Open Mind

Before and After

August 12th, 2007 · 41 Comments

The global-warming-denialist blogosphere is aflutter. News of the recent correction to USHCN temperature data has caused them to declare that global warming no longer exists, that 1998 or 2005 is no longer the hottest year on record (it’s now 1934), and that global warming is a “Y2K bug.” For example, budsimmons gleefully asks, “Lets see if Al Gore revises his road show.”

The recently-discovered corrections apply only to some stations in the U.S., and the claim that “1934 is now the hottest year on record” applies only to the lower 48 states of the continental U.S. Before the recent correction, for the lower-48 U.S. states the years 1998 and 1934 were too close to call — a “statistical tie” — with 1998 having the slightly higher numerical value. After the recent correction, for the lower-48 U.S. states the years 1998 and 1934 are too close to call — a “statistical tie” — with 1934 having the slightly higher numerical value.

Yet most denialist bloggers simply state that 1934 is now the hottest year on record — with no qualification given that this applies to the lower-48 U.S. states, not to the globe. The lower-48 of the U.S. make up less than 2% of the area of the globe. What is the impact on global average temperature? What’s the hottest year on record — globally — after the correction? Let’s take a look.


GISS has already updated their downloadable data to reflect the recently-discovered correction. Let’s plot the global average temperature, using the data before the correction is applied, and after. Plotting the “before” numbers in red and the “after” numbers as open black diamonds, we get:

befaft.jpg

Hmmm… It’s rather difficult to see the difference. That’s because the difference caused by this correction is so small.

I’ve often referred to the period from 1975 to the present as the “modern global warming era.” Maybe we can see the difference more easily if we focus on that time interval:

from1975.jpg

The difference is visible — just barely — but clearly, it’s very small. Very small. Globally, 1934 is not the hottest year on record, not even close. Not even close; the ten hottest years on record have all occured since 1990. And #1 is still 2005 (according to GISS) or 1998 (according to HadCRU; it’s really a “statistical tie”).

The fact that the denialists are making such a big noise about such a small change tells us a lot about the weakness of their case. The fact that they trumpet 1934 as the “hottest year on record,” usually conveniently neglecting to mention that it’s for the lower-48 U.S. states rather than the globe, tells us even more.

UPDATE UPDATE UPDATE

A curious commenter asks:

I am still curious as to how this correction compares with the satellite data for the US now. Do the two data sets match up more closely or do they diverge?

Satellites estimate atmospheric temperature in several of the atmosphere’s layers; the estimates of near-surface temperature are the “TLT” channel (”lower-troposphere,” the lower part of the lower layer of the atmosphere). Using surface temperature data from NASA GISS, and satellite measurements from Remote Sensing Systems, we can compare annual average temperature during the satellite-observation era (1979 to the present). For the global temperature, we get this comparison:

global.jpg

The two series have a different zero point, because the “reference period” for computing anomalies is different for the two data sets. But they show the same ups and downs (although the satellite data show a stronger response to the 1998 el Nino), and the same trend (0.017 deg.C/yr for NASA GISS, 0.018 deg.C/yr for satellite TLT).

Likewise, we can compare measurements for just the lower 48 states of the U.S.:

usa48.jpg

Again, the zero point is different, but the ups and downs match, and the trends are nearly identical (0.030 deg.C/yr for NASA GISS, 0.029 deg.C/yr for satellite TLT).

UPDATE#2 UPDATE#2 UPDATE#2

It occured to me that I could make the comparision between NASA GISS surface temperature analysis and satellite measurements easier, by plotting the two data sets on separate y-axes. Of course, one must be careful that the two y-axes are the same size even though they’re offset to a different zero point. By doing so, we can cancel out most of the difference in zero-point between the two data sets. Rather than being very fussy in an attempt to cancel out the zero-point offset exactly, I’ve settled for an approximate offset to cancel out most of the zero-point offset.

So, here’s the comparison of global average temperature:

global2.jpg

Likewise, here’s the comparison for just the lower 48 states of the U.S.:

usa482.jpg

UPDATE#3 UPDATE#3 UPDATE#3

By request, I’ll post the comparison between NASA GISS temperature estimates and satellite measurements, using not the corrected, but the UNcorrected GISS data:

usa483.jpg

UPDATE#4 UPDATE#4 UPDATE#4

John Willit believes that the monthly data (rather than annual averages) for satellite temperature estimates establish a cooling trend:

Selective data use again.

The RSS anomaly from February 1981 is +0.183C while the anomay from June 2007 is only +0.139

By my math, that is 0.044C of cooling over the past 28 years 4 months.

Show the monthly data instead.

Let’s look at the monthly satellite data (black dots), a trend-line fit to that data (red line), and John Willit’s method of identifying a cooling trend (blue line):

willit.jpg

By the way, the most recent month isn’t June 2007 at 0.139, it’s July 2007 at 0.218.

