Has Global Warming Stalled? (Now Includes January Data)

WoodForTrees.org – Paul Clark – Click the pic to view at source

Guest Post By Werner Brozek, Edited By Just The Facts

In order to answer the question in the title, we need to know what time period is a reasonable period to take into consideration. As well, we need to know exactly what we mean by “stalled”. For example, do we mean that the slope of the temperature-time graph must be 0 in order to be able to claim that global warming has stalled? Or do we mean that there has to be a lack of “significant” warming over a given period? With regards to what a suitable time period is, NOAA says the following:

”The simulations rule out (at the 95% level) zero trends for intervals of 15 yr or more, suggesting that an observed absence of warming of this duration is needed to create a discrepancy with the expected present-day warming rate.” To verify this for yourself, see page 23 here

Below, we will present you with just the facts and then you can decide whether or not global warming has stalled in a statistically significant manner.

The information will be presented in three sections and an appendix. Section 1 will show for how long there has been no warming on several data sets. Section 2 will show for how long there has been no significant warming on several data sets. Section 3 will show how January 2013 compares with 2012 and the warmest years and months on record so far. The Appendix will illustrate Sections 1 and 2 in a different way. Graphs and a table will be used to illustrate the data.

Section 1

This analysis uses the latest month for which data is available on WoodForTrees.com (WFT). However WFT has not been updated for GISS, Hadcrut3 and WTI past November so I had to use the SkS site for GISS and Hadcrut3. All of the data on WFT is also available at the specific sources as outlined below. We start with the present date and go to the furthest month in the past where the slope is a least slightly negative. So if the slope from September is 4 x 10^-4 but it is – 4 x 10^-4 from October, we give the time from October so no one can accuse us of being less than honest if we say the slope is flat from a certain month.

On all data sets below, the different times for a slope that is at least very slightly negative ranges from 4 years and 7 months to 16 years and 1 month.

1. For GISS, the slope is flat since May 2001 or 11 years, 9 months. (goes to January)
2. For Hadcrut3, the slope is flat since March 1997 or 15 years, 11 months. (goes to January)
3. For a combination of GISS, Hadcrut3, UAH and RSS, the slope is flat since December 2000 or an even 12 years. (goes to November)
4. For Hadcrut4, the slope is flat since November 2000 or 12 years, 3 months. (goes to January)
5. For Hadsst2, the slope is flat since March 1997 or 15 years, 11 months. (goes to January)
6. For UAH, the slope is flat since July 2008 or 4 years, 7 months. (goes to January)
7. For RSS, the slope is flat since January 1997 or 16 years and 1 month. (goes to January) RSS is 193/204 or 94.6% of the way to Ben Santer’s 17 years.

The next graph shows just the lines to illustrate the above. Think of it as a sideways bar graph where the lengths of the lines indicate the relative times where the slope is 0. In addition, the sloped wiggly line shows how CO2 has increased over this period.

WoodForTrees.org – Paul Clark – Click the pic to view at source

When two things are plotted as I have done, the left only shows a temperature anomaly. It goes from 0.1 to 0.6 C. A change of 0.5 C over 16 years is about 3.0 C over 100 years. And 3.0 C is about the average of what the IPCC says may be the temperature increase by 2100.

So for this to be the case, the slope for all of the data sets would have to be as steep as the CO2 slope. Hopefully the graphs show that this is totally untenable.

The next graph shows the above, but this time, the actual plotted points are shown along with the slope lines and the CO2 is omitted.

WoodForTrees.org – Paul Clark – Click the pic to view at source

Section 2

For this analysis, data was retrieved from SkepticalScience.com. This analysis indicates for how long there has not been significant warming according to their criteria. The numbers below start from January of the year indicated. Data have now been updated either to the end of December 2012 or January 2013. In every case, note that the magnitude of the second number is larger than the first number so a slope of 0 cannot be ruled out. (To the best of my knowledge, SkS uses the same criteria that Phil Jones uses to determine significance.)

For RSS the warming is not significant for over 23 years.
For RSS: +0.127 +/-0.134 C/decade at the two sigma level from 1990
For UAH the warming is not significant for over 19 years.
For UAH: 0.146 +/- 0.170 C/decade at the two sigma level from 1994
For Hadcrut3 the warming is not significant for over 19 years.
For Hadcrut3: 0.095 +/- 0.115 C/decade at the two sigma level from 1994
For Hadcrut4 the warming is not significant for over 18 years.
For Hadcrut4: 0.095 +/- 0.110 C/decade at the two sigma level from 1995
For GISS the warming is not significant for over 17 years.
For GISS: 0.111 +/- 0.122 C/decade at the two sigma level from 1996

If you want to know the times to the nearest month that the warming is not significant for each set, they are as follows: RSS since September 1989; UAH since June 1993; Hadcrut3 since August 1993; Hadcrut4 since July 1994; GISS since August 1995 and NOAA since June 1994.

Section 3

This section shows data about 2013 and other information in the form of a table. Each table shows the six data sources along the top, namely UAH, RSS, Hadcrut4, Hadcrut3, Hadsst2, and GISS. Down the column, are the following:

1. 2012 rank: This is the final ranking for 2012 on each data set.
2. 2012 anomaly: Here I give the average anomaly for 2012.
3. warmest year: This indicates the warmest year on record so far for that particular data set. Note that two of the data sets have 2010 as the warmest year and four have 1998 as the warmest year.
4. anomaly of above: This is the average of the monthly anomalies of the warmest year just above.
5. warmest month: This is the month where that particular data set showed the highest anomaly. The months are identified by the first two letters of the month and the last two numbers of the year.
6. anomaly of above: This is the anomaly of the month just above.
7. year/month no warm: This is the longest period of time where the slope is not positive. So 15/11 means that for 15 years and 11 months the slope is 0 or slightly negative.
8. This is the January, 2013, anomaly for that particular data set.
20. This is the average anomaly of all months to date taken by adding all numbers and dividing by the number of months. (Of course, for this time, it would simply be the January anomaly.)
21. This is the rank that each particular data set would have if the anomaly above were to remain that way for the rest of the year. Of course it won’t, but think of it as an update 5 minutes into a game. Expect wild swings from month to month at the start of the year. As well, expect huge variations between data sets at the start. For UAH, the 0.506 was ranked first. That is because 0.506 is above the highest yearly average of 0.419 in 1998. It is not the hottest month ever. That happens to be April of 1998 when the anomaly was 0.66.

Source UAH RSS Had4 Had3 HADSST2 GISS
1. 2012 Rank
9th 11th 10th 10th 8th 9th
2. 2012 Anomaly 0.161 0.192 0.433 0.406 0.342 0.56
3. Warmest Year 1998 1998 2010 1998 1998 2010
4. Anomaly Of Above 0.419 0.55 0.540 0.548 0.451 0.66
5. warmest month Ap98 Ap98 Ja07 Fe98 Au98 Ja07
6. Anomaly Of Above 0.66 0.857 0.818 0.756 0.555 0.93
7. Years / Months With No Warming 4/7 16/1 12/3 15/11 15/11 11/9
8. Jan. 2013 Anomaly 0.506 0.442 0.433 0.388 0.283 0.61
20. 2013 Average So Far 0.506 0.442 0.433 0.388 0.283 0.61
21. 2013 Rank So Far 1st 3rd 10th 12th 12th 4th

If you wish to verify all 2012 rankings, go to the following:
For UAH, see here, for RSS see here and for Hadcrut4, see here. Note the number opposite the 2012 at the bottom. Then going up to 1998, you will find that there are 9 numbers above this number. That confirms that 2012 is in 10th place.

For Hadcrut3, see here. Here you have to do something similar to Hadcrut4, but look at the numbers at the far right. One has to go back to the 1940s to find the previous time that a Hadcrut3 record was not beaten in 10 years or less.

For Hadsst2, see here. View as for Hadcrut3. It came in 8th place with an average anomaly of 0.342, narrowly beating 2006 by 2/1000 of a degree as that came in at 0.340. In my ranking, I did not consider error bars, however 2006 and 2012 would statistically be a tie for all intents and purposes.

For GISS, see here. Check the J-D (January to December) average and then check to see how often that number is exceeded back to 1998.

