# What if the Earth was rotated? **URL:** \ **Category:** Factual Questions\ **Created:** [September 24, 2010, 6:33pm UTC](https://boards.straightdope.com/t/what-if-the-earth-was-rotated/554914 "2010-09-24T18:33:12Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [September 24, 2010, 10:22pm UTC](https://boards.straightdope.com/t/what-if-the-earth-was-rotated/554914/21 "2010-09-24T22:22:39Z")
> [@Quartz](#): > > Is the axis of rotation pointing at the sun or is it tangential? In the former case, the sunward side of the Earth is going to get very hot indeed. As I said above, the OP apparently indicates the axis of rotation is the same as it is now relative to the sun. ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [September 24, 2010, 11:58pm UTC](https://boards.straightdope.com/t/what-if-the-earth-was-rotated/554914/22 "2010-09-24T23:58:39Z")
> [@Colibri](#): > > > [@ZenBeam](#): > > > > At the new pole near Ghana, I’d expect ice will start forming on land from snow within a year, but the other pole is in the open ocean, so there may be enough currents to keep it ice free indefinitely. > > The actual pole off Africa as specified by the OP is hundreds of miles offshore, with free circulation of water from the new equatorial regions. Snow may fall around the Gulf of Guinea in the winter, but it’s unlikely that there would be enough net accumulation in the winter to result in an ice cap. (After all, most of the land above the Arctic Circle at present is ice-free during the summer.) The edge of the Ross ice shelf closest the South Pole is over 10 degrees from the pole, even though the water gets to within 5 degrees of the pole\*. Away from the coasts, isn’t the land of Antarctica covered in snow year round out to 20 degrees or so? The coast of Africa is only about 5 degrees away from the new pole. Draw a 20 degree radius circle, and it includes a big chunk of Africa. The OP asked about ice caps, not what happens exactly at the pole. I think you’d get year-round snow build-up on land quickly, with year-round ice off the coast eventually forming longer-term. \*precise measurements based on eyeballing my globe. ---
**Author:** ![Little\_Nemo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/little_nemo/32/3120_2.png) [@Little\_Nemo](https://boards.straightdope.com/u/Little_Nemo)\ **Post date:** [September 25, 2010, 1:17am UTC](https://boards.straightdope.com/t/what-if-the-earth-was-rotated/554914/23 "2010-09-25T01:17:54Z")
> [@Colibri](#): > > As I said above, the OP apparently indicates the axis of rotation is the same as it is now relative to the sun. Yes, that was my intent. ---
**Author:** ![Little\_Nemo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/little_nemo/32/3120_2.png) [@Little\_Nemo](https://boards.straightdope.com/u/Little_Nemo)\ **Post date:** [September 25, 2010, 1:19am UTC](https://boards.straightdope.com/t/what-if-the-earth-was-rotated/554914/24 "2010-09-25T01:19:41Z")
So the estimates range from ten years to never. These are just the kind of fuzzy predictions that are going to prompt the aliens to seek experimental results. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [September 25, 2010, 2:08am UTC](https://boards.straightdope.com/t/what-if-the-earth-was-rotated/554914/25 "2010-09-25T02:08:59Z")
> [@ZenBeam](#): > > The edge of the Ross ice shelf closest the South Pole is over 10 degrees from the pole, even though the water gets to within 5 degrees of the pole\*. Away from the coasts, isn’t the land of Antarctica covered in snow year round out to 20 degrees or so? The coast of Africa is only about 5 degrees away from the new pole. Draw a 20 degree radius circle, and it includes a big chunk of Africa. > > The OP asked about ice caps, not what happens exactly at the pole. I think you’d get year-round snow build-up on land quickly, with year-round ice off the coast eventually forming longer-term. As I have been trying to point out, the fact that there are ice caps on Antarctica and on Greenland and some of the other Arctic islands is very largely due to their topography, not how close the land is to the poles. There is an ice cap on Antarctica because the pole is surrounded by land, so that heat exchange via water is limited. Much of the ice around the circumference of the continent, including the ice shelves, is outflow via glaciers and ice sheets from the center of the continent. Likewise, the fact that ice caps developed in the north over the last few million years is due to the details of ocean circulation, especially the fact that the Arctic is a nearly enclosed basin. With a different kind of oceanic circulation, there would be no ice caps in the northern polar regions at all. The reason ice caps probably wouldn’t form on the coast of Africa, despite their proximity to the poles, is because there would be almost free circulation through the Atlantic Ocean, so that warmer water could circulate into polar regions. The new “polar” ocean in the Gulf of Guinea would be far warmer than the present Arctic Ocean is now, which would warm the adjacent coasts and prevent permanent ice from forming. If you place your new pole around an enclosed or semi-enclosed basin, however, such as the Mediterranean or the Gulf of Mexico, it would be quite possible that you would get ice caps forming. ---
