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April 2011. Warmest since 1659. Update

Paul Hudson | 06:39 UK time, Sunday, 1 May 2011

UPDATE on Tue 3rd May

Bradford Lister Park, with records back to 1906, has also recorded its driest (previously 2007) and warmest April (previously 1966) on record, and its sunniest (previously 1942).

New records too (for lowest rainfall) at Linton on Ouse and Church Fenton.

ENDS

Figures released by the Met Office next week are expected to show that April 2011 has been the warmest ever recorded according to Central England Temperature (CET) records, which is the longest temperature data set in the world, with records going back to 1659.

The April record was last set only 4 years ago in 2007; before that the previous warmest April on record was in 1865.

It continues a run of incredible temperature extremes, coming hot off the heels of December 2010 which was the second coldest December since 1659, and the coldest since 1890.

Locally, April 2011 will also be the warmest on record at Leeming in North Yorkshire.

April 2011 will also not only be the driest April on record at the North Yorkshire station, but their driest month ever, with less than 2mm for the entire month.

The previous driest April was in 1954 (5.4mm); and the previous driest month was February 1985, with 2.9mm of rain. Records go back to 1945.

Comments

  • Comment number 1.

    Farmers here in the Yorkshire Wolds are desperate for some rain for their crops, they reckon they have never known a Spring like it, which is rather backed up by these figures from Leeming.

  • Comment number 2.

    This shows the kind of extremes of temperature persistent blocking systems can cause. Mobile westerlies produce a much less extreme run of maritime type temperatures, and the lack of them is particularly notable.
    If this blocking type holds the summer could be like 1976, but I'm doubtful the pattern will hold that long; rain is probably on the way this summer. Even so this may be too late to stop damage to crops this year, rain is vital during the early growing stages and keeps disappearing in the forecasts.
    It's been a busy spring for extreme weather, most notably the tornados of SE USA. The warmists are falling over themselves to fall onto these stories with almost God-fearing zealotry, but before that disinformation spreads like an oil slick across this blog I'll put in my two penneth.
    These events are classic of cold PDO / negative ENSO patterns and despite media reports there is absolutely NO trend in F3-F5 tornados over the last 50 years, similarly there is NO increase in temperature of the SE US in that period. The widely reported increase in number of tornados in the last 50 years is a huge increase in F0 and F1 being reported because of greatly increased reporting ability with Doppler radar development.
    As usual we are seeing that weather is not climate until it reinforces the message you want to push, in which case it is. This does apply to both sides of the discussion, and can only be countered with cold facts untainted by speculation.

  • Comment number 3.

    I have got used to planning my holidays in the UK for April and May, purely because they have been so much nicer recently than traditional summer months. You don't get the humidity but the sun is strong.

    Back to the blog, Paul you must be aware that the CET record is not complete or thorough once you go back more than about 100 years. It was pieced together by guesswork and averaging. It is a very weak piece of work that should not be relied on for deciding if something is a record or not.

    However given that we are still on the beneficial gradual warming since we escaped the Little Ice Age (that Mann-made Global Warmists tried to wipe out of the record), it should be no surprise that we have the odd warmer month from time to time.

  • Comment number 4.

    No-one tried to wipe the little ice age out of the record. I agree the world is still warming though, I just don't think nature is contributing to it anymore. I think if it wasn't for humans temperatures would have probably cooled since the 1950s.

  • Comment number 5.

    Quake @ 4 "I think if it wasn't for humans temperatures would have probably cooled since the 1950s."

    In that case fire up the Quattro - excessive cold kills 10x more people than excessive heat in this country, and I for one am very glad we aren't slipping back into a full Ice Age just yet. Unfortunately with the AMO turning negative in the next decade or so, and 25 years of cold PDO to still live through I think we had better get used to this cooler weather type.

  • Comment number 6.

    Updating the rainfall data for Wheldrake (S E fringe of greater York):
    March...........6 mm (13% of average), April............. 1 mm (2.5% of average)
    Year to end of April...113mm (63% of Jan to April average)

    David Randon

  • Comment number 7.

    millenia/pingosan

    I don't think anyone is pushing any "message" (would they dare!).

    It's just that this April has been astoundingly warm and astoundingly dry. Whether or not you choose to believe this really is a record, or has any greater significance is entirely up to you.

    However there is no denying it has been remarkable.

  • Comment number 8.

    "It's just that this April has been astoundingly warm and astoundingly dry"

    We know from experience that the global warming ideologue idiots will pounce on any weather extreme. Despite the globe having cooled in the last few years. Despite their Mann-made-up "evidence" being fraudulently obtained.

    The majority of the "Green" commenters on this blog have already been exposed as being in the pay of Big Renewables.

  • Comment number 9.

    Around the turn of the year, I remember there was talk of setting up some sort of long range forecasting competition/comparison between the met office and other major players.
    I presume the last couple of months has buggered them all up!

    Pingosan - I wasn't aware of that 'Big Renewables' connection - are you sure? I'm reasonably new to the blog and had just assumed that most of the 'Green' commentors were just expressing personal opinions.

  • Comment number 10.

    "Despite the globe having cooled in the last few years"

    Well actually, it hasn't.

  • Comment number 11.

    Quake. It is funny that you still believe in Global warming by man, when all the evidence coming out suggests that it has been caused by the sun and that the planet is currently going through a cooling phase. Can I just check that you are actually on Earth and not another planet in the universe?

  • Comment number 12.

    Quake,
    I too think global temperatures have shown a cooling trend over the past 8-10 years.
    Is this the time scale you are looking at?
    If so which database?

  • Comment number 13.

    "Despite the globe having cooled in the last few years"

    Well actually, it hasn't.
    ------

    Quake, I suggest you look at the latest satellite temperature measurements. Either you are misinformed, or lying - which is it?

  • Comment number 14.

    Pingosan. I think Quake is living on a different planet or in a parallel universe.

  • Comment number 15.

    I am more than familiar with both UAH and RSS satellite temperature records Pingosan. Care to explain just how you are interpreting cooling?

  • Comment number 16.

    3 Months of below average global temps = years of cooling.

    Don't you understand Quake?

    :-)

  • Comment number 17.

    I am surprised that the M.O. hasn't yet issued a news release, blaming this on "climate change".
    Maybe it's because the global temperture as a whole is relatively low.

  • Comment number 18.

    #10. - quake wrote:
    "Well actually, it hasn't."

    Of course it depends on your timescale, but based on 10 year linear trends:

    HadCRUT3 -0.678c per century and falling.
    RSS approx -0.5c per century (not sure of the exact figure) and falling.
    NCDC -0.21C per century and falling.
    UAH +0.36c per century and falling.
    GISS +0.45c per century and falling.
    Verification of this can be obtained from the Climate4you website.
    http://www.climate4you.com/
    UAH will be negative by July and probably GISS by the end of 2011.
    All 10 year trends are likely to stay negative until about 2020.
    20 year linear trends are likely to become negative around 2016.

  • Comment number 19.

    1) The skeptics' temperature dataset of choice, the UAH satellite record shows a positive trend no matter which year the trend starts in. So if skeptics were at all consistent they wouldn't believe the world was cooling, let alone be so confident it was.

    2) The skeptics decry HadCRUT3 because of who authors it and because it is based on surface stations which skeptics regard as full of uncertainties. So something rather odd is happening for skeptics to be basing their beliefs on whether the world is warming or cooling on HadCRUT3. Especially given point #1.

    3) Skeptics made a big play over Phil Jones saying there had been no statistically significant warming since 1995 in HadCRUT. Phil Jones meant at the 95% level, there's actually a trend of 0.96C per century warming since 1995 in HadCRUT, it's just not quite at the 95% significance level. Skeptics however spin his words to conclude "there's been no global warming since 1995" and there's been quite a few repetitions of this claim in comments on this blog in past months.