To see all points since January 2012 in the form of a graph, see the WFT graph below:

WoodForTrees.org – Paul Clark – Click the pic to view at source

Relative to December, the January anomalies have changed as follows: UAH up 0.30, RSS up 0.34, Hadcrut4 up 0.17, Hadcrut3 up 0.13, Hadsst2 down 0.06, and GISS up 0.17.

Dr. Spencer explains why the satellite anomalies are up but the sea surface anomaly is down here.

Appendix

In this part, we are summarizing data for each set separately.

RSS

The slope is flat since January 1997 or 16 years and 1 month. (goes to January) RSS is 193/204 or 94.6% of the way to Ben Santer’s 17 years.
For RSS the warming is not significant for over 23 years.
For RSS: +0.127 +/-0.134 C/decade at the two sigma level from 1990.
The RSS average anomaly so far for 2013 is 0.442. This would rank 3rd if it stayed this way. 1998 was the warmest at 0.55. The highest ever monthly anomaly was in April of 1998 when it reached 0.857. The anomaly in 2012 was 0.192 and it came in 11th.
Following are two graphs via WFT. Both show all plotted points for RSS since 1990. Then two lines are shown on the first graph. The first upward sloping line is the line from where warming is not significant according to the SkS site criteria. The second straight line shows the point from where the slope is flat.
The second graph shows the above, but in addition, there are two extra lines. These show the upper and lower lines using the SkS site criteria. Note that the lower line is almost horizontal but slopes slightly downward. This indicates that there is a slight chance that cooling has occurred since 1990 according to RSS per graph 1 and graph 2.

UAH

The slope is flat since July 2008 or 4 years, 7 months. (goes to January)
For UAH, the warming is not significant for over 19 years.
For UAH: 0.146 +/- 0.170 C/decade at the two sigma level from 1994
The UAH average anomaly so far for 2013 is 0.506. This would rank 1st if it stayed this way. 1998 was the warmest at 0.419. The highest ever monthly anomaly was in April of 1998 when it reached 0.66. The anomaly in 2012 was 0.161 and it came in 9th.
Following are two graphs via WFT. Everything is identical as with RSS except the lines apply to UAH.
Graph 1 and graph 2.

Hadcrut4

The slope is flat since November 2000 or 12 years, 3 months. (goes to January.)
For Hadcrut4, the warming is not significant for over 18 years.
For Hadcrut4: 0.095 +/- 0.110 C/decade at the two sigma level from 1995
The Hadcrut4 average anomaly so far for 2013 is 0.433. This would rank 10th if it stayed this way. 2010 was the warmest at 0.540. The highest ever monthly anomaly was in January of 2007 when it reached 0.818. The anomaly in 2012 was 0.433 and it came in 10th.
Following are two graphs via WFT. Everything is identical as with RSS except the lines apply to Hadcrut4.Graph 1 and graph 2.

Hadcrut3

The slope is flat since March 1997 or 15 years, 11 months (goes to January)
For Hadcrut3, the warming is not significant for over 19 years.
For Hadcrut3: 0.095 +/- 0.115 C/decade at the two sigma level from 1994
The Hadcrut3 average anomaly so far for 2013 is 0.388. This would rank 12th if it stayed this way. 1998 was the warmest at 0.548. The highest ever monthly anomaly was in February of 1998 when it reached 0.756. One has to go back to the 1940s to find the previous time that a Hadcrut3 record was not beaten in 10 years or less. The anomaly in 2012 was 0.406 and it came in 10th.
Following are two graphs via WFT. Everything is identical as with RSS except the lines apply to Hadcrut3. Graph 1 and graph 2.

Hadsst2

The slope is flat since March 1997 or 15 years, 11 months. (goes to January)
The Hadsst2 average anomaly so far for 2013 is 0.283. This would rank 12th if it stayed this way. 1998 was the warmest at 0.451. The highest ever monthly anomaly was in August of 1998 when it reached 0.555. The anomaly in 2012 was 0.342 and it came in 8th.
Sorry! The only graph available for Hadsst2 is the following this.

GISS

The slope is flat since May 2001 or 11 years, 9 months. (goes to January)
For GISS, the warming is not significant for over 17 years.
For GISS: 0.111 +/- 0.122 C/decade at the two sigma level from 1996
The GISS average anomaly so far for 2013 is 0.61. This would rank 4th if it stayed this way and would tie it with 1998. 2010 was the warmest at 0.66. The highest ever monthly anomaly was in January of 2007 when it reached 0.93. The anomaly in 2012 was 0.56 and it came in 9th.
Following are two graphs via WFT. Everything is identical as with RSS except the lines apply to GISS. Graph 1 and graph 2.

Conclusion

Above, various facts have been presented along with sources from where all facts were obtained. Keep in mind that no one is entitled to their facts. It is only in the interpretation of the facts for which legitimate discussions can take place. After looking at the above facts, do you feel that we should spend billions to prevent catastrophic warming? Or do you feel we should take a “wait and see” attitude for a few years to be sure that future warming will be as catastrophic as some claim it will be? Keep in mind that even the MET office felt the need to revise its forecasts. Look at the following and keep in mind that the MET office believes that the 1998 mark will be beaten by 2017. Do you agree?

WoodForTrees.org – Paul Clark – Click the pic to view at source

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83 Responses to Has Global Warming Stalled? (Now Includes January Data)

  1. kim says:

    We are cooling, folks; for how long even kim doesn’t know.
    ===============

  2. crosspatch says:

    Look at the following and keep in mind that the MET office believes that the 1998 mark will be beaten by 2017. Do you agree?

    The problem I have is that this is an adjusted data set and I have no faith in the adjustments. Furthermore, adjustments to many of these data sets seem to be continuously and retroactively so the adjustment of information from the past can change in the future. I have no confidence in the data so whether or not it “breaks” 1998 or not seems rather a silly question. I guess my answer is “yes, if they want it to break 1998, no if they don’t want it to”.

  3. Werner Brozek says:

    JTF, I just have a concern about the size of the graphs. When you click on them, they are good, but when viewed as they are, they are twice as big as they should be and just the left half appears. This applies to 4 out of the 5. Can this be fixed? Thanks!

  4. MattN says:

    I am 100% positive that I remember Gavin stating in a post at Realclimate that if there was no warming for 10 years, that would indicate the models were wrong.

  5. wikeroy says:

    “Look at the following and keep in mind that the MET office believes that the 1998 mark will be beaten by 2017. Do you agree?”

    No one can tell. It might wiggle a bit upwards again like a rising zig-zag, and yet it might not. If it does wiggle upwards again, it is unlikely to be much of an increase compared to 1998…..but noone knows. And noone can know. Bob Tisdale is the one to ask. He seems to be one of the few that has some understanding on how the small variance’s is induced via ENSO. Because they are small, look at the y-axis.

  6. John W. Garrett says:

    Excellent work. This piece needs to be kept close to hand for ready accessibility.

  7. Jim Cripwell says:

    Werner, you write “Look at the following and keep in mind that the MET office believes that the 1998 mark will be beaten by 2017. Do you agree?”

    This is not quite a complete picture of what happened. Using 2004 data Smith et al from the Met. Office, published their decadal forecast in the August 2007 edition of Science. This forecast that, following 2009, half the years would have temperatures in excess of 1998. When this was obviously not happening, the Met. Office quietly altered their forecast; on Christmas Eve 2012. The change was not noted until early in Jan. 2013. We have not yet been given the details of the science behind the new forecast, or the reasons why the Met. Office has abandoned Smith et al.

    So I dont think anyone is in a position to answer the questrion as to whether we agree or not. Surely the Met.Office needs to give us the sort of detail that we were given in Smith et al, BEFORE this question can be answered.

  8. Glenn says:

    I’m not a mathematician but it looks more like a wave than a rise up a hill. The data set does seem too small to make a prediction of any kind though, I don’t know how they’re getting “in-coming heat wave” from that data.

  9. Jimbo says:

    Look at the following and keep in mind that the MET office believes that the 1998 mark will be beaten by 2017. Do you agree?

    Well, based on the record so far I’d say no.

