La Niña is the cold stage of the El Niño Southern Oscillation (ENSO) cycle. It happens because of the temperature shift between the ocean and the atmosphere in the Pacific. La Niña results in a powerful trade wind push, which increases the temperature of the water westward. The push allows colder water from the deep ocean to rise near South America’s coast. This change outcomes in cooling the central and eastern Pacific by changing weather patterns around the world.
Meteorologists from the U.S. National Oceanic and Atmospheric Administration (NOAA) have declared that ocean surface temperatures have cooled down enough to signal the arrival of La Niña.
How does it affect global weather?
According to SmartNews, La Niña turns the global weather more volatile. It often strengthens monsoons in Asia, which results in an increase in the rainfall in countries like India, Indonesia, and the Philippines. Australia will be witnessing a spring and early summer characterised by rainfall, which can lead to an alarming risk of flooding in low-lying regions. The southern regions of US normally experience drier and warmer conditions, whereas the northern states will experience colder and snowier conditions. In contrast, South America could experience droughts in Chile and Argentina but receive heavy rainfall in the countries of Colombia and Brazil.
Why it matters now
According to SmartNews, La Niña is characterised by one of the warmest El Niño years on record. Scientists warn that the transition could result in intensifying extreme temperatures and could cause harm to the agricultural cycles. Crops such as wheat, coffee, and rice are highly sensitive to changes in rainfall patterns. This could impact the global food supply.
Environmental experts also warn that La Niña can temporarily cool international average temperatures, potentially developing a deceitful sense of “climate relief” despite the ongoing tendency of global warming.
The coming of La Niña signals a new chapter in Earth’s climate rhythm. It is the condition that will test stability and adaptation across sectors. While it might carry cooler conditions in some regions, it also promises increased weather volatility.