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Recovery in Arctic sea ice continues

Paul Hudson | 17:35 UK time, Wednesday, 21 March 2012

Arctic sea ice has staged a strong recovery in the last few weeks, reaching levels not far from normal for this time of the year.



The rise is all the more impressive, since February saw the 5th lowest ice extent since satellite records began in 1979, and until recently ice extent has been hovering close to record low levels.

Interestingly Antarctica sea ice extent is currently slightly above average, as it has been for some time.

Levels of Arctic sea ice are not just dependent on temperature levels, but local weather conditions play a huge part too.

The much publicised 2007 minimum Arctic ice level was in large part due to the prevailing wind, which blew more ice into the Atlantic - as opposed to anything directly linked to global temperatures, as widely reported in the media at the time.

Arctic weather systems are highly variable and prevailing winds can enhance, or oppose, the flow of ice into the Atlantic. Indeed the increase in ice extent this month has coincided with a change in wind direction which seems to have spread out ice cover.

It's too early to say whether this recovery will translate into higher levels of spring and summer Arctic ice compared with recent years, but scientists will be watching data closely in the coming days and weeks.

Follow me on twitter @Hudsonweather

Comments

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  • Comment number 1.

    There is seemingly little correlation between sea ice maximum and the following minimum:
    http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seaice.area.arctic.png

    There was a similar maximum back in 2010:
    http://nsidc.org/arcticseaicenews/2010/04/

    Although that one was caused by cold temperatures. If this one is caused by spreading of ice rather than cold temperatures then I suspect it will have the opposite effect - it'll thin the ice in the cold regions the ice moved from and instead put it in regions where it'll rapidly melt.

    I am going with continuation of the decline:
    http://tamino.files.wordpress.com/2011/10/predict.jpg

  • Comment number 2.

    Mr. Hudson,

    Recently there have been claims that low ice extent in the Kara Sea (north of Norway) was responsible for cold Northern Hemisphere winters. The likes of Stefan Rahmstorf claim that the exposed warm water during the winter encourages the formation of high pressure areas - thus pushing colder air south.

    But wouldn't this be a large negative feedback on global temperature? High pressure is associated with cloudless skies allowing the Arctic ocean to radiate its heat to space during the perpetual winter night while cloudy low pressure areas are pushed further south to shield the Earth from the Sun.

    I must admit to having laughed myself silly when I read Rhamstorf claiming that the phenomenon of cold NH winters "fits earlier predictions of computer models" since these same models were ascribing the opposite to global warming a few short years ago.

    Are there any plans to introduce a Nobel Prize for comedy?

  • Comment number 3.

    @2, FergalR wrote:

    “ Are there any plans to introduce a Nobel Prize for comedy? “

    I don't know if you are aware but if such an award were to be introduced then Stephan Rahmstorf would already have been a very strong contender due to his 'Rahm-smoothing'. For this he describes a method that Heath Robinson would have been proud of to produce what ultimately turns out to be a simple triangular filter. Some discussion here:

    http://climateaudit.org/2009/07/03/the-secret-of-the-rahmstorf-non-linear-trend/

  • Comment number 4.

    "I must admit to having laughed myself silly when I read Rhamstorf claiming that the phenomenon of cold NH winters "fits earlier predictions of computer models" since these same models were ascribing the opposite to global warming a few short years ago."

    What results "a few short years ago" were saying a reduction in arctic sea ice would lead to warm european winter weather?

    As far as I am aware the modeling for it's effects is only a few years old and they are showing the kind of atmospheric impact Ramstrof mentions in response.

    People in lower latitudes like us who think the loss of arctic sea ice way up there will not affect them may be rudely surprised in coming decades. This effect may be merely the tip of the iceberg so to speak. Removing a permanent cap of ice above a vast ocean at the top of the world is a step change and the impacts on evaporation, radiation, albedo, ocean circulation and weather itself could be severe.

  • Comment number 5.

    Q

  • Comment number 6.

    Quake. I laugh when people talk about man made global warming. I believed that lie until I worked for a Carbon Management company and found out it is due to natural occurring cycles over 100's of years.

  • Comment number 7.

    What are you really saying? That through working for a carbon management company you got into the inner circle of the lizard people and uncovered the truth?

    I don't see why working for a carbon management company would enlighten you at all.

    What is your actual evidence that man isn't warming the world?

  • Comment number 8.

    One feature of the Arctic this year so far is that temperatures have been above the long term average throughout: http://ocean.dmi.dk/arctic/meant80n.uk.php

    This supports the view that the relatively sudden spurt in Arctic ice build up recently has been driven by prevailing winds, and as such the ice is likely to be quite thinly spread. If so, then this ice is likely to melt away quite quickly in the next 4-6 weeks.

  • Comment number 9.

    Quake. My evidence is 1000 years of data, that you are ignoring. It was warmer here in Roman times and there was no sun spot activity through the dark ages and the Thames used to freeze over. The 170% tax on fuel should have been spent on scientific research into providing cleaner and cheaper fuel and repairing roads, not on crack brain schemes that have little benefit. What gives you the authority to think you are correct on this subject!

  • Comment number 10.

    Quake said . .
    "What are you really saying? That through working for a carbon management company you got into the inner circle of the lizard people and uncovered the truth?"

    Spilled my coffee reading that! And they say 'warmists' don't have a sense of humour.

  • Comment number 11.

    Tim: "Quake. My evidence is 1000 years of data, that you are ignoring. It was warmer here in Roman times and there was no sun spot activity through the dark ages and the Thames used to freeze over."

    That is not evidence the recent changes are natural. Just because the climate has changed naturally in the past does not mean the recent change is natural. That's a logical fallacy.

  • Comment number 12.

    There was an interesting post recently at WUWT called 'Sea Ice news volume 3' (about a week ago) which mentioned that some potentially useful data pre 1979 is still being analysed.
    It appears there was a rise in arctic sea ice in the 70s which is not generally shown in the graphs joe bloggs tends to see - I certainly wasn't aware of it. This rise does not look equal to the size of the decline since, but it does tempt one to speculate whether we might have passed a low point in summer sea ice for the time being. Note here, I'm not suggesting that a return to the mean level is likely, only that a gradual increase over the next few years is not completely impossible if a major factor is wind and ocean current flow.

    Quake's link to Tamino's graph showed another interesting thing - the data points tend to go down two steps, then up one or two, gradually describing a downward trend. For this year to be another downward step would be unusual although not unprecedented (mid 90s).

    Newdwr54 point about thinner ice being more prone to melting (more rapidly) seems perfectly reasonable. However, I'm not clear how that would necessarily effect the higher latitude ice. If ocean heat is used to melt the outer edges, would this not (to some extent) create a cool water barrier, protecting the ice further north?