    Looking ahead, The Met Office expects ‘half the years between 2010 and 2015 to be hotter than the hottest year on record’.
    BBC

    And here’s something they prepared earlier.

    “According to the Met Office decadal forecast, at least half of the years after 2009 are expected to be warmer than the 1998 record.”
    Met Office (pdf)

    Further reading:
    Met Office Climate Forecasts: Always Wrong But Never In Doubt

  10. michael hart says:

    Lol. Maybe time for another derivative, such as “The rate of change of climate-change remains the same”?

    The models still have no predictive skill, however frequently the hind-casts are changed to keep up (or down).

  11. FerdinandAkin says:

    Imagine for a moment that the American Clean Energy and Security Act of 2009 had passed and we had a Cap ‘n Trade system for the last three years. Then imagine for a moment how loud the climate alarmistists would proclaiming the effectiveness of their efforts. It would be a case of the rooster crowing and then taking credit for the sunrise.

  12. John Whitman says:

    Keep in mind that no one is entitled to their facts. It is only in the interpretation of the facts for which legitimate discussions can take place.

    - – - – - – - – -

    Werner Brozek,

    I think your statement is too prescriptive to be true.

    Surely a person is entitled to present what they consider facts for others to ‘fact check’.

    Surely people are entitled to ‘fact check’ all things presented as facts . . . . even when the facts are presented by GISS, HadCRU, RSS and UAH.

    That is my only criticism of your very useful post about the temp time series of the past several decades. Thank you for your efforts to bring this to WUWT.

    John

  13. MikeN says:

    Oh no he didn’t! Taking SkepticalScience tools to show no warming is going to make some people very upset. Note that that definitely non-skeptic website likes to edit posts and comments without notice, so look for the tool to change in a substantial way after this post.

  14. Nik Marsall-Blank says:

    As I understand, the adjusted data is because of the time that the temperatures readings were taken. They were in the mornings I believe and now later in the day. But I have some problems with this.

    Once adjusted, the temperatures seem still subject to more adjustments as time goes by. Also the baseline temperature is adjusted.

    And one more worry, if the adjustments are made to adjustments then what happens to .6 + .6. Does this become 1 + 1 = 2 or (.6 + .6) = 1.2 = 1?

    After so many adjustments just thinking about it makes my head hurt.

  15. Alan S. Blue says:

    It would be helpful if both of the separate y-axes were labeled. The CO2 line is obviously not measured in degrees – and putting a second y-axis on the -right- for ppm would make this a fairly common method of plotting two disparate things on one chart.

  16. Caleb says:

    The problem has never been warming. Warming such as the Roman Optimum and the MWP have been kinder to humanity than times such as the LIA. The problem is likely to be cooling, and a time of troubles.

    Should those troubles come, those who like to work behind the scenes will simply say, “Never let a good crisis go to waste,” and will attempt to continue to leech off the ignorant. However those who enjoyed the spotlight will be marked men (and women,) stained by a blot that will not wash away.

  17. David L. Hagen says:

    The important issue is NOT whether global temperatures have been “warming” or “stalled”, since they have been warming since the Little Ice Age with oscillations on top of that trend.
    The critical issue is whether there is MAJOR anthropogenic global warming as advocated by the IPCC, rather than minor anthropogenic global warming or statistically unquantifiable global warming.
    The scientific challenge is to quantitatively distinguish between three major models:
    A) Damaging Anthropogenic Global Warming: > 50% of warming due to humans, OR
    B) Minor Anthropogenic Global Warming: 5% to 50% of warming due to humans, OR
    C) Null Hypothesis: Natural Global Warming: < 5% or unknown due to humans.

    Lack of statistically significant global warming for extended periods at least shows the IPCC’s models are wrong, and probably that there is NOT dangerous anthropogenic global warming. The IPCC sea temperature model trends are now running 3 times too hot since 1998.
    To find out which model is better, the challenge is to statistically quantify the difference between models for both major and minor anthropogenic global warming over the null hypothesis of natural global warming with natural fluctuations since the Little Ice Age.
    Compare models by:
    the Global Warming Prediction Project
    Nicola Scafetta
    and
    Syun-Ichi Akasofu, On the recovery from the Little Ice Age, Natural Science, Vol.2, No.11, 1211-1224 (2010), doi:10.4236/ns.2010.211149 http://www.scirp.org/journal/NS/

    The far greater climate challenge is:
    Can we prevent descent into the next glaciation in some 1500 years?

  18. Leo Morgan says:

    I am very angry about the NOAA quote above. I feel very let down by those who have excerpted it from the report. I had trusted it to be correct, and nearly repeated the quote myself. I had a narrow escape, because, deliberately or otherwise, It misrepresents what the authors were saying.
    The discussion at ‘the blackboard’ led me to read the full context. The quote is talking about 15 years of absence of warming from ENSO- adjusted data sets, not 15 years of absence of warming from raw temperature measurements. The second is what I took it to mean, and how most skeptical users of the quote have presented it as meaning. But that just plain wrong.
    The website drroyspencer.com demonstrates that there clearly has been warming in the ENSO-adjusted data set.
    Rightly, he points out that the actual measurement is significantly below the forecast measurement- but that does not justify us taking the quote out ofvthe context of ENSO adjusted data sets and applying it to raw temperature measurements.
    For shame, people.

  19. John Whitman says:

    Werner Brozek,

    [ . . ] After looking at the above facts, do you feel that we should spend billions to prevent catastrophic warming? Or do you feel we should take a “wait and see” attitude for a few years to be sure that future warming will be as catastrophic as some claim it will be? Keep in mind that even the MET office felt the need to revise its forecasts. Look at the following and keep in mind that the MET office believes that the 1998 mark will be beaten by 2017. Do you agree?

    - – - – - – - – - -

    Werner Brozek,

    Responses to your two questions are:

    To your first question => No waiting for me, it is a waste of my precious life, just live with a reasonable eye on only the plausible potentials and then determine individualistic priorities.

    To your second question => I do not know what the average GST anomaly will be in 2017 and neither does the MET. However, I think in the decadal timescale there will be overall moderate cooling based on my understanding of several physical phenomena.

    John

  20. James Sexton says:

    Hey fellas! Instead of relying on a very unreliable source. Why not just go to the source for the temp data…. Here’s GISS http://data.giss.nasa.gov/gistemp/tabledata_v3/GLB.Ts+dSST.txt

    For some fun, about the temp abatement, I would submit that there’s not been any significant warming…. evuh!!!!

    I’ve plotted the GISS temps as they would appear on an alcohol thermometer, and I’ll be darned if I can see any significant warming. Even embiggified!!!!

  21. Coalsoffire says:

    It’s dead, Jim.

  22. Jimbo says:

    MattN says:
    March 5, 2013 at 9:17 am

    I am 100% positive that I remember Gavin stating in a post at Realclimate that if there was no warming for 10 years, that would indicate the models were wrong.

    This is the closest I found: [my bold]

    57. OK, simply to clarify what I’ve heard from you.

    (1) If 1998 is not exceeded in all global temperature indices by 2013, you’ll be worried about state of understanding

    (2) In general, any year’s global temperature that is “on trend” should be exceeded within 5 years (when size of trend exceeds “weather noise”)

    (3) Any ten-year period or more with no increasing trend in global average temperature is reason for worry about state of understandings

    I am curious as to whether there are other simple variables that can be looked at unambiguously in terms of their behaviour over coming years that might allow for such explicit quantitative tests of understanding?

    [Response: 1) yes, 2) probably, I'd need to do some checking, 3) No. There is no iron rule of climate that says that any ten year period must have a positive trend. The expectation of any particular time period depends on the forcings that are going on. If there is a big volcanic event, then the expectation is that there will be a cooling, if GHGs are increasing, then we expect a warming etc. The point of any comparison is to compare the modelled expectation with reality - right now, the modelled expectation is for trends in the range of 0.2 to 0.3 deg/decade and so that's the target. In any other period it depends on what the forcings are. - gavin]

    Comment by Daniel Klein — 29 Dec 2007 @ 11:40 AM
    http://www.realclimate.org/?comments_popup=497#comment-78146x

    If 1998 is not exceeded this year then Gavin Schmidt agrees that he would be worried about state of understanding. Just under 10 months to go then before Warmists called him a ‘denier’ / sarc.

