‘In the long term, there is robust evidence of unabated global warming ..’
FRISCO — A shift in a decadal-scale cycle of Pacific Ocean temperatures could lead to a spike in global warming the next few years, climate researchers said after tracking a subsurface layer of unusually warm water in the Pacific and Indian oceans.
The layer, between 300 and 1,000 feet below the surface, has been accumulating more heat than previously recognized, according to climate researchers from UCLA and NASA’s Jet Propulsion Laboratory, who published their finding in the journal Science.
“Given the fact the Pacific Decadal Oscillation seems to be shifting to a warm phase, ocean heating in the Pacific will definitely drive a major surge in global surface warming,” said Veronica Nieves, lead author of the study and a UCLA researcher with the UCLA Joint Institute for Regional Earth System Science and Engineering.
The study used direct ocean temperature measurements, including observations from a global network of about 3,500 ocean temperature probes known as the Argo array. These measurements show temperatures below the surface of the Pacific Ocean have been increasing and that some of that water has been pushed to the Indian Ocean. Since 2003, unusually strong trade winds and other climatic features have been piling up warm water in the upper 1,000 feet of the western Pacific, pinning it against Asia and Australia.
“The western Pacific got so warm that some of the warm water is leaking into the Indian Ocean through the Indonesian archipelago, Nieves said.
The westward movement of the warm Pacific water pulled heat away from the surface waters of the central and eastern Pacific, which resulted in unusually cool surface temperatures during the last decade.
The shifts tracked by the study are related to a 10- to 30-year climatic pattern called the Pacific Decadal Oscillation, which has been in a cool phase for the past few decades. There currently are signs the pattern may be changing, with observations showing warmer-than-usual water in the eastern Pacific.