  • Comment number 13.

    Posted this back in Feb, but more relevant here:

    Arctic ice interesting this year, Barents & Kara sea ice has a great deal of difficulty getting established, still not there and we are late in the freeze up season.

    Whereas the rest of the Arctic is well established and in some areas noticeably earlier than last year, especially Bering and Chukchi:-

    http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/recent365.anom.region.2.html

    Also Barrow Ice thickness at present is:1.36 m, 4 ft 5.5". This is about 30 days ahead of last year.

    http://seaice.alaska.edu/gi/observatories/barrow_sealevel

    Maybe the difference is from SSTs, North Pacific has been cooler than normal, product of a double La Nina? North Atlantic has been warmer, product of? The melt season later in the year will, as usual be of interest.

    PS, just checked and “Barrow Sea Ice Thickness and Sea Level” offline at present. Last time it was because it had been “calibrated” by some passing “poley bears”!

  • Comment number 14.

    #9 tim

    Lots of people used to work at Carbon Management companies? How is the new garrage roof? Still waiting for the foot after foot of snow?

  • Comment number 15.

    #4. - quake wrote:
    "What results "a few short years ago" were saying a reduction in arctic sea ice would lead to warm european winter weather?
    As far as I am aware the modeling for it's effects is only a few years old and they are showing the kind of atmospheric impact Ramstrof mentions in response."
    What you seem to be saying is that it is only since we have started to have colder winters that th e models have started predicting colder winters? What a coincidence! As far as I am aware, prior to the actual colder winters, there were no predictions of colder winters. If you know of any, please let us know.

  • Comment number 16.

    12. lateintheday:

    There are two 'types' of sea ice melt according to the NSIDC -'top melt' and 'bottom melt'. Without insulting anyone's intelligence, 'top melt' means melt off the surface due to surface temperature/exposure to sunlight, etc. Bottom melt is obviously caused by sea surface temperature.

    Last year I remember reading on the NSIDC that much of the spring melt was the result of 'surface melt' according to the US Navy. Unfortunately I can't find the link now. I would suggest that if temperatures remain above average during spring in the Arctic then that will be the case this year also.

    As greensand points out, SSTs have been quite low over the past few months, so I'd guess that 'bottom melt' will be slower this year initially, as it was last year.

  • Comment number 17.

    Yes, I suppose the sudden rapid spread of the ice would suggest that it could be a rather thin layer, which might quickly melt in summer - so it will indeed be interesting to watch what happens. The recent thinness of the ice seems to be as much a cause for concern as the actual spread.

    To FergalK#2

    I too have some difficulty understanding this sea ice/high pressure thing. What you say may be true. I have wondered myself why "warm" exposed water should encourage high pressure in the first place. Most of the high latitude winter anticyclones form over the coldest regions (Greenland, Siberia, N.Canada). I would have thought warm air rising from an open sea would encourage lower pressure. Explanation anyone?

    Perhaps this is a case of your and my "little knowledge being a dangerous thing". I have been caught out this way before and have learned to be very circumspect with my own meteorological theories!

  • Comment number 18.

    There's a stark contrast between this sea-ice condition and GISS's claims of record Arctic temperatures. I've been doing some digging, and think I've detected data fiddling:

    http://endisnighnot.blogspot.co.uk/ under "GISS - Strange Anomalies".

  • Comment number 19.

    Re 18. Brent Hargreaves wrote:

    you say on your blog: "I know that you wouldn't read a thermometer in London and assume that the people of Corsica and Oslo need the same clothes today as you. But that is precisely what they are doing."

    That isn't what they are doing. They are extrapolating the anomaly, not the absolute temperature. Ie if the temperature in Corsica in one month is 2 degrees warmer than average for Corsica, they extrapolate the temperature for Oslo as being 2 degrees warmer than average for Oslo.

    The GISTEMP team have already tested that anomalies correlate over long distances from available data. GISTEMP isn't trying to get the extrapolated arctic value right 100% of the time, some months it will be too warm and some too cold.

    As for February 2012, DMI also shows arctic temperature north of 80N much warmer than average and they incorporate more data than GISTEMP
    http://ocean.dmi.dk/arctic/meant80n.uk.php

    and UAH satellite record shows the North Pole above average in February too (although that's the lower atmosphere, not the surface)
    http://vortex.nsstc.uah.edu/data/msu/t2lt/uahncdc.lt

    Plus a warm arctic at this time of the year isn't necessarily at odds with a high sea ice level. It can still be in excess of 4 degrees warmer than average over a lot of the arctic at this time of year with the temperature still well below zero. It depends where the warmth is. For example GISTEMP map for Februrary shows cooler than average conditions in the Bering Sea which is where the extra ice is this year.

    Also are you sure GISS claims record arctic temperatures? Temperatures in the arctic are regularly in excess of multiple degrees these days. The GISTEMP map for February doesn't look particularly remarkable anymore.

  • Comment number 20.

    John cogger. While working for a Carbon Management company they gave me an Al Gore video to watch, the inconvenient truth, I fell asleep. I then watched the alternate view on either C4 or C5 to mock it, but one conversation with Nigel Lawson changed my whole view. Because I was selling Carbon Management, I had plenty of time to investigate on the internet and found that much evidence that it is climate change, rather than man made change. In the first 9 months of my time with a Carbon Management company I sold £90K of business, in the next three months I hardly sold any business and had to leave, because I didn't believe in it any more. The garage roof will out live what ever is throw at it then next 30/40 years, I am always 10 years ahead of the game.

  • Comment number 21.

    #20. - Tim wrote:
    "Because I was selling Carbon Management, I had plenty of time to investigate on the internet and found that much evidence that it is climate change, rather than man made change. "
    I think that you have to be careful when using the term "climate change", since it implies "man-made".
    I prefer to use the term "natural climate variability". As far as I am concerned, the only evidence is for natural variability. Unfortunately too many scientists and the media seem to assume that because something has changed over recent years, that must be due to "man-made climate change". Often we don't even know how much things have changed, as in the case with Arctic sea ice, because the detailed data don't go back far enough.

  • Comment number 22.

    Still no February Hadcrut3 or even HadSST2 figures from the MO.
    Maybe they have been spending so much time on preparing HadCRUT4 and CRUTEM3, that they have forgotten about the current series.
    This time I am not going to "chase" the MO for the data and just wait to see how long it takes this month.

  • Comment number 23.

    Quaesoveritas. :-) I will take note and use "natural climate variability" in future.

  • Comment number 24.