**Author:** ![Little\_Nemo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/little_nemo/32/3120_2.png) [@Little\_Nemo](https://boards.straightdope.com/u/Little_Nemo)\ **Post date:** [September 25, 2010, 3:09am UTC](https://boards.straightdope.com/t/what-if-the-earth-was-rotated/554914/26 "2010-09-25T03:09:06Z")
> [@Colibri](#): > > As I have been trying to point out, the fact that there are ice caps on Antarctica and on Greenland and some of the other Arctic islands is very largely due to their topography, not how close the land is to the poles. There is an ice cap on Antarctica because the pole is surrounded by land, so that heat exchange via water is limited. Much of the ice around the circumference of the continent, including the ice shelves, is outflow via glaciers and ice sheets from the center of the continent. > > Likewise, the fact that ice caps developed in the north over the last few million years is due to the details of ocean circulation, especially the fact that the Arctic is a nearly enclosed basin. With a different kind of oceanic circulation, there would be no ice caps in the northern polar regions at all. > > The reason ice caps probably wouldn’t form on the coast of Africa, despite their proximity to the poles, is because there would be almost free circulation through the Atlantic Ocean, so that warmer water could circulate into polar regions. The new “polar” ocean in the Gulf of Guinea would be far warmer than the present Arctic Ocean is now, which would warm the adjacent coasts and prevent permanent ice from forming. > > If you place your new pole around an enclosed or semi-enclosed basin, however, such as the Mediterranean or the Gulf of Mexico, it would be quite possible that you would get ice caps forming. I guess I’m having a hard time seeing the reason for this. You have two different regions - one dry land surrounded by open water and one open water surrounded by dry land - but both have formed ice caps. So I assumed the common factor they shared - being located at a pole - was the cause of ice cap formation. If open water circulation prevents the formation of ice caps, why is Antartica frozen over? The water that surrounds Antartica are some of the fastest moving currents on Earth. I also thought that most currents were caused by planetary rotation and moved in an easternly or westernly direction for that reason. So I assumed that any polar region would be a “dead zone” where there would be minimal currents - the lack of rotation would mean no major currents would flow across a pole. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [September 25, 2010, 4:07am UTC](https://boards.straightdope.com/t/what-if-the-earth-was-rotated/554914/27 "2010-09-25T04:07:57Z")
> [@Little\_Nemo](#): > > I guess I’m having a hard time seeing the reason for this. You have two different regions - one dry land surrounded by open water and one open water surrounded by dry land - but both have formed ice caps. So I assumed the common factor they shared - being located at a pole - was the cause of ice cap formation. The common factor they share, besides being located at the pole, is that there is not free circulation of oceanic water to the region of the pole. The dry land around the South Pole extends for 20 degrees or so northward. Glaciation started in Antarctica about the time that the continent moved over the pole. The Arctic Ocean is not “open water.” It is an almost closed basin, and there is a fairly shallow sill across the widest connection with the Atlantic. There is not free circulation of warm water from other oceans into the basin. The reason for glaciation are more complex than that, but I’m not going to go into the details of the explanation here. > [@](#): > > If open water circulation prevents the formation of ice caps, why is Antartica frozen over? The water that surrounds Antartica are some of the fastest moving currents on Earth. The open ocean is very far from the center of the continent. As I mentioned, much of the ice around the periphery of the continent did not form there, but is outflow from the center of the continent which is isolated from the warming influence of the ocean currents. > [@](#): > > I also thought that most currents were caused by planetary rotation and moved in an easternly or westernly direction for that reason. So I assumed that any polar region would be a “dead zone” where there would be minimal currents - the lack of rotation would mean no major currents would flow across a pole. The global oceanic circulation is very complex. See this article on the global [thermohaline circulation](http://en.wikipedia.org/wiki/Ocean_conveyer_belt). While it might be difficult to predict exactly what would happen if one or both of the poles were in a open ocean basin exposed to free circulation, I would expect there would be much more heat exchange to the poles than there is now. (Note from the diagram that there is no thermohaline circulation into the Arctic Ocean - the basin is isolated from the global circulation). ---