  23. JPS says:

    no data should be presented past 2005. did you not receive the memo?

  24. Scott Scarborough says:

    Leo,
    Did James Hansen wait for an ENSO adjusted 15 year temperature rise before he made his presentation to Congress in 1988? (I really don’t know the answer to that).

  25. RESnape says:

    Leo Morgan says:
    March 5, 2013 at 10:15 am

    The quote is talking about 15 years of absence of warming from ENSO- adjusted data sets, not 15 years of absence of warming from raw temperature measurements. The second is what I took it to mean, and how most skeptical users of the quote have presented it as meaning. But that just plain wrong.
    —————————————-

    Your comprehension is somewhat adrift because the quote does not relate to ENSO adjusted data. In essence the quote means that if the ‘predicted’ (i.e. the simulation) trend of warming is not supported by the observed data then the models are wrong.

    To reiterate:
    ”The simulations rule out (at the 95% level) zero trends for intervals of 15 yr or more, suggesting that an observed absence of warming of this duration is needed to create a discrepancy with the expected present-day warming rate.”

  26. wbrozek says:

    Leo Morgan says:
    March 5, 2013 at 10:15 am
    I am very angry about the NOAA quote above.

    Thank you for your comments. RSS and UAH show results that are a bit different from each other. Below, I will illustrate what RSS shows.

    The 1998 El Nino was cancelled out by the La Ninas that were before and after it so nature in effect took care of the ENSO issue in my opinion. See the straight lines for RSS from 1997 and from about three years later. So it is not as if the slope would be positive if we just got rid of 1998. See:

    http://www.woodfortrees.org/plot/rss/from:1997/plot/rss/from:1997/trend/plot/rss/from:2000.17/trend

    I am not going to get into a discussion on semantics as to what was meant or not meant as this has had a very extensive discussion on other posts about a month ago. But I just want to say this. My interpretation is that we can be more than 95% certain the models are wrong at this point, at least based on three data sets at the moment. But even if NOAA never made any such statement, Ben Santer in effect said that if the slope is 0 for 17 years, then something is wrong with the models. This is totally consistent with NOAA’s statement. See:
    http://www.agu.org/pubs/crossref/2011/2011JD016263.shtml

    “A single decade of observational TLT data is therefore inadequate for identifying a slowly evolving anthropogenic warming signal. Our results show that temperature records of at least 17 years in length are required for identifying human effects on global-mean tropospheric temperature.”

    We are not there yet, but RSS has reached 16 years and 1 month to the end of January.

  27. Jay says:

    I would like to hear Steve McIntyre’s take on these analyses. Specifically the 95% confidence levels and the use of 2 sigma. Is the sigma just calculated with the usual std. deviation formula?

    I thought temperature records were auto-correlated, so such a simplistic sigma is not the correct treatment of variation.

    Many astute comments above…
    Adjustments to the data-yup that casts a whole cloud over the no trend.
    Cooling- I can see the curves bending over to cooler in the next 10-20 years is the solar crowd is correct.
    Imagine if draconian carbon cuts had been enacted 10 years ago-Yes, they would be claiming credit.

  28. Jimbo says:

    Here are some more pertinent quotes from Dr. Phil Jones on global temperature since 1998.

    Dr. Phil Jones – CRU – 5th July, 2005
    “The scientific community would come down on me in no uncertain terms if I said the world had cooled from 1998. OK it has but it is only 7 years of data and it isn’t statistically significant….”
    http://www.assassinationscience.com/climategate/1/FOIA/mail/1120593115.txt

    Dr. Phil Jones – CRU – 7th May, 2009
    ‘Bottom line: the ‘no upward trend’ has to continue for a total of 15 years before we get worried.’
    Cru emails

    Dr. Phil Jones – CRU – 13th February 2010
    “I’m a scientist trying to measure temperature. If I registered that the climate has been cooling I’d say so. But it hasn’t until recently – and then barely at all. The trend is a warming trend.”
    http://news.bbc.co.uk/2/hi/science/nature/8511701.stm

  29. Jimbo says:

    Here is the source for the 2nd Phil Jones quote:
    http://di2.nu/foia/foia2011/mail/4199.txt

  30. David Schofield says:

    “Jimbo says:
    March 5, 2013 at 10:57 am
    …………………………..
    …………………………………………..

    Dr. Phil Jones – CRU – 7th May, 2009
    ‘Bottom line: the ‘no upward trend’ has to continue for a total of 15 years before we get worried.’
    Cru emails”

    This is a giveaway as to the mindsets of the climate scientists. CAGW is the ‘biggest threat the world faces’ yet they ‘worry’ if the temperature rise stalls? Surely that should be ‘hopeful’ or ‘optimistic’? Or don’t they need to worry about our our future?

  31. anzon says:

    I can have no confidence in temperature readings that are generated by unsynchronised uncalibrated static sensors representing a sample size of <<0.001% of a dynamic environment.

  32. Doug Proctor says:

    Despite the statistical analysis, both skeptics and warmists will determine the answer for themselves the old-fashioned eyeball way, and are reasonable in doing this. Should the temps go up or down in the future, which is what we are interested in, the past becomes somewhat moot.

    The problem is that we are not dealing with a number of events that allow us to determine a probability of anything – and this goes for the IPCC. We are dealing with just one event, the time period from 1880 to present. The warmists would say that we are only dealing with the period of 1965 to present, as that is the “CO2″ warming of their concern. That being the case, the statistics will be determined by endpoints and your consideration of what is going on, i.e. your mental model.

    This is why the eyeball test is reasonable.

    But …. having a model means that you have to interpret certain parts in a certain way. If you are a warmist, and wish to maintain a rising, not a stall, you have to attribute natural variability to explain the post-97 period as such: from 1997 to some time, say 2005, the “natural” variability was in its warm-er phase. From 2005 to present, then, the natural variability has been in its cool-er phase. In this manner you get a rise consistent with your mental model and explain away the deviations from a linear rise coincident with the rise in CO2.

    The problem with the warmist explanatiion is that the longer the non-rise goes on, the longer you have to attribute natural variability to modifying observation, and the longer you do this, the weaker your CO2 forcing has to be relative to natural factors. That reduces your Scenario outcome at 2100 and potentially defuses the crisis (you so wish to happen). You could say that CO2 will come back with a vengence, having built-up a head-of-steam while the breaks are on, but this now requires a sudden shift of warming in excess of the 1975 – 1997 period.

    The warmist model now has a set of explicit targets both for temperatures and timing. (As I see it, this timing is only a couple of years away, but I would allow a 2017 extension if carbon taxes were in a wait-and-see mode for a couple of years).

    On the other hand, as a skeptic, believing that natural factors such as the sun, cloud and oceanic cycles of heat aborption and release account for the majority of the rise since 1965, you have to posit positive factors flipping over to negative factors about 1998. You are then stuck with the cycles you have for causation: the PDO/AMO has a certain cycle, and the solar sunspot/cloud cover (or cloud cover separately as a function of PDO/AMO or GCR) cycles. In this case, based on an/my understanding of the natural variabilities said to be responsible for the post-1965 rise, temperatures have to FALL (not just stall) for CO2 to be shown to have an insignificant effect. Archibald is the most out-there on the temperature drop he envisions (mostly for the wheat belt of the north-central continental USA); by his reckoning, a drop of > 0.4C must occur globally within the next 10 years. A global drop of 0.2C within the next 4 years would be sufficient.

    The skeptic model thus has an explicit set of expectations. A continued stall only means that, models and arguments concerned, nature (including manmade aeorsols) equals the demon CO2. If nature backs off, we could still be doomed to a CAGW hell. The skeptic model cannot accept this by saying we have continued natural factors warming, as this stage has been explicitly tied to a series of cycles that become net negative after about 30 years.

    Statistical arguments about the “stall” are not incorrect, but they are irrelevant in the discussion. They put numbers to what is eyeball worthy but they do not have any predictive value (again, because we are in a one-event situation, as yet unfinished). I do not diminish the passion of the work, or its conclusions, but say that its value, i.e. worth, to the debate is minimal.

