El Niño, a natural Pacific weather pattern that increases global temperatures, has officially begun, US scientists say.
The US National Oceanic and Atmospheric Administration (NOAA) has announced that El Niño conditions have begun in the tropical Pacific Ocean, amid a significant rise in sea surface temperatures in recent months.
Many forecasts indicate that this El Niño could be a so-called "super" El Niño, one of the strongest ever recorded.
With decades of human-induced global warming, 2027 is likely to be another record-breaking warm year, disrupting weather patterns, food supplies and economies throughout the year.
The announcement from NOAA (National Oceanic and Atmospheric Administration) is not unexpected. Forecasters had already predicted this warm phase after the end of La Nina, or the cool "brother" weather pattern earlier this year.
Sea surface temperatures in the central and tropical Pacific are now 0.5 degrees Celsius above the normal threshold that American scientists use to define an El Niño event.
"As El Niño conditions gradually developed over the past month, sea surface temperatures have risen above normal across the central and eastern equatorial Pacific," the agency said.
NOAA's weather agency has also observed changes in winds over the equatorial Pacific. This is a sign that not only is the ocean warming on its own, but that the atmosphere is now responding to the warming ocean.