Why does Antarctica Have More Ice Then the Arctic?

The Earth's tilt (more like 23.45 degrees) has nothing to do with one pole getting more sunlight than the other. The reality is that both poles get the same amount of sunlight over the course of a year. No matter where the Earth is in its orbit, an imaginary line extending from the North Pole to the North Star (Polaris) always points to the North Star, no matter what (purists may be tempted to point out here that this imaginary line doesn't exactly lead to the North Star, but to a point nearby, and it is true. It is also completely irrelevant for the purposes of this discussion).

Say at December 21 the Earth is at some point X in its orbit. Antarctica is basking in sunlight and, for points south of the Antarctic Circle, the sun doesn't even bother to set. Meanwhile, the Arctic is bathed in total darkness and, for points north of the Arctic Circle, the sun doesn't even bother to rise.

Now it's June 21, half a year later, and the Earth is at a point Y in its orbit; a point 180 degrees away from its January position. Now simply substitute Arctic for Antarctic in the paragraph above, and you've got the whole picture of what it's like for both poles six days before my birthday.

The tilt of Earth's axis with respect to Earth's orbital plane has nothing at all to do with the sunlight received over the course of the year. Any tilt, no matter what the value - including no tilt at all - would not change a thing, so there must be other factors at play.

For one thing, Antarctica is a continent; a land mass with plains, mountains, and valleys. The Arctic, however, is not. There's no land under all that ice. Just water.

If Earth's surface were completely symmetric in every way, both poles would have nearly identical ice coverage. The problem is one of continent-scale topography, not of relative sunlight received.

-E

There must be land under the ice. Water doesnt float in thin air..

As Europium stated, both poles get the same solar radiation. I don't know what the estimated polar ice mass is for each pole, but the North Pole is pretty much floating ice, whereas the South Pole is an actual land mass covered with ice. I would suspect that is the reason for any different amount of ice. However, you also need to look at winds such as the Jet Stream and ocean currents, which may be a large factor.

Absolutely! Topography is only one factor, and I should have mentioned ocean currents and climatic considerations, as well. The main point, however, was to address the poster's assertion that the poles experience different amounts of sunlight, which is simply not true.

-E

I think the guest is quite right.

Just assume a case if axis of earth is tilted by 90 Deg. insteed of 23 DEG

On the same orbit.

Now arctic will never face sun. means no daylight. where as antactica will never have night.

There are a great many websites (and libraries, and universities, and grade schools) where you can verify that Europium's explanation is correct. The fact that both the northern and southern hemispheres experience winter and summer should also make you suspect that your belief is incorrect. Is there a new belief system that promotes a different of the solar system?

Both the things are diffrent.

tilting is fix and never change accross the years.

so long it is the question of experienceing winter and summer in northern and southern hemispheres is due to the fact

plan of orbit is not parallal to paln of equator.

just consider a cylender truncate it a an angle that can create an orbit.

just put our sun at the focus of orbit.

revolution axis of earth is parallel to axis of cylender.

where as orbit parth is the truncated ellipes.

Now every year sun will move from north to south from and then south to notrth.

from line of capricon to line of cancer.

Just think a loud.

I'm not sure what you are suggesting here, but if it is that one pole faces the sun all the time, that is utterly and totally incorrect. If you believe that, then you have a total misunderstanding of the cause of our seasons. Changing the amount of tilt from 23.45 to 30 to 35 to 60, and so forth, makes no difference in the basic concept: in December the southern pole points generally toward the sun; in June, the northern pole points generally toward the sun.

If you looked at our solar system "from the side" the angle of tilt would appear constant: lets' call it up and to the right. The axis would appear to point up and to the right in June (and Earth would be toward the left side in our mind's picture) and up and to the right in December. Therefore, in June, the sun aims most directly at the northern hemisphere, and in December it aims most directly at the southern.

If you are proposing that one pole faces the sun all the time, you are arguing against everything considered well-know by scientists (and the majority of grade school students) for many centuries. If you are seriously arguing that, then I think that this discussion might better fit in a religion or philosophy forum (although I can think of no religion or philosophy that supports that contention, either).

No as mentioned by an earlier contributor, the earth's orbit is not circular, and summer for the southern hemisphere happens to be closer to the sun while winter is further away.

Actually, I was responding to post 13, which (I think) was supporting post 7, contrary to Europium's correct explanation of the basic cause of seasons. (It's rather hard to tell which guest is which – but there appear to at least two who are suggesting that one pole is always tilted toward the sun.) Might you have your browser set to chrono rather than threaded?

Thank you for getting me back on track. Yes, I agree that north pole is pointed toward the north star so the orbit of the earth causes the seasons.