    Regardless of this point, I suggest the analysis demonstrates (mathematically) we are near the tipping point of the IPCC narrative vis-a-vis models and observations. Within 5 years one side will be the side of heroes, and the others, the side of goats. The recent behaviour of Gore and Suzuki suggest to me that they are aware that their “goatishness” is more than likely coming to surface: they spend too much time preaching to the paying faithful and too little – none – preaching to those they need to convert to save the future generations of their own seed.

  33. MikeB says:

    Keep in mind that the MET office believes that the 1998 mark will be beaten by 2017.

    Really, this is a new one on me- what is the source of this information? The last I heard in this regard was that the Met. Office forecast in 2009 that

    At least half of the five following years expected to be hotter than 1998, the warmest year on record

    http://www.reuters.com/article/2007/08/09/us-climate-warming-idUSN0837368420070809
    What happened to that prediction? How is it going? Place your bets.

    And here is a short youtube clip of Vicky Pope of the Met.Office actually saying the the same thing on camera, that 3 out of 5 years after 2009 will exceed 1998. Also, as a bonus, she says

    2014 will be 0.3 degrees warmer than 2004

    She also adds, just to make sure….

    These are very strong statements about what will happen over the next 10 years

    Yes they are very strong statements (probably brougnt in lots of extra grant money) ….but unfortunately for Vicky they look rather strongly stupid now!
    Do we get an apology? Will we get a correction? Place your bets.

  34. feet2thefire says:

    About 3-4 years ago, quite a few people were noticing that, with the two or three other steep upslopes in the record, alternating with slight downslopes, that the whole longer record had the appearance of an up-sloping sine curve with a pitch of about 60 years. 60 years ago, in about 1953, we were about 13 years into the 1940-1970 slight downslope. This was all coming out of the Little Ice Age, when one would expect temps to rise at some rate for some unknown time, and this up-sloping sine curve seemed to fit that quite nicely.

    Similarly, the current “stalling” of “global warming” seems to be not only consistent with that but also pretty much right on schedule. BOTH scenarios – stalling and up-sloping since curve – refute anthropogenic causes to the global warming that has been occurring since about 1800. If warming has stalled, the warmists have a problem (and they are well aware of it). If there is an up-sloping cine curve that predates 1900 by a good bit, they have nothing to hang their hats on.

    I rather like the up-sloping sine curve idea, and until something better comes along, that is where my money is being bet. It INCLUDES “stalling” periods for half of every 60-year period. There is a LOT more rationale to that scenario than blaming the warming on CO2, which is such a tiny percentage of the atmosphere, and not even a majorly active greenhouse gas when compared to water vapor and methane. I mean, if they had chosen to blame anthropogenic land use, most of us wouldn’t even be arguing it.

    If this up-sloping since curve idea is true, we can expect the stalling – quite probably even a slight decrease – to continue for another 17 years, plus or minus a bit. It has happened at least three times; why should’t we be expecting it to happen again? We would then also attribute it to natural causes, not post-1970 industrial emissions.

    My bet is that the upslope won’t happen again until around 2026-2030.

    Hahahaha! That is a long time for Trenberth to worry about missing heat! We have a LOT of laughing ahead of us, folks!

    Long before then, CAGW will be an unfunded ex-laughing stock of science.

    Steve Garcia

  35. wbrozek says:

    UAH update for February.

    The anomaly for February was 0.176, down from 0.504 in January. The 0.504 would be ranked first if it had stayed this way. The 0.176 would be ranked 9th if it stays this way. The average of the two is 0.34. So if the anomaly averaged 0.34 for the rest of the year, it would come in third. As for the longest time the slope is not positive, the numbers are not on WFT yet, however I do not expect a huge change other than raising the 4 years and 7 months to 4 years and 8 months.

    SST update for February.

    According to Bob Tisdale: “The preliminary global sea surface temperature anomalies warmed a slight amount (+0.021 deg C) in the last month.”
    I realize this is not official and may change a bit, but based on this information, there is no doubt in my mind that when the HadSST2 numbers are in for February, that they will show no warming for 16 years from March 1,1997 to February 28, 2013. However this needs to be confirmed.

  36. Here is a very good example of a rural site which has been taking hourly temperature records since 1935.
    Over the 69 years the total mean increase in temperature has been 0.31- 0.32 C.or about a half a degree F over the 69 years recorded. But the study stops in 2003 and I cannot find on the Mt Washington website the continuation of this temperature graph between 2003 to 2013. I have contacted the Mount Washington Observatory to see if this study has been continued to the present. It would be interesting to see if the temperature trend has stalled (In light of the global 10 years+ of stalling) on this truly rural site which has probably not been affected by the Urban Heat Island UHI effect among other factors. The link:
    http://www.mountwashington.org/research/airmap/

  37. Mycroft says:

    great work, Anthony should stick this post in Climate Fails section

  38. D.B. Stealey says:

    David L Hagen says:

    A) Damaging Anthropogenic Global Warming: > 50% of warming due to humans

    That one can be ruled out, as there is no verifiable evidence of any global damage or harm due to the rise in CO2. Thus, CO2 is ‘harmless’.

    In fact, there is no measurable evidence that global warming is due to human activity.

    We are currently in a cool period of the Holocene. But global temperatures have been amazingly constant, only fluctuating by a minuscule 0.8ºC over the past century and a half. By using a normal Y-axis, it is clear that global warming has stalled during this entire time period.

  39. Latitude says:

    “One has to back to the 1940s”………………………………go………one has to ‘go’ back to the 1940′s

    I say forget it…..what’s the point of waiting and seeing for something that wasn’t there in the first place

    ” the MET office believes that the 1998 mark will be beaten by 2017″

    so what if it is………only 150 years ago we were all freezing our butts off……LIA
    ……see those little numbers on the “y” with a decimal in front of them

    Get a grip people, we’re taking about a 1/2 degree here………………

  40. Mr. Africa says:

    as far as I can tell. Gavin’s standard has already been met. He made his statement in December of 2007. We have now experienced 5 years: 2008, 2009, 2010, 2011, and 2012 and not one of them has surpassed 1998 in all 4 indices. Gavin was wrong and should now be “concerned.” Furthermore, this year is looking very unlikely for the hottest year on record based upon the first 2 months of the year and an ENSO neutral scenario. I guess something could suddenly ramp the temperatures up, but that looks unlikely. 2014? maybe.

  41. Jimbo says:

    Strewth, we still got some way to go on the good ship global warming.

    5 March 2013 “Giant camel fossil found in Arctic”
    http://www.bbc.co.uk/news/science-environment-21673940

    http://dx.doi.org/10.1038/ncomms2516

  42. RossP says:

    Well done Werner. I like the idea of using the SsK tools –using alarmists tools to argue against them is the ultimate winner. There are comments above about using adjusted data —thats good to because we all know the direction of the adjustments ( forget how valid they are for a moment). Just like using the Ssk tool –if the adjusted data can be used against them like you have shown then that is another winner.
    Anthony , I would encourage you to publish Werners monthly update EVERY month. Regular readers might get a bit “bored” with it but they are not the ones that need convincing.
    The others can argue whether it it is stalled , flat , paused or still warming slightly but the reality is if the CO2 measurements are correct then the AGW theory as presented by the IPCC and others is WRONG. Temperatures should have continued increasing over the past 15 years at much greater rate with the increased CO2

  43. geran says:

    They have been adjusting the temps higher for so long that now we look cooler. That is why they are changing to climate “change”. So now they will start adjusting temps lower?

    I’m so confused, I must be a major-skeptic….

  44. wbrozek says:

    MikeB says:
    March 5, 2013 at 11:36 am
    Keep in mind that the MET office believes that the 1998 mark will be beaten by 2017.
    Really, this is a new one on me- what is the source of this information?

    See: http://wattsupwiththat.com/2013/01/08/the-other-big-story-today-bbc-forced-to-admit-global-warming-static/

    “The UK Met Office has revised one of its forecasts for how much the world may warm in the next few years.
    It says that the average temperature is likely to rise by 0.43 C by 2017 – as opposed to an earlier forecast that suggested a warming of 0.54C.
    The forecasts are all based on a comparison with the average global temperature over the period 1971-2000.”
    Using 1971 to 2000, the 1998 mark was 0.40.

