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Summer 2012 - 2nd wettest on record

Paul Hudson | 15:15 UK time, Thursday, 30 August 2012

UPDATE at 6pm Friday 31st August

Last night was the coldest August night on record at Leeming (1.1C, records to 1945) and Bradford Lister Park (2.8C, records to 1908).

Summer at Leeming was the fourth wettest, and the dullest on record.

At Sheffield Weston Park it was also the fourth wettest summer in records which date back to 1882, with 2007, 1912 and 1956 all wetter than this summer.

ENDS


The Met Office have said that summer 2012 will be the second wettest (summer is June, July and August combined for statistical purposes) on record across England and the UK as a whole, using rainfall data back to 1910.

So far 367mm of rain has fallen, compared with 384mm which was recorded in 1912.

It's also been the dullest summer since 1980, and cool, with mean temperatures 0.4C below average,

It adds to a depressing sequence of summers across the country, with the last 6 years all being wetter than average.

Moreover 2 of the 3 wettest summers on record have happened in that time - 2007 and 2012.

The reason for our poor summers is the jet stream.

It's been consistently too far south over the last few years, and is the reason why we've experienced some cold winters recently, too.

The big question is why is the jet stream behaving in this way?

There are two current theories, which I detailed in my earlier blog which you can read here.

One is linked to melting Arctic ice, which fell to a satellite record low on Monday.

The other theory suggests it's down to the protracted low solar activity over the last few years, as happened in the early 1800's.

And if the early 1800's are anything to go by, poor summers and cold winters may be something we need to get used to in the next few years.

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Comments

  • Comment number 1.

    Perhaps the law of averages will allow us a good summer next year. Did any long range forecaster predict this awful summer?

  • Comment number 2.

    So not as wet as 1912, based on the "short" UK series, which only goes back to 1910. It's just as well that they didn't start in 1913, or we would be being told that it was the wettest summer "ever".
    Based on the longer HadUKP series, it's possible that in England & Wales, 2012 was not as wet as 1912, 1879 and 1829, but we will have to wait for the official August figures to be certain.
    Recent rainfall has been high relative to the 60's and 70's, but the summer rainfall trend is falling and the 30 year average is currently much lower than in the 1850's.
    So proponents of "climate change" will have to decide if it is causing higher or lower rainfall in summer. Or is it whatever it happens to be at the time?

  • Comment number 3.

    #1. - Gadgetfiend wrote:
    "Did any long range forecaster predict this awful summer?"
    Not sure, but the MO predicted drier than average April-June, (and as far as I remember, May-July), but that was when we were having a drought.
    Personally, I don't think the summer was that bad, but then I don't like it too hot and I like rain.

  • Comment number 4.

    Hmm. I wonder if the low solar activity could also be a reason for the low ice in the Arctic? I've seen reports that ice levels were low in the early 1800's and 1900's. Odd that these similarities seem to be approximately a century apart. A solar cycle anyone?

  • Comment number 5.

    Wasn't the time around the first world war extremely cold. Watch out as nature balances things back out. It is time that people understood cause and effect. The world is much like a heating system with a thermostat, God isn't stupid.

  • Comment number 6.

    I noticed that we had some extremely cold nights across the country last night. -2 in Scotland and 3 degrees in Bradford.

  • Comment number 7.

    4. buythermals wrote:

    "Hmm. I wonder if the low solar activity could also be a reason for the low ice in the Arctic?"

    Why would low solar activity, i.e. reduced TSI, *decrease* ice cover in the Arctic? Surely if there is less heat energy from the Sun you'd expect to see the opposite.

  • Comment number 8.

    #6. - Tim wrote:
    "I noticed that we had some extremely cold nights across the country last night. -2 in Scotland and 3 degrees in Bradford."
    Of course, since the cold air was coming from the North, that probably means that it is warmer than average where the air came from.

  • Comment number 9.

    It's not necessarily just about TSI is it. Lots of 'pet theories' out there if you're willing to delve a little deeper. Of course, since they are not mainstream, you may consider them unworthy of your attention. But just remember that AGW was not mainstream until it became mainstream.

  • Comment number 10.

    'Why would low solar activity, i.e. reduced TSI, *decrease* ice cover in the Arctic? Surely if there is less heat energy from the Sun you'd expect to see the opposite.'