David

Rubbish!

If the axis-to-orbit tilt was 90 each pole would have 3 month long days (and bl00dy cold 3 month long nights) with a transition period bewteen of 3 months each, where the days would get longer/shorter:

Permanent day - days get shorter - permanent night - days get longer....repeat. So more of what they get at the moment. The major change would be experienced at the Equator, which would have seasons (currently have negiligible change throughout the year at the current tilt) and the same Permanent day - days get shorter - permanent night - days get longer cycle as the poles.

This is because the "south" pole does not always point at the sun - It always points in the same direction in a frame of reference outside the solar system which means if it points at the sun in December, it points away from the sun in June. Think of the earth as a particle in a non-rotating circular flow (as opposed to a rotating circular flow). I'd draw a picture, but I'm not sure this site has in-post graphics?

Do I have to mention that the Northern hemisphere will be 1/2cycle different from Southern?

Rubbish? In this discussion everyone is entitled to be wrong. Including ... in this case...Rose. The problem with all these speculations is that they demonstrate nothing, except a propensity for argumentativeness.

Because the earth and the sun are closer during the summer of the southern hemisphere then the southern hemisphere gets more sunlight than the northern hemisphere.

David

David think of it like this. Seasons are caused by Earth's tilt from perpendicular to the ecliptic--in which the orientation of its axis to the sun's axis changes continuously. The seasonal weather extremes are mitigated by Earth's position in its orbit--its distance from the sun--at the time of the summer (when at apogee) and winter (when at perigee) solstices. Which means it does not (on average) get quite as cold in winter as it otherwise would (in the northern hemisphere), or as hot in summer as it otherwise would (in the northern hemisphere).

Europium

Earth is always tilted outward with respect to south pole on its orbit. no matter what date of year.

It is the elliptical nature of orbite that causes climatical chage.

I too blv that both the pole experienced diff ammount of sunligts.

You wrote: "Earth is always tilted outward with respect to south pole on its orbit. no matter what date of year. It is the elliptical nature of orbite that causes climatical chage."

Sorry. Wrong on both counts.

-E

Earth's axis is not always tilted outward, if it were, the Northern hemisphere would never experience winter and visa versa. The eliptical orbit has some affect, but not as much as the fact that the axis always points in the same direction and causes differences in both amount of sunlight and the intensity due to angle changes. The fact the Antartica is a land mass with heating and cooling cycles associated with soil is the reason there is more ice. The Arctic being only ice has a finite limit on its thickness (you can only add so much ice to existing ice without any melting cycles). Besides, Antartica is many times larger than the Arctic so total ice would be greater when speaking only of mass and not depth. Antarctica also experiences colder temperatures and more fluctuating levels.

Antarctica is also the driest place on Earth. The Sahara Desert is a tropical paradise by comparison.

-E

Yep.

One bit of evidence (that anyone can easily verify for him/herself) that totally scraps the "pole outward" theory is the embarassing fact of the North Star's apparently fixed position in the sky. If the poster's "outward" theory were actually the case, the North Star would appear in its actual location only once per year (not to mention rendering every star map ever printed totally worthless).

-E

Sorry, but the tilt of the earth is toward the north star so the earth's rotation causes the seasons due to the north or south being more in the sun. Separately the earth's orbit is an elipse which causes the south to get more sunlight. However, the climates are very similar for the same latitude due to the mitigating effect of the predominance of water in the southern hemisphere.

David

Sorry-er yet, but the northern aspect of Earth does not tilt toward (does not track) the north star. (However, the earlier reference to it to rebut the "annual precession" theory (belief) was quite splended.) That star's alignment over the north pole is a matter of apparency only due to its great distance. Polaris has not always been the "north" star and, given passage of enough time, another star (if visible) will take its place. The "recent" history and future predictions of "north" stars has been determined and documented...in case one wishes to look it up.

Hasn't anyone figured out, yet, that the original post-er's seemingly naive question was quite probably meant only to pull our chains? Or perhaps that post-er was a child, in which case he/she must be utterly confused by now.

You are correct about the north pole only apparently tracking polaris.

David

As stated the North Pole is floating ice that is constantly forming and breaking off to drift with the currents. Early North Pole explorers would beach their ships in the ice and travel with the current across the pole. The ice is all broken up, upended and difficult to traverse on foot.

Ask a silly question, get a silly answer...

Because the more white ice there is to reflect back the sunlight, the less the sunlight can heat and melt the ice.

Now please go back and rephrase your question-and include the dozens of other questions subsumed by your question. Also, please define what would constitute "Artica"--so we would be comparing like with like. And what exactly you mean by "ice"? Also include whether or not you refer to fresh water ice, or salt water ice. You will perhaps come to recognize that knowing the right questions is more informative than getting the right answer--or should I say answers, many many answers.

