Q. Consider the following statements regarding the El-Niño phenomenon:
1.El-Niño is associated with the replacement of the cold Peruvian (Humboldt) current by a warm equatorial current off the coast of Peru.
2.It leads to a rise in sea surface temperature, which reduces plankton availability and affects fish populations.
3.In India, El-Niño events have no impact on the timing of the southwest monsoon.
Which of the statements given above is/are correct?
Answer: A
Notes:
Explanation:
- El-Niño is a climatic phenomenon characterized by the replacement of the cold Humboldt (Peruvian) current with a warm equatorial current in the Pacific Ocean, especially off the coast of Peru and Ecuador. This disrupts the normal upwelling of nutrient-rich cold water, significantly altering weather patterns.
- The rise in sea surface temperatures during El-Niño inhibits the upwelling of nutrient-rich water, leading to a drop in plankton population, which forms the base of the marine food chain. As a result, fish populations, especially anchovies, decline drastically, affecting fisheries.
- El-Niño does impact the Indian southwest monsoon, typically leading to weaker monsoon rains and, in some cases, drought-like conditions.
Source: India Physical Environment (Class 11th NCERT)