    4) There has been about -0.65C per century cooling in HadCRUT3 since 2001 and skeptics will cite this as evidence "the world is cooling". But not only do I believe this contradicts their dismisal of hadcrut3 (point 2), and their avoidance of UAH (point 1), but also by making this claim skeptics are contradicting themselves with regard to point 3. If 0.96C per century warming since 1995 is insignificant, then how on earth can 0.65C per century cooling since 2001, a shorter period, be significant? How can skeptics conclude from the former that the world isn't warming but state the world is definitely cooling from the latter?

    5) The idea that the satellites show the globe cooling is not only false (above), but has nevertheless been so ingrained into skeptics that they believe it to be so true that anyone (eg me) contradicting the claim obviously doesn't know what they are talking about!

    The only interpretation of the above facts is that skeptic blogs have (and I don't use this phrase lightly) brain washed their readers into believing the world is cooling based on a staggering level of cherrypicking records and statistical techniques based on whether the answer they produce is what they want to hear. Ultimately it probably owes more to repeating "the world is cooling" so much without reference to any data that people actually start believing it's true.

    This isn't aimed at QV, whose post is correct and is citing the actual numbers (althouh I disagree about the last part)

  • Comment number 20.

    19. quake:

    Well summarised. The fact that the UAH record effectively supports most of the major observations of GISS appears to be an affront to many 'sceptics'.

  • Comment number 21.

    PingoSan wrote:

    [8.] "Despite the globe having cooled in the last few years.... [13.] I suggest you look at the latest satellite temperature measurements."

    Can you be more specific with dates please? I've looked at both UAH and RSS from 1998 to present. Every linear trend line I add to the data from then until now is upward with the possible exception of 2002-present in both sets, which is flat-line at best.

  • Comment number 22.

    HadCRUT3 -0.678c per century and falling.
    RSS approx -0.5c per century (not sure of the exact figure) and falling.
    NCDC -0.21C per century and falling.
    UAH +0.36c per century and falling.
    GISS +0.45c per century and falling.

    So if I read this correctly three out of five show cooling - the remaining going negative later this year. What excellent news, well done everybody we've won! Perhaps we can now start spending money on more useful things instead of on the current 15:45 Express to Gravy Central.

  • Comment number 23.

    nibor25,

    This shouldn't be seen as proof that "global warming" doesn't exist, only that the long-term rate is lower than the last 30 years would suggest, i.e. less than 1c per century. I believe that it is entirely consistent with a downward cycle in an otherwise upward trend of about 0.8c per century.

  • Comment number 24.

    PWS were way out with their forecast for April, giving no hint of such a dry and warm spell. March was wrong too. Another one conveniently swept under the carpet?

  • Comment number 25.

    22. nibor25:

    UAH's own published decadal trend is +0.14C: http://vortex.nsstc.uah.edu/data/msu/t2lt/uahncdc.lt (Second row from bottom of page).

  • Comment number 26.

    #19 - quake wrote:
    "1) The skeptics' temperature dataset of choice, the UAH satellite record shows a positive trend no matter which year the trend starts in. So if skeptics were at all consistent they wouldn't believe the world was cooling, let alone be so confident it was."
    I suspect that if sceptics have a preference for UAH, may be based on a lack of understanding of the base periods involved. The UAH anomaly was generally lower than HadCRUT3 and GISTEMP, because it was relative to 1979-98, compared to 1961-90 for HadCRUT3 and 1951-80 for GISS. Since the base period for UAH was changed to 1981-2010, of course, the anomalies have been even lower. However, when adjusted to the same base period, there is virtually no difference between HadCRUT3 and GISTEMP and UAH. In fact, since 1976, GISTEMP is marginally lower than UAH and about 0.15c lower than UAH over 2010. This may not be popular with other sceptics, but you have to accept the facts. However, this does not stop me being sceptical about exaggerated rate of warming based on the last 30 years, and biased climate models. My belief is that those who developed he models were mislead by doing so during a period of higher than average cyclical warming.
    Regarding the last part of my post, it is based on identified cyclical patterns, which may or may not continue. However it is entirely consistent with those cyclical patterns, until there is evidence that they are not continuing.

  • Comment number 27.

    #25 - newdwr54 wrote:
    "UAH's own published decadal trend is +0.14C: "
    Since the figures quoted by nibor25 were from my post, I feel I should respond.
    Do you have any info on how that trend is calculated?

  • Comment number 28.

    Is it my imagination or are the temperature anomalies shown on this map less extreme than they usually are?
    http://www.coaps.fsu.edu/%7Emaue/extreme/gfs/current/raw_temp.html
    There don't seem to be as many lurid orange areas in the Arctic as usual and, there appears to be a prediction of below normal temperatures over large parts of Europe and the U.S. over the next few days.

  • Comment number 29.

    27. At 18:44pm 2nd May 2011, QuaesoVeritas wrote:

    "Do you have any info on how that trend is calculated?"

    I don't know exactly, but I understand it is derived from a straight line model, based on the 'least-squares fit' statistical equation. I assume there is an appropriate formula that can be applied to the data on a spreadsheet, but I don't know what it is.

    I have tried to emulate their 0.14C per decade trend on Excel by using 10 year averages, but the closest I can get with this method is a trend of +0.18C per decade. Pride prevents me from asking the children. If anyone knows, I'd be very interested in learning this.

  • Comment number 30.

    28. QuaesoVeritas:

    Arctic Sea ice melt is slower this season than of late: http://nsidc.org/data/seaice_index/images/daily_images/N_stddev_timeseries.png

    Possibly connected to La Nina?

  • Comment number 31.

    #29 - newdwr54 wrote:
    "I don't know exactly, but I understand it is derived from a straight line model, based on the 'least-squares fit' statistical equation. I assume there is an appropriate formula that can be applied to the data on a spreadsheet, but I don't know what it is."
    No doubt it is in a FAQ or readme file somewhere, I will have to do some searching.
    I can't even see where it says it's a decadal trend.
    Without the method of calculation, it's a bit meaningless.


  • Comment number 32.

    #30 - newdwr54 wrote:
    "Arctic Sea ice melt is slower this season than of late: http://nsidc.org/data/seaice_index/images/daily_images/N_stddev_timeseries.png

    Possibly connected to La Nina? "
    I must admit that I haven't studied sea ice extent much, but since temperatures are generally lower, and that is attributed to La Nina, it seems likely.

  • Comment number 33.

    31. QuaesoVeritas:

    It used to say 'd', signifying 'decadal' but this was removed around about the time they changed the anomaly baseline. It's a year old post now, but Spencer confirms 0.14C as a decadal trend here: http://www.drroyspencer.com/2010/05/april-2010-uah-global-temperature-update-0-50-deg-c/

  • Comment number 34.

    Here's a better link to UAH's decadal trend for the lower troposphere (currently 0.138 C). Still no idea how they arrive at that figure: http://vortex.nsstc.uah.edu/data/msu/t2lt/tltglhmam_5.4


  • Comment number 35.

