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Tuesday, April 5, 2016

Lower troposphere temperatures March 2016

Sou | 2:14 PM Go to the first of 10 comments. Add a comment
The lower troposphere temperatures are out for March 2016, as UAH v6 beta 5 and RSS v3.3. In both cases the global anomaly is lower than it was for February, but the hottest March in the record. Below are charts for the month of March only for each year going back to 1979. First is RSS lower troposphere. The anomaly was 0.842 °C above the 1979-1998 mean, which was 0.26 °C higher than the previously hottest March in 2010 and 1998 (equal at 0.585 °C):

Figure 1 | Lower troposphere temperature for March only. Data source: RSS

Then UAH lower troposphere. This month the anomaly was 0.73 °C above the 1981-2010 mean, which was 0.21 °C higher than the previous hottest March in 2010 (0.52 °C):

Figure 2 | Lower troposphere temperature for March only. Data source: UAH and Roy Spencer


Comparing recent El Nino years


Below are charts comparing El Nino years with this current El Nino for RSS and UAH lower troposphere. The lower troposphere might or might not have peaked in February. In 1998 the peak was in April.

Figure 3 | Lower troposphere temperature for selected El Nino years. Data source: RSS


Figure 4 | Lower troposphere temperature for selected El Nino years. Data sourceUAH and Roy Spencer


Predicting the peak month


Roy Spencer sometimes has a (pot)shot at predicting what will happen over coming months. In the February report of January temperatures he wrote that January might have been the peak, or not:
We are now approaching peak warmth in the tropics due to El Nino conditions. Only time will tell if warming continues for a few more months, or whether January was the peak.

In the March report of February temperatures he didn't make a prediction and wrote:
The February warmth is likely being dominated by the warm El Nino conditions, which tends to have peak warmth in the troposphere close to February…but it appears that isn’t the whole story, since the tropical anomaly for February 2016 (+0.99 C) is still about 0.3 C below the February 1998 value during the super-El Nino of that year. In addition to the expected tropical warmth, scattered regional warmth outside the tropics led to a record warm value for extratropical Northern Hemispheric land areas, with a whopping +1.46 C anomaly in February…fully 0.5 deg. C above any previous monthly anomaly (!)

In this latest (April) report of March temperatures he predicted that the peak has passed and wrote:
I suspect that February and March represent peak El Nino warmth in the lower troposphere, and the rest of the year will see cooling.

I don't care much for Roy's predictions. Given his prediction for January, I can't see that they are based on the past or any particular understanding of ENSO events and the lower troposphere response.




12 months ending in March each year


Monthly data masks the signal with the noise. The charts below show the 12 month average temperatures to March each year. They should be used with caution because the first three months of this year, which are the last three months of the 12 month average, are likely to be among the highest for the year.

Figure 5 | Lower troposphere temperature for 12 months ending in March. Data source: RSS

Figure 6 | Lower troposphere temperature for 12 months ending in March. Data sourceUAH and Roy Spencer


TTT chart


In the comments, Olaf R suggested posting the TTT data from RSS which is now at version 4. TTT seems to be 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). I've used it to try out Google charts, which are more interactive than the charts I've been using so far. Hover the cursor (arrow) over the plots to see the data points, trend etc.

Like Figures 5 and 6 above, the chart below is the average of the 12 months to March, from April 1979 to March 1980, through to April 2015 to March 2016.
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.

Added by Sou at 11:10 pm 5 April 2016 AEST

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. There was much speculation about the reappearance of a "pause".

ralfellis was the first hopeful:
April 4, 2016 at 11:49 am
The question is – when will the pause reappear? With the inevitable cooling after the el Nino, I would expect the regressively calculated pause to be back by the end of the year.
R

I think when george e. smith talked about the "third warmest" he was referring to the third biggest anomaly, not the actual temperature. Roy Spencer would have confused people with the way he expressed things. (When he wrote the "third warmest month overall compared to seasonal norms" I think he meant the third biggest monthly anomaly not the third warmest month).
April 4, 2016 at 12:57 pm
Well only third warmest; we’re already in a cooling trend !
I don’t think the Monckton Pause ever ends; but I guess it can go to zero months or maybe one month.
Has Christopher given us a recent run of his algorithm; or did it just all fade away except for the grin ??