UPDATE#5 UPDATE#5 UPDATE#5

Someone on RealClimate asked a question about the difference between Northern hemisphere and Southern hemisphere temperatures. So, I’m using this post as a placeholder, to show a graph of the difference, (northern) - (southern) hemisphere temperature, based on NASA GISS data:

UPDATE #6 UPDATE #6 UPDATE #6

By request, I’ll post the before-adjustment U.S. temperature data. NOTE: I don’t generally like doing this, I’m not a data clearinghouse, but as this is no-longer-current data and I’m not sure where to get it online, I’ll make an exception.

Contiguous 48 U.S. Surface Air Temperature Anomaly (C)
——————————————————
year Annual_Mean 5-year_Mean
———————————
1880 ~~ -0.41 ~~ 0.13
1881 ~~ 0.15 ~~ -0.14
1882 ~~ -0.04 ~~ -0.34
1883 ~~ -0.7 ~~ -0.36
1884 ~~ -0.73 ~~ -0.44
1885 ~~ -0.5 ~~ -0.48
1886 ~~ -0.25 ~~ -0.39
1887 ~~ -0.21 ~~ -0.19
1888 ~~ -0.28 ~~ -0.05
1889 ~~ 0.28 ~~ -0.04
1890 ~~ 0.23 ~~ -0.1
1891 ~~ -0.24 ~~ -0.17
1892 ~~ -0.47 ~~ -0.21
1893 ~~ -0.66 ~~ -0.39
1894 ~~ 0.11 ~~ -0.31
1895 ~~ -0.69 ~~ -0.24
1896 ~~ 0.17 ~~ -0.14
1897 ~~ -0.12 ~~ -0.25
1898 ~~ -0.17 ~~ 0
1899 ~~ -0.43 ~~ -0.02
1900 ~~ 0.54 ~~ -0.01
1901 ~~ 0.07 ~~ -0.11
1902 ~~ -0.09 ~~ -0.11
1903 ~~ -0.65 ~~ -0.31
1904 ~~ -0.41 ~~ -0.34
1905 ~~ -0.47 ~~ -0.37
1906 ~~ -0.06 ~~ -0.21
1907 ~~ -0.22 ~~ -0.18
1908 ~~ 0.11 ~~ -0.02
1909 ~~ -0.25 ~~ 0.01
1910 ~~ 0.31 ~~ -0.12
1911 ~~ 0.11 ~~ -0.17
1912 ~~ -0.89 ~~ -0.11
1913 ~~ -0.13 ~~ -0.21
1914 ~~ 0.03 ~~ -0.33
1915 ~~ -0.16 ~~ -0.36
1916 ~~ -0.51 ~~ -0.32
1917 ~~ -1 ~~ -0.36
1918 ~~ 0.02 ~~ -0.42
1919 ~~ -0.15 ~~ -0.1
1920 ~~ -0.45 ~~ 0.12
1921 ~~ 1.08 ~~ 0.1
1922 ~~ 0.11 ~~ -0.01
1923 ~~ -0.09 ~~ 0.15
1924 ~~ -0.7 ~~ -0.05
1925 ~~ 0.38 ~~ -0.04
1926 ~~ 0.04 ~~ -0.01
1927 ~~ 0.16 ~~ 0.02
1928 ~~ 0.05 ~~ -0.03
1929 ~~ -0.54 ~~ 0.16
1930 ~~ 0.11 ~~ 0.12
1931 ~~ 1 ~~ 0.24
1932 ~~ -0.01 ~~ 0.6
1933 ~~ 0.66 ~~ 0.58
1934 ~~ 1.24 ~~ 0.42
1935 ~~ 0.05 ~~ 0.4
1936 ~~ 0.18 ~~ 0.43
1937 ~~ -0.12 ~~ 0.34
1938 ~~ 0.78 ~~ 0.34
1939 ~~ 0.8 ~~ 0.41
1940 ~~ 0.04 ~~ 0.45
1941 ~~ 0.54 ~~ 0.32
1942 ~~ 0.07 ~~ 0.18
1943 ~~ 0.16 ~~ 0.17
1944 ~~ 0.09 ~~ 0.2
1945 ~~ -0.01 ~~ 0.2
1946 ~~ 0.67 ~~ 0.15
1947 ~~ 0.09 ~~ 0.17
1948 ~~ -0.08 ~~ 0.13
1949 ~~ 0.18 ~~ -0.08
1950 ~~ -0.23 ~~ -0.04
1951 ~~ -0.38 ~~ 0.15
1952 ~~ 0.3 ~~ 0.28
1953 ~~ 0.88 ~~ 0.31
1954 ~~ 0.82 ~~ 0.44
1955 ~~ -0.05 ~~ 0.41
1956 ~~ 0.28 ~~ 0.25
1957 ~~ 0.14 ~~ 0.12
1958 ~~ 0.07 ~~ 0.09
1959 ~~ 0.16 ~~ 0.03
1960 ~~ -0.22 ~~ 0
1961 ~~ 0 ~~ 0.02
1962 ~~ -0.02 ~~ -0.03
1963 ~~ 0.19 ~~ 0
1964 ~~ -0.08 ~~ -0.05
1965 ~~ -0.12 ~~ -0.07
1966 ~~ -0.24 ~~ -0.16
1967 ~~ -0.1 ~~ -0.19
1968 ~~ -0.27 ~~ -0.19
1969 ~~ -0.23 ~~ -0.16
1970 ~~ -0.12 ~~ -0.22
1971 ~~ -0.1 ~~ -0.11
1972 ~~ -0.36 ~~ -0.04
1973 ~~ 0.25 ~~ -0.05
1974 ~~ 0.15 ~~ -0.08
1975 ~~ -0.2 ~~ 0.07
1976 ~~ -0.23 ~~ -0.09
1977 ~~ 0.36 ~~ -0.23
1978 ~~ -0.51 ~~ -0.15
1979 ~~ -0.58 ~~ 0.03
1980 ~~ 0.22 ~~ -0.12
1981 ~~ 0.65 ~~ -0.01
1982 ~~ -0.36 ~~ 0.1
1983 ~~ 0.01 ~~ -0.02
1984 ~~ 0.01 ~~ -0.01
1985 ~~ -0.41 ~~ 0.23
1986 ~~ 0.73 ~~ 0.3
1987 ~~ 0.84 ~~ 0.26
1988 ~~ 0.33 ~~ 0.52
1989 ~~ -0.17 ~~ 0.51
1990 ~~ 0.88 ~~ 0.41
1991 ~~ 0.69 ~~ 0.26
1992 ~~ 0.31 ~~ 0.38
1993 ~~ -0.43 ~~ 0.28
1994 ~~ 0.47 ~~ 0.1
1995 ~~ 0.35 ~~ 0.05
1996 ~~ -0.18 ~~ 0.38
1997 ~~ 0.05 ~~ 0.48
1998 ~~ 1.25 ~~ 0.54
1999 ~~ 0.94 ~~ 0.55
2000 ~~ 0.65 ~~ 0.88
2001 ~~ 0.89 ~~ 0.76
2002 ~~ 0.67 ~~ 0.68
2003 ~~ 0.65 ~~ 0.75
2004 ~~ 0.54 ~~ *
2005 ~~ 0.99 ~~ *
——————————————————

