phaywarduk

I have to say that the current warm SST's in the North Atlantic, the obvious strong Atlantic weather and jet stream directly over the UK do seem to throw doubt on the theory of an NAC stalll. If the stall were truly real then I think we would be witnessing some kind of signal to register the event such as a quiet Atlantic and/or a more southerly jet. But it does begin to look like business as usual regarding a warm wash of Atlantic weather systems over the coming winter months. Regards, Paul

The earlier 2005 view of a weakening NAD was challenged by later data that showed the current has an uneven flow over time. They concluded the current was as strong as ever and showed no sustained sign of slowing. This is another reason why caution is so important. This whole thing begun with a report from the Deagle research team that included one Dr Guanluigi Zangari and it has been suggested that he mistook the break away loop current in the gulf as a new phenomena whereas it happens fairly regularly. There is pelnty of room for doubt and we need more hard evidince really. Regards, Paul

Hi Richard, Tommy-rot in the internet context is positively polite. Do you have specific reasons for believing this or is it a 'gut feeling' so to speak? Regards, Paul

Great catch CH. For a minuite there I was really worried. Gratefully yours, Paul

Hi Blitzen, many thanks for the satelite update. I agree, its looking distressingly weak. The only comparison data we have was posted earlier in this thread between August '09 and these October '10 readings. That comparison is very worryihg as it seems to show an almost total collapse of the NAD velocity. However, I think we would need to see a much larger sample for proper comparison. I believe the Met office responded to a poster on another forum who presented this info as possible evidence of a stall. Their reply was to say it is not always easy to 'see' the flow velocity from satelite and simply repeated the mantra that there was no evidence of slowdown. It seemed an odd response to me but who knows. I, too think the 'wait and see' approach makes the most sense. Regards, Paul

Due to the large body of warm water drifting over from the tropics, there would probably be some SST cooling over time if the NAD does stall. The big question is how much and over what time interval. Some estimates refer to 0,5 degrees of cooling while others are outragously high at 2 to 3 degrees. There is a school of thought that suggests we would never be subject to the climate of Northern Canada or Russia because they are climates occuring within large land masses. Our climate even without the NAD would still be influenced by warmth released from the oceans in winter. There is some evidence that the NAD does directly affect the JET and as Paceboy mentions above, the effect might be for the JET to track futher south leaving us exposed to more northern continental conditions. The trouble is none of these ideas are backed up by hard science and we are unfortunately left with more speculation and questions than concrete answers. Regards, Paul

Sorry to resurrect this topic. On the whole I found the thread fascinating and thoughtful with strong attempts to analyse some of the evidence out there. I wanted to add it is unlikely a slackening of the NAC will immediately lower SST's due to the considerable body of warmth already held within the ocean. Apparently, from a theoretical point of view, a weakening of the current is more likely to have a direct effect on the jet stream. Cooling of the NAO would occur over at least a 10 year period which geologically is lightening fast. I have been speaking to a friend of mine who works in the field and there is awareness of a weakening but scientists are a very wary and conservative lot with reputation very much in mind. The preliminary data set is far too little to jump to the conclusion that the observed 'pause' in the NAD is due to anything other than natural variation in the cycles of this complex current. If the satelite imagery continues to show a stalling over the next few years and is combined with measurable cooling in the North Atlantic, then I think the stalling phenomenon will become an international issue. If I were a climatologist, the last thing I would want is to poke my head above the parapet only to be grouped with the likes of the self styled Lord or even Earl of Stirling and his crackpot ideas. Regards, Paul