Is Spencer Hiding the Increase? We Report, You Decide
by Roy W. Spencer, Ph. D.
One of the great things about the internet is people can post anything they want, no matter how stupid, and lots of people who are incapable of critical thought will simply accept it.
I’m getting emails from people who have read blog postings accusing me of “hiding the increase” in global temperatures when I posted our most recent (Dec. 2009) global temperature update. In addition to the usual monthly temperature anomalies on the graph, for many months I have also been plotting a smoothed version, with a running 13 month average. The purpose of such smoothing is to better reveal longer-term variations, which is how “global warming” is manifested.
But on the latest update, I switched from 13 months to a running 25 month average instead. It is this last change which has led to accusations that I am hiding the increase in global temperatures. Well, here’s a plot with both running averages in addition to the monthly data. I’ll let you decide whether I have been hiding anything:
Note how the new 25-month smoother minimizes the warm 1998 temperature spike, which is the main reason why I switched to the longer averaging time. If anything, this ‘hides the decline’ since 1998…something I feared I would be accused of for sure after I posted the December update.
But just the opposite has happened, with accusations I have hidden the increase. Go figure.
To Nanuuq’s question about why he should accept that it’s been warming due to natural reasons: Yes, difficult to accept. But there is evidence: The warming trend started in 1850.
The massive emissions of CO2 due to a lot of industrialization only started in 1950. So there was already a lot of warming (with some cooling periods intermingled) BEFORE we increased the CO2 content significantly. This is a strong indicator for natural warming and cooling even if we cannot exactly explain the mechanism at the moment. Svensmark and Kirkby are trying to find out whether fluctuations in cosmic rays are the reason (via influencing cloud cover).
To Joel Shore: Hi Joel! I was just having fun and wanted to stir the debate up. In five years we can argue again, my bet is the cooling becomes more significant.
To be a little more specific Channel 5 reads the middle Troposhere and through mathematics they figure out a Lower Troposhpere Temp. Channel 9 reads the Lower Stratosphere a completely different layer of the atmoshpere. This can be found on WUWT in an older article by Dr. Spencer or on his own site at:
http://www.drroyspencer.com/2010/01/how-the-uah-global-temperatures-are-produced/
The only problem with moving to the longer 25 month moving average is that the data for 2009/2010 are delayed for a year. So, if Spencer expects the coming year to be very warm, then he is hiding (or delaying) the increase. As several have suggested in this posting, the best solution is to plot both the 13 and 25 month moving averages.
[Just a brief reminder: The monthly data is there on the same graph for all to see. RT – Mod]
MartinGAtkins (03:32:56) :
nanuuq (20:34:25) :
“i just want to know.”
Assuming his plea is genuine, then he has taken first step on the road to learning. He is probably young, so perhaps a little understanding is called for
Martin, I’m assuming that you didn’t read the thread. I have a rule with people who act like trolls. I give them a good enough answer and see what they do with it. nanuuq ignored mine and others and just kept up this infantile refrain. That’s when anything goes for me. Even at that, nanuuq would in fact benefit from Beck’s book.
The great thing about the internet is that anyone can download the meta-data and do thier own analysis. Why rely on Anthony, Steve McIntyre, Willis, NOAA, CRU, or GISS. With open source anyone with the desire to find the truth can do it themselves. With that in mind, cries of “hiding the decline”, or “hiding the increase” are somewhat hallow. As Anthony says many times to people here, “Do the math yourself.”
Once again, I’d like to draw attention that even within these comments we can see there is an element who refuse on principle to believe there’s been any warming. This isn’t skepticism, this is just playing tommy opposite.
Roy quite clearly believes there’s been warming, but that natural events are the main player.
The big issue for skeptics is: will it continue, and can we/should we do anything about it.
One should always be inclined to decline – it is politic.
Thanks for trying to answer Christopher, but I don’t think that answers why the apparent step change in the UAH satellite data. I agree there is not a correlation between carbon dioxide rise and temperature rise evident.
The “incline” is obvious… Just look between 1995 and 2000. That’s where the entire “incline” resides!
UAH
I appreciate Dr. Spencer diligent work, and his ability to be critical of HIMSELF!
However, I have a minor complaint here. If I take the zero line, and then lay out the data as a plus/minus variation on that line, I will obtain something akin to a “normal distribution” curve. Then I have a “standard deviation”.
Then I can plot a band of 3 SD’s and see if the data is trending beyond that.
If it is NOT then from a statistics basis WE CANNOT SAY THERE IS A SIGNIFICANT CHANGE.
Why can no one see this?
Excellent article Dr. Spencer. I really don’t see what increase either 13 or 25 month smoothing hides. As such it’s clear that you’re hiding nothing either way with your analysis as it’s just a rolling average with either a 25 month or 13 month range. One could use any range one wants to I suppose.
