  The climate is a non-equilibrium system undergoing the continuous action of
forcing and dissipation. Under the effect of a spatially inhomogeneous
absorption of solar energy, all the climate components dynamically respond by
redistributing energy until an approximate steady state is reached. In order to
improve the skill of climate models and correct their biases, it is essential
to investigate how such dynamical balance is reached. In general, the climate
system features multiple steady states for a given set of boundary conditions.
Here, we apply the Thermodynamic Diagnostic Tool (TheDiaTo) to investigate the
statistical properties of the five co-existing climates, ranging from a
snowball to an ice-free aquaplanet, obtained in MITgcm coupled simulations
under the same boundary conditions. The aim is to explore the multistability of
the climate by highlighting differences in competing steady states and their
characteristic signatures regarding the meridional transport of heat and water
mass, the Lorenz energy cycle and the material entropy production. Alternative
cloud parametrizations and descriptions of energy exchange are also used to
investigate how robust such signatures are and, at the same time, how the
statistical properties can be improved in the simulated climatic states. Thus
we show how the diagnostic tool can help in identifying strengths and
weaknesses of a model configuration.
