The Met Office Hadley Centre uses complex computer models of the atmosphere, land and ocean systems to make predictions of future climate change, including temperature. These models are mathematical representations of the climate system and are based on the fundamental laws of physics.
The models are tested and evaluated against actual observations on a number of time scales, ranging from palaeoclimate to day to day weather. Model performance and improvement is aided because the Met Office uses the same model framework for its climate projections as it does for weather forecasting.
In addition to its own models, the Met Office Hadley Centre makes use of climate models from the global scientific community. These are used for comparison and can aid improvement to Met Office models. The methods employed in the development of Met Office models are thoroughly and independently reviewed in the peer-reviewed literature.