    #18. - Brent Hargreaves wrote:
    "There's a stark contrast between this sea-ice condition and GISS's claims of record Arctic temperatures. I've been doing some digging, and think I've detected data fiddling:
    http://endisnighnot.blogspot.co.uk/ under "GISS - Strange Anomalies"."

    Strangely, my normal link to the NASA/GISS data website doesn't seem to work any more and neither does the link to the temperature map on the above "endisnighnot" blog entry:
    http://data.giss.nasa.gov/gistemp/
    http://data.giss.nasa.gov/gistemp/maps/
    Even the following link doesn't seem to work:
    http://data.giss.nasa.gov/
    Can anyone else access these sites, or is it just me?

  • Comment number 25.

    What is 'normal' for arctic/antarctic ice cover. The area cycles over a period of approximately 80 years so what part of that cycle is 'normal'?

    In 1940 there was very little ice at the north pole at late summer, was that 'normal'? Sea ice has many inputs apart from air temperature that dictate ice area and thickness very few of which are considered by the IPCC, NASA, etc. in their drive to criminalize CO2.

  • Comment number 26.

    24. QuaesoVeritas:

    I can access them all no problem. Perhaps your nefarious intentions have been identified by some new access control security system?

  • Comment number 27.

    #26. - newdwr54 wrote:
    "I can access them all no problem. Perhaps your nefarious intentions have been identified by some new access control security system?"

    Yes, it appears so, although I haven't entered into "conspiracy theory" territory yet.
    More likely to be something my ISP has done, something similar has happened before to other sites.
    It annoys me when links which have been working perfectly for years suddenly stop working.

  • Comment number 28.

    So to conclude.........

    No warming for 14 years
    Antarctic ice coverage at above average levels
    Arctic ice coverage at normal levels
    No sign of any acceleration in sea level rise

    The alarmists dont have a lot left except bluster and a supportive government who are terrified at the possibility of losing all those green tax sourced pound notes (£40b pa and rising)

  • Comment number 29.

    What utter rubbish!
    http://www.bbc.co.uk/news/science-environment-14945773
    http://www.bbc.co.uk/news/science-environment-1714326

    Also if we were to substitute arctic ice coverage and put sales figures
    instead on the y axis and when asked my sales person came out with
    'cyclical patterns' I know what I would say and do.

  • Comment number 30.

    Utter rubbish Buckland?

    Arctic ice, rather the lack of it is the alarmists poster boy, its the bogeyman they use to frighten the weak minded into believing their guff

    Untold stories (especially in the BBC) claimed the Arctic would be ice free within the next couple of years - this satellite image that shows its at near normal levels ice-wise shows its yet another load of alarmist codswallop that has been proven to be baloney

  • Comment number 31.

    openside50: "this satellite image that shows its at near normal levels ice-wise "

    Anytime the line on the graph goes near 0 it's "near normal levels" and this happens at some point every year:
    http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/sea.ice.anomaly.timeseries.jpg

    But it's happening less and less often because the overall trend is downwards.

  • Comment number 32.

    It's easier to see on this graph:
    http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seaice.anomaly.arctic.png

    Notice that arctic sea ice in March/April 2008, 2009 and 2010 were all "near normal" too.

  • Comment number 33.

    Not buying it Quake

    As Paul said above, Antarctic ice coverage has been increasing for decade, there has been no statistically significant increase in global warming for 14 years and here we have proof that the long predicted collapse in Arctic ice is baloney

    We had been told it would be ice free by 2013-2015

    The alarmists predictions made in the past are one by one being shown to be devoid of substance

    Where is the warming?

  • Comment number 34.

    Well put Mr quake. Your graph explains the position very well. Weak minded
    are for the people who dont face up to the reality and will grasp at any straw.
    Fortunately there are people who are now realising that we could be in a difficult
    situation and are for example putting excellent plans to capture carbon at Drax and a new
    power station at Grangemouth. Electricity may have to be a bit more expensive.
    So be it.

  • Comment number 35.

    28. openside50 wrote:

    "So to conclude.........

    No warming for 14 years"

    - Warming of +0.11 C/decade since 1998 according to NASA: http://www.woodfortrees.org/plot/gistemp/from:1998/plot/gistemp/from:1998/trend

    "Antarctic ice coverage at above average levels"

    - Sea ice only. Ice loss from the Antarctic land mass itself has accelerated over the last 20 years and is exceeding IPCC estimates according to research published last month in the JGR: http://www.agu.org/pubs/crossref/2011/2011GL046583.shtml

    "Arctic ice coverage at normal levels"

    - Arctic ice coverage currently 367,000 km2 (an area larger than Germany) below the 1979-2008 average according to the University of Illinois: http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seaice.anomaly.arctic.png

    "No sign of any acceleration in sea level rise"

    - Average sea level rose at a rate of ~ 1.7 +/- 0.3 mm/year between 1950-2009 and at ~ 3.3 +/- 0.4 mm/year between 1993-2009 according to research published in the journal Science in 2010: http://www.sciencemag.org/content/328/5985/1517.abstract So measured over appropriate time scales sea level rise is accelerating.

    Apart from that everything else you said was right.

  • Comment number 36.

    Nice bit of cherry picking newdwr

    Hadrcrut 3 and even Hadcrut4 which of course found warning from somewhere (they always do) show no statistically significant warming since 1998

    you gloss over that fact that Antarctic ice is expanding

    disregard the alarmist predictions about Arctic becoming ice free

    then try and claim sea level rises are accelerating when the worlds foremost experts claim otherwise

  • Comment number 37.

    Adrian Buckland - before you go ramping up my electricity bill, can you tell me what percentage of atmospheric CO2 is attributed to power stations as opposed to other sources both natural and man made? Can you tell me theoretically, what the net effect on temps a totally 'green' power supply would be. Please stick to electricity generation here.

  • Comment number 38.

    So you're seriously disputing what those Arctic ice graphs are showing?
    Seriously??!!

    And you are aware of what is happening on the Antarctic peninsula?
    Seriously you are aware?

    And you are going to deny this statement from NOAA?
    http://oceanservice.noaa.gov/facts/sealevel.html

  • Comment number 39.

    38.Buckland

    new satellite methods for measuring sea level show acceleration?

    odd how they choose which method is best suited and also odd how those methods always suit their cause

    for instance they ignored satellite temp measurements initially as they didnt show warming, nothing a bit if adjustment couldnt put right of course with once again the correction always ending up with more warming

    the old fashioned method of measuring sea levels do not show any acceleration

    http://www.google.co.uk/imgres?imgurl=http://www.worldclimatereport.com/wp-images/sea_level_update_fig2.JPG&imgrefurl=http://www.worldclimatereport.com/index.php/2008/05/06/slower-sea-level-rise/&h=351&w=493&sz=17&tbnid=nn2RU37WUiYi3M:&tbnh=90&tbnw=126&prev=/search%3Fq%3Dglobal%2Bsea%2Blevel%2Brises%26tbm%3Disch%26tbo%3Du&zoom=1&q=global+sea+level+rises&docid=92fz6QEk1jnSkM&hl=en&sa=X&ei=jZ1sT7mFNsqa0QWduLS6Bg&ved=0CEUQ9QEwAg&dur=3038

  • Comment number 40.

