Peter van der Beek is awarded an ERC Advanced Grant

Peter van der Beek

On 28 March, the European Research Council (ERC) published the list of awardees of its Advanced Grants [1] 2019. Among the 222 projects selected (out of 2052 submitted), including 31 based in France and 10 in the Earth and Environmental Sciences, is the project COOLER (Climatic Controls on Erosion Rates and Relief of Mountain Belts) proposed by Peter van der Beek, professor at the ISTerre [2] / OSUG laboratory.

The interactions between tectonics, erosion and climate play a fundamental role in the long-term evolution of the Earth’s climate; understanding these couplings is necessary to differentiate between natural and anthropogenic climate forcing. The COOLER project aims to improve the understanding of the feedbacks between tectonic processes in the lithosphere and climatic processes in the atmosphere.

It has been proposed that global slow and continuous cooling since the beginning of the Cenozoic (the last 65 million years) is linked to the growth of mountain ranges (especially the Himalayas): mountain uplift would increase erosion, and therefore also increase chemical weathering reactions (related to the exhumation of "fresh" rocks) and burial of organic carbon, which would reduce the concentration of CO2 in the atmosphere by its transfer into the lithosphere.

It has also been suggested that the colder and more variable climate of the Pliocene-Quaternary (the last 5 million years) would have led to an increase in erosion and relief growth. If both couplings exist, this would imply that the Earth’s climate is potentially very unstable (as they would form positive feedback loop between climate and erosion), which could explain why the Earth occasionally switches to conditions of global glaciation ("Snowball Earth"). However, the second coupling has not been explicitly demonstrated and remains highly controversial.

The COOLER project proposes to study this coupling in more detail by developing innovative tools to record erosion and relief evolution with unparalleled spatial and temporal resolution. These new data will be integrated into numerical models in order to deduce potential driving mechanisms. This will test the links between Quaternary glaciation and the potential increase in global erosion rates. This project proposes in particular to develop a new very high resolution thermochronology method to record the history of erosion and relief evolution over the last few million years, by setting up the first operational 4He/3He thermochronology laboratory in Europe).