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Re: Dynamic Planet B/C

Posted: November 17th, 2018, 8:26 am
by Things2do
What is the name of the current epoch?

Re: Dynamic Planet B/C

Posted: November 17th, 2018, 9:39 am
by linzhiyan
Holocene?

Re: Dynamic Planet B/C

Posted: November 17th, 2018, 4:36 pm
by Things2do
linzhiyan wrote:
Holocene?
Sounds right...

Re: Dynamic Planet B/C

Posted: December 18th, 2018, 10:13 pm
by Umaroth
I will revive this topic since this is pretty much my favorite event :D

Which other ice sheet covered parts of North America during the Pleistocene Epoch alongside the Laurentide? Where did the two merge?

Re: Dynamic Planet B/C

Posted: December 19th, 2018, 4:58 pm
by cacodemon
Cordilleran merged with Laurentide at continental divide
In 2002, a volume of roughly 7.15 x 10^5 km^3 rapidly disintegrated from the Larsen B sector of the Larsen Ice Shelf.
By how much did sea level rise due to this event only? The density of ice is 917 kg/m^3 and density of water is 997 kg/m^3.

Re: Dynamic Planet B/C

Posted: December 25th, 2018, 9:17 am
by sciencegirl03
cacodemon wrote:
Cordilleran merged with Laurentide at continental divide
In 2002, a volume of roughly 7.15 x 10^5 km^3 rapidly disintegrated from the Larsen B sector of the Larsen Ice Shelf.
By how much did sea level rise due to this event only? The density of ice is 917 kg/m^3 and density of water is 997 kg/m^3.
Isn't this more of a Fermi Question :lol: ?? Haha anyway...:
1.827 meters...basically I used d=m/v to find out the mass of the ice since we had its volume and density, and then using that mass, I found out the volume of water that would take up. Then, I set that volume equal to the surface area of Earth's oceans x a variable for height, to solve for the height that volume would take up if spread over all of Earth's oceans.


Hope i got it right!
Next question:
What is a grounding line, and how does it relate to ice shelves?

Re: Dynamic Planet B/C

Posted: December 28th, 2018, 3:54 pm
by SciolyHarsh
The grounding line is the point at which the ice shelf starts to float on the water. This is only for tidewater glaciers iirc. Hopefully my answer is correct.
Question: Suppose a large area of continent consists of 30 km of Earth’s crust with a density of 2.6 Mg/m³ over 90 km of material with a density of 3.0 Mg/m³. The asthenosphere density is 3.3 Mg/m³. This region is covered with a 1.5 km thickness of ice of density 0.9 Mg/m³ and is assumed to be in isostatic equilibrium. If the ice melts, how much will the surface of the continent change once isostatic equilibrium is re-established? Answer in kilometers.

Re: Dynamic Planet B/C

Posted: December 29th, 2018, 8:41 am
by sciencegirl03
SciolyHarsh wrote:The grounding line is the point at which the ice shelf starts to float on the water. This is only for tidewater glaciers iirc. Hopefully my answer is correct.
Question: Suppose a large area of continent consists of 30 km of Earth’s crust with a density of 2.6 Mg/m³ over 90 km of material with a density of 3.0 Mg/m³. The asthenosphere density is 3.3 Mg/m³. This region is covered with a 1.5 km thickness of ice of density 0.9 Mg/m³ and is assumed to be in isostatic equilibrium. If the ice melts, how much will the surface of the continent change once isostatic equilibrium is re-established? Answer in kilometers.
That's right!

Re: Dynamic Planet B/C

Posted: December 29th, 2018, 12:57 pm
by cacodemon
Nope, somewhat of a trick question.
Sea level would not change. An ice shelf is floating on water by buoyancy -- sea level rise is proportional to volume of water displaced. So when the ice shelf melts, there is no change in sea level because the water displaced by the ice shelf is filled by the volume of water that ice shelf represents. Sea level changes when ice on land melts and either runs off or sheds directly into the ocean as icebergs.

Re: Dynamic Planet B/C

Posted: December 29th, 2018, 2:38 pm
by UTF-8 U+6211 U+662F
SciolyHarsh wrote:Question: Suppose a large area of continent consists of 30 km of Earth’s crust with a density of 2.6 Mg/m³ over 90 km of material with a density of 3.0 Mg/m³. The asthenosphere density is 3.3 Mg/m³. This region is covered with a 1.5 km thickness of ice of density 0.9 Mg/m³ and is assumed to be in isostatic equilibrium. If the ice melts, how much will the surface of the continent change once isostatic equilibrium is re-established? Answer in kilometers.
cacodemon wrote:Nope, somewhat of a trick question.
Sea level would not change. An ice shelf is floating on water by buoyancy -- sea level rise is proportional to volume of water displaced. So when the ice shelf melts, there is no change in sea level because the water displaced by the ice shelf is filled by the volume of water that ice shelf represents. Sea level changes when ice on land melts and either runs off or sheds directly into the ocean as icebergs.
But it is asking about the surface of the continent, not sea level: the glacier is not in the ocean.
0.41 km?