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Post by thermostat on Sept 17, 2012 4:44:01 GMT
The earth has two poles.
It is interesting to compare and contrast events at both ends.
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Post by thermostat on Sept 17, 2012 4:53:26 GMT
To begin, I would suggest that the geophysics of a continent surrounded by ocean is quite distinct from the case in the Arctic where an ocean is surrounded by continents.
Further, the planet itself is not symmetrical. The Northern hemisphere is physically unlike the Southern hemisphere.
To initiate the discussion, the question is would one expect weather events at these sites to be similar or different?
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Post by thermostat on Sept 17, 2012 5:18:25 GMT
Melting at the poles is clearly an issue. Maximal Antarctic sea ice extent appears to have increased during the satellite era, while sea ice in the Arctic has diminished. This is a well known observation. Meanwhile, ice sheet volume in Antarctica appears to be decreasing,.
Let's discuss.
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Post by Andrew on Sept 17, 2012 10:52:50 GMT
Antarctica is the driest place on Earth and has a very poor ability to be sufficiently moist to create high snowfall rates.
Most of the worlds rainfall occurs near the equators and then less and less falls as you move away from the equator until inside the artic circle it can be very dry in many places. A warmer world implies more water in the air further away from the equator
The katabatic wind that flows from the highest areas of Antarctica must therefore be a drying wind where ice turns to gas when there is insufficient water in the atmosphere around the ice
Given it is enormously cold in Antarctica and the sea ice is still building it is likely that the land ice in Antarctica was formed when the Earth was warmer and it will not build again till the Earth is much warmer than today.
Incidently at the German Ice station, Niedermeyer? which is nearer the coast they are able to raise their station on hydraulic feet to avoid being buried by the snow and as far as I know snow is still accumulating there. In other places such as mcmurdo sound the katabatic wind is sufficiently strong to blow the snow off the ground down to the underlying surfaces.
Most of the popular ideas in the media about glacial growth are obviously wrong, because precipitation is usually the most important factor in glacier growth and for all glaciers away from Greenland and Antarctica infrequent precipitation means they will be gone very quickly, since generally speaking the main mass of the glaciers is only the accumulated result of about thirty years of precipitation, whereas the Greenlandic and Antarctic continental ice sheets represent hundreds of thousands of years of accumulation.
There is also the factor to consider of the formation of so called lake effect snow near exposed water in Antartica. The more the sea ice builds then the less will be the influence of the lake effect snow on the mainland and the more it will be an influence upon the sea ice.
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Post by magellan on Sept 18, 2012 2:09:07 GMT
Melting at the poles is clearly an issue. Maximal Antarctic sea ice extent appears to have increased during the satellite era, while sea ice in the Arctic has diminished. This is a well known observation. Meanwhile, ice sheet volume in Antarctica appears to be decreasing,. Let's discuss. It was predicted by climate models for the South Pole to warm faster than the North Pole. When it didn't, the "theory" was simply updated. Translation: they make it up as they go along. Meanwhile, ice sheet volume in Antarctica appears to be decreasing,. Based on what? |
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Post by sigurdur on Sept 18, 2012 2:20:19 GMT
I will 2nd that magellan. What is the basis for the idea that the Antarctic Ice sheet is decreasing?
