West Antarctica Melting, Amazon Not Helping

A curious fact has baffled those who observe Earth: the Antarctic sea ice has been augmenting, year after year (whereas it has been shrinking year after year around the North Pole, as expected). How could the former fact, increasing sea ice, be compatible with global warming?

Scientists have been baffled. Some meekly suggested that stronger winds spread the cold water, and sea ice, further out. Winds have increased in the Antarctic Ocean, indeed. The latter point is straight from what one would expect of global warming: heat is motion on the smallest scale, resulting in density differentials, thus pressure differentials, hence winds, from high to low pressures.

The continent of Antarctica seems to be a solid mass, but the reality below all that ice is different. If one melted all the ice, Antarctica, at this point is more like an archipelago.

All Antarctica That Is Blue Will Be Under Water Soon

All Antarctica That Is Blue Will Be Under Water Soon. So Will Be Most Coastal Areas Around the Continents.

(However, if the ice melted, the continent would raise by hundreds of meters… I would guess, taking into account that rock is about three times the density of ice. But that would take millennia. Many quakes, as still experienced in Scandinavia, which is still rising at the pace of one meter per century.)

Notice that it is often much deeper inland than along the continental margins. The West Antarctic Ice Shield (WAIS; drained by the Pine, and other glaciers mentioned below) is on the left. To the bottom of the page, one sees the Wilkes Subglacial Basin I mentioned in 2009. Right of it is the Totten catchment and Aurora Subglacial basin.

The Wilkes Subglacial Basin Was Part of the Ocean In the Pliocene, 5 Million Years Ago

The Wilkes Subglacial Basin Was Part of the Ocean In the Pliocene, 5 Million Years Ago

Most of these three giant basins have up to 4 kilometers of ice any of these If the three of them melted, sea level would go back to conditions 5 million years ago (when CO2 levels were the same as today). The ocean would be up to 40 meters higher.

I will suggest a much more sinister explanation for the spreading of the sea ice around Antarctica (sinister explanations are my specialty).

The dynamics of water in the ocean is dominated by its density, and friction of atmospheric winds on its surface (the latter creating trade winds and storms heading east below the two main temperate jet streams centered around 45 degrees, plus upwelling; all of this consequences of Earth’s mighty rotation and the Coriolis force).

Denser water sinks, less dense water rises. Water density itself is a two-dimensional quantity: it depends upon temperature, and salinity. The more salt, the more dense, the more the water sinks. The dependence on temperature is subtle: pure water is denser at 4 Centigrade, not zero Centigrade (when it freezes, by definition of the Centigrade scale). Thus the water which sinks the most, and thus wiggles the most below ice, the 4C water, is plenty warm enough to melt ice.

The warm water comes from below, dragged by the current melting creates, and its higher density (caused both by its salt content, and the fact warmer water is denser, close to the freezing point, a weird fact of H2O). When it rubs along the ice shelf, it gets colder, hence less dense, all the more as it mixes with glacial sweet (thus less dense) water. (By the way, this creates inverted water channels scouring the ice sheets from below, and they can even be seen from the air.)

The Melting Of The Grounding Line Creates Surface Cold Water That Spreads Out

The Melting Of The Grounding Line Creates Surface Cold Water That Spreads Out

Thus, the more extended the sea ice is around Antarctica, at this point, the greater the evidence that the ice continent is losing cold, so to speak: it loses cold by spreading out at the surface of the ocean.

Something similar, on a much larger scale, caused a massive cooling of Europe 18,000 years ago (so-called Younger Dryas). Right in the middle of global warming, Europe froze for a millennium (due to the spread of cold water from Greenland melting, plus the subsequent short-cut of the Gulf Stream).

Here is a related fact. My friend Paul Handover called my attention on the following opinion I used to have:

“The melting of the ice sheet over Greenland is now a given. The ice sheets of West and East Antarctica a hair’s breadth from being a given.”

This is what I thought, say ten years ago. However I do not believe this opinion anymore: Antarctica will melt before Greenland. And nobody expects this.

