Ocean lithium concentrations declined sevenfold over 150 million years

Analysis of salt samples has revealed that lithium concentrations in seawater have declined sevenfold over the last 150 million years. Previously, researchers had assumed the lithium concentration was constant, but the new findings help to explain larger geological effects, including relationships with climate and the carbon cycle.

‘Turning back the clock by 150 million years, the Earth was warmer, with more carbon dioxide in the atmosphere and more lithium in the sea,’ explains geoscientist Mebrahtu Weldeghebriel from Princeton University in the US, who led the new research. ‘The ocean is like a giant soup of elements, [and] it’s important to understand how they respond to major changes to [deduce] the link between ocean chemistry and atmospheric chemistry.’