Dear Mr. Burton,
In US data then as now, the adjustment that makes the biggest difference (because it is so systematic across US stations) is one to compensate
for the change in the time of day the maximum and minimum thermometers were read. Given the significance of this adjustment, Russ Vose, an NCDC
Climatologist, re-evaluated it a few years ago. His paper available here
ftp://ftp.ncdc.noaa.gov/pub/data/ushcn/v2/monthly/vose-etal2003.pdf
(now here: http://www1.ncdc.noaa.gov/pub/data/ushcn/papers/vose-etal2003.pdf -DAB 11/9/2013)
documents that re-evaluation and the impact on the network.
All of NCDC's adjustments of US data are in the USHCN network (which NASA uses a version of). The link: http://www.ncdc.noaa.gov/oa/climate/research/ushcn/ushcn.html has
documentation on adjustments, raw and adjusted data, for both USHCN v1 (in use in 1999) and USHCN v2 (the current version).
Data sets do change over time, particularly when one station closes and the creators have to select a different nearby station to use
instead. Also, the tradition at NCDC and indeed most homogeneity adjusted data sets around the world, is to adjust early data to make them homogeneous with
current observing practices, location and instrumentation. So if a station moves in 2005 to a new location that is 0.2 C colder (or warmer) than it was in
2004, then the data set creators would adjust that station's data in the 1930s (and all other data pre-2005) to be 0.2C colder (or warmer) as well.
As to the specifics of your questions, attached is a reprint from 2001 by several authors, including three from the National Climatic Data
Center (NCDC), and published in the Journal of Geophysical Research using USHCN Version 2 data. However the US graphs are not the same, and the data for
the US that Hansen used is the US Historical Climatology Network Version 1 (see below). For an explanation, the link to the USHCN Version 2 page is:
http://www.ncdc.noaa.gov/oa/climate/research/ushcn/
There are also references on that page that address the various temperature adjustments.
A description and data access for USHCN Version 1 can be found at: http://www.ncdc.noaa.gov/oa/climate/research/ushcn/ushcn.html
Additional information can be found beginning with the FTP directory at:
ftp://ftp.ncdc.noaa.gov/pub/data/ushcn/
I hope these references help answer your questions.
Sincerely,
Sam McCown
Customer Service Meteorologist
Phone: (828) 271-4800 ext 3174
Fax: (828) 271-4876
e-mail: {redacted}
National Climatic Data Center
151 Patton Ave, Rm 120
Asheville, NC 28801-5001
---------- Forwarded message ----------
From: ncdc.orders <ncdc.orders@noaa.gov>
Date: Wed, Feb 1, 2012 at 9:33 AM
Subject: sm*Fwd: Re: CSRRT Enquiry // Burton // US Surface T
To: Sam McCown
-------- Original Message --------
| Subject: |
Re: CSRRT Enquiry // Burton // US Surface T |
| Date: |
Wed, 1 Feb 2012 04:18:33 -0500 |
| From: |
David Burton |
| To: |
ncdc.orders@noaa.gov |
Dear NCDC Climate Services Branch climate contact,
I've been trying, without success, to learn how and why, over the last ~12 years, NASA GISS has
added approximately 0.7 C of increased 1930s-to-1990s warming in revisions to their old temperature records for the 48 contiguous United
States. I've also been trying, without success, to locate the unadjusted temperature data.
They say that they didn't make the adjustments, NCDC did!
It is very strikingly different from current NASA GISS graphs of the U.S. 48-state surface temperature record.
Compared to the 1999 version, recent versions show about 0.7 C of additional warming from the 1930s to the 1990s, comprised of a combination of increases
in post-1965 temperatures and decreases in pre-1965 temperatures (especially in the 1920s and 1930s).
I'm aware of a paper discussing 0.29 C of adjustments, but no explanation for the
rest.
0.7 C is a very large increase to come from late adjustments to old data! It is about
equal to the entire 20th century's global warming!
Nick Schor told me that that Reto Ruedy at NASA GISS told him the difference is not due to
adjustments made by NASA GISS, but rather due to adjustments made by NOAA NCDC "to accomodate siting and measuring biases," before NASA received the
data.