    So before considering a riposte on sea level rise which I'm not
    professing to be an expert on but which I would think NOAA are far
    more expert than you are. You do now accept that those graphs show a significant overall average drop in Arctic ice because if you dont there is a fundamental
    disagreement between what you see and everybody else is seeing.

    You do now accept that there have been some significant changes in the Antarctic peninsula and also now in Greenland (since 1998). If you dont I urgently suggest you watch the last part of David Attenborough's much acclaimed Frozen Planet.

  • Comment number 41.

    In my earlier post @12 I referred to an article showing arctic sea ice from the early seventies. The graph is from page 224 of IPCC FAR WG1.
    http://wattsupwiththat.com/2012/03/18/sea-ice-news-volume-3-2

    You can clearly see how sea ice peaked around 1979 - just when all of the newer graphs based on sat data start.

    There's an interesting argument near the bottom of the comments with regard to the reliability of much older data and reconstructions. Look for Julienne Stroeve, Tom Curtis and KD Knoebel.

    Instinctively, one might expect sea ice to retreat in a warmer world. However, it would not be surprising if there was a cyclical component in play also.

  • Comment number 42.

    #38. - Adrian Buckland wrote:
    "And you are going to deny this statement from NOAA?
    http://oceanservice.noaa.gov/facts/sealevel.html"

    Which statement in particular?
    The page makes several different predictions regarding future sea level rise, the fastest rate being 3mm/year, or 0.3 metres in 100 years.
    The page also shows a link to a movie, (which I don't seem to be able to run), which shows the effect of a 150 metre rise in sea level, but a visit to the Science On a Sphere page reveals that the animation starts with the sea level 150 metres BELOW the current level and rising to 80 metres ABOVE the current level.
    Why does the movie start 150 metres below current sea levels? Is it attempting to give the impression that sea levels are going rise 150 metres, 80 metres or 230 metres?
    Even if the Antarctic and Greenland ice sheets melted completely, sea level would rise by only 70 metres, and as far as I am aware NOBODY is predicting that is going to happen in the next 100 years, so what is the point of the movie?
    Even the IPCC AR4 only predicts a sea level rise of 10-23 inches (about 250 to 580mm) for high emission scenarios, so again, what is the point of a movie which shows the effect of an 80 metre sea level rise or even the one showing the effect of a 6 metre rise?
    Since the AR4 estimate is presumably based on the maximum rise in temperatures, and since temperatures have not so far risen by anything near the predicted amounts, there is little reason to believe the high emission scenario sea level rise prediction.

  • Comment number 43.

    #40. - Adrian Buckland wrote:
    "If you dont I urgently suggest you watch the last part of David Attenborough's much acclaimed Frozen Planet."
    Remind me, was that the part in which they faked the mother Polar Bear giving birth under the snow, or was it the part in which Attenbourough claimed to be at the North Pole, when he wasn't?

  • Comment number 44.

    A while back, I asked Willis Eschenbach whether he thought the GIA 0.3mm would alter the sea level trend - he thought it would. As I understand it, this 0.3mm gets added year on year irrespective of observed changes. Therefore, in ten years time we shall have a 3mm rise showing in the data even if there is no observed change.

  • Comment number 45.

    36. openside50 wrote:

    "Nice bit of cherry picking newdwr"

    You made four definite statements each of which I rebutted by referencing peer reviewed scientific literature and now you accuse me of cherry-picking?

    I see you have amended your initial statement from "no warming for 14 years" to "no statistically significant warming" and that it is now confined to HadCRUT rather than any of the other available data sets (including UAH) that show warming since 1998.

    "you gloss over that fact that Antarctic ice is expanding"

    I agreed that Antarctic *sea ice* is expanding. I pointed out that the Antarctic *ice sheet* is losing mass at an accelerating rate. A rate that is faster than that projected by the IPCC. It is the loss from the ice sheet that is important, because it is this water that contributes to sea level rise. The entire extent of the Antarctic and Arctic sea ice could melt and it wouldn't raise sea levels by a millimetre.

    You then suggest that I was trying to "claim sea level rises are accelerating when the worlds foremost experts claim otherwise"

    I quoted the findings of a peer reviewed scientific paper that demonstrated that over reasonable time periods sea level rise *has* accelerated. I linked to the paper so that you could read the abstract. In response you make the vague claim that "the worlds foremost experts" disagree with this.

    Who are these experts? Name them. Summarise what they are saying and link to their peer reviewed papers please. That's what I did to support my claims.

  • Comment number 46.

    41. lateintheday wrote:

    "You can clearly see how sea ice peaked around 1979 - just when all of the newer graphs based on sat data start."

    But if you scan on down you'll see where WUWT (to their credit) have joined the pre 1979 data onto the instrument period.

    http://wattsupwiththat.files.wordpress.com/2012/03/arctic_sea_ice_1971-2012_c2day_and_ipcc.png

    As you can see, there is no comparison between the pre 1979 data (which is highly uncertain anyway) and the decline accurately observed since at least 2005 onward.

    The WUWT commentary calls this 'cyclical' but it clearly isn't - not even if you close one eye and squint with the other. Each one of those horizontal grid lines represents one million km2 of sea ice (about the area of Egypt).

  • Comment number 47.

    there's an interactive chart for Arctic sea ice area here:
    http://arctic.atmos.uiuc.edu/cryosphere/arctic.sea.ice.interactive.html

    You can add/remove years by clicking on the labels in the legend.

    Paul mentions that 2007 minimum was in large part due to the prevailing wind. Even though the 2007 minimum hasn't yet been exceeded, 2008, 2010 and 2011 reached similar lows (compared with years between 2000 and 2006) without such prevailing winds. The minimums in 2007-2011 form a cluster about 20-25% below the minimums of 2000-2006.

    Another notable development in recent years is during July. If you plot all years up to 2007 you can see 2007 starts diverging downwards away from the pack at about day 180. 2008 and 2009 didn't have this feature even though their minimums reached quite low. But 2010 and 2011 both had such a downwards divergence starting in July. Is that just a coincidence?