Categories: Global Warming · climate change

41 responses so far ↓

  • Brian // Aug 12th 2007 at 6:39 pm

    tamino….a graph is worth a 1,000 words, especially in this case …. thanks (yet again)

  • Paul G // Aug 12th 2007 at 6:51 pm

    There has been a lot on inane chatter from all sides on this issue. The correction however, is significant.

    The increase in the trend in the US has been lowered dramatically for the last several years. I am still curious as to how this correction compares with the satellite data for the US now. Do the two data sets match up more closely or do they diverge?

    [Response: See the update to this post for a comparison of GISS to satellite data, both for the globe as a whole, and for just the lower 48 states of the U.S.]

  • Nils Simon // Aug 12th 2007 at 7:52 pm

    Paul, there are two different trends for the satellite temperature measurements. According to Wikipedia (for sources see the article):
    # RSS v3.0 finds a trend of +0.181 °C/decade
    # UAH analysis finds +0.14 °C/decade

    That’s the global figure (much more interesting for me here in Europe than only having your 2% of Earth’s surface analysed). I don’t know whether there exists a figure only for the US. We can at least be sure of one thing: Globally the match or dismatch between station measurements and satellite measurements was not even affected at the microscopic level.

  • Petro // Aug 12th 2007 at 9:42 pm

    PaulG, you have assured you believe in global warming trend. You have also suggested that the size of the warming trend matters. So, please, tell us what is the size of the trend, your mind is willing to accept? This would be really helpful to understand your postings here and other forums.

  • Heiko Gerhauser // Aug 12th 2007 at 10:32 pm

    Could you add before and after GISS surface data for the lower 48 graph? (I am not sure which set you are plotting, probably the corrected?).

    And a question on the global satellite data, this looks as if 2005 is nearly 0.2C colder on the satellite data than 1998, while the surface stations indicate 2005 to be warmer than 1998?

    [Response: This comparison uses the “after” data. I’ll track down the “before” data.]

    [Response #2: Done (see UPDATE #3)]

  • ks // Aug 12th 2007 at 10:44 pm

    from this data it looks like the US is warming at a rate 60% faster than the globe according to the satellite data (76% for surface temp data) from 1979-present after the recent adjustment that decreased the US record by 0.15 C. is that correct? if so, that seems like an interesting statistic to point out.

    [Response: Yes, it’s correct. Because the oceans have so much thermal inertia, land warms faster than ocean.]

  • N. Johnson // Aug 12th 2007 at 11:00 pm

    Just FYI, the analysis comparing MSU measurements with the GISStemp is the same for the UAH data too.

  • John Willit // Aug 12th 2007 at 11:35 pm

    Selective data use again.

    The RSS anomaly from February 1981 is +0.183C while the anomay from June 2007 is only +0.139

    By my math, that is 0.044C of cooling over the past 28 years 4 months.

    Show the monthly data instead.

    http://www.remss.com/pub/msu/monthly_time_series/RSS_Monthly_MSU_AMSU_Channel_TLT_Anomalies_Land_and_Ocean_v03_0.txt

    [Response: Congratulations. You’ve prompted me to update this post for a record 4th time. Everyone should take a look at UPDATE #4 (at the end, just before the comments), and decide for themselves who’s guilty of “selective data use.”]