Reason: it is easier to melt ice with warm water than with warm air, because the caloric capacity of water is much higher. Much of Antarctica, East and West is below sea level.

All the continental margin of Greenland is mountainous, and extends for hundreds of kilometers (mostly, although very long deep canyon have been found, lurking below the ice, in the last couple of years). In the case of Antarctica, the mountainous margins are either perfunctory and thin (WAIS), or inexistent (East Antarctica). This is why what was supposed to melt last, big time, East Antarctica may well melt first, big time.

Another factor, also overlooked, is that a lot of Antarctica’s coast is at pretty high latitude (hugging the polar circle), especially in East Antarctica, whereas only the mountainous tip of Greenland is south of the polar circle.

Here is the Geophysical Research Letters on 27 May 2014 about the catastrophic situation in West Antarctica: Widespread, rapid grounding line retreat of Pine Island, Thwaites, Smith, and Kohler glaciers, West Antarctica, from 1992 to 2011.

The grounding line retreat of glaciers draining the Amundsen Sea sector of West Antarctica was documented, using Earth Remote Sensing from European satellites (which went many times over their lifespans).

(ERS-1/2) satellite radar interferometry from 1992 to 2011 showed the following:

Pine Island Glacier retreated 31 km at its center, with most of the retreat in 2005–2009 when the glacier ungrounded from its ice plain. Thwaites Glacier retreated 14 km along its fast flow core and 1 to 9 km along the sides. Haynes Glacier retreated 10 km along its flanks. Smith/Kohler glaciers retreated the most, 35 km along its ice plain, and its ice shelf pinning points are vanishing. These rapid retreats proceed along regions of retrograde bed elevation (this means that, the further inland, the lower the ice plain below the glaciers; so warm water has a potential to fall DOWN towards the INTERIOR of the continent, as the future sea floor is crushed by the mass of the ice).

The team concluded: “Upstream of the 2011 grounding line positions, we find no major bed obstacle that would prevent the glaciers from further retreat and draw down the entire basin.”

A similar situation holds under the Ronnie Ice Shelf, east of the base of the Antarctica Peninsula. There again the Ice Shield rests mightily on an old ocean floor, sloping down towards the interior, to a depth of at least a mile. I don’t see why this sort of contraption cannot melt, and disintegrate, in a few years. I really don’t. Actually, I fully expect it. I don’t see how it could be otherwise.

This is the ultimate sucking sound… And something nobody very seriously employed as a “climate scientist” can afford to believe, lest she/he, wants to go live under a bridge.

Lest some will conclude that this is just a matter of a few billion people moving out of the way, please be reminded that the littoral is often where the best lands are.

But not just this. The assault of humanity against the biosphere are many, and some of these attacks are directed at the CO2 absorbing system. For example the Amazon absorbs only half the CO2 that it did, twenty years ago.

We need much more advanced technology, just to save the biosphere. Now.

Patrice Ayme’

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13 Responses to “West Antarctica Melting, Amazon Not Helping”

  1. EugenR Says:

    Are we on the tipping point???

  2. ianmillerblog Says:

    My view is that only a serious effort at geoengineering can save what we have. Even if we stopped burning carbon right now, the CO2 that is in the atmosphere would still take some time to be reduced to an acceptable level by plants, and we cannot stop burning carbon, at least not right away. The problem with geoengineering is that the planet is big enough that the effort will have to be done in some modest fraction of the planet, and that will have unknown consequences for many, or at least, that will be what only too many will say. Accordingly, nothing will be done except a few ineffectual attempts to reduce emissions. Unfortunately, since there is a net power input into the oceans right now, they will continue warming, and rising.

    Question: where do the Bangla Deshis go?

    • Paul Handover Says:

      In answer to your last question, they go to the same places as the rest of the 600 million in the world who are living less than 10 metres above the present sea level!

      It seems inconceivable to me that sufficient geo-engineering could be implemented in time (< 5 yrs? ) to prevent a runaway catastrophe. Sincerely hope I am wrong.

