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La Nina returns - what impact on global climate?

Paul Hudson | 12:27 UK time, Friday, 16 September 2011

After a lull over the last few months, weak La Nina conditions are re-establishing themselves in the Pacific.

La Nina is a term used to describe an area of water that is colder than average in the tropical Pacific.

It follows on from the major La Nina event which lasted from June 2010 to May 2011 which was one of the strongest on record, and which depressed global temperatures.

The last back to back La Nina event was recorded from 1998-2000.

In some areas of the world La Nina is a very important forecasting tool, as the colder than average ocean directly impacts pressure patterns, which in turn can lead to extreme weather.

In America, La Nina was blamed for this spring's flooding and drought.

It is also thought that La Nina last year was to blame for Australia's second wettest year since 1900, and forecasters believe another cool and wet summer in that part of the world is on the cards, although flooding on the scale that was witnessed last summer is thought unlikely.

Closer to home, there is little evidence to indicate how, if at all, La Nina impacts weather here in the UK.

As for global temperatures La Nina will have a cooling influence, depending on its strength and longevity.

Climate experts at NOAA believe that La Nina conditions will slowly strengthen and continue through winter.

And the Japanese climate centre expects weak La Nina conditions to continue into next year, and then strengthen by Spring 2012, as can be seen from the two projections below.

Comments

  • Comment number 1.

    "As for global temperatures La Nina will have a cooling influence, depending on its strength and longevity."

    That would make 15 years of no global warming since the peak in 1998 then.

  • Comment number 2.

    All without any influence from solar cycle 25, hmmmm.

  • Comment number 3.

    Snowshoes out of the cupboard ready for winter again. With energy prices as they are this will be a tough one for a lot of people, and if the weather patterns are similar the good old wind farms will stand silent and frozen and the solar farms covered in a foot of snow.

    £10 billion well spent there, eh?

  • Comment number 4.

    Australian flooding was due in no small part to the failure to empty the dams soon enough, as warmist doctrine forbade opening the dams even when they were way over the safe level. The flooding of Brisbane was a man-made disaster if ever there was one. Are you certain that there is no connection between La Nina and the 2 successive cold winters in the UK and USA?

  • Comment number 5.

    "Are you certain that there is no connection between La Nina and the 2 successive cold winters in the UK and USA?"

    The cold winters were due to the sun going into a quiet phase. It had been previously enjoying its noisiest 50 year period for a millennium. This coincided with the gentle warming we also enjoyed on earth. Of course, the bedwetters say the two are unconnected. Well they would..

  • Comment number 6.

    The last two cold winters in the UK and USA, Northern Europe and Northern Russia were in contrast to very warm winters in Greenland/Canada. Overall the average temperature of the last two northern hemisphere winters was quite normal in terms of winters of last decade. The difference was that there was a sharper contrast in temperature between the two regions.

    There is a hypothesis that the solar minimum shifts the jet stream further north or south, or something like that which causes such a sharp contrast.

  • Comment number 7.

    There appears to be no effect yet on global temperatures, which at the moment seem to be generally rising.
    However, the August UAH tropics anomaly did show a fall from 0.22c to 0.15c, although that was mainly due to a fall in the land component, from 0.36c to 0.20c.
    Also, the RSS -20 to +20 degree combined anomaly fell from 0.234c to 0.210c. I am not sure if RSS publish separate figures for land & ocean.
    The biggest fall in the RSS anomalies was for -20 to -70 degrees, from 0.211c to 0.068c, which would not appear to be related to La Nina.
    I notice that in the second of the above predictions, the lowest sst anomalies appear to be in the North Atlantic. Presumably that is not caused by La Nina.

  • Comment number 8.

    If in December if we take a map of SON 2012 temperature observations and compare them to the posted forecast map of SON 2012 temperatures I wonder how many pixels will be match?

    I would be cool if the resolution of such maps was changed over time to aim for something like 95%+ pixels to be correct.

    Ie on the current SON forecast map it looks like each pixel represents less than 1x1 degree area on the globe. If it turns out in December that 70% of the those pixels on the September-October-November forecast map were wrong, then the next SON forecast map should use say 2x2 degree pixels. Keep changing the resolution like that until 95% accuracy is achieved. Lets say eventually it settles on 10x10 degree pixels. A very blocky forecast map but at least you could look at it knowing that 95% of the pixels were likely to be correct.