Besides wasn’t the “hide the decline” in the Hockey Stick Graphs/Analysis as confirmed in the Climategate emails pointing to selectively deleted “dead tree ring entrails” data chopped off the graph and the tail end lifted up to the thermometer data line? That’s hiding data by removing it. A smoothing doesn’t hide data, and certainly doesn’t hide anything when the data is presented along with it! It just shows an abstract mathematically smoothed line; which is a lot different than deleting data and “manNipulating” it with arbitrary values to enable “hockey stick soothsaying of whatever was wanted to fit the AGW Hypothesis”.
I’m curious what information is gleaned from the selection of different durations though from the perspective of climate science. What do the smoothing lines suggest to a climate scientist? I’d like to know more and if you could detail more about that I’d appreciate it.
In addition, as a computer and systems scientist I’d like to know more about the reasoning of using various statistical methods in “climate science” as many different methods are used and there seems to be much debate on their use and how appropriate they are for various purposes.
Might I ask what software you use to generate the graph? What is the specific data source? What are your equations (in detail please)? How can someone verify your computations if they so choose to?
pwl, dedicated to open source science where verifiable and auditable evidence rules the day
http://PathsToKnowledge.net
thanks for the info dudes
so it dont seem too bad
maybe its just the sun changing?
Not having done the math, I ask here.
I find myself wondering what happens as you extend the running average beyond 25 months to much longer periods… the smoothing line would tend towards becoming a straight line that would coincide with the trend line, wouldn’t it?
If that is the case the trend lines shown in various climate graphs can all be accused of “hiding” or “distorting the raw” data, yes? The point is what is the use of each statistical technique and is that use clearly spelled out so that a full audit can be carried out, isn’t it?
Honest science would spell out the exact steps just like is taught in high school science and math classes. Show the work is being honest.
That is why the Hockey Stick Graph work by Mann et. al. is so infuriating, they didn’t’ show their work – and it has taken a massive effort to get them to show their work – which included “deleting valid” data that in fact seems to have contradicted their AGW Hypothesis to the point of falsifying the correlation between “dead tree ring entrails” and thermometer temperature data readings.
In my view trust in climate science can only be reestablished via open source science with all the work steps shown publicly available for auditing.
pwl, dedicated to open source science where verifiable and auditable evidence rules the day
http://PathsToKnowledge.net
This may have been addressed, but since satellite measures the LT which is far removed from the surface, how can it be possible to compare anything but the trend?
For instance, the baseline difference between HadCRUT and UAH is .146. Many graphs use this anomaly based measurement to infer there is good agreement between the two and many I’d assume think there is a correlative relationship between the two products.
Yet, the absolute temperature bears no resemblance between the LT and the surface, so how can it be said anything other than the trend is similar?
If as E.M. Smith and others are saying is true, that being the GHCN is warming the present while cooling the past resulting in a large warm bias for the last 20-30 years compared to the 20’s through the 40’s, how is it that satellite and surface records for the last 30 years are considered “similar” in absolute terms?
Aren’t we talking apples and oranges here? In other words, if satellites were available 70 years ago, would it show the same change in absolute temperatures as the surface? What is the theoretical difference in temperature between the LT and the surface?
To me, to say satellite and surface data is similar using what appears to be a baseline calculation based on a corrupted surface station baseline (removing cold stations for the last ~20 years) is completely meaningless.
What am I missing?
E.M.Smith (03:15:43) : Thanks for your comments. I trade stocks rarely but do have an idea about so-called technical analysis. I have a chart of multiple moving averages 5,10,15 day short term (green colour) and 30,40,50 day longer term (red colour). The trends show clearly with the green on top in a rising market and the red on top in a falling market. The cross overs are useful for buy sell decisions. I have another chart as you indicate for the high and low peak trends giving tram lines for selling at or near the top line and buying at or near the bottom. I made something like the latter chart for rainfall to clearly identify wet and dry periods. In our area it clearly shows no change in the pattern over 100years ie no rise or decline. It was very wet in the 1890’s, severe drought 1900 to 1912, which has been replicated to a lesser extent 1998 to 2009. The rainfall pattern has been linked to ENSO. One would expect higher day temperatures in drought times because of less cloud cover but this could be offset by lower night temperatures. Average temperatures particularly global temperatures provide no useful information for farmers and graziers.
I would suggest to magicjava (19:54:39) : that he split day and night temperatures and look for some diversion
nanuuq (06:54:04) :
well, dude, are you just joking with all the ‘dude’ lingo?
Mark T (23:36:24) :
Smoothing on any time scale is perfectly legitimate.
This is not universally true. It depends upon what you are doing and why.
my point is that people are took what a troll said about 25 months and made it an issue.
