A few days ago, according to foreign media reports, a new study by the National Center for Atmospheric Research (NCAR) of the United States shows that the Arctic is beginning to transition to a new climate state. The Arctic has been cold for thousands of years, and there will be natural fluctuations within a certain range. But now, scientists have found that these fluctuations are moving away from expectations and heading for a “new Arctic” climate. “It’s a period of such rapid change, and the rate of change is so significant that the Arctic has entered a completely different climate than it was a few decades ago,” said Laura Landrum, lead author of the study With sea ice levels at record lows and temperatures at all-time highs in recent years, the team hopes to investigate whether the Arctic climate is fundamentally different from what it was a few decades ago. For this reason, they used a large number of observational data of Arctic climate conditions to delimit the boundary of the “old Arctic” in statistics, and used hundreds of computer simulations to predict the conditions forward. < p > < p > among them, the three main factors considered by the research team are sea ice extent at the end of summer (at the lowest point of each year), temperature in autumn and winter, and precipitation days. To this end, the team applied statistical techniques to define when the usual change in each of the three numbers exceeded the natural change. Basically, if the 10-year average of a number is more than two standard deviations from the average of the 1950s, a new climate is formed. < / P > < p > through the team’s reasoning, they found that a new climate had emerged at the beginning of the century for the extent of sea ice. The average minimum temperature in September is now 31% lower than in the decade from 1979 to 1988. If greenhouse gas emissions are still high, the team predicts that by the end of the century, the Arctic could be almost ice free for three to 10 months a year. The air temperature over the ocean will enter a new climate by 2050, and the air temperature over land will follow up in the second half of this century. For changes in precipitation, the team found that by the middle of the century, the rainy season could extend by 20 to 60 days, and by 2100, it would have extended to 90 days. < / P > < p > Laura Landrum points out that “the Arctic is likely to experience extreme conditions of sea ice, temperature and precipitation that go far beyond anything we have experienced before. Then we need to change the definition of Arctic climate. ” Didi Qingju bicycle has entered 150 cities