  • Top English WP Blogs « KHỦNG LONG IT // Aug 13th 2007 at 12:36 am

    […] Before and After The global-warming-denialist blogosphere is aflutter. News of the recent correction to USHCN temperature data has […] […]

  • Paul G // Aug 13th 2007 at 3:53 am

    Thanks tamino for posting that information; it was informative.

    == Petro said: ==
    ==”PaulG, you have assured you believe in global warming trend. You have also suggested that the size of the warming trend matters. So, please, tell us what is the size of the trend, your mind is willing to accept? This would be really helpful to understand your postings here and other forums.”==

    I do accept it is warming, I do not accept the majority of the alarmism peddled in the media.

    That there is a warming trend is less important to me then the strength of the trend so accuracy of the data is paramount.

    That a pain in the buttocks character named McIntyre could easily discover a warming error of .15 degrees over 7 years that had eluded specialists trained in detecting temperature anomalies is astounding also.

    As for surface stations, auditing the data is good, and photographing surface sites in violation of NOAA standards is good too. So far, there has been no valid explanation as to why violation of standards has been allowed to occur at various sites.

    So I accept there is a warming trend but that does not mean I accept some of the foolish justifications defending some of the shakier assumptions (and muddled data) around it.

  • ks // Aug 13th 2007 at 6:22 am

    I’m not 100% on this, but McIntyre did not discover that there was a warming error, just that there was a jump in the record. The “specialists” were the ones that corrected the jump, resulting in a correction that reduced the recent years. I think he is trying to take credit for more than he actually did. According to Gavin, at the time McIntyre pointed out the jump, it was unclear which way the corrections would adjust the record.

  • bigcitylib // Aug 13th 2007 at 12:54 pm

    Paul,

    The standards claim that data from sub-par stations should be kept and the siting improved at the next re-location. Meanwhile, the data from the stations is still collected. Why is that not valid?

    Incidentally, Watts has surveyed 281 stations as of this morning, and bitched/whined/complained about 28. So one in ten for a survey generally tilted to Urban stations, where siting problems are more likely to occur.

    That doesn’t sound too bad to me.

  • dhogaza // Aug 13th 2007 at 5:23 pm

    Everyone should take a look at UPDATE #4 (at the end, just before the comments), and decide for themselves who’s guilty of “selective data use.”

    Did he *really* just connect the two endpoints of his dataset du jour and call that a trend line?

    PaulG:

    That a pain in the buttocks character named McIntyre could easily discover a warming error of .15 degrees over 7 years that had eluded specialists trained in detecting temperature anomalies is astounding also.

    *shrug* embarrassing, but astounding? Nothing in the amended data means diddly in the big picture, so it doesn’t really surprise me that it wasn’t caught.

    McIntyre’s done a great job in publicizing his coup, of course, while doing a poor job of (ahem) communicating (ahem) its lack of significance.

    If the man were interested in honesty, he’d correct the syncophants who he allows to post at his blog, not to mention the likes of Limbaugh, etc.

    As for surface stations, auditing the data is good

    Yes! Analysis can tell us what we need, glad to see you understand.

    and photographing surface sites in violation of NOAA standards is good too.

    Certainly doesn’t follow from this episode. It was analysis, not photography, that led to the coup.

  • Paul G // Aug 13th 2007 at 6:16 pm

    == ks said: ==
    =”The “specialists” were the ones that corrected the jump, resulting in a correction that reduced the recent years.”=

    How did these “specialists” miss this jump in the first place? Of course they had to correct it, it was their mistake. :)

    == bigcitylib said: ==
    =”The standards claim that data from sub-par stations should be kept and the siting improved at the next re-location. Meanwhile, the data from the stations is still collected. Why is that not valid?”=

    I believe the concern is the integrity of the past data which the new stations (CRN I assume you are referring to) will not address.

    == dhogaza said: ==
    (My quote: . . . and photographing surface sites in violation of NOAA standards is good too. )

    =”Certainly doesn’t follow from this episode. It was analysis, not photography, that led to the coup.”=

    Photographs of the Minnesota Lakes surface site
    led to the discussion and debate between Climate Audit and Eli Rabett’s blog which led to the discovery of the error. The photographs inadvertently led to the discovery of the error.

  • drhealy // Aug 13th 2007 at 6:59 pm

    Re: bigcitylib’s comment: “Incidentally, Watts has surveyed 281 stations as of this morning, and bitched/whined/complained about 28. So one in ten for a survey generally tilted to Urban stations, where siting problems are more likely to occur.

    That doesn’t sound too bad to me.”

    My wife and I have surveyed 14 sites in Oregon and Washingtion. Unfortunately, only a couple of those appear to fully meet the NOAA siting requirements. Most violate the guidelines to a considerable degree (pun intended). At the Cottage Grove, Oregon station, the station is not even close to the location shown on the MMS system. It is over a mile away and almost 300 feet higher in elevation.