The earth's orbit is not a perfect circle. Our planets closest approach to the sun (perihelion) occurs on January 4th 2007, in the middle of the southern summer. The earth sun distance is then about 3% less than on July 4th when the earth is furthest from the sun (aphelion). The total solar radiation falling on the earth is about 7% more at perihelion than at aphelion - in theory making southern winters colder ans summers hotter than northern ones. The reason they aren't is that there is far more ocean in southern hemisphere, which is another reason for the greater snowfalll and accumulation in the Antarctic. Not all of the Antarctic is desert, and anyway, the higher elevation of the Antarctic make evaporation much less than in the Arctic - so the net precipitation is higher.

I agree with everything you stated except about evaporation which occurs at a lower temperature at higher elevations. Also, the reason for the lower average temperatures in the southern arctic is also the higher elevation.

As the Antarctic is a continent, there are no currants to warm the central mass of ice, enabling it to build up a mile thick ice sheet. Think of a huge heat sink.

Look at how the ice sheet surrounding the continent doubles the size of the continent in winter.

I think PLBMAK is on to something. There is more landmass in the Northern Hemisphere. I would guess it absorbs more heat during the Northern Hemisphere summer and then releases that heat during the Northern Hemisphere winter.

Whereas the Southern Hemisphere heat during the summer is partly abosorbed by the oceans, but more of it is refelcted back to the atmosphere because land absorbs heat more readily than water.

That is a Civil Engineer's guess.

Btw, why are you guys called 'Civil' Engineers? My experiences have been somewhat different.

-E

How dare you sir! I'm never civil about anything!

Water absorbs more heat than land. That is the reason the southern hemisphere has about the same climate as the northern hemisphere at the same latitude even though the southern hemisphere is closer to the sun in the summer and further away in the winter because there is more water in the southern hemisphere. As I stated earlier, the average altitude of the southern arctic is the reason it is colder than the northern arctic.

David

Antartica: 10,000+ elevation of the central portion / surrounded by oceans - no nearby major land masses / ocean currents that circle Antartica

Artic: low elevation of majority of surounding land masses, (Greenland is a Major exception even though it's on the edge of the Artic) / Ocean current (example-Aritc conveyer) carry heat into the Artic and cold waters out of it. / Major amounts of polution is deposited on the surface of the ice increasing absorption of heat (China is probably the largest source of particulate materical)

Human activity probably does affect the northern arctic somewhat; however, you might want to look at the websites below that discuss some of the issues about global weather cycles that appear to mimic what happened just prior to the the last Mini-Ice-Age when Viking Explorers settled Iceland, Greenland (which they eventually abandoned during the Mini-Ice-Age), found grapes growing in Canada in an area that they called Vinland (their settlements there have now been found by archeologists even though it was earlier thought to be a TALL TALE - Myth) AND vineyards grew in England like they now do in France. There was a very warm period during the Middle Ages followed by the last Mini-Ice-Age (1150 to 1460) and there was more recently a Little-Ice-Age (1645-1705). There are numerous climate experts predicting a coming Mini-Ice-Age based on the changing water flows in the North Atlantic. Also, there is a Russian Astronomer predicting another Little-Ice-Age during 2035-2045 due to predicted reduced solar output as part of the Sun's cycles. Also, there is global warming on Mars. Therefore, it is not clear that human activity is the cause of the current warming cycle and we may actually have very limited ability to change the large climate cycles due to solar output, ocean currents, and other things out of our control at this stage of our technological development.

http://www.nasa.gov/vision/universe/solarsystem/mgs-092005-imagesc.html

http://en.rian.ru/russia/20060206/43371626.html
http://www2.sunysuffolk.edu/mandias/lia/little_ice_age.html
http://www.stanford.edu/~moore/history_health.html

http://news.nationalgeographic.com/news/2005/11/1130_051130_ice_age_2.html
http://www.newscientist.com/article.ns?id=dn8398

http://www.citizenreviewonline.org/dec2005/11/warming.htm

OMG. I'm glad that all the chickens (guests) have gone from this thread. I was starting to get worried about some people's basic schooling if they thought that the axis of the Earth was constantly moving with the seasons ( it does move slightly).. Were they thinking of the magnetic poles or this might totally confuse them He..He.

Ha Ha just had a throught. Do they know that it can totally reverse (flip) so North is South and South is North.

