knocker
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Posts posted by knocker
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Just been looking at the CFS 300 day forecast for London and the coldest month seems to be March with a brief cold spell in January. Not much likelyhood of snow and certainly not in Cornwall. Whoopee, I hope they are right but not holding my breath.
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I can only repeat what ch has posted, the data he and GP placed in this thread last autumn is well worth reading for anyone new or indeed to remind some of us just what the links are and how to understand them.
Hopefully ch you will do a similar thing to last Autumn into winter with GP hopefully also posting his thoughts.
For those new to much of this, yes to oldies like me its got some difficult concepts to try and get your head round but please do take the time to read the posts from 2009, and again do ask questions, that is the only way any of us learn.
end of another jh sermon!
Will follow your advice John.
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Noted physicist Hal Lewis quits American Physical Society over the "global warming scam"
quote from his resignation letter:
"It is of course, the global warming scam, with the (literally) trillions of dollars driving it, that has corrupted so many scientists, and has carried APS before it like a rogue wave. It is the greatest and most successful pseudoscientific fraud I have seen in my long life as a physicist."
Well he wouldn’t be the first great mind to go slightly gaga towards the end. If I remember correctly Bertrand Russell was moving in a parallel universe in his twilight years. I did hear a rumour that Lewis was running for president of the Bulverist Society.
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certainly a wide spread snow event in the south and west even at low levels there were some heavy falls.
If it's the same event (I'm afraid my memory isn't what it was) I travelled overnight by train from Glasgow and we hit the snow at Bristol. It really came down but fortunately the trains kept running as far as Truro before giving up the ghost. I can't remember how I got to Falmouth, if in fact I did. It was a very shortlived event down these parts.
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Those are certainly some interesting figures, if we keep with a negative NAO for the rest of the year, then this year will dwarf previous negative years.
NAO
-0.5 in 1998, currently -1.05
AO
-0.5 in 1996, currently -1.00
Those are quite astonishing figures.
It appears to have gone positive so far for Oct.
NAO +.32
AO +.25
PNA +.27
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Ever since two megalomaniacs combined to destroy the coal industry, followed by successive governments failing to implement a coherent energy policy, the predicable outcome is now occurring. Much, I suspect, to the detriment of the consumer.
Supplies of North Sea gas are set to tumble a further 9 per cent this winter, forcing Britain to import more of the fuel from overseas than ever before, National Grid said yesterday.
In its annual winter outlook report on the state of Britain’s energy supplies, National Grid said that 55 per cent of the gas used to heat homes and factories this winter would need to be imported from countries such as Norway, Qatar, Trinidad, Algeria and the Netherlands. That is the highest level on record and double the 27 per cent level of imports recorded in 2007.
http://www.thetimes.co.uk/tto/business/industries/naturalresources/article2758401.ece
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Yes but for how long... six weeks? The equator would be at that rate 52 weeks a year.
Actually the equator can be a bit of a red herring regarding solar radiation. Between 6 deg.N and 6 deg.S the sun's rays remain almost vertically overhead for only 30 days during each of the spring and autumn equinoxes, allowing little time for any large build-up of surface heat and high temperatures. On the other hand, between 17.5 and 23.5° latitude the sun's rays shine down almost vertically for 86 consecutive days during the period of the solstice. This longer sustained period, combined with the fact that the tropics experience longer days than at the equator, makes the maximum zones of heating occur nearer the tropics than the equator.
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Going.........And Almost Gone.
Two of the approximately 26 remaining glaciers (under snowfield) at Glacier National Park, MT, June 19, 2010. In 1850, the park had an estimated 150 glaciers; all glaciers expected to be gone by year 2030.
Courtesy U.S. Geological Survey/photo by Connie Loper.
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Ice Shelves Disappearing on Antarctic Peninsula
This image shows ice-front retreat in part of the southern Antarctic Peninsula from 1947 to 2009. USGS scientists are studying coastal and glacier change along the entire Antarctic coastline. The southern portion of the Antarctic Peninsula is one area studied as part of this project, and is summarized in the USGS report, "Coastal-Change and Glaciological Map of the Palmer Land Area, Antarctica: 1947—2009" (map I—2600—C).
http://www.usgs.gov/...cle.asp?ID=2409
Credit: U.S. Geological Survey
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Short lived hailstorm made this bloke go nuts yesterday!! its like they dont often get this kind of weather??
