How exactly do climate models work?

One key way for natural scientists to understand complex processes is to reproduce them in computer models. In recent decades, climate research has developed increasingly detailed models of the Earth’s climate system, which correctly predicted the current warming trend as early as the 1970s and 1980s.

The rise in global temperature is currently proceeding within the range that the Intergovernmental Panel on Climate Change (IPCC) expected in its first Assessment Report in 1990. Other predictions made by earlier climate models were later confirmed by actual developments, for example with regard to glacier melt, the rise in sea levels, and an increase in droughts.¹ However, climate models are unable to provide accurate weather forecasts for the distant future (nor were they developed for that purpose).
Modern climate models have therefore repeatedly proved that they can accurately reproduce actual climate-related developments. As a result, inferences that we can make today about how the climate will develop in the future as based on the findings of model calculations provide a reliable basis for political decisions.