From the UNIVERSITY OF LINCOLN, where they are trying to make the North Atlantic Oscillation bend to their will part of climate change.
Severe snowy weather in winter or extreme rains in summer in the UK might be influenced by warming trends in the Arctic, according to new findings.
Climate scientists from the UK and the US examined historic data of extreme weather events in the UK over the past decade and compared them with the position of the North Atlantic polar atmospheric jet steam using a measure called the North Atlantic Oscillation (NAO) index.
The NAO indicates the position of the jet stream – which is a giant current of air that broadly flows eastwards over mid-latitude regions around the globe – through a diagram which shows ‘negative’ and ‘positive’ spikes, similar to how a heart monitor looks.
The researchers highlight that the exceptionally wet UK summers of 2007 and 2012 had notably negative readings of the NAO, as did the cold, snowy winters of 2009/2010 and 2010/2011, while the exceptionally mild, wet, stormy winters experienced in 2013/2014 and 2015/2016 showed pronounced positive spikes.
The scientists also highlighted a correlation between the jet stream’s altered path over the past decade – so-called jet stream ‘waviness’ – and an increase during summer months in a phenomenon called Greenland high-pressure blocking, which represents areas of high pressure that remain nearly stationary over the Greenland region and distort the usual progression of storms across the North Atlantic.
Increased jet waviness is associated with a weakening of the jet stream, and the accompanying ‘blocking’ is linked to some of the most extreme UK seasonal weather events experienced over the past decade. The strength and path of the North Atlantic jet stream and the Greenland blocking phenomena appear to be influenced by increasing temperatures in the Arctic which have averaged at least twice the global warming rate over the past two decades, suggesting that those marked changes may be a key factor affecting extreme weather conditions over the UK, although an Arctic connection may not occur each year.
Edward Hanna, Professor of Climate Science and Meteorology at the University of Lincoln’s School of Geography, carried out the study with Dr Richard Hall, also from the University of Lincoln, and Professor James E Overland from the US National Oceanographic & Atmospheric Administration Pacific Marine Environmental Laboratory.
Professor Hanna said:
“Arctic warming may be driving recent North Atlantic atmospheric circulation changes that are linked to some of the most extreme weather events in the UK over the last decade.
“In winter, a positive North Atlantic Oscillation (NAO) is linked with a more northward, vigorous jet and mild, wet, stormy weather over the UK, while a negative NAO tends to be associated with a more southerly-positioned jet and relatively cold and dry but sometimes snowy conditions. In summer the jet stream is displaced further north, so a positive NAO is typically associated with warm dry weather, while a negative NAO often corresponds to wetter, cooler UK weather conditions.
“While part of the uneven seasonal North Atlantic Oscillation changes might be due to natural random fluctuations in atmospheric circulation, the statistically highly unusual clustering of extreme NAO values in early winter, as well as extreme high summer Greenland Blocking Index values since 2000, suggest a more sustained, systematic change in the North Atlantic atmospheric circulation that may be influenced by longer-term external factors. This includes possible influences from the tropical oceans and solar energy changes as well as the extreme warming that has recently occurred in the Arctic.
“Of course, weather is naturally chaotic, and extremes are a normal part of our highly variable UK climate, but globally there has recently been an increase in the incidence of high temperature and heavy precipitation extremes. The cold UK winter episodes we noted are not so intuitively linked to global climate change but reflect part of a long-term trend towards more variable North Atlantic atmospheric circulation from year to year during winter months, especially early winter.
“This trend has culminated in the last decade having several record negative and positive December values of the North Atlantic Oscillation, with lots of resulting disruption from extreme weather over the UK. On the other hand there has been no really notably dry, hot, sunny summer in the UK since 2006; summers overall have either been around average or exceptionally wet, and this appears to be linked with strong warming and more frequent high pressure over Greenland in the last decade.”
###
The study has been published in Weather, the magazine of the Royal Meteorological Society, where apparently “tantalising clues” is part of the science lexicon now.
