Climate evolution of the Earth-like planets with surface plate motion in a whole Earth system evolution model

Abstract

For revealing a habitability of terrestrial planets such as the Earth, it is essential to investigate the system which includes plate motion driven by mantle convection and warm climate with oceans composed of liquid water plus continuous generation of geomagnetic field. In particular, the surface plate motion is significant for the volcanic degassing of CO2and H2O that affects evolution of the atmosphere, ocean, and climate, which means that the mantle dynamics plays an important role in climate evolution. Here we focus on how the surface plate motion (mobile lid or stagnant lid) affects the climate evolution over the geologic time-scale in a coupled evolution model of mantle convection including volatile migration and core evolution and energy balance model for climate evolution (i.e. a whole Earth system evolution model). With this model, we can evaluate the long-term evolution of whole planetary system as well as its habitability. Based on the results of numerical simulations, the surface climate may be strongly affected by the style of surface plate motion, that is, warm climate would be expected for the mobile lid planet over the geologic time-scale because the degassing flux is sufficient to sustain the warm climate. Whereas, cold climate would be found for the stagnant lid planet caused by the small degassing flux. Moreover, for sustaining the geomagnetic field, the mobile lid planet may have geodynamo actions for the geologic time-scale, however, the stagnant lid planet is difficult to maintain the geomagnetic field generation. It is therefore difficult to find the habitable condition (warm climate that may have the liquid water and geomagnetic field) for a stagnant lid planet.