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Thursday 19 October 2017

Lambert Glacier -- a thing of beauty


There are few things on this planet more impressive than a big glacier in full flow.  This is the Lambert Glacier in Antarctica.  It flows into the Amery Ice Shelf.  Click to see the image enlarged.

At the base of this NASA image, it is about 30 km wide, but at the big confluence with Fisher Glacier it is about 60 km wide.  Across most of the area shown in the image, the glacier velocity is between 500 m and 800 m per year, but the velocity speeds up as the ice gets towards the ice shelf, with a flow rate of c 1 km per year.    Surging glaciers sometimes move faster than that, but this is assumed to be the fastest-flowing big outlet glacier on the planet.

The streamlines or flowlines are shown here in extraordinary detail.

 Here is another image -- this time from Google earth.  You can see many of the same features.





8 comments:

Dave Maynard said...

Nunataks! I thought of the word and I was right when I looked it up.

What are the things on the surface between the 'L' of Lambert and the Mawson Escarpement? Are they small rock outcrops or lumps of ice on the surface of the glacier, or maybe even hole in the glacier?

Dave

BRIAN JOHN said...

Yes, nunataks all over the place! That area you refer to looks to me like an area of thin ice -- if you look you can see the surface undulations, similar to that which you see sometimes on ice caps or inundated uplands. I don't think there are any ablation or meltwater pits just there -- maybe just areas where hill summits are almost breaking the surface.

TonyH said...

Nunataks!

Believe it or not, it is true I have discussed nunataks over coffee after a Service at Trowbridge Parish Church. The reason being (if you ever needed a reason) that the Church had recently welcomed into its congregation a retired minister, who had been vicar of an Inuit town on the Arctic Ocean coast, within Canada's Diocese of the Arctic - one of the largest Anglican Dioceses in the world.

There are possible remnants of nunataks in West Wales, are there not?

BRIAN JOHN said...

Tony -- Strange -- acc to my computer it was posted, but somehow disappeared into the ether....

Anyway, plenty of nunataks in Arctic Canada -- and there were some in Pembs as well. Try putting "nunatak" into the search box....

TonyH said...

Yeah, I knew we'd mentioned them. Perhaps someone, such as you, should take MPP & his Merry Men/Women on a field trip next September? Or Peter Dunn, who comments on here, and has done artistic reconstructions of Stonehenge etc for the Stonehenge Riverside Boys & Girls. A bit of glacial geomorphology identification to assist with their imaginative ideas?

Glaciation so often seems to be the Elephant in the Room at least for these particular archaeologists.....

TonyH said...

"Some nunataks in Pembs as well"........such as CarnIngli, on Brian's doorstep! (he has a Post on it).

TonyH said...

I have also discussed pingos - circular raised features - with my retired Arctic Minister friend (Durham University graduate).

Very interesting Post or two on the Blog, e.g:-

25th April 2015 Pingos/ Circular Enclosures in Cardiganshire

BRIAN JOHN said...

Yes, pingos, nunataks etc -- they are all on the blog somewhere. That;s one reason why we get so many hits on this blog site-- things keep on coming up when students from all over the world do google searches.