    And if over time the forecast skill increased you would be able to see the resolution increasing on the maps.

  • Comment number 9.

    PingoSan wrote:
    "That would make 15 years of no global warming since the peak in 1998 then."

    Which 15 years would that be?

  • Comment number 10.

    PingoSan wrote:

    " It had been previously enjoying its noisiest 50 year period for a millennium."

    Which 50 years and was it this millennium?;
    http://www.grandunification.com/hypertext/Heliometeorology.html

  • Comment number 11.

    Lazarus - what a truly bizarre link - what on Earth are you trying to say?

  • Comment number 12.

    "what on Earth are you trying to say?"

    The link shows sun spots since the 1700s. Sun spots and related to the suns activity which PingoSan claims went into a quite phase compared to the nosiest 50 years in a millennium. I cannot verify such a claim from any evidence I can find - does anyone even have 1000 years of recorded solar activity? Nor can I see any striking difference of any 50 year period from the records I have found.

    Sorry for being a sceptic and expecting evidence.

    Back to back La Ninas are bad news. The droughts in weird weather weather in the US are thought to have been exasperated because of last years La Nina. This could indicate the Texas drought is set to continue for some time.

  • Comment number 13.

    Paul,
    If we look at this Japanese forecast for the cold La Nina returning in conjunction with the fast and early re-build of the Arctic Ice this year (it's already snowing in Colorado) and the continuing quiet sun - we have the build up to another very cold winter ?

    http://notrickszone.com/2011/09/16/2011-record-arctic-ice-melt-not-even-close/

  • Comment number 14.

    lazarus

    Well of course 1000 yrs of ssn is going to involve some proxy reconstruction. Numbers since around 1600 are considered more reliable and these do back up what Pingosan is saying. The increase in activity is quite unmistakable and as far as I know, not challenged by either side of the AGW debate.

    Looking further back, Usoskin et al 2003 have a 1000 year reconstruction which also backs up the unusually high solar activity of the late 20thC. You'll like this one, since they conclude that although the late 20C solar activity is unusually high, that in itself, cannot be responsible for the temp increase post 1970. Others would disagree with their conclusion I'm sure.

  • Comment number 15.

    On topic . .
    should we expect the double dip to cause an increase in OHC by the middle of next year?

  • Comment number 16.

    On September 15th., the AQUA CH5 temperature showed the largest daily fall so far this year, of -0.085c, which is about 5 times the average rate of fall at this time of the year. Of course, from past experience this rate of fall will not be sustained and there will shortly be another period of temperature rise, but it may be a sign that the average rate of fall is starting to approach normality.
    However, we are half way through September and it seems unlikely that even if the rate of fall does increase, that it will make a great deal of difference to the overall September anomaly.
    On the other hand, after getting very close to 2010 daily temperatures around September 13th., the risk of this year's temperatures exceeding those of 2010 seems to have been averted, at least until the end of September.

  • Comment number 17.

    Apparently 11 wind farms in the UK were closed down last week, during the strong winds, and paid £2.6 million NOT to generate electricity.
    Of course, the cost of this will have to be paid for by UK consumers.
    http://www.telegraph.co.uk/earth/energy/windpower/8770937/Wind-farm-paid-1.2-million-to-produce-no-electricity.html
    So we have reached the point where wind farms are paid more not to generate
    electricity than they would be to generate it.
    Is it just me, or is this world becoming more and more like Alice In Wonderland?

  • Comment number 18.

    "The link shows sun spots since the 1700s. Sun spots and related to the suns activity which PingoSan claims went into a quite phase compared to the nosiest 50 years in a millennium. I cannot verify such a claim from any evidence I can find - does anyone even have 1000 years of recorded solar activity? Nor can I see any striking difference of any 50 year period from the records I have found."

    here you go.

    Rigozo, N. R.; Echer, E.; Vieira, L. E. A.; Nordemann, D. J. R. (2001). Solar Physics 203: 179–191

  • Comment number 19.

