I’ve been following this issue a few days and looking at a number of stations and had planned to make a detailed post about my findings, but WUWT commenter Steven Douglas posted in comments about this curious change in GISS data recently, and it got picked up by Kate at SDA, which necessitated me commenting on it now. This goes back to the beginning days of surfacestations.org in June 2007 and the second station I surveyed.
Remember Orland? That nicely sited station with a long record?
Note the graph I put in place in June 2007 on that image.
Now look at the graph in a blink comparator showing Orland GISS data plotted in June 2007 and today:
NOTE: on some browsers, the blink may not start automatically – if so, click on the image above to see it
The blink comparator was originally by Steven Douglas. However he made a mistake in the “after” image which I have now corrected.What you see above is a graphical fit via bitmap alignment and scaling of the images to fit. This is why the dots and lines appear slightly smaller in the “after” image. I don’t have the GISS Orland data handy at the moment from 2007, but I did have the GISS station plots from Orland from that time and from the present, downloaded from the GISS website today. If I locate the prior Orland data, I’ll redo the blink comparator.
I believe this blink comparator representation accurately reflects the change in the Orland data, even is the dots and lines aren’t exactly the same thickness.
Douglas writes in his notice to me:
It appears that RAW station plots are no longer available, although NASA GISS (Hansen et al) do not say it in this way. Here is the notice on their site:
Note to prior users: We no longer include data adjusted by GHCN and have renamed the middle option (old name: prior to homogeneity adjustment).
I don’t know about the “renamed” option, but the RAW data appears to be NO LONGER AVAILABLE.
Here’s a detailed blink comparison of Orland. All their options now give you an “adjusted” plot of some kind. The “AFTER” in this graph show the “adjustments” to Orland.
Here is what the GISS data selector looks like now, yellow highlight mine, click to enlarge:
Above clip from: http://data.giss.nasa.gov/gistemp/station_data/
Here is the “raw” GISS data plot of Orland I saved back in 2007:
And here is another blink comparator of Orland raw -vs- homogenized data posted by surfacestations.org volunteer Mike McMillan on 12/29/2008:
And here is the “raw” GISS data for Orland today, please note the vertical scale is now different since the pre-1900 data has been removed, the GISS plotting software autoscales to the most appropriate range:
Source:
And it is not just Orland, I’m seeing this issue at other stations too.
For example Fairmont, CA another well sited station well isolated, and with a long record:
Here is Fairmont “raw” from 11/17/2007:
And here is Fairmont from GISS today:
Source:
This raises a number of questions. for example: Why is data truncated pre-1900? Why did the slope change? The change appears to have been fairly recent, within the last month. I tried to pinpoint it using the “wayback machine” but apparently because this page:
http://data.giss.nasa.gov/gistemp/station_data/
is forms based, the change in this phrase:
Note to prior users: We no longer include data adjusted by GHCN and have renamed the middle option (old name: prior to homogeneity adjustment).
Appears to span the entire “wayback machine” archive, even prior to 2007. If anyone has a screen cap of this page prior to the change or can help pinpoint the date of the change, please let me know.
It is important to note that the issue may not be with GISS, but upstream at GHCN data managed by NCDC/NOAA. Further investigation is needed to found out where the main change has occurred. It appears this is a system wide change.
The timing could not be worse for public confidence in climate data.
I’ll have more on this as we learn more about this data change.
UPDATE1 from comments:
GISS also just started using USHCN_V2 last month. See under “What’s New”:
http://data.giss.nasa.gov/gistemp/graphs/
“Nov. 14, 2009: USHCN_V2 is now used rather than the older version 1. The only visible effect is a slight increase of the US trend after year 2000 due to the fact that NOAA extended the TOBS and other adjustment to those years.
Sep. 11, 2009: NOAA NCDC provided an updated file on Sept. 9 of the GHCN data used in our analysis. The new file has increased data quality checks in the tropics. Beginning Sept. 11 the GISS analysis uses the new NOAA data set. ”
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Well OT but take a look at this one over at The Air Vent
Is it possible that the raw data is being withheld or is it gone—either trashed or manipulated to the point of being unrecognizable and useless?
REPLY: No it is still intact at NCDC, on paper forms, with transcription data also available – Anthony
From Clayton Cramer’s blog: Pasteurized Data
All this talk about how the CRU “homogenized” the data to remove inconsistencies brought forward a comment from a reader. He pointed out that the data wasn’t just homogenized; it was also pasteurized: heat was added until the data was completely sterile!
The “blink comparator” is the skeptics’ “nuclear option” for fighting revisionist temperature history.
Apparently the “global temperature record” is now also considered to be a “living document”.
This does not look good. Is there any other plausible explanation than just a NOAA and/or GISS sabotage of efforts to verify their temperature records ?
http://wattsupwiththat.com/2009/07/05/pielk-sr-responds-to-ncdcs-talking-points-about-surfacesations-org/
UDHCN1 did have some downward trend adjustments. But twice as many upward. The effect was to change the US station average (equally weighted) from +0.14C per century (raw) to +0.59C per century (full FILNET adjustment).