Based on the old version of the data, a page on nasa.gov said
(circa 2001), "it is clear that 1998 did not match the record warmth of 1934." But now NASA's data shows 1934 as only 3rd-warmest year,
and cooler than 1998. (This is all referring to U.S. 48-State temperatures, not global temperatures.) So what was "clear" to NASA in 2000
apparently is thought to be untrue, now.
I've stumped Prof. Scott Mandia of the Climate Science Rapid Response Team, and he
suggested that I contact you.
Can you please help me to:
2. find the the actual station lists and temperature and adjustment and weighting data used, for each of the stages of adjustment, and
3. understand the adjustments that were made, and why they should be trusted.
Thank you!
Sincerely yours,
Dave Burton
Expert Reviewer, IPCC AR5 WG1
Cary, NC
>
On Sun, Dec 25, 2011 at 12:27 PM, Scott Mandia {email address redacted} wrote:
David,
Your request is not really one that CSRRT typically responds to because you are not a journalist nor a
government official. I have tried to help but I can no longer continue this email thread. I suggest that you contact the NCDC
directloy to try to locate what you are looking for.
Regards,
============================================================
Scott A. Mandia, Professor of Physical Sciences, Asst.
Chair
T-202 Smithtown Sciences Bldg., S.C.C.C.
533 College Rd., Selden, NY 11784
Skype: agw.prof
"High Standards Inspire Superior Performance"
============================================================
From: David Burton
Sent: Sat 12/24/2011 12:51 PM
To: Scott Mandia
Cc: Michael C. B. Ashley; Jan W Dash; John P. Abraham; Dr. Reto Ruedy; Steve McIntyre; Anthony Watts
Subject: Re: CSRRT Enquiry // Burton // US Surface T
Dear Prof. Mandia,
I hope you're having a very merry Christmas holiday!
I see that Suffolk County CC has a break from 12/22/2011 through 12/26, so I presume you're taking a vacation from
climate work. Do you think, though, that you'll be able to take a stab at answering my questions when you get back (or pass them on
to someone else who might be able to find the old/unadjusted data, etc.)?
Warmest regards,
Dave
On Sun, Dec 18, 2011 at 7:01 PM, David Burton wrote:
Dear Prof. Mandia,
Thank you for your reply.
On Sun, Dec 18, 2011 at 8:23 AM, Scott Mandia wrote:
Thank you for this link. However, I don't find any quantitative information about the 48-State
temperature record & how it was adjusted there. There're no station lists, no weightings, no per-station data (let
alone per-station before-and-after-adjustment versions or per-station adjustments), not even a mention of the fact that
different adjustments were applied, both between 1999 and 2000, and between 2001 and present, in addition to the adjustments
made in 2000 which are noted in your 2001
paper.
It does say, "The NASA GISS Web site for the
global temperature data of Hansen et al. is the most comprehensive and direct source of information for these data."
However, I've already search that site in vain for unadjusted data and old (circa 1999) data. The
WaybackMachine web site only has archives for that site back to 2005:
I've downloaded the source code, and I'm an IT guy (Masters in CS), so I can probably figure it out, but
it'll take some time.
which is also very interesting, but it doesn't have much information about the specifics of the updates, and
has no information at all about the adjustments made prior to the changes described in your 2001 paper.
(It is mildly amusing but also disappointing to me that, despite all the discussion on that page of the 2007
correction to the "Y2K-ish" goof that Stephen McIntyre found, there's no thank-you or even mention of McIntyre on that
page!)
Here are the links to the various USHCN versions:
This is interesting, too. However, I don't see any raw data there, nor even the averaged, annualized
1999 version of the Fig.D, used to
create that 1999 graph(a).
Did I overlook it?
Digression: I'm a sea level guy, not a temperature guy, so there are a lot of holes in my knowledge
about temperature stats; please forgive my ignorance! But I noticed an interesting coincidence. NOAA's reported "optimum" grid (2.5 deg
x 3.5 deg) for temperature analysis is similar to another climate-related number. When I examined the correlation
between sea level trends at coastal tide stations vs. distance between the stations, I found only a slight correlation (other
than the global trend) at distances greater than ~400 km (~250 mi), which is just a little larger than the average distance
between grid lines on NOAA's "optimum" grid. Odd, eh?
