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33

Using the latest numbers from the 2013 IPCC report (Ch. 4, the Cryosphere), Antarctica contains 58.3 m of sea level equivalent (sle) and Greenland 7.36 m sle. Remaining glaciers provide an additional 0.41 m sle. In total and adding very minor contributions from permafrost etc. the total comes out to approximately 66.1 m sle. EDIT: Just to be complete: If ...

29

The short answer is: BECAUSE THE ICE IS BLUE. Now we have to explain why it seems perfectly transparent on ice cubes and industrial ice blocks. It has to do with the fact that most transparent materials are not perfectly transparent, and instead absorb (and/or scatter) part of the light that hits them. And when the transparency is better for one specific ...

25

That's is due to the slow diffusion of heat into the ground. Unlike a liquid, pieces of soil can't move around, therefore, in the absence of liquid water, heat can only be transferred by conduction, a process that follows the diffusion equations and it is very slow. This means that if there is a heat wave, or a cold snap, their effect will reach deep layers ...

21

Antarctic sea ice extent for April 2014 reached 9.00 million square kilometers (3.47 million square miles), the largest ice extent on record by a significant margin. Is there any explanation for such an extreme excess of sea ice around Antarctica recently? I'll give four separate answers: It's not as significant an increase as you think. The ...

17

Indeed some glaciers are growing and gaining mass due to increased precipitation (in part due to climate change and enhanced atmospheric water content). But that's the case only for glaciers in very cold places, like East Antarctica, where most glaciers appear to be growing at increasing rates (1,2). But unfortunately West Antarctica is pretty much a desert; ...

16

As Peter Jansson explains, sea level rise purely due to melting of land-based global ice works out "to approximately 66.1 m sle." An issue with respect to sea-level rise that isn't often mentioned (especially not in disaster movies!) is that thermal expansion of the sea - i.e. water expanding as global temperatures rise - will also have a huge effect: see ...

13

Some background. The idea of towing ice bergs to provide a source for fresh water in dry climate zones was first proposed in the 1970s by Weeks and Campbell (1973) and Hult and Ostrander (1973). This sparked interest that resulted in several studies published in conferences (Husseiny, 1980; IGS, 1980). The focus of the work was manly on the wastage of ice ...

13

This question has already been answered on Skeptics.SE: Did the Arctic Ice Sheet grow by 60% from 2012 to 2013? The short answer is that those two graphs are consistent with each other. The first shows a 33 year trend of declining Arctic sea ice (summer minimum, I think), whereas the second highlights inter-annual variation in Arctic sea ice over the last ...

11

(I can't comment on @kaberett answer as a guest) Don't forget the odd effect that as ice melts and the water warms from 0C to 4C, that water will contract slightly, dropping sea level a bit (at least, locally). Once it gets above 4C, it will start expanding again. If the oceans overall cool a bit due to cold meltwater mixing in, they too will contract until ...

9

As Peter Jansson pointed out, it adds up to 66.1 m of sea level rise. But what does that really mean for us? Here's a nice interactive map tool where you can enter how much the sea level will rise and see what that does to our coast lines. So crank it up to 60m and look around. Obviously, The Netherlands will disappear almost entirely, as will most of ...

9

(Note: this is based on what I found in literature. Sea ice is not my expertise.) Short answer: We don't know. It may be related to changes in atmospheric temperature, wind stress, precipitation, ocean temperature, changes in coastal polynas, or other factors. The usual way to explain observed behaviour is through models. However, models are currently ...

7

A first-order estimate is about 5%. This is a trickier question than it first appears because of ice shelves. Quoting from Kusky (2014): Ice shelves form where ice sheets move over ocean waters and form a thick sheet of ice floating on the water and attached to the land on one, two, or three sides. Their seaward sides are typically marked by a steep ...

