I’ve mentioned before how chosen color schemes greatly influence how people see surface temperature data. Frank points out that sea surface temperature presentations suffer from the same problem. – Anthony
Guest post by Frank Lansner
This is no news – but still needs to be told. NOAA can in many contexts come up with the hottest temperatures available. Here we take a look at the European Sea Surface Temperatures as of 3 may 2010.
NOAA vs. UNISYS, SST, Europe. When I look at this compare, again and again I have to check if these SST are from the very same date, 3 may 2010. But they are. Differences are immense to an extend where it hardly makes sense to look after the European SST?
NOAA is hotter than UNISYS in for example these waters:
The Baltic Sea, The North Sea, The Caspian Sea,
And in addition,
The Black Sea has NOAA Approx. 3,5 K warmer than UNISYS, and
“The NOAA hotspot area” North of Scandinavia: NOAA Approx. 4 – 6 K warmer than UNISYS .
Is there a valid sound simple explanation for these great differences?
In addition NOAA uses a colour scheme that makes Europe look as if surrounded by burning lava. It’s quite a difference to the impression you get when looking at the UNISYS graphic.
So which graphic is correct? For the Baltic, here’s what the “jury” says, SMHI (From Sweden) has an updated SST for the Baltic Sea from exactly 3 may 2010:
The 3 graphics agree reasonably for the Northern Baltic Sea, but for the rest of the Baltic Sea, SMHI shows in average around – 1,5 degrees Celsius anomaly. Both UNISYS and NOAA show too warm temperatures, but NOAA far worse than UNISYS. So, NOAA is around 2 K warmer in this area than SMHI – the best estimate.
Europe is not the only area where NOAA has warmer temperatures than UNISYS. NOAA appears markedly warmer than UNISYS on the Northern Hemisphere – but a little colder than UNISYS in areas of the Southern Hemisphere:
http://weather.unisys.com/surface/sst_anom.html
Link to NOAA SST – use “FULL GLOBAL” to see all:
http://www.osdpd.noaa.gov/PSB/EPS/SST/climo.html
Link to SMHI detailed SST for Baltic + Danish waters:
http://www.smhi.se/polarview/
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Visit Frank’s blog: Hide the decline
Carrot eater, both datasets are from the Satellite years so your viewpoints about how these data could just explain 6 K in difference due to different years are nonsense to me, i’m sorry.
Look, call it “hand waving” or what you want, say that i don’t do my math because NOAA doesn’t show what exact satellite years they use or whatever.
I think most people can see a problem over Scandinavia, even though one set might not use exactly the same years between 1979 – today as the other:
http://hidethedecline.eu/media/SSTNOAAvsUNISYS/SST2010may3Europe.jpg
Over and out, Carrot Eater.
How map images are manipulated to make normal temperatures appear alarming. [source]
?????
It has been stated time and time again that we can expect a 1°C increase for a doubling of CO2 without feedbacks in our atmosphere based on the general acceptance of Fourier’s law. I do not have any problem understanding the concept of filling a sealed glass chamber with varied levels of different gases and comparing the various energy levels maintained by different gases in the sealed system at equilibrium due to varied input levels of outside radiation.
There is the control of the outside chamber’s reflective properties of the glass, there is the inside chamber’s reflective properties of the glass and there is the heat energy that is stored by the glass itself. As the chamber is the same, Fourier’s experiments show the different potentials for energy storage among gases(period).
QUESTION: (Not a rhetorical one)
How is it that we can apply Fourier’s law to earth’s atmosphere which is neither a sealed glass chamber nor at equilibrium regarding CO2?
If this were face to face I would stop there and eagerly wait for an explanation. However, I think that leaving the above honest question on a thread, some might think that in spite of my previous declaration I was presenting a rhetorical question. It is my understanding during the course of my readings that Dr. Lindzen and others have said things along the lines of Fourier’s law regarding the expected one degree Celsius increase in response to a doubling of CO2 in the absence of other forcings, and I just can’t wrap my head around it.
Somebody please explain to me the concepts that I am missing that are understood by people like Dr. Lindzen who say that we can expect a 1°C response to a doubling of CO2 in our atmosphere in the absence of equilibrium, a sealed environment & any other forcings?
Personally, I think the NOAA color scale is better. It is easy to see where has a positive anomaly and where has a negative anomaly.