    If these ratios hold up after all stations are checked, it would appear that instead of 90 percent being in compliance, it will be more like 90 percent not meeting requirements: A very sad commentary on quality control within NOAA and NASA on the climate front (again, pun intended).

  • dhogaza // Aug 13th 2007 at 8:23 pm

    Most violate the guidelines to a considerable degree (pun intended).

    How many degrees? C or F? Have you measured how much difference the siting errors you claim exist impact the temperature readings the sites yield?

    What are the histories of the sites?

    What is the GISS doing with the data from these sites? Adjusting them? Rejecting them due to large unexplainable variability in the data?

    How do we know that the trend data from these sites is inaccurate from your photos?

    I’d like some quantitative specifics, if you don’t mind.

  • dhogaza // Aug 13th 2007 at 8:27 pm

    The photographs inadvertently led to the discovery of the error.

    But, of course, the error that was discovered had nothing to do with the sites themselves, simply in the way the data was processed before it was given to NASA.

    Why didn’t they just sit down and examine the data in the first place, rather than embarking in this silly exercise in photography?

    I know why: they weren’t actually expecting to uncover any mistakes of this sort. The photos are there for propaganda purposes only. “this photo shows a site that doesn’t look good, therefore global warming is a fraud”.

  • Paul G // Aug 13th 2007 at 11:37 pm

    == dhogaza said: ==
    =”But, of course, the error that was discovered had nothing to do with the sites themselves, simply in the way the data was processed before it was given to NASA.”=

    Of course the error affected the sites; the error was incorporated into the sites data; data that may well have already been used by other scientists.

    =”Why didn’t they just sit down and examine the data in the first place, rather than embarking in this silly exercise in photography?”=

    Now you are harping about how they found the error? The how matters little.

    As for the photos, I find them quite interesting. Some definitely seem to demonstrate a laxness of standards enforcement; however their effect, or lack of, on temperature data remains speculative at present.

  • ks // Aug 14th 2007 at 4:13 am

    Paul,

    I was just addressing your claim - “That a pain in the buttocks character named McIntyre could easily discover a warming error of .15 degrees over 7 years that had eluded specialists trained in detecting temperature anomalies is astounding also.”

    when I said -”McIntyre did not discover that there was a warming error, just that there was a jump in the record. The “specialists” were the ones that corrected the jump, resulting in a correction that reduced the recent years.”

    in other words, McIntyre didn’t discover that it was a warming error since it wasn’t a warming/cooling error until the calculations were done by the trained analysts. all I was saying is that your phrasing made it sound as though McIntyre did more work than he did, namely that he was actually capable of doing the corrections himself.

    meanwhile your response to my last comment went off topic. I was specifically addressing McIntyre’s role, no more, no less.

    p.s. “specialists” was your term. it came across to me that you took issue with my using it.

  • dhogaza // Aug 14th 2007 at 3:56 pm

    dhogaza:
    ”But, of course, the error that was discovered had nothing to do with the sites themselves, simply in the way the data was processed before it was given to NASA.”
    Paul G:

    Of course the error affected the sites;

    I’ll stand by my original quote, thank you very much.

    Just how did the error, which was downstream from the sites themselves, affect the sites? Were the tapes given to NASA later dropped on top of the thermometers onsite, somehow knocking them out of whack?

    Now you are harping about how they found the error? The how matters little.

    Of course it matters. The effort being spent driving round photographing sites (emitting CO2 in the process) could be better used data mining, looking for more strangeness that might or might not already be taken into account by the GISS analysis.

    The key here is that the surfacestation folks claim that data analysis is useless for correcting problems with the data set.

    Then, of course, with McIntyre’s help they used data analysis to find a problem with the data set (though it took people who have expertise with the two sets of data to fix it).

  • Magnus Andersson // Aug 14th 2007 at 5:08 pm

    At all dots in you first charts in this post it can’t possibly be more than a 0.01 difference between before and after.

    Now, the actual difference, due to the changed numbers by NASA, is for som of the 10 latest years 0.002 degrees or more, and for one years in the 1980s (if I’m not totally wrong) at least 0.004 degrees.

    So your chart seems to be nothing but a fraud.

    Sorry.

    [Response: Your comment is — to put it plainly — nonsense. By which I mean, it makes no sense at all.

    Sorry.]

  • Paul G // Aug 14th 2007 at 5:41 pm

    == dhogoza said: ==
    =”Just how did the error, which was downstream from the sites themselves, affect the sites? “=

    All the individual sites have had their individual records modified.

    =”The effort being spent driving round photographing sites (emitting CO2 in the process) could be better used data mining, looking for more strangeness that might or might not already be taken into account by the GISS analysis.”=

    Well, quite a bit of strangeness is showing up in some of the photographs. Overrealiance on data mining may not be effective in locating all data anomalies.

    =”The key here is that the surfacestation folks claim that data analysis is useless for correcting problems with the data set.”=

    I have not heard that claimed. What I have heard is that the data analysis may not be up to the task of fixing unknown surface site contaminations.

