Naked Science Forum
Life Sciences => The Environment => Topic started by: neilep on 19/09/2009 12:13:48
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Dearest Peeps of Incredible High Score Achievements In Exams & Stuff !
As a sheepy I of course have travelled the world...from swimming in the Dead Sea to climbing atop Everest..I have even ventured into space where I made friends with a species of sheep that graze the fields of Mars ! [ Invalid Attachment ]
I've yet to venture the farthest North or South though here on Earth to the poles. The North & South poles are my all time favourite most northern and southern parts of this planet !
Lookey here:
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South Pole..It's South Ewe Know ?
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North Pole...it's Not South.
As ewe can see, they both look so inviting and welcoming.
But, is there a difference in temperature between the two or are they about the same ?...if so...why so ?
It's important for me to know because I need to know whether to pack an extra pair of thermals or not !
Hugs and shmishes
mwah mwah mwah !
Neil
If I ever get the chance
At the poles I'd like to dance
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I think ewe may have got those pictures of the South and North poles the wrong way around.
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OOOOOH with that Bum of yours you would be a great pole dancer!!
This is what I have found...so far in looking!
http://www.madsci.org/posts/archives/2005-06/1118131199.Es.r.html
Date: Mon Jun 6 14:40:26 2005
Posted By: Ken Harding, Science and Operations Officer, National Weather Service
Area of science: Earth Sciences
ID: 1117827553.Es Message:
Many factors affect temperatures on the earth. Some of the most important are: location, nearness to oceans, land cover, and weather patterns. I’ll speak to the extreme cold at the South Pole, but most of the arguments hold for the North Pole as well.
Location: Over one year, every point on earth gets the same amount of daylight. Based on your location, it changes with the seasons. In the tropics, the day length doesn’t change very much from summer to winter. For example, at Christmas Island in the Pacific Ocean (only about 1.5 degrees north of the Equator), the longest day of the year is June 15 with a sunrise of 5:53 AM and sunset at 6:08 PM. The shortest day of the year is January 2 with a sunrise at 6:04 AM and a sunset at 6:04 PM – only 15 minutes difference between the longest and shortest day of the year. Thus, this area receives nearly constant sunshine…no great differences in day length to allow great temperature swings.
At the exact South Pole, the sun rises on March 21, and sets on Sep 21. Only one ‘day’ per year, with day and night each lasting 6 months. Thus, when it’s dark for so long, it can get very cold. (Source : http://www.usno.navy.mil/
Solar path of sunlight Another factor of location is called solar path length. The sunlight that shines on the equator shines nearly straight down, while the sunlight that shines on the South Pole has to go through relatively more atmosphere, which filters out more of the energy.
Nearness to oceans: Generally, oceans act to prevent big swings in temperatures. For example, Seattle Washington is about as far north of the equator as Grand Forks, North Dakota. The average low temperature in January in Seattle is 34 degrees, while in Grand Forks, the average low in January is 4 below zero. Most of this difference is due to the Pacific Ocean providing relatively warm water to keep Seattle warm. At the South Pole, the ocean is very far away, so there is no relatively ‘warm’ water to keep temperatures from falling.
Land cover: The nature of the land’s surface affects how much of the sun’s energy gets absorbed (making it warm) or reflected (which keeps it from being warm). If the ground id dirt, water, trees, cities, etc., then plenty of solar energy is absorbed. At the South Pole, the snow and ice reflect nearly 100% of all the sun’s energy back into space. Thus, when the sun does shine, it doesn’t warm up anything, and it keeps getting colder.
The following figure shows the net solar radiation received across the earth in January. This is the sum of sunlight in minus heat out. Notice the South Pole has a net value around zero which means no net warming by the sun. This is in the middle of summer! In the winter, the sun doesn’t shine, so the net is negative, and it just gets colder.
Finally, weather patterns affect extreme temperatures. Weather patterns are somewhat dependant on the above factors. Very cloudy places tend to be warmer in the winter as the clouds act like a blanket to keep heat close to the ground. At the South Pole, clouds actually increase the temperature. However, the atmosphere is so cold, and dry, that there are often not many clouds, and it stays very cold.