A friend of mine went on holiday to Arizona for the last two weeks of September. Prior to her leaving I said watch out for the monsoon. She gave me a perculiar look whilst taking a couple of steps back and I could almost hear her thinking, "streuth, he's lost it again".
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Madan Shrestha of the Nepal Academy of Science and Technology remarks, "We have ample scientific evidence to prove that climate change is causing the Himalayan glaciers to retreat." Don't tell the IPCC.
http://ipsnews.net/news.asp?idnews=53044
Freshwater is flowing into Earth's oceans in greater amounts every year, a team of researchers has found, thanks to more frequent and extreme storms linked to global warming.
http://www.sciencedaily.com/releases/2010/10/101004151700.htm
And a new definition for "extracting the urine".
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Further to the debate.
What Role Might Climate Change Have Played in the Recent East Coast Deluge?
The heavy rains that inundated the East Coast during the last week of September were the result of a rare combination of ingredients — namely a wide-open, 3,000-mile-long pipeline of tropical moisture extending from the Caribbean all the way up to Maine and the Canadian Maritimes, a stalled frontal boundary, and multiple waves of low pressure that rode along that boundary. Many cities set new single and multiday rainfall records, and the rain led to severe flash flooding from North Carolina to New York State.
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Contrary to media reports, serious flooding has occurred before at Boscastle: in late-October 1996 when ex-hurricane Lili delivered a combination of heavy rain and high tides that inundated the lower part of the village; in the Junes of both 1958 and 1957 when sudden floods developed in circumstances similar to last Monday; and in July 1847 when a much broader region was affected.
http://www.weatheronline.co.uk/reports/philip-eden/Some-facts-and-figures.htm
By coincidence in this months Geographical magazine.
Extreme weather events are becoming both more frequent and more severe, causing profound problems for the developing world. Some scientists believe that these disasters are the result of man-made climate change, but can a link be proven? Mark Rowe investigates
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Better than a big, walloping, fat Mid Atlantic ridge sitting there I think we can all agree (unless of course you prefer the colder, cloudier prevailing conditions you get from such a yucky and boring mid atlantic ridge setup)
Like this you mean although I'm rather stretching the definition of ridge.
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How would a computer model know when a butterfly might decide to flap its wings in Africa? Or when a packet of energy might form over the northern Gulf of Mexico to create the genesis of a winter storm? Now if those butterfly wings are actually subtle energy inputs from predictable astronomical events or geomagnetic variations, you've got something. If not, then all the effort in the world will fail to solve this riddle, it just won't be possible to model such things accurately.
Yet, if the large scale features are based on the energy set-up of external drivers, then it stands to reason that the variations within the large scale features would become predictable as second-order variables.
I don’t for one moment claim any great knowledge on this subject and it is probably very presumptuous of me to enter to enter the fray but if you don’t ask you don’t learn. If I’m reading this correctly you are saying the energy set-up of external drivers are predictable astronomical events or geomagnetic variations.
In another post (apologies for taking pieces out of context) you say “When I see similar peaks in various index values from data sets in two different parts of the world (but similar climates) then I suspect that we are on the road to a predictive framework.â€â€¦..and go on to say “By ‘index value’ I mean the profiles of certain postulated ‘drivers’ above and beyond the most obvious one that everyone recognizes, the Sun in its annual variation in apparent latitude.
So my question (hopefully not too stupid) is does your research bear any similarities with that of Dr Theodor Landscheidt that concentrated on long-range forecast of U.S. drought based on solar activity? In this, as far as I can ascertain, he linked various events such as ENSO, NAO, etc, with to cycles in the sun’s orbital motion around the center of mass of the solar system. He is in fact saying that as the relationship is based on astronomical data that can be computed, the forecast could be extended farther into the future. For more detail:
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A new report supporting the mechanical scenario of ice shelf collapse.
Depicting a cause-and-effect scenario that spans thousands of miles, a scientist at Scripps Institution of Oceanography at UC San Diego and his collaborators discovered that ocean waves originating along the Pacific coasts of North and South America impact Antarctic ice shelves and could play a role in their catastrophic collapse.
http://www.scienceda...00211175219.htm
Abstract from the paper.
