NEW YORK, April 20: A Japanese laboratory has built the world’s fastest computer, outdating IBM’s supercomputer which led the industry until now.

The Japanese machine is so powerful that it matches the raw processing power of the 20 fastest American computers combined and far outstrips the previous leader IBM.

In a report the New York Times said that the achievement, which was reported on Friday by an American scientist who tracks the performance of the world’s most powerful computers, is evidence that a technology race that most American engineers thought they were winning handily is far from over. American companies have built the fastest computers for most of the last decade.

“The accomplishment is also a vivid statement of contrasting scientific and technology priorities in the United States and Japan. The Japanese machine was built to analyze climate change, including global warming, as well as weather and earthquake patterns. By contrast, the United States has predominantly focused its efforts on building powerful computers for simulating weapons, while its efforts have lagged in scientific areas like climate modelling,” the paper said.

For some American computer scientists, the arrival of the Japanese supercomputer evokes the type of alarm raised by the Soviet Union’s Sputnik satellite in 1957.

“In some sense we have a Computenik on our hands,” said Jack Dongarra, a University of Tennessee computer scientist, who reported the achievement. For many years he has maintained an authoritative list of the world’s 500 fastest computers.

Several United States computer scientists said the Japanese machine reflected differences in style and commitment that suggest that United States research and spending efforts have grown complacent in recent years.

For now, the new computer will be used only for climate research, and American scientists have already begun preparing to move some of their climate simulation research to run on the Japanese machine.

“The Japanese clearly have a level of will that we haven’t achieved,” Thomas Sterling, a supercomputer designer at the California Institute of Technology told the Times. “These guys are blowing us out of the water, and we need to sit up and take notice.”

The new Japanese supercomputer will have both scientific and practical applications. It will be used for advanced modelling of theories about global warming and climate change, and it will be able to predict short-term weather patterns.