La Nina: Impact on Monsoon and steps to fight the impact.

 La Nina :- 

La Niña, “anti-El Niño” or simply “a cold event” is the cooling of water in the Eastern Pacific Ocean.

Sequence of events :- 

• The water in Eastern Pacific, which is otherwise cool; gets colder than normal. There is no reversal of the trade winds but it causes strong high pressure over the eastern equatorial Pacific.
• On the other hand, low pressure is caused over Western Pacific and Off Asia.
• This has so far caused the following major effects: Drought in Ecuador and Peru. Low temperature, High Pressure in Eastern Pacific
• Heavy floods in Australia; High Temperature in Western Pacific, Indian Ocean, Off coast Somalia and good rains in India. Drought in East Africa.

Impact on Domestic Monsoon :- 

For India, an El Niño is often a cause for concern because of its adverse impact on the south-west monsoon; this happened in 2009. A La Niña, on the other hand, is often beneficial for the monsoon, especially in the latter half. The La Niña that appeared in the Pacific in 2010 probably helped 2010’s south-west monsoon end on a favorable note. However, it also contributed to the deluge in Australia, which resulted in one of that country’s worst natural disasters with large parts of Queensland either under water from floods of unusual proportions or being battered by tropical cyclones.

Recurrance :- 

his distortion is pressure and temperature recurs every 4-5 years. But it may not happen exactly after 4-5 years or it may not happen at all. It periodicity is thus quite uncertain.

El Nino and La Nina episodes typically last nine to 12 months, but some prolonged events may last for years. They often begin to form between June and August, reach peak strength between December and April, and then decay between May and July of the following year. While their periodicity can be quite irregular, El Nino and La Nina events occur about every three to five years. Typically, El Nino occurs more frequently than La Nina.

Relationship between El nino , La Nina and Indian draught and monsoons :- 

Looking at the relation between El Nino and Indian droughts since 1950, it is observed that India faced 13 droughts and 10 of these were in El Nino years and one in a La Nina year. This indicates there may not be a one-to-one correspondence between El Nino and Indian droughts.

Overall, the analysis proves that since the 1980s, only El Nino years converted into droughts for India and its states. However, a La Nina year does not guarantee better-than-normal rains and similarly
an El Nino year does not always translate into below-normal rains.

Mitigation Steps :- 

• The government must expand the farm insurance cover and advice banks and financial institutions to settle crop insurance claims in the drought-hit areas without delay.
• High quality seeds of alternative crops must be distributed among farmers in the drought-affected areas.
• Realistic assess the ground level situation in order to estimate the shortfall of oilseeds and pulses and help traders with market intelligence.
• Bringing down the cereals’ inflation by liquidating the extra stock it was holding, which is way above the buffer requirement.
• Modifying the APMC Act to allow free flow of agriculture goods among the states. This would help bridge the mismatch of demand and supply of goods, which is the underlying factor contributing inflation.
• Using low water use technologies like drip and sprinkler irrigation.
• Moving away from water intensive crops to less water consuming crops

By: Shashank Shekhar