Sigmoid is a common term in structural geology. En-echelon tension gashes in incipient shear zones take on a sigmoidal shape as they rotate and extend as shear strain develops.

Probably needs a more layman's explanation Paul.

In areas with rocks that have been affected by tectonic forces, causing folding, some of the stresses the rocks experience are shear forces with the rocks being deformed in opposing directions. One product of these forces is the opening up of fractures (commonly filled with minerals such as quartz or calcite). However as the stress continues the earlier fractures and their fills are rotated so that, as the fracture propagates at each end, these new additions have the same orientation as the original fracture but that has now been reprinted. Progressively this reorientation of older parts of the fracture causes asigmoidal shape to form. It really would be best if this could be illustrated with a photograph, but my steam powered tablet is incapable of doing this [I know, buy a better computer!]. Perhaps Paul could oblige - they can be quite beautiful and strange.

Alan Kendall, probably needs a better Blue Peter explanation.

Valerie Singleton would have cooked a a cake with different coloured layers of sponge, glued together with sticky gooey stuff, some of which set harder than others.

John Noakes would have appeared on set, and rolled and folded the cake, whilst Valerie sprinkled sugar, and diced glace cherries mixed with crushed nuts, from above. This rolling/folding sequence would have been filmed, whilst some one shook the camera, so that us young viewers at home really got the the non 3D/SurroundSound impression of the forces of an earthquake.

Obviously some of the sticky gooey stuff which had set hard, would have cracked, pinging bits of itself, plus sugar, plus cherries and crushed nuts in all directions, up/down/left and right across the studio floor to be hoovered up by a baby defecating elephant, accidently left unnoticed in the studio.

With another quick fold or two of the cake, and a pancake fip for good luck, it is almost impossible to work out the sequence of construction, and the scene concludes with more camera crew tremors caused by the elephant wanting the entire cake

Of course, if you try to explain this sort of science to the kids of today, they won't believe a word of it

golf Charlie. You have perhaps forgotten the untold tectonism caused by the Blue Peter pets as they tried to lay waste to each other. And somewhere they must have used loo paper rolls and a plastic soft drink bottle. Perhaps the latter, full, could represent volcanism spreading further joy and elephant lubricant.

I think it is officially swept under the carpet.

Martin A, Radical Rodent

Sigmoid. I should have remembered. Thank you.

At your service, EM.

Paging Raff. Clean-up in aisles 1 through 5.

Dung & Martin A

The problem with attempts to sweep Mann's Holy Hockey Stick under the carpet, is not the imaginary flat bit, which can be slid under any carpet bagging Climate Science Peer Review, but goes against accepted Geology, History, Archaeology etc etc, but the remaining scarily priapic uptick. As long as climate scientists pretend it is not there, they will keep tripping over it.

But if climate scientists beat it flat, they will have nothing else to do.

This is why ocean acidification has gained such importance in alarmist minds. Polar bears may dissolve. Or even turn bright green, or something even more unimaginable, that someone is desperately trying to think of, before the money runs out.

What geologists might say about the records of acidity etched into limestone, I would love to know. The Great Barrier Reef and White Cliffs of Dover COULD dissolve quicker than an alka-seltzer, if some alarmist claims are to be believed.

golf Charlie j'acous (or whatever)

Of falsely dismissing the great shibboleth (or whatever) of the holy hockey stick beneath the carpet of ignorance.

Of self interest: been banging on recently about his great love of the south coast ports ("they are rising and shall achieve greatness again") which now we discover he fears will be lost due to increasing amounts of tiny, tiny hydrogen ions that no-one has ever seen. No concern expressed whatsoever for the Gower, the Great Orme or the Durham coast. Perhaps he believes the Welsh Assembly or the mythical Northern Powerhouse will take responsibility but he doesn't speak those languages.

Of falsely claiming the parlous (or whatever) state of his boat's hull, likened to certain porous foreign cheeses) is the result of the previously mentioned tiny, tiny hypothetical H ions, and not to time wasted on excessive blogging.

Of subliminal advertising for a remedy for the aforementioned false scares. The prosecution believes golf Charlie will propose recommissioning Britain's new and mighty aircraft carriers as giant antacid dispensers set to plough the English channel ( or La Manche if the Charles de Gaul (whatever!) joins in).

If he be deemed guilty, your Grace, what should be a fitting punishment for such heinous crimes?

RR - 'through' is valid English usage

http://english.stackexchange.com/questions/44686/through-or-to-for-expression-of-range

Dung

Is the Hockey Stick officially debunked or is Mann still holding out?

Do you mean the analytical technique used in the 1998 paper, or the temperature trend shown in Andrew Montford 's least favourite graph?

The analysis technique had faults and has long since been replaced by better methods.

The Hocky Stick shaped graph has appeared over and over again in 70+ proxy studies since.

Mann's method was imperfect. He would tell you himself.

His graph has been repeatedly validated by other researchers as a description of the temperature pattern Earth experienced over the last 1000 years.

Entropic man. Sorry cannot match your priceless humour re the Holy hockey stick relic. I await guidance from the GC grandmaster.

EM " At the start of the Holocene temperatures rose 5C in10,000 years. That is 0.16C per 320 years.Since 1970 temperatures have risen at 0.16C per decade.

The Dye 3 Ice core showed the local mean temperature rose at least 7ºC in 50 yrs - 1.40ºC per decade
24 D-O cycles in the last glacial show temperature shifts of 15ºC on at most a centennial time scale - 1.5ºC per decade
( Dansgaard 1989). Is that enough to be called rapid temperature change?

The difference between January 2016 and February 2015 was 0.31C. That is 0.16C per fortnight.How fast do temperatures have to change before you call it rapid?"

That last comment specious - and unworthy of discussion. This morning where I live the temperature increased fro 1C to 9.5 ºC in 3 hours = 28.22ºC per fortnight - is that enough top be called rapid?

EM get serious or get off the air!

Alan Kendall,

I am one of many who did initially accept the Holy Hockey Stick of Mann. It was prepared by an Expert after all, or so we were all told.

Bosham ( near Chichester, and one of many locations where Canute or Viking Knut, is claimed to have failed to stop the rising tide) does have older cottages vulnerable to the highest tides. Whether this is a fair reflection of rising sea levels, I have no idea! I can appreciate that Bosham was an ideal harbour for Viking designed long boats. The SE corner of the UK is prone to earth tremors, and pointing to one location as 'clear proof of sea level rise caused by AGW', whilst deliberately avoiding conflicting evidence, is clear proof of desperate measures being adopted by alarmists.

I have not been to the Gower Peninsular for 30 years, and have never been to Harlech at all! I know the sites are not adjacent, and don't know the geology, but it does make the point.

I have sailed a yacht with a ferrocement hull, reinforced concrete in other words. Not the fastest, but very solid, provided ocean acidification doesn't eat it! I have swum beneath yachts in the Med to clear ropes from propellors etc. The calcium carbonate of barnacles on the hull slices through human skin very easily. I know!

The common herring (Clupea harengus) helped feed the UK, and Holland for centuries. Sun dried herring was never a good preservation option given the climate, but smoked (kipper) or brine worked well. With AGW theory, air drying in the smokey atmosphere may be viable, if they don't come out of the sea, ready pickled due to the acidity of the sea. I tend to think ocean acidification is a Clupea harengus rudus (Common herring sub-species red)

The US views the UK as it's European aircraft carrier, conveniently placed offshore. It would probably appeal to the late C de Gaulle to have the UK named after him.