    For all those who believe in Global warming, King Canute is laughing at you. If I was you I would get down to B&Q and buy some insulation for your loft, at £3 a roll. 5 rolls did 400mm depth in both the eves of my house. I learnt from working in a bank, that statistics can be made to say what ever, you want them to. I left the bank because I knew there would be a banking crisis, with what was happening behind the scenes. It isn't over by a long way. People have to use their common sense and the UK is a good barometer of what is happening weather wise in the rest of the world, much like in the financial world. It is time to smell the coffee.

  • Comment number 20.

    QV, Sheffield_city

    Through the looking glass!:
    http://www.bishop-hill.net/discussion/post/1598019

  • Comment number 21.

    PingoSan wrote:

    "here you go.

    Rigozo, N. R.; Echer, E.; Vieira, L. E. A.; Nordemann, D. J. R. (2001). Solar Physics 203: 179–191"

    The problem with your link is that it doesn't support what you claim. There is no correlation between the modern maximum and the 'gentle warming we also enjoyed on earth';
    http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/solact.html

  • Comment number 22.

    "There is no correlation between the modern maximum and the 'gentle warming we also enjoyed on earth';"

    So which of the two didn't occur?

  • Comment number 23.

    The AQUA CH5 temperature fell another 0.087 degrees on September 16th., making a fall of about 0.17 degrees in two days. This is by far the fastest two day rate of fall this year and much faster than the average at this time of the year. The effect of this on the cumulative figure for September is still not significant, and even if this rate of fall were to continue until the end of the month, while the daily temperatures would be impossibly low, the cumulative anomaly for 2011 would remain higher than it was at the end of September and the equivalent UAH anomaly would only be slightly lower than at the end of August.
    This daily fall would be the 9th in succession and recently periods of falling temperatures have tended to last about 10 days, interspersed with shorter periods of rising temperatures.
    Clearly, the length of time the current period of falling temperatures continues will be critical in determining the eventual cumulative anomaly for September.

  • Comment number 24.

    La Nina is a vital part of the ocean cycles in the Pacific because it brings nutrients from the depths as well as dissolving more CO2 in surface waters both of which mean more food available for wildlife and those humans living in the area.

    The PDO, of which the La Nina is part, certainly affects global climate due to the heat transfers going on. Global means the UK is included Paul.

  • Comment number 25.

    5. PingoSan wrote:

    "The cold winters were due to the sun going into a quiet phase. It had been previously enjoying its noisiest 50 year period for a millennium."

    If the cold winters in the UK and USA in 2009/2010 were the result of reduced solar activity why was this not reflected in global temperatures during those periods? Surely a solar explanation would have a global impact?

    Dec-Feb 2009-10 was the second warmest 'winter' globally in the UAH record. Dec-Feb 2010-11 was slightly cooler, but still 13th warmest globally in UAH; well above average.

    NH temperature data doesn't support your assertion either. According to UAH the NH was much colder on average during Dec-Feb 2007/2008 than it was during either Dec-Feb 2009/10 or 2010/11.

    In fact TSI records indicate that solar output Dec-Feb 2008/09 was actually *lower* than it was during both 2009/10 and 2010/11: http://www.woodfortrees.org/data/pmod/plot/none

    Doesn't look like solar is a very good explanation for global or NH Dec-Feb temperatures over the past few years.

  • Comment number 26.

    Climate does not change overnight. It'll take a couple of decades for the sun to have an effect across the whole globe. In the UK we are most prone to it, due to blocking highs over Greenland being more common at times of solar quietness.

  • Comment number 27.

    Doesn't that mean greenland gets warmer at times of solar quietness?

  • Comment number 28.

    26. PingoSan wrote:

    "It'll take a couple of decades for the sun to have an effect across the whole globe".

    Sorry, are you saying that the cold winters of 2009/10 and 2010/11 are the result of changes in solar activity from 'a couple of decades' ago?

    There was a steep dip in both sunspot numbers and TSI in 1997. Is this the period that you believe has been responsible for the cold UK winters of 2009/10 and 2010/11?

    If so, then should we expect to see a rise in UK winter temperatures over the next few years, corresponding to the sharp rise in solar activity observed from 1998-2003?

    http://www.woodfortrees.org/plot/sidc-ssn/every:12/from:1979/normalise/plot/pmod/every:12/normalise:1979

  • Comment number 29.

