GISS Divergence with satellite temperatures since the start of 2003

By Steve Goddard and Anthony Watts

Some of the excellent readers of the last piece we posted on WUWT gave me an idea, which we are following up on here.  The exercise here is to compare GISS and satellite data (UAH and RSS) since the start of 2003, and then propose one possible source of divergence between the GISS and satellite data.  The reason that the start of 2003 was chosen, is because satellite data shows a rapid decline in temperatures starting then, and GISS data does not.  The only exception to the downward trend was an El Nino at the start of 2007, which caused a short but steep spike.  Remembering back a couple of years, Dr. Hansen had in fact suggested that El Nino might turn into a “Super El Nino” which would cause 2007 to be the “hottest year ever.”

The last six years (2003-2008) show a steep temperature drop in the satellite record, which is not present in the GISS data.   Prior to 2003, the three trends were all close enough to be considered reasonably consistent, but over the last six years is when a large divergence has become very apparent both visually and mathematically.

Click link for larger source image http://www.woodfortrees.org

Since the beginning of 2003, RSS has been dropping at 3.60C/century, UAH has been dropping at 2.84C/century, and GISS has been dropping at 0.96C/century.  All calculations are done in a Google Spreadsheet here:

The divergence between GISS and RSS is shown below.  Since the start of 2003, GISS has been diverging from RSS at 2.64C/century, and GISS has been diverging from UAH at 1.87C/century.  RSS has been diverging from UAH at minus 0.76C/century, indicating that RSS temperatures have been falling a little faster than UAH over the last six years, as can also be seen in the graph above.

Below is a 250km map of GISS trends from 2003-2008.  One thing which stands out is that GISS has large areas with sparse or no coverage.  Notably in Africa, Antarctica, Greenland, Canada, Brazil, and a few other places.

Click for larger image

Many of the GISS holes seem to be in blue regions on the map. Here is a post and video of the GHCN station loss over the past several years globally, created by WUWT contributor John Goetz:

Here are two images showing the difference between GISS global coverage in 1978 and 2008:

April 1978 anomalies

Click for a larger image

April 2008 anomaly

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There is a tremendous amount of station dropout in 30 years. Dropout is worst in the high northern latitudes, most all of Canada, and about half of Africa. Of particular note is the red band at the southernmost latitude, which “seems” to indicate a continuous coverage there. Of course we know that is not true, given the paucity of stations in the Antarctic interior. Read more here.

By contrast, while it doesn’t hit both poles (neither does GISS) UAH has much broader global coverage as seen below. Could this be part of the explanation for the divergence between GISS and satellite data?  What do the readers think?

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How different would the GISS graph appear, if it showed a -3.6C/century cooling trend over the last six years?  For reference, the steep GISS warming trend from 1980 to 2002 was about 0.4 degrees.

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DJ

[snip – no more posts from you until you apologize for the last one on the other thread. – Anthony]

BarryW

How does the divergence look when you compare latitude bands or by continents? That would allow you to look at station dropouts on a regional basis to see if that was correlated.

Lars Kamél

Since there is a weather station at the Amundsen-Scott base right at the South Pole, GISS should actually cover this pole. The northernmost and still operational weather station, on the other hand, is probably located at about 82N, quite far from the pole.
The Hadley/CRU temperature data set probably also diverges from GISS, since it show world mean temperatures dropping the last couples of years at almost the same rate as the satellite data sets.
REPLY: I had thought about Amundsen-Scott base, but the the red band seemed so large in area, compared to other stations, that it seemed unrealistic to treat it as a single station. Perhaps one station is being distorted in the map resentation. Mercator projection does that. – Anthony

Jim Norvell

There was this graph at Icecap. http://icecap.us/images/uploads/Stationdropout.jpg
What would it take to plot the temperature history prior to 1990 using only the post 1990 site data’?
Jim N

braddles

How is it that they have trend data for 2003-2008 for many areas that are blank in the 2008 map (e.g. northern Canada)?
Also be aware that the use of this type of map projection is quite misleading, making the polar regions look massively larger and more important than they really are.

Steven Goddard

DJ,
The spreadsheet linked in the article shows the standard deviation for the GISS minus RSS plot = 0.09. The trend line for the graph shows 1.6 standard deviations, across the six year period. Reasonably good statistical significance.
If you want to make any further calculations, please feel free to make your own copy the spreadsheet, and report back any findings you feel are important. That would be a constructive way to get involved in the conversation.
Thank you very much

stan jones

Well the thing that stands out like a sore thumb on the first GISS chart is the anomalous warming right across Russia. If that bright red spot on eastern Svalbard happens to be another Russian weather station reporting rather than a Norwegian one, I would be even more suspicious.

