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Increase In UK Temperatures Largely Due To Increase In Sunshine Hours – (Caused By Reduced Pollution)

December 24, 2014
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By Paul Homewood   

 

Further to my post, “Has Increased Sunshine Caused UK Warming In Late 20thC?”, the Met Office published a study of UK Climate Trends, called Climate Memorandum 21, which looked at gridded datasets of temperatures, rainfall etc.

The paper, published in 2006 and including data up to 2004, had this to say about sunshine hours.

 

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They also show this table for how all of the variables correlate together. As I understand it, (and advice from proper statisticians would be welcome!), the maximum value of the co-efficient r is 1.0, and a value over 0.50 is regarded as strong. (Negative values are equally strong).

 

 

 

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As the report spells out, the most significant correlation with maximum temperatures is in spring and autumn. It is also relevant that minimum temperatures are also strongly positively correlated in those seasons; in other words, minimum temperatures tend to be higher when sunshine hours are high.

There has in fact been little trends in winter temperatures, which leads to the assumption that the increase in sunshine hours then has been largely irrelevant. But both autumn and spring show sharp temperature rises.

Spring in particular has seen the biggest rise in mean temperatures in the last three decades in England.

 

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http://www.metoffice.gov.uk/climate/uk/summaries/actualmonthly

 

The season has also seen a steady rise in sunshine hours over the same period. Although there is evidence of a cycle, sunshine hours in the last couple of decades have been at consistently higher levels than in the previous high point of the cycle in the 1940’s (It is also worth noting that the high point of 551 hours in the very first year was the spring of our old friend 1929. You may recall that this was the most extreme year on record for rainfall, with the driest January to September on record, followed by the wettest October to December.)

 

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If we put the two datasets together, for sunshine and temperature, using 5-year running averages, we get a very good correlation, just as the Met Office paper suggests.

 

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http://www.metoffice.gov.uk/climate/uk/summaries/datasets 

 

One further thing stands out. If the increase in sunshine hours was purely a meteorological phenomenon, i.e more high pressure, we would expect rainfall to be significantly lower. There is, however, no evidence of this.

 

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Conclusion

We have established that :

1) Sunshine hours in spring began rising in the 1980’s, and are now at higher levels than seen previously on the record since 1929.

2) According to Met Office scientists, this increase “could be the result of the Clean Air Acts of 1956 onwards”, a theory supported by “the greatest increase in sunshine hours being in the north of England, notably in and downwind of major conurbations”.

3) The Met Office find strong, positive correlation between sunshine hours and both max and min temperatures during spring and autumn, the seasons when most of the temperature increase in the UK has occurred in the last 30 years.

4) 5-Year trends for mean temperatures and sunshine hours also appear to be strongly correlated back to 1929

 

In other words, there is strong evidence that much of the temperature increase seen in England in the last three decades, which has commonly be simply written off as due to “global warming”, is instead a product of increased sunshine, likely caused by reduced air pollution.

I find it absolutely astonishing that the Met Office and others have, more or less, ignored this whole issue, and not seriously investigated it further.

 

 

Finally let me wish you all a very happy Xmas and prosperous New Year.

12 Comments
  1. December 24, 2014 7:58 pm

    “I find it absolutely astonishing that the Met Office and others have, more or less, ignored this whole issue, and not seriously investigated it further.”

    If they know ‘the solution’, how on earth could they justify asking for a new toy, a bigger number-cruncher?

    ————————————————————————————

    On a lighter note, I bet you’re under strict instructions to post nothing tomorrow!

  2. saveenergy permalink
    December 24, 2014 8:06 pm

    Thanks Paul & same to you, have a well deserved rest & hope Santa doesn’t get mugged on t’wicker.

  3. December 24, 2014 8:19 pm

    Thanks very much for all your hard work and very informative posts. All the best.

  4. catweazle666 permalink
    December 24, 2014 9:34 pm

    “I find it absolutely astonishing that the Met Office and others have, more or less, ignored this whole issue, and not seriously investigated it further.”

    I don’t.

    And I bet you don’t either!

    Happy Christmas, Paul!