    Long range forecast from 1979, using a study of bristlecones,covering the period upto 2150

    http://news.google.com/newspapers?id=aJpjAAAAIBAJ&sjid=N3wDAAAAIBAJ&pg=6824,139587&dq=global+warming&hl=en

  • Comment number 30.

    The latest AQUA CH5 temperature, for September 17th., shows another fall, this time 0.103 degrees in a single day, thats 0.275 degrees in 3 days.
    Because the temperature normally falls at this time of year, the actual AQUA CH5 anomaly has "only" fallen by 0.225 degrees over 3 days.
    I don't know if it's La Nina, but something is cooling the atmosphere very quickly at the moment.
    Will this situation continue long enough to have a significant effect on the overall September anomaly?
    This also seems to to be reflected in the current GFS map, which seems to be showing and forecasting fewer areas of high positive anomalies and more negative anomalies than usual, particularly in the South Polar region, but the situation seems to be forecasted to change in about 5 days.
    http://coaps.fsu.edu/%7Emaue/extreme/gfs/current/raw_temp.html

  • Comment number 31.

    "Sorry, are you saying that the cold winters of 2009/10 and 2010/11 are the result of changes in solar activity from 'a couple of decades' ago? "

    No, they are as a result of the UK being most prone to cold winters at the moment, due to blocking highs over Greenland being more common at times of solar quietness.

    I refer you again to post 26. Do you find reading difficult?

  • Comment number 32.

    "Doesn't that mean greenland gets warmer at times of solar quietness?"

    Why would a blocking high over Greenland make Greenland warmer?

  • Comment number 33.

    31. PingoSan:

    [In response to "...are you saying that the cold winters of 2009/10 and 2010/11 are the result of changes in solar activity from 'a couple of decades' ago?"

    PingoSan writes:

    "No, they are as a result of the UK being most prone to cold winters at the moment, due to blocking highs over Greenland being more common at times of solar quietness."]
    __________________________________________

    Dec-Feb 2008/09 was a period of lower solar activity than both Dec-Feb 2009/10 and 2010/11, yet according to the CET record, average surface temperatures were higher in central England in Dec-Feb 2008/09 than they were in both Dec-Feb 2009/10 and 2010/11.

    I guess that blocking mechanism over Greenland only works in certain years?

  • Comment number 34.

    "I guess that blocking mechanism over Greenland only works in certain years?"

    Don't be so disingenuous. If there was a perfect match between the sun and the UK climate, we wouldn't need weather forecasters. There is a decent and significant signal from the quiet sun, but it isn't the only factor, and nowhere did I suggest it was.

  • Comment number 35.

    All three winters were below normal which backs up my argument.

  • Comment number 36.

    Actually, there are a few (warmist) bods who agree with PingoSan on this - see link. It's primarily a weather issue so I'm surprised by the defensive nature of some of the responses.
    http://tiny.cc/pbsia

  • Comment number 37.

    35. PingoSan:

    Your argument is that low TSI correlates to low winter temperatures in the UK.

    During Dec-Feb 2006/07 TSI was at its second lowest output since satellite records began in 1979.

    Yet during Dec-Feb 2006/07 average CET temperatures were +6.4 C - the fourth warmest Dec-Feb in the 352 year CET record.

    How does your argument explain this?

  • Comment number 38.

    "Your argument is that low TSI correlates to low winter temperatures in the UK."

    No it isn't. Poor strawman.

    There is more complexity to the sun's output than Total Solar Irradiance.

  • Comment number 39.

    38.PingoSan:

    You're being a bit vague here. TSI, like sunspots, is an indicator of solar activity. What are you using as an indicator of solar activity?

  • Comment number 40.

    message for our host . . .
    perhaps a post on clouds is becoming unavoidable? Sit back and enjoy the fireworks.

  • Comment number 41.

    "You're being a bit vague here. TSI, like sunspots, is an indicator of solar activity. What are you using as an indicator of solar activity?"

    UV Levels, which affect pressure patterns around Greenland, were very low during last few years. When you get low UV, you tend to get high pressure over Greenland.

    http://wattsupwiththat.com/2011/09/20/uv-low-during-recent-solar-minimum/

    There are several facets to the sun's output than simple TSI, all of which are likely to have impact on earth.

