British scientists have found an unexpected link between Asian monsoons and an oscillating pattern of Indian Ocean sea surface temperatures.
Nerilie Abram and colleagues at the British Antarctic Survey say their findings suggest the consequences of future Asian monsoons will be more widespread and intense than previously forecast.
The recently discovered Indian Ocean Dipole, as it is known, has profound impacts on rainfall across the tropical Indian Ocean region. But its interactions with the Asian monsoon system and El Nino/Southern Oscillation -- which are themselves forecast to change -- have been unclear.
Abram and his colleagues used coral records to reconstruct the interaction for the past 6,500 year -- including times when the Asian monsoon season behaved very differently from how it does today.
The results, the scientists say, show the dipole does not act in isolation but is influenced by the Asian monsoon, which appears to extend dipole-related droughts and sea-surface cooling.
The study is detailed in the current issue of the journal Nature.
Copyright 2007 by United Press International
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