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Post by numerouno on Sept 18, 2012 3:38:28 GMT
"Antarctica is the driest place on Earth and has a very poor ability to be sufficiently moist to create high snowfall rates." Remarkably though there has been enough snowfall to create ice cores to drill into: ftp.ncdc.noaa.gov/pub/data/paleo/icecore/antarctica/vostok/deutnat.txtThe first few lines indicate the depth in meters and the age in years thus: 0 0 -438 0.00 1 17 -438 0.00 2 35 -438 0.00 3 53 -438 0.00 4 72 -438 0.00 5 91 -438 0.00 The present accumulation rate would seem to be about 1/17 meters (about 6 cm) of ice per year at the Vostok station. |
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Post by Andrew on Sept 18, 2012 5:27:01 GMT
"Antarctica is the driest place on Earth and has a very poor ability to be sufficiently moist to create high snowfall rates." Remarkably though there has been enough snowfall to create ice cores to drill into: ftp.ncdc.noaa.gov/pub/data/paleo/icecore/antarctica/vostok/deutnat.txtThe first few lines indicate the depth in meters and the age in years thus: 0 0 -438 0.00 1 17 -438 0.00 2 35 -438 0.00 3 53 -438 0.00 4 72 -438 0.00 5 91 -438 0.00 The present accumulation rate would seem to be about 1/17 meters (about 6 cm) of ice per year at the Vostok station. So ice is accumulating at Neidermeyer at 70 40,8 S 8 16,2 W and at Vostok near the pole And declining where exactly?? |
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Post by thermostat on Sept 19, 2012 2:54:28 GMT
I will 2nd that magellan. What is the basis for the idea that the Antarctic Ice sheet is decreasing? What is the basis for the idea that the Antarctic Ice Sheet is decreasing? Various observations, such as... "Winter warming in West Antarctica caused by central tropical Pacific warming." Nature GeoScience, 2011. www.nature.com/ngeo/journal/v4/n6/full/ngeo1129.html"It has long been known that parts of the Antarctic Peninsula are warming rapidly1. Recently, it has been recognized that significant warming trends extend considerably south of the Peninsula to include much of continental West Antarctica2,3, comprised of Ellsworth Land (79W to 103 W) and Marie Byrd Land (103W to 158 W). West Antarctica is the key
region for heat and moisture transport into Antarctica4, and
the West Antarctic ice sheet has been losing mass in recent
decades, primarily because of increased ice discharge through
outlet glaciers that drain into the Amundsen Sea5. |
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Post by sigurdur on Sept 19, 2012 2:59:57 GMT
thermostat:
The mass loss on West Antarctica has been replaced in East Antarctica. Please bear this in mind. Grace data shows no net loss of ice at this time.
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Post by thermostat on Sept 19, 2012 3:05:54 GMT
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Post by thermostat on Sept 19, 2012 3:20:57 GMT
thermostat: The mass loss on West Antarctica has been replaced in East Antarctica. Please bear this in mind. Grace data shows no net loss of ice at this time. On this subject, "Recent Antarctic ice mass loss from radar interferometry and regional climate modelling. Nature Geoscience, 2008 ww.ldeo.columbia.edu/~tcreyts/GRG/rignotetalNatureGeosci08.pdf "Our results provide a nearly complete assessment of the spatial pattern in mass flux and mass change along the coast of Antarctica, glacier by glacier, with lower error bounds than in previous incomplete surveys, and a delineation of areas of changes versus areas of near stability. Over the time period of our survey, the ice sheet as a whole was certainly losing mass, and the mass loss increased by 75% in 10 years. ... "In East Antarctica, the loss is near zero, but the thinning of its potentially unstable marine sectors calls for attention. In contrast to major increases in ice discharge, snowfall integrated over Antarctica did not change in 1980–2004 (ref. 27) and even slightly increased in areas of large loss17.We conclude that the Antarctic ice sheet mass budget is more complex than indicated by the temporal evolution of its surface mass balance. Changes in glacier dynamics are significant and may in fact dominate the ice sheet mass budget." |
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Post by magellan on Sept 19, 2012 4:29:05 GMT