Nick Stokes informed WUWT readers that the trend won't go negative until/unless the monthly anomaly drops below 0.26 C, which is unlikely.
April 4, 2016 at 1:20 pm
“when will the pause reappear?”
Here’s a way to think about it. Here is a WFT RSS plot since mid-1997:

The regression line currently is about 0.26°C in 2016 and near flat. Every new month above that increases the trend, which became positive in Feb. The trend increase is proportional to the new residual (excess over 0.26). It won’t start decreasing until temperatures go below 0.26. And then, for the trend to go negative, the cumulative sum of deficits (below 0.26) since Feb 2016 would have to exceed the sum of excesses which is currently building fast. Not this year, maybe never (and not within the life of RSSv3.3).

emsnews is not only banking on a La Nina, he or she thinks it will be very cold. (The Australian Bureau of Meteorology isn't so sure.):
April 4, 2016 at 1:23 pm
I am betting on a very cold la Nina. This el Nino is fading very fast.

Some are being cheerful about the spike in lower troposphere temperatures. Latitude wrote:
April 4, 2016 at 11:50 am
beats the h$ll out of freezing to death…. ;)

Patick B is complaining about the lack of error margins. I don't know if he makes the same complaint with every other article at WUWT:
April 4, 2016 at 12:03 pm
One more time – how can you possibly announce such “results” without including properly calculated margins of error. Then once you have margins of error, how does the ranking look? Lots of tied months?
No science without margins of error. You can’t understand anything if you don’t know what you measured. 

Greg picks up on Roy Spencer's sloppy wording about the "third warmest":
April 4, 2016 at 12:04 pm
March 2016 was the warmest March in the satellite temperature record and the third warmest month overall, when compared to seasonal norms,
So it is NOT the third warmest month but the third largest “anomaly”.
Let’s get our facts right. The hottest months are the ones which are …. hottest. 

Tom Halla needs to sack his optometrist:
April 4, 2016 at 12:29 pm
By this UAH database, it looks like the temperature is indistiguishable from flat since 1998. 

Slipstick is amused by the inconsistency of deniers at WUWT:
April 4, 2016 at 1:07 pm
I find all the “this means nothing” naysaying amusing, especially when it is from the same people who use the very same dataset as evidence of a “pause” (which did not, by the way, occur in the oceans, hence the large atmospheric temperature spike from the El Nino). 

David S is deluded. Where do people like him get their crazy notions from?
April 4, 2016 at 2:56 pm
I know that highlighting that this is the third warmest month since the start of satellite data may be of interest but it adds nothing to the climate debate. Unless one extends the analysis to the 19th century and assesses the pre industrial CO2 days and post CO2 days the comment is in fact largely irrelevant to the debate and in fact misleading in the hands of Warmists. Wasn’t the temperatures experienced in the 1930s and 1890s higher than those experienced today? So what benefit to the overall debate ( discussion) is the fact that the last 2 months have been 2 of the warmest in a limited time set? 

The 1890s average was 1.1 °C colder than the average for 2015. The 1930s average was 0.98 °C colder than the average for 2015.

Figure 7 | Surface temperature showing the average for selected periods. Data source: GISS NASA

When asked for evidence, deniers fall back on "lots of" while providing no data or evidence, and weave a conspiracy theory. Gloateus Maximus wrote:
April 4, 2016 at 4:46 pm
Lots of data show higher temperatures in the 1930s than now, but the books have been cooked beyond recognition.

Gloateus Maximus does dig up what he calls "evidence", but it's not. It's only some data for maximum temperatures set in some states in the USA. Nothing to do with global temperatures or long term trends. You'll also notice the inconsistency. Are the books cooked or aren't they?
April 4, 2016 at 4:51 pm
For instance, check out maximum state temperature records from the 19th century through the 1930s:
http://www.ncdc.noaa.gov/extremes/scec/records 

