The Hindu Business Line : N-E monsoon may roar back

The northeast monsoon could be just bidding time to roar into activity, if persisting and supportive El Nino trends in the equatorial Pacific are anything to go by.

The El Nino has established itself and will probably continue through the end of the calendar year and likely into the early months of 2007, said Mr Tony Barnston, Director, Forecast Operations Climate, Prediction, Dynamics, International Research Institute for Climate and Society (IRI), Columbia University.

He said the situation warranted a general alertness to an "above-average chance of systems" developing over the coming few months in the Indian Ocean system.

"The general level of storm system activity is likely to be somewhat enhanced from its normal level in regard to the northeast monsoon," he said.

The southern portions of the Arabian Sea and Bay of Bengal are likely to see positive sea-surface temperatures (SST) anomalies.

Warm seas promote the formation of potent weather systems. "The warming has already been under way in the Arabian Sea but not yet the Bay of Bengal."

The IRI threshold for El Nino conditions was exceeded in September.

The Australian Bureau of Meteorology said in its October 11 update that current Pacific climate patterns are typical for the development phase of an El Nino event.

Key indicators include SSTs above thresholds, sustained negative values of the Southern Oscillation Index (SOI), generally weaker than average trade winds since July and increased cloudiness in the central to west Pacific.

However, to qualify as an El Nino event, these key indicators would need to remain at their present levels until the year-end. There is a strong likelihood that this will occur, given what is known from previous events.

More Stories on : Climate & Weather | Climate & Weather | Outlook

Article E-Mail :: Comment :: Syndication :: Printer Friendly Page