    #33 - newdwr54 wrote:
    "It used to say 'd', signifying 'decadal' but this was removed around about the time they changed the anomaly baseline. It's a year old post now, but Spencer confirms 0.14C as a decadal trend here: http://www.drroyspencer.com/2010/05/april-2010-uah-global-temperature-update-0-50-deg-c/"
    Thanks, that makes more sense. I was doing the trend over the last 10 years, but the above post says since 1979.
    I have calculated the linear trend over the whole series since January 1979 and it comes to 0.00114555c per month, multiplied by 120, equals 0.137466c per decade, rounded to two places = 0.14c per decade. The rounding would explain why the trend hasn't apparently changed for a year. As more data are added to the series, the trend would become less likely to change from month to month. It would take huge recent changes to change the long-term trend significantly. My figure of +0.36c per century, or +0.036c per decade, is based on the last 120 months. I prefer to calculate rolling trends over various periods as this gives an insight into how the trends are changing over varioius periods of time, and in some cases this reveals long-term cyclical patterns which are not normally apparent.

  • Comment number 36.

    35. QuaesoVeritas:

    Your figure fits perfectly with the full UAH one. It's very satisfying to know how that was worked out. Well done you! I'll apply it to the other sets now and see what comes out.

  • Comment number 37.

    #36. - newdwr54 wrote:
    "Your figure fits perfectly with the full UAH one. It's very satisfying to know how that was worked out. Well done you! I'll apply it to the other sets now and see what comes out."
    I thought it was a team effort!

  • Comment number 38.

    Using UAH's trend analysis (average temperature change per decade from 1979) all the data sets show fairly good agreement.

    UAH +0.14
    HadCRUT3 +0.16
    GISS +0.17
    RSS +0.15
    NCDC +0.16

    The average is +0.15 C per decade. As QuaesoVeritas points out this has slowed right down in the last decade.

    UAH +0.09
    HadCRUT3 -0.03
    GISS +0.07
    RSS -0.05
    NCDC -0.02

    The average temperature change from 2001-2010 was +0.06 C, but three of the sets showed a slight cooling trend.

    Whether or not this last decade heralded the start of a cooling period linked to long term ocean cycles remains to be seen. The fact is it also coincided with a sustained period of reduced solar output: http://www.woodfortrees.org/plot/pmod/from:2001/plot/pmod/from:2001/trend

  • Comment number 39.

    I have worked out that in order to increase the rounded UAH trend from 0.14c to 0.15c, would require an anomaly in April of approximately +1.9c, and to reduce it to 0.13c, would require an anomaly of approximately -1.0c. This is because the longer the data series, the less effect each new value has. The same would apply, of course to other data sets.
    In my view, this long-term trend tells us little about how the trend is progressing.
    On the other hand, rolling trend calculations do show that.
    I don't know for certain if the current decline of the 10 year trend into negative territory is the start of a cooling phase, but it is entirely consistent with the apparent 60 year cyclical pattern in the 50 year linear trend, based on HadCRUT3 figures. If this pattern continues, the 50 year linear trend will fall for the next 30 years and the 10 year linear trend will continue falling until about 2014, when it will reach a rate of about -2.5c per century, then start to rise again for a while. This figure and timescale are approximate, because it is not entirely certain where we are in relation to the 60 year cycle. Clearly since this cyclical pattern is based on actual HadCRUT3 data, it MUST include all cyclical influences which have acted on atmospheric temperature in the past, including solar and oceanic. A graph of the rolling 50 year linear trend can be seen on the Climate4you.com website, under "Cyclic air temperature changes", as Ole Humlum was kind enough to confirm my calculations and post the graph.

  • Comment number 40.

    39.QuaesoVeritas:

    As you point out, it would take an enormous monthly change to increase or decrease a trend in data series' as long as those of the main temperature records.

    I don't think AGW theory anticipates or relies upon such a dramatic swing. The theory says that, all other things being equal, human greenhouse gas emissions are likely to increase global surface temperatures over time.

    The evidence in the climate record is consistent with that theory. There has been low solar output of late, so 'all other things' have not been equal. All the IPCC reports, and all the climate scientists as far as I am aware, accept that there are other 'forcings' that can influence climate - ocean cycles and insolation among them.

    Once the current La Nina phase lifts, and given slow recovery of solar input, I would expect to see temperatures steadily rise in a significant way from July 2011 onward. Of course I may be wrong.

    There is no doubt that oceanic cycles contribute to climate patterns. But I believe that the underlying upward trend cannot be fully explained by such cycles; not without taking increased greenhouse gas concentrations into account at least.

    While our views differ, I respect yours (especially in light of p. 26) and I am happy to 'agree to differ'. The truth will out, as they say.

  • Comment number 41.

    RSS have got in with their April anomaly before UAH this month, probably due to the Tornadoes hitting Alabama and power outages in Huntsville.
    The unadjusted global figure for April is +0.11c, compared to -0.027c last month.
    After adjustment to 1961-90, this is equivalent to a HadCRUT3 figure of about +0.257c, which is actually a bit lower than I had expected based on he last AQUA CH5 figures I saw before the website went down due to the Tornadoes. It corresponds to a UAH figure of about zero.

  • Comment number 42.

    #40 - newdwr54 wrote:
    "I don't think AGW theory anticipates or relies upon such a dramatic swing. The theory says that, all other things being equal, human greenhouse gas emissions are likely to increase global surface temperatures over time."
    My analysis doesn't preclude that, but all I can find is a rise of less than 1c per century, between each phase of the cycles.
    The point about the cycles is that they show that there may be periods of temperature rise above the underlying trend and below the trend. The last 30 years have been above the trend but if the cycles continue, that period is coming to an end. While it may be several decades before this becomes obvious, I don't believe that temperatures will show a significant rise over the next 10 years.
    On the other hand, I expect a rapid increase in temperatures between about 2030 and 2060, reaching an anomaly of over 1c during the late 2050's. Unfortunately, I won't be around to check!
    As you say, only time will tell, but I believe that one piece of evidence is that actual temperatures are falling behind most of the IPCC model projections.


  • Comment number 43.

    And now we have just had -10.7c last night at Shap, coldest ever May temperature?

    (well since the Little Ice Age possibly, but I see Paul didn't mention anything about the Mediaeval Warm Period!)

  • Comment number 44.

    It is not unusual in spring for there to be very large diurnal temperature ranges with a tendency for clear skies and dry air, before the more humid summer restricts large night time drops in temperature. I have only heard of -6C so far but even so as I said originally way back in comment 2 this blocking type will gives us extreme temperature ranges compared to the more steady ranges from a mobile westerly. Both record highs and record lows tend to come from clear skies and light winds and similar weather conditions, albeit with generally different air masses emphasising either the cold or warm.
    I'm going to go along with QV in that this is all about cyclical temperature changes in a general warming trend out of the LIA. If we are to go into a new LIA we won't confirm the signal until we are well into it. NOBODY can predict where the temperatures will be in 50 years, only forward project what we know about general trends and cycles within them. I think at 0.8C per century and rough projection of 0.4C warmer by mid century is neither way out there or worrying, especially when the error bars on that projection are likely to be +- 50% because of what we don't know yet about the cumulative effect of ocean and sun cycle changes.

  • Comment number 45.

    #44 - millennia wrote:
    "NOBODY can predict where the temperatures will be in 50 years, only forward project what we know about general trends and cycles within them."
    I think that you mean that NOBODY can predict them with certainty!
    There are lots of predictions, including those from the IPCC models, which are looking less and less realistic each month.
    I have to admit that my own projections ASSUME that there is no acceleration in the underlying trend, but there is currently nothing to suggest that is happening, since the "low" around 1978 was about 0.5c higher than that around 1917, and the current "high" seems to be peaking about 0.5c higher than that around 1951. Nothing is certain however, since the exact timing of the cycles isn't clear. This may be due to the variation in natural cycles, for example, solar cycles don't always fit into the neat 11 year pattern. The 50 year linear trend is still rising but not as fast as it was 12 months ago. However, if the current "high" peaks above or later than expected, I may have to throw my theory into the bin.

  • Comment number 46.