Abstract
We explore a possible relation between the recent Arctic amplification of global warming and changes in North Atlantic jet stream circulation and UK extreme weather conditions over the last decade. Such a link is supported by some tantalising clues from recent North Atlantic atmospheric circulation changes in summer and winter, but due to multiple factors affecting jet stream variability, we need extended records over at least a further decade to more reliably attribute these changes to global warming.
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It seems cold is the new hot.
And when a km thick glacier inevitably bears down on Manhattan, the same mindset will be blaming the NIA (New Ice Age) on the CO2 that was emitted back in the 20’th and 21’st centuries.
It seems cold is the new hot.
Except when it’s not.
Wouldn’t it be great if nothing you ever said was held to consistency?
Joel Snider
“Wouldn’t it be great if nothing you ever said was held to consistency?”
Is that a double negative?
HotScot
January 4, 2018 at 4:16 pm
Joel Snider
“Wouldn’t it be great if nothing you ever said was held to consistency?”
Is that a double negative?
How about “Wouldn’t it be great if nothing you never said was held to consistency?”
What they are saying: we don’t really know. But we need more money to find out
“…we need extended records over at least a further decade to more reliably attribute these changes to global warming.”
One decade was not enough. But 20 years of data will be enough to reliably meet the defined goal of attributing “these changes to global warming.”
This half-assed “study” is was intended to:
1) Be published.
2) Be used for future grant request.
3) Show output for received income
And to arrive at the desired outcome – global warming is the cause.
The primary work product of the “initial” data study was drafting the proposals for “subsequent” data studies. Stacks of proposals were created, collated, and framed out to National, EU, NGO, UN, Corporate, and ECO org’s.
May, might, possible and appears.
As steef says they are guessing.
As soon as I saw ‘might be’ I stopped reading. What kind of science practices this?
Answer: political science
Same qualifiers we’ve been hearing for decades now. They all end with didn’t.
Keep it coming. Telling people that Global Warming is causing weather to be colder only increases their skepticism. But faced with the abject failure of their warming meme what else can they do? The contradictions are piling up and everyone notices. Everyone.
Oh yes, the contradictions are piling up aren’t they and it’ll only be a matter of time before one of the climate Mafioso breaks ranks and actually says so and puts his hands in the air (or, inclusively, her).
http://metro.co.uk/2018/01/02/mini-ice-age-hit-2030-save-us-global-warming-scientists-claim-7196604/
Some of the comments are funny too.
actually says so and puts his hands in the air (or, inclusively, her).
Puts “her” in the air?
This is all just bogus retrofit data masquerading as science.
Association is not cause and effect, just as correlation is not causation.
This study just caused a MILLION more eyes to glaze over. No, the glaze was not caused by the polar vortex snow BOMB!!!
Did I just read that the wet summers and wet(snowy) winters…were negative readings
….and wet winters….were positive readings
…and they actually noticed a difference?…either way, it sucked!
…doesn’t sound like “extreme” weather to me…..looks like what they always get
Trying to play weather as climate always leads to amusing contradictions.
Indeed. There’s only one system in existence: the real-time weather system. Climate is an abstraction and the concept is the subject of a lot of abuse because it’s a flawed and can’t be defended very well.
Andrew
What extreme weather?
What extreme weather?
The summer and month of April in 2012 and the summer of 2007, along with December 2010.
“On the other hand there has been no really notably dry, hot, sunny summer in the UK since 2006”..
Drought….which they would have called ‘extreme’….you can’t win
december 2010 snow cover in scotland was nothing compared to that of the early 80,s and they were playing at it compared to some years in the 70,s. all bow down to the 40,s. i have pictures from my grandfather of snow just below the top of telegraph poles. the current crop of climate “scientists” have no idea just how lucky we are with winter weather in the uk today.
I’m old enough to remember the summers of 1975 and 1976 which were very hot and dry and the winter of 1962/1963 which was freezing cold for 6 weeks with lots of snow. It will happen again. They are weather events.
