Scientists blame warmer Atlantic for wet summers

Britain experienced one of its rainiest summers in a
century

Recent warming in the Atlantic Ocean is the main cause of wet summers in northern Europe, according to a new study.

A cyclical pattern of rising and falling ocean temperatures is seen as a major influence on our weather.

Scientists say the current pattern will last as long as the Atlantic warming persists.

The research was carried out at the University of Reading and is published in the journal Nature Geoscience.

The study investigated a phenomenon known as the Atlantic Multidecadal Oscillation - a cycle of change in which the waters either warm or cool over a period of several decades.

The researchers compared three periods in this cycle: a warm state from 1931-60, a cool period from 1961-90 and the most recent warm period starting in 1990 and continuing now.

The paper notes that conditions in the last warm period in the Atlantic are broadly similar to those observed now.

So the study compared weather conditions in Europe during the two warm Atlantic phases with those experienced in the cool phase.

One conclusion is that a warmer-than-usual Atlantic "favours a mild spring (specially April), summer and autumn, in England and across Europe."

Another finding - of greatest relevance to the search for a cause of rainy summers - is that the warmth of the ocean also tends to make northern and central Europe wetter than usual. By contrast southern Europe, from Portugal to Turkey, gets far less rain than normal.

That was the pattern observed last summer.

-  BBC.co.uk