The unisys color scale has blue/cyan color to represent positive anomalies which is unconventional and maybe a little bit misleading…
Frank,
“Carrot eater, both datasets are from the Satellite years ”
I have no idea how much that limits the possible differences at any given location, on any given day. Keep in mind that we’re looking at specific locations on (presumably) specific days. The variability in this is higher than in, say, studies of variability in the annual global mean.
Maybe there is some underlying difference in the data sets, or how they were processed. Maybe there’s some weird software glitch somewhere. After all, I have no idea where the numbers are coming from. But until you put the numbers on an equal footing, we can not begin to think about that.
I like this one from NOAA, along with Unisys. They white out the near average waters. It is weekly average, though.
http://www.esrl.noaa.gov/psd/map/images/sst/sst.anom.gif
That’s from here.
http://www.esrl.noaa.gov/psd/enso//enso.current.html
Paul says:
May 7, 2010 at 9:45 am
“QUESTION: (Not a rhetorical one)
How is it that we can apply Fourier’s law to earth’s atmosphere which is neither a sealed glass chamber nor at equilibrium regarding CO2?”
Short answer, you can apply the ‘law’, but the calculated results will be inexact.
There are many ‘laws’ of physics which require conditions to be applied which are not easily found in nature, and the answers will be incorrect. Because many climate processes are sensitive to initial condition, even slight errors multiply quickly and end up producing nonsense results.
“Maybe there is some underlying difference in the data sets, or how they were processed. Maybe there’s some weird software glitch somewhere. After all, I have no idea where the numbers are coming from. But until you put the numbers on an equal footing, we can not begin to think about that.”
Then you can agree that NOAA, UNISYS, SST maps are pretty much useless for anything.
personally I think NOAA ‘s color scale is trash. How many colors of red are there ?NOAA cooler colors are still yellow and green,Which I HATE Ithink UNISYS give most accurate reading.
Andy Krause says:
May 7, 2010 at 10:50 am
“Then you can agree that NOAA, UNISYS, SST maps are pretty much useless for anything.”
No, they’re potentially very useful, provided you know what is being shown. But this article is an attempt to use them, without knowing what is being shown. That’s the problem.
terry46 says:
May 7, 2010 at 10:55 am
“personally I think NOAA ‘s color scale is trash. How many colors of red are there ?NOAA cooler colors are still yellow and green,Which I HATE Ithink UNISYS give most accurate reading.”
Huh? The NOAA map above doesn’t even use green. Yellow is on the positive side, as would seem reasonable to me. Maybe you’re talking about a different graph?
It’s the infosys colorbar that’s a bit strange, if anything, with a shade of blue actually turning up on the positive side.
terry46 says:
Terry, there are no greens on the NOAA map for you to hate. What’s more, if you look closely you will see that yellow only represents warmer than the baseline–not cooler. It is one thing for to be sceptical about NOAA material but all this fuss about colour schemes has reached a new low for the sceptics and shows desperation.
Carot Eater: you write: “Keep in mind that we’re looking at specific locations on (presumably) specific days.”
If the base period was 1 day, 1 week or maybe 1 month one could image quite large anomalies, but we are normally talking about base periods of many years, often decades when NOAA make a base period. An area like the one North of Scandinavia cannot possible quite lokaly deviate with 6 K for many years and thereby give this NOAA hotspot North of scandinavia for years now. Its really just out of the question, no more no less. A little decimal deviation is possible.
And that NOAA makes the error and not show clearly the base period, does not mean that we cannot tell the obvious about their hotspot. Because an giraf stands on a mouse, we can still tell that the giraf has a long throat 🙂
Anyway, BRIAN D, found a similar NOAA SST graphic, with a baseperiod: 1982-96.
so far so good.
Frank:
A baseline may be listed as several years, but you have to also check what periods within those years are being used. For land surface data, if I’m going to find the anomaly for the month of May, I will subtract out the average of all Mays in my reference set; not the entire reference set.
That’s why I’m wondering how the daily anomaly is being calculated, because I have no idea. For May 3, are they subtracting the average of all May 3rds in the period 198x to 199y, or all days in May over that span, or all days in the first week of May? I don’t know, but it’s the sort of thing I’d want to know before I started working with these numbers. Looks like it’s discussed here: http://coralreefwatch.noaa.gov/satellite/methodology/methodology.html#ssta
Are you saying that exact same red spot north of Scandinavia is there every single day, over the course of several years? If so, that would be interesting to look at. But you’re only here showing one day.
