knocker

As I understand it this isn't about another ice age but whether global warming is affecting the the very important convergence zone south of Greenland. If so it would of course lower temps in north west Europe somewhat. The $64,000 question is this going to happen? Or indeed is happening. It creates circular discussions (elswhere in another thread where one could actually age years reading it) and in my very humble opinion you could yap about this for weeks without as yet coming up with an answer. But it certainly is a possibility.

Explanations seem to vary slightly The most prolific producer of deep water in all oceans is a region south of Greenland in the North Atlantic, where several major surface currents converge. Here, the warm salty Gulf Stream converges with the cold, not-so-salty East Greenland and West Greenland Currents. These merging surface waters sink for two reasons. First, "down" is the only place they can go. The second reason is more subtle. Because the lines of constant density on a T-S plot are curved , when waters of the same density but different temperatures and salinities are mixed, the resulting water mass is denser than either of the original waters. So the denser mixture would tend to sink even if it wasn't being forced downward by the convergence. This sinking of merging surface waters is sometimes referred to as caballing. The water mass produced by these converging currents south of Greenland is called North Atlantic Deep Water. It is produced so abundantly that it fills most of the Atlantic Ocean. The North Atlantic Deep Water flows southward beyond the equator and all the way to the Antarctic Circumpolar Current, which mixes with it to produce another water mass, called Common Water. This mixture is carried by the Antarctic Circumpolar Current around the Cape of Good Hope into the Indian Ocean, and around Australia and New Zealand the Pacific, where it fills most of these two oceans as well. Courtesy “Exploring Ocean Science†by Keith Stowe. (second edition) I think I would need some compelling evidence to convince me that the status quo is under serious threat. Edit. I should have added that as density is dependant on temperature and salinity this can't be ruled out if there is a major change in either of the latter.

I don't know if this of interest. Thermohaline Catastrophes and the Younger Dryas During the most recent ice age, the North Atlantic component of the Global Thermohaline Conveyer was partially shut down and the ocean is thought to have operated in a different mode to that of the present day. The northern North Atlantic was considerably cooler and the transport of the North Atlantic current (the northward extension of the Gulf Stream) much reduced. The North Atlantic component of the conveyer was reactivated at the end of the most recent glaciation, at about 14,000 years BP. Recent research on deep-sea sediment cores has shown that this reactivation of the conveyer was not without hiccups! Part of this conveyer stopped abruptly at about 11,000 BP -a period known as the Younger Dryas. This led to a catastrophic cooling of the North Atlantic region and caused the build up of small glaciers in the British mountains in what geographers call the Loch Lomond glacial re-advance, This cooling only appears to have lasted a few centuries, but it developed very rapidly over decades. There are several theories about what exactly led to the shut down of the conveyer. One view is that a sudden influx of fresh melt-water from the Laurentide ice sheet into the North Atlantic could have stabilised the vertical stratification and reduced the rate of formation of North Atlantic deep cold water. This, in turn, could have shut down the North Atlantic conveyor circulation, resulting in a cooling of the surface waters of the northern North Atlantic. The effect of changes in fresh water fluctuations on the thermohaline system is an example of positive feedback. The fresh water input weakens the thermohaline circulation, which makes the circulation more susceptible to further weakening. This process has been investigated in recent years using mathematical models of ocean circulation. The models show that there are a number of different states of the thermohaline circulation, some of which are stable. There are, however, transitions between stable states, which occur over periods as short as 40 years. It has been speculated that the present North Atlantic Ocean may be close to one of these transitional states, of which the Younger Dryas is an example. One study has suggested that the transition between states is not necessarily symmetrical. The change from strong to weak thermohaline circulation may be more rapid (40 years) than the re-establishment of the strong circulation (500 years). Further study of the Younger Dryas and similar events in the palaeoclimate record may give us important clues to the likely response of the present-day thermohaline circulation in the North Atlantic to global warming. (Remaining stable or flipping to another state). Source: Oceanography-an illustrated guide, C.P. Summerhayes and S.A. Thorpe. To think BP may affect the set up is to my mind laughable.