    Who mentioned heat energy? The sun puts out a wide range of electro-magnetic energy. This interacts with the atmosphere, the earth's magnetic field and cosmic rays in a myriad of ways which are only partially understood.

  • Comment number 11.

    Just wanted to make a comment regarding Paul and Christa's mention of being 'told off' for mentioning 'brass monkeys' regarding temperature. Since the old expression "It's cold enough to freeze the balls of a brass monkey" is based in something entirely innocent, I fail to see why they would be told off. It relates to the triangular brass mounting that cannon balls were placed on next to cannons, which would often freeze and cause the cannonballs to fall from their mount during inclement winter weather. Sorry for being pedantic - just thought I'd mention it, as people bastardising perfectly innocent comments for rudeness annoys me. And no, bastardising is NOT a rude word haha.

  • Comment number 12.

    #11. - matthewLEEDS wrote:
    "It relates to the triangular brass mounting that cannon balls were placed on next to cannons, which would often freeze and cause the cannonballs to fall from their mount during inclement winter weather."

    I'm afraid it isn't as clear-cut as that.
    According to Wikipedia, it might be an urban legend and personally I think that explanation might have been made up to "clean up" the expression.

    http://en.wikipedia.org/wiki/Brass_monkey_%28colloquial_expression%29

    Next time you visit an old sailing warship, ask to see the "brass monkeys".

  • Comment number 13.

  • Comment number 14.

    "One is linked to melting Arctic ice, which fell to a satellite record low on Monday.

    The other theory suggests it's down to the protracted low solar activity over the last few years, as happened in the early 1800's."


    Well the Arctic ice has been reducing for 30 years or so, if not since the LIA,
    so one would have thought that the more meridional jets would have developed at least 30 years ago. They didn't.

    By my observations the jets stopped becoming more zonal around 2000 which correlates with the decline of solar activity from the peak of cycle 23.

    The minimum of cycle 24 was the lowest for over a century and coincided with a record negative Arctic Oscillation and jets very meridional / equatorward.

    So if I were a betting man the appropriate choice would be obvious.

  • Comment number 15.

    Yes, another exceptionally cool wet summer - finishing with an unusually cold night.

    Let's not forget, of course, that the cold wet weather began long before the summer started - in April. For almost unrelenting miserable weather for such a long period - the record may have been exceeded? And it remains to be seen if it will yet end before wheat crops are almost entirely ruined.

    Dullest summer since 1980 perhaps - but May 1980 had one of the most remarkable sunny periods ever, if I remember correctly? - 9 consecutive days of cloudless weather over the entire British Isles.

    As for the early 19th cent - this was complicated by a period of exceptional volcanic activity (as we have said before) so comparisons are difficult.

  • Comment number 16.

    14. Stephen Wilde wrote:

    "The minimum of cycle 24 was the lowest for over a century and coincided with a record negative Arctic Oscillation and jets very meridional / equatorward."

    What do you mean by "the minimum of cycle 24" Stephen?

    When was this minimum?

  • Comment number 17.

    With respect to the sun cycles, isn't the minimum the same across lots of cycles but the maximum varies (higher, lower)? i.e the minimum is zero sunpots?

  • Comment number 18.

    matthewLEEDS. Most things are innocent until the pc brigade get stuck into them. I would say the people who complain are the ones with a dirty mind, because they see hidden reasons that most ignore. There will be nothing left of the Britain I loved as a child, if certain people had their way. Global warming is another one of those things, where people look for something that isn't really there.

  • Comment number 19.

    #14. - Stephen Wilde wrote:

    "The minimum of cycle 24 was the lowest for over a century and coincided with a record negative Arctic Oscillation and jets very meridional / equatorward."

    You probably mean the minimum between cycle 23 and 24, or at the start of cycle 24.
    In terms of sunspot numbers, I estimate that this happened in June 2009, with a 12 month average ssn of 1.68, although you could say Dec. 2008, if you calculate the average in the centre of the 12 month period.
    It is true that was the lowest minimum 12 month ma since 1913, but personally, since by definition, all minimums have low ssn, I don't think that was as significant as the fact that, again measured by average minimum ssn, cycle 23 was the longest since cycle 9, which ended in 1856.

