Climate models are computer programs which simulate the climate or weather patterns over time. They can be used to estimate the Earth’s climate under different conditions by running simulations.

Climate models are powerful tools for simulating, analysing and understanding the Earth’s climate. They are used to understand how our planet is changing and are fundamental to climate science.

They help us understand how the climate is affected by emissions, economic growth, technological developments, and political and social change. They can be used to represent possible futures depending on the decisions we make now.

The elements of climate models. Source: Adapted from the IPCC.

A model is a simplified description of a system or process which helps us understand how a system works or behaves. Models can be as simple as toy cars or as complex as flight simulators and climate models.

The climate system is complex, made up of varying factors such as rain, wind, temperature, humidity, and solar radiation. Climate models represent the climate through mathematical equations describing the physics, chemistry and biology of each component of the climate and how they interact e.g., the movement of the air in the atmosphere, or the exchange of moisture between the ocean, land and atmosphere.

A climate model is a tool used to understand how the different components of the earth’s climate interact and are changing. The complex nature of the climate system is hard to represent. Climate models allow us to test ideas and measure how our actions or decisions will change the climate in the future. For example, what happens when we increase greenhouse gas emissions, or revegetate landscapes?

Many years of development and evaluation enable climate models to simulate seasonal and annual cycles of weather systems and how they will change into the future. This skill allows us to make projections of future temperature and rainfall in different geographic locations.