If the global warming era started in June 1988 with Jim Hansen’s drama-queen congressional testimony, then atmospheric temps have been flat 67% of the time since.

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

**Guest Post By Werner Brozek, Edited By Just The Facts**

The graphic above shows 3 lines. The long line shows that RSS has been flat from December 1996 to July 2013, which is a period of 16 years and 8 months or 200 months. The other slightly higher flat line in the middle is the latest complete decade of 120 months from January 2001 to December 2010. The other slightly downward sloping line is the latest 120 months prior from present. It very clearly shows it has been cooling lately, however this cooling is not statistically significant.

In my opinion, if you want to find out what the temperatures are doing over the last 10 or 16 years on any data set, you should find the slope of the line for the years in question. However some people insist on saying global warming is accelerating by comparing the decade from 2001 to 2010 to the previous decade. They conveniently ignore what has happened since January 2011. However, when one compares the average anomaly from January 2011 to the present with the average anomaly from January 2001 to December 2010, the latest quarter decade has the lower number on all six data sets that I have been discussing. Global warming is not even decelerating. In fact, on all six data sets, cooling is actually taking place.

The numbers for RSS for example are as follows: From January 2001 to December 2010, the average anomaly was 0.265. For the last 31 months from January 2011 to July 2013, the average anomaly is 0.184. The difference between these is -0.081. I realize that it is only for a short time, but it is long enough that there is no way that RSS, for example, will show a positive difference before the end of the year. In order for that to happen, we can use the numbers indicated to calculate what is required. Our equation would be (0.184)(31) + 5x = (0.265)(36). Solving for x gives 0.767. This is close to the highest anomaly ever recorded on RSS, which is 0.857 from April 1998. With the present ENSO conditions, there is no way that will happen.

A word to the wise: do not even mention accelerated global warming until the difference is positive on all data sets.

I have added rows 23 to 25 to the table in Section 3 with the intention of updating it with every post. This table shows the numbers that I have given for RSS above as well as the corresponding numbers on the other five data sets I have been discussing. Do you feel this would be a valuable addition to my posts?

**(Note: If you read my last article and just wish to know what is new with the July data, you will find the most important new things from lines 7 to the end of the table.)**
Below we will present you with the latest fact, the information will be presented in three sections and an appendix. The first section will show for how long there has been no warming on several data sets. The second section will show for how long there has been no statistically significant warming on several data sets. The third section will show how 2013 to date 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). 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 8 years and 7 months to 16 years and 8 months.

1. For GISS, the slope is flat since February 2001 or 12 years, 6 months. (goes to July)

2. For Hadcrut3, the slope is flat since April 1997 or 16 years, 4 months. (goes to July)

3. For a combination of GISS, Hadcrut3, UAH and RSS, the slope is flat since December 2000 or 12 years, 8 months. (goes to July)

4. For Hadcrut4, the slope is flat since December 2000 or 12 years, 8 months. (goes to July)

5. For Hadsst2, the slope is flat since March 1997 or 16 years, 4 months. (goes to June) (The July anomaly is out, but it is not on WFT yet.)

6. For UAH, the slope is flat since January 2005 or 8 years, 7 months. (goes to July using version 5.5)

7. For RSS, the slope is flat since December 1996 or 16 years and 8 months. (goes to July)**RSS is 200/204 or 98% of the way to Ben Santer’s 17 years.**

The next link shows just the lines to illustrate the above for what can be shown. 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 C 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.

Source: WoodForTrees – Paul Clark – click 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 statistically significant warming according to their criteria. The numbers below start from January of the year indicated. Data go to their latest update for each set. 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 statistical significance.)

The situation with GISS, which used to have no statistically significant warming for 17 years, has now been changed with new data. GISS now has over 18 years of no statistically significant warming. As a result, we can now say the following: On six different data sets, there has been no statistically significant warming for between 18 and 23 years.

For RSS the warming is **not** statistically significant for over 23 years.

For RSS: +0.120 +/-0.129 C/decade at the two sigma level from 1990

For UAH the warming is **not** statistically significant for over 19 years.

For UAH: 0.141 +/- 0.163 C/decade at the two sigma level from 1994

For Hadcrut3 the warming is **not** statistically significant for over 19 years.

For Hadcrut3: 0.091 +/- 0.110 C/decade at the two sigma level from 1994

For Hadcrut4 the warming is **not** statistically significant for over 18 years.

For Hadcrut4: 0.092 +/- 0.106 C/decade at the two sigma level from 1995

For GISS the warming is **not** statistically significant for over 18 years.

For GISS: 0.104 +/- 0.106 C/decade at the two sigma level from 1995

For NOAA the warming is **not** statistically significant for over 18 years.

For NOAA: 0.085 +/- 0.102 C/decade at the two sigma level from 1995

If you want to know the times to the nearest month that the warming is **not** statistically significant for each set to their latest update, they are as follows:

RSS since August 1989;

UAH since June 1993;

Hadcrut3 since August 1993;

Hadcrut4 since July 1994;

GISS since January 1995 and

NOAA since June 1994.

Section 3

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

1. 12ra: This is the final ranking for 2012 on each data set.

2. 12a: Here I give the average anomaly for 2012.

3. 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. ano: This is the average of the monthly anomalies of the warmest year just above.

5. mon: 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. ano: This is the anomaly of the month just above.

7. y/m: This is the longest period of time where the slope is not positive given in years/months. So 16/2 means that for 16 years and 2 months the slope is essentially 0.

8. sig: This is the whole number of years for which warming is **not statistically significant** according to the SkS criteria. The additional months are not added here, however for more details, see Section 2.