Joel Shore (16:18:53), if the argument was only over the radiative effect of Co2 this blog wouldn’t exist. Most here agree with a ~1C temperature increase per doubling of Co2 which would mostly be beneficial. Warm is good, cold is bad. Living in Rochester I suspect you’d much rather experience that 80F summer day then just about any cold winter day.
It’s the feedbacks that are in question.
@John Hooper (05:13:27)
Maybe it will continue. Maybe it won’t. NO-ONE can say. And that ‘no-one’ certainly includes “scientists” using grossly simplified computer models based on cherry picked and distorted data and using algorithms that have been conconcted specifically to ‘prove’ the basic AGW hypothesis.
And even more so, the ‘no-one’ includes scientifically illiterate and dishonest NGOs, media and politicians who want to scare people into making donations, sell more newspapers and / or hugely raise taxes whilst grandstanding that they are ‘saving the world’.
The big issue for the AGW True Believers is: in the face of the fact that the climate “Just Keeps on Doin’ Whatta Climate’s Gotta Do”, can you justify pouring trillions of dollars into ‘solutions’ which are extremely likely to destroy the economies of the developed world and deny hope to millions in abject poverty in the third world?
Especially when evaluating the proposed ‘remedies’ for the alleged ‘problem’, not on the basis of “avoiding tonnes of CO2 emissions” but on the basis of avoiding temperature rise (EVEN BASED ON THE IPCC’s OWN “SCENARIOS”), these enormously costly and risky remedies will have no measurable benefit whatever!
This is the question that the Trolls must answer! It isn’t posters and commenters here who allege we only have X months to save the planet!
Sordnay:
Thanks for the link to the AWG “Believer” website. I spent about 15 minutes on it.
I immediately came back to WUWT. The contrast is stark.
The “Believer” website is pure EMOTIONAL content. No objective information.
It is so STARK to look at in comparison to WUWT.
WUWT readers will benefit by noting the contrast.
Max
Ref – nanuuq (19:55:57) :
“So like, i’m new to this, and only a couple of you have been of any help thanks D. Patterson, but it will take me a bit to read that stuff tho none of you really answered my questsions.
I’m sorry i’m not smart enough for you guys :(”
___________________
Many, if not most, of us are “new” to this. Read and re-read what you see here. Wiki-or-Google around the web and do more reading, and check out the links these folks give out too. Ask questions. Be careful not to jump on something that you’re not sure what it is; don’t drive over anything you’re not sure what it is. No one here is against you. Feel free to contribute. Be aware that these people genuinely want real answers too and not yesterday’s MSM propaganda. I was (and still am) also trounced a few times. The cuts heal.
PS: There ARE some primadonas with softskin, and some really old geezers that can’t read so well and need a little more empathy (like me), and you will appreciate their personalities better as time goes by:-) G’day!
The only way any smoothed series could hide anything would be if the monthly series was not also shown.
Dotto (00:54:40) :
Looking at the UAH data (http://discover.itsc.uah.edu/amsutemps/) I find that the lower atmosphere at 4,4 km (ch05), is extremely hot while the upper part at 17 km (ch09) is extremely cold now compared to the 20 year averages.
Does somebody have any theory on what is going on?
At 17km cooling is due to loss of ozone which causes heating at that altitude and increased CO2 which will give some radiational cooling there.
What is the weighting for the great spike of 1998, for the non-satellite product?
“Roy quite clearly believes there’s been warming, but that natural events are the main player.
The big issue for skeptics is: will it continue, and can we/should we do anything about it”
I will go one farther and say most sceptics believe the globe has been warming for about 300 years (since the coldest decades of the LIA). But it is quite another thing to declare the 1990s-2009 was the warmest period of the last 2 millenia.
What is so fascinating about the global weather since August of 2009 is the extremes we’re seeing. September was one of the warmest Septembers of the last 100 year; followed by one of the coldest Octobers of the last 100 years, which in turn was followed by one of the warmest Novembers. And the NH December was one of the coldest in 30 years.
One of the Hallmarks of the LIA was the erractic climate/weather patterns that circled the globe. At least at the onset, weather extremes seemd to dictate things. China saw both devastating droughts and floods; Periods of both droughts and high level glacier expansion marked the tropics; Northwest Europe saw about every kind of weather one could imagine. East Asia saw extreme cold and drought, which forced the Mongol armies to march westward, and the Franz Joesf Glacier in New Zealand saw rapid growth.
I think the Alarmists got it wrong; weather extremes seem to accompany a cooling planet, and not a warming one.
At least those of us in the NH can count ourselves lucky that this last 8 weeks was during an El Nino period, and not La Nina. One could hardly imagine how cold things would have gotten if the negative AO and NAO were buttressed by La Nina.