    We have an accurate temperature record from 1850. Before that temperatures were taken on poor thermometers at irregular intervals so no real meaningful record is available. Remember too, the UK is a reasonably small island off the NW coast of Europe so temperature readings from here are not indicative of the general NH temperatures.

    As a matter of interest, The southern states tornado swarm that occurred a few days ago in the US was due to cold air over the northern mid west mixing with a warm air mass from the Gulf. The northern half of the US and the whole of Canada are still recovering from a severe winter and therefore temperatures there are below the average.

    Ocean temperatures are still low and since the oceans hold most of the atmospheric heat it is here that we should be looking not the gaseous atmosphere.

  • Comment number 47.

    To the best of my knowledge, nobody, including the UKMO has suggested that the high April temperature is due to "climate change". However, they don't need to now, since the seeds have already been planted in the minds of the public and the media, so there is an underlying assumption that unusually warm and/or dry weather is the result of man made "climate change".

  • Comment number 48.

    Central England Temperature readings for England April:-
    1762 10.0C, 1783 10.0C, 1792 10.0, 1794 10.2, 1796 10.2, 1798 10.4, 1865 10.6, 1869 10.1, 1893 10.3, 1943 10.5, 1944 10.2, 1945 10.1, 1949 10.0, 1961 10.0.

    The MET Office should consider the above and not try to make a big deal of a small hand.

  • Comment number 49.

    QV @ 47
    Because of all the idiots that blamed the Japan earthquake on climate change, as well as the tornado outbreak in the US, it now unfortunately has to be the default position to get in with the debunk BEFORE somebody (and they will) points to April in the UK as more proof that we are changing the climate.
    As JM points out above, the tornado outbreak was caused by the enhanced difference between a very cold Canada and Midwest and higher than normal Gulf SST - both classic La Nina occurrances. Expect more of this in a cooling world and less in a warming one, 2010 was very warm in the US and had one of the lowest tornado numbers on record and a hurricane season with no major US landfall.
    Expect the hurricane season to be very different this year, and expect the AGW crowd to go mental at the first landfall of a CAT3+ storm in the continental US. Also do not be surprised if the UK gets a repeat of the 2007 floods this summer.
    Just remember it is COOLING causing an increased temperature gradient north to south that creates more energenic weather. AGW should cause a decrease in the gradient as the Arctic warms more rapidly and actually make storms less severe, despite all the mass media disinformation that says otherwise.
    In the end climate change has now become climate disruption to enable the AGW hysterics to claim ANY extreme event as their own - even flippin' earthquakes!

  • Comment number 50.

    @43 Pingosan

    It looks like the Shap temp might of been an error. It was showing 1.8 at midnight then -10.7 an hour later.

  • Comment number 51.

    Dear paul
    you are a refreshing change and I love you.
    but what do you think these weather pattens mean, are we in for lots of dry and hot spring weather or is this a one off,dont get me wrong I love it but my poor garden doesn,t nor does my dogs

  • Comment number 52.

    Why do some people on here criticise CET temperature data as being unreliable when there has been a warm record broken, and yet back in December, when according to CET data it was one of the coldest, those same criticisms were not sounded about that very same data set? No bias there then from climate sceptics!

  • Comment number 53.

    49. millennia wrote:

    "AGW should cause a decrease in the gradient as the Arctic warms more rapidly and actually make storms less severe..."

    But there will always be a temperature differential when Arctic air meets warm air from the southern ocean. This is especially true in spring, as the Arctic is still very cold, while the ocean air is increasingly warm. This would occur whether or not the Arctic is warming over all. It is still a very cold place relative to elsewhere.

    One key ingredient that does depend on warming is atmospheric moisture content. In addition to wind sheer, moisture is also a component part of these storm systems. There is a fair amount of moisture in the atmosphere of the southern US at present, and that is very likely to be linked to the anomalously high ocean heat content in the Gulf.

  • Comment number 54.

    Re 52, interesting though. I would like to see how the skeptic blogs report this April record, but they don't seem to be covering it so far.

    Arguably of course the 2nd coldest December since 1659 was of more note than the warmest April since 1659.

  • Comment number 55.

    54. quake:

    I am splitting hairs here, but December 2010 was the third coldest in the CET record, not the second (according to my download). 1890 and 1676 were slightly colder. I stand to be corrected.

    Your point is well made. Anyone familiar with the Daily Telegraph blogs, for example, will be aware that the usual suspects, James Delingpole and Christopher Booker, tend to increase their output of derogatory climate change posts when the local weather is cold.

    Once things warm up locally the output tends to wither like a parched nettle. Booker even hid his last comment on climate change at the bottom of an article with a completely unrelated headline: http://www.telegraph.co.uk/comment/columnists/christopherbooker/8485667/Neil-Herron-Metric-Martyr-campaigner-took-on-the-parking-enforcers-for-me.html.

    Both of these men made great play of the exceptionally, but not record, cold December; neither has yet, to my knowledge, even so much as commented on the record warm April.

    The record high April weather in the UK doesn't prove that AGW is true. The (near) record low December weather doesn't prove that it is false. All that can truthfully be said is that certain commentators are very prone to cherry-picking the information they comment on.

  • Comment number 56.

    @55 presumably that's because they have a biased view and you do not?

    I'm afraid we're all guilty of attaching more significance to events which support our own belief systems. That's just how humankind is wired. In the long term, its advantages must outweigh the disadvantages, otherwise this trait wouldn't have evolved.

    Keeping a check on this is tough for most of us. However, it is what we non-scientists unrealistically expect of good science. Skeptics like myself, sometimes wonder if objectivity was the first casualty of the AGW scare. Others go further and believe that honesty and integrity fell first. Personally, I'm not quite that cynical.

  • Comment number 57.

    #55 - newdwr54 wrote:
    "Both of these men made great play of the exceptionally, but not record, cold December; neither has yet, to my knowledge, even so much as commented on the record warm April. "
    That may have been due to the fact that we have been told by the "warmists" that winters would become progressively warmer and that snow would be a thing of the past", i.e. it ran counter to predictions.
    Since we are continually being reminded that individual months have no significance in relation to long term trends, (especially when it is cold), I fail to see what you would expect Delingpole and Booker to say in relation to April, except that unusually warm weather doesn't prove the climate is changing. Presumably you wouldn't expect them to say the opposite?


  • Comment number 58.

    I would say the skeptic blogs are far more guilty at selective reporting of weather events than other blogs or the mainstream media, and yet those skeptic blogs are the loudest and quickest at complaining that other blogs and the mainstream media are selectively reporting.

    Their selective reporting is why so many skeptics have the impression that the world is cooling.

  • Comment number 59.

    #58 - quake wrote:
    "I would say the skeptic blogs are far more guilty at selective reporting of weather events than other blogs or the mainstream media, and yet those skeptic blogs are the loudest and quickest at complaining that other blogs and the mainstream media are selectively reporting."
    The one is only in response to the other, i.e. to set the record straight.
    "Their selective reporting is why so many skeptics have the impression that the world is cooling."
    I think that most skeptics start out being "believers", but finding increasing inconsistencies in the pro-warming propaganda, turn to sceptical web sites in order to find support for their own beliefs. I don't believe that many sceptics are "converted" by sceptic blogs. On the contrary, they are converted by the obvious exaggeration and bias of the "warmist" pubicity.


  • Comment number 60.

    From personal experience I can support QVs position on this.
    My own interest in the AGW issue was sparked by a Windfarm application nearby which led me to dig around for more information, not knowing at the time whether to support or object to the proposal.
    Subsequently, I discovered how economic policy was driving the agenda for renewables rather than the science/technology itself. If britain sat on 300yrs worth of easily recoverable oil reserves, we probably wouldn't be having this discussion. Any research that even hinted at a potential problem would be dismissed as greenwash.