Especially interesting on that page are the graphs showing the effects of several adjustments:
Eyeballing the 2nd graph, it appears to show the following 1930s vs 1990s adjustment effects:
TOBS (area adj & TOB adj): +0.34 F
MMTS (sensor change adj): + 0.04 F
SHAP (station history adj): +0.20 F
FILNET (missing data est): +0.02 F
FINAL (urban heat island adj): -0.06 F
----------------------
sum: +0.54 F = 0.30 C
(that's the same total as the adjustments described in your 2001 paper, or about half of the total
1999-to-present adjustments visible in the NASA graphs which Mr. Goddard compared)
(My eyeballed numbers are apparently off by about 4%; the page's
summation graph shows a total about +0.52 F adjustment to the 1990s as compared to the 1930s.)
One interesting -- and surprising, to me -- note was in the explanation of the SHAP adjustment, which adds ~0.2 F of
1030s-to-1990s warming, and for which the page says, "from 1950 to 1980... many
sites were relocated from city locations to airports and from roof tops to grassy areas. This often resulted in cooler
readings than were observed at the previous sites..."
That information is new to me. My impression was that the opposite effect was more common: gradual
urban encroachment would cause properly-sited grassy-area stations to become surrounded by buildings, parking lots, roads,
runways, etc.. Anthony Watts is obviously the leading expert on temperature station siting issues, so I'm going to cc
this email to him. Perhaps he'll weigh in.
This page is also interesting, if somewhat disconcerting.
The discussion of "Homogeneity Testing and Adjustment Procedures," makes me mildly queasy. The
statistical tests described there seem like an excellent approach to identifying candidate stations, which
might have been moved or been otherwise affected by site quality issues. But it seems to me that the
changes should have been verified manually, by contacting whoever runs the stations, and simply asking them
about any apparent discontinuities, and thus correcting the deficiencies in the station metadata, rather than "correcting"
for changes that might not have actually happened.
The use of satellite night-illumination data as a proxy for urban warming also seems crude, to me. We
have population counts by census tract, maps with roads and municipal boundaries, google maps views for counting buildings,
etc., not to mention the station metadata and surfacestations.org
reports for most stations.
It is too bad that, unlike the v1 page, this v2 page seems to have no quantitative information about the effects of the
various adjustments.
It is mildly amusing but also disappointing to me that, just as NASA avoided mentioning McIntylre while
discussing his work, this NOAA page manages to extensively discuss (and to some extent rebut) Anthony Watts' surfacestations.org project and its findings, without ever thanking him
and his team, or even mentioning him by name! There seems to be a rather petty "us vs. them" attitude in much of the
climate research community, rather than a spirit of cooperation in scientific discovery.
There's a lot of data here, but I don't see any U.S 48-state averages or graphs at all for v3.
It appears that none of these pages have the averaged, annualized 1999 version of the Fig.D used to create that 1999 (a) graph, nor any information
about the adjustments which were made between that 1999 version and the "unadjusted" version discussed in your 2001 paper,
nor even the station list and weighting/averaging process used.
My guess is that the equivalent of Fig.D used to be on either the NASA or NOAA web site, somewhere, but it
appears to have been at its current location only since about 2006 (at least this 2006
version is the oldest one archived by The WaybackMachine).
Can you please help me find these things?
I must admit that I do not understand your comment
"What was "clear" to NASA in 2001 apparently is known to
be untrue, now. That makes me wonder what might be clear to NASA today which will be found to be untrue in the
future."
Sorry, my mistake. It was 2000, not 2001. (The copy of the article I found was in a 2001
WaybackMachine archive, but the article itself was from 2000.)
A 1999 article by Drs. Hansen, Ruedy, et al, said, "in the U.S. the warmest decade was the 1930s and the warmest
year was 1934," and a longer article by Dr. Hansen in 2000 said, "it is clear that
1998 did not match the record warmth of 1934."
But now NASA says just the opposite: that 1998 was warmer than 1934.
So what was "clear" to NASA in 2000 has subsequently been found to be untrue, apparently as the result of the
accumulated adjustments/corrections which have been made to the data since 1999.
