Climate models

Climate models are sets of mathematical equations that are used to attempt to understand and predict the evolution of the climate of the Earth and other planets.

The most comprehensive, state-of-the-art climate models seek to describe how climate changes over time, in as much detail and with as much accuracy as possible. Such models require large supercomputers to run. There are also very simple climate models, however, that are easy to solve and can help us form basic expectations for how climate will behave under different conditions.

Some of the equations that govern climate dynamics have been known for a very long time. The equations of fluid dynamics, for example, have been known for over one hundred years, and are associated with the complex patterns of flow seen in the Earth’s atmosphere and oceans. Other equations, such as those associated with cloud formation or the behaviour of plants are poorly understood or even unknown. Approximations must be made when it is necessary to predict the behaviour of the relevant processes, meaning that climate predictions are fundamentally uncertain. One response to this problem has been to run large numbers of similar climate models with different approximations of poorly understood processes, to see how the uncertainty impacts on climate predictions.

As we show in the exhibition, climate model simulations are performed for planets other than Earth to understand their climates. A second important reason for studying exoplanet climates is that the equations of climate dynamics are believed to be the same for Earth and other planets. Because the conditions on different planets can be very different, we can test our understanding in a very wide range of scenarios, allowing us to learn new things about climate processes and our ability to model them.

Find out more about climate models on the Met Office website, and more about climate dynamics on the next page.