Even as the debate on climate change heats up around the world, boffins ask - is it possible to predict future climate change?
Researchers at Niels Bohr Institute at the University of Copenhagen said that climate change probably occurs as a result of different chaotic influences and as a result would be difficult to predict.
The most pronounced climate shifts besides the end of the ice age is a series of climate changes during the ice age where the temperature suddenly rose 10-15 degrees in less than 10 years. The climate change lasted perhaps 1000 years, then - bang - the temperature fell drastically and the climate changed again.
This sudden change is called the tipping point and researchers have not been able to simulate it in their labs.
"We have made a theoretical modelling of two different scenarios that might trigger climate change. We wanted to investigate if it could be determined whether there was an external factor which caused the climate change or whether the shift was due to an accumulation of small, chaotic fluctuations", explained Peter Ditlevsen, a climate researcher at the Niels Bohr Institute.
According to Ditlevsen, in one scenario the climate is like a seesaw that has tipped to one side. If sufficient weight is placed on the other side the seesaw will tip - the climate will change from one state to another.
In the second scenario the climate is like a ball in a trench, which represents one climate state. Turmoil in the climate system such as storms, heat waves, heavy rainfall and the melting of ice sheets may finally push the ball over into the other trench, which represents a different climate state.
Currently, an increase in the atmospheric content of CO2 may be triggering a shift in the climate again.
"The Earth has not had such a high CO2 content in the atmosphere since more than 15 million years ago, when the climate was very warm and alligators lived in England," he said.
"This could mean that the climate might not just slowly gets warmer over the next 1000 years, but that major climate changes theoretically could happen within a few decades", Ditlevsen added, but stressed that his research only deals with investigating the climate of the past and not predictions of the future climate.
The results have just been published in Geophysical Research Letters.