But this is another thread

Naturally, the only chicken that could be on a single-post "thread" (which in this case is now an actual thread) would be on a chicken-posted thread. Sorry, just couldn't resist the temptation you offered. But some might say that a Chicken would be a bloke (educated or uneducated) with the extra time and natural inclination to peck around trying log on, in order to crow about his superiority...whereas a guest might merely be one, perhaps even not so well educated--but certainly more cultivated--who seeks no more than to avoid personalizing efforts to correct the sometimes preposterous errors made by Avatars. See, matey?

Sorry,

I was having a bad morning. Didn't mean to be facetious (yes i had to look up the correct spelling). Superiority? I wish. I get your point. No one likes a smart aleck but it's hard to read somebody's message when they try to correct you ( or somebody that obviously knows what they are writing about) about basic (yes, grade 6 basic) knowledge. And they think they are correcting you but can't even bother to spell check ie.#4.

Ooop's. I am doing it again. Now i'm having a bad afternoon.

I might just go lie down for a while. And when I wake up all this might of been just a horrible nightmare.

It look like that there is one guest and making chicken of all.

No, just trying to make mirth for our great friend (yaar/saarthi/baba) from Perth.

Nothing to do with the 23 Deg

I think the reason is just because antartica is a continent and the artic is only ice, the ocean currents brings warm water to the artic but in the antartic the ocean currents can not reach the inland ice

Ciro

What a talent we all have for being distracted. I think the question was why the arctic ice is thinner than the antarctic ice. The main factor is insulation, though salt may also contribute. The antarctic ice sits on a stationary mass of solid land. So any heating of its undeside relies on thermal conduction. The arctic ice is floating, and the water underneath it is not stationary (you could look up look gulf stream, atlantic conveyor ...). So the temperature at the base of the ice at the arctic is maintained at a higher temperature than that at the Antarctic. The ice will melt at the base of the pack whenever the pressure (due to the weight of ice above it) raises its melting point to the temperature of the ambient. In the case of the Arctic ice, this is the temperature of the seawater (the fact that the water is salty also raises the melting temperature - but I'm not certain how significant this is in the scheme of things). In principle the Antarctic ice could be molten at the bottom, but the latent heat of melting will need to be replaced, so the rate of melting would be limited - although there is a contribution from the depth of the ice itself (as the ice melts at the bottom , the pack will fall, releasing gravitational energy - and, yes, that is an oversimplified description). However, it could well be that solid flow of the antarctic ice means that the base does not in fact melt - does anyone know what is the actual situation?

Why does Bill Gates have more money than Warren Buffet?

Now that's a question. I think the answer is it was never Warren Buffet's desire to be the richest man on the planet. He just likes running businesses well. My car insurance is Geico, which is owned by Warren Buffet, and it is by far my favorite company to deal with. I wish he would buy Time Warner Cable or National Grid. If Warren Buffet wanted to be the richest man on the planet in two years, I'm pretty sure he could. (Sorry if I messed up your joke, I just love the guy)

I think this is a US region conversation, 'cos I dont know who Warren Buffet is.

Yes, this is definitely a US region thing. Warren Buffet is the personification of the American dream. He was born during the great depression, and through hard work, shrewed investing, and a strong constitution to resist the fads and trends that sink most investors and businesses, he became the second richest person in the world. His company, Berkshire Hathaway, has billions in profits every year. The thing about Buffet is he believes the best businesses try to serve the customer, not exploit them, and he uses his approach in all of his businesses (Berkshire Hathaway has many businesses under it's umbrella). Also, He's a throwback to a better time for American businesses. He's also very liberal. I stop what I'm doing and watch whenever I see him on TV talking, which is rare since the man isn't really interested in that fame foolishness. When he dies he's giving almost all his money to charity.

http://en.wikipedia.org/wiki/Warren_Buffett

I have thought about this since gloable warming became an issue. Common sense has also taught me that like a chimney effect hot air will go up and in this case I am assuming up will be north. Funny to think of the noth pole as up but the facts seem to bear this out. I have often worndered if the holes in the upper atmosphere made by rockets are ever really sealed naturally or is that natural sealing ability comprised by the number of rocekt launches and the different gasses from so many types of rocket fuels. At what point will the forces at that level be comprimised to the point of no return.

Holes in the atmosphere made by rockets? Are you referring to ozone holes...predominately over the southern polar region? Please clarify.

The Earth's tilt (more like 23.45 degrees) has nothing to do with one pole getting more sunlight than the other. The reality is that both poles get the same amount of sunlight over the course of a year. No matter where the Earth is in its orbit, an imaginary line extending from the North Pole to the North Star (Polaris) always points to the North Star, no matter what (purists may be tempted to point out here that this imaginary line doesn't exactly lead to the North Star, but to a point nearby, and it is true. It is also completely irrelevant for the purposes of this discussion).

Brilliant.