Climate Bistability of Terrestrial Exoplanets

This seminar is part of the EAI on-line seminars

By Antonello Provenzale, CNR, Italy

22 September 2020, 16:00 CET

Planetary climates are complex systems that include a multitude of stabilizing (negative) and destabilizing (positive) feedback loops. One of them, the ice-albedo feedback, is thought to be responsible for the existence of multiple stable states of the Earth’s climate, with the alternation between ice-covered conditions (the most extreme being the so-called Snowball) and warm states. Here, we explore the possible presence of bistability in the climate of Earth-like planets, using a simple one-dimensional climate model called ESTM.
During the seminar, we will consider the role of ice-albedo feedback for a wide range of orbital and planetary parameters such as distance from the star, ellipticity, obliquity and atmospheric pressure. Other possible mechanisms for bistability will also be mentioned, such as the vegetation-albedo and the vegetation-moisture feedbacks. Implications on planetary habitability will finally be discussed.