  45. Werner Brozek says: March 5, 2013 at 9:16 am
    JTF, I just have a concern about the size of the graphs. When you click on them, they are good, but when viewed as they are, they are twice as big as they should be and just the left half appears. This applies to 4 out of the 5. Can this be fixed? Thanks!

    This is a problem with WordPress.

    PNG images sometimes get stretched this way, other times they present normally. The only way to prevent this is to use GIF or JPG images. GIF’s are best because JPG introduces artifacts in graphs and diagrams.

    I’ve had this problem with my WP site, and one of these days I’ll get around to fixing it.

  46. David L. Hagen says:

    D.B. Stealey
    Re: “there is no measurable evidence that global warming is due to human activity.”

    That is the task that needs to be clearly quantified compared to the other models.

    Global temperatures have been cooling since the Holocene Climatic Optimum
    See images
    We are nearing the end of this holocene warm period and approaching the next glaciation, typical of numerous previous glaciations.

  47. wbrozek says:

    Latitude says:
    March 5, 2013 at 12:49 pm
    “One has to back to the 1940s”………………………………go………one has to ‘go’ back to the 1940′s
    I say forget it…..what’s the point of waiting and seeing for something that wasn’t there in the first place

    I am not sure what you are referring to here. At this point, we do not have to wait for anything since Hadcrut3 has not beaten its 1998 mark by a long shot and it has been way over 10 years.

    1998 was warmest at 0.548;
    2005 was second at 0.482;
    2012 was 10th at 0.406;
    January 2013 is 12th at 0.388 so far.

  48. wbrozek says:

    RossP says:
    March 5, 2013 at 1:18 pm

    Anthony , I would encourage you to publish Werners monthly update EVERY month. Regular readers might get a bit “bored” with it but they are not the ones that need convincing.

    Thank you for your comments. JTF and I have discussed this. One way around it would be to just say at the start that if you are a regular reader and just want to get the new highlights, read rows 7+ on the table.

  49. ”The simulations rule out (at the 95% level) zero trends for intervals of 15 yr or more, suggesting that an observed absence of warming of this duration is needed to create a discrepancy with the expected present-day warming rate.”

    The climate models do not model natural variability. The variability in the models is just an approximation by the modelers of the amount of natural variability they think occurs.

    What’s disturbing is that agencies and many climate scientists seem to think the statement above has scientific validity, when it has no scientific validity at all.

  50. Philip Shehan says:

    People here declare that there has been no warming for the last 17 years of Hadcrut4 data, even though the trend is essentially the same as for four times that period, because the trend for the shorter period is not “statistically significant”.

    Yet all consideration of statistical significance is ignored when declaring that UAH data fro the last 4 years and 7 months shows a pause.

    Trend: -0.006 ±1.441 °C/decade

    Unsurprisingly, for this ludicrously short period, Fisherian statistical significance says the true trend could be between warming of 1.435 and cooling of 1.447 °C/decade. You could fly a 747 through that gap.

    But suddenly no-one cares about that. It’s all about the raw slope.

    http://tinyurl.com/d4jxlth

  51. RERT says:

    As an antidote to the ‘warming stalled’ euphoria, I would opine that the only sensible way to look at a supposed rising temperature with cyclical variability is peak-to-peak or trough-to-trough. That means 0.404 degrees (HADCRUT3) in 52.5 years from 1945 to 1998. The recent hiatus makes no difference to this. Still, I can look at a rate of rise of less than 0.8 degrees C per century and go back to sleep: it really doesn’t matter, provided those nuclear fusion bunnies eventually get their act together…

  52. Latitude says:

    wbrozek says:
    March 5, 2013 at 1:48 pm
    =======
    Werner, the first line is a typo for JTF……..it needs a “go” in there..
    Here’s the whole line makes it easier for JTF to find it….

    “For Hadcrut3, see here. Here you have to do something similar to Hadcrut4, but look at the numbers at the far right. One has to………………………. back to the 1940s to find the previous time that a Hadcrut3 record was not beaten in 10 years or less.”

  53. Werner Brozek says:

    Philip Bradley says:
    March 5, 2013 at 2:28 pm

    What’s disturbing is that agencies and many climate scientists seem to think the statement above has scientific validity, when it has no scientific validity at all.

    Does catastrophic anthropogenic global warming have any scientific validity at all?

  54. Paloma says:

    I just saw this new documentary called CHASING ICE which shows the physical evidence of melting glaciers. Opinions and facts can be disputed but visual evidence cannot. See it to believe it. The film was so beautiful yet terrifying at the same time. A must see.

  55. Gina says:

    Of course, more corrections and adjustments will be done to make this data fall in line. I’ve watched many-a-datasets buck the expected trend, then be later corrected. Certain years in my home town, in the 1800s, are 2 degrees cooler than those same years were before new corrections were applied. The Argo floats data showed cooling, until corrected. Etc.

  56. wbrozek says:

    Philip Shehan says:
    March 5, 2013 at 2:39 pm
    People here declare that there has been no warming for the last 17 years of Hadcrut4 data
    With respect to Hadcrut4, there has been no warming since November 2000 or 12 years and 3 months. There has been no statistically significant warming since July 1994 or 18 years and 7 months. So the “17 years” is somewhere in the middle. It should be noted that if warming is occurring at a half decent pace, then 16 years is enough to achieve statistical significance as shown below for 1995 to 2010:
    Start of 1995 to end 2009: 0.133 +/- 0.144. Warming for 15 years is not significant.
    Start of 1995 to end 2010: 0.137 +/- 0.129. Warming for 16 years is significant.
    Start of 1995 to end 2011: 0.109 +/- 0.119. Warming for 17 years is not significant.
    Start of 1995 to end 2012: 0.095 +/- 0.110. Warming for 18 years is not significant.
    Yet all consideration of statistical significance is ignored when declaring that UAH data fro the last 4 years and 7 months shows a pause.
    Trend: -0.006 ±1.441 °C/decade

    Yes, that is short. My effort has been to show all the facts, even if they do not agree with the main thrust of my article. However I would also like to point out that UAH shows no significant warming for longer than GISS. For UAH, the period of no significant warming is from June 1993, but for GISS, it is from August 1995. Two cold months is all it would take for UAH to have no slope for 12 years.

  57. Werner Brozek says: March 5, 2013 at 9:16 am

    JTF, I just have a concern about the size of the graphs. When you click on them, they are good, but when viewed as they are, they are twice as big as they should be and just the left half appears. This applies to 4 out of the 5. Can this be fixed? Thanks!

    Mike McMillan says: March 5, 2013 at 1:41 pm

    This is a problem with WordPress.

    PNG images sometimes get stretched this way, other times they present normally. The only way to prevent this is to use GIF or JPG images. GIF’s are best because JPG introduces artifacts in graphs and diagrams.

    I’ve had this problem with my WP site, and one of these days I’ll get around to fixing it.

    Mike, thanks for the input, I’ve been struggling with this, as it only seemed to impact WFT and was intermittent, hopefully the conversion to GIFs solves the problem.

    Werner, apologies for the delay in addressing this, hopefully everything looks good now.

    Latitude says: March 5, 2013 at 3:22 pm

    Werner, the first line is a typo for JTF……..it needs a “go” in there..
    Here’s the whole line makes it easier for JTF to find it….

    “For Hadcrut3, see here. Here you have to do something similar to Hadcrut4, but look at the numbers at the far right. One has to………………………. back to the 1940s to find the previous time that a Hadcrut3 record was not beaten in 10 years or less.”

    Corrected, thanks. JTF

  58. D.B. Stealey says:

    This chart shows clearly why HadCRUT4 replaced HadCRUT3: HadCRUT4 shows more global warming.

  59. Werner Brozek says:

    Paloma says:
    March 5, 2013 at 3:41 pm
    I just saw this new documentary called CHASING ICE which shows the physical evidence of melting glaciers.

    It is my understanding that many glaciers have been melting since 1880. However CO2 did not really increase since about 1945. Just because glaciers are melting does not necessarily mean that man has anything to do with it. For example, the ice page today shows the southern sea ice area is 0.614 million square km above normal, but the northern sea ice area is 0.422 million square km below normal, for a net positive amount of 0.192 million square km above normal.

