Robert Taylor with David Gurarie

Analysis of Bifurcations and Abrupt Transitions in Energy Balance Models (EBM) coupled to green-house-gas emissions (GHG).

Simple energy balance models with temperature dependent albedo (reflected fraction of incoming radiation) can exhibit hysteresis and rapid transitions between “warm” and “cold” equilibrium states. Another important factor that affects radiative balance and mean temperature are greenhouse gases (GHG) that control outgoing radiation. They have multiple sources and sinks, natural and anthropogenic (man-made), and temperature could also affect those processes. We will develop and explore a coupled EBM + GHG dynamic model with temperature feedbacks linked to albedo and GHG. Our goal is to study possible tipping points (abrupt transitions) and hysteresis cycles in such systems. We shall also explore different inputs and control parameters that could affect abrupt transitions, like anthropogenic GHG emissions or frozen methane deposits. The models will include globally average (“zero-dimensional”) EBM, and zonally average  1D EBM, and focus on CO2 and methane GHG