TA lives in an alternate unreality. He or she referred WUWT readers to Steve Goddard's denier blog. Good grief! How desperate are deniers these days? He or she also confused US temperatures with global temperatures when writing about what James Hansen said. Is it any wonder TA didn't provide the link, which would not have supported his claim? When you have to accuse scientists all around the world of fudging every single temperature data set, then you've lurched into Lizard Men territory.
April 4, 2016 at 6:45 pm
seaice1 April 4, 2016 at 4:38 pm wrote: [David S wrote:“Wasn’t the temperatures experienced in the 1930s and 1890s higher than those experienced today?” seaice1 wrote: “No, not according to the data we have.”
The data you refer to must be the adulterated NASA-NOAA temperature data. You are correct that the NASA-NOAA data show the 1930’s as much cooler than today, but we all know that is a BIG LIE! Or most of us, anyway.
seacice1 wrote: “Do you have a data set that says otherwise?
Here you go: http://realclimatescience.com/
You can find all sorts of charts there that show the 1930’s was hotter than 1998. But I guess if you dismiss vukcevic’s chart, then you probably won’t like the charts on this webpage either, because they pretty much say the same general thing: The 1930’s was hotter than any year that has come afterwards.
And if you need an expert to verify that the 1930’s was hotter than 1998, we can turn to none other than Hansen, who said 1934 was hotter than 1998, before he conspired with other climate scientist charlatans/criminals to modify the surface temperature records and erase the fact that the 1930’s was hotter than any subsequent year. If the 1930’s is hotter, then that blows up their human-caused global warming/climate change theory, so they changed the temperature record to make it conform. Where’s RICO when you need it? 
This temperture data modification was done in order to make it look like the Earth’s atmosphere was getting hotter and hotter with each passing year, to assist them in perpetrating the fraud that humans are causing the climate to behave abnormally because humans burn fossil fuels.
This, plus NASA’s prestige has pretty much convinced the gullible in the world, that the climate charlatans are right. Unfortunately for them, the thermometer is not cooperating with them, at least not much. They may be able to falsify some history, but they can’t falsify the data going forward, so the time of fudging the figures is over.
These rewriters of the surface temperature record have done great harm to humanity. They better hope the temperatures rise in the future. 

Deniers just love a good conspiracy theory.

10 comments:

Olof R said...

Good post Sou,

However, Mears et al don't recommend the use of TLT 3.3 due to unchecked drifts:

"The lower tropospheric (TLT) temperatures have not yet been updated at this time and remain V3.3. The V3.3 TLT data suffer from the same problems with the adjustment for drifting measurement times that led us to update the TMT dataset. V3.3 TLT data should be used with caution."

I guess that TTT v4 is the preferred troposphere product until there is a new TLT. In TTT v4 March 2016 is 1.04 C, up by 0.40 from March 1998..

Also, TTT is probably a better comparison to UAH v6 ( more similar weighting curves). The TTT and UAH v6 formulas give similar trends when using channel data from the same supplier (UAH, RSS or STAR)

Sou said...

Thanks Olof. I've not looked at TTT data. I found a reference on this page, where it's stated that it's obtained by removing some of the stratosphere influence (TLS) from the mid-troposphere (TMT). Or that's what it looks like:

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.

Hopefully it won't be too long before there's a v4 of TLT. If I get some time later, I'll do some charts of TTT v4.

Olof R said...

Btw, RSS has a nice trend browse tool .
TTT v4 has a relatively high global trend, 0.174 C/decade, similar to the fastest warming surface datasets. In the tropics TTT v4 (0.189 C/decade) warms >30% faster than e.g. Hadcrut4, which proves the "elusive" tropical hotspot..

Tony Banton said...

I came to the defence of seaice1 and the stealey came in as the current pack-leader attack-dog.

Bellman said...

It's surprising how many comments there are saying that satellite data is unreliable, and that Spencer and Christy are not to be trusted because they are funded by the Government. How time change.

Mark B said...

I don't care much for Roy's predictions. Given his prediction for January, I can't see that they are based on the past or any particular understanding of ENSO events and the lower troposphere response.

In his previous post (3/31) Spencer discussed modeling of El Nino/La Nina. While his biases show in his writing and may potentially affect his data product, but I don't think he's completely abandoned science.

Sou said...

I've now added a chart with TTT data - just the 12 month average to March each year. It's more interactive than the HW normal fare :)

Olof R said...
This comment has been removed by the author.
Tadaaa said...

maybe its me getting old and soft - but that seemed one of the more "considered" threads on WUWT, not quite as hysterical as usual - and dbstealy aside the rational posters (thank you) were not really engaged

Harry Twinotter said...

My prediction is Dr Spencer or Dr Christy will be thrown under a bus by the deniers sooner or later. Look what happened to Dr Muller of Berkeley Earth.