  60. @Werner Brozek
    Speaking of glaciers, has anyone been able to access the Hubbard Glacier monitoring site?:
    http://glacierresearch.com/ … I haven’t been able to for over a year.
    This is the largest tidewater glacier in North America. It has been advancing and increasing in mass since the 1880s. Maybe cherry picking, but it IS the largest tidewater glacier.
    Also the Taku Glacier recognized as the deepest and thickest glacier known in the world, the Taku Glacier is measured at 4,845 feet (1,477 m) thick. It is the largest glacier from the Juneau Icefield. in AK.and it too is advancing. Is that cherry picking, too?
    Haven’t seen any info on Hubbard Glacier since 2007 or maybe a report from 2009..

  61. Anthony Watts says:

    @J. Philip Peterson

    I was able to visit http://glacierresearch.com/ but only if I added security exceptions in browser. Seems it is hosted on a military server and the browser expects a security certificate. Couldn’t get past the issue in Firefox, but was able to in IE8 and in Chrome.

    Do a “proceed anyway” in Chrome from this URL: http://rsgisias.crrel.usace.army.mil/hubbard/glaciers.html

    here is Hubbard: http://rsgisias.crrel.usace.army.mil/hubbard/glaciers.html

  62. KR says:

    The NOAA State of the Climate report you link to is discussing ENSO-adjusted data, both for observed and modeled temperatures. You, in this post, are _not_ – apples and oranges, an invalid comparison.

    If you consider the observed temperature swings with ENSO (http://blog.chron.com/climateabyss/2013/01/global-temperature-anomaly-forecasts-january-2013/), we are right on track with the models.

  63. Philip Shehan says:

    Werner,

    Certainly by luck of the draw, short term periods of 15 to 20 years will produce a “statistically significant” results on occasion. But no one should be the least surprised when they regularly fail to produce a statistically significant result.

    The examples you show of significant/not significant warming are declared so by very slim margins. They are right on the cusp of significant/not significant. (In another comment I pointed out that this is a problem many scientists have with Fisherian measure of statistical significance, a result that can be declared with 95.1% confidence is declared “significant” while a result with 94.9% confidence is not.)

    It is because for short term periods, the signal to noise ratio becomes small so that the noise, which is random dominates the signal.

    In the example I gave of the Hadcrut4 data, the trends for 17 years and 68 years are the same. The peak to peak noise (the distance maximum distance vertical distance of the red temperature data from the trend line) varies from the downward spike at 1977 to the el nino peak of 1998. This covers a larger range than the peak to peak noise for the last 17 years, but the signal in the former case (the vertical temperature range covered by the trend line) is large enough so that the overall signal to noise ratio gives a statistically significant result. For the shorter term, it does not.

    http://tinyurl.com/d4jxlth

    The longer you go back the stronger the signal to noise and the more reliable the result.

    1996 0.091 ± 0.120 °C/decade (blue line on plot)
    1995: 0.098 ± 0.111
    1994: 0.116 ± 0.102 point at which 2σ significance achieved
    1990: 0.144 ± 0.080
    1980: 0.158 ± 0.045
    1970: 0.164 ± 0.031
    1960: 0.132 ± 0.025

    1945: 0.094 ± 0.019 (green line on plot)

    I take your point that you only included the UAH data for 4 years and 7 months for completeness, but it nevertheless emphasises my point here.

    That short term trends are too dependent on the noise level to tell you anything meaningful about the signal, and the shorter the period, the more likely the noise is to take over.

    Trend: -0.006 ±1.441 °C/decade (2σ)
    Trend: -0.156 ±0.682 °C/decade (2σ) Hadcrut4

  64. Werner Brozek says:

    RSS Update

    RSS has just come out for February. The anomaly dropped from 0.442 to 0.194. As I said in the report, the 0.442 value ranked 3rd. The 0.194 value ranks 11th to put it into perspective. The average between these two is 0.318 and would rank 5th if it stayed this way.
    As well, the longest time for a slope that is not positive goes up from 16 years and 1 month to 16 years and 2 months, going from January 1997 to February 2013. This is 194/204 = 95% of the way to Santer’s 17 years.

  65. Philip Shehan says:

    “This indicates that there is a slight chance that cooling has occurred since 1990 according to RSS per graph 1 and graph 2.”

    No. The RSS trend since 1990 is 0.127 ±0.134 °C/decade.

    That is there is a 95% chance that the true trend is between 0.261 and -0.007 °C/decade.

    The probability of the true trend being in the negative (cooling) part of this range is very small.

  66. D.B. Stealey says:

    Shehan still doesn’t get it. global warming has stalled, and all his wishful thinking won’t change that fact.

  67. Werner Brozek says:

    Philip Shehan says:
    March 5, 2013 at 6:52 pm

    I agree with everything you said. Personally, I think the period where the slope is 0 is more meaningful. However it appears that climate science has a certain set of rules as the following question and answer with Phil Jones shows:
    “B – Do you agree that from 1995 to the present there has been no statistically-significant global warming
    Yes, but only just. I also calculated the trend for the period 1995 to 2009. This trend (0.12C per decade) is positive, but not significant at the 95% significance level.”

    In that section, I merely reported what SkS showed. Can you confirm if Phil Jones uses the same sort of program that SkS uses to determine significance?

    You like long term trends and point out that “1945: 0.094 ± 0.019 (green line on plot)” At this rate of 0.094/decade, it would take 128 years to increase the global temperature to 2 C from the present 0.8 C. It looks like we have nothing to worry about! Is that not good news?

  68. wbrozek says:

    Philip Shehan says:
    March 5, 2013 at 7:43 pm

    “This indicates that there is a slight chance that cooling has occurred since 1990 according to RSS per graph 1 and graph 2.”
    No. The RSS trend since 1990 is 0.127 ±0.134 °C/decade.
    That is there is a 95% chance that the true trend is between 0.261 and -0.007 °C/decade.
    The probability of the true trend being in the negative (cooling) part of this range is very small.

    It seems as if you are splitting hairs over my wording over what “a slight chance” means? Correct me if I am wrong here. 0.007 is 0.007/0.268 is 2.6% of the total in the 95% range, right? And there is a 2.5% chance the slope is less than -0.007, right? So if that is the case, then there is a 2.5 + 2.6 = 5.1% chance the slope is negative, correct? Is that not a “slight chance” that cooling has occurred?

  69. Werner Brozek says:
    March 5, 2013 at 3:33 pm
    Philip Bradley says:
    March 5, 2013 at 2:28 pm

    Does catastrophic anthropogenic global warming have any scientific validity at all?

    It does, to the extent it derives from a scientific theory with empirical support.

    You may think it is alarmist hogwash, as I do. But from a scientific perspective, the main problem is lack of empirical support. The theory itself (which I have other issues with) does indeed predict warming that could be described as catastrophic.

  70. D.B. Stealey says:

    Philip Bradley says:

    “It does, to the extent it derives from a scientific theory with empirical support.”

    I’m sorry, Philip, but that is not a scientific “theory”. It is not even a “hypothesis”, because it is not falsifiable or testable.

    AGW [and the even more preposterous "catastrophic AGW"] is merely a “conjecture”. It is an opinion; an evidence-free assertion. Without verifiable, testable measurements, AGW [or CAGW] is simply speculation.

    Wake me when the alarmist crowd comes up with verifiable measurements of “AGW”. Until then, AGW [and CAGW] just feeds their fevered imaginations.

  71. Werner Brozek says:

    Philip Bradley says:
    March 5, 2013 at 8:24 pm

    The theory itself (which I have other issues with) does indeed predict warming that could be described as catastrophic.

    My understanding is that the theory says that a doubling of CO2 without any feedbacks increases warming by 1 C. It is only the presumed positive feedbacks due to extra water vapour that make warming catastrophic. In my opinion, both Dr. Spencer and planet Earth have proven that the feedbacks are negative and not positive so we will never have catastrophic global warming. Think of it like applying Le Chatelier’s Principle to planet earth. For more on this, see:
    http://motls.blogspot.ca/2007/11/le-chateliers-principle-and-natures.html#more

  72. wbrozek says:

    KR says:
    March 5, 2013 at 5:40 pm

    If you consider the observed temperature swings with ENSO (http://blog.chron.com/climateabyss/2013/01/global-temperature-anomaly-forecasts-january-2013/), we are right on track with the models.