Analyses and data today are typically better than those
from earlier times. This is how science advances. Regardless of what happened in the 1930s in a small
region of the world (US), it is clear from many different data sources and techniques that the world is warming and
GHGs are the primary reason. Do not lose site of the forest because one tree has been made to look suspect by a
person (Goddard) who lacks skills and believes in global conspiracies.
Why do you keep attacking Goddard? Goddard's contrast of NASA's 48-state temperature graph produced in
1999 to the same graph produced recently was not the product of any lack of skills or belief in global conspiracies. It
is very interesting and informative! Had he not done that, I would not have even realized that recent adjustments to
the U.S. surface temperature record account for all of the reported warming when the 1990s are compared to the
1930s.
So I naturally wondered about the quality and reliability of those adjustments. (Wouldn't you? Don't
you?)
Step 1 to answering that big question is obviously to get hold of the unadjusted data, from which that 1999
graph was produced.
Step 2 is to examine the specific adjustments, weightings, etc., and try reproduce the adjustments and
thereby get the recent version of the graph from the old data, and make some determination about the reliability and
correctness of the adjustments.
Frankly, sea level work is a lot easier! Step 2 seems like wading into a great, big, mucky swamp.
So perhaps I should be grateful that I'm still stuck on step 1, unable even to find the data from which that 1999 graph was
produced.
There's a lot to wonder about this process!
For instance #1, I wonder about the gridded temperature data.
#1a, In addition to the grid section size and shape (2.5 deg x 3.5 deg), there's also the issue of how to
position the grid. If the grid is shifted east, west, north, and/or south by varying amounts, the result will be
different groupings of temperature stations, and presumably different results. Has anyone tested this, to see how much
variation in the results that causes?
#1b, I wonder how the weighting is done when the gridded temperature data is combined. Since the grid
sections vary in size (3.5 degrees being smaller in the north than in the south), when the temperature data is averaged, are
the grid sections weighted according to their size, or are they all weighted equally?
#1c, And what about partial grid sections (grid rectangles which overlap U.S. borders), how are they weighted?
Perhaps these details, or at least some of them, are in the downloaded computer code for the newer data, but
I've found no code at all and no data at all for the 1999 version, so I certainly can't compare the two!
Can you help me find the old code & data, please?
============================================================
Scott A. Mandia, Professor of
Physical Sciences, Asst. Chair
...
Warmest regards,
Dave Burton
Member, NC Sea Level Rise Risk Management Study Advisory Committee
Cary, NC
P.S. -- I've cc'd this to a couple of people whose names have come up in this conversation; I hope you don't
mind. Unfortunately, I don't have email addresses for Steven Goddard and Nick Schor, so I've not cc'd them.
On Sun, Dec 18, 2011 at 8:23 AM, Scott Mandia wrote:
David,
Here are the links to the various USHCN versions:
I must admit that I do not understand your comment "What was "clear" to NASA in 2001 apparently is known to be untrue, now. That makes me wonder
what might be clear to NASA today which will be found to be untrue in the future."
Analyses and data today are typically better than those from earlier
times. This is how science advances. Regardless of what happened in the 1930s in a small region of
the world (US), it is clear from many different data sources and techniques that the world is warming and GHGs
are the primary reason. Do not lose site of the forest because one tree has been made to look suspect by a
person (Goddard) who lacks skills and believes in global conspiracies.
Regards,
============================================================
Scott A. Mandia, Professor
of Physical Sciences, Asst. Chair
T-202 Smithtown Sciences Bldg., S.C.C.C.
533 College Rd., Selden, NY 11784
Skype: agw.prof
"High Standards Inspire Superior Performance"
============================================================
From: David Burton
Sent: Sat 12/17/2011 4:54 PM
To: Scott Mandia
Subject: Re: CSRRT Enquiry // Burton // US Surface T
Dear Prof. Mandia,
Than you for your reply.
The inquiry from Nick Schor to Dr. Ruedy was because of comments from me which Nick read
on-line, and my inquiry to CSRRT was at his suggestion.
