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I stumbled on to this site while surfing. I recently finished the book by the doctor who was evacuated several years ago. Since reading that book and surfing all over the web, I have become fascinated with the South Pole.
First, what is the best website to get the current South Pole weather? I’ve looked at http://www.wunderground.com, but it doesn’t give the barometric pressure.
It does, however, give the forecast and that is the basis of my next question. I am a retired airline pilot so I think I have a pretty good understanding of weather. Can someone there, in a few paragraphs, explain to me how weather develops and moves at the South Pole? In my mind, there is no west to east flow as I’m so familiar with. I live just north of San Francisco. My weather comes off the ocean and is a mixing of tropical weather systems from around Hawaii and systems from the Gulf of Alaska. The jet stream is the steering factor.
What goes on at the South Pole? I can’t seem to stretch my mind to a place where there is no Coreolis Force.
I’m looking forward to a good education!
Bob
Sonoma, CaliforniaHi RChaber,
Here is another site for weather observations from the South Pole
http://www.antarctica.ac.uk/met/metlog/latest-met/89009.latest-met.html … t-met.html
(see a report, down at the bottom of this post)As for the pressure readings, there is no MSL readings done there, hence your missing the 4PPPP group in the synoptic 6 hourly report.
But you will see in the plain language weather data there is station pressure listed ( 686.8 Millibars/hPA)
I am not down at the SP but I spent a year as a surface/upper air weather observer there. You may want to read about katabatic winds. This is something I remember well, because when the winds at the SP came from the southeast (grid) it was a much colder wind. It was cold air from higher up on the Antarctic Plateau flowing downward.
To get a idea of how the weather systems circle around the huge continent, you can run animations of the forecast models at
http://box.mmm.ucar.edu/rt/mm5/amps/
I use 500 Mb or 300Mb for the height.
The winds at the SP do not get very strong (compared to lower elevations along the coast) and being up high and dry (desert) it does not see much in the way of precipitation accumulation. Snow grains and ice crystals are very common there.
Hope these web sites give you some more info on the weather patterns down on the ice.
http://www.comnap.aq/comnap/comnap.nsf/P/Pages/Operations.Meteorology/#1 … orology/#1
http://www.bom.gov.au/weather/ant/handbook/handbook.shtml … book.shtml
Here is the synoptic report from the SP
Station: 89009 Date 2005/3/21:00
Station pressure: 686.8; MSLP: null; PTND: 0.4 (1 (code table 200))
T: -48
Dew T: null
Wind Dir, Speed, Unit: 350 14 kts (anemometer)
Cloud (oktas): 8, 7 (Low Type), 5 (Mid Type), null (High Type), (Base (m): 300)
Weather: Present: 77 (Solid ppn not in showers) / Past: 7 (Snow, or rain/snow), 4 (Ice fog, fog or thick haze)
Actual Synoptic Report:AAXX 21004 89009 41412 83514 11480 36868 51004 77774 8475/ 333 11480 21559 84710 86336
Thank you for this reply. This is exactly what I was looking for. I’ll spend some time on the websites you suggested. Then, no doubt, I’ll be back with more questions!
Meanwhile, why is station pressure and not MSL reported? Is this common elsewhere?
Bob
Sonoma, CAI can’t remember the exact reason why the MSLP was not reported but I think it is because the reduction of station pressure to mean sea level pressure would have some error to it due to the South Pole Station’s high altitude (2835 meters). I’ll see if my meteorologist friend knows about this the next time I see him.
As a pilot, would you be more interested in the station pressure and the altimeter setting?
http://ams.allenpress.com/amsonline/?request=get-abstract&issn=1520-0493&volume=132&issue=08&page=1952 … &page=1952
You ask an interesting question. As a pilot I always used the altimeter setting which I think is essentially station pressure.