I hadn’t realised just how sparse GISS coverage is. Your graphic is truly GRAPHIC on this point. Why would anyone prefer it to HADCRUT. It’s time GISS either invested some serious money on increasing coverage or gave up.

DJA

The color scales are weighted to warming.
There are 5 colours of positive anomalies in the range 0.2 to 8.2, but only four colours of negative anomalies in the range -0.2 to -8.3. There is an extra white colour on the negative side which is the range -0.2 to -0.5.
So the world map is distorted towards the positive side.
Just how many of those white areas should in fact be blue?

TP

Speaking as a person with only a high school stats background, I wonder – how many data sets are necessary to validate which (if any) temperature record is the outlyer?
For example in my world (aviation), we use GPS extensively, but only if we have data from 5 or more satellites. With that many discrete signals, the software in the GPS receiver looks at each set of sat data, and can accurately identify and discard a single bad signal. My question, then, is this – are 4 separate temperature records enough to identify one of them as spurious, to a high level of confidence?

Steven Goddard

One thing that strikes me as odd is that the GISS map from April has more gray area than the trend map (which must include April.)
Do the stations sometimes appear and disappear? If so, how can they be included in the trend data?

gary plyler

On a more serious note, I plotted RSS, GISS, and UAH average annual temperatures from 1979 to 2008 inclusive. The linear trends of the three indicate that RSS and GISS agree fairly well and that it is UAH that is not rising as fast. I was personally disipointed that I could not share the plot with you (I am not that computer savvey) but I used Excell on the raw monthly data (a spreadsheet I worked out last week).
I would imagine that woodfortrees can show nearly the same result. Here is the woodfortrees plot (with GISS offset -.24 so all three are about equal at near 1990)
http://www.woodfortrees.org/plot/uah/last:360/trend/plot/gistemp/last:360/trend/offset:-.24/plot/rss/last:360/trend

just Cait

I am so happy you’ve done this, Anthony and Steve. I’ve been wondering about this but am mathematically challenged. Kudos to you both! Between the fudging of the figures and temperature station dropout, there’s a lot to answer for from Hansen et al.
Hansen seems to think Obama is a one term President since he believes Obama must make the necessary steps towards economic ruin within his first term. I think the President-elect needs to see this… and quickly before he does great harm to the country.

John Philip

But you just told us that This 1980-2008 discrepancy between GISS and UAH is important, as it is nearly equal to the claimed warming trend since 1980. , now it is Prior to 2003, the three trends were all close enough to be considered reasonably consistent, but over the last six years is when a large divergence has become very apparent both visually and mathematically.
Extrapolating, will the next post be on how GISS has diverged from the satellite record since Christmas? 😉
Seriously, as I pointed out earlier, the satellite record is more sensitive to ENSO events,and this seems to me a more plausible explanation is that the chart is than any changes in coverage, to repeat myself there was a similar divergence of the opposite sign leading up to the 1998 El Nino, shown clearly in this here chart from a post by Eli that shows pretty conclusively how GISS-RSS delta peaked during the 1998 El Nino, so it seems more sensible approach to look to the recent La Nina as a leading cause of this, so far, short-lived divergence in the other direction.
Perhaps a regression analysis of the ENSO index vs the divergence would be instructive?
Bye for Now,
JP

John Philip

Slightly more coherent version:
But you just told us that This 1980-2008 discrepancy between GISS and UAH is important, as it is nearly equal to the claimed warming trend since 1980. , now it is Prior to 2003, the three trends were all close enough to be considered reasonably consistent, but over the last six years is when a large divergence has become very apparent both visually and mathematically.
Extrapolating, will the next post be on how GISS has diverged from the satellite record since Christmas? 😉
Seriously, as I pointed out earlier, the satellite record is more sensitive to ENSO events,and it seems to me a more plausible explanation than any changes in coverage, to repeat myself there was a similar divergence of the opposite sign leading up to the 1998 El Nino, shown clearly in this chart chart from a post by Eli that shows pretty conclusively how GISS-RSS delta peaked during the 1998 El Nino, so it seems more sensible approach to look to the recent La Nina as a leading cause of this, so far, short-lived divergence in the other direction.
Perhaps a regression analysis of the ENSO index vs the divergence would be instructive?
Bye for Now,
JP