However, I didn't ask about global temperatures, nor about the relative merits of
bloggers like Goddard and Tamino, nor about anyone's skills, competence, or motivations for good or
ill, nor about Dr. Muller & the ongoing B.E.S.T. study. (As an aside, however, I will say that I make
it a practice to read blogs on both sides of the climate debate, but not Tamino's; since he permits no
substantive dissent on his blog, I think that makes it pretty useless as a resource.)
(scaled to
match the graph below)
If you examine the two versions of the graph, and compare 1930s temperatures with 1990s
temperatures, you can see that the newer version adds about 0.7 C of warming!
I thank you for the link to your 2001 paper. It is interesting and informative, and the graphs on page 18 are
helpful. But, as you can see (e.g., compare the 1934 & 1998 peaks), the adjustments documented there
account for only ~0.3C (about half) of the warming adjustment added to the 1990s as compared to the 1930s:
(scaled to match
the graphs above)
If you compare the "unadjusted" (A)(a) graph from your 2001 paper to the 1999 version, you can see that there
is already a substantial difference (e.g., the 1934 peak is lower and the 1998 peak is higher in the 2001
version), and if you compare the adjusted versions (b) & (c) from your 2001 paper to the current version
there's another substantial difference (1934 is about the same but 1990 & 1998 are higher). Each of
those those changes also added to the indicated warming.
You know that they say, "the devil is in the details," so can you point me to the pre-2007
versions of Fig.D, and to the
actual station lists and temperature and adjustment and weighting data used, for each of the stages of
adjustment?
Also, do you know what accounts for the other ~0.4 C in adjustments which added to the reported warming?
Based, presumably, on the 1999 data, a 1999 article by Drs. Hansen, Ruedy, et al, said,
"in the U.S. the warmest decade
was the 1930s and the warmest year was 1934," and a longer article by Dr. Hansen in 2000
said, "it is clear that 1998 did not match the record warmth of 1934."
Obviously, they trusted that the unadjusted 1999 data was correct, when they wrote that.
But now NASA's data shows 1934 as only 3rd-warmest year, and cooler than 1998.
What was "clear" to NASA in 2001 apparently is known to be untrue, now. That makes me wonder what might
be clear to NASA today which will be found to be untrue in the future.
However, it is encouraging to read from Dr. Ruedy's message to Mr. Schor that these
changes by the NCDC were to account for "well-researched biases produced by documented station
moves and documented changes in the measuring protocols." That very documentation is
one of the two things I asked for.
The other thing I asked for was the uncorrected data, as graphed in the 1999 version of
the graph, above. The current ("adjusted USHCN") version of the annualized & averaged temperature
data is at http://data.giss.nasa.gov/gistemp/graphs/Fig.D.txt, but I can't find the earlier, unadjusted
versions. I'm very glad to read from you that
"all of that data is publicly available," and from Dr. Ruedy that
"NOAA/NCDC's USHCN data are still available, both the unadjusted and the various adjusted
versions," but call me a dunce, I just can't find it. Please help me out: where is that data,
including the unadjusted versions?
Can you tell me where to find these things?
Warmest regards,
Dave Burton
Cary, NC
On Fri, Dec 16, 2011 at 6:23 AM, Scott Mandia wrote:
Dave,
I am pasting below a reply from Reto Ruedy of NASA GISS who responded to a
similar inquiry this week. A few things to keep in mind:
1) The rise in global T has been observed by thermometers and satellite data
by several groups. All of these independent groups show a remarkably similar rising
trend. The latest effort to plot global land T by BEST (run by a climate skeptic, Dr. Richard
Mueller) also agreed.
2) Steven Goddard is mathematically challenged with regard to
statistics. Even Anthony Watts over at WUWT has stopped allowing him to post there.
Tamino over at Open Mind has routinely exposed Goddard's "mistakes". Search for Goddard at
http://tamino.wordpress.com/?s=goddard
3) What incentive would any scientist have to present false data,
especially when all of that data is publicly
available? Goddard's claims violate common sense and you should ignore people like him
who are wasting your valuable time and energy.