  • Comment number 20.

    #17. - john_cogger wrote:
    "With respect to the sun cycles, isn't the minimum the same across lots of cycles but the maximum varies (higher, lower)? i.e the minimum is zero sunpots?"

    It's difficult to define the max & min of sunspot cycles using sunspot numbers.
    Personally I use the 12 month mean and then it depends on where you centre the average.
    While individual monthly ssn figures can be zero, the 12 month average is rarely zero, although it was in cycle 5, which ended in 1811. In fact, there have only been 68 months out of 2163 (2.15%) with zero ssn since 1749, and the last one was in August 2009, so you could argue that was the end of cycle 23, but a problem arises when there are two months with zero figures (68 monthly zero figures in 24 cycles), which is why I use the 12 month average.
    I calculated that the 12 month average ssn was 1.68 at the end of cycle 23, compared to a figure of 8.14 at the end of cycle 22, 12.33 at the end of cycle 21 and 11.93 at the end of cycle 20.
    So there is quite a lot of variation in the 12 month minimum figures, athought it's not as obvious as the maximum.

  • Comment number 21.

    #18. - Tim wrote:
    "matthewLEEDS. Most things are innocent until the pc brigade get stuck into them. I would say the people who complain are the ones with a dirty mind, because they see hidden reasons that most ignore. There will be nothing left of the Britain I loved as a child, if certain people had their way. Global warming is another one of those things, where people look for something that isn't really there."
    Another example is the "V" sign, and the myth that this was started by British archers, to show that they could still fire their arrows, which apparently isn't true (according to QI that is!).
    The meaning of this seems to depend on whether the hand is presented forwards or backwards, and also, of course on whether there in any upward movement of the hand.
    I suspect the "rude" version of this only started in the 50's, since Churchill happily used both the forward and backward versions during the war, to symbolize victory, although he may have been sending an insulting message to the Germans.

  • Comment number 22.

    Further to my previous comment here's some interesting stuff about the lack of ice in the early 20th and 19th centuries:
    http://wattsupwiththat.com/2008/03/16/you-ask-i-provide-november-2nd-1922-arctic-ocean-getting-warm-seals-vanish-and-icebergs-melt/
    and
    http://wattsupwiththat.com/2009/07/28/statement-on-arctic-climate-change-from-the-president-of-the-royal-society/

    So that's 1817, 1922 and 2012. Correlation doesn't mean there's any sort of link but quite a coincidence. And very little man-made CO2 around then. We live in interesting times.

  • Comment number 23.

    QuaesoVeritas. I understand the V sign came from Agincourt. The English archers used to put up their two fingers to show they still had them, if the French got hold of a English archer they used to cut off their fingers. There are a number of different versions of Scarborough warning.

  • Comment number 24.

    An interesting idea:

    'The imbalance between land and ocean area in the north compared to the south means absorbed energy has to cross from south to north because the ocean absorbs and retains more solar energy than the land surfaces. Because cloud amount reduced since at least 1960 all the way to the super el nino of ’98, as shown by the new papers from Spain and China and worldwide, more solar energy entered the oceans, predominantly in the southern hemisphere. Yet the southern hemisphere didn’t warm as much as the northern. So energy must have been transferred in ocean currents from south to north. The increase in solar energy will have increased the velocity of these currents. This could be why the Gulf Stream moved northwards, hitting Greenland and helping to warm the arctic ocean. That could be part of the reason why arctic ice has reduced while antarctic sea ice has increased.'
    http://tallbloke.wordpress.com/2012/09/01/earths-energy-balance-some-observations-in-the-light-of-new-evidence/

  • Comment number 25.

    22: Any idea of what happened to the recent Met Office graph showing Arctic ice increasing since 2007? I've heard it might have gone 'reprocessing'. Anyone got any idea?

  • Comment number 26.

  • Comment number 27.

    Re 22:

    There are estimated maps of sea ice going back to 1893 here:
    http://brunnur.vedur.is/pub/trausti/Iskort/Pdf/

    The map for August 1922 suggests the sea ice back then was far more extensive than it has been this August:
    http://brunnur.vedur.is/pub/trausti/Iskort/Pdf/1922/1922.pdf

  • Comment number 28.

