New! Sign up for our free email newsletter.
Reference Terms
from Wikipedia, the free encyclopedia

El Niño-Southern Oscillation

El Niño-Southern Oscillation (ENSO) is a global coupled ocean-atmosphere phenomenon. The Pacific ocean signatures, El Niño and La Niña (also written in English as El Nino and La Nina) are major temperature fluctuations in surface waters of the tropical Eastern Pacific Ocean. The names, from the Spanish for "the little boy" and "the little girl", refer to the Christ child, because the phenomenon is usually noticed around Christmas time in the Pacific Ocean off the west coast of South America. Their effect on climate in the southern hemisphere is profound. These effects were first described in 1923 by Sir Gilbert Thomas Walker from whom the Walker circulation, an important aspect of the Pacific ENSO phenomenon, takes its name. The atmospheric signature, the Southern Oscillation (SO) reflects the monthly or seasonal fluctuations in the air pressure difference between Tahiti and Darwin. El Nino affects Australia by drought.

Related Stories
 


Earth & Climate News

April 19, 2026

Human societies didn’t just adapt to the planet—they learned to reshape it. From early fire use to today’s global supply chains, our cultural and social innovations have unlocked extraordinary power to transform Earth and improve human life. ...
Scientists have developed a fuel cell that uses microbes in soil to produce electricity. The device can power underground sensors for tasks like monitoring moisture or detecting touch, without needing batteries or solar panels. It works in both dry ...
That “magic” sponge under your sink may be hiding an environmental downside. While melamine sponges are famous for effortlessly scrubbing away stubborn stains, they slowly break down as you use them—shedding tiny plastic fibers that wash into ...
Scientists drilling deep beneath Greenland’s ice have uncovered a startling clue about its past—and future. Evidence shows that the Prudhoe Dome, a major high point of the ice sheet, completely melted around 7,000 years ago during a relatively ...
Long before rising seas swallowed Doggerland beneath the North Sea, this lost landscape may have been a surprisingly lush and life-friendly haven. New DNA evidence reveals that forests of oak, elm, and hazel were already thriving there more than ...
A hidden threat is emerging in the world’s glaciers: while most are shrinking, a rare group known as “surging glaciers” can suddenly accelerate, unleashing powerful and sometimes destructive ...
The ozone layer has been on track to recover thanks to the Montreal Protocol—but a loophole may be holding it back. Chemicals still permitted for industrial use are leaking into the atmosphere at higher rates than expected. Scientists now estimate ...
Researchers have discovered lithium hidden in pyrite within ancient shale rocks—an unexpected find that could reshape how we source this critical battery material. It raises the possibility of extracting lithium from existing waste, reducing the ...
Scientists have discovered that methane in the open ocean is produced by microbes under nutrient-poor conditions, solving a long-standing mystery. As warming oceans reduce nutrient mixing, these ...
For years, water managers have been puzzled as the Colorado River kept delivering less water than expected—even when snowpack levels looked promising. New research reveals the missing piece: spring rain, or rather, the lack of it. Warmer, drier ...
Africa’s forests have undergone a shocking reversal, switching from carbon absorbers to carbon emitters after 2010. Researchers found that heavy deforestation in tropical regions has led to massive biomass losses, far outweighing any gains from ...
Gray whales are beginning to break their long-established migration patterns, venturing into risky new territory like San Francisco Bay as climate change disrupts their Arctic food supply. But this unexpected detour is proving deadly: nearly one in ...

Latest Headlines

updated 12:56 pm ET