I’ve started doing some research on what sort of adjustments are done when the data is homogonized … mainly with Pennsylvania stations … so far about half the stations show a step ladder of adjustments … i.e. greater adjustments down in the early years 1900 ish stepping up to zero adjustments for the last decade …
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keep in mind these adjustments are down … if they were adjusting for UHI then we would expect the most recent adjustments to be the highest …
seems like a neat trick to get the slope to be steeper … don’t raise the near term temps, just lower the older temps …
Haha. Data not included.
tried to illustrate the stepladder … failed miserably …
You don’t teach an old monkey new “tricks”. Let’s not hide the decline. Just remove the negative slope by removing the data… that’ll do the “trick”.
Oh, and don’t forget to delete the emails too.
I did download the data on 09-12-09. But i downloaded data that was spliced together allready. So i don’t know anything with regard to this adjustment.
So disregard my previous statement.
Someone has lots of ‘splainin’ to do.
If you are looking for another ‘odd’ set of stations- check out Valencia and Castellon-Almazora in Spain. They are 30 miles apart and both about 2 miles from the Med. But Valencia is a big city and Castellon a much smaller town.
Three things- the unadjusted data are in close agreement up until about 1972, at which point they diverge by over a degree, with Valencia much warmer (urban effect?).
Secondly if you look at the adjusted data, they are suddenly in much closer agreement after 72- but it is Castellon that has been adjusted UP, not Valencia down.
Finally- if you look at Valencia by itself between 1900 and 1950, you will see that they have adjusted those temps downward a full degree across the board.
Now there may be very good reason for these adjustments (which obviously should be published- neither of the stations appear to have moved, at least according to the historical change db), but at first blush it would appear Valencia has an urban heat issue, and instead of correcting it NOAA instead corrected the nearest neighbor upwards to match. Moreover, a large adjustment to Valencia’s temps in the first half of the century have created (surprise) a hockey stick that doesn’t exist in its neighbor, and much less so even with the potential urban heating uptick.
(Also check out Alicante-Cuidad, the next town south, which also was adjusted way down in the 50s to produce a similar hockey stick. I’d really like to know why Valencia supposedly jumped a degree in temperature when none of her neighbors show this in their unadjusted data).
I like my temperature data the same way I like my sushi: Raw.
It has come to the point where we need to go back and dig up the paper records to be sure the information has been faithfully copied. Are images of station forms available? Or, has the paper conveniently dissolved?
Great work, Anthony. The self-referential nature of “climate science” as practiced by the AGW proponents (using tax money) is appalling. It appears that reality is being “adjusted” to fit the models, which of course, yield the desired outcomes. The individuals and organizations engaging in apparent data manipulation, data destruction and secrecy need to be held accountable.
“renamed” or just “reamed”.
We’ve been had.
An NOAA blink comparison: raw vs “adjusted” temperatures: click
[may take a few seconds to load]
Jeff (13:12:58) :
“”seems like a neat trick to get the slope to be steeper … don’t raise the near term temps, just lower the older temps …””
Are you getting a sense of the timeframe of a possible pivot point? In other words, is there a date in which many prior adjustments seem to be up and many later adjustments seem to be down?
Have we reached a point where to audit the basic data of this debate credibly we must return to paper records and carefully deliberate each of the needed adjustments in public; while at the same time reviewing the quality of those paper records from the standpoint of station maintenance and UHI effect? Are we at this point?
I wish I were retired already and had the time to begin such an undertaking.
Anthony,
Is there an archiving effort? We need snapshots of the evolution of the datasets over time if at all possible.
Also I have lost the URL to the PDFs of the paper forms. Can someone please post it? These need to get copied and secured in case they too disappear down the memory hole, or worse.
REPLY:
Station B91 PDFs here: http://www7.ncdc.noaa.gov/IPS/coop/coop.html
Transcribed here: http://cdo.ncdc.noaa.gov/dlyp/DLYP
Copenhagen climate change summit: The world is COOLING not warming says scientist Peter Taylor … and we’re not Prepared
http://www.dailymail.co.uk/sciencetech/article-1234515/Copenhagen-climate-change-summit-The-world-COOLING-warming-says-scientist-Peter-Taylor—prepared.html
To: Kevin Kilty (13:38:58) :
That’s what Anthony and Steve M. have been doing for a few years. Those are huge undertakings and we all owe them, big time.
Someone in Congress needs to make a big show of asking for full transparency of all data, code and adjustment explanations. After all, the science is settled. We just want to see what we paid for.
Anthony: watch this video…
[ http://www.youtube.com/watch?v=aUtzMBfDrpI ]
REPLY: Yes I’ve seen it. – A