the Atlantic, Pacific, Indian, and Southern Oceans?
- What do these changes imply about ocean circulation?
- How much did the Atlantic Meridional Overturning Circulation (AMOC) decrease during Heinrich Stadial 1 (HS1)? Was it only weakened or completely shut-down?
- Are carbon isotopes consistent with the idea that an AMOC shutdown weakened the biological pump and triggered the initial CO2 rise during HS1?
- Why did CO2 concentrations during the subsequent Bolling-Allerod stay constant?
- What caused the CO2 rise during the final phases of the deglaciation?
- What role did changes in the Southern Ocean and North Pacific play?
Objectives of the workshop are to:
- bring together sea-going paleoceanographers, modelers, and database managers
- discuss database issues such as format, links to other databases, LinkedEarth ontology
- discuss methods and uncertainties of age model construction
- discuss how the database can be used to constrain models of ocean circulation change and our ideas about the release of CO2
- create regional syntheses of benthic carbon isotope measurements
- analyze the syntheses, compare them with each other and with other paleoclimate data and models
- draft manuscripts describing the syntheses and analyses suitable for publication in a special issue of a peer-reviewed journal
- discuss what advances need to be made beyond this compilation.
OC3’s overarching goal is to synthesize foraminiferal carbon isotope (δ13C) data and compare them with model simulations in order to better understand past changes in ocean circulation and carbon cycling. OC3 focusses on the last deglaciation but considers all time periods. δ13C is routinely measured on shells of fossil benthic (deep dwelling) and planktonic (near surface) foraminifera and has been used for a long time as a proxy to infer both carbon cycling as well as deep ocean circulation in the past.
During discussions at the inaugural meeting in Bern and subsequent email conversations and teleconferences, a strategy for the data synthesis has been developed. Part of that strategy is a division into regional syntheses in individual ocean basins and sub-basins. Groups of researchers familiar with specific regions will focus on those regions. Attempts will be made to use common techniques for the development of age models. Different methods will be used and uncertainties will be determined. Preliminary syntheses of global published data and regional data (both published and unpublished) have been assembled.
This will be the second OC3 meeting. It will focus on regional syntheses of benthic carbon isotope data in different basins/sub-basins of the ocean. It will be preceded by an open call for unpublished data and preparatory work to develop the regional syntheses.
Limited funding for travel support is available.
We will work with the Paleoclimate Modeling Intercomparison Project’s (PMIP) working group "Last Deglaciation". The purpose of that working group is to co-ordinate climate model simulations of the last deglaciation including comparison with reconstructions. For the latter purpose our carbon isotope syntheses and data constraints of ocean circulation will be useful. Members of this working group are encouraged to attend the meeting.
LinkedEarth is an NSF funded EarthCube project that aims to facilitate paleoclimate data syntheses. LinkedEarth team members are welcome to attend.
Access the website: http://people.oregonstate.edu/~schmita2/Projects/OC3