Tracing the Snowball bifurcation of aquaplanets through time reveals a fundamental shift in critical-state dynamics ...

• Main Authors: Feulner, Georg, Bukenberger, Mona, Petri, Stefan
• Format: Text
• Language: English
• Published: Göttingen : Copernicus 2023
• Subjects: Bifurcation mathematics; Carbon dioxide; Dynamics; Earth planet; Earth system models; Glacial geology; Luminance; Sea ice; Solar energy; Thermal gradients; Atmospheric concentration; Climate system; CO2 concentration; Critical CO2; Critical-state; Fundamental properties; Ice albedo feedback; Meridional temperature gradient; Solar-luminosity; State dynamics; atmospheric chemistry; bifurcation; carbon dioxide; carbon emission; chemical composition; concentration composition; snow cover; trace element; Climate models; 550
• Online Access: https://dx.doi.org/10.34657/13714; https://oa.tib.eu/renate/handle/123456789/14692

The instability with respect to global glaciation is a fundamental property of the climate system caused by the positive ice-albedo feedback. The atmospheric concentration of carbon dioxide (CO2) at which this Snowball bifurcation occurs changes through Earth's history, most notably because of the slowly increasing solar luminosity. Quantifying this critical CO2 concentration is not only interesting from a climate dynamics perspective but also constitutes an important prerequisite for understanding past Snowball Earth episodes, as well as the conditions for habitability on Earth and other planets. Earlier studies are limited to investigations with very simple climate models for Earth's entire history or studies of individual time slices carried out with a variety of more complex models and for different boundary conditions, making comparisons and the identification of secular changes difficult. Here, we use a coupled climate model of intermediate complexity to trace the Snowball bifurcation of an aquaplanet ...