What are EMICs?

In the classification of climate models there exists three basic categories within which all models are classified. These are EBMs, GCMs, and EMICs. Energy balance models are usually algebraic and demonstrate simple one-dimensional phenomena. For instance, the heat absorbed by the ground when light hits it. Modeling this scenario with the stefan-boltzmann equation and basic geometry yields a simple algebraic equation, which counts as a climate model! On the other side of the spectrum, exists GCMs, Global Circulation Models, which attempt to simulate every climate process in as much detail as possible. These types of models deserve an encyclopedia unto themselves, and represent the state-of-the-art in climate modeling. They are used to make the planet’s best predictions about the future of our climate.

Between these two classifications lies EMICs or Earth Models of Intermediate Complexity. EMICs are many things. There is not one thing that defines an EMIC, save for its placement between EBMs and GCMs on the scale of complexity and size. EMICs represent an affordable and accessible way for smaller researchers to begin modeling climate. At the same time, their efficient run times make them the only tools available to climate researchers looking to simulate long term climate. GCMs, for example, are not able to answer the question, what will the earth look like in 10,000 years?

EMICs take many shapes and forms, they can be coarse resolution global climate models or high resolution regional climate models. Their existence can be seen as a way to satisfy a niche not fulfilled by the GCMs or EBMs, in any way this niche or need may present itself. Because of this amorphous definition, EMICs represent a diverse classification of climate models, and an increasingly important one. Many of the predictions made in the IPCC report are based on EMIC model results, GCMs are just too expensive to run in every scenario.