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RECookPE1978 Comment

Quote:“Can the Arctic really become sea ice-free during summer?
It has been suggested that the Arctic really can’t lose all its sea ice during summer because there isn’t enough energy to melt all of the ice in the short summer. There are a couple of reasons why this thinking is faulty.

The entire question is nonsense when at realistically.

The arctic sea ice reaches a maximum in late March – NOT the middle of winter up north! – when the arctic sun is present about half the time, and when it is dark about half the time. Thus, when it is -25- to -28 degrees C out there and completely dark for 24 hours of every day, the sea ice is still freezing up, gaining area and mass.
April-May-June-July, the arctic sun IS out, and the sunlight DOES reflect from the arctic sea surface and from the sea ice present up there. This is, obviously, “summer” … But the arctic sea ice is merely reducing from its March-April maximum of 14.0 Mkn^2. It is NOT anywhere close to “zero”, nor any fraction of “zero sea ice.”

Now, by August 12, the arctic sea ice melt ponds are receiving so little sunlight and so little heat that they begin re-freezing over each night. The total solar energy into the melt pond water (into the Arctic Ocean if the sea ice is melting at all) over an entire 24 hour day of 24 hours of sun is so little that the ice begins re-freezing on August 12.

Obviously, you are SUPPOSED to amuse that the “complete loss of sea ice” means that the arctic sea ice vanished in March and stayed away all “summer” only to begin refreezing during the darkness of “winter between September and March.

Now, there is STILL a large amount of sea ice loss between August 12 and the sea ice minimum in middle September. But does it matter – as Anthony asked the same question so effectively last September?

Let’s assume that a “complete loss of sea ice” does occur at some September minimum. Well, the difference in area between September’s AVERAGE sea ice minimum of 3.0 Mkm^2 and 0.0 Mkm^2 is .. well, 3.0 Mkm^2. So we lost “one Greenland”s ” worth of sea ice. Not the entire Arctic Ocean’s worth of sea ice by any means.

Further, we lost that sea ice between its “normal” sea ice edge latitude of 80 degrees north! There’s not much sun at 80 degrees north in September 1- September 30. And every day after 12 August, every hour after 1 September there is even less sunlight every day.

And, every hour of every day after 1 September, there is even less sunlight, striking at an even lower angle above the horizon, and striking through an ever-longer, ever-thicker atmospheric attenuation blanket.

So, even IF the entire arctic ocean were “ice free” on September 15, it would be receiving very little solar energy, the melt ponds would have been refreezing for 4-6 weeks already, the snow on top of the sea ice would be building up, and the sun would be underground for more and more hours every day after the sea ice minimum was reached.

So what? if all of the arctic sea ice melted one September, the Arctic ocean would lose more heat energy from the exposed ocean water than it would gain from the sunlight into that exposed ocean water.
Now, if “all of the arctic sea ice were lost earlier” – say by 1 August somehow, when the sun is higher in the sky for more hours of the day than it is in mid-September?

If so, the question becomes: What happens next?

Well, by 1 September, the increased losses from increased evaporation, convection, conduction and LW radiation losses STILL mean 1 September will mark a time when heat losses exceed heat gains from solar radiation into the newly exposed ocean water. The sea ice melt ponds will continue refreezing each night – just like they did on 12 August when Judith Curry was observing them at 79 north. And so, the minimum sea ice point comes a little bit earlier that year (due to the increased losses of ocean surface heat) and the sea ice looks the same in October as it did the previous October.

So, more sea ice loss between 1 September and 30 March = more heat loss to space through evaporation, convection, and conduction and radiation!

So, even IF the entire arctic sea ice vanishes in September one year, there is no effect the following months, years, or decades on the arctic.

Over the winter, regardless of how much sea ice is present in September, the arctic ocean will refreeze. A claim that the next five years of multi-year ice is “gone” can be made, but there is no evidence that that event has any effect. Most multi-year ice vanished in 2007, and the sea ice recovered.
Most of the multi-year ice melted in 2012, and the sea ice recovered. In fact it increased in area – and area is the thing that counts in reflecting solar energy from the sea ice or from the ocean water.
It is our attitude toward free thought and free expression that will determine our fate. There must be no limit on the range of temperate discussion, no limits on thought. No subject must be taboo. No censor must preside at our assemblies.

–William O. Douglas, U.S. Supreme Court Justice, 1952

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