PMIP Ocean Workshop 2013 - Understanding Changes Since the Last Glacial Maximum

04.12 - 06.12.2013
Corvallis, USA
Contact person:
Andreas Schmittner, This email address is being protected from spambots. You need JavaScript enabled to view it.
Workshop report: 
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The Paleoclimate Model Intercomparison Project in its third phase (PMIP3) includes simulations with comprehensive climate models of the Last Glacial Maximum (LGM), the Mid-Holocene, and the last Millennium. PMIP3 results, some of which are part of the Coupled Model Intercomparison Project 5 (CMIP5), are becoming available for analysis now.

An important task will be to evaluate the ocean simulations including circulation patterns and strengths. Here we want to facilitate this evaluation by updating existing datasets of surface and deep temperatures, carbon isotopes (δ13C and Δ14C), as well as other relevant proxies (e.g. Pa/Th, Nd) including revisions of the chronologies and proxy uncertainties. Another goal of the workshop will be to bring together sea-going paleoceanographers, modelers, and statisticians in an effort to collaboratively improve our understanding of ocean changes since the LGM.

Scientific questions addressed will include

- What were the temperatures, salinities, and ice cover of the ocean since the LGM
- What was the global deep ocean circulation and carbon cycle during the LGM and its variability during the Late Holocene (LH)?

Methodological issues

- What are issues in interpreting proxies (e.g. δ13C, Δ14C , SST forams vs Mg/Ca, chronologies)
- How can we use models and data together to address the scientific questions posed above?

Organizational issues

- Do we need a PAGES Working Group
- Do we want to create a new INQUA International Focus Group?

The workshop will contribute to a better understanding of the glacial carbon cycle and its glacial-interglacial variations. Most current hypotheses explain lower glacial CO2 concentrations in the atmosphere by more carbon storage in the glacial ocean. However, the locations and reasons for changes in ocean carbon storage remain mysterious. Carbon isotopes include important information on past changes in ocean carbon cycle and circulation. However, their interpretation is complicated by issues such as fractionation during air-sea gas exchange (for δ13C) and reservoir ages and other dating issues (for radiocarbon). Other proxies such as Pa/Th and Nd isotopes include additional, sometimes complimentary information but have their own uncertainties. Because of these issues a promising strategy for a better understanding is a combination of observations with process-based models aided by state-of-the science statistical methods. We expect that this effort will uncover many unpublished data, result in improved chronologies, better quantification of uncertainties and application of advanced statistical methods of model-data fusion.


Deadline for registration, abstract submission, and application for travel support: Aug. 31, 2013.

Meeting material

> Website 

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> Abstracts



This workshop is funded by the Marine Geology and Geophysics Program of the National Science Foundation (NSF) and the Past Global Changes (PAGES) project of the International Geosphere-Biosphere Program (IGBP). Limited funding for travel expenses is available. Early career researchers and scientists from developing countries are particularly encouraged to apply.

Organizing committee

A. Schmittner, A. Mix, S. Khatiwala, A. Abe-Ouchi, S. Mulitza, N. Urban