El Nino & the Indian Monsoon

Indications of an El Nino phenomenon developing in August-September grew stronger with Australia’s weather bureau saying that most climate models were pointing to the appearance of the anomaly.  El Nino is the name given to an unusual warming of the ocean surface around the equatorial Pacific. The phenomenon is often associated with bad southwest monsoons in India. 
Australia’s bureau of meteorology said though temperatures in the tropical Pacific were still within normal range, the ocean was slowly warming up. “The majority of the (climate) models indicate that the tropical Pacific will approach or possibly exceed El Nino thresholds by 
the end of winter (August),” the update said.
The Australian update appears to indicate the onset of El Nino conditions more than a forecast released on June 11 by the US National Oceanic and Atmospheric Administration, which put the chances of the phenomenon taking 
place at 50%. El Nino conditions are said to occur when the monthly average temperature of the ocean surface is at least 0.5°C above normal. 
If an El Nino does develop in August-September, it could affect the second half of the monsoon. Sources said IMD would be factoring in this pos
sibility when it updates this year’s monsoon prediction later this week. 
As of now, the monsoon was 25% below normal with 61% of the country’s area receiving deficient rains since June 1. Most experts, however, say the monsoon’s poor start is no indication of how it would perform in the coming months. 
El Nino’s last occurrence in 2009 coincided with the worst monsoon in India in almost 40 years. Before that a weak El Nino occurred in 2002, which again was a drought year in India after 14 good monsoons. 
However, all El Nino episodes are not linked with failure of the Indian monsoon. For instance, the strongest El Nino in recent time occurred in 1997 but it failed to depress monsoon rains that year.

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