El Nino has arrived: What is Indian Ocean Dipole that can save monsoon?
How or if the Indian Ocean Dipole develops remains to be seen. However, if one looks at history, the climate phenomenon does offer hope.
El Nino has officially arrived, reviving fears of weaker monsoon rains and hotter-than-normal conditions across India.
This El Nino, which had been predicted to arrive by numerous weather agencies, could potentially be a historic one, with impacts lasting well until next year.
The climate phenomenon has historically been associated with droughts and rainfall deficits, and hot and dry conditions, making its return a concern for a country where millions depend on the rain to find relief from heat, and grow crops to earn a living.
But meteorologists are also keeping a close eye on another ocean phenomenon that could help balance things out.
Known as the Indian Ocean Dipole (IOD), the climate pattern has, in the past, countered the adverse effects of El Nino and helped India avoid severe monsoon shortfalls.
That fact alone raises questions about what it is and how it can help.
WHAT IS INDIA OCEAN DIPOLE?
The Indian Ocean Dipole, or IOD, refers to the difference in sea-surface temperatures between the western and eastern Indian Ocean.
Scientists classify the phenomenon into three phases; positive, negative and neutral. Unlike El Nino, which develops over the Pacific Ocean, the IOD forms in the Indian Ocean and directly influences weather across countries surrounding it.
During a positive IOD event, waters near the African coast become warmer than usual while waters around Indonesia turn relatively cooler. This temperature contrast changes wind patterns and channels more moisture towards India, often boosting rainfall.
At present, the IOD remains in a neutral phase, although Japan's Meteorological Agency (JMA) said that it expects a positive IOD to develop later this year.
JMA was also the first major weather agency across the globe to announce the arrival of El Nino.
CAN INDIAN DIPOLE HELP AGAINST EL NINO?
How or whether the IOD develops remains to be seen. But if one looks at history, the climate phenomenon does offer hope.
History shows that a positive IOD can soften the impact of El Nino on India’s monsoon.
One of the clearest examples came in 1997. Despite one of the strongest El Nino events on record that year, India avoided a severe rainfall deficit because a strong positive IOD developed at the same time.
That is why scientists are closely watching the Indian Ocean this year.
However, they caution that a positive IOD does not guarantee abundant rainfall, as its timing and intensity determine how much support it can provide.
There are currently various pieces moving, and they will all have to align for the worst outcome to be avoided. And it's imperative that they do, because India's already delayed monsoon is an imperative season.
The southwest monsoon delivers nearly 70% of India’s annual rainfall and remains vital for agriculture, reservoirs and food security.
With serious shortfalls, the world's most populous country could face cascading impacts, like widespread droughts, crop losses, and acute water shortages.
As El Nino strengthens, attention will increasingly turn to the Indian Ocean to see if the IOD shifts into a positive phase in the coming months. If it does, it could provide a much-needed cushion and help keep the monsoon on track.
El Nino has officially arrived, reviving fears of weaker monsoon rains and hotter-than-normal conditions across India.
This El Nino, which had been predicted to arrive by numerous weather agencies, could potentially be a historic one, with impacts lasting well until next year.
The climate phenomenon has historically been associated with droughts and rainfall deficits, and hot and dry conditions, making its return a concern for a country where millions depend on the rain to find relief from heat, and grow crops to earn a living.
But meteorologists are also keeping a close eye on another ocean phenomenon that could help balance things out.
Known as the Indian Ocean Dipole (IOD), the climate pattern has, in the past, countered the adverse effects of El Nino and helped India avoid severe monsoon shortfalls.
That fact alone raises questions about what it is and how it can help.
WHAT IS INDIA OCEAN DIPOLE?
The Indian Ocean Dipole, or IOD, refers to the difference in sea-surface temperatures between the western and eastern Indian Ocean.
Scientists classify the phenomenon into three phases; positive, negative and neutral. Unlike El Nino, which develops over the Pacific Ocean, the IOD forms in the Indian Ocean and directly influences weather across countries surrounding it.
During a positive IOD event, waters near the African coast become warmer than usual while waters around Indonesia turn relatively cooler. This temperature contrast changes wind patterns and channels more moisture towards India, often boosting rainfall.
At present, the IOD remains in a neutral phase, although Japan's Meteorological Agency (JMA) said that it expects a positive IOD to develop later this year.
JMA was also the first major weather agency across the globe to announce the arrival of El Nino.
CAN INDIAN DIPOLE HELP AGAINST EL NINO?
How or whether the IOD develops remains to be seen. But if one looks at history, the climate phenomenon does offer hope.
History shows that a positive IOD can soften the impact of El Nino on India’s monsoon.
One of the clearest examples came in 1997. Despite one of the strongest El Nino events on record that year, India avoided a severe rainfall deficit because a strong positive IOD developed at the same time.
That is why scientists are closely watching the Indian Ocean this year.
However, they caution that a positive IOD does not guarantee abundant rainfall, as its timing and intensity determine how much support it can provide.
There are currently various pieces moving, and they will all have to align for the worst outcome to be avoided. And it's imperative that they do, because India's already delayed monsoon is an imperative season.
The southwest monsoon delivers nearly 70% of India’s annual rainfall and remains vital for agriculture, reservoirs and food security.
With serious shortfalls, the world's most populous country could face cascading impacts, like widespread droughts, crop losses, and acute water shortages.
As El Nino strengthens, attention will increasingly turn to the Indian Ocean to see if the IOD shifts into a positive phase in the coming months. If it does, it could provide a much-needed cushion and help keep the monsoon on track.
