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.
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:
Click for a larger image
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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?
![[Image]](http://discover.itsc.uah.edu/amsutemps/browse/AMSU_A_15.latest.a_04.png)
Click for larger image
![[Image]](http://discover.itsc.uah.edu/amsutemps/browse/AMSU_A_15.latest.d_04.png)
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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.
To Alan and others: similar “pauses” in the warming have been observed before: take the 79-85, the 86-95, the 90-96 periods and all you’ll get is an apparent cooling. Nevertheless, no-one in his (her) right mind would dare to say that temperatures decreased since 79, 96 or 90.
This is short-term variability opposed to long-term trends. By the way, take a look at the UAH tropospheric temperature data for January http://discover.itsc.uah.edu/amsutemps/amsutemps.html You can check that the temperatures we have rightnow are in no way “cooler” than what we had the previous years. Despite la nina. And the solar minimum.
Flanagan-
I’m just a lurker here but it seems that the issue is that the while the temperature has gone up very slightly there is also a great deal of disagreement about what that means. Is it catastophic or just normal? What is driving it? Does it require any action and is there any action that would be useful?
Besides that there is a great deal of question as to if the measurements are accurate much less significant. The science is not settled. http://www.drroyspencer.com/latest-global-temperatures/
Richard M (20:26:04) said: “steven G (20:03:56) makes a very good point about the 60 station nonsense. For a number like this to be valid it ASSUMEs a homogenized world. I don’t think many folks here believe our world is one giant climate. The truth is the world consists of multiple, interacting climates. Anyone who attempts to model the world otherwise is bound to fool themselves. ”
As a just a regular average Joe, it seems to me that this statement sums it all up. It has always been a mystery to me as to why we even try to get an average temperature of such a diverse and complex world. What does it really mean? At my locatoin we had lows in the upper 30’s this last few days but before that the lows were in the 50’s and 60’s which is where they are now. With such constant swings in temperature just at my location how can anyone even speak about 1.0 degree C average changes over the entire world? It makes no sense to me at all to even worry about it. And lastly, I never see any reference to the changes in the Earth’s obiquity or the precession of the equinox when discussing long term climate changes. As I have learned from Lief it is not TSI that counts it is solar isolation at the surface that counts and those two factors are the major players in determining that. As I understand it we are in a period of decreasing obiquity with the winter soltice heading for aphelion which should (in the long term) reglaciate the planet and there is nothing we can do about it. Luckily for us, our children, grandchildren and great grandchildren will not be around to suffer through that epoch.
But this is a most interesting blog and deserving of it’s award.
OT… Does anyone know where the most up to date sea level graph is? How often is it updated?
Has anyone ever been able to replicate GISS temp data?
When in doubt, go with the disclosed, most transparent data.
Hansen has stated in a public letter to Scientific American that he ahs managed his data to achieve desired results in the past.
I will be unsurprised if, as has achieved higher and higher status, that his ‘management’ of data is entirely jsutified.
crosspatch (20:28:35) :
“Ok – I’ll bite. Please tell me where these few dozens should be sited. ”
Ok, sure. If you are looking for a global trend over time, it isn’t really going to matter where you site them as long as you cite them away from places that have human causes changes such as land use changes. In theory, all you would need is one station because if the entire globe is warming, that one station should be enough to show that over a long enough period of time to cycle through all natural weather cycles.
C’mon CP, who is going to determine the cycle time of all natural weather cycles? A triffle ambigious, don’t you think? Or is 30 years enough? :<0
I would place them in locations far away from cities and far away from areas that are actively changing such as in the process of being deforested and the land use changed from, say, forest to farming. Areas that are static would be fine so an area that is currently farmed and probably will be the for next century or so would probably be just great. I might put stations in the middle of large national parks and wilderness areas. Also in places like desert and tundra would work, too. As would large areas of open space that is relatively static such as Northern Canada. I would place none of these stations near population centers. They would be intentionally difficult to reach and automated. They might be visited one or more times a year for calibration and maintenance but would be otherwise quite far from any human influence.