  • Comment number 48.

    newdwr54 - I read the article closely and all of the associated comments. They make a joke out of combining the two data sets along the lines of . . if they can do this to the temp series then . . .
    Nice to see that you consider the older records highly uncertain - presumably that means we can't draw any conclusions over the cause of the decline. Especially since as you say, 2005 only gives us 6 years rather than the 30 yrs you prefer.

  • Comment number 49.

    newdr54

    you claim that I confine my claim of 'no warming since 1998' to hadrcrut - yet the link you gave

    http://www.woodfortrees.org/plot/gistemp/from:1998/plot/gistemp/from:1998/trend

    is so obviously an example of cherry picking that I blanch at your 'front' doing so

    I would ask others to follow that link, then look at your choice and compare it to the other options available, namely UAH, RSS and Hadcrut3

    the reason for your pick will then become obvious - its the warmest

  • Comment number 50.

  • Comment number 51.

    lateintheday

    its their speciality - data from the past is undeniable when it suits - tree rings/hockey stick/lets forget divergence

    dodgy when it dosnt - anything thats shows Arctic ice coverage less than desired from previous observations

  • Comment number 52.

    49. openside50 wrote:

    "the reason for your pick will then become obvious - its the warmest"

    I remind you that my post and link were in response to your definite statement @ 28:

    "No warming for 14 years"

    NASA shows warming over 14 years.

    UAH shows warming over 14 years: http://www.woodfortrees.org/plot/uah/from:1998/plot/uah/from:1998/trend

    NCDC shows warming over 14 years.

    Your statement @28 is wrong.

  • Comment number 53.

    AMSU ch.5 has tentatively (to the tune of 5/1,000 of a degree) poked its nose into 'above average' territory for March.

    This is the first time in 2012 that a daily temperature in ch. 5 has been above the 2003-2011 average. (Assumes my calculations are correct - QV will no doubt correct me if not.)

  • Comment number 54.

    48. lateintheday wrote:

    "Nice to see that you consider the older records highly uncertain - presumably that means we can't draw any conclusions over the cause of the decline. Especially since as you say, 2005 only gives us 6 years rather than the 30 yrs you prefer."

    The 30 years is there in the chart. There's no mystery or sleight of hand. The instrument record of minimum Arctic sea ice extent is pretty unequivocal.

    http://nsidc.org/images/arcticseaicenews/20111004_Figure3.png

    The Arctic sea ice is melting.

    That's a problem.

  • Comment number 55.

    Arctic ice is melting and thats a problem?

    Antarctic ice is increasing and according to you thats also a problem

    Decreasing - its global warming
    Increasing - its global warming
    Anywhere in between - its global warming

  • Comment number 56.

    52.newdr

    UAH shows warming over 14 years?
    http://www.woodfortrees.org/plot/uah/from:1998/plot/uah/from:1998/trend

    really?

  • Comment number 57.

    newdwr54 - you're talking in circles.

    At @45 you said . . .
    "The entire extent of the Antarctic and Arctic sea ice could melt and it wouldn't raise sea levels by a millimetre."

    Then at 54 you said . . .
    "The Arctic sea ice is melting.
    That's a problem."

    It can't be both - please make your mind up.

  • Comment number 58.

    @56 Openside50

    Which way is the green trend line going? Up? Down?

  • Comment number 59.

    #53. - newdwr54 wrote:
    "AMSU ch.5 has tentatively (to the tune of 5/1,000 of a degree) poked its nose into 'above average' territory for March.
    This is the first time in 2012 that a daily temperature in ch. 5 has been above the 2003-2011 average. (Assumes my calculations are correct - QV will no doubt correct me if not.)"
    Yes, I agree with you that this is the first time ch5 has been above the 2003-2011 average, although the figure has been above the average originally published on the discover website for a couple of days and for a couple of days earlier in March.
    The ch5 temp has been rising, with the odd daily exception, for about 1 month now, as would be expected at this time of year, but much faster than normal and faster than in 2011. At the moment the cumulative temp. for 2012 is still below 2011, but it may catch up by early April if this rise continues.

  • Comment number 60.

    #40 Mr Buckland thinks that the final episode of Frozen Planet told the truth. Think on. This episode was the one rejected by other media groups like Discivery as being too activist and not following observed data but models. Sir David only reads a script written by some BBC climate activist like R.Black.

    As far as sea levels are concerned read the reports/research by Prof Nils Axil Morner who certainly knows more about this subject than NASA/NOAA. He reports to governments though not all his reports get published for citizens, the Maldivians being a case in point. The latest sea level data shows that levels have fallen by 5mm probably due to thermal contraction but there are many causes of sea level change than temperature and very few are factored into the IPCC models which is why their sea level forecasts are wrong.

  • Comment number 61.

    "As far as sea levels are concerned read the reports/research by Prof Nils Axil Morner who certainly knows more about this subject than NASA/NOAA."

    I disagree. I don't think he's taken seriously.

    Look at how he argues sea level hasn't risen - by tilting a graph of satellite measurements that show sea level has risen.
    http://www.skepticalscience.com/pics/Moncktonsnapshot3.png

    Seriously.

  • Comment number 62.

    #61. - quake wrote:
    "I disagree. I don't think he's taken seriously.
    Look at how he argues sea level hasn't risen - by tilting a graph of satellite measurements that show sea level has risen."

    Aren't you confusing Monckton with Morner?

  • Comment number 63.

    #60. - John Marshall wrote:
    "This episode was the one rejected by other media groups like Discivery as being too activist and not following observed data but models. Sir David only reads a script written by some BBC climate activist like R.Black."
    I wasn't aware that there had been any criticism of the episode by others, such as "Discovery", but I think the following has been overlooked.
    In the episode, Attenborough states the following in the commentary:
    "I had a chance to see the changing ice conditions for myself, when I visited the North Pole. I flew with the team to a temporary camp, that is set up every year in the centre of the frozen Arctic Ocean, to support expeditions to the Pole.
    I had never visited the North Pole before, so this was a great highlight for me.
    But it was hard going in temperatures of minus 40, so as soon as filming was finished, we flew South. Little did we know that we had made it out just in time."
    Then, to camera, he goes on:
    "We got back from the Pole camp last night, and I have just bumped into the Russian commander, who has just heard from the camp, and the news is that a little crack which I had seen in the ice between our tent and the airstrip, which was no more than an inch or so wide, has overnight widened to 20 metres.
    Temporary breakups caused by stormy weather and strong winds have happened before, but they've been getting more and more frequent over recent years, as the ice has got weaker. It was only swift action by the staff that prevented a lot of valuable equipment going in the drink. The biggest concern was that the ice airstrip might break apart, but luckily it held and everyone was able to evacuate when the weather approved."
    It isn't entirely clear from the programme itself, but it seems to me that the temporary camp referred to was actually "Camp Barneo", for which there is the following Wikepedia entry:
    http://en.wikipedia.org/wiki/Barneo
    It states in this article that this is a temporary camp which is established on an "ice floe relatively close to the pole", and not at the pole itself.
    I therefore think that the impression given in the programme that Attenborough visited the actual pole, may be misleading. Also, since the camp is on an "ice floe", it is perhaps not surprising that a crack developed and since these camps have only been established since 2002, it may be slightly misleading to say that such cracks are getting more frequent.