  • Comment number 29.

    #25. - Boanta wrote:
    "Any idea of what happened to the recent Met Office graph showing Arctic ice increasing since 2007? I've heard it might have gone 'reprocessing'. Anyone got any idea?"
    Are you referring to this one?
    http://notalotofpeopleknowthat.wordpress.com/2012/09/04/the-mystery-of-the-disappearing-graph/
    There is a MO explanation on this page, whether or not you wish to believe that.

  • Comment number 30.

    Solar activity is down, microwave and magnetic, which cools the planet. Arctic ice cover may have been misreported for several reasons including the problem satellites have reporting melt ponds on the ice. These frequently form, and refreeze, but the satellites report these as clear water.
    newDWR54 did not like my claims for Dr Tim Ball as being a climatologist. he should read all Dr Ball's CV. He worked in the Arctic 64-68 on Search and Rescue, actually flying, and his many papers are concerned with climate. He can be called a Climatologist. But many people believe James Hansen, an astrophysicist whose many papers are mostly alarmist climate papers not peer reviewed. The chairman of the IPCC is called a climatologist when in fact he is a railway engineer with a PhD in Economics. Hardly an expert in the relevant subject. Who would you believe?

  • Comment number 31.

    29 QV---thanks, most helpful and most amusing too.

  • Comment number 32.

    The official rainfall figures for August are now available in the data files.
    The U.K. August rainfall figure, based on the "short" regional series, was 109.5mm, bringing the summer total to 370.7mm, compared to 384.4mm in 1912, meaning it is still only the 2nd wettest summer in the series.
    The England & Wales figure for August, based on the HadUKP series, which goes back to 1766, was 93.7mm, bringing the summer total to 374.3mm, making is lower than 1912, 1879 and 1829, and only 3.5mm higher than 1860.
    The summer total brings the HadUKP 30 year summer moving average to 216.54mm, the highest since 1982, but much lower than the highest 30 year MA of 254.7mm, attained in 1857.
    This must present something of a problem to "climate change" believers, since while in the long-term, summer rainfall is lower, in line with theory, in the short-term, rainfall is higher.
    Of course, the explanation will be that while "climate change" theory predicts dryer conditions in summer, the fact that we have recently had more rain, is due to "climate chaos". In fact, this is simply a reflection of normal climate variation.

  • Comment number 33.

    Re 30: "Arctic ice cover may have been misreported for several reasons including the problem satellites have reporting melt ponds on the ice. These frequently form, and refreeze, but the satellites report these as clear water."

    That's a problem around the beginning of August and it can cause rapid days of decline followed by slowdown or even an uptick. But this doesn't explain any of the total decline seen to date. By now air temperatures over the remaining ice are below freezing and any continuing melt is from the bottom of the ice.

    Which ever way you look at it 2012 is significantly lower than 2007, which in itself smashed the previous record in 2005. The only credible explanation is that Arctic sea ice has been getting thinner and it's becoming more susceptible to destruction. Another Arctic storm is forecast in a few day that may bash up a bit more ice.

  • Comment number 34.

    Greensand, for your interest.
    I wonder if the MET model cools its ENSO prediction from September!
    http://www.metoffice.gov.uk/research/climate/seasonal-to-decadal/gpc-outlooks/el-nino-la-nina

    POAMA Forecasts

    Predictive Ocean Atmosphere Model for Australia (POAMA).
    The POAMA model, run at the Bureau of Meteorology, generates a new forecast on day 1 of each month for the following eight months. The most recent model run (September) predicts NINO3.4 has peaked and is likely to fall below the El Niño threshold during spring and remain neutral for the remainder of the forecast period.
    http://www.bom.gov.au/climate/poama2.4/poama.shtml

    This, if accurate, takes us through to summer 2013 and unfortunately I don't foresee where the MET is going to get the additional warming from in time to retain credibility in the decadal forecast:
    http://www.metoffice.gov.uk/research/climate/seasonal-to-decadal/long-range/decadal-fc

  • Comment number 35.

