Miocene · 5–23 million years ago
A global database of Miocene ocean temperatures.
A resource for anyone reconstructing Miocene climate — organic and inorganic temperature proxies from marine sediment cores and outcrop sections, harmonised on shared age models.
One synthesis for a fragmented record.
MioOcean is compiled and maintained by the MioOcean Temperature Synthesis Working Group, a subgroup of PAGES PlioMioVAR. Its goal: update age models of existing ocean temperature records, integrate heterogeneous datasets, and ultimately build a global temperature atlas for the Miocene.
◆ PAGES PlioMioVAR subgroup
Five ways to read a warmer ocean.
We reconstruct past ocean temperatures using organic and inorganic proxies obtained from marine sediment cores and terrestrial outcrop sections.
Where the record comes from.
Sites span every major ocean basin — deep-sea drilling cores and uplifted outcrop sections, each tied to a revised age model so records can be compared like-for-like.
Meet the team.
A large international group of 55 people across 7 working groups, led by the MioOcean steering committee.
Questions, answered.
What is MioOcean?
MioOcean is a global database of Miocene ocean temperature proxy data — a shared resource for reconstructing ocean climate between roughly 5 and 23 million years ago.
What are paleo-oceanographic proxies?
Proxies are measurable properties preserved in marine sediments — the chemistry of fossil shells or organic molecules — that stand in for ocean conditions such as temperature when direct measurements are impossible.
What are foraminifera and why do they matter for the ocean?
Foraminifera are single-celled marine organisms whose calcite shells accumulate on the seafloor. Their chemistry records the temperature and composition of the water they grew in, making them a cornerstone archive of past oceans.
How are MioOcean data collected?
Records come from marine sediment cores and terrestrial outcrop sections, measured with organic and inorganic proxy methods and placed on revised, harmonised age models before entering the compilation.
Why are multiple proxies needed to reconstruct past ocean conditions?
Each proxy carries its own assumptions and sensitivities. Combining independent organic and inorganic methods cross-checks results and produces more robust temperature reconstructions.
How can educators or students use MioOcean?
The compilation and data explorer are openly accessible, making them well suited for teaching about deep-time climate, proxy methods, and how scientists reconstruct past oceans.
Can I download or reuse MioOcean datasets?
Yes — compiled datasets are available to download and reuse, with citation. New records can also be contributed back through the submission template.
Contribute
Send us your new Miocene temperature data.
Have a published or in-prep record? Add it to the compilation using our submission template and help complete the atlas.