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What happens next? That's a very good question. There is no definitive answer of course but it can't be ignored. As long as we don't get a sediment slide in Antarctica like the one that occured in the Mesozoic period which covered an area of at least 20km x 6km. We can do without further complications.
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However bizarre it first seems the midsummer sun (24hrs) over the Arctic delivers the biggest wallop of energy (per sq metre of surface) than anywhere on the planet!
http://www.applet-ma.../insolation.htm (scroll down to the table and check the summer solstice figures)
around 12.64 Kw/m2 (the equator max's out at 10.22Kw/m2)
I must admit I find these figures very odd and frankly don't really understand them. My understanding has always been along these lines unless they are talking about something else such as measuring the energy prior to it being reflected. A tad deceptive if they are. On a second reading I realise the refinements have been ignored.
Effect of latitude
Different parts of the earth's surface receive different amounts of solar radiation. The time of the year is one factor controlling this, more radiation being received in summer than in winter because of the higher altitude of the sun and the longer days. Latitude is a very important control because this will determine both the duration of daylight and the distance travelled through the atmosphere by the oblique rays from the sun. However, actual calculations show the effect of the latter to be negligible in the Arctic, apparently due to the low vapour content of the air limiting tropospheric absorption. Figure 2.7 shows that in the upper atmosphere over the North Pole there is a marked maximum of solar radiation at the June solstice, yet only about 30 per cent is absorbed at the surface. This may be compared with the global average of 48 per cent of solar radiation being absorbed at the surface. The explanation lies in the high average cloudiness over the Arctic in summer and also in the high reflectivity of the snow and ice surfaces.
Source: Atmosphere, Weather & Climate (seventh edition) Roger G. Barry, Richard J. Chorley.
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Thanks W.S. (Rugby L. was my mainstay back in the day......when Swinton had a ground and Salford were just plain Salford!!!)
The prospect of any (relatively) sudden hike in sea levels (10cm+ or so) coupled with a spring tide/Strom swell has had me with concerns and I would like other folk's inputs.
We are becoming inundated with evidence for sudden climate 'snaps' , be they cold or warm, and rapid shifts in the global setup. With that as a backdrop (in a warming world) some folk ask 'how'? and though I'm reassured from many quarters that E.A.I.S. is 'stable' if the 'collapse' is mechanical (and not 'melt') then there seems to be scope for a rapid alteration to the mass balance there.
I'm not sure the E.A.I.S. is the major concern. I suspect the major problem is the W.A.I.S. and people started worrying about this six years ago. A press release from BAS at the time explains it better than my woffle. http://www.antarctica.ac.uk/press/press_releases/press_release.php?id=47
21 September 2004 No. 13/2004 Scientists have found a remarkable new structure deep within the West Antarctic Ice Sheet which suggests that the whole ice sheet is more susceptible to future change than previously thought. The discovery, by scientists from Bristol University and the British Antarctic Survey in collaboration with US colleagues, is reported this week (September 24) in the international journal Science. The stability of the West Antarctic Ice Sheet has been hotly debated since the 1960s because of its potential to raise global sea level by around 5 m over several centuries. The potential impacts of a major change in the West Antarctic ice sheet are severe ? sea level rise will be fantastically expensive for developed nations with coastal cities and dire for poor populations in low-lying coastal areas. Lead author Prof Martin Siegert of Bristol University said, ?There is a great deal of speculation that global warming may cause sea levels to rise due to the melting of ice sheets. Until now, scientific observations suggested that change to the West Antarctic Ice Sheet would be restricted to the edges implying that large-scale instability of the ice sheet is unlikely. This new discovery deep within the ice means that we need to re-think our current assessment of the risk of collapse of this ice sheet.? The structure - a distinctive fold in the ice, 800m deep by 50 km long - was detected using ice-penetrating radar. Ice sheets normally consist of flat layers of ice, so finding this huge fold was a complete surprise. Its presence suggests that a few thousand years ago surface ice at the centre of the ice sheet was moving rapidly and being ?drawn down? towards the bottom of the ice sheet. More recently the rate of the ice flow has changed from fast to slow. The direction of flow has also changed. The most likely explanation for these