    The mainstream media may or may not be directed by bias at senior levels. What is for sure is that the 'sky is falling' is always a better headline than "no news today".

  • Comment number 61.

    57.QuaesoVeritas wrote:

    "....we have been told by the "warmists" that winters would become progressively warmer and that snow would be a thing of the past"

    I'm not sure that any scientific paper has predicted progressive warming in winter for the UK. Some scientist may have made unguarded remarks to this effect, but that's not the same thing as a scientific prediction. My understanding of the IPCC synopsis is that the warming trend is likely be gradual over time. Natural variations will always play a role in modifying day to day temperatures, but the long term trend should be upward.

    The point about 'sceptical' commentators, especially bloggers, is that very often they have an overtly political or economic motive for their scepticism. Often this is accompanied by a lack of any actual scientific training in this specific area. That is certainly the case with both Booker and Delingpole. So to a certain extent they have to rely on hyperbole to get their points across. They don't 'do' balanced consideration of the arguments; possibly because they don't fully understand them.

    But that doesn't stop them forming firm opinions.

  • Comment number 62.

    60. lateintheday wrote:

    "I discovered how economic policy was driving the agenda for renewables rather than the science/technology itself."

    The scientists who are primarily involved in climate research come from a broad international background. There is no reason to suspect that they would all pander to the wishes of UK energy policy makers.

    Probably most of the foremost researchers are from the US, which has huge fossil fuel reserves. These scientists are certainly not driving the US's economic policies; often they are at loggerheads with those who do.

    I'd prefer to see the scientists stick to the science, rather than take a role in directing policy. But the fact is that they are often summoned to appear at government committees, etc where they are asked to express their scientific views. It so happens their views very often lend support to those pushing for renewable technologies, etc. This is what politicises the debate, not the scientific views themselves.


  • Comment number 63.

    #61. - newdwr54 wrote:
    "I'm not sure that any scientific paper has predicted progressive warming in winter for the UK. Some scientist may have made unguarded remarks to this effect, but that's not the same thing as a scientific prediction. My understanding of the IPCC synopsis is that the warming trend is likely be gradual over time. Natural variations will always play a role in modifying day to day temperatures, but the long term trend should be upward."
    On the whole, the general public don't read scientific papers or the IPCC reports. They get their information form t.v. and the newspapers, which in turn, are based on scientific papers and reports. If the reports in the media were wrong, I don't recall ever seeing scientist rushing forward to correct them.
    I find it interesting that "warmists" are now starting to deny they ever said the things they did say. Is this part of a 1984 style re-writing of history?


  • Comment number 64.

    newdwr54@40 says . .
    " . . .The evidence in the climate record is consistent with that theory. There has been low solar output of late, so 'all other things' have not been equal. All the IPCC reports, and all the climate scientists as far as I am aware, accept that there are other 'forcings' that can influence climate - ocean cycles and insolation among them."

    Yet you consider the solar climb throughout the 20 Century to be 'equal'?
    So often I have read that solar is considered a minor forcing when compared to CO2 and that the divergence post 1960 proves this. However, here we are, after 50 years or so of historically high solar output (at maxima) and suddenly, a slightly longer than average solar minimum is considered influential.

  • Comment number 65.

    63. QuaesoVeritas:

    I'm not sure if anyone's denying having said certain things, but you'd accept that there has to be a distinction between what a person says in an off the cuff interview and what they put into a scientific paper. It's easy to make a mistake (or be misinterpreted) in a conversation, but academic papers are 'forever', and the scientists will make sure their findings are accurately presented there.

    I'm not suggesting that the conclusions of the scientific papers are guaranteed to be correct, just that these are the places we should look if we want to get a grasp on what is 'actually' being claimed.

  • Comment number 66.

    64. lateintheday:

    All are agreed that solar output has been high in historical terms. The IPCC accepted that solar input was a major driver of warming up to the middle of the 20th century.

    However the slow declining trend in solar output since the mid 1950s as measured by sunspot activity, and later confirmed by TSI measurements from satellites, is simply not matched by a decline in temperatures. These have continued to increase, on average, throughout that period, especially since 1979: http://www.woodfortrees.org/plot/pmod/mean:12/normalise/plot/pmod/trend/normalise/plot/uah/mean:12/plot/uah/trend

    So a question that could be asked in return is: 'if solar input is the main driver of climate, then why have global temperatures risen sharply on average during a period when solar input fell sharply on average?'

  • Comment number 67.

    newdwr54 says
    "The scientists who are primarily involved in climate research come from a broad international background. There is no reason to suspect that they would all pander to the wishes of UK energy policy makers."

    This is not what I intended to suggest. I don't believe for a moment that the UK is that influential. I suggest you take another look at Kyoto to see who signed up and who didn't and then try to figure for yourself out what their motives were.

    If, as you suggest, the USA are leaders in the research field, what possible motives would they have for not signing up fully? Looking at the lack of progress since then shows that those who have substantial natural energy reserves are less than willing to give them up.

    My suggestion is that the fading European powers in particular, require a new playing field in order to maintain their economies. Support for renewables is 'convenient' if it mandates that developing nations must also adhere to the same rules or risk loss of trade.

    I'm not suggesting that this is all 'one big conspiracy'. I'm simply saying that governments of all colours cherry pick their supporting science.

    As for the USA. My understanding is that while they sit on huge reserves - getting the stuff out of the ground will soon (if not already) be more expensive than buying it from other countries.

  • Comment number 68.

    @ new#64

    "The point about 'sceptical' commentators, especially bloggers, is that very often they have an overtly political or economic motive for their scepticism. Often this is accompanied by a lack of any actual scientific training in this specific area"

    This is ad hom and nothing more. To suggest all skeptics are dellingpoles is to equate all warmists to Gore.

    Further the political and economical motives you try to ascribe say more about yourself than those you attempt to label.

    re your #66

    There are more than two factors associated with the sun that affect climate, there are also many other climatic factors (and the position of the individual internal forcings in their own cycles at the stage of solar reduction) that have different and completely un-understood effect on the lag from any fall in energy input.

    Things are not as clear as 'you' make out and our knowledge on the climate is still seriously lacking.- see the recent 'cape' current descoveries for yet further evidence of this.

  • Comment number 69.

    "So a question that could be asked in return is: 'if solar input is the main driver of climate, then why have global temperatures risen sharply on average during a period when solar input fell sharply on average?"

    Excellent question! Wish I knew.

    As QV points out above, the general public (me, in this case) cannot evaluate the relative merits of any scientific paper. So we are left with the dreaded 'delingpoles' of the world to put things in joe public perspective. As a counterbalance, I read blogs like this in order to get a better handle on the science.

    Back to the question. It seems perfectly plausible that increases in Solar activity are not well handled by the earth over the course of one cycle. That this delay in reaching equilibrium accounts for the gradual rise in OHC which is subsequently an additional forcing during the following solar cycle - just like compound interest. If this is the case, then the big question is how long will it take before the extra energy in the oceans is finally released - one low solar cycle, two, five?

    That's without accounting for ENSO and longer term ocean cycles which may in themselves, be in part, a function of previous solar cycles. I believe Landsheidt tried to come up with a connection back in 2001. (think it failed)

  • Comment number 70.

    So are we going to get a similar summer to 2007 (I'll order a canoe now!)

    I've not seen the "cloud of doom" yet (strange looking thing which came in with the first rains of 2007, looked a bit like a vapour trail but grey and low stretching all across the sky) so heres hoping for an ok summer

    I'd like to book some thunder storms in for next week if possible though :)

  • Comment number 71.