  • Comment number 64.

    QV,

    Attenborough says:

    "I flew to a Russian camp, set up on the sea ice 70 miles south of the Pole. After several days of bad weather, we took off again, this time in a helicopter and flew across the frozen Arctic Ocean to land on the ice at the geographic Pole."

    http://www.radiotimes.com/news/2011-12-07/frozen-planet-david-attenborough-on-global-warming

  • Comment number 65.

    57. lateintheday wrote:

    At @45 you said . . .
    "The entire extent of the Antarctic and Arctic sea ice could melt and it wouldn't raise sea levels by a millimetre."

    Then at 54 you said . . .
    "The Arctic sea ice is melting.
    That's a problem."

    It can't be both - please make your mind up.
    _______________________________________________

    What exactly is the contradiction? Sea ice melt, whether in the Arctic or Antarctic does not contribute to sea level rise. However if the Arctic sea ice melted it would lead to other very serious consequences. See here under "Why is Arctic sea ice so important?": http://nsidc.org/asina/2008_faq.html

    Melting of the Antarctic ice sheets (the land-based glaciers) does contribute to sea level rise and it is occurring at an accelerating rate: http://www.agu.org/pubs/crossref/2011/2011GL046583.shtml

    So I'm afraid it *can* be both.

  • Comment number 66.

    #64. - newdwr54 wrote:
    "Attenborough says:
    "I flew to a Russian camp, set up on the sea ice 70 miles south of the Pole. After several days of bad weather, we took off again, this time in a helicopter and flew across the frozen Arctic Ocean to land on the ice at the geographic Pole.""

    Thanks for that, I hadn't seen it.
    He may have said that in the article, but not on the programme.
    I still think it isn't entirely clear whether the crack was at the Russian camp, or at the pole, i.e. did he stay overnight at the N. Pole?

  • Comment number 67.

    @66 QuaesoVeritas

    I think North Pole is one of those terms that get used quite losely. It's used all the time to describe a vast area rather than the actual specific point.

    (same for the submarines surfacing at the pole...)

  • Comment number 68.

    #67. - john_cogger wrote:
    "I think North Pole is one of those terms that get used quite losely. It's used all the time to describe a vast area rather than the actual specific point."
    There is also ambiguity over the geographic N. Pole and the magnetic N. Pole, but I don't think that applies in this case.
    If you are making claims, as Attenborough was, that unusual cracks were appearing at the N.Pole, there has to be no ambiguity. Also, how do we know that the mere presence of people and aircraft, wasn't making the cracks worse?

  • Comment number 69.

    @68 QuaesoVeritas

    Attenborough will no doubt be basing his statement on info from the guys at the camp, who go there year after year (decades of experience). If the guys on the ground are saying 'hang on, somethings not right' should we ignore them?

  • Comment number 70.

    #69. - john_cogger wrote:
    "Attenborough will no doubt be basing his statement on info from the guys at the camp, who go there year after year (decades of experience). If the guys on the ground are saying 'hang on, somethings not right' should we ignore them?"
    I am not really questioning the fact that there were cracks, just the precise location. I don't think it is clear from the programme or the R.T. article, precisely where the cracks were. Was it at the Russian camp, 70 miles south of the pole, 70 miles south of the pole, or actually at the pole?
    Anyway, as I said, they have only being going there since 2002.
    In any case, as far as I am concerned, the polar ice has been retreating since the last ice age. I would expect that the rate of ice melt would increase as the volume reduced. 20000 years ago, Britain was covered in ice, miles thick. Was it a good thing or a bad thing that melted?

  • Comment number 71.

    Sorry for the duplication in the last post.

  • Comment number 72.

    Nothing like Arctic sea ice to warm up a climate blog! Roll on 15th Sept (or thereabouts).

    However maybe there are a few more imminent happenings going on in warmer climes? A few weeks ago the following BOM statement “La Niña nears its end” was a very apt description and will eventually be proved to be correct, but when?

    Have the “signs” changed over the last 2 weeks?

    SSTs at minus 3.02c in Nino 1&2 area http://weather.unisys.com/surface/sst_anom.gif

    2 weeks ago the same source had Nino 1&2 area SSTs at circa +2c.

    30 day SOI on the way up http://www.bom.gov.au/climate/enso/monitoring/soi30.png

    Subsurface shows warm water retreating at both at 180deg and 100w (surface) http://www.bom.gov.au/cgi-bin/oceanography/wrap_ocean_analysis.pl?id=IDYOC007&year=2012&month=03

    There is no doubt that the present La Nina is nearing its end the question is when? The above have surprised, especially the time period, just a few weeks.

    Time will tell if this continues or just turns out to be a blip.

    Also Reynolds shows global SSTs have retreated from their recent peak:-
    http://nomad1.ncep.noaa.gov/cgi-bin/pdisp_sst.sh?ctlfile=oiv2.ctl&ptype=ts&var=ssta&level=1&op1=none&op2=none&day=03&month=jan&year=2011&fday=14&fmonth=mar&fyear=2012&lat0=-90&lat1=90&lon0=-180&lon1=180&plotsize=800x600&title=&dir=

  • Comment number 73.

    72. greensand:

    Yup, 'the La Nina that wouldn't die'... sounds like the title of a 1950's B-movie.

    At the latest count we are still officially in ENSO-neutral conditions, but the upturn took a downturn over the past fortnight.

    Allowing that a return to La Nina values would be a game changer, as it stands at present AMSU Ch 5 suggests that global temperatures may have responded rapidly to the rise in Pacific SSTs. If so, then this duplicates the pattern that was observed last year around this time.

    It's a tough call, but it wouldn't be too surprising if March 2012 shows a similar upswing to that seen in March 2011 in the UAH global temp data. In any case, I suspect that March 2012 will be through the roof in USA48, if news and weather reports from the US lately are anything to go by.

  • Comment number 74.

    Hi DW, just waiting to watch the "druids" being put to the "toffee sword"

    So what is a "USA48"?

    PS, "at present AMSU Ch 5 suggests that global temperatures may have responded rapidly to the rise in Pacific SSTs." Just what rises are you refering to?

