UV-RAY
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Posts posted by UV-RAY
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I've been musing over the effects of volcanic activity myself Fred, but I thought there would be a lag effect from the recent eruption?Just thinking that this -ve PDO continues to fuel a 'readily' -ve NAO setup and whether recent large volcanic activity may fuel northern blocking down the line. Like the La Nina played big part in winter just gone if this PDO will 'drive' summer pattern. There has been a delay of GPs thoughts and hopefully they'll come off [still no panic yet as its very early days] but I wonder what has forced this delay and looks slightly possible to continue to delay?
BFTP
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Good post TWS we certainly do need to encourage people into research LRF . No LRF is infallible the slightest change has a huge knock on effect, the key is to learn from past mistakes. GP'S LRF have proven to be very good over a consistent time, and I'm sure he will look back come September and hold his hand up IF the rest of his forecast proves to be wrong.I don't agree. I think it shows humility and adaptability if, when people get a LRF wrong, they admit to it and have a good look at the reasons why it went wrong. I also think that if a forecast is going "to plan" it is still worth giving updates every few weeks as a means of self-evaluation and reassurance to the public that the forecast hasn't yet been de-railed. This happened with GP's accurate forecast for the winter of 2010/11.
If someone issues a long-range forecast and it ends up well wide of the mark, it's not going to give the public a good impression if he/she then sticks with it for another couple of months despite the fact that it's clearly wrong. Of course the trap to avoid there is changing one's mind only for the original forecast to prove nearer the mark (which can happen, as sometimes teleconnections throw up a variable that temporarily de-rails the forecast only for the longer-term signals to prove correct, bringing the forecast back on track later on). That can end up more embarrassing even than sticking with a clearly wrong prediction.
We do need to encourage people to research into long-range forecasting as these teleconnections have proved to have predictive value but there is no such thing as a bullet-proof method of long-range forecasting and it's exceedingly unlikely that one will ever exist, such is the chaotic nature of the atmosphere. But if we can increase the probability from "random chance" to "70% accuracy" then we'll have really got somewhere.
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Have to agree with this, once the first part of the forecast is bust then how does the rest of the jigsaw fit together. GP record in LRF is better than anyone's, but looking at the SST profiles now it's really hard to see just where this heat would come from. An average summer looks the form horse too me.'shades' of 76.... imho the summer of 76 was remembered for the drought and secondly the heat. atm the southern half of the country IS very dry, it wouldnt take much of a hot spell to brown the grass off as theres no appreciable rainfall expected for these areas. ok, 76 was a countrywide affair, 11 wont be, and 76 wasnt wall to wall sun/heat, there were plenty of benign cloudy days.
it wouldnt surprise me if a pattern change to settled / hot does evolve in the next few weeks. but imho IF theres no such pattern evolving by mid july, id suggest its unlikely that one will evolve towards august.
same principal as my 'if the cold synoptics arnt in place by the end of january, its highly unlikely there will be a freeze in february'. weather patterns take time to evolve, so signes have to be there. so, ill not worry about the lack of hot summery weather until mid july, a good 5-6 weeks away, if we are stuck in the same pattern by then, thats the time to bemoan another 'summerless' summer.
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It's not a case of being against, LRF is fraught with difficulties and people just love to knock them. I take my hat off to anyone forecasting one, especially GP who puts more detail into one paragraph than most on here post in a lifetime. Personally I feel he's made the wrong call, SST profiles have changed dramatically since GP's forecast. It's still early days so lets wait until another few weeks before we put the nails in the coffinFinally, one person joins the fight against long rangers! :-)
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You really need to get out more TWS, these fantasies are unhealthy.I've mentioned in the past that if I could make whatever modifications I wanted to the British climate, I would narrow the daylight range to something in the region of 10 hours/day in midwinter to just over 14 in midsummer. Another, related, change would be to characterise winters by a stronger sun but colder airmasses.
The "rock-solid ice cover" issue (which, as mentioned earlier, has been my only significant issue with some of the recent prolonged cold spells) most commonly arises when the dewpoint creeps above zero, initiating a damp thaw (especially if rain/sleet falls on top of the snow) and then the whole lot re-freezes. Freeze-thaw mechanisms via sunshine and low dewpoints may eventually turn snow into solid ice but it takes a lot longer, as I've seen for myself during some late February/early March cold snaps in the Tyne and Wear area. Thus, if we had a climate where the sun, rather than high dewpoints, was the most common "thawing agent" we'd probably see less issues with ice.
I also have fantasies about lighter, brighter winters, and homegrown convection initiating in the sunshine during Arctic outbreaks, even in December (so no more wishbone effects to worry about etc- you'd see heavy snow showers near windward coasts to begin with and then a scattering of snow showers breaking out inland in the afternoon). Of course, some may be concerned about the sun melting the snow altogether as often happens in the UK in late February/March, but if we had colder airmasses offsetting the stronger sun that wouldn't necessarily happen in midwinter- it doesn't happen during cold snowy spells in various parts of the USA at 40 degrees north for example.
I realise that this sort of analysis is as futile as the "what would happen if the spin of the Earth was reversed?" question but we can all fantasise.
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If I was a betting man I would say the odds on a 1976 type summer coming off are 100/1. I expect summer to be similar to the previous 3, with Northern Blocking in place for much of the summer, though last years wasn't too bad.
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Well I'm still favouring a cold spring with frequent night time frost, with even the odd fall of snow thrown in for good measure. For me a warm start to June, will quickly give way to a Summer of cold and wet conditions. Northern blocking will once again be established, but with a far more active Atlantic than last year, and the jet tracking just to our South, this will lead to a very cold and wet Summer.
