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Saturday, June 4, 2016

Troposphere temperatures for May 2016

Sou | 11:42 PM Go to the first of 15 comments. Add a comment
The troposphere temperatures are out for May 2016. The lower troposphere as UAH v6 beta 5 and RSS TLT v3.3. As last month, this report also covers RSS TTT for the troposphere.

In all records, the May global anomaly dropped again, as El Nino dissipated. In the lower troposphere (UAH beta v6.05) and the troposphere (RSS TTT) the May anomaly is lower than it was in 1998.

Troposphere temperature (RSS TTT v4) chart


First here is RSS TTT with the latest dataset, version 4. TTT seems to be measure more of the troposphere than TLT (that is, it has a greater vertical profile) with less of the stratosphere than the mid-troposphere data (TMT). It shows a higher rate of warming than RSS v3.3 and higher than UAH.

Hover the cursor (arrow) over the plots to see the data points, trend etc.

The chart below is the average of the 12 months to May, from June 1979 to May 1980, through to June 2015 to May 2016.
Figure 1 | Troposphere temperature for 12 months to May (TTT). Anomaly is from the 1979-1998 mean. Data source: RSS
TTT is a multi-channel combined product made by calculating a linear combination of TMT and TLS. TTT = 1.1*TMT - 0.1*TLS. This combination has the effect of reducing the influence of the lower stratosphere, as shown Figure 3. In the simpler TMT product, about 10% of the weight is from the lower stratosphere. Because the lower stratosphere is cooling at most locations, this causes the decadal trends in TMT to be less than the trends in the mid and upper troposphere. TTT was proposed by Fu and Johanson, 2005.

While on TTT, here is the chart just for the month of May. It is just a tad cooler than May 1998:
Figure 2 | Troposphere temperature for the month of May only (TTT). Anomaly is from the 1979-1998 mean. Data source: RSS


Lower troposphere


The rest of the charts are from UAH beta v6.5. This is almost identical to the old version of RSS, which is v3.3, so is likely to be updated at some time. (Other RSS data sets, like TTT are now at version 4.)

The chart below is the average of the 12 months to May, from June 1979 to May 1980, through to June 2015 to May 2016.

Figure 3 | Lower troposphere temperature for 12 months to May. Anomaly is from the 1981-2010 mean. Data source: UAH

Below is the UAH chart for the month of May only for each year going back to 1979. The anomaly was 0.55 °C above the 1981-2010 mean, which was 0.09 °C lower than the previously hottest May in 1998 (0.64 °C):

Figure 4 | Lower troposphere temperature for the month of May only. Anomaly is from the 1981-2010 mean. Data source: UAH



Comparing recent El Nino years


Below are charts comparing El Nino years with this current El Nino for RSS (TTT) and UAH lower troposphere. The troposphere temperature peaked in February. In 1998 the peak was in April.

Figure 5 | Troposphere temperature for selected El Nino years (TTT). Anomaly is from the 1979-1998 mean. Data source: RSS


Figure 6 | Lower troposphere temperature for selected El Nino years. Anomaly is from the 1981-2010 mean. Data source: UAH

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From the WUWT comments


This is a selection of comments from the WUWT copy and paste of Roy Spencer's latest article about the UAH lower troposphere record (archived here). There was the usual speculation about the reappearance of a "pause".

Dinsdale  thinks that the record setting rapid rise in temperature is "natural".
June 1, 2016 at 1:35 pm
More proof that the “warmest evah” is just natural variation and can’t be the fault of man.

WUWT-ers don't understand how climate models work. They seem to think that ENSO events aren't a feature. That's not the case.  It started with Curious George who wrote:
June 1, 2016 at 1:49 pm
Do models forecast El Niño and its effects?


MarkW  gets it partly right and mostly wrong (see below).
June 1, 2016 at 1:56 pm
El Nino/La Nina are considered “weather” and aren’t factored into the models.


goldminor gets it even more wrong:
June 1, 2016 at 2:35 pm
The fact that the ENSO regions aren’t factored in to the models is one of the reasons why the models can never work. I used to be puzzled that the ENSO changes could be so easily dismissed by the alarmists and climate modelers. If the ENSO region effects went away, then the world’s climate and weather would be vastly different. 

Werner Brozek isn't mathematically inclined. He doesn't bother with linear least squares regression to determine a trend. (The temperature of the lower troposphere reported as UAH TLT beta v6.05 is rising at 0.12 C/decade or 1.2 C a century, not 0.42 C a century - see the charts above).
June 1, 2016 at 2:25 pm
The January to May 5 month average for 1998 was
(0.479 + 0.653 + 0.475 + 0.743 + 0.643)/5 = 0.5986.
The January to May 5 month average for 2016 is
(0.540 + 0.832 + 0.734 + 0.715 + 0.55)/5 = 0.6742.
This is a difference of 0.0756 C over 18 years which amounts to 0.42 C/century.
However this will be lower next month since anomalies are plummeting and the 2016 May value of 0.55 is already below the 1998 June value of 0.575.
Will 2016 beat the 1998 record? Stay tuned. 

15 comments:

  1. Werner Brozek's misconception that you can tell how much hotter the Earth has gotten by comparing the anomalies in this El Nino to the anomalies from 1998 seems to be a common denier tactic these days. I've got a denier friend I discuss climate with, and he uses the same tactic.