Another interesting sunset. Well I think so.

Arnold and Lenny. Arnold is a Tabby Point and Lenny a Seal Point. Lenny sadly died of some obscure lung desease.

I don't know whether it's been mentioned before but there is a pretty good web site covering the winter 62-63. I don't particularly wish to remember it as I was working on the Salisbury Plain at the time which was giving a fair imitation of the South Pole. http://www.mtullett.plus.com/1962-63/

Thought I'd better include one of South Crofty and the Roskear headframe as the latter has recently been removed so won't be seen again.

Yep. Taylor's engine house is behind Morrisons supermarket. They change hands regularly. Michell's is opposite. A view of the 90inch Cornish Beam Engine In Taylor's.

Not that far away. Marshall's is just off the main road between Beacon and Troon.

A reminder of the old days.

Thanks. It doesn't always appear to do it automatically though.

Nice set of photos Coast. I know I'm being quite thick here but how does one ensure that the attached thumbnail is reproduced in a reasonable size when clicked? As usual I'm no doubt missing the obvious.

Buff-Tip caterpillar. Sorry about the focus, they were moving plus no tripod.

Afternoon John I don't know about the 'good old days' but with hindsight they weren't so bad. I missed the move to Bracknell for which I'm truly thanful. The start of the 'bad new days'.

It is 150 years since The Times published the first reports of the weather from around Britain based on a national weather service, the forerunner of today’s Met Office. The new reports were the brainchild of Vice-Admiral Robert FitzRoy, and the following year he launched a much more daring enterprise — the first daily, public weather forecast, also published in The Times. In many ways he was ahead of his time. He soon learnt that forecasting was a thankless task — the public remembered only the predictions that went wrong, and he soon became ridiculed in quite vitriolic correspondence in the letters page of The Times. Even august bodies such as the Royal Society felt his forecasts undermined credible science. On another battlefront, FitzRoy’s superiors grew increasingly alarmed at the publicity he was attracting and the ballooning budget of what was supposed to be a modest service for reporting the weather, not forecasting it. Eventually the criticism grew so loud it led to FitzRoy’s mental collapse and suicide. In the history of meteorology, though, he is now recognised as a giant in modern weather forecasting. Of the landmarks mentioned is 1959 when the Met. Office got their first computer. I just remember this as my first job was in the Napier Shaw building at Dunstable as a general dogsbody that year. Part of the job was looking after the paper tapes that fed the Ferranti computer which made a massive 30,000 calculations a second! I believe the current computer makes 1,000 billion. Much can sure change in 50 years.

One thing that did cross my mind on posting this was how did they measure snow depths in the 19th century? I admit I don't know. It's actually still quite complicated to this day to get an accurate level snow depth as I assume many members on here realise.. Fortunately I won't see another snowboard. http://www.suite101.com/content/how-to-measure-snowfall-correctly-a78360

Normally four or five weeks but it wasn't the tea in china but a couple of guiness a day. There again the reward was we were at least supplying fairly important met. info in the early days. The reality was that in my twenty years on the ships you tended to get a hard core who stayed, for their own reasons, and the rapid turnover of the rest who were sick for much of the time. I did have one moment of weakness on one trip when we had just sailed and rounding the Mull of Kintyre we hit a force 11. The next morning I saunterd (age distorts the memory) down to breakfast, well coffee, and.......well I won't go on, sick buckets don't come into it. Guess this is not really the forum for weather ship stories. Edit. On a more serious note, with hindsight I'm amazed that nobody was seriosly injured or killed over the years.

It was indeed John. I won't go into 'sick buckets' as I'm just about to eat!

Not completely forgotten. I remember it well. We were anchored in the Clyde off of Gourock waiting to dock in Greenock. The wind started blowing a hooligan and we started dragging our anchor. No problem just pull it up and get under power. Problem was they couldn't get the anchor up and after a short while we were dangerously close to an unscheduled landing at Gourock. Eventually they decided to slip the anchor and we got under way, but it was a fairly close call. We were luckier than some other ships in the Clyde.