**Author:** ![Sam\_Stone](https://avatars.discourse-cdn.com/v4/letter/s/ecccb3/32.png) [@Sam\_Stone](https://boards.straightdope.com/u/Sam_Stone)\ **Post date:** [September 25, 2010, 4:55am UTC](https://boards.straightdope.com/t/what-if-the-earth-was-rotated/554914/28 "2010-09-25T04:55:58Z")
As a guess, conservation of angular momentum means that changing the earth’s axis 90 degrees would require so much energy that it would reduce the earth into a glowing ball of slag. If it stayed together at all. ---
**Author:** ![md2000](https://avatars.discourse-cdn.com/v4/letter/m/73ab20/32.png) [@md2000](https://boards.straightdope.com/u/md2000)\ **Post date:** [September 25, 2010, 2:19pm UTC](https://boards.straightdope.com/t/what-if-the-earth-was-rotated/554914/29 "2010-09-25T14:19:02Z")
Here’s my wild-assed guess: the ice caps (except for glaciers at altitude) would be gone within a year. As someone who’s observed many annual freeze-thaw processes, it’s not so much the sunlight or ait temperature that matters - it’s precipitation. A deluge of water carries many more calories, and transfers them much faster, than warm air. A pile of snow will stay for quite a while, especially when it gets a nice insulating coating of all the accumulated debris - airborne dust in glaciers or road sand from ploughed streets. Water can seep past that protective layer and accelerate the melt. The arctic sea ice is realtively thin - the current global warming hue-and-cry points out that in recent years we’ve had open ocean at the north pole. I suspect it would not take more than a few weeks to do in that ice in tropical conditions. So that ocean would probably heat up pretty fast, and with corilis-induced “northeast” airflow, dump that rain on the Grennland ice cap. Ditto for the southern oceans onto Antarctica. We might see some massive glacial flow from the 15,000 foot mountains, but I bet anything under 10,000 feet would wash out to sea pretty quick. As for new ice caps - again,the gulf stream is a coriolis induced north-east flow from a warm shallow source in its simplest terms. The ice that forms around antarctica as mentioned above is due to lack of warm air/water circulation south of the coastline. Consider Iceland and Finland, both habitable agricultural countries well north of the southern edge of the Greenland ice sheet, but in the influence of the warm gulf stream flow. Alaska’s south coast has a much milder climate than more southerly areas of central Canada. Without a range of mountains to restrict warm air flow and impediments to ocean currents, I suspect the new poles would be realtively mild. In the age of the dinosaurs, the arctic was suffieicently mild that not-very-warm-blooded (?) dinosaurs migrated up and down the coast from Alaska to Mexico. This may have been helped by a shallow (warm?) ocean running up the east of the rockies and funneling all that warm gulf water into the arctic. ---
**Author:** ![MikeS](https://avatars.discourse-cdn.com/v4/letter/m/919ad9/32.png) [@MikeS](https://boards.straightdope.com/u/MikeS)\ **Post date:** [September 25, 2010, 2:45pm UTC](https://boards.straightdope.com/t/what-if-the-earth-was-rotated/554914/30 "2010-09-25T14:45:13Z")
Would the fact that there would be a great deal more land area in the tropics affect the climate of the new earth? The “new Equator” would be composed of what is now the 90th meridian West and the 90th meridian East. Most of North America, a good chunk of South America, and a vast swath of Asia (chunks of Siberia, Mongolia, Kazakhstan, China, India, and what is now SE Asia) would all be within 23° of this line. ---
**Author:** ![MikeS](https://avatars.discourse-cdn.com/v4/letter/m/919ad9/32.png) [@MikeS](https://boards.straightdope.com/u/MikeS)\ **Post date:** [September 25, 2010, 2:49pm UTC](https://boards.straightdope.com/t/what-if-the-earth-was-rotated/554914/31 "2010-09-25T14:49:56Z")
Oh, and if you want to see what the new world map would look like, go to [this site](http://www.btinternet.com/~se16/js/mapproj.htm) and select “North Pole” or “South Pole”. ---
