Climate Modelling Part 2


Earth System Models (ESMs) are climate models which in addition to physical processes also simulate a range of relevant biogeochemical cycles, e.g. the carbon cycle, dynamical vegetation, atmospheric aerosols and chemistry. Relative to conventional purely physical coupled atmosphere-ocean General Circulation Models (GCMs), ESMs include many more process representations, variables, and also climate relevant feedbacks on both short - instantaneous to few years - as well as long - decades to centuries and millennia - time scales. ESMs are continuously expanding to include further processes. For example, the ESMs participating in the Coupled Model Intercomparison Project Phase 6 (CMIP6) for the first time include interactive ice sheets and several models have interactive chemistry and aerosols. ESMs are common tools to understand and project climate change and can also contribute to the design of feasible mitigation pathways for example through the computation of allowable emissions for a specific temperature target. This block course provides an overview of selected components of ESMs and explains the underlying basics and the numerical formulation of the fundamental equations. In addition, topics such as Earth system projections and climate change, evaluation of ESMs with observations, and climate informatics are covered. Selected areas of current research activities and results from ESMs participating in CMIP are presented. The block course also includes computational exercises with the Earth System Model Evaluation Tool (ESMValTool, that is developed to facilitate routine and comprehensive evaluation of ESMs with observations as well as a hands-on machine learning session. The goal of this block course is that you get a broad overview of how an Earth system model works (without covering all details) and learn about results of current models regarding climate change, and that you get some first experience how to analyse Earth system model output with the ESMValTool and with machine learning.

Topics to be addressed:

Components of Earth System Models (ESMs); Fundamentals and representation in ESMs: carbon cycle, atmospheric chemistry, and aerosols; Earth system model evaluation with observations; Earth system feedbacks and projections; Understanding and modelling the Earth System with Machine Learning; Computational exercises with the Earth System Model Evaluation Tool (ESMValTool) and interpretation of ESM results; Computational exercises “hands-on Machine Learning”.


1. Brasseur & Jacob, Modeling of Atmospheric Chemistry, 2016
2. Gettelman & Rood, Demystifying Climate Models, 2016
3. Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report, 2013
4. Jacobson, Fundamentals of Atmospheric Modeling, 2005
5. McGuffie & Henderson-Sellers, A Climate Modelling Primer, 2013
6. World Meteorological Organization (WMO) / United Nations Environment Programme (UNEP)
Scientific Assessment of Ozone Depletion