    67. lateintheday:

    The divide between the scientific consensus among US climate scientists and the views of US policy makers has become wider of late. Not only did the US not ratify Kyoto, its Senate is moving to strip powers away from its science-driven EPA.

    Is there not a certain inconsistency in the US's attitude to risk? Military expenditure is based on 'worst case scenario' (possibility of WMDs in Iraq); yet firm scientific projections on climate change are ignored because they are 'not proved'.

    68. LabMunkey:

    I did not mean to give the impression that all dissenting voices on AGW are scientific illiterates. I accept that there are some atmosphere and climate specialists who disagree with the consensus on AGW. You would accept however that, while they may still be proven to be correct, they are in a small minority.

    I do not have any strong political views on how to handle the potential threat posed AGW. I try to concentrate on the available information and where this leads me. I accept that this is constantly changing and there is much uncertainty.

    My point re these particular commentators is that their firmly stated views have been formed in the absence of their having any real understanding of the scientific arguments. Delingpole even admits this openly ('interpreter of interpretations').

    No doubt there are commentators on the 'environmentalist' side who are equally guilty of this, only taking the opposite view.

  • Comment number 72.

    69. lateintheday:

    There is a time lag between energy input to the atmosphere, whether from the sun or from an enhanced greenhouse effect. This is mostly due to the thermal inertia of the oceans.

    As you may know, AGW theory also has its 'missing heat' issue. If the climate sensitivity of CO2 is around 3.0 C per doubling of concentrations, which is where most agreement lies, then we should already have seen a warming of about 1.4 C. Instead it's about 0.8 C. The rest is 'in the pipe line'.

    This means that even if greenhouse gases don't rise above their present level, temperatures and sea levels should continue rising for another century or more. So the theory goes.

  • Comment number 73.

    #71 - newdwr54 wrote:
    "yet firm scientific projections on climate change are ignored because they are 'not proved'."
    By what definition do you describe them as "firm scientific projections"?
    How can they be "firm" and at the same time "not proved".



  • Comment number 74.

    73. QuaesoVeritas:

    The terminology used in IPCC AR4 is "very likely", defined as 90-99% probability, that most of the observed warming since the mid 20th century is due to the increase in man made greenhouse gas concentrations.

    Future coastal erosion due to sea level rise, coral bleaching, coastal wetland depletion and low land coastal flooding is stated with "very high confidence", defined as at least a 9/10 likelihood. Loss of biodiversity in wetlands and reef systems also gets this level of likelihood, as do "increases in the severity and frequency of storms" in Australia, especially Queensland [AR4 2007, WGII, SPM, pg. 13].

    Contrast this with the patchy 'intelligence' surrounding the Iraq WMD debacle. In 2003, UN weapons inspectors reported that they had found no evidence that Iraq had stockpiles of WMDs. What happened? Iraq was invaded 'just in case'. As it turned out, the UN inspectors were right.

    In 2007 the UN warned that AGW was very likely to be real, and stated with very high confidence that there would be future negative impacts on human societies and ecosystems. Some of these may already be coming to pass. What happened? Nothing, 'not enough proof'.

    That's inconsistent.

  • Comment number 75.

    lateintheday @ #69

    I haven't been posting here recently as I don't have time just now to respond in detail to individual points. However, I am still reading much of what is being said.

    I think newdwr54 is doing an admirable job of dealing with most points being raised. However, I feel I have to pick you up on this comment:

    "As QV points out above, the general public (me, in this case) cannot evaluate the relative merits of any scientific paper. So we are left with the dreaded 'delingpoles' of the world to put things in joe public perspective. As a counterbalance, I read blogs like this in order to get a better handle on the science."

    I seem to remember you saying that you are involved in policy. If that is the case, I would be very concerned if you are using blogs such as this to "get a better handle on the science".

    If you are wanting to know what the REAL debate amongst scientists is about, you need to follow Realclimate and Roy Spencer's blog, which are written by leading researchers in the field.

    Also, as I've pointed out many times, it isn't the merits of any particular paper that is most important. Rather it is placing the findings of each paper in the context of ALL the scientific literature. The latter is where most of the blogs fall woefully short.

    Paul

  • Comment number 76.

    PB - welcome back to the merry-go-round

    You have me confused with someone else I'm afraid - I'm not involved in policy. Nor am I in anyway connected with the contentious issues of AGW or energy. I'm as joe public as they come. I guess you could say in that respect, I'm your worst nightmare - a bit on the 'thicky" side with opinions formed through reading many, many blogs over the last 18 months. I have no intellectual right to hold an opinion on these matters but nevertheless, I have one based on my judgement of the quality of evidence and responses to such. I gather that a few visitors here - yourself included, have the benefit of being able to evaluate the quality of the science - respect to all.

    For the record, I read both pro and anti AGW blogs including those you mention.

  • Comment number 77.

    @ New#71

    Fair enough mate and i agree re:dellingpole.

    On your point on the 'consensus' i accept that the majority of climate scientists hold the consensus view, you must accept however that this adds nothing to the weight of their argument, just as if only 10% held it to be true, the argument (scientifically speaking) has the same value.

    Further, many scientists outside the field vehemently oppose the theory and in science it is often these 'outside' elements that change the consensus/theories/held beliefs (far too many examples of this to list).

    your # 72,
    All assumes that the theory is right.- This is an issue i have, gaps in the theory are plugged by assuming the theory itself is correct- its self-re-inforcing.

    So rather than saying this particular aspect supports the null hypothesis 'you' (collective) say that the theory will be right, eventually. Doesn't work like that mate.

    your 74-

    The ippc probability statements have already been eviscerated by Dr curry and other eminent scientists (both climate and not). Your first quote in fact is completely unsupported in the IPCC literature given the inability to show the natural and quantify that natural forcings, it is Actually IMPOSSIBLE to ascribe that level of significance.

    Finally linking iraq to cAGW works on more levels than you think, you could easily argue that both were politically motivated and both were for other reasons than advertised. But to suggest that we went into iraq so we should combat cAGW is, weak.

    @Paul #75

    "If you are wanting to know what the REAL debate amongst scientists is about, you need to follow Realclimate and Roy Spencer's blog, which are written by leading researchers in the field"

    Lol. Paul is 100% right. If you want to see typical climate science in action, follow these people closely.

  • Comment number 78.

    #74 - newdwr54 wrote:
    "The terminology used in IPCC AR4 is "very likely", defined as 90-99% probability, that most of the observed warming since the mid 20th century is due to the increase in man made greenhouse gas concentrations."
    Why, in that case, is the current temperature below 88% of temperature model projections in scenario A2 and even below the "commitment scenario", which assumes ZERO GROWTH in greenhouse gasses since 2000? I would argue that a statistical probability isn't the same as proof. As the old saying goes, "the proof of the pudding is in the eating".

    "Future coastal erosion due to sea level rise, coral bleaching, coastal wetland depletion and low land coastal flooding is stated with "very high confidence", defined as at least a 9/10 likelihood. Loss of biodiversity in wetlands and reef systems also gets this level of likelihood, as do "increases in the severity and frequency of storms" in Australia, especially Queensland [AR4 2007, WGII, SPM, pg. 13]."
    Most of the above are natural processes, which were going on well before, and are also affected by other human activity not connected with, "climate change". However, even if they were entirely caused by "global warming", they are dependant upon the warming predicted in the models taking place, for which, as I have pointed out, there is so far absolutely no evidence.
    I agree with you on Iraq. In that case, the standard of evidence was very low, along the lines of, "here is a photograph of a building, which is a weapons factory, which proves Iraq has WMD". If I could see through it, I don't know why the U.N. couldn't. I can only assume that this is something to do with the simplicity of dealing with the situation. If there was a single "evil scientist" somewhere, causing "climate change", the U.S. would probably bomb him. Dealing with the threat of "climate change", especially when it is entirely based on future projections, and you may be causing it yourself, is an entirely different matter.