John Philip

Slightly more coherent version with working link. Blimey.
But you just told us that This 1980-2008 discrepancy between GISS and UAH is important, as it is nearly equal to the claimed warming trend since 1980. , now it is Prior to 2003, the three trends were all close enough to be considered reasonably consistent, but over the last six years is when a large divergence has become very apparent both visually and mathematically.
Extrapolating, will the next post be on how GISS has diverged from the satellite record since Christmas? 😉
Seriously, as I pointed out earlier, the satellite record is more sensitive to ENSO events,and it seems to me a more plausible explanation than any changes in coverage, to repeat myself there was a similar divergence of the opposite sign leading up to the 1998 El Nino, shown clearly in this chart from a post by Eli that shows pretty conclusively how GISS-RSS delta peaked during the 1998 El Nino, so it seems more sensible approach to look to the recent La Nina as a leading cause of this, so far, short-lived divergence in the other direction.
Perhaps a regression analysis of the ENSO index vs the divergence would be instructive?
Bye for Now,
JP

gary plyler (14:16:30) : “On a more serious note, I plotted RSS, GISS, and UAH average annual temperatures from 1979 to 2008 inclusive.”
Sorry, that manipulation doesn’t work for me. Straight line fits over a long interval remove information that clearly shows in unsmoothed data. The topic here is recent trends; using the 1979 ff data is an OT red herring.

“Below is a 250km map of GISS trends from 2003-2008. One thing which stands out is that GISS has large areas with sparse or no coverage. Notably in Africa, Antarctica, Greenland, Canada, Brazil, and a few other places.”
-No, one thing that stands out is the dismal coverage of oceans, more than two thirds of earths surface. Africa is bad but the ocean coverage is worse.

Steven Goddard

Gary,
It is interesting that RSS tracked GISS closely through 2002, and has started diverging over the last six years, as explained here. Do you have any ideas what might be causing that?

crosspatch

“It’s time GISS either invested some serious money on increasing coverage or gave up.”
GISS doesn’t set coverage criteria. They get their input data from NOAA. It would be up to NOAA to look into why so many stations are falling out of the network.
But you will notice that the stations fall out of the network in “steps” and there is no step change in the differences which means that the cause of the divergence is likely to be something other than the missing stations … such as their “adjustment” scheme.

Steven Talbot

Steven Goddard,
Do please try to figure out the basic and very obvious fact that the lower troposphere temperatures respond more to ENSO variations than does the surface composite, This was just as obvious in the opposite direction in 1998, Honestly, you could not give more sustained evidence of confirmation bias than you are doing. This is just entirely ridiculous and,frankly, reduces the ‘sceptic’ case to a matter of desperate data mining. Try to approach this with a scientific state of mind, rather than setting out to ‘prove’ your prejudices! Is it really the case that the ‘best science blog’ is running analyses of this kind, without the most basic suggestion of understanding what is being analysed?
REPLY: I grow rather tired of someone telling me what sort of analyses this blog should and should not do, particularly from someone who uses two different names. The idea of this blog is to explore things that interest me, the contributors, and the readers. This divergence interests us, and if it leads to a better understanding, then that is what we shall do. Often times people pointing out weaknesses or alternate ideas are the best way to learn, and I welcome pointing out mistakes or suggestions for other ways to analyse the data, sans the sort of snark you display.
Perhaps you are right, perhaps you are not, but, have you anything to illustrate your point about the GISS surface and ocean record being more sensitive to ENSO, other than an ad hominem taunt? If so, show it. Let’s discuss it and learn about it. – Anthony Watts

Steven Goddard

JP,
I don’t think the last six years have been marked by any particularly strong ENSO events, other than Dr. Hansen’s mention of the possibility of a “Super El Nino.” It is difficult to see how ENSO could be causing the divergence with RSS.
Now that Dr. Hansen has forecast that 2009 may be the “warmest year ever” due to his expectations of an El Nino, we will have to pay particularly close attention to the divergence in the coming months, as it is likely to get much larger.

evanjones

Hmm. But wasn’t the drop in temperatures for 2007/early 2008 even greater for GISS than for UAH or RSS?
The radical departure does not come until mid-2008. Moreso than at any other point in the graph.

Mark

What is the reason for all of those stations dropping out?

Steven Goddard

Steven Talbot,
Suppose that we do get a strong El Nino as Dr. Hansen has forecast for this year. Using your “satellites are more sensitive to ENSO” theory, we should see a huge swing in the GISS minus RSS numbers from positive to negative (as in 1998.)
Keep your eye out for that!