Similar to that mentioned by pitwood. When iron-bearing lava cools and solidifies to form igneous rock, it becomes magnetised in the direction of the Earth's magnetic field. By analyzing samples of igneous rock of different ages around the world, geologists have found that the Earth's magnetic field actually flips over and reverses direction on an irregular schedule ranging from tens of thousands to hundreds of thousands of years. Edit. Oops, missed crepuscular rays wiki. link

Apologies if this has already been covered but I got a severe headache going through previous posts. The blizzard that hit the West Country on Monday the 9th of March 1891 was arguably the worst storm suffered by Devon and Cornwall in the 19th century. Fortunately it wasn’t of long duration but in a short time created havoc and a number of people died. Some were frozen to death not far from their home but the vast majority perished at sea. For example the “Bay of Panama,†of London, a four-mast steel ship, went ashore on the 10th at Penare Point, near the Helford River with the loss of twenty lives. The storm went on to affect the rest of southern England. The following is an extract from the West Briton, Thursday the 12th. The PDF is an account of the storm taken from Symons’s monthly Meteorological Magazine. Terrific Snowstorm Railways blocked Trains embedded in the snow drifts Wrecks and loss of life Cornwall, in common with many other parts of the country has been visited this week by a terrific snow storm-a “blizzard†is the most appropriate word by which to describe it-for which no parallel can be found in the annals of recent history. All was serene on Monday morning, but within 24 hours from that time the whole of the West of England was lying under a bed of snow many feet deep in some places; railway trains were snowed up in different localities; business was paralysed; the telegraph system was little else than a complete wreck; and towns and villages were alike isolated. It is more than probable that the ravages of the storm were not confined to the western counties, but as a result of the interruption of communication by train or telegraph, the events that have transpired beyond that area since Monday evening, are as a sealed book to the people of the West. Indeed, through the same cause, we are at the time of writing in absolute ignorance as to the fate of those residing within a dozen miles of our office. Such information that has reached us points, conclusively to the fact that both in and out of the county the storm-though of brief duration-has been of excessive severity, and when the results can be catalogued they will, no doubt, represent a serious record.. The fall of snow that commenced on Monday morning, and continued with only a few brief intervals of cessation until the following evening, was one of the heaviest ever known in this part of the world, and it was accompanied by a terrific gale, which not only had the effect of materially increasing the serious results arising from such a phenomenal snow-fall, but wrought of its own accord considerable destruction and devastation. Nowhere are the effects of its ravages more clearly to be traced than on the railway, where telegraph poles have been blown down by wholesale, and the telegraphic connection between various stations reduced to chaos. In addition to this the snow was blown into such deep and solid drifts that the passage of trains became impossible, and, as a consequence, railway communication both in and with the west has been almost entirely suspended. The Great Snowstorm of March 1891.pdf

Synoptic chart and track 031200z. The other is tropical storm Fiona.

New research proposes that as many as 150 million people could be affected as ocean levels increases by 30cm to 70cm by the end of this century. This could result in flooding of low-lying coastal areas, including some of the world's largest cities. The team published the study in the journal PNAS. Scientists led by John Moore from Beijing Normal University, China, write that to combat global warming, people need to concentrate on sharply curbing greenhouse gas emissions and not rely too much on proposed geoengineering methods. http://www.bbc.co.uk/news/science-environment-11076786

GREENLAND In ]uly, researchers monitoring the ]akonshavn Isbrae glacier on Greenland's west coast saw it retreat almost l.5 kilometres in a single day, as a seven-square-kilometre section broke up. The glacier, which is thought to be the single largest contributor to sea-level rise in the northern hemisphere, has receded by ten kilometres in the past decade and its front is now further inland than at any time in its recorded history.

A new study shows the Arctic climate system may be more sensitive to greenhouse warming than previously thought, and that current levels of Earth's atmospheric carbon dioxide may be high enough to bring about significant, irreversible shifts in Arctic ecosystems. http://www.colorado.edu/news/r/7f24670acf439fcb5964c45cd85537a5.html