  • Comment number 75.

    USA48 - guessing it's contiguous states?

  • Comment number 76.

    75. lateintheday:

    i only recognise 3 states, awake, asleep, indoors, all others tend to present problems outwith my comprehension

  • Comment number 77.

    73.newdwr54 wrote:

    "Yup, 'the La Nina that wouldn't die'"

    DW you might just have coined a new phrase 'the La Nina that wouldn't die'.

    PS, I doubt my 2 week view could possible usurp the world’s mega predictive models, but for a week or two I will watch with interest!

    Have fun!

  • Comment number 78.

    #73. - newdwr54 wrote:
    "It's a tough call, but it wouldn't be too surprising if March 2012 shows a similar upswing to that seen in March 2011 in the UAH global temp data. In any case, I suspect that March 2012 will be through the roof in USA48, if news and weather reports from the US lately are anything to go by."
    I think that most of the increase last year was in early April, and then again from mid April to mid May.
    Is the warm weather in the USA not the result of the same jetstream position which is currently causing mild weather in the UK?
    We all know that the USA accounts for a very small part of global temperatures, especially when it is cold!

  • Comment number 79.

    "Game changer", at least the natural ENSO cycle is gaining the attention that is due now in the blogosphere, and before anyone starts down the road of short term natural cycles against long term linear change please provide the perceived source of ENSO change and the timescales involved.

  • Comment number 80.

    74. greensand wrote:

    "So what is a "USA48"?"

    Sorry GS: it's UAH-speak for the US 'lower 48' states. It has its own column in their published monthly data: http://vortex.nsstc.uah.edu/data/msu/t2lt/uahncdc.lt

    Re: "Just what rises are you referring to?"

    It's just a relative rise I suppose, but average March temps in ch. 5 to date are now slightly above the 2003-2011 average for the same period. First time this year that has happened.

  • Comment number 81.

    78. QuaesoVeritas:

    "I think that most of the increase last year was in early April, and then again from mid April to mid May."

    Yes you're right QV - I got my March and April mixed up. March this year, to date, has been quite a bit warmer than in 2011. It's currently a little below, but closest to and apparently gaining on March 2009 in ch. 5, which panned out at +0.09 in UAH. what chance a positive UAH value for March 2012?

    "Is the warm weather in the USA not the result of the same jetstream position which is currently causing mild weather in the UK?"

    Probably is, directly; but what has caused the jetstream to push so far north?

    "We all know that the USA accounts for a very small part of global temperatures, especially when it is cold!"

    Lower 48 states of the US is ~ 1.6% of global surface area, but don't mention this to an American.

  • Comment number 82.

    #81. - newdwr54 wrote:
    "what chance a positive UAH value for March 2012?"
    I would have thought that was highly probable but the actual figure will depend
    upon whether or not there is a downturn or if it continues to rise. I estimate that even if there is no further rise, the UAH figure would be abouit +0.13c

    "Probably is, directly; but what has caused the jetstream to push so far north?"
    I don't know but I thought that the pattern of the jetstream each year was more or less random. If it stays in this pattern, it could be a very warm summer in the UK.

  • Comment number 83.

    Is this real?????????????

    http://www.real-science.com/crutemp4-takes-climate-bs-to-new-levels

    "They calculated the southern hemisphere land temperature (within 0.001 degrees) based on a single thermometer in South America. In fact, it was the only thermometer south of Cuba."

    If it is true I would say there may be some doubt in the credibility of met office historical data.

  • Comment number 84.

    @83 mjmwhite

    The one thermometer is from 1851. The CRUTEM4 starts in 1856, probably for this very reason. Also look at the error bars, pretty big because data from the SH is so sparse.

    The historical data is fine, you may question the extrapolations from that data but it's been shown time and again statistically to be pretty robust.

  • Comment number 85.

    This weekend already brings back memories of '76, misty mornings and hazy lazy sunny days.

    Nice press release, http://www.metoffice.gov.uk/news/releases/archive/2012/hadcrut-updates 0.068C/decade indicated rise +/- 0.1C uncertainty.

    Must be time for some policy statements that temperature isn't the primary indicator of severe climate change. Lets see what else could be used, Artic sea ice flooding, drought, ocean acidification, still plenty of opportunity to fuel the gravy train. http://www.planetunderpressure2012.net/index.asp

    'This session will make the case for a new, holistic thinking paradigm that allows space for multiple scientific, artistic and cultural discourses to achieve the vision of a sustainable world. It will be fun, energetic and participatory but will be based on the message that novel thinkers are needed to provide transformatory ideas to address global environmental challenges.'
    http://nofrakkingconsensus.com/2012/03/24/the-royal-societys-blatherfest/

  • Comment number 86.

    85. ukpahonta wrote:

    "...0.068C/decade indicated rise +/- 0.1C uncertainty."

    Where do you get those figures and what do they apply to? Annual values for HadCRUT3 were given as ~ +/- 0.05°C from 1951.

    The rate of rise (according to UAH satellite data) is +0.16 over the past 30 years, which suggests acceleration.

  • Comment number 87.

    New record high March temperature set for Scotland: http://www.bbc.co.uk/news/uk-scotland-north-east-orkney-shetland-17506257

    Northern Ireland can't be too far behind today either, given the day we've had. A nice drive through the sunny Glens of Antrim listening to Rangers tanking Celtic... For some reason I can't get Lou Reed's 'It's Just a Perfect Day' out of my mind.

  • Comment number 88.

    @ 86.

    Final sentence should read "The rate of rise (according to UAH satellite data) is *+0.16 C/decade* over the past 30 years".

  • Comment number 89.

    #87. - newdwr54 wrote:
    "New record high March temperature set for Scotland"

    I'm not certain, but all of the locations seem to be on the NE side of the country, which is not what I would have expected. I would have expected the SW, but maybe even though there is the benefit of the gulf stream on the W side, it must be sunnier on the E side.

  • Comment number 90.

    Paul Hudson wrote : "In fact The Met Office issued a press release to that end, saying the loss of sea ice that year had been wrongly attributed to global warming."


    Do you (or anyone else) have a link to that ?

    I ask because the closest I have seen says, among other things :

    "At the time it was widely reported that this was caused by man-made climate change and that the rate of decline of summer sea ice was increasing.

    Analysis of the 2007 summer sea-ice minimum has subsequently shown that this was due, in part, to unusual weather patterns.

