Questions tagged [ice-sheets]
[ice-sheets] concerns questions on the large present and past continental scale ice sheets, such as Antarctica, Greenland, the Laurentide, Fennoscandian and Alpine ice sheets.
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Were sub-sea river channels formed when the land was above sea level?
In this satellite pic, on the land is the Columbia river on the western side of North America.
I was amazed to see the channel within the sea, more than 125 km long.
Can it be concluded, based on ...
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Why was the ice age more severe in North America than in Eurasia?
I've been looking at reconstructions of the extent of ice at the last glacial maximum, while each map differs slightly (two shown below), most show a massive North American ice sheet, extending as far ...
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How was the sea depth under the North Pole ice sheets measured?
Google Earth doesn't show the ice sheets of the North Pole, but the undersea depth. How was this depth measured, when most of this area is covered by ice all year round?
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From ice core analysis to temperature curves
In ice cores a lot of data are measured and analyzed and can be plotted versus depth, for example
age of layers
thickness of layers
concentration of spurious gases
concentration of solids
delta ...
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Last ice age: did glaciers move South or move downhill?
(Note: this is from U.S. point of view)
I keep hearing how the glaciers "moved South" during the last ice age. But I thought glaciers moved downhill.
I can see that the glaciers formed ...
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How are mGal-smooth free-air gravity anomaly measurements made exactly? (tiny variations of acceleration on a bumpy airplane ride)
Free-air gravity anomaly measurements from Operation Icebridge aircraft are described in A fault-bounded palaeo-lake basin preserved beneath the Greenland Ice Sheet (open access).
Question: These ...
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Has Antarctica's coastline been completely mapped? (map discrepancies)
Looking at different world maps, I noticed that there is considerable variety in how the coastline of Antarctica is depicted (even when taking the different map projections into consideration).
Are ...
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Ice cores: how is Oxygen-18 isotopic variation converted to temperature changes?
The Dansgaard paper I've seen shows a roughly linear relationship between the delta-O18 in precipitation and mean annual temperature (at a given location). See Figure 3 in the paper.
When converting ...
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Have russian drilling operations in lake Vostok succeeded yet?
A couple of years ago the russians began drilling through about 2 km of ice to reach lake Vostok in Antarctica. It was hoped that they would find living organisms there which had been entombed under ...
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A better way to prevent ice shelf from melting and raising ocean levels?
I just read this article by scientist who propose making giant snow machines to basically move the eroding ice shelf further inland. It’s been described as pretty much cost prohibitive (despite saving ...
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Help understanding radar data in subglacial lake complex beneath Devon Ice Cap
The BBC News article Isolated lakes found beneath Canadian ice sheet links to the open access Science Advances article Discovery of a hypersaline subglacial lake complex beneath Devon Ice Cap, ...
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How does ice-penetrating radar "see" through kilometers of ice without being absorbed?
The BBC News article Isolated lakes found beneath Canadian ice sheet links to the open access Science Advances article Discovery of a hypersaline subglacial lake complex beneath Devon Ice Cap, ...
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Would the enthalpy of fusion for melting ice fields be a causative factor for colder winter weather?
Would the enthalpy of fusion for melting ice fields be a causative factor for colder winter weather?
As an example, NASA estimated the annual loss of the Greenland ice field 2002-2013 as more than ...
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Considering how old the Antarctic ice cover is, why isn't it much thicker?
The Wikipedia article on the subject of the "Antarctic ice sheet" says that:
The icing of Antarctica began in the middle Eocene about 45.5 million
years ago and escalated during the Eocene–...
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Can ice caps reform if they disappear?
Excuse my ignorance. I'm under the impression that there are various types of ice at the poles, but I don't know the difference or the significance of each type, so, in terms of whatever is actually ...
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Will increased precipitation in Antarctica prevent sea level rise?
It has been suggested that global warming will lead to increased precipitation in parts of Antarctica. This would sequester water in the ice sheet, preventing sea level rise.
However, the slope (and ...
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How much of the ice on earth is floating?
How much of the ice on Earth is floating (such as icebergs, or perhaps all the ice up at the North Pole)?
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Did the surfaces of the oceans freeze over entirely during the snowball Earth periods?
According to the snowball Earth theory, all of Earth froze over at least once (possibly twice) in the far past. However, Wikipedia says that there are opponents of the theory who state that tropical ...
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At what rate are the polar ice caps shrinking?
At what rate is loss of polar ice caps occurring? Do we have enough data to distinguish a meaningful trend? If we look at the trend since we have satellite measurements (40 years or so), is that ...
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What is more important in Antarctica calving or basal melting of the ice shelves?
Ice shelves are present along 75% of Antarctica coast and cover over 1.5 million km2. The two main processes causing mass loss of the ice shelf are basal melting and calving. Which of the two ...
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Why is relative sea-level falling in Hudson Bay?
Why is the sea level in Hudson Bay decreasing so much? Hudson Bay is pretty far up north, much closer to glaciers. Would it make sense for it to recede at this level with sources of fresh water ...
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How strong can a glacial icequake get?
While researching Antarctic geology, I came across the term 'icequake' in the abstract to the article Seismicity within a propagating ice shelf rift: The relationship between icequake locations and ...
user889
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What geophysical knowledge have we learned by the construction of IceCube?
The IceCube is a particle detector at the South Pole that records neutrino interactions. It has lead to many fascinating new discoveries in the field of astrophysics (e.g., 1, 2) and it was awarded "...
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How deep is the permafrost in the Antarctic?
I tried in vain to find the answer to this question on the web, but all it would tell me was, "it is very deep", and "it is known as a thaw line rather than a frost line in the arctic and antarctic". ...
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Glaciology: odd pattern of smooth and ribbed chunks of ice in Antartica
At -69.184611, -68.124276 (just east of the Bugge Islands) there is a triangular ice shelf. On satellite images (as seen on Google/Bing maps) you can see it is riddled with --for lack of a clearer ...
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What evidence is there linking melting ice caps and changes in tectonic movement?
Reading one of my other questions, How much would the Greenland landmass isostatic rebound contribute to long term climate change?, a subsequent question is what, if any, effect the isostatic rebound ...
user889
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Can earthquakes contribute to Antarctic ice loss?
I read about the earthquake that took place in Japan in 2011, led to some small calving events in Antarctica (link). So, it makes me think if there is a big earthquake near or in Antarctica, can it ...
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How are the thickness of ice sheets from previous glaciation periods determined?
How is the thickness/depth of ice sheets from previous glaciation periods determined? I've for instance often seen statements that the ice sheet over Scandinavia at the last glacial period maximum (i....
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Where does the biggest land-based ice cap reside?
I'm thinking biggest in volume, regarding which area of the planet will contribute more to a raising in sea level - were the ice in those regions to melt.
I can basically think of two candidates, ...
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How long to melt all the polar ice?
The answers to this question say that the sea level will rise 66m if all the polar ice, etc, melts.
How long will this take?
Transporting incredible amounts of heat energy to the poles and injecting ...
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How much will sea level rise if all the polar ice melts?
There are many movies about global warming, which say that melting of all polar ice would cause the whole world to suffer a huge flood. According my research (teachers, TV, Internet) people hold one ...
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