This is the way we’ve always done it. Almost all of my flying career was in the U.S. and what little I did elsewhere was pretty much in major cities mostly near sea level. Everywhere I ever went we flew at low altitudes by reference to the altimeter setting obtained from a nearby station. At high altitudes we flew at Flight Levels, which required the altimeter to be set at 29.92″. In the U.S., the changeover point is 18,000 feet. Outside the U.S. there are different changeover altitudes designated by the appropriate authorities. Whatever changeover altitude is specified puts the airplane way above any terrain.
For probably 50 years we have descended into airports on instruments down to 200 feet above the runway using that airport’s altimeter setting. Obviously, there are temperature and other errors that creep in, but I guess the 200 foot minimum has been proven safe even with cumulative errors in the same direction.
To go lower than 200 feet without seeing the runway, a radio (really radar) altimeter is used. This bounces a signal off the ground and is probably accurate to a few inches
I have never been to or been trained to go to remote, high altitude places in this big world. Maybe they do things differently. I don’t know.
I did read the link you provided about pressure errors in the high altitude areas of the western U.S.. Fascinating! I have noticed that some high altitude airports have a minimum altitude of 250 feet rather than the standard 200 feet. I always assumed that it was because of obstructions from nearby mountains. There are many descent rate and climb rate calculations that go into designating a minimum altitude for an airport. However, after reading the link, maybe there is a factor inserted due to altimeter setting error at high altitude airports. I don’t know this either.
As a commercial pilot you learn to follow procedures and it all works out fine. There are many, many cases where someone like me will never know everything (anything?) about what is behind the creation of the procedures. I knew to check the air pressure in the tires, but I have no idea how “they” decided that the pressure had to be 145 to 160 psi. (And yes, there was a temperature correction).
Because I was raised on altimeter settings, it is what is most useful to me. We had a heavy rain last night and the barometer went down to 29.61. I know that is low. If every place reported station pressure, it wouldn’t mean much to me when Las Vegas reports, because I don’t know, offhand, how high it is.
Finally, by every station reporting sea level pressure, I used to be able to locate a front’s position just by inspecting a few reports. For example, if I looked at a few hour’s reports from OMA, DSM, MLI, RFD, I could spot the location of a front and make my own assessments of wind shifts and turbulence. This would be very difficult without each station reporting sea level pressure.
I guess I just wrote kind of a lot. Maybe you just wanted a yes or no!
Now, how come South Pole doesn’t seem to report dewpoint?
Bob
Sonoma, CAYour right, we need MSLP to see the weather changes as they occur on the
weather map. I remember being out near the skiway at the SP and a LC-130 landed out of nowhere, which was very near me and it must of been in a minus 1/4 of a mile ice fog obscuration I guess if your a good pilot and are used to landing at NPX you can put the plane down on a skiway with an almost total surface based obsucration. Maybe someone on the iceboard will know if the ANG planes that land at NPX use radar altimeters?<"I guess I just wrote kind of a lot"> Naw never! 😀
As far as I remember, we were not required to report dew points lower than -35 or something like that temeprature. It may have changed since then (early 1990s) but when it gets that cold, I do not think DP plays a part in the big picture. Now wind chill makes more news there than dew point. I can remember a few times out walking around for 45 minutes in -165F wind chills 😯 Coldest wind chills this winter in South Florida were in the mid to upper 30s, so those -165 WCs are a chilling memory!
Hope your weather clears up and settles down out there in Sonoma!
This link doesn’t want to load.
I remember being out near the skiway at the SP and a LC-130 landed out of nowhere, which was very near me and it must of been in a minus 1/4 of a mile ice fog obscuration I guess if your a good pilot and are used to landing at NPX you can put the plane down on a skiway with an almost total surface based obsucration. Maybe someone on the iceboard will know if the ANG planes that land at NPX use radar altimeters?
I’d love to hear some stories from people who have flown in there. Is anyone out there who’d like to share some experiences?
By the way, back to my original question about SP weather. A lot of my problem was that I had no idea how big the continent is. The info about katabatic winds is another phenomenon I knew nothing about and its effect on the sea is almost unbelieveable.
