Long Arctic Indian Summer

For the moment, I want my readers to totally put all you have been brought to believe about the human impact on global warming completely out of your mind and travel with me on a thought experiment. Let us imagine that humanity is missing. What does the data tell us then?

500 years ago, we had a climate down shift called the Little Ice Age that ended the long lasting Medieval Warm P9eriod that had held sway for over two hundred years. Since then, the climate of the Northern Hemisphere has very slowly warmed back to the previous climate regime. My analysis of the impact of a modest positive warming influence has shown us that this can explain all the current evidence, and that we are about to have a full return to a warmer Northern climate.

The planet Earth has two natural heat sinks at the poles that operate over a yearly cycle due to the tilt of the poles. We like to ignore the Antarctic, but it is the dominant cooling engine, simply because it has a small continent able to collect an ice cap and a huge uninterrupted circumpolar ocean current that shields it from warm water intrusions. This is one mean cooling machine.

The arctic is the complete reverse of this. We have a land ringed deep ocean for most of the ice cap forming 15 degree polar area. There is only one break in this ring and it is fed by a large bounded north equatorial ocean that must pump warm water into the Arctic. Had this been engineered deliberately, I fail to see how it could have been improved on. We may discover, once all the crustal positions are properly worked out, that this is a rarity in global history.

Remember that the ocean rose 300 feet around 12,000 years ago. Prior to that the continental shelf was shaped by ocean currents and land erosion for millions of years. This unusually stable process formed long broad and very shallow coastal plains. This could never have happened if the sea level was shifting radically back and forth.

The indications are though, that left to its own devices, that natural climate balance for the Arctic is a little warmer than what we are experiencing now. The medieval Warm Period lasted a comfortable 200 years if not a great deal longer. The Bronze Age optimum lasted for thousands of years. In between, it is fair to say that it was more often warm than cold.

In fairness, all our information is drawn from proxies that are very prone to local variation. This is particularly a factor with shifting human settlement and disturbance. The only trustworthy information comes from pollen data from the more northerly transition zones and even that will actually lag the changes by a couple of centuries. We are experiencing that today.

The fact remains that a four hundred year climate cycle may simply defy resolution. The only certainty is that the antiquity of human habitation is universal.

The question then, is not why is it not warmer, but what causes it to chill out in the first place. Left to itself, the Arctic climate will moderate with total sea ice destruction every year. A moderate Arctic will mean less extreme winters throughout the Northern Hemisphere and improved growing conditions everywhere.

The good news, is that once the North is at its natural stability point around the complete elimination of summer sea ice, it appears to stay warm for a long time. There is likely enough freezing going on to prevent any cumulative heat retention.

The bad news is that sooner or later, the party is over.

My best theory, is that a surplus of Antarctic cold water is forced into the Benguela Current, strengthening it substantially and for decades lowering the temperature of the Gulf stream sufficient to allow ice accumulation in the Arctic. We are talking of a very small switch in energy transport when compared to the total regime. We do not even know if the atmosphere is a significant factor at this point.

All we really have is plenty of misunderstood and conflicting data of which we need a lot more.

When we see the world from this perspective, the good news is that it is getting warmer. The bad news is that this will end. And what did humanity have to do with any of this?

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