    =”Then, of course, with McIntyre’s help they used data analysis to find a problem with the data set (though it took people who have expertise with the two sets of data to fix it).”=

    The experts have their underwear around their ankles on this one. Or course they were the only ones who could “fix” it, they are the only ones with the code to do so.

  • Magnus Andersson // Aug 14th 2007 at 7:25 pm

    After some search the No Name administrator of this blog wrote: “Your comment is — to put it plainly — nonsense. By which I mean, it makes no sense at all. Sorry.”

    My claim is not nonsense at all. Here are the figures:

    http://www.smalldeadanimals.com/images/leaderboard.jpg

    A “differences leaderboard” for the warmest years the last decades; no order for smaller difference than 0.01 .

    DIFF YEAR
    0.14 2001 (old 0.90, new 0.76)
    0.10 2006 (old 1.23, new 1.13)
    0.01 1990
    0.01 1998
    0.01 1999

    As you see, your plot isn’t possibly correct for 2001 and 2006. Correct me if I’m wrong.

    [Response: Re-read your original comment. You said, “for som of the 10 latest years 0.002 degrees or more, and for one years in the 1980s (if I’m not totally wrong) at least 0.004 degrees.” It looks like you made an error of decimal places in your original comment, which made it utter nonsense.

    While you’re at it, re-read the post. The figures you’ve given in this comment are for the LOWER 48 STATES OF THE U.S. ONLY. It’s abundantly clear that this post is about the GLOBE, and the first several graphs are of GLOBAL temperature, both before and after the correction is applied. You’ll also see that the 6th and 7th graphs in this post compare the lower-48-US-states-only temperature to the estimates for the same geographic region from satellite measurements, the 6th figure showing after-correction data while the 7th shows before-correction data. The data in these graphs, and the data in the first several graphs (for the globe as a whole), are correct. Your accusation of “fraud” is completely mistaken, based on nothing but sloppy reading, and rooted in an ideology which precludes — even disdains — truth.]

  • Magnus Andersson // Aug 14th 2007 at 11:24 pm

    Okay. My forst was wrong (and I also by mistake put two extra zeroes in two numbers.

    Okay. But the fact that the impact from 0.15 degree in US is extremely small on the global figures is so self-evident that I think no one should bother to show it in a diagram. But you’re welcome, anyway!

    Why do you say I’m rooted in an ideology?

    ou also starts yor post with “The global-warming-denialist…”. Is that political, or?

    Is the rest of the world not using that particular adjustment code or do they have other bugs? No one knows. We have only a description of what is done mixed by defence of what is done et cetera. No description covering the tiniest details of computation. I think all code shal be public domain. I think it’s needed for a more detailed discussion of the result and the impact from different adjustments made. We really don’t know which stations which are removed due to e.g. non-rural impact, how the calibration of weight numbers deciding what is within and without a trend is, maybe time constants and more. The whole code needs to be open. Otherwise I don’t think we really don’t know the implementation of rules described in their details.

    [Response: You say, “the fact that the impact from 0.15 degree in US is extremely small on the global figures is so self-evident that I think no one should bother to show it in a diagram.” If it’s self-evidently so extremely small, then why have denialists been making such a big deal about it?

    You wonder why I say you’re rooted in an ideology. It’s because even though you were blatantly mistaken, and I had the right numbers all the time, you didn’t bother to investigate carefully — you accused me of fraud. That seems to me to be the work of an ideologue.]

  • Magnus Andersson // Aug 14th 2007 at 11:25 pm

    Oops. The 3rd and 4th paragraph was ment to be the last ones. But never mind!

  • John Mashey // Aug 15th 2007 at 12:57 am

    Magnus: your blog’s first article uses as sources:

    - The Reference Frame
    - NewsBusters
    - ClimateAudit

  • Mario // Aug 15th 2007 at 10:52 am

    I am the guy who, as you write here: “on RealClimate asked a question about the difference between Northern hemisphere and Southern hemisphere temperatures”.

    I would like to tank for the kind answers I got, and also to add some remark,

    but when I tried to post on Realclimate, Gavin would noy accept it

    (and it seems as, because of this last post, he had now also disabled my write-access to threads)

    Here is the exact text of my “refused post”
    this seems to me the far better place to send it to…

    Re: #197-198 Tamino

    Many thanks again for the effort in producing a well documented answer to my naive doubts

    your graph at
    http://tamino.files.wordpress.com/2007/08/nh-sh.jpg
    on the northern-southern hemisphere temperature anomaly is really interesting and thought provoking

    For example…

    1. If the main driver of global warming is man-provoked CO2 increase, then it would seem that already in the ’80s of 19th century (!)
    Northern Europe-US “industrial revolution” was somehow able to make itself felt thru a (quite fast) Northern hemisphere differential warming
    True: railways and carbon burning were rising very fast then,
    but can this be enough?
    one could give a look look - say - at figure 2 of
    http://www.epa.gov/climatechange/emissions/globalghg.html

    2. Thermal inertia of the southern oceans must really be “immense”, as you say, because even in recent years, when northerners sulfate aerosols are far in the past, and CO2, with its “7 or 8 months” diffusion time over the globe, the North-South differential is still rising!

    but this - I suppose - could for example be the effect of a possible strong acceleration in recent northern CO2 emissions…

    3. But then another notable kind of “thermal inertia” must be operating in the US, otherwise, after the demise of sulfate aerosols, one could expect a quick alignment to - say - a kind of northern hemisphere mode,

    that is a QUICKER warming “to recover lost time”, so to say.

