Earth's next supercontinent climate: how tectonics, rotation rate, and insolation affect climate

Tuesday, 8 December 2020
Michael Way, NASA Goddard Institute for Space Studies, New York, NY, United States, Hannah Sophia Davies, Instituto Dom Luis, Lisbon, Portugal, Joao Duarte, Instituto Dom Luiz (IDL), Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal and Mattias Green, Bangor University, School of Ocean Sciences, Bangor, LL59, United Kingdom
We investigate two possible deep future Earth climate scenarios using a 3-D GCM [1] when the next supercontinent phase is expected to take place. In Amasia (forming ~200Myr from now) [2,3] the supercontinent forms at high northerly latitudes with the main continents 'squished' north of the equator while an Antarctic subcontinent remains at the south pole. In Aurica (~250Myr) [3,4] a supercontinent forms at low latitudes akin to that of a Sturtian topography. We utilize the forward evolution of plate tectonics, solar luminosity, and rotation rate in our study. The climates differences between these two scenarios are dramatic, with differences in mean surface temperatures approaching several degrees. These results demonstrate that using a simple aquaplanet or a modern Earth land/sea mask is not sufficient to explore the possible variance in theoretical modeling of extrasolar planetary atmospheres.

[1] Way et al. 2017, ApJS, 231, 21 (10.3847/1538-4365/aa7a06)
[2] Mitchell et al. 2012 Nature, 482, 208-211 (10.1038/nature10800)
[3] Davies et al. 2018 Global Planetary Change, 169, 133-144 (10.1016/j.gloplacha.2018.07.015)
[4] Duarte et al. 2018 Geological Magazine, 155 (1), 45-58 (10.1017/S0016756816000716)