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by amorphid 3452 days ago
A few questions:

* How long will it take for "Deleware" to melt?

* Is ocean ice this large called an iceberg?

* Does is get an official name, like IIS Wilmington (international ice station, capital of Deleware)?

* Have large ice sheets in the past forced/caused changes in human behavior, such as altering shipping lanes, in the same way planes fly around a storm?

3 comments

> * How long will it take for "Deleware" to melt?

Potentially a very long time, although it will likely break into smaller pieces first. A lot of icebergs get caught in the Antarctic Coastal Current, and just drift around the edge of Antarctica, not melting very much at all. Over time, most of them break free and drift north into warmer waters and melt, but others stick around. Iceberg B-9, which calved in 1987, still has a few chunks sitting around.

> * Is ocean ice this large called an iceberg?

Yes. You'll sometimes see the bigger bergs described as "ice islands", but that's just a subcategory of iceberg.

> * Does is get an official name, like IIS Wilmington (international ice station, capital of Deleware)?

It'll get a numeric designation, A-nn, where A indicates which quadrant of Antarctica it originated from (in this case 0-90W) and nn is a sequential number, probably in the high sixties depending on whether any other large bergs calve first. Then, as it breaks up, the resulting bergs will get letters added to the name, A-nnA, A-nnB, etc.

> * Have large ice sheets in the past forced/caused changes in human behavior, such as altering shipping lanes, in the same way planes fly around a storm?

In 2005, B-15A blocked the entrance to McMurdo Sound, where the main US and New Zealand Antarctic bases are located, and they were unable to get cargo ships in for a few weeks. And of course, ships are redirected around icebergs in the open ocean all the time.

> Iceberg B-9, which calved in 1987, still has a few chunks sitting around.

Thanks for posting, and curious about this. When icebergs subdivide, how is tracking accomplished?

I assume late 80s was recent enough for decent resolution space imagery?

Yeah, once these things are moving, you don't need much resolution to see them - we're talking about objects several kilometers wide, at the very least. Easily visible on even the most primitive satellite imagery. The difficulties would be cloud cover and orbital inclination.
> I assume late 80s was recent enough for decent resolution space imagery?

Landsat (https://en.wikipedia.org/wiki/Landsat_program) was likely the best available imagery back then. In the 80's it looks like they had 60m resolution - I assume that would be big enough to see an iceberg?

I'm not an expert on icebergs but I have used enough satellite imagery to answer... Yes the 60m Landsat imagery would show large icebergs under its ground track.
Thanks!

That bit about McMurdo is interesting. I doesn't surprise me, but I didn't know, that they send and receive thinhs via ships. I always hear about McMurdo as being inaccessible by plane during some chunk of time during the cold season, usually tied to some real world emergency or movie plotline with a sense of urgency.

  Potentially a very long time, ...
Am I the only one who is concerned that a scientist wouldn't immediately comment that this is irrelevant with respect to effect on sea level? Once any body of ice is free-floating, its effect on sea level is immediate and doesn't get worse as it melts.
It's almost like the conventional terminology for bergs (http://www.ccg-gcc.gc.ca/e0010735) might need to be expanded for these monsters. Some of them may as well be floating glaciers.
FYI, Dover's the capital of Delaware.

(pedantic Blue Hen here.)

My bad :). My head said Dover, and my hands wrote biggest city I could remember. Don't tell my 8th grade U.S. History teacher. He'd have an anuerism.
Or your spelling teacher (aneurysm)
Don't tell his spelling coach either!!
Wouldn't your geography teacher be more annoyed than your history teacher, or have I missed the point?
My U.S. History teacher grilled us every week on knowing US states & their capitols. You have to show weekly improvement, and finish the term w/ 100%.

Regarding spelling, I plead not guilty by reason of autocorrect+gorilla-fingers-on-little-screen.

In some schools (like mine) we did a geography segment as part of the history class. So same teacher, primarily teaching history.
Will there be a man made ravine breaking it into northern & souther halves, though?
> Have large ice sheets in the past forced/caused changes in human behavior

Not human in this example, but they can be devastating to penguin populations:

https://www.theguardian.com/world/2016/feb/13/150000-penguin...