changes is the ?switching-off? of a large ice stream at the margin of the ice sheet several centuries ago. These changes imply that the centre of the ice sheet is more mobile than scientists previously realised, requiring them to rethink existing models. ENDS Issued by the University of Bristol & British Antarctic Survey Press Offices The University of Bristol Press Office: Cherry Lewis: (w) 0117 928 8086, (m) 07729 421 885, (e) cherry.lewis@bristol.ac.uk British Antarctic Survey Press Office: Linda Capper (w) 01223 221448, (mobile) 07714 233744 (h) 01480 880302; (e) L.capper@bas.ac.uk Athena Dinar (w) 01223 221414; (mobile) 07740 822229 (h) +44 (0)1223 513298 (e) a.dinar@bas.ac.uk Notes for editors: The paper, Ice Flow Direction Change in Interior West Antarctica by Martin J. Siegert, et al. is published in Science. Vol 305, 24 September 2004 Picture editors: Video footage and stills of Antarctic ice sheets, ice streams and general views are available from the BAS Press Office Contacts : Professor Martin Siegert, Centre for Polar Observation and Modelling, Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Tel: +44 (0)117 928 8902. Email: m.j.siegert@bristol.ac.uk (m) 07780 703008 Dr Edward King, British Antarctic Survey, Tel: +44 (0)1223 221580; Email ecki@bas.ac.uk Risk Estimation of Collapse of the West Antarctic Ice Sheet by David Vaughan and John Spouge, was published in Climatic Change January 2002, Volume 52, page 65-91. The authors used engineering risk-analysis techniques to conclude that there is a 5% chance of major sea level rise (1 metre per century) due to disintegration of the ice covering West Antarctica. This was the first study to gives a realistic assessment of differing scientific opinions in a useful way for policy makers. West Antarctic Ice Sheet (WAIS), which contains 13% of all the ice on the Antarctic continent. Currently this ice sheet is anchored to the rock beneath, much of which is below sea level. However, in past warm periods, the ice sheet thinned and disintegrated into floating icebergs. If the WAIS completely disintegrated, it would raise global sea levels by about 5 metres over several centuries. Ice sheet The Antarctic ice sheet is the layer of ice up to 5000 m thick covering the Antarctic continent. It is formed from snow falling in the interior of the Antarctic which compacts into ice. The ice sheet slowly moves towards the coast, eventually breaking away as icebergs which gradually melt into the sea. The ice sheet covering East Antarctica is very stable, because it lies on rock that is above sea level and is thought unlikely to collapse. The West Antarctic is less stable, because it sits on rock below sea level. If the ice sheet does collapse, it is more likely to be part of a natural collapse cycle, or as a response to climatic change that occurred many thousands of years ago, rather than a response to current climatic change. British Antarctic Survey is responsible for most of the UK?s research in Antarctica. It is a component of the Natural Environment Research Council. More information about the work of the Survey can be found on our website.
Not surprisingly the Dutch take this quite seriously as about half the Netherlands is at risk.
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I wouldn’t disagree with that. Also the Vostok ice core record is of some significance. The core gave direct evidence of past changes in carbon dioxide content of the atmosphere with variation over 100,000 years between glacial and interglacial periods and lesser cyclic changes with a period of some 21,000 years. These results show a close correlation with the temperature record (determined by the deuterium content and which themselves are in good agreement with the marine records as far back as 110,000 years). Thus, carbon dioxide concentration emerges as the major factor forcing, or following, temperature changes. I’ll opt for the former although it has been suggested that that these are triggered by and amplify insolation changes brought about in both the northern and southern hemispheres by orbital forces.Defo!
Once freed of the other land masses the unique circulation we see today was free to evolve. We must remember though that the continent has carried a lot less ice at times (in recent geological history) than today and the evidence of the partial melt 125,000yrs ago is something we must consider as global temps are heading in that direction? I think it unwise not to look at what a sustained period of warmth meant for both Greenland and Antarctica 125,000yrs ago even if our 'warm up' is much faster than back then and may cause a 'changed' response/timescale of change to what was experienced back then.
We now have evidence from southern Greenland (of this 'warm episode' )and ,more recently , evidence from Antarctica. Both seem to point to an imminent readjustment in current sea levels?
Edit: Would anyone wish to have a stab at how an increase of sea levels will impact the grounded ice in Antarctica?
I'll have a think about your question re. sea levels (rather depends on the size) but just off to watch the rugby leave.