Bob
Sonoma, CAHi ! If Antarctic ice is melting, how is it that a tall metal crane put in the middle of the Antarctic in the Sixties, was more than half buried by ice by the Eighties? There is a photograph of the crane on http://www.iceagenow.com.
Deepening ice and metal cranes do not tell lies!! How many “unbiased” scientists are there in receipt of “research grants” involving global warming etc ?
Explain the photograph , please !!!Thanks for the web site, looks interesting…will have to read soon.
The snow keeps piling up over on the Ice Sheets. But what interests me is what is happening under those huge glaciers…?
Ever read about the disapearing permafrost up in the Arctic areas?
I’m not a research scientist here but I’ll try to digest some of what I’ve learned about global warming. The problem with describing changes in antarctica is that the continent is about the size of North America. It’s like comparing Florida to Arizona to Canada. The effects will be different in different places.
One of the first big changes should be snowfall. The frigid air we have is too cold to hold moisture. The amount of snow that fall is actually small. It’s been said that we are drier here than the Sahara Desert. I’m not sure how true that is, but if the air were to warm, it would hold more moisture and it would snow more here. The more the air warms the more the crane gets buried.
Most of the worlds fresh water is locked up in the Antarctic ice sheets and glaciers. In some places the ice is over 2 miles thick. The glaciers flow like toothpaste out to the sea mostly as a result of weight and gravity. Right now we have vast iceshelves grounded on the ocean bottom that act as dams holding back the glaciers. Look on a map at the Ross Ice Shelf to see how big they are. Any ice touching ground can’t raise sea level. As long as the iceshelves remain intact and continue to contain the glaciers and icesheets, in a global warming environment you would expect the amount of ice in antarctica to increase, and sea level rises from Antarctica to remain somewhat constant.
The big fear is what happens when things warm enough to break up the iceshelves. There exists a potential for the pent up to flow fairly quickly into the ocean. Once the ice hits the ocean and floats, that’s when you would begin to see quick rises in sea levels.
At this point there has been at least one iceshelf that has broken up.This is a VERY simplistic view of things. There are lots of variables dealing with atmospheric and oceanic currents, amount of reflected sunlight etc etc. It’s part of the reason that so much of the research down here deals with potential global warming mechanics.
Hope this helps and if any of the science people want to correct my errors. feel free
That’s a good summary. I would add that, when thinking of “global” warming, you have to think of it in a global context. This means that some places may get warmer, and some colder, but overall the temperature is rising. These are natural, localized variations in climate.
One of the mistakes (or purposeful disinformation) that a lot of anti-warming advocates make is to point at one place that’s cooling off and say, “See? It really isn’t warming!” as if localized changes were a direct indicator of broader global events. They’re not.
For a debunking of the pseudo-science presented against global warming, including Michael Crichton’s latest tripe and other misinformation that’s so rampant in the media and politics, see the web site:
Glenn and Mike, very good points about global warming.
One thing is for sure is that it is a very serious issue and the politicians and corporations should really do as much as possible to reduce the CO2 emissions. If the ice sheets ever do slip into the ocean, I will be moving my family to Colorado! Florida will be under the sea!
More views and politics…..
http://www.motherjones.com/news/featurex/2005/05/world_burns.html … burns.html
One interesting thing I did learn is the reason the United States wouldn’t sign the Kyoto protocols on global warming. It seems that when they wrote the standards for the big countries to reduce pollution, they excluded china for some reason. The scenerio would be that businesses in the States would have shut down, but could move to China and pollute to their hearts content. The US felt it would cripple their economy. Bolster China’s economy and there would be no reduction in CO2 to show for it. Unless the standards were instituted fairly they decided not to sign it.
I don’t know too much about the Kyoto treaty, but I thought that the other less developed nations wanted more time and or credits to realease the green house type gasses into the atmosphere. Reason being, that they were just getting their industrialized economies going and nations like England and the US have been sending up the gasses since the dawn of the industrial revolution at the the turn of last century. I would like to see all nations scale back the emissions.
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