I for one will be quite pleased if my forecast is right, as I hate hot and humid conditions.
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The only thing I've tried to do on the model thread is pick up on specific developments and if it came off or was heading that way I would always add onto a post as per LRF...as this is what stands. Nothing ever overrode the LRF. My Feb update...nothing in the model thread has altered one iota from that...but it could well be wrong. At the end of the day Piers, what comes to stand up to scrutiny is the LRF....nothing else and that is what we are here for?
Sorry if it got your goat, but one thing I have learned is that it isn't worth doing this. And this isn't meant at all as a direct response to you but it is as a general feeling but the bitterness on this site this winter has been woeful...and it just ain't worth it mate....oh OK, well apart from your comments sometimes
It seems odd how posts I made saying that Jan didn't come out as I called it are easily and clearly forgotten. Perceptions? B)
Anyway, I will hang around to see the smacked backside this LRF deserves...
kind regards
Fred
Personally I think it's damn right rude how some have had it in for Fred, regarding his and Roger's LRF. Sure January didn't go to plan and Fred did own up too this. It appears too me that some can make outrageous comments regarding winters over post, whilst posting in a inflammatory manner, yet remain untouchable by the powers that be.
Please don't let this deter you and Roger Fred, keep up the good work!
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Anyone hoping for a hot summer better get the prozac out now, once La Nina relinquishes it's vice like grip those heights to our North will once again return. I expect a cold start to spring, a brief warm up in June, then a rinse and repeat of the last 3 summers.
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Mountain torques etc giving rise to ridging forcing warm air into the Arctic stratosphere
causing greater geopotential height anomalies causing blocking. Whether this propagates
down to the troposphere is another question.
But the way I see it is, you need the blocking in place for any warming to take place, So which is the more dominant factor, the established blocking or the warming. One needs each other?
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What I would like to know is, which comes first the blocking or the SSW. Too my untrained eye, it appears we need blocking in place for a SSW event to take place?It is a good question Mr D. It is already recognised as well that there are a series of blocking precursor conditions that are seen prior to SSW's. So in fact SSW's are more likely to be seen in blocked winters than not. In fact these blocking episodes have been well documented and assist in the wave breaking into the stratosphere that cause the warming that leads to a SSW. So there can be a thought that blocking can lead to more blocking later down the line through the assistance of a stratospheric feedback mechanism.
Having said that it is not always the case as 1977 shows.
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I'm not so sure about this to be honest, the beauty about the model thread as it stands, was that all could participate expressing a broad spectrum of views. Now it seems we have a them and us mentality, were the creme de la creme contribute on one thread, and the rest of us on another. This in my opinion will make one thread like a free for all. I'll reserve judgement until it's up and running, but hopefully I'll be proved wrong!
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I would say that it's an impossible task to say whether more are melting or increasing. As far as I know there is insufficient data to compare like for like. So we are really only speculating, which for me isn't very scientific.Ice covers 10 percent of Earth's surface and helps moderate the planet's temperature. Glaciers and ice sheets around the world are melting at an alarming rate. By keeping an eye on Earth's ice from space, NASA satellites help us understand the global effects of climate change. Skight hiccup with the video.
http://climate.nasa.gov/ClimateReel/video/Frozen_Earth_640x360.cfm
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I'm not that convinced about SSW events, for me it's equivalent to which comes first the chicken or the egg. You need height rises for SSW events to take hold, and then SSW leads to blocking. All seems a little vague too me.I think for this blocking episode it is a case of everything tropospherically and stratospherically coming together at the right time. That didn't really happen in 2009 - it was much more as if the SSW interrupted what would otherwise have been a milder pattern.
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If anyone wants to know why we have just seen the coldest two week period (last week Nov-1st week Dec) since CET records began then the answer in my opinion is below. This for me is very interesting combined with the latest model output.
http://news.bbc.co.uk/1/hi/8615789.stm
I just want to add aswell that I wasn't having a dig at you GP in the other thread. I just feel other forces are the cause at the moment making forecasting using teleconnections rather iffy. If the solar minimum is one of the causes then because of the little understanding we have on this subject makes forecasting the rest of the winter very tricky in my opinion.
Lets be honest it isn't as though we have just had a normal cold spell. We have seen record breaking temps and record breaking snowfalls and now to add to this we have seen some extremely rare synoptics in the model output.
I certainly agree with this,the last three years we have witnessed a displaced jet to our South and height rises to our North. Prior to this the Jet was moving polewards, and now it's digging south towards the equator. All this IMO, just adds confusion to to tele-connections, as any model just isn't programmed to deal with this kind of scenario. I would love to hear GP's view on this, as he is without doubt the most consistent forecaster in terms of results that I have seen.
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Found my place of solitude in here. I have no snow, and the outlook remains snowless here in Lancashire. I've never been a fan of North Easterlies and Easterlies!
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I think it's a case of some being reluctant to accept that natural forcings have, and will continue to be, the dominant factor governing our climate.I agree, I'm not in the same race as GP yet but my handicap is improving :lol: I would say RJS is though and not a biased comment from me, I believe they are in the same race and both I hold in high regard.
BFTP
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Actually I'll think you will find that the Gulf stream as moved South during the LIA. Plenty of evidence to suggest that this happened many times before.The phrase "wishful thinking" springs to mind- the Gulf Stream may or may not slow down but I think it's no trivial task to get it to "move south"!
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I can't quite make out the uk on those maps. How accurate are these?
Summer Forecast - Hot & Dry - Shades Of 1976
in Spring Weather Discussion
Posted