German scientists have predicted that the Earth's temperature may stay roughly the same for a decade, as natural climate cycles enter a cooling phase.

The new computer modelling by researchers a the Leibniz Institute of Marine Sciences at Kiel University is reported in the journal Nature.

The study suggests the cooling will counter greenhouse warming, but temperatures will again be rising quickly by about 2020.

The BBC reports that the key to the new prediction is the natural cycle of ocean temperatures called the Atlantic Multidecadal Oscillation (AMO), which is closely related to the warm currents that bring heat from the tropics to the shores of Europe.

The cause of the oscillation is not well understood, but the cycle appears to come round about every 60 to 70 years. It may partly explain why temperatures rose in the early years of the last century before beginning to cool in the 1940s.

Researcher Noel Keenlyside says that one message from their study is that in the short term, you can see changes in the global mean temperature that you might not expect given the reports of the Intergovernmental Panel on Climate Change.

His group's projection diverges from other computer models only for about 15-20 years; after that, the curves come back together and temperatures rise.

"In the long term, radiative forcing (the Earth's energy balance) dominates. But it's important for policymakers to realise the pattern," he told BBC News.

The projection does not come as a surprise to climate scientists, though it may to a public that has perhaps become used to the idea that the rapid temperature rises seen through the 1990s are a permanent phenomenon.

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