Garacka

Jim Norvell (13:39:47) :
“What would it take to plot the temperature history prior to 1990 using only the post 1990 site data’?”
I’d love to see that done. As it stands, we don’t have apples to apples coverage of land area before and after the mass extinction event in 1990. I think the problem is that Hanson would have to do it, because he hasn’t (??) provided the code to allow anyone else to replicate his machinations. I’d also like to see the “rural” only data run through the Global “averager” program.

kim

Steven Talbot (15:25:27)
Always useful to compare different tools. Jobs vary; use of tools does too. Sneering from partial understanding is a poor tool of persuasion for most jobs.
================================================

evanjones

The surface temperature measurers will have credibility problems so long as ANY PART of their procedures are not COMPLETELY out in the open for independent review and replication. Until that happens, surface temperatures will remain in serious question.
Until that happens, this New Yorker hails from Missouri: Show me.
It is especially baffling, considering NOAA and GISS are run by public servants, and therefore proprietary issues would not seem to apply.

Steven Goddard

One more comment about the ENSO theory. The GISS minus RSS divergence since 2003 has been fairly linear, through several ENSO positive and ENSO negative cycles. If the ENSO theory was correct, we would have seen large up and down swings and changes in polarity of the GISS minus RSS numbers, not a linear trend.
Based on this, I think the ENSO amplification theory is nullified.

Bill Illis

Actually, it is only GISS temps that doesn’t respond as much to the ENSO. Hadcrut3 has nearly the same response as the satellite temps.
NCDC doesn’t have as much response to the ENSO (like GISS) but the NCDC dataset has much, much less noise/variation in it so it is easier to see the impact of the ENSO.
I think GISS just has more noise in its data and they are trying to focus more on the high latitude polar regions (where there is more variation) and they are sacrificing the tropics region data (where there is more response to the ENSO).
The result is that GISS has more error in it and then less response to the La Ninas of 2007 and 2008.

peat

Assuming both temperature records are accurate, how can CO2 be the cause of recent warming trends? Since CO2 is distributed throughout the atmosphere, if it is responsible for excess heat, then shouldn’t the atmosphere warm first, followed by the surface? The 2nd law of thermodynamics is pretty fundamental (heat flows from hot to cold, not the other way around). Am I missing something?

Garacka

If troposphere responds more quickly to El Nino/La Nina events, is that the same as saying they respond more quickly to PDO changes?
If that is true than could the divergence be due to the recent 200X PDO switch to negative phase driving troposphere faster than surface temps? Give it a few more years for the effects of the negative PDO to ripple through the full atmosphere and the divergence will be gone (??)

The following comment was made earlier;
“Below is a 250km map of GISS trends from 2003-2008. One thing which stands out is that GISS has large areas with sparse or no coverage. Notably in Africa, Antarctica, Greenland, Canada, Brazil, and a few other places.”
reply
“-No, one thing that stands out is the dismal coverage of oceans, more than two thirds of earths surface. Africa is bad but the ocean coverage is worse.”
This raises the interesting question as to which- if any- of the land surface types the ocean most resembles with regards to its temperature characteristics? A desert-featureless? Mountains-turbulence? None at all? If so, as 70% of the earth therefore isn’t being measured at all, which only leaves the remaining 30% (which in itself only has 30% coverage) do ‘global’ temperatures have any meaning whatsover?
TonyB

John Philip

Based on this, I think the ENSO amplification theory is nullified.
You think so? Here’s a bit of fun –
(a) download the ENSO multivariate index from here http://www.cdc.noaa.gov/people/klaus.wolter/MEI/mei.html
(b) Calculate a monthly time series of (UAH-GISS).
Scale to fit and plot a and b on the same graph. Add a 12 month moving average to smooth the trend.
By eyeball it looks to me like there are periods of fairly good correlation with the temp data lagging the ENSO by about 6 months,I’ve put a quick and dirty representation of 1990 onwards here
http://spreadsheets.google.com/pub?key=pFFm87cBy5_o44oFXNuojPA
I’m busy right now, but may have a go at a correlation coefficient tomorrow, but first impressions are that ENSO is a bit of a prime suspect for at least some of the short term ‘divergence’, which would fit with the physical explanation that I’ve been banging on about …..