    Did anyone see Newsnight last night?
    There was an item on the decline in Arctic ice, based on a theory by Professor Peter Wadhams, that the decline in the ice was going to "double mankind's contribution to climate change", due to the reduced albedo. However, in my view, the item was biased and contained a number of flaws, exaggerations and false assumptions.
    Peter Lilley, who was on the programme because of his new study of the Stern Review, ironically found himself defending the findings of the latest IPCC report, against the alarmist, short-term views of the Newsnight item and the leader of the Green Party, who was also on the programme.
    It's amazing that although the proponents of "climate change" are forever telling sceptics not to take short-term trends as contrary evidence, they are happy to do so when it comes to evidence in favour.
    Nobody mentioned the fact that whatever we do in the U.K. to reduce emissions, it won't make the slightest difference as long as China is pursuing a massive growth in it's economy and consumption of fossil fuels.
    You can still see the programme on the BBC iPlayer, near the end of the programme.
    http://www.bbc.co.uk/iplayer/episode/b01mmx7q/Newsnight_05_09_2012/

  • Comment number 36.

    35. QuaesoVeritas:

    Wadhams appears to be in a very small minority among those who study Arctic sea ice extent in believing it will be almost gone by 2015. I believe it is his opinion, and not the conclusion of any peer reviewed paper on the subject.

    Having said that, the IPCC AR4 Arctic sea ice projection models have proved to be hopelessly wrong. They have greatly underestimated the observed Arctic ice extent reduction. (A glaring IPCC error that the GWPF or others seldom refer to, for some odd reason.)

    As ever, I'd say the truth lies somewhere in between. The summer ice now looks certain to be as good as gone by mid century at the latest. The only thing that would reverse this is a sudden and sustained reduction in global surface temperature rise and ocean heat content.

    No sign of that as yet.

  • Comment number 37.

    Another point worth noting about the Arctic sea ice extent reduction is the current *rate* of decline.

    According to NSIDC, the observed rate in minimum extent reduction (September average 1979-2011) is currently -840,000 km2 per decade. The thirty year rate is -920,000 km2 per decade. However the ten year rate is -1.7 million km2 per decade; just over double the 1979-2011 average rate of decline. All of those rates of reduction look set to increase further when 2012 values are added.

    Perhaps those fond of citing the 'recovery from the Little Ice Age' as an explanation for the Arctic sea ice decline (and just about every other warming indicator) can offer an explanation for this observed increase in the rate of reduction?

  • Comment number 38.

    #36. - newdwr54 wrote:
    "Wadhams appears to be in a very small minority among those who study Arctic sea ice extent in believing it will be almost gone by 2015. I believe it is his opinion, and not the conclusion of any peer reviewed paper on the subject. "
    And yet the BBC put it forward as new evidence, which was, of course, totally accepted, without question by the new leader of the Green Party, although I suppose that *is* her job to exaggerate the situation. Speaking as a potential "green" myself, I think this "crying wolf" is likely to discredit the party.
    I laughed when Jeremy Paxman said that the BBC were too disorganised to "concoct something like that".
    The IPCC AR4 report is probably out of date, since global temperatures have been more or less static since it was published.
    What I would like to know is how a reduction in the albedo over less than 1%, at a location which barely receives any sunlight for a large part of they year, is going to "double mankind's contribution to climate change".

  • Comment number 39.

    #37. - newdwr54 wrote:
    "Perhaps those fond of citing the 'recovery from the Little Ice Age' as an explanation for the Arctic sea ice decline (and just about every other warming indicator) can offer an explanation for this observed increase in the rate of reduction?"
    My own view is not that this is part of the recovery from the "Little Ice Age", but part of a long-term decline in ice cover since the last "real" ice age, when Britain was covered in ice several miles thick.
    I ask a question I have asked before, is it a bad thing that Britain is no longer covered in ice?

  • Comment number 40.

    Right - so what happened to the alarmist predictions whereby the UK was going to be having milder winters and warmer drier summers al because of global warming?

    I daresay they have made yet another U-turn on that one or deny ever having said it

  • Comment number 41.

