2018/10/31 by Tiffany Jansen, Caleb Scharf, Michael Way +1 · 1 citation
Physics and Astronomy · #astro-ph.EP
paper · pdf · doi:10.3847/1538-4357/ab113d
11 pages, 10 figures, accepted for publication in ApJ
arxiv created 2020/03/30 · arxiv updated 2020/04/01
Planetary rotation rate has a significant effect on atmospheric circulation, where the strength of the Coriolis effect in part determines the efficiency of latitudinal heat transport, altering cloud distributions, surface temperatures, and precipitation patterns. In this study we use the ROCKE-3D dynamic-ocean general circulation model to study the effects of slow rotations and increased insolations on the 'fractional habitability' and silicate weathering rate of an Earth-like world. Defining the fractional habitability fh to be the percentage of a planet's surface which falls in the 0 <= T <= 100 C temperature regime, we find a moderate increase in fh with a 10% and 20% increase in insolation and a possible maximum in fh at sidereal day-lengths between 8 and 32 times that of the modern Earth. By tracking precipitation and run-off we further determine that there is a rotational regime centered on a 4-day period in which the silicate weathering rate is maximized and is particularly strongly peaked at higher overall insolations. Because of weathering's integral role in the long-term carbonate-silicate cycle, we suggest that climate stability may be strongly affected by the anticipated rotational evolution of temperate terrestrial-type worlds, and should be considered a major factor in their study. In light of our results we argue that planetary rotation period is an important factor to consider when determining the habitability of terrestrial worlds.