Posts Tagged ‘East Antarctica’

East Antarctica Melting

March 20, 2015

SHALLOW SEAS COMING ALL OVER:

East Antarctica Melting Could be Explained by Oceanic Gateways

Antarctica is very cold. Most of it is always frozen. So why are some country-sized glaciers there, thinning by six meters per year? Enquiring minds want to know.

This thinning was not anticipated, by common scientists. Apocalyptic considerations do not advance academic careers. However it looked ineluctable to yours truly, long ago:

https://patriceayme.wordpress.com/2009/05/31/sun-cooling-ice-melting/

The naïve had bellowed that East Antarctica would not melt for thousands of years. I pointed out that vast swathes of the ice continent were below sea level, and would melt in a geological instant, if warm water got below. This is exactly was is happening.

Let me have the pleasure to present to you the outlet of the Totten Glacier, hundreds of kilometers long, and fifty kilometers wide:

Warm Water Flowing Through Narrow Red Marks (5 Kms Wide). I Melt, You Drown.

Warm Water Flowing Through Narrow Red Marks (5 Kms Wide). I Melt, You Drown.

As I said, this is just the outlet of the Totten Glacier. As the picture below shows, most of the glacier is in the interior, and it is hundreds of time greater in area… And volume. More troubling, its bottom is miles… under water. Many glaciers of Antarctica, East or West, rest kilometers below sea level. (Much of the interior of Greenland is also below sea level; it is entirely possible that the sea could enter, too; a grand canyon was just discovered there.)

The reason is the weight of the ice. Two miles of ice press down with 3,000 tons per square meter. Over a square kilometer, that’s three billion tons. As continents float on a liquid layer which rests on something viscous, continental masses sink under the ice (“isostasis”). Conversely, 10,000 years after the disappearance of the ice, Scandinavia is still lifting up.

The euphemistically named “climate change” see even a drying California’s Sierra Nevada, going up: a drying Sierra is lighter than a wet Sierra.

So what is going on with these East Antarctica glaciers? Let’s consider Totten.

The “catchment basin” of the Totten glacier is larger than California. It firmly rests on the continent with depths as great as more than two miles below sea level (nearly four (4) kilometers!). I warned explicitly, six years ago, that it would melt soon, with the exact mechanism now revealed as being in full swing.

This Will All Melt. Map Above, The Entrance of Totten, Is The Red Rectangle

This Will All Melt. Map Above, The Entrance of Totten, Is The Red Rectangle

The coast of East Antarctica hugs the Polar Circle. Thus, it is not that far south. It is potentially exposed to warm waters. It is roughly at the same latitude as Iceland, a place where forests are growing again.

All this ice is protected by, or used to be protected by thick frozen lips, next to the Antarctic Ocean. (Reason: on the margin of the continent, there is no more ice, or then floating ices shelves; thus, there is no more weight pressing down, and the continent flexes back up, forming the lips; I made up the word “lip”, by the way).

The frozen lips used to be stuck with giant ice plugs. Those are melting, or, in the case of Totten, have melted, and relatively warmish water is increasingly circulating below. (The reason is that warm salted is denser than colder sweeter water; so warm water passes below.)

If the warm water passes the threshold, the lip, it will fall on the other side, below the giant glacier, or, as it called, the icecap.

The warm water has advanced below the Totten Glacier by hundreds of kilometers, and has lifted the glacier. The line where the glacier is still resting on the continent is called the “Grounding Line”.

The study published in Nature was the result of cooperation from NASA, ESA, USA, France, UK, Australia, and more than 100 scientists. East Antarctica Melting Could be Explained by Oceanic Gateways

 

The Grounding Line can be picked up on ice penetrating radar. Such radar can distinguish the polished ice lifted and melting, and the grounded ice.

It is known that the entire Totten basin has melted in the past. One has to understand the human species evolved in the last two million years or so, roughly coincident with the freezing of Antarctica.

Why, when did Antarctica freeze? When the CO2 density fell below 450 PPM. Now it’s 400 PPM, if restricted to CO2.

However, in truth, we are well above 450 PPM, because one has to count the other man-made greenhouse gases (which did not exist when Antarctica started to freeze three million years ago).

So now Antarctica is unstable. As a frozen continent.

The warm water is not just lifting the glacier, but melting it. From below. When the glacier is entirely melted, all the ancient water molecules frozen above sea level in the past will rejoin the oceans. And the oceans, in turn, will rise.

A secondary effect is that, as the sea level rises, the ice shelves will get pushed up. As this happen, they will fracture, and melt even faster than expected. This will have an effect especially on West Antarctica, much of it been anchored by giant ice shelves.

Antarctica, and Greenland, if they thoroughly melted, would stay melted. Forests would grow (they started to, in Greenland).

Scientists are reassuring: if the Totten glacier melts completely, it will take centuries. They look at each other, and opine. I can hear them bleat from here. They have to be reassuring, because they are Very Serious People, on whom plutocracy leans.

It is the same crowd who, six years ago, was absolutely sure East Antarctica would never melt.

Yet, it is melting.

I will not bother to roll out mathematics and compute. Take California, cover it with two miles of ice. Then direct at it cold water, with a hose, five miles wide, half a mile deep. How long? Ah, a detail that may not be a detail: it’s coming from below. With ice shelves, lifting from below induces their brutal disintegration. The same happens with flowing glaciers. The spectacle is nearly incomprehensible in its violence and gigantism.

So watch this video, of the largest calving event ever filmed:

https://www.youtube.com/watch?v=hC3VTgIPoGU

This is the future of the Totten glacier, soon, and on a wide, getting ever wider, front.

No, it will not take centuries.

Decades, at most.

Melting Totten will change human civilization, forever. And of course, it will not melt alone. As I showed in detail, six years ago, there is an ever larger catchment basin in East Antarctica, with its bottom miles under sea level

Patrice Ayme’