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Well we won't beat this one to death. Rather depends on whether picog meant present day Antarctica when the Circumpolar Current became established 25 million years ago, or the millions of years prior to that.
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I think you'll find that Antarctica has been ice free for most of it's history as a 'continent'.
I’ve given this a bit more thought and there are some loose ends somewhere. The following is an extract from “A History of Antarctic Science†by G.E. Fogg. This was written in 1992, so do I take it that recent paleo evidence has somewhat altered the thinking on this?
"The palaeontological evidence makes it clear that Antarctica was not always glaciated to the extent that it is now and that it had experienced climatic amelioration, for example, in Triassic times. Before that, in the severe Permo-Carboniferous glaciation, Antarctica was evidently the centre from which ice flowed outwards to leave tillites and other evidences of glacial action in other parts of Gondwana. The time of the onset of the most recent glaciation was speculative when Adie (1964) wrote his review but the finding of fossil penguins in the late Oligocene to lower Miocene of northern Graham Land suggested that the climate was getting cooler then. It seemed that the present ice-sheet had begun to form in the mid-Pliocene contemporaneously with that in the northern hemisphere. By the early 1960s there was considerable evidence from work on raised beaches, wavecut platforms, submerged sea caves revealed by SCUBA diving and morainic deposits interbedded with lava flows, of late Tertiary fluctuations in sea-level in the Peninsula and Scotia Arc area but accurate dating had not been carried out (Odell, 1952; Adie, 1964). These fluctuations seemed to have been greater in West Antarctica, where they were related to worldwide sea-level changes which caused the major outlet glaciers to rise in level as their outlets dammed up. The ice-sheet in East Antarctica seemed to have been more stable (Hendy et al., 1979). Drilling during the McMurdo Sound sedimentary and tectonic study showed that glaciomarine conditions in that area go back to late Palaeocene, 60 million years ago (Webb, 1983). A global temperature drop was inferred from isotope records to have occurred at the end of the Eocene, 40 million years ago, but there was no evidence from the Antarctic to support this. Ice-sheet formation presumably began about 25 million years ago when the continents comprising Gondwanaland had separated sufficiently to allow the Circumpolar Current to become established and isolate Antarctica. The major build-up of the East Antarctic ice-sheet appeared from oxygen isotope determinations on benthic foraminifera recovered from Deep Sea Drilling Project cores obtained by the Glomar Challenger to have started in middle Miocene, 12 million years ago (Savin, 1977; Frakes, 1983)".
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Okeydoke. I stand corrected GW.
Antarctic Peninsula: rapid warming.
The Antarctic Peninsula is a rugged mountain chain generally more than 2000 m high, differing from most of Antarctica by having a summer melting season. Summer melt produces many isolated snow-free areas, which are habitats for biological communities of primitive plants, microbes and invertebrates, and breeding grounds for marine mammals and birds. During the last half-century, the Antarctic Peninsula has experienced dramatic warming at rates several times the global mean. This warming has been the focus of considerable recent research, and substantial progress is now being made in understanding the causes and profound impacts of this warming.
http://www.antarctic...c_peninsula.php
A brief note regarding the meteorology of the Antarctic.
The poleward air circulation in the tropospheric vortex leads to subsiding air over the Antarctic Plateau and outward flow over the ice sheet surfaces. The winds represent a balance between gravitational acceleration, Coriolis force, friction and inversion strength. On the slopes of the ice sheet, there are stronger downslope katabatic flows, and extreme winds are observed in some coastal locations. Cape Denison, Adelie Land, recorded average daily wind speeds of 35kts on over 60 per cent of days in 1912-13. This was the famous Douglas Mawson expedition.
The Antarctic is the windiest place on Earth.
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Is there any evidence that Antarctica has been ice-free, like the Arctic has been in the distant past?
Depends what you mean by evidence. Some resarch has suggested that antarctica could have been ice-free at some point in the past but to the best of my knowledge that's as close as it gets.
New Research
in Climate Change
Posted
Fifty years of U.S. Geological Survey (USGS) research on glacier change shows recent dramatic shrinkage of glaciers in three climatic regions of the United States. These long periods of record provide clues to the climate shifts that may be driving glacier change.
http://pubs.usgs.gov/fs/2009/3046/