Description

Disclaimer: Copyright infringement not intended.

Context

Despite La Niña's typical cooling effect, January 2025 recorded unusually high temperatures, emphasizing the growing impact of global warming.

What is La Nina?

La Niña, meaning "The Little Girl" in Spanish, is a cool phase of the El Nino Southern Oscillation (ENSO).
It is characterized by colder-than-normal sea surface temperatures in the eastern Pacific Ocean.
La Nina is one of the three phases of ENSO, alongside El Nino (the warm phase) and the neutral phase.
It is the opposite of El Niño, which brings warming in the same region. Both phases significantly influence global weather patterns.

Mechanism

In La Nina, the trade winds strengthen, pushing warm water toward the western Pacific.
Cooler waters from below rise in the eastern Pacific, causing a temperature drop in that region.
La Niña occurs in irregular cycles, typically lasting from two to seven years, and often follows an El Nino event

How La Niña Affects Global Climate?

India	In India, La Nina is expected to lead to above-average monsoon rainfall from July to September, which may result in a decrease in the production of pulses in the Indo-Gangetic Plains, but rice production may see an increase.
Southeast Asia	In Southeast Asia, including Indonesia, Malaysia, and the Philippine, La Nina brings above-average rainfall, causing flooding but boosting rice and palm oil production
South America	In Southern Brazil, Uruguay, northern Argentina, and southern Bolivia, La Nina causes below-average rainfall, leading to drought and affecting soybeans and maize. In contrast, Northern Brazil, Colombia, Venezuela, and parts of Ecuador and Peru experience wetter conditions, leading to potential flooding.
Oceania	In Australia, the region experiences above-average rainfall in the northern and eastern regions, often linked to severe flooding.
Africa	In East Africa, La Nina brings drier conditions in December and January, negatively impacting crops harvested in February and March. In Southern Africa, La Nina causes above-average summer rainfall, benefiting agriculture with higher yields of maize, sorghum, wheat, and soybeans
North America	In the US, La Nina causes drier conditions in the south and wetter, stormier weather in the north, including Alaska and Canada.

Significance of La Niña for India

Agriculture: Boosts crop production due to strong monsoons, aiding farmers.

Water Resources: Improves reservoir levels, reducing water stress.

Energy: More rainfall ensures better hydropower generation.

Relief from Heat: Less severe heatwaves compared to El Niño years.

Sources:

Indian Express

PRACTICE QUESTION

Q.Consider the following statements regarding La Niña and its impact on global climate:

La Niña is characterized by cooler-than-average sea surface temperatures in the central and eastern Pacific Ocean.
La Niña typically leads to global cooling but can be overridden by anthropogenic factors.
In January 2025, La Niña significantly lowered global temperatures, counteracting the effects of climate change

Which of the statements given above is/are correct?

(a) 1 and 2 only

(b) 1 and 3 only

(d) 1, 2, and 3

Answer: (a)

Explanation:

Statement 1 is correct

La Niña is a climatic phenomenon associated with the cooling of sea surface temperatures in the central and eastern Pacific Ocean, affecting global weather patterns.

Statement 2 is Correct

La Niña generally has a cooling effect on global temperatures, but in recent years, human-induced climate change has diminished its impact.

Statement 3 is incorrect

In January 2025, despite the presence of La Niña, global temperatures remained unusually high, indicating that the effects of climate change are overpowering La Niña’s cooling influence.