Pliocene and Miocene climate variability over glacial-interglacial timescales
Photo: Ras il-Pellegrin outcrop Malta [Mid-Miocene (13.82 Ma)] from Ray Zammit
The Pliocene (~2.6-5.3 myr) and the Miocene (~5.3-23 myr), are globally warm climate states with atmospheric CO2 concentrations estimated to be similar and/or higher than today. The Pliocene and Miocene are characterized by higher global mean surface temperatures (~2-3 ºC), reduced ice volume, and reduced ocean and atmospheric strength in comparison to pre-industrial.
The mid-Pliocene warm period (MPWP) has long been a data-model comparison target for the paleoclimatology community (USGS PRISM datasets, PlioMIP, PlioVAR). And though CO2 during the MPWP is estimated to be similar to today, there is increasing need to expand into the early Pliocene and Miocene for higher CO2 and globally warm equilibrium climate states for data-model comparisons to understand future climate change (i.e. mid-Miocene Climate Optimum). The Pliocene and Miocene were discussed in the recent Intergovernmental Panel on Climate Change, 6th Assessment Report, Working Group 1 as informing our understanding of warm climate states and therefore continue to be important data-model comparison targets in constraining future climate change.
To address this need, PlioMioVAR aims to expand the stratigraphical framework of PlioVAR to include low and high-resolution stratigraphy datasets for a variety of proxies: sea surface temperature, productivity, benthic stable isotopes, etc for the early Pliocene through Miocene.
This group is open to anyone who is interested, and early-career researchers are encouraged to be involved:
The overall goal of PlioMioVAR is to co-ordinate a synthesis of terrestrial and marine data to characterise spatial and temporal variability of Pliocene and Miocene climate. Our programme builds on key priorities identified by the community in the PAGES PlioVAR working group (2015-2018) and includes the nascent Miocene community (Paleoceanography and Paleoclimatology 2019 Special Issue - The Miocene: The Future of the Past). This is an opportunity to share best practices in community-wide engagement, database building and data-model comparison. The PlioMioVAR effort will be punctuated by a series of workshops as described below.
First planned workshop: ”The warm Pliocene: Bridging the geological data and modelling communities” is scheduled for August 2022. This workshop will report the major achievements of PlioVAR and PlioMIP2. During this time new Pliocene synthesis goals will be developed and delegated for updating the PlioVAR database. Future plans for opportunities for data-model integration and transient and biogeochemical modelling will be discussed. Product: plan for PlioVAR database expansion and maintenance.
The second planned workshop will focus on the Miocene database and take place in Winter 2022. During this time Miocene database synthesis goals will be developed and delegated. Much of the scaffolding for database production (quality control, stratigraphical frameworks, database template) will be adopted from PlioVAR. The initial Miocene database will be expanded to multiple proxies. Synthesis goals will be developed and delegated to expand the database. Product: plan for MioVAR database expansion and maintenance.
The third planned workshop will focus on climate modelling for the Miocene. Assess the role of equilibrium and transient experiments; explore introduction of new earth system components such as biogeochemistry; assess PlioMIP intercomparison approaches and findings and share best practices with MioMIP. Product: creation and implementation of model experiments for MioMIP.
The fourth planned workshop will bring the data and modelling communities together to synthesize Pliocene and Miocene Climate. This will serve as an opportunity for future manuscript outlining and production. Products: active data-base detailing multi-proxy records of Pliocene and Miocene climate; publications detailing syntheses and data-model comparisons for the mid-Pliocene and and Mid-Miocene Climate Optimum (PMIP targets for IPCC).
The Steering Committee will co-ordinate and support the development of the database, maintain communication with all members of the Working Group, and monitor progress against each of our objectives and liaise and co-ordinate with the ongoing PlioMIP and MioMIP Projects.
Heather Ford (Queen Mary University of London, UK) Sindia Sosdian (Cardiff University, UK) Erin McClymont (Durham University, UK)
ECR Sevi Modestou (Northumbria University, UK) Natalie Burls (George Mason University, USA - MioMIP Steering Committee Representative/Leader) Aisling Dolan (Leeds University, UK - PlioMIP Steering Committee Representative) Ling Ho (National Taiwan University, Taiwan)