      • ianmillerblog Says:

        My thoughts were, places like New York will have US backing, a very rich country with plenty of spare land, so it is reasonable they can find somewhere. It will be ugly, but .. . Bangla Desh is very poor, and has very little spare land.

        I doubt all this will happen in less than five years [and I hope I am right 🙂 ] But even if it takes a hundred years, we have to start now. Actually, some geoengineering could be done very quickly, if we knew exactly what would happen for a given action. So in my view, we have to start some trial experiments very quickly.

      • Patrice Ayme Says:

        Dear Paul: Geoengineering to curb down CO2, is just propaganda. The only method I am sure would work without collateral damage is pure science fiction.

    • Patrice Ayme Says:

      Dear Ian: Good question about Bangladesh. Sea level is going up a centimeter a year there. Already (rivers and currents are affected by the warming, resulting in varying speed for the rise).

      There is no plausible geoengineering way to limit CO2.

      As you said, there is enough CO2 in the atmosphere for centuries of warming.

      Actually as I noticed in the essay, with the PRESENT CO2 level, temps were much higher in the Pliocene, Antarctica mostly non glaciated, and sea level up to 40 meters higher. That is what is in the pipe.

      The only question is: “how fast?”

      • ianmillerblog Says:

        Dear Patrice, I wouldn’t completely write off geoengineering yet, and because, as you say, there is a coming crisis, I feel we should at least try. To reduce CO2 there are two approaches. The first is to stop “slash and burn” of tropical rain forests and try to regrow them (and grow forests anywhere else they will grow). This at least offers a chance at fixing more carbon. The second is ocean fertilisation, to grow masses of algae. These could be harvested, in which case they are a rich source of chemicals for polymers, and a modest source of biofuel, which at least replaces fossil fuel. (This I know is quite feasible because I have done the chemistry.) Also, besides using photons that would otherwise heat water, they reduce CO2, and also sulphate, and thus reduces the heating effect of light on water. Further, and this is a bit more speculative, they should emit dimethyl sulphide into the atmosphere, which absorbs more photons and oxidises to sulphate, which in turn nucleates clouds, thus raising the albedo over the oceans, which again is a good thing. Do it in the right place, and it might generate more snow in the right place, which again raises the albedo.

        The other quick option is to spray salt water high in then air and make clouds, which again raises the albedo. Can this work? Maybe. Will it work? Nobody has any idea, but unless someone does the research to learn exactly what has to be done, it certainly will not.

        • Patrice Ayme Says:

          The soft approach you advocate (forests) would work. But, as you say, slash and burn is more vigorous than ever. A few year ago, Borneo was mostly equatorial forest. Now that is mostly gone, and the palm plantation to not have the same CO2 load perhaps by a factor of ten (just looking at them).

          Ocean fertilization looks gimmicky to me. It will sputter, because of ocean collapse.

          Making clouds is just fantasy. With which energy? Besides the main greenhouse gas is water. Clouds actually trap heat. As anybody who has slept in the desert (start of my life) can attest.
          PA

          • ianmillerblog Says:

            Ocean fertilisation could work. The US navy managed a system that self-supported itself (pumping up deep fertile water using wind power) in the 1970s, until a storm wrecked their engineering. Yes, clouds trap infrared, but they reflect UV/vis, so the planet is a net winner, or at least that is the theory. Salts in the atmosphere definitely help. One possibility I like is to put a little diethyl zinc into jet fuel – the contrails do cool what is underneath them, and microfine zinc oxide in the atmosphere may last for years.

            Agreed, some/all may not work. But does it hurt to try and put some real numbers on what happens? I think it is better to go down trying, than to simply sit there and take what is coming.

  3. Global Sea Ice Collapsing: Carbon Tax! | Patrice Ayme's Thoughts Says:

    […] https://patriceayme.wordpress.com/2015/03/21/west-antarctica-melting-amazon-not-helping/ […]

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