I posted this on the original thread, then realized it should probably be posted here: click

old construction worker

Steven Goddard (15:46:35) :
‘Based on this, I think the ENSO amplification theory is nullified.’
Oh no, not another amplification theory!!!! Isn’t that what got us into this CO2 drives the climate thing?

tty

Mark (15:41:33) :
Many of the stations haven’t dropped out, it is simply that NOAA does not collect data from them any longer. A ten minute search on the web will locate up-to-date (and historical) data for a lot of those missing stations from the websites of the meteorological agencies of e. g. Canada, Sweden, Norway, Denmark, Australia etc. etc.
As for why NOAA doesn’t bother to use the data, your guess is as good as mine.

Steven Goddard

JP,
This article is about the divergence since 2003. There have been several positive and negative ENSO events during that period, yet the divergence trend has been linear and monotonic, as seen above.
ENSO can not explain the divergence since 2003. If it were were correct, we would have seen a large negative swing (GISS minus RSS) in early 2007 – which we didn’t.

janama

I see no reason for the data from Australia to be less – we have automatic stations all over the country – we didn’t just recently shut any of them down.
REPLY: That is correct, and Australia, IMHO, has a better sited and maintained network than that of the USA. – Anthony

MartinGAtkins

stan jones (13:50:23)
If that bright red spot on eastern Svalbard happens to be another Russian weather station reporting rather than a Norwegian one, I would be even more suspicious.
Here is a SST anomaly map made up from multiple inputs. Svalbard has had that warm area for over a year. Volcanic?
http://polar.ncep.noaa.gov/sst/ophi/color_anomaly_NPS_ophi0.png

It’s worse than it looks Models have shown that the satellite trend should be 1.2 times greater than surface trend here’s a quote from John Christy (UAH) on CA.
J Christy:
December 19th, 2008 at 11:27 pm
Ratio factor:

Climate models display a fairly robust ratio of the troposphere anomalies/trends represented by the surface variation vs. the LT profile of MSU temperatures of 1:1.2 globally, and 1:1.3 in the tropics (Steve: it is 1.3 for the tropics and 1.2 for the globe). These have been called amplification factors. Models indicate that anomalies and trends of the surface become larger by these factors in the LT profile (See CCSP report for example or Douglass et al. 2007 for model results). Observations have not agreed with these model-calculated ratios for long-term trends, but do agree on monthly scale anomalies. (see Christy et al. 2007 on Tropical Tropospheric Temps) and Douglass et al. 2007.

It’s really an interesting quote.
The standard deviation of detrended satellite and ground data confirms his remarks. If correct, the divergence is substantially worse than we see.

Steven Hill

WOW, nobody really knows if the earth is hotter or cooler in the end…crisis is an opportunity for change! It’s all about the re-distribution of money, that I do know.

crosspatch

Mark (15:41:33) :
What is the reason for all of those stations dropping out?

The world wonders. It is a question that has been asked and has remained unanswered for years.

Roy

Just wanted to raise an issue for general awareness: if someone has been adjusting published government data with the intent to influence government action, that person could be prosecuted for violation of 18 USC section 1519 and be sent to jail for up to 20 years.
Given the severe implications that some proposed (and some enacted) legislative schemes could have on the economy and the general welfare of the United States and the entire world, folks who have confidence in their command of the data may be able to have a real impact on the public debate by calling the frauds to account and taking them to task on the data.
Even if not acted on (federal prosecutors having a great deal of discretion), the simple threat of jail for doctoring records or even manipulating data inputs with the intent to deceive decisionmakers might provide some “forcing” to prevent them from reaching a “tipping point.”
Thoughts?

John Finn

Has anyone checked the Hadley trend since 2003. I get -2.53 deg/century so it appears to be more in agreement with UAH/RSS than GISS (using Excel LINEST) – but I’ve had a couple of drinks so a ‘second opinion’ might be advisable.
John Philip (16:13:47) :
Based on this, I think the ENSO amplification theory is nullified.
You think so? Here’s a bit of fun –

JP
For reasons given above I’m not looking at numbers now, but following your argument you seem to be saying that Satellite readings are warmer (relatively) than the surface during El Nino events and cooler during La Nina. Since 2002, though, we have had largely ENSO-positive conditions which, according to the “ENSO amplication theory”, means that UAH and RSS should be warmer relative to GISS – so the trends should converge rather than diverge (up to mid-2007 at least). But I do need a clear head to think it through.

JP

Here is what could be done; subtract those gridcells that have less than 2 station coverage from the GISS database and re-calculate the the GISS temps from there. Will they divergence continue or lessen? If it does lessen, by how much? I have thought for a number of years that NASA has taken liberties with the sparsely populated areas of the globe. Most of thier large warm anomalies occur in these gridcells.

