Arctic Melting Is Good

Sea Ice Extent

Sea Ice Extent

Arctic Melting Is Good. You do not want those summer low ice extents getting higher (showing more retained ice each summer, year over year)

You Want Arctic Ice Cap Melting

Why you want it is a bit harder to explain. The simplest form is that as long as the Arctic melts, we do not have the Next Ice Age Glacial. The mechanism took a very long time to work out.

The story of that “working out” is in a fascinating little book that is very easy to read. The title is “Ice Age” with the subtitle “The Theory That Came In From The Cold”. Written by John and Mary Gribbin. A slim book of 105 pages, it is a very easy and very pleasant read. The bulk of the story is given over to the character and history of the folks who worked out the existence and mechanism of the Ice Ages. Along the way you learn, rather painlessly, how the Ice Age Glacial cycle works.

Before getting too far into it, a word or two on terminology. “Ice Age” is ambiguous. It can mean either of two very different things. One is an “Ice Epoch”. Long periods of ice that happen every few millions of years. These look to be driven by our position relative to the galactic arms. We are presently in just such an Ice Epoch. Within these Ice Epochs, we have periods of heavy icing of the Earth. These are properly called “glacials”. They are periodically interrupted by “interglacials” when the ice melts. We are presently living in just one such interglacial. One Glacial / Interglacial cycle runs about 120,000 years with the interglacial typically being about 12,000 years, give or take a few thousand.

We are presently nearing the end of our warm interglacial. It started about 18,000 years ago, had a brief setback, then warmed to a maximum about 6000 years ago. We’ve been getting colder ever since. Because of that potential for confusion, I will typically use “Ice Age Glacial” for the times of ice and “interglacial” for times without the ice. Rarely do we really mean the last “Ice Epoch” when we say “the last Ice Age”. What we really mean is “the last glaciation of this Ice Epoch”. So I try to avoid using the term “Ice Age” unadorned by something that tells you if it means “Ice Epoch” or “glaciation”.

What causes an Interglacial?

The key to it all is melting of the Arctic Ice Cap in the summer. When that happens, we get an “Interglacial”. A time like now when the world is a relatively warm and pleasant place to live. When that does not happen, we have a “Glacial” episode and ice covers Canada, Sweden, Scotland, Russia and many other places to great depth. The rest of us are not covered in ice, we’re simply frozen and starving.

The Earth has three motions that matter most in this. The Earth tilts on its axis, it leans over about 23 degrees. But this is not a constant. It slowly changes and bobs up and down. Sometimes the top of the Earth points more directly at the Sun. Sometimes it points more directly straight “up”.

The orbit of the Earth can get more round, or more elliptical. This can put the pole closer to the sun, or further away. Not much, just a little. The degree of ’roundness’ changes over time.

The direction our “tilt” points drifts relative to our position in the orbit. Sometimes the “tilt” causes the North Pole to point at the sun when the Earth is closest to the Sun. Sometimes it makes this happen when the Earth is furthest away from the Sun.

For the Ice Age Glacial to end, the northern polar ice sheet has to be warmed just enough more to melt. This only happens when all three of those cycles “sync up” with the happy circumstance that the North Pole points most fully at the Sun, and is well ‘tipped over’ to get a good warming, right as the Earth is closest to the Sun in summer. In June, we want the North Pole tilted fully over and basking in the Sun at closest approach in our orbit.

If we don’t get that, we get an Ice Age Glacial.

What is the first sign of the return of the Ice Age Glacial? The North Pole Ice Cap does not melt in summer, but carries over, from year to year, so that ice can build up. Starting the process of building up an Ice Age Glacial ice sheet. That, we don’t want. So we want that ice to melt each summer.

Ice Age – The Book

Here are some selected passages from the book, with some of my comments about the biggest ‘take away’ for me. I’ve added the bolding.

Page 56:

As we mentioned earlier, given the present day geography of our planet – the distribution of the continents and oceans – the natural state of the Earth is in a full Ice Age. Koppen was correct in highlighting the importance of summer warmth in influencing the advance and retreat of the ice in the Northern Hemisphere. But in a sense, he too, got the argument backwards. It isn’t so much that Ice Ages occur when the environmental influences conspire to produce particularly cool summers; rather what matters is that Interglacials only occur when the astronomical influences conspire to produce unusually warm summers, encouraging the ice to retreat.

