Make our planet great again: Alessandro Forte joins the IPGP

Run by the French National Research Agency (ANR) and the CNRS, the Make Our Planet Great Again programme is aimed at researchers who do not live in France and who wish to develop, in France and in collaboration with French partners, high-level research projects to tackle climate and global change.

Alessandro Forte is Professor of Geophysics in the Department of Geological Sciences at the University of Florida and Associate Professor in the Department of Earth and Atmospheric Sciences at the Université de Québec à Montréal.

He obtained his PhD in geophysics on mantle convection under the supervision of W. Richard Peltier at the University of Toronto in 1989. He then carried out his postdoctoral research in collaboration with Adam Dziewonski on global seismic tomography in the Department of Earth and Planetary Sciences at Harvard University. It was during this period (from 1989 to 1994) that he developed increasingly realistic physical models linking the Earth’s 3D structure to the dynamics of the mantle and in particular to dynamic processes at the Earth’s surface. It was thanks to this expertise that he obtained his first academic post at the Institut de Physique du Globe de Paris. He was a lecturer at the IPGP from 1994 until the end of 1998, before returning to North America where he continued his research as a professor of geophysics at various universities, including London (Ontario), Montreal (Quebec) and now Florida.

His research has focused mainly on global-scale computer modelling of thermal convection in the Earth’s mantle. One of the main motivations for this research is to determine the impact of deep Earth dynamics on a wide variety of surface geological and geophysical processes. This ‘Earth System’ approach has been used to develop detailed physical models linking fundamental surface processes, such as changes in the Earth’s topography and gravity, and corresponding variations in sea level, to global movements of heat and mass in the deep Earth.

The Gyptis project, on which he will be working as part of the IPGP’s geomagnetism team, will map the spatio-temporal links between the Earth’s internal dynamics and the geological markers that record climate variations. The data of particular interest are sea levels recorded during warm geological periods (notably the Pleistocene, Pliocene and Palaeocene-Eocene interglacials). Sea level records during these warm periods provide important clues about the future vulnerability of polar ice masses.

Internal dynamics are driven by global movements of hot rocks in the mantle, a process known as “thermal convection”. Recently, it has become clear that convection in the mantle can disrupt processes such as crustal topography or the drift of the Earth’s rotation pole, on multi-millennial timescales, where glacial isostatic adjustment is generally considered to be dominant.

This project will therefore carry out cutting-edge geodynamic computer simulations based on realistic models of the 3-D structure and viscosity of the mantle. These calculations will reconstruct the evolution of mantle dynamics over the last 70 million years. This modelling, coupled with data analysis, will seek to resolve outstanding questions about the origins of past changes in sea level and their implications for future changes.

Find out more:

• see the list of the 12 winners of the 3rd wave on the website of the French Ministry of Higher Education, Research and Innovation.