John Finn

In my previous post I appear to have invented a new word, i.e. “amplication” as in “ENSO amplication theory” . That should be “amplification”.

Being a curious cuss, I started wondering when the actual divergence started. It had to have been prior to 2003, since the RSS and UAH trends were already negative by 2003 while GISTEMP was still positive. I also wondered about the HADCRUT trend. So … if one adds HADCRUT to the mix and plugs in the year 2000 to WFT, the results show all four data set trends being still positive, although the slope for all data sets except GISTEMP is very close to flat. I’ll provide links for those who don’t want to spend the time working through the site:
http://www.woodfortrees.org/plot/uah/from:2000/plot/rss/from:2000/plot/gistemp/from:2000/plot/uah/from:2000/trend/plot/rss/from:2000/trend/plot/gistemp/from:2000/trend/plot/hadcrut3vgl/from:2000/plot/hadcrut3vgl/from:2000/trend
However, if one uses year 2000.1, the results change somewhat – at this point the RSS slope becomes negative while UAH and HADCRUT are nearly flat but still positive.
If one then uses year 2000.2, the results are somewhat different – HADCRUT is dead flat and RSS and UAH are negative.
http://www.woodfortrees.org/plot/uah/from:2000.2/plot/rss/from:2000.2/plot/gistemp/from:2000.2/plot/uah/from:2000.2/trend/plot/rss/from:2000.2/trend/plot/gistemp/from:2000.2/trend/plot/hadcrut3vgl/from:2000.2/plot/hadcrut3vgl/from:2000.2/trend
GISTEMP finally goes flat somewhere between 2000.9 and 2001. The WFT site is apparently not sensitive to less than a singe decimal.
http://www.woodfortrees.org/plot/uah/from:2000.9/plot/rss/from:2000.9/plot/gistemp/from:2000.9/plot/uah/from:2000.9/trend/plot/rss/from:2000.9/trend/plot/gistemp/from:2000.9/trend/plot/hadcrut3vgl/from:2000.9/plot/hadcrut3vgl/from:2000.9/trend
Using 2001 and 2002, of course, illustrate the increasingly negative slope for all data sets.
http://www.woodfortrees.org/plot/uah/from:2002/plot/rss/from:2002/plot/gistemp/from:2002/plot/uah/from:2002/trend/plot/rss/from:2002/trend/plot/gistemp/from:2002/trend/plot/hadcrut3vgl/from:2002/plot/hadcrut3vgl/from:2002/trend
And by 2003, we’re back where we started. Except that I also added HADCRUT to the mix:
http://www.woodfortrees.org/plot/uah/from:2003/plot/rss/from:2003/plot/gistemp/from:2003/plot/uah/from:2003/trend/plot/rss/from:2003/trend/plot/gistemp/from:2003/trend/plot/hadcrut3vgl/from:2003/plot/hadcrut3vgl/from:2003/trend/plot/none
I did NOT apply offsets or any other adjustments to the data sets.
I am, however, curious as to why it’s so hard for GISS and Hadley to understand and accept their own data. Basically 9 years of, at worst (or best), no warming and an increasingly negative temperature trend. Keep your longhandles handy.

Joel Shore

avfuktning med kontrollerad ventilation vind – vindsavfuktare says:

No, one thing that stands out is the dismal coverage of oceans, more than two thirds of earths surface. Africa is bad but the ocean coverage is worse.

Yeah…That does kind of stand out doesn’t it? It did to me too. So, I followed the link that was provided above and found out why: Anthony and Steve have chosen “none” for the ocean analysis. I.e., they are not showing the data that GISS combines with their own land surface temperatures to get the GISS global Land – Ocean temperature anomaly that they have been discussing. If you go to the site and make a plot again with the ocean analysis chosen as HadI/Reyn_v2, you will see that the ocean coverage is in fact quite complete except very near Antarctica and in the arctic.

Joel Shore

Jim Owen says

I am, however, curious as to why it’s so hard for GISS and Hadley to understand and accept their own data. Basically 9 years of, at worst (or best), no warming and an increasingly negative temperature trend. Keep your longhandles handy.

Maybe because they understand the huge errorbars in trends computed over such short time periods…And, they can see that one also sees this large variability in trends in the climate models forced by CO2 over similarly short time periods: http://www.realclimate.org/index.php/archives/2008/05/what-the-ipcc-models-really-say/
In other words, they understand the limitations in drawing conclusions from their data better than you do.