There is then a very interesting discussion of the history of the development of ocean bottom core samples and analysis, including an overview of how microscopic sea shells are used along with other things. Then the discussion turns to oxygen isotopes, and some of the early results showing one degree of change, with later results being clarified by a different technique. Of particular interest to me was how little cooling is needed to the downside to put us into an Ice Age Glacial event.

Page 71:

The multi-factor technique showed that changes in salinity of the surface waters of the Caribbean had, indeed, played an important part in influencing the foram populations; but it also showed that the temperature fluctuations in the region associated with Ice Ages corresponded to a drop of only 2 degrees C, whereas Emiliani’s analysis had indicated a drop of 6 degrees C. Something else was amplifying the isotope changes when the Earth cooled.

The obvious candidate for that something else was the way water gets locked up in great ice sheets during an Ice Age. When water evaporates it is easier for the lighter molecules to escape into the air, so the water left behind tends to have a higher proportion of oxygen-18; much of the evaporated water, relatively rich in oxygen-16 compared to the water left behind ( exactly how rich also depends on the temperature), falls as snow during an Ice Age, and gets locked up as ice instead of being recycled back into the sea.

Just 2 C and we’re hard core into an Ice Age. To the extent there is a tipping point, it is to the downside. Into an Ice Age Glaciation.

This insight also lets you use the oxygen ratios to tell just how big the ice sheets were, as the ratio changes in sync with the mass of snow and ice trapped on land.

They then note that ‘raised beaches’ were noticed by Charles Darwin on his expedition aboard HMS Beagle. “Darwin, who was a geologist before he made a name as a naturalist, was one of several such pioneers who noticed raised beaches, several metres above the present day sea level, in different parts of the world”

Very early on folks were noticing that water has been deeper in the past, and that implies that the Earth has been warmer in the past, all without our help.

Page 74-75:

By the middle of the 1960s, Wallace Broecker and his team at Columbia had used the thorium technique to show that raised beaches in islands of both the Pacific and the Atlantic oceans corresponded to a period 120,000 years ago when the sea level was six metres higher than it is today; slightly less compelling evidence indicated another, but less extreme, increase in sea level about 80,000 years ago.
[…]
This work encouraged other researchers to investigate the raised features carved by ancient waves at sites around the world, and by 1968 it was clearly established that sea level had been high around the world 125,000 years ago, 105,000 years ago, and 82,000 years ago, as well as today. These dates correspond to warm periods predicted by the Milankovitch Model, provided that all three of the astronomical effects, and the way they interact with one another, are allowed for.

Clearly the Earth goes through very natural cycles of warming and cooling all the time, and by amounts far greater than anything seen in the last couple of thousand years.

Let me quote from pages 88-89:

The escape from Ice Age conditions, beginning 18,000 years ago, required the combined influences of all three astronomical cycles to drag the Earth into a peak of warmth about 6,000 years ago. Orbital eccentricity changes combined with a shift in the wobble of the Earth which made June the month of closest approach to the Sun, boosting the heat of Northern Hemisphere summers, just at a time when the tilt of our planet reached a maximum, putting that summer Sun particularly high in the sky. Since 6,000 years ago, all these factors have turned around, and conditions for Northern Hemisphere summer warmth are becoming less favourable. The prospect is for a return of Northern Hemisphere glaciation, on a timescale of thousands of years.

There are other lines of evidence that support the notion that the world was warmer 6000 years ago than it is today. Even just a couple of thousand years ago, sea level was higher than now. We are already 6,000 years into the start of The Next Ice Age Glacial. It is simply arriving so slowly that we don’t notice much.

http://wattsupwiththat.com/2008/10/21/researchers-find-arctic-may-have-had-less-ice-6-7000-years-ago/

https://chiefio.wordpress.com/2010/12/06/ostia-antica-and-sea-level/

And just a bit further down on page 89:

It seems likely that the reason for this is that the overall climate is driven by what happens in the Northern Hemisphere ( which is particularly sensitive to the astronomical influences, for reasons we already explained), with the addition of feedbacks, such as changes in the ocean currents of the kind discussed originally by Croll. Another way of looking at this is to start from the fact that the conditions which are required to melt snow and ice on land in the Northern Hemisphere ( warm summers, causing an interglacial ) go hand in hand with relatively warm winters in the Southern Hemisphere, and this discourages the formation of extensive sea ice. The land of Antarctica is always covered by ice, even during an Interglacial, and particularly cold winters are what you need to freeze the top layer of the oceans.