  • Comment number 79.

    78. QuaesoVeritas wrote:

    "Why, in that case, is the current temperature below 88% of temperature model projections in scenario A2 and even below the "commitment scenario", which assumes ZERO GROWTH in greenhouse gasses since 2000?"

    As you may be aware all the scenarios are based on multi-model global averages, relative to the 1980-1999 average. They run from 2000. The 'solid line' is the mean of all the model projections, so is not stated with the sort of confidence that I was referring to previously. As you can see all the models have a considerable 'uncertainty' overlap in the early stages: http://www.ipcc.ch/publications_and_data/ar4/wg1/en/figure-spm-5.html

    AR2 is running at the lower end of the model estimates, but the trend 'is' upwards and it is within the modelled range. AR4 does state:

    "For the next two decades, a warming of about 0.2°C per decade is projected for a range of SRES emission scenarios. Even if the concentrations of all greenhouse gases and aerosols had been kept constant at year 2000 levels, a further warming of about 0.1°C per decade would be expected."

    As you know, the current decadal rate is 0.15 oC on average. I'm not making excuses for the models, they may lack accuracy in the long run. I was just drawing attention to the attitude of the US in particular to risk mitigation.

  • Comment number 80.

    Re my above, just for accuracy, the +0.15 C per decade rate runs from 1979. The trend based on 2000 anomaly (using HadCRUT3) is 0.6 C per decade. This is much lower than the 1979 one, before anyone points it out! However, with normal rounding, it is still "about 0.1°C per decade", albeit at the lower end of the estimates.

  • Comment number 81.

    Further amendment - that should be +0.06 (not +0.6) rounded to +0.1. Sorry :d

  • Comment number 82.

    77. LabMunkey:

    It's true that the dissenting scientists may be right. But which? It's not as if they are all supporting the same alternative model. Often the disagreements they have with one another amount to greater differences than they have with the consensus view.

    Re the radiative forcing of CO2; I did, as you say, base my argument on the premise that its climate sensitivity is roughly 3 oC per doubling. This may be wrong, but again it is the 'consensus' view, and the observed rate of warming is not inconsistent with that estimate.

    Re the probability statements, the AIC review recommended that these should be used "only when there is sufficient evidence". These probability statements tend to be made in the associated SPMs, rather than in the main body of the reports. They amount to 'expert opinion' and are therefore not strictly quantifiable. However they still represent the views of the expert panels.

    Re Iraq , I didn't suggest that we went into Iraq so we could combat climate change. I was just highlighting our willingness to intervene in Iraq despite the sparse and contradictory evidence there was on WMDs. Contrast that with the relative lack of US intervention in particular on climate change.

    All the national scientific academies have backed the IPCC findings on AGW to some extent at least, so whatever way you look at it there is much more 'evidence' for AGW than there was for WMDs in Iraq. Yet elements in the US congress and senate are actually trying to repeal what limited mitigation measures that country has so far put in place. This demonstrates and inconsistent attitude to risk, in my view, whether or not AGW turns out to be wrong.

  • Comment number 83.

    #79 - newdwr54 wrote:
    "As you may be aware all the scenarios are based on multi-model global averages, relative to the 1980-1999 average. They run from 2000. The 'solid line' is the mean of all the model projections, so is not stated with the sort of confidence that I was referring to previously."
    I wasn't referring to the mean, although the actual temp. is oviously below that, but to the individual models used for scenario A2. The fact remains that the current temperature is below 15 of the 17 models and it is only a matter of time before it is lower than all 17, based on a 3 year average HadCRUT3 anomaly.
    "AR2 is running at the lower end of the model estimates, but the trend 'is' upwards and it is within the modelled range."
    Do you mean that the actual temperature is at the lower end of the estimates. If so, I think that is an under statement.

    "As you know, the current decadal rate is 0.15 oC on average."
    I'm not sure if the decadal rate is relevant as far as the model projections are concerned, because I believe (although it isn't mentioned on the graph you linked to), that they are based on 3 year averages. However even using your final (rounded up) figure, the decadal trend is no more than was predicted as a result of zero growth in greenhouse gasses.
    What I am interested to know is whether the IPCC will stick with these projections in AR5, or will it be forced to publish revised projections based on reality. Presumably the models will be re-run, but will they be "adjusted" to bring them back in line with the AR4 projections?

  • Comment number 84.

    @ 82.
    I agree not all sceptics support the same 'model' (some are, quite frankly, crackpots) but they broadly follow the same line:
    -the evidence for cAGW is overstated
    -the effect of AGW itself is overstated
    -the inability to quantifiy (even roughly) the natural forcings negates any attribution of an anthropogenic signal.
    -there are vast gaps in knowledge on significant factors in our climate (eg clouds).

    People can support any of these without them being mutually exclusive. A consistent 'voice' as it were is not required, the fact that there is large amounts of dissent at all is significant.

    - The radiative forcing line is, again, using an assumption to back-up an assumption. Further, your conclusion that the 3 'c doubling is 'consistent' completely relies on another assumption- that discarding all natural forcings was correct.

    -Re- Iraq, i think you misunderstood me. I was trying to say that drawing parralels between the two is exceptionally foolish- especially given the side of the debate you happen to reside on just now.

    -then you close on an appeal to authority- something i've already pointed out as irrelevant.

  • Comment number 85.

    " . . .this demonstrates and inconsistent attitude to risk, in my view, whether or not AGW turns out to be wrong."

    This would be a fair point if you actually believed that WMD were the primary motive for invading Iraq which surely you don't. WMD was the best excuse at the time for something that was necessary (in their eyes) but otherwise illegal.

    As I pointed out @67, governments of all colours tend choose the science or evidence that supports what they want to do. While some scientists may be 'on message', chances are that most are just doing their best and subsequently find their work twisted or spun by the politics of the day.

  • Comment number 86.

    83. QuaesoVeritas:

    Like you I'm not completely sure what way the IPCC run the trends, i.e. over what time lines, etc. At the moment A2 scenario is still 'just' within its projected bands (which still overlap with those of several other scenarios at this early stage) and the trend is still upward from 2000.

    If it transpires that temperatures dip out of that band in the next 2-3 years, then it is the role of the IPCC, which is a peer review body, to ensure that the reporting scientists revise their projections for A2 downward in the next report to reflect observations. In that case they should admit that the previous models' results were probably too high on average. But I think it's still slightly early days to call that one just yet.

    84. LabMunkey:

    Of your list of common sceptic objections I'd agree with three. The fourth: "-the inability to quantifiy (even roughly) the natural forcings negates any attribution of an anthropogenic signal" I would strongly disagree with.

    Certainly as far as quantifying mid-long term forcings there are difficulties, but total solar input since 1979 is known with a high degree of precision, as is volcanic output and atmospheric aerosol content, etc. Ocean circulation models are less certain, admittedly.

    You imply that the 3 oC climate sensitivity per doubling of CO2 is some sort of wild guess. It is the result of numerous peer reviewed studies into paleoclimate data, more recent experimental observations, and papers produced from widely tested climate models. You might not agree with the 3 oC CS conclusion of these papers, but the figure is far from being a random 'assumption'.

    I'll visit the Iraq theme once more: the comparison was simply intended to demonstrate government 'inconsistency'; inconsistency being a fallacy of logic. US and UK Governments were prepared to act on 'weak' evidence in the face of possible danger in Iraq. Yet the US now refuses to act decisively on 'strong' evidence on AGW.

