The India Meteorological Department (IMD) has predicted that, except for specific areas in the northwest and west-central regions, most parts of India will experience above-normal minimum temperatures in November.
The El Nino conditions are expected to persist throughout the season, while the positive Indian Ocean Dipole conditions are likely to weaken in November.
India Meteorological Department (IMD) Findings
- Currently, there are two weather phenomena happening over the oceans - El Nino in the Equatorial Pacific and Indian Ocean Dipole in the Indian Ocean.
- El Nino is characterized by warmer Pacific waters near South America, which can cause weaker monsoon winds and drier weather in India.
- Indian Ocean Dipole is the difference in sea surface temperatures between the western and eastern parts of the Indian Ocean.
- According to global forecasts, El Nino is expected to continue, while the Indian Ocean Dipole is expected to weaken in the coming months.
- As for rainfall, some areas of southern peninsular India, northwest India and east-central, east and northeast India are likely to receive above-normal rainfall.
- However, the northeast monsoon season in south India, which began in October, has been the sixth lowest since 1901, and there is a tendency for the rainfall to be delayed in Tamil Nadu and nearby areas.
India’s West Coast receives Rainfall from the South West Monsoon whereas the East Coast including Tamil Nadu receives rainfall from the North West Monsoon.
What is El Niño?
South American fishermen first noticed periods of unusually warm water in the Pacific Ocean in the 1600s.
During El Niño, the trade winds weaken, which causes warm water to be pushed back east, towards the west coast of the Americas.
El Niño is a Spanish term that means "Little Boy". It usually occurs around Christmas.
El Nino impact on Asia including India
- The air rises and the surface air pressure over the Eastern Pacific decreases as a result of this warm water. On the other side, the temperatures cool off Asia and the western Pacific.
- Increased surface pressure results from this over the Indian Ocean, Australia and Indonesia. Therefore, as high pressure accumulates over the cool ocean waters, the drought begins to spread throughout Asia while it is raining in the Eastern Pacific.
- El Nino negatively impacts India's agriculture and its monsoon season, while also creating challenges for seabirds and marine mammals during breeding and survival.
El Nino Impact on East Pacific
- The occurrence of El Niño has a significant impact on the marine life present off the coast of the Pacific Ocean.
- During normal conditions, upwelling brings water from the depths to the surface, which is cold and nutrient-rich. During El Niño, the process of upwelling tends to weaken or stop completely.
- As a result, the nutrients from the deeper parts of the ocean become scarce, leading to a decrease in the amount of phytoplankton off the coast. This, in turn, has a direct impact on species of fish that depend on phytoplankton as their food source, which consequently affects the entire food chain.
- Additionally, the warmer waters during El Niño can attract tropical species such as yellowtail and albacore tuna, which are normally found in areas with warmer temperatures.
What is La Niña?
La Niña, which means Little Girl in Spanish, is a weather phenomenon that is sometimes referred to as El Viejo, anti-El Niño, or simply "a cold event." La Niña has the opposite effect of El Niño, and during La Niña events, trade winds are even stronger than usual, which pushes more warm water toward Asia.
La Nina impact on East pacific including America
- The upwelling increases off the west coast of the Americas, bringing cold and nutrient-rich water to the surface.
- The cold waters in the Pacific Ocean cause the jet stream to move northward, resulting in droughts in the southern United States and heavy rainfall and flooding in the Pacific Northwest and Canada.
- During La Niña, the waters off the Pacific coast are colder and contain more nutrients than usual, which creates an environment that is conducive to supporting more marine life and attracting more cold-water species, such as squid and salmon, to places like the California coast.
- In a La Niña year, winter temperatures are warmer than usual in the southern region and cooler in the northern region. Additionally, La Niña can contribute to a more severe hurricane season.
Drought in Peru and Ecuador, severe flooding in Australia, high temperatures in the West Pacific, Indian Ocean, off the coast of Somalia, and abundant monsoon rains in India are all effects of La Nina. The Indian monsoon benefits from a La Nina.