So here we also find that those ice shelves in the Southern Ocean calving from Antarctica are not something to fear, but something to cheer. It is only when the sea ice in Antarctica is failing in slightly warm winters and the Arctic Ice Cap is melting in warm summers that we have our present warm planet.

The things that are most desired by the Warmistas, growing winter ice shelves in Antarctica and stable multiyear ice in the Arctic Ice Cap are “exactly wrong”. They are the harbingers of doom in an icy grave, the signs of the Next Ice Age Glaciation underway.

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About E.M.Smith

A technical managerial sort interested in things from Stonehenge to computer science. My present "hot buttons' are the mythology of Climate Change and ancient metrology; but things change...
This entry was posted in AGW Climate Perspective, AGW Science and Background and tagged , , , . Bookmark the permalink.

18 Responses to Arctic Melting Is Good

  1. Luke Warmer says:

    Interesting stuff. The Eemian is a strange one and we have much to learn from understanding it so it was good that Nature recently announced that more research was taking place on this time “when the average global temperature was about 5°C warmer than today”

    http://www.nature.com/news/2010/101231/full/469012a.html

    However, the Wikipedia page for the Eemian (bearing many illogical edits from William Connolley aka the stoat) states that “The prevailing Eemian climate is believed to have been similar to that of the Holocene”. This statement despite the many 5 metre+ wave cuts around the world.

    Other crass statements from the Wiki page include “although global annual mean temperatures were probably similar to those of the Holocene.” whatever that means given the fluctuations during the H, and “the northern hemisphere winters were generally warmer and wetter than now, though some areas were actually slightly cooler than today”.

  2. Pascvaks says:

    O/T – Probably more my old computer and snailspeed dialup. Usually open at “About” since “Home” is often such a BIG page. Often, not always, when I hit a link to one of the articles from “About” it will open as a secure page –ie:”https”://chiefio.wordpress.com/2011/01/05/forcing-is-a-broken-word/#comment-11000. When this happens, as it did this am, and I try go on to another article (especially if I open the new article as a new page) the page tend to open as “http” and not “https” and I get a little window that says an error has occured and shuts the new page down. If any of this gives up anything useful that was what I was trying to do. One day I’ll fix my son’s old (newer) compter and get a coax hookup with more speed. FWIW;-)

  3. Pascvaks says:

    (SarcOn) My grandmother, Nana, my dad’s mom, appeared to me in a dream not too long ago. She said that the bestest, most award winning TV show in heaven for the last 4 million years was a comedy called “Life On Earth”. Until now I wasn’t sure if I had heard her right. Hummmm… you know, I’ll bet they’ve been laughing their wings off for the last 40 years.(SarcOff)

  4. GregO says:

    Chiefio,

    Yes we certainly want the arctic ice to melt every summer and that is a good thing to keep in mind as we cheer the ice on every year in support of this or that climate theory.

    Once the ice encroaches from the poles upon the earth, humanity will suffer and even possibly be exterminated if we get back to a snowball earth.

    Global warming – another term for nice weather!

  5. Pingback: Global Warming Hoax Weekly Round-Up, Jan 6th 2011 « The Daily Bayonet

  6. PhilJourdan says:

    The things that are most desired by the Warmistas, growing winter ice shelves in Antarctica and stable multiyear ice in the Arctic Ice Cap are “exactly wrong”.

    Not really. If you realize their goal is total control over everyone’s life, how better to achieve that than to create a state of eternal dependence?

  7. George says:

    I read a paper last year in Quaternary Research where sea levels has been 2 to 3 meters higher than today only 6000 years ago. This was measured by looking at “flat top” atolls in the Pacific in an area where the crust is extremely stable.