But for your point about any apparent disconnect between the data sets: I’m sorry, but you simply have to put everything on the same basis first. If you are going to use a data set, you should first know what it is. Once you know what it is, then assuming you can download the data, then it’d be pretty simple to put it on the same basis for whichever part of the map you care about.
Failing that, you could download the data for a given grid box, in the three different data sets, and plot the trends over time. If the trends are parallel but simply offset from each other, then it was just a baseline issue. If not, then something else is up. Maybe the sets really do disagree, I have no idea. But you have to do more to show that.
You can say until you’re blue in the face that you don’t actually know the difference due to the baselines, but that you’re sure it’s small, but that just isn’t acceptable. If somebody is going to compare individual anomaly values from CRU and GISS, they must put them on an equal basis first. Same thing here.
You can’t compare two anomaly maps with different baselines- at least not in the way you’re doing it.
Look at it this way. Say the Noaa baseline is zero degrees. An area where the temp ranges from -0.25 to +0.25 degrees plots as part positive anomaly (+o.25) , part negative anomaly (-0.25).
Now say the unisys baseline is 1 degree. Those same temperatures would plot as anomalies of -1.25 and -0.75: all negative.
And it looks like NOAA uses a finer grid- so little hot spots on the NOAA map would be “averaged out” in the unisys map.
The temps north of sweden/norway seem different between the two (there’s a wider range of temps in the NOAA version)- maybe that has to do with different ways they handles sea ice?
But in the rest of the world, the two maps look pretty consistent to me.
“And it looks like NOAA uses a finer grid”
If so, that’s something to keep in mind.
“maybe that has to do with different ways they handles sea ice?”
If sea ice were an issue between the two sets, wouldn’t that show up over a larger area in the Arctic?
Pyromancer76 says:
May 7, 2010 at 6:40 am
I wish Leif would apologize to Frank.
I don’t think any is necessary [but if so, will gladly give one]. My small complaint was about the fuzziness in using ‘SST’ for what is ‘SST anomaly’. With different baselines, one gets maps that cannot be compared at a glance [which is what such maps were supposed to be useful for]. One can always by analysis of the numbers extract information from the maps, and Frank is correct that they don’t compute, but one should not have to do that. ‘At a glance’ is a powerful tool.
Tom,
“Why do different groups use different baselines?”
For good historical reasons. Anomalies are used basically to take out effects due to local siting. You need a reasonable time to estimate that – thirty years is conventional. You want to make sure that as many as possible of your sites have data in that period, so you choose the most recent thirty years. Well, almost – people also like to go for calendar decades.
Once chosen, you accumulate a whole lot of data and published plots expressed relative to that anomaly base. There’s a big cost in changing, and no reason. So it stays, for the same sort of reason the US sticks with F.
So GISS, which started Gistemp in the ’80’s, use 1951-80. CRU, which formalised in the ’90’s, use 1961-90. Satellite data people use a period since 1979, because that’s where they have data.
So, I’m really curious how one would resolve the discrepancy. Obviously the NOAA and UNISYS are using different software, as is the Swedish outfit. This could reasonably mean that they use different modelling algorithms. In such a case, how would one go about doing an apples-to-apples comparison?
Nick Stokes says:
May 6, 2010 at 11:45 pm
“The color scheme fussing is silly. My own area is computational fluid dynamics, and the NOAA style scheme has been standard for at least 30 years. It’s even there as one of the standard palettes (heat.colors) offered by R, a stats package which has nothing to do with climate science.
“Yes, it makes higher temperatures look hotter. It’s meant to. It communicates something to the reader.”
You neglected to tell us exactly what you thought it communicated (and was meant to communicate) to the reader. A dishonest distortion of reality intended to deceive the general public, no?
[A, I think the warmist trolls doth protest far too much on this post, and it shows that, far from what they are saying about us being desperate, it must really be of some significance to them in revealing yet more of the inherent dishonesty of their side of the AGW argument.]