    #33 Quake is still worried about Arctic ice cover. Small ocean current changes will introduce warmer water under ice which, as you state, melt the ice from below. The ocean current changes are probably tied to the ENSO and nothing to do with human induced climate change. Our satellite records of Arctic ice cover are from 1979,towards the end of a slight cooling period which spawned reports of a new ice age so some summer ice reduction would be expected since then. Records from Captain's logs pre79 show 1940 to have little summer ice, though obviously this was not observation of the whole Arctic. Any observational data has problems and the satellite data of Arctic ice is no exception. If melt ponds are reported as clear water then data is skewed and unreliable as are the model outputs upon which alarmists cling to for life.
    Antarctic sea ice is increasing, actually quite significantly, so as the north warms the south cools which is part of the natural cycles not some apocalyptic disaster claimed, if indeed the southern sea ice was actually reported.

  • Comment number 42.

    #41, "Antarctic sea ice is increasing, actually quite significantly"

    Antarctic sea ice is currently 0.5 million sqkm above average. Arctic sea ice is 2.4 million sqkm below average.

    Another 0.5 million sqkm gain in the Antarctic will be a non-event. Another 2.4 million sqkm gain in the Arctic will mean no ice left. That is the reason why people are paying more attention to the Arctic.

    "If melt ponds are reported as clear water then data is skewed and unreliable as are the model outputs upon which alarmists cling to for life."

    Like I said there are no melt ponds now, it's too late in the season for that. The satellite measurements are fine. They'd have to be inconceivably inaccurate for 2012 to not be a record low. The research ship healy has managed to reach 83N. Visible satellite images show the ice retreat this summer:
    http://rapidfire.sci.gsfc.nasa.gov/imagery/subsets/?mosaic=Arctic.2012245.terra.4km

    "Small ocean current changes will introduce warmer water under ice which, as you state, melt the ice from below. The ocean current changes are probably tied to the ENSO and nothing to do with human induced climate change."

    ENSO doesn't fit the pattern of ice decline.

  • Comment number 43.

    20th century arctic ice extent with 20th century El Nino activity compiled by a programmer in a comment over at WUWT:
    http://www.pictureshoster.com/files/pjs0sdkl4se16f2ffv.png

  • Comment number 44.

    36.newdwr54 wrote:-

    "The only thing that would reverse this is a sudden and sustained reduction in global surface temperature rise and ocean heat content.

    No sign of that as yet."

    Apart from the sign given by the 30 year global surface temperature 30 metrics that are showing sustained and significant reductions in the temperature rise?

  • Comment number 45.

    #36. - newdwr54 wrote:
    "The only thing that would reverse this is a sudden and sustained reduction in global surface temperature rise and ocean heat content.
    No sign of that as yet."
    I would argue that there has been a reduction in surface temperature rise, even if no actual reduction in temperatures, since at the very least, there has been no significant warming for at least 10 years.
    Even the UAH 10 year trend has fallen from 0.41c/decade in 2002 to about 0.05c/decade currently.
    Of course, it all depends on what you mean by "sustained", but it doesn't have to be "sudden", since it has already underway.

  • Comment number 46.

    The last para above should read:
    Of course, it all depends on what you mean by "sustained", but it doesn't have to be "sudden", since it *is* already underway."

  • Comment number 47.

    @ 34. ukpahonta
    Thanks, I had not seen the POAMA model update. The MO did cool their ENSO prediction for 20th Aug, you can compare by clicking back to July in the link you provided.

    Lots of mixed signals re El Nino/La Nina we will just have to wait and see.

    Re MO Decadal Forecasts I have not looked for awhile, I think the MO said the first one was made in 2005 so due for completion 2015? I need to check back what data I have. Maybe QV can help?

    I have tried to get the MO to update their Decadal Forecasts on a regular basis as and when data becomes available, ideally monthly, if not then at least annually. However no joy, they insist that any forecast must be allowed to run its full course before being reported upon.

    To a certain degree I understand their reasoning, why have numerous inquests when you can make do with one? And at the end of the day they are Decadal Forecasts, not monthly or annual.

    However I cannot help feeling that if the Decadal Forecasts, the ones that are running, (I believe they are run annually) were on target or underestimating actual global temps then we would be seeing regular updates, but that must only be seen as pure supposition on my behalf. Hey ho!

  • Comment number 48.