C’mon again, CP. Siberia is alledgely the farthest you can get from human influences, but look at the data we get from there. And what portion of this globe is entirely removed from human influences such as aerosols, soot, etc. IMHO, I agree with E.M. Smith, ie. global temps are globalogna. But then, I like warm.
The simplest answer is that GISS is affected by increasing UHI, erroneous adjustments, lack of coverage, etc, and satellites aren’t. The differences between the sets goes all the way back to the start of the sat temps (1979), with the differences increasing gradually since then. Not just GISS, but all the various surface temp records show this compared to the sat temps.
Just reporting the humanitarian views of of a real scientist.
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Obama’s Science Guy
http://www.boston.com/bostonglobe/editorial_opinion/oped/articles/2009/01/18/questions_for_obamas_science_guy/
John Holdren White House science adviser.
“He is also a doom-and-gloomer with a trail of erroneous apocalyptic forecasts dating back nearly 40 years – and a decided lack of tolerance for environmental opinions that conflict with his.”
Wrong Choice for White House Science Adviser
http://cei.org/cei_files/fm/active/1/William%20Yeatman%20-%20Holdren%20WebMemo.pdf
“…Holdren warned of “ecocide,” an “ecocastrophe” caused by expanding populations and growing economies that exceed the “finite ability of this planet to support people.”5 Holdren became a vocal proponent of population control.”
“In 2006, Holdren suggested that global sea levels could rise by 13 feet by the end of this century.”
“In 2007, Holdren said ”As droughts, heat waves, floods wildfires and severe storms intensify, damages to ecosystems and human society are growing apace.”
“Now Holdren is warning of “climate disruption,” (aka “global warming”) which he calls “the biggest environmental issue of our time, and indeed of any time.”16 He has been consistently wrong before, and he is wrong now. That and his cavalier disregard for human well being make him thoroughly unsuitable to be White House Science Adviser.”
E.M.Smith (01:12:47) :
jae (19:19:33)
6) Computer programs, although written in Fortran, almost unintelligible, and not subject to any known QA/QC programs, have been posted on the Internet for your perusal.
Where? (I was pretty good with FORTRAN once. it was my first computer language.)
I’d love to get a look at the guts for a little QA exercise. (Though if nausea is induced I’m bailing… 8-0
Might be able to get it over at CA but as far as I’m aware, no-one has been able to compile the source ‘as is’. Those that have been able to modify it to compile have been unable to reproduce the GISS figures.
Dave.
And here is the plot of the same three over another 72 month period, 1993 to 1999:
http://www.woodfortrees.org/plot/uah/from:1993/to:1999/plot/rss/from:1993/to:1999/plot/gistemp/from:1993/to:1999/plot/uah/from:1993/to:1999/trend/plot/rss/from:1993/to:1999/trend/plot/gistemp/from:1993/to:1999/trend
Both RSS and UAH show steeper warming than GISS, equivalent to the divergence discussed here but in the opposite direction.
And here is WFT’s own graph of these three plus Hadcrut over the whole satellite period, with baselines aligned:
http://www.woodfortrees.org/plot/hadcrut3vgl/from:1979/offset:-0.15/mean:12/plot/gistemp/from:1979/offset:-0.24/mean:12/plot/uah/mean:12/plot/rss/mean:12/plot/hadcrut3vgl/from:1979/offset:-0.15/trend/plot/gistemp/from:1979/offset:-0.24/trend/plot/uah/trend/plot/rss/trend
Which of the four is obviously divergent? Yup, it’s UAH. So, to quote Steven Goddard’s words above: ” In most scientific and engineering endeavours, the people in charge of the data respond to discrepancies like this with concern and thoughtful analysis.” What has been Christy & Spencer’s concerned and thoughtful response to this divergence? What, for that matter, is the response here? Any thoughts?
Steve Goddard, you wrote in your post, “Since the start of 2003, GISS has been diverging from RSS at 2.64C/century…”
Much of that can be explained as the difference between mediums sampled for the oceans, as noted in my 18:19:21 comment above. A quick extrapolation of the trend line in the first graph linked in my comment leads to a trend of approximately 2.02 deg C/century.
And as noted by looking at the long-term data, much of that is the difference between the responses of ocean TLT and SST to ENSO events.
