There is less and less ice in the Arctic. 2017 did indeed set yet another record in the negative: last March, when the extent of winter ice should be at its maximum, an all-time low was reached instead, never observed since measurements began (1979). If in 1985 ice more than four years old accounted for 16 per cent of the pack, by March 2017 it was just 0.9 per cent. Today 79 per cent of the ice is the youngest kind — that is, ice that forms within a single season.

What does all this mean? It means that in 30 years we have lost an area almost four times the size of Italy. The ice extent in March was 8 per cent below the 1981–2010 average, standing at 14.42 million square kilometres.

The data come from the latest Arctic report card, an annual publication produced by Noaa, the United States agency for the oceans and the atmosphere, which brings together the work and scientific publications of 85 researchers from twelve different countries. "The Arctic shows no signs of returning to the reliably frozen region it was decades ago," Noaa writes in a press release. "Temperatures in this region continue to rise at twice the rate of the increase in global temperature."

The Arctic is warmer, greener, with less and less ice

A "new normal", is how researchers describe it. Indeed, according to palaeoclimatic studies (Kinnard et al., 2011), the current rate of sea ice decline and temperature increase observed are higher than at any other point in the past 1,500 years. And this goes hand in hand with the rise in the concentration of CO2 (carbon dioxide) in the atmosphere and a consequent increase in average global temperatures. Increases that coincide with the onset of the first industrial revolution.

UN Climate Change @UNFCCC

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Did you know: According to the the US National Oceanic and Atmospheric Administration, 75 to 80% of the Arctic's permanent ice has melted in the last 35 years, mainly as a result of burning #fossilfuels and #deforestation @NOAA #climatechange

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2017 was also the second year in which an air temperature value above the average was recorded: +1.6 degrees compared with the period from 1981 to 2010. Surface waters are warmer too: in the Barents Sea and the Chukchi Sea, temperatures in August 2017 were as much as 4 degrees above the average.

The boomerang effect of Arctic ice melt

Reduced snow cover triggers a feedback process that contributes to driving temperatures up more sharply. This is because ice allows part of the sun's rays to be reflected, thereby reducing the amount of energy reaching the Earth's surface. More sun and more heat therefore means growth in phytoplankton and marine plants in the Arctic seas, a trend also recorded in the tundra, with the progressive thawing of permafrost. Larger trees and shrubs, which are moving into what were once pastures and tundra.

2017 the second warmest year since temperatures have been measured

The substantial report pairs with the latest findings released by Nasa and Noaa: even without the effect of El Niño, 2017 was the second warmest year ever recorded. "The planet's overall temperatures continue the rapid warming trend we have seen over the last 40 years," said Gavin Schmidt, director of Giss (Goddard institute for space studies). "The average surface temperature of the planet has risen by just over 1° Celsius over the last century, a change driven largely by the increase in carbon dioxide and other emissions released into the atmosphere by humans."