Hi Carot eater, yes the hotspot is in fact a rather famous NOAA feature, i havent invented it,
Here January 2010:
http://www.osdpd.noaa.gov/data/sst/anomaly/2010/anomnight.1.18.2010.gif
July 2009:
http://www.osdpd.noaa.gov/data/sst/anomaly/2009/anomnight.7.9.2009.gif
Feb 2009:
http://www.osdpd.noaa.gov/data/sst/anomaly/2009/anomnight.2.9.2009.gif
Aug 2008:
http://www.osdpd.noaa.gov/data/sst/anomaly/2008/anomnight.9.11.2008.gif
April 2008:
http://www.osdpd.noaa.gov/data/sst/anomaly/2008/anomnight.4.10.2008.gif
nov 2007:
http://www.osdpd.noaa.gov/data/sst/anomaly/2007/anomnight.11.12.2007.gif
Mar 2007:
http://www.osdpd.noaa.gov/data/sst/anomaly/2007/anomnight.3.5.2007.gif
Apr 2006:
http://www.osdpd.noaa.gov/data/sst/anomaly/2006/anomnight.4.7.2006.gif
nov 2005:
http://www.osdpd.noaa.gov/data/sst/anomaly/2005/anomnight.11.18.2005.gif
feb 2004:
http://www.osdpd.noaa.gov/data/sst/anomaly/2004/anomnight.2.21.2004.gif
feb 2002:
http://www.osdpd.noaa.gov/data/sst/anomaly/2002/anomnight.2.8.2002.gif
apr 2000:
http://www.osdpd.noaa.gov/data/sst/anomaly/2000/anomnight.4.8.2000.gif
etc.
But, C.Eater, you are missing the point:
Its the BASE period that is many years long and there fore cannot hold a very local super heated area. You cant have for exampple the state of New York 6 degrees hotter than the neighboring states for many years, its just not possible.
Therefore, the POINT:
We are comparing UNISYS and NOAA. There is a huge difference for a nunmber of Sea areas between those two for the very same day. If this where due to different baselines, then the baselines over manye years on quite local areas should have deviated srtongly without neigboring areas affected. Its just not possible.
The baselines made over many years cannot explain huge temperature differences for local areas, mostly different baselines can explain differences on global scale or at least hemispherical. Not for instance the hot spot North of Scandinavia.
Or that is, yes, the baseline data can explain this is huge local difference if the baseline holds the error im looking for.
Hi Chris V!
you write:
“The temps north of sweden/norway seem different between the two (there’s a wider range of temps in the NOAA version)- maybe that has to do with different ways they handles sea ice?”
There has been no sea ice there since 1979, the sattelites, so i think not 🙂
And, yes, baseline is important, but important to explain global scale differences – or perhaps hemispherical. Certainly not those small specific areas i have pointed out as I explained to carot eater above.
K.R. Frank
Anu says:
May 7, 2010 at 6:42 am
“Hot is hot – I don’t think the color schemes really matter:
“…”
A novel form of hand-waving, for sure. You really are anxious to distract from the significance of this post, aren’t you?
“carrot eater says:
May 7, 2010 at 11:27 am
Andy Krause says:
May 7, 2010 at 10:50 am
“Then you can agree that NOAA, UNISYS, SST maps are pretty much useless for anything.”
No, they’re potentially very useful, provided you know what is being shown.”
– Exactly, to extremely different suggestions to what the SST anomaly is…
So if you want to know if its hot in Scandinavia you have to confront to datasets, then dig up some references not available etceetc.
No its a mess to have so big differences, it makes your impression completely random. You can just as well try to look in a crystal bowl.
Tenuc says:
May 7, 2010 at 10:29 am
Short answer, you can apply the ‘law’, but the calculated results will be inexact.
There are many ‘laws’ of physics which require conditions to be applied which are not easily found in nature, and the answers will be incorrect.
Tenuc, on this issue I tend towards your “and the answers will be incorrect” but because minds such as Lindzen state with what seems to me certainty it warps my mind to figure out how they reach these conclusions.
I’ll state my bias up front. I have been retired from Unisys for years, and at one time worked for several years on Univac/Unisys weather software contracts for the USAF. Some years prior to that I wrote weather software for the USAF as a Blue Suiter.
Unisys has been in the Weather Software business for decades and you can see much of the output on their weather website. As near as I can tell, the data to be plotted is pulled directly from standard weather communications circuits as common observational data.
I would expect Unisys to have no interest in warming or cooling, but only in selling software. I suspect that if Anthony has any questions about the massaging of data prior to or during plots, Unisys would probably gladly answer reasonable questions by phone, and be happy about the exposure.