Regards
What’s going on with the AMSU temperature http://discover.itsc.uah.edu/amsutemps/execute.csh?amsutemps ? Since Jan 08 it has been going up at a rate of approximately 0.1 def F per day.
Do you mean compared to last year? If so, one explanation might be that recent daily comparisons between 2008 & 2009 correspond to a particularly cold spell last year. But, even so Jan 2009 looks to be comfortably above average – and I stick by a prediction I made on another blog that 2009 will be warmer than 2008.
Yep, it’s a ghost of Solar Cycle 23 Past. It’s discussed over on the 95% sunspots thread.
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I think sat measurements are just more sensitive to trends. The surface network is too sparse now, as far as what is making up the dataset, and has siting issues that are less apt to pick up these trends, especially the cooling ones, as man’s influence on the network is strong, and is warm biased. I wouldn’t say we are comparing apples, and oranges, but certain apples are good baking apples, while many others are not.
It’s too bad are global surface network is in such bad shape. And if AGW were true, then sat measurements should be showing it with ease. Instead, it shows a strong natural signal with minimal human impact. Nature has warmed us much more than now, and I hope the trend continues. Because a cooling planet would be devastating to the human race. Civilizations have risen, and fallen because of natural climate change. It’ll happen again, whether we like it, or not. And, of course, be blamed on AGW. That’s man’s arrogance for you. It’s no wonder that “Pride” tops the list of sins.
Don’t get me wrong. I think being good stewards of the land, and sea are necessary. Diversity in energy resources, cleaning up pollution in the world, etc. are noble, and necessary. But some things cross the line, and AGW does just that. IMO
“To Alan and others: similar “pauses” in the warming have been observed before: take the 79-85, the 86-95, the 90-96 periods and all you’ll get is an apparent cooling. ”
Ric,
El Chicon and MT St Helen’s erruptions in ealry 1903s, and Mt Pinutumbo in the early 1990s explain much of the apparent cooling during those time periods; however, there doesn’t appear to be any short term cooling from 86-90. Not sure what your point is. Anthony picked 2003 to get away from the Super El Nino/ENSO cycle of 1997-2000. The point of this thread isn’t to cherry pick apparent cooling trends, but to point out a serious conflict in 2 datasets. Divergence points to a serious problem. As a matter of fact, the divergence problem MBH9X (the famed Hockey Stick) had sealed the reputation of Mann’s temp reconstruction. The last 30 years of Mann’s proxies diverged significantly with recorded local temps.
Hansen is attempting to do what Mann et als could not – call it building a Hockey Stick by other means.
Tim Clark
To get as far away as possible from human influences you need to go somewhere like…oh lets say Mauna Loa. The co2 record is apparently a direct reflection of the upward trend so the temperature records should be equally clear cut.
http://www.appinsys.com/GlobalWarming/RS_Hawaii.htm
Oh! Thats extraordinary… the vicinity of Mauna Loa doesn’t seem to have warmed at all since 1970. Halfway down the page someone has thoughtfully placed the temperature record over the co2 record. It doesnt fit. Nor in any of the national records I have tried this with over the years. The Keeling curve only seems to work with global temperatures.
tonyB
“C’mon again, CP. Siberia is alledgely the farthest you can get from human influences, but look at the data we get from there. And what portion of this globe is entirely removed from human influences such as aerosols, soot, etc. ”
There is potentially a serious UHI problem in Siberia, as Anthony posted awhile back. Above ground steam emmiting plumbing used to warm the cities during the most frigid periods of winter may be giving false warming -it all depends upon the siting of the temperature equipment.
The other problem is, of course, lack of reporting stations. GISS interpolates the temps for the empty gridcells there.
Ric (06:47:25) :
You point is interesting but does not supply any information. I would ask you simply why do we get these pauses in warming in the past?
Without an answer to that then looking at climate historically has no value for current conditions, this is especially true if you subscribed to AGW Theory. It pre-determines that the atmospheric composition that we have experienced since the beginning of the record has never existed in the recent historical records, so we have no frame of reference in the “recent” past and the distant past is unknowable at the level of detail we are using.
