Earth’s mantle is thermally and chemically heterogeneous at multiple scales, from the crystal structure of rocks through to slabs and large-scale chemical reservoirs in the deep mantle. An enduring problem in geoscience is that different scales of heterogeneity require different techniques and methods for investigation, yet ultimately we strive for an holistic view on the origin and evolution of mantle heterogeneity from the surface to the core-mantle boundary. Furthermore, mantle and tectonic processes control supercontinent cycles, which drive fundamental evolutionary cycles on Earth, including major sea level fluctuations, extinctions, ocean circulations, and long-term greenhouse-icehouse cycles. For example, coupled plate-mantle processes affecting sea level include dynamic topography, changes in the volume of ocean basins, and changes in the amount of water stored in the Earth's mantle. For this session we invite contributions from all areas of geoscience that involve numerical modelling and/or data analysis to shed light on the plate-mantle system and its role in determining the long-term history of Earth through geological and biological cycles. We aim to facilitate lively and interdisciplinary discussion and provide inspiration for new collaborative studies across different fields.