**Author:** ![blue\_infinity](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/blue_infinity/32/2817_2.png) [@blue\_infinity](https://boards.straightdope.com/u/blue_infinity)\ **Post date:** [September 25, 2010, 2:52pm UTC](https://boards.straightdope.com/t/what-if-the-earth-was-rotated/554914/32 "2010-09-25T14:52:47Z")
> [@Colibri](#): > > You’ve also neglected to account for cloud cover. I suspect that that a large mass of ice in the tropics would cause condensation of warm moist air moving over it from the sea and be covered by clouds much of the time, limiting the effect of solar radiation. You don’t need direct sunlight to melt ice. Nighttime temperatures in the tropics can be 20+ degrees celcius. Ice cubes melt just fine indoors at room temperature. 10-20 years seems like a good guess to me. ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [September 25, 2010, 3:03pm UTC](https://boards.straightdope.com/t/what-if-the-earth-was-rotated/554914/33 "2010-09-25T15:03:40Z")
> [@Colibri](#): > > > [@ZenBeam](#): > > > > The edge of the Ross ice shelf closest the South Pole is over 10 degrees from the pole, even though the water gets to within 5 degrees of the pole\*. Away from the coasts, isn’t the land of Antarctica covered in snow year round out to 20 degrees or so? The coast of Africa is only about 5 degrees away from the new pole. Draw a 20 degree radius circle, and it includes a big chunk of Africa. > > > > The OP asked about ice caps, not what happens exactly at the pole. I think you’d get year-round snow build-up on land quickly, with year-round ice off the coast eventually forming longer-term. > > As I have been trying to point out, the fact that there are ice caps on Antarctica and on Greenland and some of the other Arctic islands is very largely due to their topography, not how close the land is to the poles. There is an ice cap on Antarctica because the pole is surrounded by land, so that heat exchange via water is limited. Much of the ice around the circumference of the continent, including the ice shelves, is outflow via glaciers and ice sheets from the center of the continent. > > Likewise, the fact that ice caps developed in the north over the last few million years is due to the details of ocean circulation, especially the fact that the Arctic is a nearly enclosed basin. With a different kind of oceanic circulation, there would be no ice caps in the northern polar regions at all. > > The reason ice caps probably wouldn’t form on the coast of Africa, despite their proximity to the poles, is because there would be almost free circulation through the Atlantic Ocean, so that warmer water could circulate into polar regions. The new “polar” ocean in the Gulf of Guinea would be far warmer than the present Arctic Ocean is now, which would warm the adjacent coasts and prevent permanent ice from forming. Africa is a large continent, over twice the area of Antarctica. How is warmth from ocean currents able to penetrate its interior when it doesn’t happen with Antarctica? There’s open water to Antarctica’s coast, but it’s still ice covered. Will the new South pole be warmer than than the coast of Antarctica? I don’t think it will. Why will there be more ocean heat warming Africa than Antarctica? Say specifically Niger, Mali, Burkina Faso? How? ---
**Author:** ![Little\_Nemo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/little_nemo/32/3120_2.png) [@Little\_Nemo](https://boards.straightdope.com/u/Little_Nemo)\ **Post date:** [September 25, 2010, 3:17pm UTC](https://boards.straightdope.com/t/what-if-the-earth-was-rotated/554914/34 "2010-09-25T15:17:05Z")
> [@Sam\_Stone](#): > > As a guess, conservation of angular momentum means that changing the earth’s axis 90 degrees would require so much energy that it would reduce the earth into a glowing ball of slag. If it stayed together at all. Alien space bats. ---
**Author:** ![md2000](https://avatars.discourse-cdn.com/v4/letter/m/73ab20/32.png) [@md2000](https://boards.straightdope.com/u/md2000)\ **Post date:** [September 25, 2010, 4:41pm UTC](https://boards.straightdope.com/t/what-if-the-earth-was-rotated/554914/35 "2010-09-25T16:41:22Z")
> [@ZenBeam](#): > > > [@Colibri](#): > > > > As I have been trying to point out, the fact that there are ice caps on Antarctica and on Greenland and some of the other Arctic islands is very largely due to their topography, not how close the land is to the poles. There is an ice cap on Antarctica because the pole is surrounded by land, so that heat exchange via water is limited. Much of the ice around the circumference of the continent, including the ice shelves, is outflow via glaciers and ice sheets from the center of the continent. > > > > Likewise, the fact that ice caps developed in the north over the last few million years is due to the details of ocean circulation, especially the fact that the Arctic is a nearly enclosed basin. With a different kind of oceanic circulation, there would be no ice caps in the northern polar regions at all. > > > > The