    On the contrary, now US among the northern regions seem to be the warming laggard,
    as the sulfate aerosols era had left a lasting heritage…

    Now if we assume some kind of big “thermal inertia” all can be neatly explained, and this is perhaps the correct thing to do,

    but then

    unless we also find a robust way of independently verifying and measuring “thermal inertia”,

    admission in the discourse of this additional “free entity” reduces greatly the forcefulness of our theoretical construction,
    because other competing explanations of global warming would become workable too:

    because it is enough that these “competitor theories” adjust the non-directly-measured-but-conveniently-assumed “free entity” at the level that best fits their needs.

    One would then be forced then to admit a higher level of ignorance on climate mechanisms than it’s pleasant to do.

    [Response: Don’t be too sure you’ve been “banned” at RealClimate, or that your post was rejected. The internet behaves oddly sometimes, and it occasionally happens that one of my posts at RC, which has nothing even possible objectionable, simply vanishes; I attribute it to a bug in the blog system.

    That thermal inertia exists (and is much greater for the oceans than land) is quite robustly established. It’s part of the basic theory of heat transfer, and has been known since long before global warming was identified.]

    [Response #2: I was just at RC, and your comment has appeared there. It sometimes takes a while for comments to be moderated, especially if the comment contains multiple links; then it may be sent to the “spam cue” rather than the “moderation cue.” It happens to all of us — after all, they have jobs and lives.]

  • J // Aug 15th 2007 at 2:38 pm

    Unless you’re playing pool, I think you mean “queue” rather than “cue”, Tamino.

    This post of yours is excellent, by the way. The graphs comparing satellite-derived and surface-measured T get the point across perfectly. It’s especially nifty seeing how this adjustment of the US surface T record brings the data for the lower 48 states into such close agreement with the satellite TLT data. Thanks again for doing this.

  • J // Aug 15th 2007 at 2:50 pm

    Mario wrote:

    > 2. Thermal inertia of the southern oceans must really be “immense”, as you say […]

    Water has a very high volumetric heat capacity. Typical land-surface materials (granite, sand, soil, etc.) have heat capacities ranging from 0.75 to 0.9 joules per gram per kelvin.

    In contrast, water has a heat capacity of 4.2 j g-1 K-1. In other words, it takes 4-5 times as much energy to raise a quantity of “ocean” by one degree as it would take to raise the same amount of “land” by one degree. And there’s a lot less land in the southern hemisphere.

    (Yeah, this is just a first-order approximation, sorry…)

  • Hank Roberts // Aug 15th 2007 at 3:24 pm

    for “cue” read “queue” (or “bucket”) ….

    nitpicking, basic primate social behavior ….

    yep, sometimes posts take forever to show up. I think it varies according to what particular automated spam is being dumped into the Intertubes, adjusting for words that are in the spammers’ current garbage.

    Sometimes you can’t say “rate” and “percent” and “amount” in the same posting without it getting held up — I guess til someone can review it and make sure it’s not part of a current flood of mortgage spam, over at RC, I’ve noticed. Other weeks that would get by the automated guardians.

  • Mario // Aug 15th 2007 at 4:09 pm

    J wrote:

    > it takes 4-5 times as much energy to raise a quantity of “ocean” by one degree as it would take to raise the same amount of “land” by one degree. And there’s a lot less land in the southern hemisphere.

    OK… this explains south emisphere delay in getting even with the fast warming northern one,

    but it seems not well in line with the recent (that is: after sulfate aerosols demise) slower growth of US “land” temperatures compared with the rest of northern hemisphere .

    [Response: Have you run the numbers? For GISS data from 1975 to the present (the “modern global warming era”), the trend in lower-48 U.S. temperature is 3.04 deg.C/century, the trend for the northern-hemisphere land stations is 3.03 deg.C/century.]

  • John Mashey // Aug 15th 2007 at 7:23 pm

    re: Mario
    Brife note: “after sulfate aerosols demise”, I think you mean flattening or downturn.

    Sulfates are hardly dead, even in the US & Europe!
    http://www.pnl.gov/main/publications/external/technical_reports/PNNL-14537.pdf
    In 2000, worldwide, we were still about 2X higher than we were around 1950, even though we’re lower than the peak around 1975.

    One might interpret that as:
    a) For a while the big rise in SO2 emissions was able to mask the GHG-warming.
    b) Then, when SO2 peaked and was reduced (for a while, I don’t know where China’s going to end up), even though the SO2 emissions are 2X higher than they were in 1950, the GHG-warming them…

  • John Mashey // Aug 15th 2007 at 7:24 pm

    OOps, last sentence was supposed to be:
    ..”The GHG-warming is overpowering them.”