All we can do is look at the variations and effects of past factors in an attempt to quantify current ones, then extrapolate from here. This debate is really over who has the best guess.
Steven Talbot,
1993 to 1999 is not an analogy, because the trends were parallel (no divergence) through 1997, and then the satellites had a step function upwards in 1998 due to a very strong El Nino event which made a large spike in the data.
The 2003-2008 trend is different in that the divergence is linear and there were no major El Nino, volcanic or statistical events during the period.
Chart of projected CO2 & temp vs actual: click
[chart courtesy of leebert]
Indeed Climate Heretic,
You are on to the point of the Captain Andrew story. Unless temperature right now is recorded and, you, me, the moderators, the scientists who can’t agree on it, the politicians who won’t agree on it, everyone who ever cared or will care in the future and everyone agrees that’s what it is, and it is considered THE temperature today and no one ever changes it, because it is the history, does any of this have any meaning now or in the future.
Andrew ♫
A question. NOAA is the source of data for GISS. NOAA is a taxpayer funded organization. Is it not possible to:
(a) form a nonprofit group,
(b) request all of the NOAA data for all past years and all stations (even if having to do so via the FOI Act),
(c) write an independent code set (not using Hansen’s code base) and
(d) publish the results independently?
That would be a cross check on GISS, correct? I would think there are enough independent retired scientists, statisticians, and “open source” coders out there that could do the job within 18 months. All it would take would be a small number of well known people to kick this concept off.
Is this a foolish idea or not?
“global temps are globalogna. ”
I would tend to agree with that. And there is also a larger problem. We have been attempting to spot trends over too short of time spans. In the Northern Hemisphere, we seen to have a PDO cycle of about 60 years or so. It is looking to me like we get something like 30 years of cooling and 30 years of warming. What I think needs doing is looking at temperatures over several cycles. For example, the cycle that peaked in the 1990’s apparently didn’t get as warm as the cycle that peaked in the 1930’s. It also looks like we still haven’t hit as warm a cycle as we saw in the MWP. The MWP apparently wasn’t as warm as the Roman Warm Period. It looks to me that while we have periods of warming and cooling, each warming hasn’t seemed to reach as warm as the one previous so we have possibly been in a period of general cooling for the past thousand or two years.
I have a problem with people looking at rates of cooling over a decade or two and extrapolating that rate out over a century in the future when we are probably in only a 30 year cycle. Same with cooling. Superimposed on these cycles appear to be “super cycles” of things such as the Little Ice Age. We haven’t been keeping temperature records long enough (since the thermometer as we know it was invented only in the 1700’s.) to make intelligent projections 100 years into the future because we don’t know what normal behaviors are over periods of several centuries.
Looking at the warming from about 1976 on to about the early 2000’s, it was probably a mistake to project that warming to continue on for a century into the future and now we see the other half of the cycle coming into play as we appear to be in a period of cooling as we also experienced after the period of warming in the 1930’s during the 1950;s, 1960s, and early 1970’s. It would be equally wrong to project the current cooling for 100 years into the future as that probably isn’t going to happen either.
We need to look at where these cycles peak. Did this cycle peak at a higher temperature than the last one? If so, by how much? We need to watch this cooling period and see if it bottoms out lower than the one of the 1970’s. This is the only way we are going to see real trends in temperatures because temperature change isn’t linear.
Heck, we should record the temp is as many locations as possible as often as possible and never change them.
Andrew ♫
Anthony, could you put an e-mail on this site in order to send you information directly, without leaving them in comments?
For the lack of e-mail… please take a look at this: http://www.americanthinker.com/blog/2009/01/global_warming_is_for_dummies.html
After “Global Warming for Idiots”, now they will publish the “Global Warming for Dummies” and of course it is all over the Canadian Broadcasting Corporation up here.
Also, Have you heard of this German ship that left South Africa last week in order to dump tons of Iron Sulfide in the ocean to seed the ocean to boost the algea growth… against international laws???!!!
http://www.thetimes.co.za/PrintEdition/Article.aspx?id=915801
Reply: Take a look here. ~ charles the moderator
The more we glean temperature and record it and the more we never change it… that is the “better” we are looking for.
Andrew ♫