reason ice caps probably wouldn’t form on the coast of Africa, despite their proximity to the poles, is because there would be almost free circulation through the Atlantic Ocean, so that warmer water could circulate into polar regions. The new “polar” ocean in the Gulf of Guinea would be far warmer than the present Arctic Ocean is now, which would warm the adjacent coasts and prevent permanent ice from forming. > > Africa is a large continent, over twice the area of Antarctica. How is warmth from ocean currents able to penetrate its interior when it doesn’t happen with Antarctica? There’s open water to Antarctica’s coast, but it’s still ice covered. Will the new South pole be warmer than than the coast of Antarctica? I don’t think it will. Why will there be more ocean heat warming Africa than Antarctica? Say specifically Niger, Mali, Burkina Faso? How? OTOH, northern Canada and Siberia do not have permanent ice sheets covering them. The seasonal changes mean that depending on moisture a bit to a LOT of snow falls in the winter, and the warm air and sunshine melts it in the spring. The only place that seems to get a permanent ice cap is Greenland, where North America blocks the warmer moist air flow and the surround water is mostly ice-covered. In our hypothetical bat-world, the arctic ocean off Ghana should be fed by a wide-open stream from the sub-tropical regions. We might expect serious snow in the winter, but I bet no ice sheet accumulations. Of course, that depends on what the resultant coriolis-induced new ocean currents are. The antarctic is frozen because the ocean currents stop at the edge of the continent, and it is centered on the pole. I wonder what it would be like if it the pole was in open water a few hundered miles off the coast? Much milder, I suspect. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [September 25, 2010, 5:04pm UTC](https://boards.straightdope.com/t/what-if-the-earth-was-rotated/554914/36 "2010-09-25T17:04:43Z")
> [@ZenBeam](#): > > Africa is a large continent, over twice the area of Antarctica. How is warmth from ocean currents able to penetrate its interior when it doesn’t happen with Antarctica? There’s open water to Antarctica’s coast, but it’s still ice covered. Will the new South pole be warmer than than the coast of Antarctica? I don’t think it will. Why will there be more ocean heat warming Africa than Antarctica? Say specifically Niger, Mali, Burkina Faso? How? Because the new pole would not be in the “interior of Africa,” but well offshore. If the new pole were in fact located in the interior of Africa, I would agree that an ice cap would form there. I’ve already explained several times that the ice on Antarctica’s coast does not for the most part originate there, but rather in the interior of the continent, and then flows outward. If the diameter of the continent were smaller, there might not be an ice cap there. Look at the map. In the south, virtually all land south of the Antarctic Circle is under an ice cap. In the north, huge areas of land north of the Arctic Circle, including parts of Siberia, Canada, Alaska, and Scandinavia, are not glaciated. The difference is because the South Pole is in the center of the continent, and the North Pole is not. (Of course, this dynamic changes depending on which part of the glacial/interglacial cycle we are. In other parts of the Milankovich cycle, ice caps have formed in the north.) Formation of ice caps requires some very particular conditions of continental positioning and oceanic circulation. It is far from deterministic, and can’t be predicted simply from distance of a land mass from the pole. As has been said, the actual outcome is largely unpredictable, and it is possible that an ice cap would form on the coast of Africa if the pole was in the Gulf of Guinea. However, my best guess based on probable oceanic circulation patterns is that a large one would not form, although there likely would be glaciation around Mt. Cameroon. ---
**Author:** ![Erdosain](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/erdosain/32/7284_2.png) [@Erdosain](https://boards.straightdope.com/u/Erdosain)\ **Post date:** [September 25, 2010, 6:15pm UTC](https://boards.straightdope.com/t/what-if-the-earth-was-rotated/554914/37 "2010-09-25T18:15:29Z")
So what would happen if we had a Uranus-type axis? Would the oceans boil away with some ice trapped on the other side of the globe? Or would we lose all water? ---
