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This venture is the product of a series of Bolin Centre Research area 6 (Deep time climate variability) and Research area 1 (Ocean-atmosphere dynamics and climate) projects focusing on the Miocene as a past warm climate analogue.

The Bolin Centre Data Base and database experts Rezwan Mohammad and Anders Moberg built the portal, which is now 'live'.

sea surface temperatures map
Middle Miocene (~20⁠–⁠14 million years ago) sea surface temperatures (horizontal scale) and model topography (meters above sea level, vertical scale) are shown here. Sea surface temperatures are derived from the multimodel mean of all simulations forced with middle Miocene boundary conditions, as given by Burls et al. [2021, Table 2]. Topography is from the updated Herold boundary conditions as given by Burls et al. [2021]. Credit: Natalie Burls
microscopic image, Eighteen-million-year-old planktonic foraminifera fossils from the Atlantic Ocean
Eighteen-million-year-old planktonic foraminifera fossils from the Atlantic Ocean, seen here under a light microscope, are one type of geological material used for producing Miocene sea surface temperature estimates. Using these types of calcium carbonate shells, scientists can measure three different geochemical temperature proxies: clumped isotopes (Δ47), traditional oxygen stable isotopes (δ18O), and magnesium/calcium ratios (Mg/Ca). Records using all of these approaches appear in the Miocene temperature portal. Other temperature proxy types (TEX86 and UK’37) are measured on fossilized organic molecules. Credit: Helen Coxall