The coldest temperature ever recorded on the earth’s surface was at Vostok, Antarctica in August 1960, with a reading of -129 degrees Fahrenheit!
Here are some other web links that contain good information about the earth’s energy budget and how it affects temperature: http://www.uwsp.edu/geo/faculty/ritter/geog101/textbook/energy/outline.html
http://cimss.ssec.wisc.edu/wxwise/homerbe.html
Ken Harding
National Weather Service
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I think ewe may have got those pictures of the South and North poles the wrong way around.
CORRECT !!!
Ewe are VERY klevur !!...Ewe spotted my deliberate mistake !!
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OOOOOH with that Bum of yours you would be a great pole dancer!!
This is what I have found...so far in looking!
http://www.madsci.org/posts/archives/2005-06/1118131199.Es.r.html
Many factors affect temperatures on the earth. Some of the most important are: location, nearness to oceans, land cover, and weather patterns. I’ll speak to the extreme cold at the South Pole, but most of the arguments hold for the North Pole as well.
Thanks for the great info Karen....In the above it seems to suggest that perhaps the South Pole is colder than the north !
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Aww, it wasn't really all that klevur. Let's see if anyone else can figure it out (I'll just point out that I didn't spot it because I recognised the South Pole base - you can deduce that the pictures are the wrong way around).
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I was reading in one article that there was thought to be about a ten degree difference but I do not know what time of year that would be or if they were comparing them in each ones winter or what!
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Historically the Northern and Southern hemispheres exhibit an anti-correlation in temperature. This is at least partly due to the Atlantic's South Equatorial Current. The SEC is one of the only main surface currents that crosses from South to North, and is originally part of the South Atlantic Sub-tropical Gyre. Most of the warm waters of the SEC are redistributed into the Gulf of Mexico through the Yucatan Current and eventually into the Gulf Stream. A large portion of heat transported by the SEC never makes it back to the high latitude Southern Hemisphere, and instead warms the cozy buns of Candians, Americans, and Europeans :) That is at least one mechanism that keeps the NH warmer than the SH during periods of high Gulf Stream transport.
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Aww, it wasn't really all that klevur. Let's see if anyone else can figure it out (I'll just point out that I didn't spot it because I recognised the South Pole base - you can deduce that the pictures are the wrong way around).
Spill the beans LeeE. Great observation !
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I’ll take a guess and say that the North Pole is warmer than the South Pole but, by how much, I don’t know.
Even though both “poles” sit upon ice and snow at the most extreme latitudes on Earth (ie, 90°), because the NP sits over water and the SP sits over land (Antarctica), the NP is warmer that the SP because the water under the NP acts as a thermal mass that can only drop to a minimum temperature (approx 0 °C) whereas the Antarctic continent under the SP has the potential of dropping much lower.
Also too, everyone knows that the higher up one goes, the cooler the temperature. So, the NP, just several feet above sea level, should be warmer that the SP which, being over a continent, probably has some altitude to it, unless it sits cozily in some sort of “Grand Canyon of Antarctica” – but I’ve never heard of such thing.
Cloud cover makes a difference too. A region enshrouded in clouds will retain heat because the clouds act as blankets – that is, the clouds prevent some of the heat from escaping into space and reflects some of that heat back to the planet’s surface. Amazingly, ancient Egyptians had an ice-making process that (ideally) involved putting water in shallow porous bowls set on roofs on cloudless nights. The dampness would partly evaporate from the underside of the bowls, thus drawing off heat, the winds would also assist in drawing heat away, and the cloudless sky would allow the heat of the water in the bowls to radiate into space. The Egyptians would wake in the morning to find the bowls covered with a crust of ice. Cool!
Ozone covers the Earth, but a difference between the NP and SP involves the SP having a “hole” in the ozone layer over it. Some folks used to scream about this years ago, but I haven’t heard anything lately, so maybe it no longer exists. If this “hole” continues to exist, it may cause the Sun’s radiation to affect the SP differently than the NP.
Fascinating read and very interesting too. Particularly interested in the Egyptian method of free ice !
Thank ewe DiscoverDave for your very informative post. It all seems completely logical.