thermostat: The mass loss on West Antarctica has been replaced in East Antarctica. Please bear this in mind. Grace data shows no net loss of ice at this time. GRACE data is whacked and known to give crap data and interpreted incorrectly since day one, but certain "scientists" used it anyway. We have discussed that at length in the past, but as the original thread was deleted it will need to be regurgitated. I posted this in the Arctic thread, but it blew right past tstat as if were never there. www.agu.org/pubs/crossref/pip/2012GL052559.shtml Antarctic Peninsula (AP) ice core records indicate significant accumulation increase since 1855, and any resultant ice mass increase has the potential to contribute substantially to present-day Glacial Isostatic Adjustment (GIA). We derive empirical orthogonal functions from climate model output to infer typical spatial patterns of accumulation over the AP and, by combining with ice core records, estimate annual accumulation for the period 1855-2010. In response to this accumulation history, high resolution ice-sheet modeling predicts ice thickness increases of up to 45 m, with the greatest thickening in the northern and western AP. Whilst this thickening is predicted to affect GRACE estimates by no more than 6.2 Gt/yr, it may contribute up to -7 mm/yr to the present-day GIA uplift rate, depending on the chosen Earth model, with a strong east-west gradient across the AP. Its consideration is therefore critical to the interpretation of observed GPS velocities in the AP. And this, which tstat won't find on unScrupulousScience. Instead, he resorts to old outdated reports that have already been taken apart in the past. ICESAT Data Shows Mass Gains of the Antarctic Ice Sheet Exceed Losses]The results of ICEsat measurements are in for Antarctica, and it seems those claims of ice mass loss in Antarctica have melted now that a continent wide tally has been made. This was presented in the SCAR ISMASS Workshop in Portland, OR, July 14, 2012 and was added to NASA’s Technical Reports server on September 7th, 2012. H/T to WUWT reader “Brad”. What’s interesting (besides the result) is that the report was prepared by Jay Zwally, whose “ice free Arctic by the end of summer 2012″ prediction is about to be tested in 12 days. It also puts the kibosh on GRACE studies that suggested a net loss in Antarctica. Note there’s the mention of the “climate warming, consistent with model predictions” at the end of the report. They’d say the same thing if ICEsat had measured loss instead of gain, because as we’ve seen before, almost everything is consistent with warming and models no matter which direction it goes.
tstat, how is it you claim to be so interested in understanding and have the latest research at your fingertips but always manage to only find what supports your preconceived notions? tstat, your first link is to Eric Steig's thoroughly debunked Antarctic "warming" that made the cover of Nature in all its glory, only to be another rendition of Mann Hockey Stick math. All he did was try to smear the temperature from the peninsula and spread it out. JUNK. When I have time I'll post the link to the paper than ripped it to shreds. Yet, like the hockey stick, the Steig zombie continues to resurrect from the dead. wattsupwiththat.com/2012/09/08/rcs-dr-eric-steig-boreholes-himself-on-antarctica/Now, anyone who followed the Steig fiasco knows it was proven beyond doubt his rendition of Antarctic temperature profiles was garbage. However, because the IPCC is as or more corrupt than it has ever been, they will probably find a way to include Steig 09 in AR5 as "good science". These so called scientists are nothing more than carnival game operators; a motley crew of scoundrels. Your second link is more of the same climate model folly. When will you learn climate models are little more than very expensive video games? They've been proven wrong time and again yet some still think because millions of taxpayer dollars are thrown at them, they must be a quality product. Kind of like the Chevy Volt. They are to be direct, assumptions by the programmers converted to ones and zeros. The paper was wrong anyway. I have other reports on big problems found with GRACE 2 and 3+ years ago. Alarmist scientists were misusing GRACE data plain and simple. |
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Post by thermostat on Sept 19, 2012 4:57:15 GMT
As I said previously; "The earth has two poles.
It is interesting to compare and contrast events at both ends. "
In this regard, it is useful to understand the challenges of investigating events in these remote locations. In particular, however remote and inaccessible the Arctic may appear, the Antarctic is even more difficult to study. Just looking at the geography, where are your assets coming from? where do you set up your base? The logistical challenges are substantial, in comparison to studying the Arctic.
As a result, in late 2012, we have substantially less data about the Antarctic to base a discussion on.
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Post by Andrew on Sept 19, 2012 8:00:10 GMT
As I said previously; "The earth has two poles.  |
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