Increased severity and frequency of flooding ?
Where?
We now have increased severity and frequency of clearing culverts and dredging streams just as used to happen before second rate scientists replaced knowledge accumulated over centuries with gigo computer models.
Result no flooding despite frequency and severity of precipitation comparable to those events that ruined peoples lives and homes when the idiots from half baked new universities had control.
“What extreme weather?”
From Wikipedia:
In the UK, meteorologists consider winter to be the three coldest months of December, January and February.
That extreme weather !
Let’s just run with “Unfalsifiable Hypothesis Drops 13 inches of Snow on Boston”. Everything outside of normal weather is caused by the ‘UH’ which is directly correlated to increasing CO2.
The study covered the last ten years!
Didn’t the trolls just get finished telling us that 10 years is way to short a time period to establish a climate trend?
Only if the trend is cooling. If they can make it look like the trend is warming then 10 years is plenty of time to establish a climate trend.
“recent Arctic amplification of global warming …”
More garbage in the abstract leading to garbage out from the rest of it. The author definitely doesn’t understand the implications of amplification, one of which is the requirement for an internal source of energy that boosts the output to be greater than the input. Since the input is the Sun, the internal source or energy must be something else, which can only be magical unicorn farts.
Burning my wood stove enjoying the show…..it’s been below 25 for days now and everything is frozen outside.
An excellent activity. I am also indulging and admiring my large stack of oak logs through the window. Can I recommend a glass of Penderyn or Laphroig which seems to make the experience just that much better.
Stay warm !
Ah, the good old Leapfrog (or Laphroaig a it is actually spelled…). Came across this expression some weeks ago – highly recommended:
https://www.masterofmalt.com/whiskies/laphroaig/laphroaig-px-cask-triple-matured-whisky/
Forecast windchill in Waterloo Friday night, -39 C.
Nothing like wood heat! My NG gas furnace is great but when it comes to really feeling comfy and cozy the living room with it’s fireplace in use is the place to be. And it’s not just we humans that think so. My dog and cat both think so too! When I start cleaning the ash out of the fireplace in preparation for starting a fire they’ll both be there supervising as I do it, waiting with anticipation for the results. Once the bed of coals is down and it really starts radiating heat both animals would be stretched out near it. So we got a couple of spare pet beds and put them in the vicinity and they use them. They know that our household is maintained only for their sole comfort and convenience. I swear there are times my cat is telling me to get off my ass and go make a fire. Going through some wood this cold winter.
My propane fireplace is on the blink. Not fun.
These Scientists accidentally released one of their keystone documents by mistake. I am exposing them now once and for all….
Seems to be missing something.
“Consistent with a changing climate.”
There, now it’s accurate!
SHOCK!!!
The position of the jetstream at any time has a significant effect on Britain’s weather for a short period before it moves (thereby influencing more changing weather).
Who knew?
Well, nobody apart from anyone who ever studied Britain’s constantly changing weather for maybe 5 minutes.
“increased jet waviness” made me laugh though!
If the jet stream waves, can we wave back?
Yea, but you have to go to the top of My. Washington in New Hampshire to do so. Even though that mountain is not very high as mountains go (6,289′) it is in a location where the jet stream passes over and dips down frequently. They’re forecasting -85 F wind chill at the weather station on the summit for Friday night. IMO that Mountain is one of the most dangerous because people don’t respect it due to it’s relatively low elevation but the fact is the weather at it’s summit can change even faster than it does on much higher peaks.
We still laugh about Hadley Centre’s Dr Viner prediction 15 yrs ago that snow would soon be a thing of the past (children wouldn’t know what it was). They were insisting then that the sci3nce was settled and since, a string of totally diametrically opposite forecasts to reality. They’ve doubled down on the ‘settled and still continue to play climate whack-a-moley with all the surprises they are plagued with. They’ve recently been fighting ridiculous things like current record cold in the NH with a warming arctic (it’s very cold there now) and you can walk from Texas to Kashmir right now 9n frozen ground. Oh this is just weather! We will see the Pause back in a year or two so the whack-a-moley will continue to even loftier heights.