    Imagine you have a coral atoll and the water just barely covers the surface. The corals will grow according to their optimum depth. Now imagine the sea level falls and exposes a portion of it. The corals at the top which become exposed will die but the area under water will continue to grow producing a “shoulder” formation on the atoll. As sea level rises and falls, you get a series of these that represent the top of the coral growth. These can be dated. Several of these atolls were visited and core samples were taken.

    This research was backed up by another paper that showed sea levels were also higher in what is now Western Europe.

  8. ArndB says:

    One can talk so nicely on what happened many thousand years ago, and indeed it is often fun (as long as one believes that warming is the future to come), but is quite reluctant to require from science a thorough explanation of the first biggest climatic shift after the LIA that occurred in the Arctic 90 years ago and produced a NH warming from 1919 to 1940.
    See here
    __Nov2009: http://wattsupwiththat.com/2009/11/04/arctic-warming-goes-with-the-floe/
    (with figures in PDF: http://www.arctic-warming.com/_FIN_Feb2010_WEB_CC_Arctic1919.pdf ),
    ___Nov2010: http://diggingintheclay.wordpress.com/2010/11/20/did-the-previous-arctic-warming-start-in-1910-or-in-1919/
    ___and a book, 116 pages 2009 here: http://www.arctic-heats-up.com/

    The amount of data and information collected and published 90 years ago had been not so few that a more thorough analysis could have benefited the recent discussion significantly.
    Regards Arnd Bernaerts

  9. pyromancer76 says:

    E.M., I hope there are enough copies for people to buy. I got mine from your last recommendation and I imagine many more will after this post. Always enjoy the history of an awareness, an idea, a theory, and then the search for proof — and finally what is done with the “knowledge”. Have only begun due to remodel, grandchildren (one pure joy in life even with a five-month old screaming for 1-1/2 hours last night about mommy [mostly] and daddy being gone), and just life.

    Hope some of the information will connect with William McClenny’s piece (WUWT 12/230) “The Antithesis”. Again, I have only begun both, but this seems like some of the most important data that we need to, must, get somewhat straight. Our progeny depend on our success, and our ability to isolate and eliminate as much fraudulent science as possible. ‘Tis probably arrogant, but I think we can “do something”, don’t know what, about keeping the ice at bay if we catch it early enough. The cold we probably have to bear and all the issues with agriculture, mining, manufacturing, and transportation. But, but, we are not helpless with today’s technology – I think, and I hope.

  10. P.G. Sharrow says:

    Be careful about what you wish for.

    An open arctic ocean could lead to the following scenario.

    Heavier “lake effect” snows on the land around the arctic ocean causes change in albedo and decreases heating of the land and air over it. Lose of energy to the northern atmosphere by condensation and freezing warms the polar area, ( less intense cold) and cools the high latitude land areas. As the Arctic ocean evaporates it sucks in more “warm” water from the south that helps to keep it open as well as increased salinity that reduces freezing temperature of that oceans water. This results in more “lake effect” snow on the land and additional albedo changes as snow accumulates farther south. This will continue until the ocean level becomes too low to replace the evaporation from the arctic and it cools down and freezes over completely. Now the entire area turns into a cold desert as is the Antarctic. The Antarctic is surrounded by ocean and is relatively stable. The Arctic is surrounded by land and is unstable. South of the great northern ice sheet is cold and desert like with great dust storms. In time (a long time) the ice sheet is no longer white snow but dirt covered muskeg. The change in albedo causes the cold land and atmosphere to heat up. The warm storm track moves north and warm wet storms speed up the end of the “ice age” and refills the oceans. Interglacial until the Arctic melts and gets warn enough to start this over. All we need is a quiet sun for long enough time to get the second heavy snow winter on top of the first. pg

  11. Duster says:

    A possibly more common pair of terms for the long term climate shifts are “Icehouse” and “Green- or Hot House” earths. With the exception of the Ice House stage during the Mesozoic (see Shaviv and Veizer 2003 GSA TODAY, Figure 1), Icehouse phases are the only geologic periods when there is evidence of polar ice caps. The episode during the Mesozoic differs because while there is evidence of some continental-located glaciers, no indications of a polar ice cap have been recognized.