  5. December 25, 2014 12:56 am

    Can anyone show that CO2 can increase the lapse rate at all? There is no absorption of IR flux with every location in the atmosphere at a temperature higher than that needed for radiative equilibrium. This higher temperature via latent heat conversion means no actual altitude for exit flux. The flux outward to space continues to “accumulate” all the way to 220 km. Increasing atmospheric CO2 can have no effect on temperature at the surface or troposphere, and can only increase exit flux from the stratosphere, cooling it. It is the purpose of the atmosphere, not the surface, to regulate, via adjustable water vapor content, the temperatures, on or about this planet.
    Merry Christmas and Happy New Year! 🙂

  6. John F. Hultquist permalink
    December 25, 2014 2:21 am

    I searched (Bing) using ‘ smog air_quality england 1950s ‘ with the IMAGES tab. Do not use ‘air’ alone or you get the shoes with that as part of the name. There are many fantastic old photos.
    Then, try it by replacing England with Pittsburgh, PA or other city you know of. The nearby town of Donora made the news in 1948 for a smog that killed people. Afterward, the city, state, and Feds got serious about cleaning up the air. I lived 2 hours north of Pittsburgh and (for years) the paper and TV (black & white) (our first in 1954) carried frequent stories of the air quality and improvements thereof.
    In those years there was much home heating with coal and wood. We switched from coal to gas about that time.

    The first Christmas dinner with turkey that I can remember was cooked in a gas oven.
    Merry Christmas!

  7. Bloke down the pub permalink
    December 25, 2014 1:08 pm

    I find it absolutely astonishing that the Met Office and others have, more or less, ignored this whole issue, and not seriously investigated it further.

    Or more likely, having investigated, decided to bury what they found as there’s no money left in the ‘reduce smog’ pot.

    • Bloke down the pub permalink
      December 25, 2014 1:11 pm

      Merry Christmas to one and all. If I’d stayed off the sherry I’d have remembered to put this in the main comment. Hic.

  8. December 26, 2014 9:36 am

    Eccoterrorists demand more pollution?

  9. December 26, 2014 11:26 am

    Paula says
    The Met Office find strong, positive correlation between sunshine hours and both max and min temperatures during spring and autumn, the seasons when most of the temperature increase in the UK has occurred in the last 30 years.

    Henry says

    but it seems to me all global sets show strong warming from the 1970’s onward, until around 2000.
    http://www.woodfortrees.org/plot/hadcrut4gl/from:1987/to:2015/plot/hadcrut4gl/from:2002/to:2015/trend/plot/hadcrut3gl/from:1987/to:2015/plot/hadcrut3gl/from:2002/to:2015/trend/plot/rss/from:1987/to:2015/plot/rss/from:2002/to:2015/trend/plot/hadsst2gl/from:1987/to:2015/plot/hadsst2gl/from:2002/to:2015/trend/plot/hadcrut4gl/from:1987/to:2002/trend/plot/hadcrut3gl/from:1987/to:2002/trend/plot/hadsst2gl/from:1987/to:2002/trend/plot/rss/from:1987/to:2002/trend

    Are you saying now that we are all polluting the earth less? What about China and India? How then do we start explaining the global cooling trend since 2002?

    I am not excluding the possibility that some physical dirt (soot, etc) in the atmosphere may affect sunshine hours on earth a little bit. However, I am not sure how big such an effect could be and how do we measure it? When you count sunshine hours, is the strength of sunshine hours taken into account?

    No, it seems more likely that warming and cooling periods can be directly linked to the cycles governing the magnetic field strengths from the sun. The magnetic fields strengths from the poles of the sun are now at their lowest. Hence we entered a cooling period. My graphs clearly show that global warming will not come back for quite some time….

    http://blogs.24.com/henryp/files/2013/02/henryspooltableNEWc.pdf

    Be careful in paying too much attention to those who keep beating on the global warming drum, i.e. Metoffice, Bester, etc [For their own gain], they will continue to refuse to admit that everything is controlled by cycles.

  10. Doug Proctor permalink
    December 27, 2014 4:58 am

    Paul, I disagree with the conclusion of the Met Office because they only “explain” the post-1956 changes (clean air acts) while admitting there was a post-1930 change.

    The work I did and they work they did shows the two cycles, though with a continuing warming trend, from 1930 to 2010. There is the down-cycle between the two as I noted; this the Met Office did not explain either, as if somehow the air got worse after it had initially gotten better.

    Their coefficient “r” is as true when there is a non-causitive correlation as there is when there is a causitive connection, keep in mind.

    If Slingo could say that the “pause” is due to her government’s green policies, then the Met Office can say there were not less natural clouds but less air pollution. Both fit the facts, like curve-fitting can always explain the past.

    Perhaps temperatures really do rise and fall with piracy – lots before WWII, not so much during WWII and lots afterwards, particularly since the 1970s. The correlation is pretty good.

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