Loons.
“Severe snowy weather in winter or extreme rains in summer in the UK might be influenced by warming trends in the Arctic, according to new findings.”
A bowl of pudding has a firmer conclusion than that!
They are correct linking some of the UK’s worst weather with Greenland blocking.
During April of 2012 Greenland blocking was in place for most of the month. That and the summer lead to what l think was one of the UK’s closest matches to the “Year without a summer” 1816. Also the bitter cold December of 2010 was set up by Greenland blocking and lead to England’s second coldest December since 1659.
I’m amused that they think they can draw any conclusions based on 10 years of data. They could have easily gone back to, say, 1910 given the sorts of things they were looking at. What a collection of knuckleheads.
The reason l think they went for 2005/15 years. Was because between 2007/12 the UK had a run of 6 cool dull and wet summers and a run of 3 cold winters 2008/11. With Greenland blocking been along with a strong southern tracking jet stream been a common theme to the cause of them.
@taxed;
That’s invoking the Texas sharpshooter fallacy. Examine the full data set, find a run that agrees with your a priori theory, extract that subset and Bingo! you have confirmed your hypothesis.
l also believe there is a link between Arctic warming and a wavy jet stream. But unlike them l think it has little to do with rising CO2 levels.
Another 10 years of data before reliable attribution can be made! Absolute clowns.
“…we need extended records over at least a further decade to more reliably attribute these changes to global warming.”
Translation : We needed at least a decade of assured income and continuing grants to really feel secure about our jobs. However 20 years would be much betterfor everyone’s sake. Think of the grandchildren.
Nice catch.
They have their conclusions all set, now they just need to sift through a pile of data to pick out the bits that support their case. This, in a nutshell, is what is wrong with Climate Science!.
Well, I am not tantalized.
What do the winters of 2009/2010, 2010/2011, and 2017/2018 have in common?
Very low solar activity. I bet they will never look into that.
Well, I for one, am highly tantalized.
On the other hand, to be tantalized can be interpreted to mean plated with Tantalum metal. Tantalum is a strong hard metal which is nearly impervious to chemical attack under ordinary conditions and has a very high melting point.
Perhaps this is what they meant?
It’s probably prone to chemical attack when the jetstream gets wavy, Every super power has a mortal weakness, Ask TantMan!
Exactly that and I did bring this up a couple of months ago in one of the threads on here. They never look into things that can’t be blamed on humans. Low solar activity increases the jet stream being meridional so we get the negative AO and NAO phases a lot more often. I even predicted this would happen and forecast a colder winter then recent years especially if La Nina stays weak or stayed neutral at the time.
Some meteorologists forecasted a colder than average winter too, like http://www.gavsweathervids.com/winter2017-18-forecast-uk.php
We can expect similar conditions for the 2019-20 winter in the NH.
Well, it is always warmer just before it turns colder.
Since nothing in the study attempts to correlate those issues with rising CO2 levels, at least there is a positive attempt to link the weather patterns with a physical causation, that being an interaction between the Jet Stream and the Arctic temperatures. That is good science. I would like to see the study expanded to include ocean temperatures and their affects on those weather/wind patterns.
“We explore a possible relation between the recent Arctic amplification of global warming “………
Thanks. So much for my speed reading.
But I do wonder if that phrase was “thrown in” merely to obtain funding, i.e. “… but due to multiple factors affecting jet stream variability, we need extended records over at least a further decade to more reliably attribute these changes to global warming.”
But, then again, I may be overly hopeful for a sound scientific investigation.
News flash, El Nino, followed by La Nina helped cool the equatorial zone allowing cold air to travel further south. My bet is the sever winters follow La Ninas because they don’t create the high-pressure systems that push the polar air back.