    The UAH anomalies for August are as follows:
    Global = 0.34c, compared to 0.28c for July.
    N.H. = 0.38c, compared to 0.45c for July.
    S.H. = 0.31c, compared to 0.11c for July.
    Tropics = 0.26c, compared to 0.33c for July.
    The global figure is slightly higher than I would have expected from the AQUA CH5 figures.
    After adjustment to 1961-90, the global figure is equivalent to 0.593c, but UAH has been running above HadCRUT3 for a few months. The actual HadCRUT3 figure suggested by AQUA CH5 would be about 0.475c, compared to 0.446c last month.
    Quite a big increase in the S.H. anomaly, which brings it almost level with the N.H. value.

  • Comment number 49.

    44. greensand wrote:

    "Apart from the sign given by the 30 year global surface temperature 30 metrics that are showing sustained and significant reductions in the temperature rise?"

    That's *not* the case GS. Using a thirty year metric (like the WMO says we should) then the rolling 30 year trend is currently +0.16C (+/- 0.01C) per decade in *all* the data sets we have, including satellite.

    Taking NASA as an example, the current rolling 30-year trend is +0.17C per decade; the average rate of rise in that period is +0.13 C per decade with a minimum of +0.03C and a maximum of +0.18C. In a few months with an El Nino expected, it is likely to rise to +0.18C per decade again, or perhaps higher. So the current rate is showing no sign of any significant slowdown.

    Regarding rolling average 30 year temperatures: these are going up slowly but relentlessly, month by month, with very few exceptions. This is the case in every data set we have.

    Take UAH satellite for example. UAH hasn't been around that long, so its first 30 year 'rolling average' starts in November 2008. At that point the anomaly value was -0.026C (i.e. the average temperature between Dec 1979 and Nov 2008 was -0.026C below the UAH anomaly, which is calculated from 1981-2010).

    The rolling 30 year average then steadily rose, apart from a brief period in late 2010/early 2011, and is currently +0.015C. I would be willing to bet that it will rise again once August 2012 is added. (UAH has not yet, at time of writing, released the August 2012 data.)

    No doubt QV will be able to check and verify (or dispute!) the above. But the suggestion that surface temperature data are showing "sustained and significant reductions" is just not borne out by the evidence.

  • Comment number 50.

    Just to make a liar of me, the minute I posted the above I checked UAH and, lo and behold, it's been updated.

    August 2012 was +0.34C above the 1981-2010 average for August in UAH. It becomes the 3rd warmest August in the UAH record. And yes, the rolling 30 year average has moved from +0.015C to +0.016C. But I didn't, I promise, know that before I posted the above!!

  • Comment number 51.

    49. newdwr54 wrote:

    "That's *not* the case GS."

    Sorry DW but it is!

    GISS 30 year monthly rolling rate of warming peaked in Dec 2003, since then it has reduced by approx 8.5%.

    HadCRUT3 peaked at the same date and is presently some 20% below its peak recorded date.

    This cannot happen unless the rate of global warming is reducing. The peak warming 30 year rolling monthly happened in Dec 2003 some 8 years ago.

  • Comment number 52.

    #50. - newdwr54 wrote:
    "And yes, the rolling 30 year average has moved from +0.015C to +0.016C. But I didn't, I promise, know that before I posted the above!!"
    I don't believe you!
    You saw my post and checked it first!
    (only kidding!)
    I am a bit behind in my calcs, but I am sure that you are correct about the 30 year trends (it's good to see you are calculating rolling trends).
    However I don't think that a 30 year trend is ever going to show a "sudden" change in the trend, in the same way as a 10 year trend will.
    From what I can tell, the WMO recommended 30 year period is for the calculation of "normals", not trends and even so, it is entirely arbitrary. Actually I consider it too short for the calculation of "normals", and I prefer at least 100 years, if available, using the median rather than the mean.

  • Comment number 53.

    So much of the surface station data from years gone by has been 'adjusted' it's difficult to have much faith in the stats.

  • Comment number 54.

    no global warming detected for 14 years

    no sign of the predicted milder winters, warmer drier summers in the uk

    no sign of any increase in major storm events (their latest alarmist bodyswerve now that warming has ceased)

    lots of increases in green taxation

    you dont have to be a rocket scientist to see whats happening

  • Comment number 55.