    I understand you wanting to use TSI though, as it's usually the one that shows least variation - so you point to TSI and say, "hey, it can't be the sun, can it?".

    Shall I bookmark this to quote it back to you in a few weeks?

  • Comment number 42.

    41. PingoSan:

    You're suggesting that when you were referring to a "quiet sun" you were actually referring to reduced UV levels, as opposed to reduced TSI or sunspot activity (even though you linked @ 18 to a paper on sunspot activity to support your claims @ 5).

    OK: can you cite your source for your claim that "UV Levels, which affect pressure patterns around Greenland, were very low during last few years" please?

    We'd need to know how long UV levels have been low before we could attribute this as a possible cause of the cold winters of 2009/10 and 2010/11. For instance, if UV levels were low before 2009 then we'd probably want to know why the cold winters didn't kick in earlier.

  • Comment number 43.

    Paul Hudson has commented in the past about the link between low solar activity and colder winters in Europe and the paper by Lockwood (in lateintheday's link @ #36) certainly appears to confirm this. However, I get the impression that the mechanism for it is not yet fully understood.

    Having checked back over some of the pressure charts, it appears that the "blocking" high pressure areas during our recent cold spells have for the most part been further east than Greenland - more typically over Scandinavia or closer to Iceland. However, I think it's fair to say that parts of Greenland have been warmer than normal.

    I also seem to remember a paper from a year or so back which proposed a link between reduced sea ice in the Arctic and a greater incidence of negative Arctic oscillations - these also lead to colder conditions in Europe:

    http://nsidc.org/arcticmet/patterns/arctic_oscillation.html

    Certainly, the arctic oscillation has been negative during the cold spells of the last couple of winters:

    http://earthobservatory.nasa.gov/IOTD/view.php?id=47880

    This obviously doesn't prove anything, but it's something else to bear in mind.

    Paul

  • Comment number 44.

    I have been away for a while. Has there been any discussion on the falsification of the Greenland ice-cap by the Times Atlas?

  • Comment number 45.

    Hudsonfan
    no discussion as yet. Falsification seems a tad over the top unless you've got info to back it up. More likely, just a mistake.

  • Comment number 46.

    I see GISS (up a bit) and NCDC (down a bit) are now out.
    Does anyone know why HadCRUT3 seems to take so long to come out these days?

  • Comment number 47.

    NeilHamp,
    Regarding HadCRUT3, the last time I checked with the UKMO (June?), the reason for late publication was late arrival of data from some locations and a "minor problem with the data base".
    Assuming that the "minor problem" has now been sorted out, the answer is presumably still late data. I think the UKMO must still be using the "runner with a cleft stick" approach to data transfer. Also, given that the UKMO routinely publishes other data (UK rainfall) before the end of the period in question, then revises it, I don't know why they are so strict on monthly HadCRUT3.
    From past experience the HadCRUT3 figure should be out very soon. However, my estimate, based on the HadSST2 figures, which are already published, is that the August global HadCRUT3 figure will be about 0.42c.

  • Comment number 48.

    The AQUA CH5 temperature appears to have started to rise again after falling for 12 days. If recent experience is anything to go on, the temperature will rise for a few days and then start to fall again. During the rapid fall period, the temperature got to within about 0.1 degrees of average and depending on how much the temperature increases during the warming phase, it may again challenge the average before the end of September. There seems little likelyhood of it exceeding the daily 2010 figure before the end of the month.
    My best estimation for the overall September UAH figure, based on AQUA, is about 0.4c, compared to the August figure of 0.325c, but the margins of error are very large.

  • Comment number 49.

    I wonder if it's coincidence that the HadCRUT delay has occurred ever since they were forced to release station data they obtain from their sources publicly (which has turned out to have no benefit afterall)

    A similar thing happened with GISTEMP. The monthly GISTEMP figure used to release with a few days of each month. Since skeptics forced a pointless QA procedure change at GISS the monthly anomaly now takes significantly longer to be released.

    Releasing preliminary data for these datasets turns out not to be worth the PR hit when skeptic blogs are sitting ready to spin any error in preliminary data into news articles telling everyone that a serious error at NASA GISS has affected all the science ever.

 

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