    The high variability has made it difficult to attribute the observed trend to man-made emissions of greenhouse gases, although there is now enough data to detect a human signal in the 30-year trend. The trend and observed variability, including the minimum extent observed in 2007, is consistent with climate modelling from the Met Office."
    http://www.metoffice.gov.uk/news/releases/archive/2009/sea-ice-decline

    If there is another statement from them which shows them stating that this was "wrongly attributed to global warming", I would like to see it.
    If there isn't such a statement, this post should be amended to give the correct information.

  • Comment number 91.

    QV#89
    Due to "Fohn effect"? It is surprisingly common for Aberdeenshire and the Moray Firth area to be the warmest parts of the UK, particularly in the winter half of the year. It has occured a number of times recently.

    Fohn also occurs on N. Wales coast quite commonly, in lee of Snowdonia and to a lesser extent over the Pennines.

    Regards

  • Comment number 92.

    #91. - jkiller56 wrote:
    "Due to "Fohn effect"? It is surprisingly common for Aberdeenshire and the Moray Firth area to be the warmest parts of the UK, particularly in the winter half of the year. It has occured a number of times recently."
    Ah, I had forgotten about that. It was also involved in record temperatures earlier this year but I haven't seen it mentioned this month. Of course, it couldn't be the amount of sunshine, since it has been sunny over the whole country.
    I also notice that there don't seem to have been any new records set in England so far, which surprises me slightly. Maybe it's due to the low cloud/fog which has been around on some of the Eastern side.

  • Comment number 93.

    #63 QV--- Yes very exciting stuff worth any Hollywood script like 'Day after Tomorrow'. were we told when Sir Richard was on this perilous bit of Arctic ice? No but we do know it was sometine during the summer period when a lot of Arctic ice melts, get blown around the Arctic Ocean etc. If you think that for one moment the life of this gentleman was at risk then then you think that the BBC ignores H&S instructions. Pictures and video can prove whatever you wish but if the data is inspected then it is obvious that the Arctic is in a cyclic system. 2007 was the bottom of the cycle and now the ice is increasing. Honest.

  • Comment number 94.

    #90. - JMURPHY wrote:
    "Do you (or anyone else) have a link to that ?"
    My guess would be that was the press release to which P.H. was referring.
    Unfortunately archived press releases prior to 2009 are no longer available on the MO website.
    Actually this seems to be an example of the MO "fence sitting" on the subject, with several, often contradictory statements, which I personally find difficult to interpret.
    It says "ice invariably recovers from extreme events", but also that "About half of the climate models.... show that ice declines in steps - failing to recover from extreme years. If "about half" of the models show that, it presumably means that "about half" of the models don't.
    The final sentence, "if the rate of global temperature rise increases then so will the rate of Arctic sea-ice decline" is fairly obvious and doesn't require a climate model
    , but note it refers to increase in the "rate" of temperature rise".
    As is often the case with the MO press releases, you have to read between the lines.

  • Comment number 95.

    I notice that the DMI above 80N is showing 'normal' temps at the moment following a drop which coincided with the late rise in arctic sea ice. Is there a chicken and egg thing going on here?

    Have the temps come down because the extended sea ice is acting as an insulator, preventing ocean to atmosphere heat transfer over a wider area. Alternatively, have the colder temps allowed more sea ice to form and stay intact as the currents move the ice further south?

    What if anything, does this tell us about the net heat transfer at these higher latitudes. On balance, does a reduction in summer sea ice allow more ocean heat loss than it gains through the reduction in albedo? If so, would that be a negative feedback?

  • Comment number 96.

    Story here: http://www.bbc.co.uk/news/science-environment-17488450

    "Global temperatures could rise by 1.4-3.0C (2.5-5.4F) above levels for late last century by 2050, a computer simulation has suggested."

    Even I call BS on that one. I would say nothing is impossible, but 3C by 2050 is so implausible it might as well be impossible. Warming would have to average about 0.6C per decade to get there. I can only imagine the top end is based on an implausibly high emission scenario plus an implausibly high climate sensitivity.

  • Comment number 97.

    @93 John Marshall

    2007 was the bottom of the cycle and it's increasing? How does 2011 fit in with that idea? Double dip bottom?

  • Comment number 98.

    #96. - quake wrote:
    "Even I call BS on that one. I would say nothing is impossible, but 3C by 2050 is so implausible it might as well be impossible. Warming would have to average about 0.6C per decade to get there. I can only imagine the top end is based on an implausibly high emission scenario plus an implausibly high climate sensitivity."

    I think that a lot more information is required before any conclusions can be drawn.
    Even the first paragraph is misleading, because it refers to "a computer simulation", then goes on to say 10,000 simulations were run.
    We would need to know the distribution of temperature predictions and the assumptions made. Unfortunately with 10,000 simulations that's a lot of data, so it would be of little use to publish it in raw form.
    There are some puzzling aspects to this. For example, what does "the late last century" mean. Also, the article says that "People planning for the impacts of climate change need to consider the possibility of warming of up to 3C by 2050, even on a mid-range emission scenario, the researchers say. "
    So if there is warming of 3c from "mid-range" emission scenarios, that implies a larger rise from higher emissions.
    Unless more information is made available, I would be reluctant to accept any of the predictions.
    There seems to be a lot more information in the Nature Geoscience article and no doubt more information could be obtained by digging around on the climateprediction.net website, so I will reserve judgment until I have had a chance to look at those.
    In any event, trust the BBC to go with only the highest rise in their headline, even though it is probably unlikely.

  • Comment number 99.

    This is becoming a habit.

    Yet another *new* record high March temperature for Scotland (beating yesterday's *old* one): http://www.bbc.co.uk/news/uk-scotland-north-east-orkney-shetland-17512701

    This, and the recent record-smashing March heat in the US and Canada doesn't prove, by any means, that AGW theory is true.

    It *may* just count as evidence supporting the projection, based on AGW models, that record warm temperatures globally should be increasingly common, while record cold ones should be less frequent.

    Therefore the ratio of record high to record low temperatures should be increasing right about now.

  • Comment number 100.

    Late entry for the Guess the temp comp? This is a quote of big Joe Bastardi on WUWT -

    "They had .44 according to the running mean they use ( 1961-1990) and so I had to translate that to my forecast which would be .22 ( I believe that is the difference in the latest 30 years and theirs, which I cant trust since its part satellite and part non satellite. I wish they would just come along into the satellite era, as its more objective). I believe they said it was .34 which would mean it was closer to theirs than mine, if that is the number, and I am not going to argue with them. If I have to go against them, they I have to use their results. They also said 3 of the 6 years would be the hottest on record 2010-2015. Well this year I have it at . 24 against their means, which would mean the push is .29. I needed to adjust for whatever it is they are doing, and since last year was around -.34, I figure this year I have to be smart about it.after all if its colder I win anyway."

 

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