    Here is what was said for Hadcrut4:

    “My HadCRUTv4 forecast for 2013 is +0.59 +/- .08 C.  This too would be the warmest global anomaly in this data set, breaking the record set in 2010 by +0.05 C.  Again, the odds of setting a new record are about 2 in 3.  My forecast for 2013 is 0.15 C warmer than the observed value for 2012.”

    Here are some relevant facts today: The sun is extremely quiet; ENSO has been between 0 and -0.5 since the start of the year; it takes at least 3 months for ENSO effects to kick in and the January anomaly was 0.433 which would rank it in 10th place. Granted, it is only 1 month, but you are not going to set any records starting the race in 10th place. So even if a 1998 type El Nino started to set in tomorrow, it would be at least 4 or 5 months for the maximum ENSO reading to be reached. Then it would take at least 3 more months for the high ENSO to be reflected in Earth’s temperature. How hot would November and December then have to be to set a new record? In my opinion, the odds of setting a new record are more like 1 in a 1000.

  73. Philip Shehan says:

    Werner, Pardon me. I took your meaning to be that there was a slight chance that it was more likely that the trend would be for cooling rather than warming.

  74. Philip Shehan says:

    Werner. With regards to Phil Jones comments:

    BBC: Do you agree that from 1995 to the present there has been no statistically-significant global warming

    Phil Jones: Yes, but only just. I also calculated the trend for the period 1995 to 2009. This trend (0.12C per decade) is positive, but not significant at the 95% significance level. The positive trend is quite close to the significance level. Achieving statistical significance in scientific terms is much more likely for longer periods, and much less likely for shorter periods.

    I assume he is using the same calculation for statistical significance as I am. It is after all a fairly standard formula.

    http://www.skepticalscience.com/trend.php

    I agree with Jones on that statement – that the period in question does not show warming to a 95% confidence level. But he appears to share my reservations on the limitations and usefuleness of Fisherian statistical significance for short term data sets.

    With regard to the trend from 1945 showing a warming trend of “only” 0.094/decade, compared to say the statistically significant trend from 1960 of 0.132/decade, the assumption that you can extrapolate a linear trend to the end of the century is not supported by the IPCC (sorry can’t find a reference for that at the moment). But at the risk of drawing the wrath of those who have expressed distaste for this graph, the record for the past century and a half is non-linear.

    http://www.skepticalscience.com/trend.php

  75. Girma says:

    http://www.woodfortrees.org/plot/hadcrut3vgl/compress:12/plot/gistemp/compress:12/offset:-0.08/detrend:0.04/plot/hadcrut4gl/compress:12/offset:-0.03/detrend:0.02/plot/hadcrut3vgl/mean:732/plot/hadcrut3vgl/mean:252/plot/hadcrut3vgl/mean:252/offset:0.2/plot/hadcrut3vgl/mean:252/offset:-0.2/plot/hadcrut3vgl/scale:0.000001/offset:4/plot/esrl-co2/scale:0.003/offset:-1.03/detrend:-0.22/from:1982/plot/hadcrut3vgl/mean:252/offset:0.015/plot/hadcrut3vgl/mean:732/offset:0.015/plot/esrl-co2/scale:0.003/offset:-1.03/detrend:-0.22/from:1982

    The GMST has a secular (long-term non-periodic variation) component represented by the monotonic curve obtained from the 61-years moving average GMST.

    The GMST has a cyclic component of 60-years period represented by the 21-years moving average GMST.

    The cyclic GMST was at its peaks in 1880’s, 1940’s & 2000’s and at its trough in 1910 and 1970.

    The amplitude of the Cyclic GMST decreases with increase in the moving average period and is zero for moving average period of 61 years. This means that a moving average period of 61 years smoothes out all of the transient GMST and in this case the GMST Trend becomes equal to the Equilibrium GMST.

    The decrease in the magnitude of the cyclic GMST with increase in the moving average period shown above suggests changing the averaging period in the definition of climate from 30-years to 61-years.

    All the oscillations relative to the secular GMST are transient and should be excluded when analyzing the climate. As a result, the whole climate of the 20th century may be completely defined by the Secular GMST curve (Purple curve). Note that there was no change in shape of the Secular GMST before and after mid-20th century, which indicates a single climate pattern existed in the whole of the 20th century.

  76. Solomon Green says:

    “Look at the following and keep in mind that the MET office believes that the 1998 mark will be beaten by 2017. Do you agree?”

    A technical analyst or “chartist” coming from the stock market might say that each of the last four peaks has been higher than its predecessor and all the troughs have been higher than their predecessors, so there is evidence that supports the Met Office’s contention. Perhaps not by 2017 but somewhat later.

    The difference is that stock market prices are directly and immediately affected by human behaviour whereas even climatologists do not claim that human behaviour has such a direct and immediate affect on global temperatures. So forecasting future medium term (let alone long term) global temperatures from such charts is a waste of effort.

    What the charts do tend to show is that the models which, in the late nineties, forecast continued global warming have been getting it wrong for the last fifteen years or so. This is a long enough period to lead any open-minded scientist to query the accuracy of his/her model and, in the absence of a good scientific explanation for its failure, to admit that the model was unsound. At this point, were it not for the grant money involved, the climatogist might reason that, perhaps, CO2 was not leading to the destruction of the world as we know it.

    On the other hand thinking of all the money that the renewables industry might lose should politicians change their minds, the rational climatologist might consider it too dangerous to admit that he/she had been in error. Rather than do this he/she will continue to make arbitrary adjustments to the raw data to remove the impact of known factors on short-term temperature variations (El Niño/southern oscillation, volcanic aerosols and solar variability). If these do not suffice he/she wil,l no doubt, make further adjustments to the raw data to allow, say, for the year’s exceptional snowfall as it affected albedo or for a change in the level of the jet stream or even, who knows, meteor strikes and other acts of nature. After all making such adjustments so as to remove all natural impacts – especially those which serve to increase global temperatures – can always be done in such a manner as to leave a series of increased temperature readings.

    A more interesting question is how many more years of non-significant growth will it take before the first member of the hockey team admits that the evidence points to his/her theory that the CO2 component of AGW global warming having been disastrously exaggerated and that the principal driver of climate change is natural?

    My guess is not in this century.

  77. Michael Moon says:

    2 Sigma is thin proof of anything at all. In High-Energy Physics, 5 sigma is required to be considered for publication but they prefer 6 Sigma. If “Climate Science” even required 2 Sigma we never would have had the Hockey Stick. At 5 Sigma there would be NO “Climate Science,” as there is no proof at this level that we can predict anything about the weather at all, other than that the Sun will rise in the East tomorrow morning, and summers tend to be warmer than winters. A lot of “pin-head angels” on here, Much Ado About Nothing….

  78. Werner Brozek says:

    Philip Shehan says:
    March 6, 2013 at 12:30 am

    No problem!

    Philip Shehan says:
    March 6, 2013 at 1:06 am

    But at the risk of drawing the wrath of those who have expressed distaste for this graph, the record for the past century and a half is non-linear.

    I agree. As Girma showed at 4:38 A.M., (Thanks!) we have a 60 year sine wave superimposed on a slightly rising linear line. At the moment, we seem to be heading down the sine wave. This seems to have gone on for the last 10 years so we may have another 20 years to go before we bottom out.

  79. Taphonomic says:

    Wait, there are data after 2005??

    Someone needs to advise Michael Mann of this development.

  80. DR says:

    Why not apply Craig Loehle’s method out to 2013?
    http://icecap.us/images/uploads/05-loehleNEW.pdf

  81. AndyG55 says:

    Its going to be fun watching the CAGW bletheren as global temperatures start to drop over the next few years.
    We have already seen Marcott’s little piece of statistical chicanery, there will be more to come as they get more and more desperate not to be shown up as total fools.

  82. Anny says:

    I have come to the conclusion that we all have a little blame global warming and its consequences and guilt even more politicians who do not slow down.

    http://www.globalwarmingweb.com/

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