"Mark Serreze, director of the U.S. National Snow and Ice Data Center, also welcomes the new analysis but points out that Arctic amplification is never a fixed

"Mark Serreze, director of the U.S. National Snow and Ice Data Center, also welcomes the new analysis but points out that Arctic amplification is never a fixed ratio. As the researchers showed, the time span used to calculate the rate matters, as does the latitude and season—amplification is far larger in the winter. Serreze adds that Arctic warming has always been more uncertain than the rest of the world, because of the spottiness of the observational records. “As a result, I’m always in favor of looking at it as a range,” he says. “Two times to four times.”"