    Regarding trend periods and the WMO, I quote from this interview with Michel Jarraud, Secretary General of the WMO:
    "So you see the trend is continuing but at the same time we have a lot of variability, natural variability, so this trend is a trend on top of the variability so you cannot look at individual years to look at the trend you need to look at long enough periods. At WMO we tend to recommend that we look at ten, or for some applications thirty year, averages to be able to look at this long-term trend. But the long-term trends are clear. This decade, the last decade, which finished this year is the warmest ever."
    http://www.rtcc.org/climate-change-tv/unfccc-videos/michel-jarraud-world-meteorological-organization/
    It actually classifies a 10 year average as a long-term trend.
    Clearly the concept of 10 year rolling trends hasn't yet reached the WMO.

  • Comment number 56.

    #54. - openside50 wrote:
    "you dont have to be a rocket scientist to see whats happening"
    Don't you mean "climate scientist? :)
    Actually "rocket science" isn't all that complicated, not as complicated as "climate science" at any rate.
    Very predictable Newtonian physics. If we could predict the climate as accurately as we can predict the velocity and motion of a rocket, we wouldn't have a problem.

  • Comment number 57.

    true quaeso - rocket science is hard science - 1+1=2 is hard science

    'it might do this or it might do that' is pseudo science

  • Comment number 58.

    Imagine if James Hansen was in charge of doing the calculations for putting Curiosity on Mars?

  • Comment number 59.

    It would of been abandoned due to polluting of the Martian atmosphere!

  • Comment number 60.

    51. greensand wrote:

    "GISS 30 year monthly rolling rate of warming peaked in Dec 2003, since then it has reduced by approx 8.5%."

    GS, just to be clear, I'm using the GISS data as published here: http://data.giss.nasa.gov/gistemp/tabledata_v3/GLB.Ts+dSST.txt

    It's the combined 'Land-Surface Air and Sea-Surface Water Temperature Anomalies'. You may be using one of the other sets found here:

    http://data.giss.nasa.gov/gistemp/

    I've checked it again. In Dec 2003 the 30 year rolling trend (i.e. from Jan 1974-Dec 2003) was +0.18 C above per decade. If you want to delve into thousandths of a degree or more, then it was +0.1798 C.

    As far as I can see this value was surpassed several times. October 2005, at +0.1806 per decade is the highest I can see, and has yet to be exceeded, so far. If this is wrong then anyone with access to that NASA data and a spreadsheet can point it out to me.

  • Comment number 61.

    52. QuaesoVeritas:

    "From what I can tell, the WMO recommended 30 year period is for the calculation of "normals", not trends and even so, it is entirely arbitrary."

    I share your confusion over what the WMO means.

    "...I prefer at least 100 years, if available, using the median rather than the mean."

    I think 100 years is too long. I think it loses its dynamic effect over that time-scale, because most of the climate variables (cycles) that we know of operate on scales much shorter than that.

  • Comment number 62.

    #61. - newdwr54 wrote:
    "I think 100 years is too long. I think it loses its dynamic effect over that time-scale, because most of the climate variables (cycles) that we know of operate on scales much shorter than that."
    I would have thought that would be an advantage as far as as establishing a "normal" figure was concerned. The last thing you need is a constantly changing "normal" figure.
    It's like establishing the "normal" temperature of a human body, by including periods of illness, such as a fever.

  • Comment number 63.

    @60. newdwr54 wrote:

    "If you want to delve into thousandths of a degree or more, then it was +0.1798 C."

    Will not argue I have it at +0.0179C

    Last number Aug 82 to Jul 12 +0.0164, 8.5% below Dec 2003

    As we have a difference and I can be a bit Phil Jones with Excel I have checked Oct 2005 at WfT:-

    "#Least squares trend line; slope = 0.0177609 per year"

    http://www.woodfortrees.org/data/gistemp/to:2005.83/last:360/trend

    and their last GISS LOTI is:-

    "#Least squares trend line; slope = 0.0163835 per year "

    http://www.woodfortrees.org/data/gistemp/last:360/trend

    I am not saying I am correct, far from it, only that I have tried to obtain confirmation from another source.

    Also I cannot see how a flat line or reduced increase in global temps can produce an increasing trend, it is just not possible.

    Anyhow I will go away and check again as the chart I have does not show that the Dec 2003 rate has been exceeded, by either GISS or HadCRUT 3 or 4 that is, as far as 4 goes.

 

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