Richard Cassidy commented on my UK Floods: The Crisis Deepens post yesterday, saying he saw a feature on BBC news yesterday which suggested that the Gulfstream had [temporarily??] shifted south of the UK.
Thanks for your comment Richard. I found a BBC News Online report that talks about the shifting of the Jet Stream high in the atmosphere, rather than the Gulf Stream in the waters of the North Atlantic:
[Met Office weatherman Dan Corbett] said a broad band of low pressure had been sitting across the UK, pushing the jet stream – a ribbon of fast moving air in the upper atmosphere – further south than usual, keeping high pressure and settled weather away from the UK. “In a normal summer the jet stream is to the north of the UK. This allows the Azores high to build across the UK and bring settled and more typical summer weather for the UK,” said Mr Corbett.
In my post Defeat Global Warming? Just Think About It, I referred to the Gulf Stream, rather than the Jet Stream, and commented on the fact that recent measurements indicate it has been weakening as well as exhibiting a tendency to move further south than is usual. I don’t think the Gulf Stream has shifted so far south that it’s now below the UK — but for a while it did move a little further south than its normal course earlier this year (before moving north again) and weakened somewhat at the same time.
Personally, I believe the behaviour of the two streams must be interlinked, the position and strength of one influencing the location and activity of the other, while each in turn is further influenced by other related factors such as, for example, the salinity of the North Atlantic in the case of the Gulf Stream and, regarding the Jet Stream, the barometric pressure of adjacent air masses. I’m no meteorologist — but while we all know it’s a highly complex business, it seems logical to me to accept that these two great engines driving our climate must be intimately bound together.
In another previous post, Climate Change: Sunspots? Or Us? I referred to theories that seem to indicate a cooling, rather than a warming effect might be on the cards — at least in the northern hemisphere — in the near future. Now I’ve found two reports that robustly refute that idea.
Titled Gulf Stream Shift Removed From Scientific Forecasts, The Heat Is Online carries both reports on one web page. The first report is from Associated Press on 14th June 2007 — Dropping Ice Age scenario, researchers discard Gulf Stream catastrophe scenario:
TORSHAVN, Faeroe Islands: From the deck of a research ship moored in these gusty north Atlantic islands, workers are offloading three bright orange buoys whose sonar devices will help Bogi Hansen fill more gaps in an intriguing twist on climate change forecasts.
For the past year, the Faeroese scientist’s sonar has been pinging the Gulf Stream, the warm ocean current that has kept this subpolar archipelago unfrozen for centuries. His findings are of big interest because they contradict one of the most catastrophic predictions linked to global warming: that Arctic melting will strangle the Gulf Stream, thrusting Europe into a new Ice Age.
In fact, Hansen’s research and recent climate models raise a tantalizing possibility: Can the slight weakening of the Gulf Stream expected over the next century actually help to offset the effects of global warming in northern Europe?
Some scientists think so.
The second report, from the New York Times dated 15th May 2007, is headlined Scientists Back Off Theory of a Colder Europe in a Warming World and takes us to Oslo, where:
Mainstream climatologists who have feared that global warming could have the paradoxical effect of cooling northwestern Europe or even plunging it into a small ice age have stopped worrying about that particular disaster, although it retains a vivid hold on the public imagination.
The idea, which held climate theorists in its icy grip for years, was that the North Atlantic Current, an extension of the Gulf Stream that cuts northeast across the Atlantic Ocean to bathe the high latitudes of Europe with warmish equatorial water, could shut down in a greenhouse world.
Without that warm-water current, Americans on the Eastern Seaboard would most likely feel a chill, but the suffering would be greater in Europe, where major cities lie far to the north. Britain, northern France, the Low Countries, Denmark and Norway could in theory take on Arctic aspects that only a Greenlander could love, even as the rest of the world sweltered.
All that has now been removed from the forecast. Not only is northern Europe warming, but every major climate model produced by scientists worldwide in recent years has also shown that the warming will almost certainly continue.
My original concerns about a dramatic cooling event stemmed from having read The Coming Global Superstorm by Art Bell and Whitley Strieber. The film The Day After Tomorrow was based upon this book. In it, Bell and Strieber wrote:
By definition, a superstorm would involve an entire hemisphere. Its winds would reach extreme velocities, possibly in excess of two hundred miles an hour.
The storm would be triggered by a sudden increase in Arctic temperatures at the surface — exactly the kind of warm snap that could occur at any time during the global warming scenario presently unfolding — combined with extreme cold aloft. This warm flow of air would heat an ocean surface already affected by a loss of salinity due to polar melt and runoff from Greenland. The lack of salt in the water would cause it to take on heat quickly. At that point, the flow of the North Atlantic current would suddenly change, dropping south.
When this happened, the ultracold air trapped above the arctic by the warm airflow would slide southward, with a violent outcome.
The storm would last until the ocean cooled enough for the flow of the current to be reestablished. Before that happened, there would be a massive blizzard or series of blizzards that would dump billions of tons of snow across a fifth of the earth’s surface. When the sun finally did return, the huge increase in the earth’s albedo, or reflectivity, caused by the snow, would cause a dramatic drop in temperature. Whether the ice would melt or persist across the next summer would depend on its depth. If it persisted, a cooling trend of some duration would result. There would even be a possibility that a new ice age would begin …
The evidence that long-term changes in climate do take place is irrefutable. The ice keeps coming back, and we aren’t sure why. But something acts as the trigger, and we know that this event is a sudden one.
– The Coming Global Superstorm, Whitley Strieber & Art Bell, Pocket Books, 2000, pp/102-103
Bell and Strieber’s theory was pretty much rubbished by the scientific community when the book was first published — chiefly because neither author is qualified in the fields in which the chief critics specialize, but also because no climatologist could stomach supporting a theory that proposes a world-changing event occurring over such a short space of time (the book suggests that the superstorm itself might last only a few weeks, resulting in an ice age possibly lasting thousands of years in duration). The film, though popular with the public, received more criticism from the scientific community in general, mainly because it was felt it took further liberties by compressing the superstorm time-scale into a matter of days and vastly exaggerating the ferocity of the meteorological events portrayed.
While I don’t know much about Art Bell’s bona fides, I feel I do know where Whitley Strieber’s coming from. Yes, he’s from way out in left field, as Americans would say — but I’ve read every one of his books and have been a regular visitor to his Unknown Country web site for over a decade. I believe him to be an honest reporter of the unusual and bizarre “visitor” events that have plagued him through much of his life, and that this lends veracity to the information he claims has been imparted to him regarding the perilous state of our planet. It’s upon this information that Whitley has built his theories and commentaries about climate change. Despite the two items reported above, I’ve seen nothing yet that convinces me I can now safely ignore his superstorm theory. Scientific history is littered with theories that were considered heretical nonsense at first, then cautiously applauded as ground-breaking and finally accepted, the process often taking decades.
The Superstorm theory states that the world will experience precisely the kind of warming events we’re seeing now, accompanied by increasingly violent and extreme weather events prior to a sudden change in climate from warm to cold, like a giant elastic band being stretched and stretched until it suddenly snaps back into shape with a ferocious release of pent-up energy. That the planet has experienced sudden, catastrophic changes like this in the past is not in dispute, even amongst the experts. What people can’t agree about is how those past changes were set in train and whether we’re seeing similar tell-tale markers here in the present.
Please be sure to read the comments for this post for further discussion of the Superstorm Theory.
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