    I mentioned the stance of National Academy not as an appeal to authority, but to underscore that the US government in particular remains inconsistent in its stance on public risk management, even in the face of advice from its most respected scientific institution. (Maybe if the CIA was giving the advice the Senate might be more predisposed to giving AGW mitigation more funding?)

    85. lateintheday:

    That's all probably true.

  • Comment number 87.

    #86. - newdwr54 wrote:
    If it transpires that temperatures dip out of that band in the next 2-3 years, then it is the role of the IPCC, which is a peer review body, to ensure that the reporting scientists revise their projections for A2 downward in the next report to reflect observations. In that case they should admit that the previous models' results were probably too high on average. But I think it's still slightly early days to call that one just yet."
    You use the term "dip", to imply a temporary drop below the band, which will soon be reversed. I don't think it will be like that. By the time the AR5 is finalised (Sept. 2014 ?), I believe that actual temperatures will have been below all of the A2 scenario projections for over 2 years.
    Given the ramifications of admitting that all of the models in this scenario were too high, (I believe it will completely destroy the credibility of the IPCC climate projections), I expect that the IPCC will do everything in its power to obscure that fact, so it will be interesting to see how they do that.


  • Comment number 88.

    lateintheday @ #76

    "You have me confused with someone else I'm afraid........."

    Maybe just another sign of the advancing years!!

    Paul

  • Comment number 89.

    87. QuaesoVeritas:

    You old cynic you!

    I'm of the view that temperatures will either remain within the A2 projection or else dip out very briefly. I expect to see the start of a more rapid incline in the trend after the La Nina effects pass - so second half of 2011.

    It's a stand off...

  • Comment number 90.

    It is 1105Z here in Lincolnshire and it has now been gently RAINING for about 30 mins. So your forecast is early Paul. Never mind, better early than never! It is cooler than forecast as well but this is subjective since I do not have an accurate Max/Min Thermometer.

    Prof Nils-Axel Morner of Sweden has forecast a mini ice age by 2040 due to another protracted solar minimum. Prof Morner is a climatologist and expert on sea levels. He has measured sea level rise as about 3mm/year +/- 1mm or so. This measurement is very difficult to calculate exactly but nothing like the figures from the UK Environment Agency or Hadley or UAE none of whom are experts on sea level rise or fall. Latest figures, early 2011, suggest sea level rise has leveled off due to ocean cooling.

  • Comment number 91.

    #66 - newdwr54 wrote:
    "All are agreed that solar output has been high in historical terms. The IPCC accepted that solar input was a major driver of warming up to the middle of the 20th century.
    However the slow declining trend in solar output since the mid 1950s as measured by sunspot activity, and later confirmed by TSI measurements from satellites, is simply not matched by a decline in temperatures. These have continued to increase, on average, throughout that period, especially since 1979: http://www.woodfortrees.org/plot/pmod/mean:12/normalise/plot/pmod/trend/normalise/plot/uah/mean:12/plot/uah/trend
    So a question that could be asked in return is: 'if solar input is the main driver of climate, then why have global temperatures risen sharply on average during a period when solar input fell sharply on average?'"
    Sorry to quote your entire post, but I think it makes it easier to refer to it.
    Personally, I have never been convinced of the influence of solar activity on global temperatures.
    Your own graph shows that recently, temperatures have risen while TSI has decreased. I have been looking at it on a longer-term basis, using sunspot numbers compared to HadCRUT3, and the situation does not look clear.
    The 10 year MA of SSN appears to show a general decline between 1880 and 1905, a gentle rise between 1905 and 1936 and a steeper rise between 1936 and 1964. On the other hand, the 10 year HadCRUT3 MA generally fell between 1889 and 1913, and rose quite steeply between 1913 and 1946. That all looks quite neat as far as a relationship is concerned, but unfortunately, the HadCRUT3 MA then fell quite rapidly between 1946 and 1956, while the SSN MA continued to rise.
    The HadCRUT3 MA continued to rise again after 1956 and even faster from about 1976, while the SSN MA generally fell between 1964 and 2007. (This is all clearer in a graph!).
    However, when you look at an even longer timescale, i.e. 50 year moving averages, the situation is a little clearer. In this case, the SSN MA generally fell between 1900 and 1936, while the HadCRUT3 MA generally fell, and rose between 1936 and 1995, while the HadCRUT3 also rose. Unfortunately, while the SSN MA started to decline in about 1995, the HadCRUT3 MA continued to rise at an even faster rate.
    Obviously, there may be a time-lag involved but the rise in the HadCRUT3 MA from 1936 appeared to respond almost immediately to the rise in SSN. However, it is possible that there is a longer time-lag following a fall in sunspot numbers than following an

  • Comment number 92.

    John Marshall @90
    You're probably aware of the recent 'adjustment' of +0.3mm to sea level data. Some people question the motive, others question whether the adjustment has any effect on the trend.

    This post at WUWT seems like a reasonable summary of two sides of the coin. John, motives aside, can you (or anybody else) clear up whether there is an effect on trend.


    OldOne says:
    May 6, 2011 at 6:38 am
    Buzz Belleville says:
    May 6, 2011 at 5:32 am
    You do understand, fellow posters, that the Colorado page is not just adding 0.3 mm to the current year to show a greater rise in sea levels. It’s adding o.3 mm to all plotted points. It has no effect on the rate of rise.

    Buzz, per their website, the GIA adjustment was “-0.3 mm/yr. That’s per year.
    The most recent ‘pre-adjusted’ data point for 2010.7415 was 28.119 mm.
    This ‘post-adjusted’ data point for 2010.7415 is now 36.996 mm.

    So you’re correct that they didn’t just add 0.3 mm to the current year, they added 8.877 mm to the most recent common data point
    It does affect the rate of rise!

  • Comment number 93.

    QV @91 - your post was cut short unfortunately.
    The correlation in SSN and temps did seem to hold up well for a few decades. But as pointed out earlier, the drop in temps did not fully reflect the decline to solar cycle min, even during the 1900 - 1950 period.

    This is at least, a possible indication that the general rise in solar activity throughout this period was too fast for the climate system to cope with. Therefore, each following cycle already had additional heat left to dissipate from the previous cycles. See @69.
    I know it isn't 'science' but it does seem reasonable to a layman.

    In this 'model', solar effects are immediate (cycle), delayed (stored in ocean) and cumulative (compound interest). With all the other cycles and forcings thrown in, it's a messy picture to be sure.

  • Comment number 94.

    93. At 15:47pm 7th May 2011, lateintheday wrote:
    "QV @91 - your post was cut short unfortunately."
    Yes, there did seem to be a glitch when I posted it but I hadn't noticed it had been cut short. Possibly too large.
    Fortunately, (or unfortunately), I copied the post and saved it, so here is the rest:

    Obviously, there may be a time-lag involved but the rise in the HadCRUT3 MA from 1936 appeared to respond almost immediately to the rise in SSN. However, it is possible that there is a longer time-lag following a fall in sunspot numbers than following an increase. I haven't got enough data going back to the start of the previous fall in SSN, so I can't verify that.
    BTW, the moving averages I am referring to are at the end of the period in question, i.e. the 50 year MA for 1995 covers the period 1946-1995. I know that it would be more correct to refer to that as the average for the mid-point of about 1970, but I get confused when I do that. Also, it is often difficult to establish exactely when a trend changes, due to the solar cycle, which shows up nicely in the 50 year MA.

    I also forgot to mention that according to Wikipedia, variations in solar irradiance were too small to detect with the technology available prior to the satellite era, so I wonder if that casts doubt on how much influence it could have on global temperatures.




 

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