Whole planet coupling between climate, mantle, and core: Implications for rocky planet evolution

Abstract

Earth's climate, mantle, and core interact over geologic timescales. Climate influences whether plate tectonics can take place on a planet, with cool climates being favorable for plate tectonics because they enhance stresses in the lithosphere, suppress plate boundary annealing, and promote hydration and weakening of the lithosphere. Plate tectonics plays a vital role in the long-term carbon cycle, which helps to maintain a temperate climate. Plate tectonics provides long-term cooling of the core, which is vital for generating a magnetic field, and the magnetic field is capable of shielding atmospheric volatiles from the solar wind. Coupling between climate, mantle, and core can potentially explain the divergent evolution of Earth and Venus. As Venus lies too close to the sun for liquid water to exist, there is no long-term carbon cycle and thus an extremely hot climate. Therefore plate tectonics cannot operate and a long-lived core dynamo cannot be sustained due to insufficient core cooling. On planets within the habitable zone where liquid water is possible, a wide range of evolutionary scenarios can take place depending on initial atmospheric composition, bulk volatile content, or the timing of when plate tectonics initiates, among other factors. Many of these evolutionary trajectories would render the planet uninhabitable. However, there is still significant uncertainty over the nature of the coupling between climate, mantle, and core. Future work is needed to constrain potential evolutionary scenarios and the likelihood of an Earth-like evolution.

Assessing the Intrinsic Uncertainty and Structural Stability of Planetary Models: 1. Parameterized Thermal‐Tectonic History Models

“…These models are efficient for traversing vast regions of parameter space (McNamara & Van Keken, ). They also allow layers of complexity to be added to base level models in relatively simple and efficient ways, for example, deep water cycling (McGovern & Schubert, ; Sandu et al, ), planetary carbon cycling (Abbot et al, ; Franck & Bounama, ; Tajika & Matsui, , ; Sleep & Zahnle, ; Sleep et al, ), coupled thermal evolution, and climate modeling (Foley, ; Foley & Driscoll, ; Jellinek & Jackson, ; Lenardic et al, ). They can also be scaled to different planetary mass and/or volume in ways that maintain model efficiency (Valencia et al, ).…”

“…Input/parameter uncertainty is generally evaluated in thermal history studies (e.g., Christensen, ; Davies, ; Korenaga, ) and in studies that couple thermal history models to climate models (e.g., Driscoll & Bercovici, ; Foley & Driscoll, ; Rushby et al, ). Intrinsic uncertainty has not, to the best of out knowledge, been evaluated for thermal history models.…”

“…Determining/mapping particular and/or potential planetary cooling paths is the goal of thermal history modeling (Davies, 1980;Schubert et al, 1980). Thermal Input/parameter uncertainty is generally evaluated in thermal history studies (e.g., Christensen, 1984;Davies, 1980;Korenaga, 2003) and in studies that couple thermal history models to climate models (e.g., Driscoll & Bercovici, 2013;Foley & Driscoll, 2016;Rushby et al, 2018). Intrinsic uncertainty has not, to the best of out knowledge, been evaluated for thermal history models.…”

Mars: a small terrestrial planet

“…Coupling between atmosphere, crust, mantle, and core evolution has been well documented for the Earth, as a system, and is an important feature of all rocky planets (Foley and Driscoll 2016). The volatile concentrations of the mantle source and the volume of magma reaching the surface (effusion rate) determine the amount of volatile species that have been released in the atmosphere as a function of time.…”

Detectability of Remanent Magnetism in the Crust of Venus

“…Unfortunately, the statement that Venusian surface temperatures are too high to preserve TRM in common minerals is prevalent in the literature (Breuer et al, 2010;Luhmann & Russell, 1997;Russell, 1993;Russell et al, 1980) and thus popular conception (e.g., Taylor, 2014). Recent studies may acknowledge a chance of preserving crustal remanence but assert that detectable signals are unlikely at best because any crustal fields would be very weak (Breuer & Moore, 2015;Foley & Driscoll, 2016;Schubert & Soderlund, 2011).…”