From Dr. Ruedy:
Nick,
My best guess
looking at the blogs you mention is that the basis for that accusation is that we used NOAA/NCDC's
GHCN (global historical climate network) data as our only source for the US up to 1999, then
- in year 2000 - replaced the US data by the adjusted USHCN data. These adjustments (made by the NOAA/NCDC group, not by NASA/GISS)
corrected for well-researched biases produced by documented station moves and documented changes in
the measuring protocols. The effect of this source switch on global temperatures was
statistically insignificant, however the US mean temperature series was affected
substantially.
NOAA/NCDC
recently redesigned the web documentation of their work, giving more emphasis on a newer procedure to
adjust the data. In particular a nice graph that showed the effect of each adjustment on the US
temperature series is no longer part of that display. But you still can find the corresponding graphs
in our paper
http://pubs.giss.nasa.gov/docs/2001/2001_Hansen_etal.pdf
Look at the
graphs (B) on page 18 and you'll see that most of the tilting is produced by the Time-of-Observation
debiasing and by the station history adjustments; both biases seem to have hidden some of the warming
that occurred.NOAA/NCDC's USHCN data are still
available, both the unadjusted and the various adjusted versions and those graphs can easily
be checked.
In summary:
“NASA/GISS tweaking†is really “NOAA/NCDC's
correcting of artificial biases based on careful studies of the available meta
dataâ€.
Sincerely,
Reto
Ruedy
============================================================
Scott A. Mandia, Professor of Physical
Sciences, Asst. Chair
T-202 Smithtown Sciences Bldg., S.C.C.C.
533 College Rd., Selden, NY 11784
Skype: agw.prof
"High Standards Inspire Superior Performance"
============================================================
From: Dave Burton
Sent: Thu 12/15/2011 8:11 PM
To: Scott Mandia; John Patrick Abraham; Michael Ashley; Jan W. Dash
Subject: CSRRT Enquiry
Name: Dave Burton
Email: {redacted}
Organization: Member, NC Sea Level Rise Risk Management Study Advisory Committee
Organization Description: The North Carolina Office of Geospatial and Technology Management
Floodplain Mapping Program (NCFMP) has a $5 million grant from FEMA to comprehensively study the
change in exposure and potential impacts to built and living systems, and to develop science-based
mitigation and adaptation strategies that will pro-actively reduce future impacts of sea level
change.
Response Needed By: n/a
Enquiry: I am interested in the data depicted in the graph labeled (a) in this 1999 NASA
article: http://webcitation.org/63wGUTWt6 It is very strikingly different from current NASA
GISS graphs of the U.S. 48-state surface temperature record. Compared to this 1999 version, recent
versions show about 0.7 C of additional warming from the 1930s to the 1990s, comprised of a
combination of increases in post-1965 temperatures and decreases in pre-1965 temperatures (especially
in the 1920s and 1930s). 0.7 C is a very large increase to come from late adjustments to old data! It
is about equal to the entire 20th century's global warming! I've been told by someone named (or
perhaps using the pseudonym) Nick Schor that Reto Ruedy at NASA GISS told him the difference is not
due to adjustments made by NASA GISS, but rather due to adjustments made by NOAA NCDC "to accomodate
siting and measuring biases," before NASA GISS received the data. Based on the old version of the
data, a page on nasa.gov said (circa 2001), "it is
clear that 1998 did not match the record warmth of 1934." But now NASA's data shows 1934 as only
3rd-warmest year, and cooler than 1998. What was "clear" to NASA in 2001 apparently isn't even
thought to be likely, now. This sort of inconsistency does not inspire confidence! A blogger who goes
by the pseudonym of "Steven Goddard" has a striking depiction of the difference, made by contrasting
1999 and 2011 NASA GISS graphs of the 48-state average surface temperatures, here:
http://stevengoddard.files.wordpress.com/2010/10/1998changesannotated.gif?w=500&h=355
I would like to know where to find the unadjusted data, used to create the 1999 graph (a) of the
48-state U.S. surface temperature record; i.e., the unadjusted (1999 and/or later) version of this
table: http://data.giss.nasa.gov/gistemp/graphs/Fig.D.txt I would also like to know where
I can find a complete (quantitative & qualitative!) explanation & justification of all the
adjustments which have been made, and who made them. Can you help me find these things? Thank
you!
|