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I was reading in one article that there was thought to be about a ten degree difference but I do not know what time of year that would be or if they were comparing them in each ones winter or what!
Thanks Karen...well, that was an informative article ewe read ! [;D]...but at least it did confirm a substantial temperature difference.
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From NASA (http://www.gsfc.nasa.gov/scienceques2005/20060310.htm):
... how do [the poles’] temperature regimes compare? In a nutshell, the South Pole is colder, a lot colder. Basically, it’s colder not only because it’s more than 9,000 feet (2,743 m) higher but also because it has a higher continentality than its northern counterpart.
Continentality is the measure to which a spot on the Earth’s surface if influenced by a landmass. It’s partially based on the distance to the sea or other large moisture source. Theoretically, the coldest minimum temperature should occur where the continentalty is highest. The area around the North Pole consists of ice flows, which are commonly about 10 ft (3m) thick, beneath which lies relatively warm seawater (~28 °F or –2°C). Since the South Pole is near the center of Antarctica, a landmass 1.7 times larger than Australia, and since the North Pole is in an ocean, albeit a frozen one, it’s pretty obvious which one has a higher continentality.
... At the South Pole (Amundsen-Scott Station), the average temperature of the coldest month (August) is approximately –76 °F (–60 °C), and the average temperature of the warmest month (January) is – 18 ºF (–28.2 °C). Records go back at the South Pole to 1957. At the North Pole, long term temperature records aren’t available, but in 2003 a live weather camera and an unmanned weather station were installed on the sea ice. During the last 3 years, the daily temperatures have vacillated between about –40 ºF (–40 ºC) during December and January to a little above freezing (0 ºC) in June, July and August. The seawater below the ice provides enough heat to keep winter temperatures from falling much below about –40º F (–40 ºC).
... At the South Pole, temperatures in January average about –18º F (–28º C), while at the North Pole, the January temperatures range from between about –15º F (–26 C) to about –45º F (–43 C) and perhaps average about –30º F (–34 C). Therefore, the average temperature during the warmest month at the South Pole is only about 12 degrees warmer (F) than the coldest month at the North Pole. January is the only month when the North Pole temperatures are colder than those at the South Pole. So, on a day-to-day basis it’s likely that less than 40 days in a given year are colder at the North Pole than the South Pole.
VOILA !!..Thank ewe DicoverDave...very "cool" link ! great information.
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Historically the Northern and Southern hemispheres exhibit an anti-correlation in temperature. This is at least partly due to the Atlantic's South Equatorial Current. The SEC is one of the only main surface currents that crosses from South to North, and is originally part of the South Atlantic Sub-tropical Gyre. Most of the warm waters of the SEC are redistributed into the Gulf of Mexico through the Yucatan Current and eventually into the Gulf Stream. A large portion of heat transported by the SEC never makes it back to the high latitude Southern Hemisphere, and instead warms the cozy buns of Candians, Americans, and Europeans :) That is at least one mechanism that keeps the NH warmer than the SH during periods of high Gulf Stream transport.
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fwww.soloatlantic.co.uk%2Fsoloatlantic%2Fimages%2Fatlantic_currents.jpg&hash=7109aafbb5037d2a85f149c7186ac120)
Thanks Frethack, This puts a novel addition to the fact that the South pole is cooler than the north. Had not considered the currents. Great stuff !
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Aww, it wasn't really all that klevur. Let's see if anyone else can figure it out (I'll just point out that I didn't spot it because I recognised the South Pole base - you can deduce that the pictures are the wrong way around).
Spill the beans LeeE. Great observation !
Well, as no one has had a go yet...
There's no land at the north pole, only floating ice, so by the time you managed to establish any sort of significant 'base' there, as shown in your 'North Pole' picture, it would have drifted many miles away from the pole. Ergo, if that base was at one of the poles, it could only be at the South Pole.
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Thanks for the great info Karen....In the above it seems to suggest that perhaps the South Pole is colder than the north !
It's obvious the south pole will be colder! For the northern hemisphere-ers of us all know the south pole is the one at the bottom and as heat rises it has to be the coldest!! [^]