Scientists have, for the first time, demonstrated that climate models are able to simulate past abrupt changes in the Earth’s climate– giving more confidence in predictions of future global climate change.
The study, which was published this month in the scientific journal PNAS, was led by Professor Sybren Drijfhout, who is head of the Physical Oceanography Group at the University of Southampton. The team interrogated a state-of-the-art climate model, and found that it is able to recreate an abrupt cooling event similar to the "Little Ice Age" by taking into account the ocean, atmosphere and sea ice components of the climate system.
This capability exhibited by the model implies that scientists can be more confident about predicting rapid climatic changes in the future.
Global climate has fluctuated throughout Earth’s history, driven by natural variability in Earth systems and external forcing. Clues from the geological record have allowed scientists to detect abrupt transitions between different climate states, but until now they have not been able to recreate them in computer models of past climates.
“Scientists have argued that we cannot trust climate models if they are unable to reproduce abrupt climate switches which have occurred in the past,” says Drijfhout, who is based at the National Oceanography Centre, Southampton (NOCS) and is also affiliated with the Royal Netherlands Meteorological Institute. “The new generation of climate models have made an important leap forward– we are now more confident that if abrupt changes in the Earth’s climate are to happen in the future, our current generation of climate models will be able to predict them.”
Drijfhout is now working with colleagues from the European project EMBRACE to analyze these climate events in more detail.
The climate model investigated in the study is the EC-Earth model, developed by a consortium of European countries together with the European Centre for Medium-range Weather Forecasts in Reading.