  12. E.M.Smith says:

    @Pascvaks:

    I’ve shortened the default articles displayed list to 4 from 8 so hitting the main page will have less ‘weight’.

    I can not explain the https behaviour. The only https setting I have is to use it for administration pages (i.e. me, doing site management). I only turned that on a couple of weeks ago so if your issue showed up then, let me know, it could be a bug… if your issues has been around longer, then that’s not it.

    @Pyromancer76: I expect they will print more as needed ;-)

  13. kuhnkat says:

    I, like many people, have been fascinated by the Mammoth hunter human picture. Of course, when frozen mammoths were found with temperate foliage in their bellies it kind of changed that solid picture of the ice hunter we had been sold.

    A recent study in South America of lake bottom sediments has now shown that it is likely that there was a full rain forest ecology right through the last glaciation. That, combined with the probable loss of many species which would not have quickly returned if the CO2 had actually gotten as low as implied by an AVERAGE 280ppm CO2, makes me doubt the overall idea of a snowball earth with life barely hanging on the edge of survivability.

    Arm waving warning!!

    My fantasy starts with the idea of the glaciation moving huge amounts of water onto the continents and lowering sea levels exposing the continental shelves and other shallow ocean areas. These lower areas will have higher atmospheric pressure and should be slighly warmer. I am wondering if the loss of large amounts of land not much used by humans would be replaced by small amounts of rich land for farming and quite habitable after a few years of drying out. We should also see the Sahara and the Australian Outback both return to useable form!!

    Take a look at this map:

    I know, sitting in Southern California it is easy for me to say!! I guess the real issue is whether the weather would be more violent with cold air being transferred to more temperate areas like we are seeing this winter!!

    Anyone know of research in that direction or am I totally delusional. I would also offer that we are finding more and more ancient buildings and stonework in those low lying areas from known and unknow civilizations.

    Warming the earth should be easier than trying to cool it. Sowing high albedo material over snowfields coupled with orbiting mirrors to add extra energy where needed would seem to handle the situation. Unlike power systems focusing the energy would not be necessary so shouldn’t be a particular danger. Still a rather stiff cost to deploy enough maneuverable reflectors and provide station keeping energy.

    Maybe ginormous reflectors at the leading and trailing lagrangian points to minimize maintenance?

  14. tckev says:

    Chiefio –

    Agreed! The arid dryness of glaciation is not wanted.
    Warmth and water is what keeps most of life going.
    Would certainly make the sea journeys from USA to Europe and beyond a more viable option if the warming era was to continue, allowing shipping to navigate a northern route.

    I also wonder how the ‘Warmistas’ and climate change dis-telligentsia are so sure about how our atmosphere works when a little thing like this are left unexplained –
    http://science.nasa.gov/science-news/science-at-nasa/2010/15jul_thermosphere/

  15. E.M.Smith says:

    @Kuhnkat:

    Strange you should mention old civilizations in the pre-interglacial era… I just put up a posting on that:

    https://chiefio.wordpress.com/2011/01/06/gobekli-tepe/

    And yes, I’d expect some really nice ‘coastal plains’ for living.

    @tckev:

    Thanks for that link! I’ve read indirect reports, and I think that is critical to understanding the ‘what happens next’ connections, but had not found the NASA article….

    The sun sniffles, the atmosphere catches cold, and we freeze or tookas off…

  16. Pascvaks says:

    Ref – E.M.Smith on 6 January 2011 at 2:57 pm
    @Pascvaks: “I’ve shortened…”

    Yes it does seem that it started only a couple weeks ago. Had been opening via ‘About’ for quite sometime before. Now using ‘”Rules”‘ as of this morning when I opened via ‘About’, deleted the ‘About’ cookie, and opened “Rules” and added it as the link on the directory.

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  18. NZ Willy says:

    Regret to inform you that currently the Earth is furthest from the Sun during northern hemisphere summer, on July 7 precisely. Earth is nearest on January 7. So your confluence of 3 important effects — ain’t.

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