Alarming data is coming from the Arctic Circle. Anomalous temperatures and sea ice extent at a minimum. The Cnr warns: “The ice that is lost cannot be recovered.”
There should be more ice, much more. And temperatures should be wintry, below zero. But that is not the case. According to researchers at both the Danish Meteorological Institute and Rutgers University, both engaged in monitoring temperatures and ice cover above the 80th parallel, temperatures in the Arctic are "only" 5 degrees below zero, when they should be at least -25°C.
In some areas of the Arctic Circle, air temperatures 20 degrees above average have been recorded, while sea water temperatures are 4 degrees above average. "In October and November there was a record decline in sea ice across the entire Arctic," explains Elisa Palazzi, a researcher at the Cnr's Institute of Atmospheric Sciences and Climate (Isac). "This is a problem because such a situation makes it difficult for new ice to form. Indeed, the ice that does form is getting thinner and thinner."
Scientists say they are "surprised" by these anomalies, which nonetheless appear to confirm the negative trends recorded in recent years. This is also borne out by data collected by the National Snow and Ice Data Center (NSIDC), which last October reported that at the end of September sea ice extent had hit yet another minimum, reaching 4.72 million square kilometres. A steady decline losing 13.3 per cent every decade. "The reduction in ice means there is greater solar exposure, and this triggers further warming of sea waters," Palazzi continues. "This is a well-known feedback mechanism and a self-reinforcing cycle. Less ice corresponds to greater warming. That is why the pole is one of the sentinels of climate change."
Nasa says the same, at the end of this year's winter season. Between February and April, the Arctic Ocean should reach its maximum extent. But on 24 March last year, ice extent stopped at 14.52 million square kilometres, representing "a winter minimum since 1979, that is, since satellite measurements began." Nasa explains that over the past 13 years, new lows in glacial extent have been recorded every year. "This is indeed an exceptional phenomenon, but one that fits into a trend that was to be expected. In the space of 25 years, sea ice has lost 30 per cent of its extent."
"A phenomenon that certainly raises concern," the Cnr researcher concludes. "Also because if we look at the most optimistic climate models, what we can expect for sea ice is a stabilisation relative to the signals seen so far. But the ice lost so far will certainly not be recovered." All the signs of distress from the northern part of the planet are there, and they appear to be growing ever more alarming.
