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39

Water has lowest EM absorption in the blue part of light spectrum and increases rapidly towards both UV and red parts of spectrum. As a result in visible light water is blue. Same goes for the ice as it has very similar absorption spectrum. While there is a lot of white in the picture, all of it is a thin snow cover on top of blue ice. Once the snow ...


15

"Transparent" is not the same as "white" : white bodies reflect most of the light while transparent bodies let the light though. Once the light enters into water, it may need to travel a long way before it has a chance to go out, and that long travel path provides more opportunities for absorption. Water absorbs light by itself much more than snow, but ...


10

You probably realise this, but you're not seeing that directly from satellite photos. Google Earth (or the "satellite" view in Google Maps) shows direct imagery on land, but underwater it shows a hillshaded view of bathymetry. So you're looking at the shape of the seabed. With that said, I think this is the nothernmost part of the Mid-Atlantic Ridge, ...


7

The fact that these three features are parallel may be somewhat coincidental, although we can suspect that tectonic forces have influenced their morphology. The crust under the Arctic Sea is one of the least understood regimes in the world. This is changing - whichever country can prove that their nation's continental shelf extends along one or more of ...


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

The IPCC said "Although the Hadley Centre climate model underestimates sea-ice extent and thickness, the trends of the two models are similar. Both models predict continued decreases in sea-ice thickness and extent (Vinnikov et al., 1999), so that by 2050, sea-ice extent is reduced to about 80% of area it covered at the mid-20th century." The graph on this ...


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 ...


4

Helium is formed through the radioactive decay of uranium 238, uranium 235 and Thorium 232. A helium atom is an alpha particle that has collected electrons. The only way that helium is produced on Earth is by such radioactive decay deep underground. Generally, the helium travels along cracks until it reaches a subterranean cavern where it accumulates. ...


4

The specific 36 F temperature anomaly in the linked article points to a single day event. I am aware that it is associated with unusually high temperatures in general this fall/winter, but a single day event is not that unusual. For example, the average January temperature in Dallas is 46 F, and the average monthly high is 76 F. That means every year (on ...


4

The wavelengths that travel through the ice have a faster speed of travel, and the physical size of the pressure variations that cause the sound are not 100 meters. It's more like 1 meter, so it's similar to having an oversized speaker cone blasting air waves into the ice, which the ice then transmits to the microphone most clearly at a depth of 1-2 meters. ...


4

The box in the lower left of the bottom chart is key to understanding what is presented. Five attempts of a line of best fit have been presented. From the chart, the linear fit (yellow line) is the least best fit, so the loss of Arctic ice not a linear relationship. The other lines are different modeling scenarios the author has attempted. When testing for ...


3

The agricultural regions of Canada: are located on suitable soil types: Much of the unfarmed area is the Canadian Shield (shades of red below): The current surface expression of the Shield is one of very thin soil lying on top of the bedrock, with many bare outcrops. This arrangement was caused by severe glaciation during the ice age, which covered ...


3

Wikipedia does not include Alert as a port. As the comments suggest, there is too much sea ice at that latitude to merit the infrastructure required of a port. The northernmost port in the world is identified here as Dikson, Russia, at 73°30' N. Supplies to Alert are delivered by air; the settlement does include an air port.


3

There are no "True" curves in the extent that there is no theory or physical laws that link the number of years with the disappearing of arctic ice. (These several curves are only interpolation models, they give a trend: only additional measure points would give us a more accurate fit.) Based on other variables, we could imagine such a law depending on : ...


3

You can follow the sea ice extent here at http://polarportal.dk/en/sea-ice-and-icebergs/ And here at http://nsidc.org/arcticseaicenews/ There is a lot of things you can not see in regular maps as they fill in the area with ice as open sea on their products,It is the same for land areas too they do not change the maps if the ground is covered by snow. So ...


3

I don't know where you get the 36 degrees from - it seems rather extreme. Do you mean 36 deg F = 20 deg C? Even 20 is not realistic, except perhaps for a very short period anomaly. In fact, the average temperature increase in the north pole area is little more than 4 degrees C. see https://nsidc.org/cryosphere/arctic-meteorology/climate_change.html In ...


2

What would you have an Antarctic rover do? How would you protect it from falling down a crevasse, some of which are totally obscured? What would you like to be found in Antarctica? Yes, Antarctica is a large snow and ice covered island. The ice being up to 4500 m thick. The analysis of Antarctic ice cores is allowing scientists to discover the composition ...


2

Concerning datasets, there are several, depends on Your final purpose. One of the simplest is output from OSI-SAF, which has info about Sea Ice edge, concentration, type, emissivity and drift. It is derived mostly from polar orbiting meteorological satellites, I guess. More detailed info can be found on Univ of Illinois pages Visual images from MODIS ...


2

We actually expanded those two papers into a peer review paper located here. https://www.hindawi.com/journals/amete/2017/1765428/ In it you can find our success of finding 2sd situations 70% of the time. Also, might I suggest looking at a website that has quite a few options like 500mb/surface map overlays along with verification situations. http://www....


1

Water (solid or liquid) has some absorbtion. It is rather low for pure water for visible or near-visible light and that's why water it is considered transparent. But only to an extent - few meters of water look blue and few hundred meters look black, esp. if you are UNDER those few hundred meters. Then we have snow. Snow has an abundance of optical ...


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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