7

While @kaberett's and @Phil Perry's answers are technically true, keep in mind 2 important issues: the oceans are so vast and so deep that it literally takes decades if not centuries for them to warm up or cool down. This is called Thermal Inertia - see a much more in-depth explanation about it. Basically, you'll only see the effect of current rising ...

7

I'm assuming this question is asking about the sea ice in the Arctic Ocean as opposed to ice caps such as that over Greenland. The sea ice on the Arctic Ocean is predominantly (overwhelmingly!) frozen ocean water. The Arctic Ocean loses 17 to 18 thousand cubic kilometers of ice every summer, only to regain most of that melted ice during the long Arctic ...

6

If we consider only the climatic impacts of Arctic coastal erosion, there are still two sides of the question of how relevant is Arctic coastal erosion of permafrost. The first side is how big is its current role as a ${CO}_2$ source, and the second is how much of risk it posses for future climate change. It term of current contribution the answers is that ...

6

Yes, a layer of snow on top of ice can melt in some circumstances. For example, one active area of climate research involves analyzing the optical properties of sea ice as they relate to incoming solar radiation. In some studies (e.g., Ehn et al. 2004) this involves snow layered on top of ice, with the snow explicitly melting (and later refreezing) over the ...

5

Few things to notice are that while the Arctic Sea volume increased 50%, the volume increase was marginal compared with the volume of sea ice in 1979. Next, if you review the graph below, one year spikes are not that unusual, though if there was another 50% the volume increase from 2013 to 2014, it would be of note, given the rarity of significant year over ...

5

Permafrost is permanently frozen ground. However, most definition qualify it as permafrost if it remains frozen for at least two years. The speed at which a temperature change travels down the ground depends on the thermal conductivity, and it varies between soils. As a thumb rule, the temperature at 10 m depth is pretty much constant and equal to the mean ...

4

Yes, they have many impacts: They provide a substrate for algae to grow and they can have whole ecosystems under them. You might think that such substrate is transient because it is melting, but Arctic and Antarctic waters are often below zero degrees Celsius, therefore, freshwater ice doesn't melt. You can find many articles about such ecosystems (here is ...

4

I had been to a conference at the NY American Museum of Natural History and the guest speaker at the science convention estimates about 220-230 feet (66 - 69 meters). If the polar ice caps melted, how much would the oceans rise?

4

More moisture in the atmosphere also means less orographic lifting is required to reach saturation. This should lead to rain or snowfall at lower elevations, where it would melt more rapidly and not contribute to snowpack.

3

I looked at trends in Antarctic sea ice extent in the satellite era from 1979 to 2015 for both the summer minimum (February) and the winter maximum (September) and did not find a statistically significant trend. Please see: http://papers.ssrn.com/sol3/papers.cfm?abstract_id=2598152

3

A little Google searching and I found this: Source: https://nsidc.org/cryosphere/sotc/snow_extent.html Snow-cover is considered an important factor in climate change study, so it's tracked pretty carefully. There's probably a specific average minimum date out there somewhere if you're really interested but I didn't see it. Judging from the chart, ...

2

Mountains are a little unusual in terms of water vapor capture. Temperature drops with elevation so some mountains have ice-cover even in summer and/or even in warm latitudes. Mountain ranges tend to block air-flow and if there's a prevailing wind direction, it's not uncommon for for the other side of the mountain to be desert. This is called a rain ...

1

Were to find hourly data will depend on your location, as you will probably need to access the national weather network of the country of your interest. Global climatic databases usually record data on daily basis. Like the Global Historical Climate Network, you can search for all the station in that network and query snowfall data in the KNMI Climate ...

1

SANDIA REPORT“The Arctic Coastal Erosion Problem”by Sandia National Laboratories, SAND2016-9762, September,2016 "One-third of the coastline in the world is Arctic permafrost [Lantuit et al., 2012]. Despite this sizeable proportion, a comprehensive understanding of erosion dynamics in the Arctic has not yet emerged. Unfortunately, the majority of present ...

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