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By Paul Homewood

https://www.theguardian.com/environment/2012/sep/17/arctic-collapse-sea-ice

For years we were assured that the summer sea ice in the Arctic would be long gone by now. After all, even that expert Al Gore pronounced in 2009 that it would have all melted away within four years, and many other Arctic experts concurred.

But when it comes to climate clowns, surely the gold medal must go to Peter Wadhams, who is amazingly still Professor of Ocean Physics, and Head of the Polar Ocean Physics Group at Cambridge University. His predictions included these beauties:

 In 2012, he predicted that the Arctic would be ice-free by 2015/16
• In 2014, he thought it might last till 2020.
• In 2016, he confidently predicted the Arctic would be ice -free that summer (though curiously he now defined ‘ice-free’ as less than 1 million square kilometers!)

In reality, the ice has robustly recovered from its low extent in 2012, and this year has seen the highest minimum extent since 2014, and the fourth highest since 2007:

https://nsidc.org/data/seaice_index/archives

Moreover there is plenty of thick ice left in the central Arctic, in stark contrast to September 2009:

http://ocean.dmi.dk/arctic/icethickness/thk.uk.php

The message from the data is by now abundantly clear – Arctic sea ice is going nowhere. Since 2007, sea ice extent has actually been remarkably stable. I am often criticised for cherry picking 2007 as the start point. There was certainly a declining trend prior to that year, which began in the 1980s, and it is often claimed that shorter term trends are meaningless.

However, a lot of thick, multi year ice was lost in 2007/8, much swept out into the Atlantic by ocean currents. Basic physics tells us that the thinner ice which replaced it melts more easily in summer. Indeed, it was this very factor which prompted the forecasts of Wadhams and co. Like it or not, current sea ice extents are still largely determined by the events of 2007/8.

In short sea ice extents are not going to simply return to pre-2007 levels just like that. Indeed, it will probably not start to happen until the return of the AMO cold phase, which saw rapid refreezing in the 1970s.

via NOT A LOT OF PEOPLE KNOW THAT

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September 21, 2021