http://neven1.typepad.com/.a/6a0133f03a1e37970b022ad3886ed2200d-800wi

Another way of looking at how the Arctic ice is vanishing before our eyes. The black dots tell us when the Arctic sea ice extent was lowest for each labeled year, and what its value was when in bottomed out. The red dots tell us how the current year (2018) is working out.

Note the position of the 2012 dot, the low ice record year, due to a perfect storm of clear skies, high temperatures, low precipitation and destructive current and wave action, Still, one year, in isolation, tells us little, there will always be outliers in any data set. Note, instead, the trends. Almost all of the 21st century minima are clustered at the bottom of the graph, below the 6 million km^2 mark. Almost all of the lows for the preceding decade are at the top, above the line.

It seems unlikely 2018 will beat the 2012 record, but it is already (in mid August) lower than any of the mid-September minima for the entire 20th century.

I’m sure AGW skeptics will point out that variability in Arctic ice cover is to be expected, at any time resolution you choose to sample at. But just this quick look at the last three decades should be enough to make us suspect that such a clear trend in such a short time (by geological standards) is simply not natural.

I suppose it is possible the extreme weather events the world has experienced this year may not be due to this gradual warming of the Earth’s atmosphere and oceans. But the burden of proof must lie on the denialist camp.

Incidentally, I must once again point out that Arctic Sea Ice extent is only one of many parameters and metrics that can be used to measure the effects of climate change. I choose to concentrate on it because it is unambiguous, continuous, it is the result of one number provided by one sensor, and because we know the Arctic basin is particularly sensitive to global warming and the positive feedback mechanisms there are most pronounced. The canary in the coal mine is suffocating before our eyes.