9. Jan: This is the January, 2013, anomaly for that particular data set.

10. Feb: This is the February, 2013, anomaly for that particular data set, etc.

21. ave: This is the average anomaly of all months to date taken by adding all numbers and dividing by the number of months. However if the data set itself gives that average, I may use their number. Sometimes the number in the third decimal place differs by one, presumably due to all months not having the same number of days.

22. rnk: 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 30 or 35 minutes into a game. Due to different base periods, the rank may be more meaningful than the average anomaly.

23.new: This gives the average anomaly of the last 31 months on the six data sets I have been discussing, namely from January 2011 to the latest number available.

24.old: This gives the average anomaly of the 120 months before that on the six data sets I have been discussing. The time goes from January 2001 to December 2010.

25.dif: This gives the difference between these two numbers.

Note that in every single case, the difference is negative. In other words, from the previous decade to this present one, global warming is NOT accelerating. As a matter of fact, cooling is taking place.

Source | UAH | RSS | Had4 | Had3 | Sst2 | GISS |

1. 12ra | 9th | 11th | 9th | 10th | 8th | 9th |

2. 12a | 0.161 | 0.192 | 0.448 | 0.406 | 0.342 | 0.57 |

3. year | 1998 | 1998 | 2010 | 1998 | 1998 | 2010 |

4. ano | 0.419 | 0.55 | 0.547 | 0.548 | 0.451 | 0.66 |

5. mon | Ap98 | Ap98 | Ja07 | Fe98 | Au98 | Ja07 |

6. ano | 0.66 | 0.857 | 0.829 | 0.756 | 0.555 | 0.93 |

7. y/m | 8/7 | 16/8 | 12/8 | 16/4 | 16/4 | 12/6 |

8. sig | 19 | 23 | 18 | 19 | | 18 |

Source | UAH | RSS | Had4 | Had3 | Sst2 | GISS |

9. Jan | 0.504 | 0.441 | 0.450 | 0.390 | 0.283 | 0.63 |

10.Feb | 0.175 | 0.194 | 0.479 | 0.424 | 0.308 | 0.50 |

11.Mar | 0.183 | 0.205 | 0.405 | 0.384 | 0.278 | 0.58 |

12.Apr | 0.103 | 0.219 | 0.427 | 0.400 | 0.354 | 0.48 |

13.May | 0.077 | 0.139 | 0.498 | 0.472 | 0.377 | 0.56 |

14.Jun | 0.269 | 0.291 | 0.451 | 0.426 | 0.304 | 0.66 |

15.Jul | 0.118 | 0.222 | 0.514 | 0.490 | 0.468 | 0.54 |

Source | UAH | RSS | Had4 | Had3 | Sst2 | GISS |

21.ave | 0.204 | 0.244 | 0.459 | 0.427 | 0.339 | 0.564 |

22.rnk | 6th | 8th | 9th | 8th | 10th | 10th |

23.new | 0.158 | 0.184 | 0.436 | 0.385 | 0.314 | 0.562 |

24.old | 0.187 | 0.265 | 0.483 | 0.435 | 0.352 | 0.591 |

25.dif | -.029 | -.081 | -.047 | -.050 | -.038 | -.029 |

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

Appendix

In this section, we summarize the data for each set separately.

RSS

The slope is flat since December 1996 or 16 years and 7 months. (goes to June) RSS is 199/204 or 97.5% of the way to Ben Santer’s 17 years.

For RSS the warming is not statistically significant for over 23 years.

For RSS: +0.122 +/-0.131 C/decade at the two sigma level from 1990.

The RSS average anomaly so far for 2013 is 0.248. This would rank 7th 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 statistically 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.

Graph 1 and

graph 2.

UAH

The slope is flat since July 2008 or 5 years, 0 months. (goes to June)

For UAH, the warming is not statistically significant for over 19 years.

For UAH: 0.139 +/- 0.165 C/decade at the two sigma level from 1994

The UAH average anomaly so far for 2013 is 0.219. This would rank 4th 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, 7 months. (goes to May.)

For Hadcrut4, the warming is not statistically significant for over 18 years.

For Hadcrut4: 0.093 +/- 0.107 C/decade at the two sigma level from 1995

The Hadcrut4 average anomaly so far for 2013 is 0.450. This would rank 9th if it stayed this way. 2010 was the warmest at 0.547. The highest ever monthly anomaly was in January of 2007 when it reached 0.829. The anomaly in 2012 was 0.448 and it came in 9th.

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 April 1997 or 16 years, 2 months (goes to May, 2013)

For Hadcrut3, the warming is not statistically significant for over 19 years.

For Hadcrut3: 0.091 +/- 0.110 C/decade at the two sigma level from 1994

The Hadcrut3 average anomaly so far for 2013 is 0.414. This would rank 9th 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 0.405 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

For Hadsst2, the slope is flat since March 1, 1997 or 16 years, 2 months. (goes to April 30, 2013).

The Hadsst2 average anomaly for the first four months for 2013 is 0.306. This would rank 11th 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

this.
GISS

The slope is flat since February 2001 or 12 years, 5 months. (goes to June)

For GISS, the warming is not statistically significant for over 18 years.

For GISS: 0.105 +/- 0.110 C/decade at the two sigma level from 1995

The GISS average anomaly so far for 2013 is 0.57. This would rank 9th if it stayed this way. 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

So far in 2013, there is no evidence that the pause in global warming has ended. As well, all indications are that RSS will reach Santer’s 17 years in three or four months. The average rank so far is 8.5 on the six data sets discussed here. ENSO has been neutral all year so far and shows no signs of changing. The sun has been in a slump all year and also shows no sign of changing. As far as polar ice is concerned, the area that the north is losing is close to what the south is gaining. So the net effect is that there is little overall change and this also shows no sign of changing.