    Oddly, this is only a few months after they insisted on using least-squares regression to show there had been no warming at all since 1997. Least-squares trendliens are now completely out of fashion.

    Out of fashion also is the RSS dataset that deniers used to use. Now UAH is the only valid dataset.

    Straw-grasping seems rampant.

    ReplyDelete
    Replies
    1. I see nothing wrong in doing peak-to-peak comparisons between the recent el Nino and 1998. The recent el Nino is not stronger, it is similar in ONI but weaker in MEI, SOI, warm water volume, etc.
      Thus, it is surprising that the peak to peak change in the surface indices (about 0.4-0.5 C, is larger than expected by the CMIP5 model average trend between 1998 and 2016.
      The free troposphere 850-300 mbar show a peak to peak increase of 0.6 C, according to the Ratpac A radiosonde dataset (year to date through April comparison).

      The peak to peak changes in UAH v6 TLT and RSS TLT are more or less flat, probably due to unchecked drifts.
      The RSS TTT v4 dataset with improved diurnal drift correction show a larger peak to peak change (about 0.2 C), but still suffer from the NOAA14/NOAA15 merging uncertainty issue.
      RSS v4 stopped using NOAA-15 in 2011, so IMO data are relatively reliable from 2011 on...

      Delete
    2. There's nothing wrong per se with making comparisons between El Nino periods. What is wrong was when Werner wrote: "...which amounts to 0.42 C/century." What that says is that he's taken the difference between two five month averages and indicated that was the same as the long term temperature trend, which is not just silly, it's wrong. All he was actually showing was the difference between two short periods each of five months, not a trend. You could possibly use it to see the relative strength of El Nino's, except that you'd have to deduct the long term warming trend first. It would be a crude measure even then.

      The trend for RSS TTT (troposphere) is 1.8 C/century. For UAH TLT v6.05 beta is 1.2 C/century. Both are much higher than Werner's 0.42 C/century.

      Delete
    3. Instead of taking comparisons between a pair of El Nino events, it's really better to look at patterns of the ENSO behavior over the entire recorded history.

      http://contextEarth.com/2016/05/13/enso-phase-reversal/

      The problem with just a pair is that it can show agreement simply due to chance.

      Delete
    4. Sou, I see your point..
      My point was more that Werner must do some serious cherrypicking to arrive in the low 0.42 C/century estimate. He has to choose either a dataset no longer endorsed by its producers due to drifts, or an unpublished beta-product that has such a low TMT- and TLT-trend during the AMSU-period that it actually proves the elusive upper troposphere hotspot (ie the TTP-trend (tropopause layer) is higher).

      A "Werner"-practice with Gistemp loti would give a peak to peak trend of 2.9 C/century, or with Ratpac A 850-300 mbar, 3.3 C/century..

      Delete
  2. Clearly, all this warming is caused by the exhaust gased created by the power plant producing the electricity used to create this useless blog. Either shut it down as a service to humanity or face a class action lawsuit!

    ReplyDelete
    Replies
    1. Class action lawsuit? Scarey! You 'don't know nuffink' if your knowledge of climate science is as limited as your knowledge of group litigation and when it can be applied. And 'Ayatollah Obama'? Really? It just shows the low base from which you're launching your vitriol. That's a fail for you.

      Delete
    2. At least "Ayatollah Obama" aknowledges, although probably unintentionaly, that the warming is caused by exhaust gases (aka CO2) from power plants.

      Delete
    3. You are desperately out of your depth here AO. Before you comment here again have a stab at understanding the discussion.

      Your comment was so mindless and offensive even (the new and improved) WUWT would have modded you out of existence.

      If you're looking to understand this planet through WND's lens then good luck mate. You are in desperate need of it.

      Delete
    4. Lol @ Ayatolla Obama

      I doubt it is his real name either!!

      Delete
    5. I'm still trying to figure out if the OP was intended as a humorous pastiche of Republican lunacy.

      Delete
    6. @ Millicent
      I took it that it was intended as a humorous pastiche of Republican lunacy although I would not limit it to US Republicans. Other countries have almost as lunatic deniers.

      Unfortuntely Poe's Law applies so AO could have raving insane, er I mean, serious

      Delete
    7. I'd also assumed this was satire. Poe's Law indeed!

      Delete
    8. If they can no longer communicate with us, does this mean Homo Libertarian is splitting into its own evolutionary niche separate from the rest of Homo Sapiens?

      Delete
  3. Regarding the satellite-based charity 'climate bet' between Skeptical Science's Rob Honeycutt and Pierre Gosselin of the ironically named 'NoTrickZone' website: http://www.skepticalscience.com/climate-bet-for-charity-2016-update.html

    For what it's worth, the May 2016 update from UAH and RSS makes the current decade (2011-20) warmer than the previous one (2001-10) 'to date', no matter what way you measure it.

    The current decade already was warmer using a running decadal average (tracking back 10 years from the most recent month); but even if you use the sceptics' preferred method of comparing the running monthly averages separately (we're now up to month 65 of 120), then the current decade is also now warmer than the previous one for the first time: http://oi68.tinypic.com/2vd2mo7.jpg

    Even as satellite temperatures fall back over the course of 2016, the running average temperature of the current decade will continue to surge past that of the previous one for several months ahead at least.

    ReplyDelete

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