  • Mario // Aug 15th 2007 at 9:32 pm

    Sorry, in fact I hadn’t looked at the NASA numbers, but only at the NASA graphs,

    without noticing that the much more dramatic northern hemisphere temperature upward-slope is produced by the choice of a different, and much lower, y-axis scale factor

    Many thanks

    now the only strangeness I can see in the CO2 explanation,

    is that in your graph, the northern hemisphere seems starting its relative warming (at a rate fast and near to the present one) too soon

    that is already in 1880, when CO2 emissions and percentual increase, should have been only a small fraction of the present ones…

  • John Mashey // Aug 16th 2007 at 5:00 am

    Mario: for any of these charts, drawing strong conclusions about CO2 effects from just a few points is basically impossible, given the nubmer of otehr moving parts in the climate system.

    But, in particular:
    1) El Ninos and La Ninas matter.
    2) So do volcanoes, including where they are, and whether they happen to stomp on an El Nino or La Nino, either canceling some of the former or amplifying the latter.
    3) Then there’s the sulfate business (localized) and soot (localized). in opposite directions.

    Fig 2 in
    http://data.giss.nasa.gov/gistemp/2005/ is a nice presentation which shows items 1) and 2), helping the reader understand strong, quick transients.

    I won’t try to figure out what ENSOs were doing back then, but we know volcanoes cause major gyrations, and 1883 (Krakatoa) was one of the most major. Anyway, vague feelings about slopes go out the window when faced with (especially) major volcanoes or big ENSOs. This is like trying to weigh yourself while keeping a frisky pet elephant in the room.

  • Mario // Aug 16th 2007 at 7:09 am

    Your reference is quite interesting: looking at these data one finds other reasons to wonder “what percentage” of 20th century temperature variations can be explained by a simple “CO2 warms but sulfates cool” schema.

    We would rather need an estimate of “short life” sulfates presence in the air, but these European emission data are so impressive to suggest by themselves that in the 40-75 cooling trend Europe should have been the world leader. And for this some confirmation can be found. For example:
    http://www.usefulinfo.co.uk/globalclimate/table_europe.htm

    But if sulfates cooling is effective (and linear), the early start - even before 1900 - of a relatively high emission level interacting with an, at those times, comparatively low CO2 emission levels, make it difficult, as I see it, to justify as CO2-produced the 1880-1940 warming period.

    On the relatively low beginning 20th century CO2 emission see for example
    http://www.epa.gov/climatechange/emissions/globalghg.html
    and from figure 2 also notice how much “long life” CO2 emission must be added in the earth atmosphere, in order for CO2 to take, in the late ‘80s, climate command from “short life” cooling sulfates.

  • Ian // Aug 16th 2007 at 6:24 pm

    Thanks for another fun post, Tamino.

    So far, many people seem to be talking about the correction as if it’s the record for the whole US being changed, not for the lower 48 states - what does the US record look like if you INCLUDE Alaska? What I’d really like to see is how 1998 and the years around it compare with the 1930s record if you include Alaska? Is it part of a convention to leave Alaska out of these US averages?

    Thanks again!

  • Adam // Aug 17th 2007 at 8:51 am

    I think it is, as Alaska is (a) not a contiguous part of the region defined by the “lower 48″ and (b) it is (mainly) in a different latitude band. It’s probably better thrown in with Canada if anyone.

    Alaska has warmed a lot (probably in part due to polar amplification as it coincides with a similar rise in Siberia). So if it was included it would raise the average temperature rise for the US.

  • TCO // Aug 18th 2007 at 1:40 pm

    1. Very nice graphs. Kudos.

    2. The lowest level of the denialist scene is confusing US versus World etc. impact of the Hansen error. However, the Warmer crew is only addressing that overemphasis and doing so is tendentious. for instance:
    -the error is more than .15 at the individual station level (it’s bimodal but with a magnitude of about 0.5) so analyses using individual stations if they have used the corrected versions may be impacted significantly.
    -the error had existed for years
    -the error was uncovered by looking at end product (code or an “exact” algorithm, vice general handwaving description, was not available)
    -Steve actually DID hypothesize the source of the error, not just the jump in the values. I was confused about this at first, but go look at his email to NASA.

    [Response: My understanding is that the error had nothing to do with the algorithms (which by the way *are* available, just not the actual computer code), but was due to the erroneous combining of different records which were incorrectly supposed to be the same station. Also, that the error was at USHCN, not NASA GISS, so it certainly had nothing to do with Hansen or his team.

    Anybody have more info?]

    [Response #2: Gavin Schmidt has notified me that my understanding was incorrect. The error was NASA’s and NASA’s alone.]

  • TCO // Aug 28th 2007 at 9:33 am

    Actually I think Steve did hypothesize the cause of the problem. (not just that there was a jump but why.) I was confused from looking at in process speculation. But if you look at his email, he had figured it out.

  • Georg Hoffmann // Aug 31st 2007 at 6:53 am

    Dear Tamino
    do you have a link where I can find the “old” uncorrected data for the US48? If there is no public link could you send your data to my e-mail account?
    Thanks and go on with your excellent work!
    Georg

    [Response: I’ve added it as a final update to the post.]

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