**Author:** ![MikeS](https://avatars.discourse-cdn.com/v4/letter/m/919ad9/32.png) [@MikeS](https://boards.straightdope.com/u/MikeS)\ **Post date:** [September 25, 2010, 6:42pm UTC](https://boards.straightdope.com/t/what-if-the-earth-was-rotated/554914/38 "2010-09-25T18:42:39Z")
> [@Erdosain](#): > > So what would happen if we had a Uranus-type axis? Would the oceans boil away with some ice trapped on the other side of the globe? Or would we lose all water? It might not get quite hot enough for the oceans to boil, but it’d definitely be mighty uncomfortable. If the Earth were tidally locked with the Sun, so that one side always faced the Sun, you can use the laws to physics to estimate that the temperature on the sunward side of the planet would be about 19% higher in degrees Kelvin. (For the boffins in the audience, use the Stefan-Boltzmann law to balance energy in w/ energy out, and assume that the Earth only radiates over half of its surface rather than all. It works out to an increase in T by a factor of 2[sup]1/4[/sup].) This corresponds to an increase in average temperature from 20 C to a balmy 75 C. Higher temperature would mean additional water vapour in the atmosphere, which could act as a greenhouse gas but would also lead to more clouds, so it’s hard to say which way (hotter or cooler) that would push this estimate. Still, it’s hard to see how you would make up the extra 25 C or so needed to boil the oceans. The above assumes that the Earth always has one side towards the sun. As noted above, though, a Uranus-style rotation axis would mean that most points on the Earth would get six months of non-stop sun and six months of darkness instead. I don’t know enough about meteorology and climate science to speculate on what the climate of such a planet would be like, other than to say that (a) the high temperatures probably wouldn’t be significantly higher than the 75 C estimate above, and (b) there would be some pretty wicked weather patterns along the terminator. ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [September 26, 2010, 1:00am UTC](https://boards.straightdope.com/t/what-if-the-earth-was-rotated/554914/39 "2010-09-26T01:00:02Z")
> [@Colibri](#): > > > [@ZenBeam](#): > > > > Africa is a large continent, over twice the area of Antarctica. How is warmth from ocean currents able to penetrate its interior when it doesn’t happen with Antarctica? There’s open water to Antarctica’s coast, but it’s still ice covered. Will the new South pole be warmer than than the coast of Antarctica? I don’t think it will. Why will there be more ocean heat warming Africa than Antarctica? Say specifically Niger, Mali, Burkina Faso? How? > > Because the new pole would not be in the “interior of Africa,” but well offshore. If the new pole were in fact located in the interior of Africa, I would agree that an ice cap would form there. I don’t understand what question you’re trying to answer here. This doesn’t seem to answer any of the ones in the quote. I’ll just respond that I don’t think there’s some kind of sharp cutoff between whether the pole is on shore or off-shore. > [@](#): > > I’ve already explained several times that the ice on Antarctica’s coast does not for the most part originate there, but rather in the interior of the continent, and then flows outward. If the diameter of the continent were smaller, there might not be an ice cap there. The accumulation due to snow fall is roughly uniform through the interior, and with much more near the coasts. It doesn’t just fall at the pole. Based on Figure 2 [here](http://www.sciencemag.org/cgi/content/abstract/313/5788/827), although you have to register (free) to see it. > [@](#): > > Look at the map. In the south, virtually all land south of the Antarctic Circle is under an ice cap. In the north, huge areas of land north of the Arctic Circle, including parts of Siberia, Canada, Alaska, and Scandinavia, are not glaciated. The difference is because the South Pole is in the center of the continent, and the North Pole is not. All those coasts are 15 - 20 degrees from the pole. Greenland is a comparable 5 degrees from the pole, but it has an ice cap. ---
**Author:** ![dracoi](https://avatars.discourse-cdn.com/v4/letter/d/90db22/32.png) [@dracoi](https://boards.straightdope.com/u/dracoi)\ **Post date:** [September 26, 2010, 1:10am UTC](https://boards.straightdope.com/t/what-if-the-earth-was-rotated/554914/40 "2010-09-26T01:10:15Z")
> [@blue\_infinity](#): > > > [@Colibri](#): > > > > You’ve also neglected to account for cloud cover. I suspect that that a large mass of ice in the tropics would cause condensation of warm moist air moving over it from the sea and be covered by clouds much of the time, limiting the effect of solar radiation. > > You don’t need direct sunlight to melt ice. Nighttime temperatures in the tropics can be 20+ degrees celcius. Ice cubes melt just fine indoors at room temperature. > > 10-20 years seems like a good guess to me. But those nighttime temperatures are based on sun during the day. You’re also overlooking elevation. Antarctica is pretty mountainous. It is not 20+ C at night at 15,000 feet, even during summer in the tropics. [Previous page](https://boards.straightdope.com/t/what-if-the-earth-was-rotated/554914.md?page=1)