Guest post by David Middleton
The headline was, of course accompanied by nonsense like this…
Senior Meteorologist Stu Ostro (Twitter) says, “Exceeding July 1936 at the peak of the Dust Bowl heat — is BIG.”
The “record” is less than 120 years long. The warmest month on record in the US, isn’t any more significant to climate change than this past weekend’s abnormally cool weather was.
NOAA’s hottest month ever is based on the homogenized US Historical Climatology Network (USHCN). THe USHCN is a subset of the GHCN…
Investigation of methods for hydroclimatic data homogenization
Steirou, E., and D. Koutsoyiannis, Investigation of methods for hydroclimatic data homogenization, European Geosciences Union General Assembly 2012, Geophysical Research Abstracts, Vol. 14, Vienna, 956-1, European Geosciences Union, 2012.
We investigate the methods used for the adjustment of inhomogeneities of temperature time series covering the last 100 years. Based on a systematic study of scientific literature, we classify and evaluate the observed inhomogeneities in historical and modern time series, as well as their adjustment methods. It turns out that these methods are mainly statistical, not well justified by experiments and are rarely supported by metadata. In many of the cases studied the proposed corrections are not even statistically significant.
From the global database GHCN-Monthly Version 2, we examine all stations containing both raw and adjusted data that satisfy certain criteria of continuity and distribution over the globe. In the United States of America, because of the large number of available stations, stations were chosen after a suitable sampling. In total we analyzed 181 stations globally. For these stations we calculated the differences between the adjusted and non-adjusted linear 100-year trends. It was found that in the two thirds of the cases, the homogenization procedure increased the positive or decreased the negative temperature trends.
[…]
Poor station siting in the USHCN is also the reason that NOAA’s new U.S. Climate Reference Network (USCRN) shows July 2012 to be 75.5°F (about 2°F cooler than the USHCN. The homogenized USHCN supports AGW by artificially cooling the past and artificially warming the present.
While there are valid technical reasons for homogenizing the older records to account for changes in methods, instruments, station location and environmental alteration around stations… The methods used to homogenize the data induce artificial warming. This is a cold, hard, empirical fact. The USHCN data used by NOAA has been artificially cooled in the past in an effort to “homogenize” the older data and methods with the modern data and methods. Remove the homogenization and July 2012 would be 1.0°F cooler than July 1936.
However, even if the homogenization is producing a more accurate temperature record, the “record” is not long enough to say much of anything about climate.
Meteorologically speaking, “climatology” refers to periods greater than 30 years long. “Normal” climatology is generally the most recent 30-yr average. The 30-yr average is climate (what you expect). July and last weekend were weather (what you get). July was significantly warmer than average. Very few months (or weekends) are “average.” Most are above or below average.
Above Normal – One of the outlook categories that are based on the 1981-2010 climatological normal. During this 30 year reference period, average three-month temperature was observed in Above Normal category (10 warmest years) 1/3 (33.3%) of the time.
Anomaly – The deviation of a measurable unit, (e.g., temperature or precipitation) in a given region over a specified period from the long-term average, often the thirty year mean, for the same region.
B – Is used on climate outlooks to indicate areas that will likely be below normal.
Below Normal – One of the outlook categories that are based on the 1981-2010 climatological normal. During this 30 year reference period, average three-month temperature was observed in Below Normal category (10 coolest years) 1/3 (33.3%) of the time.
Climate – Prevailing set of weather conditions at a place over a period of years.
Climate Change – A non-random change in climate that is measured over several decades or longer. The change may be due to natural or human-induced causes.
In reality, climate is a combination of prevailing weather patterns and physical geography. Climatological normals are the mean weather patterns during a 30-yr reference period. Climate change occurs over “several decades or longer.”
NOAA’s NCDC trumpets warm months as all time climate records. The “hottest month on record” in the a NCDC headline is an assertion of climatic significance. When it has no more climatic significance then the coldest August 18-19 on record. Weather records are broken all of the time.
“Climate Normals”
The current climate normals (1981-2010) were adopted on July 1, 2011…
NOAA’s 1981-2010 Climate Normals
NOAA’s National Climatic Data Center (NCDC) released the 1981-2010 Normals on July 1, 2011. Climate Normals are the latest three-decade averages of climatological variables, including temperature and precipitation. This new product replaces the 1971-2000 Normals product. Additional Normals products; such as frost/freeze dates, growing degree days, population-weighting heating and cooling degree days, and climate division and gridded normals; will be provided in a supplemental release by the end of 2011.
The previous climate normals were from 1971-2000. I made an assumption that the climate normals are adjusted once per decade. If my assumption is correct, these are the climate normals reference periods since 1931:
| Decade | Reference Period | Mean July Temp. (° F) |
| 1931-1940 | 1901-1930 | 73.79 |
| 1941-1950 | 1911-1940 | 74.51 |
| 1951-1960 | 1921-1950 | 74.59 |
| 1961-1970 | 1931-1960 | 74.73 |
| 1971-1980 | 1941-1970 | 74.23 |
| 1981-1990 | 1951-1980 | 74.35 |
| 1991-2000 | 1961-1990 | 74.33 |
| 2001-2010 | 1971-2000 | 74.38 |
| 2011-2020 | 1981-2010 | 74.76 |
The NOAA data are available here: NCDC CDO
It appears to me that there is nothing terribly anomalous about the current 1981-2010 reference period. It’s 0.03° F warmer than the 1931-1960 reference period.
Here’s a plot of U.S. July temperatures (1895-2012)…
I’m sure that the actual 2012 July temperature must have been a few 1/100ths of a degree warmer than 77.4°F; otherwise July 2012 is actually a bit cooler than July 1936, despite the homogenization.
Rather than calculate a temperature anomaly relative to a fixed reference period, I decided to calculate it against what I think the contemporaneous reference period would have been (AKA a different take).
Example: The 1931-1940 anomaly is calculated against the 1901-1930 reference period.
Since “climate is what you expect and weather is what you get,” the very hot year of 1936 should be measured against the contemporaneous expectation. Here’s the July temperature anomaly with a different take…
It’s quite evident that July 1936 was a lot hotter than July 2012, relative to what was expected (climatology). One other thing should also be evident. The climate normals of the 20th century did not vary a lot and the current climate normals are not anomalous. The weather has varied a lot, the climate not so much.
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
“Senior Meteorologist Stu Ostro (Twitter) says, “Exceeding July 1936 at the peak of the Dust Bowl heat — is BIG.”
Media manipulative sound bites like that help to make Senior Meteorologist Stu Ostro BIG.
It’s not the vote that counts, it’s who counts the vote that counts.
Is there anywhere a process in the books on how to unwind the obnoxious Carbon-credits in Australia and elsewhere, once the CO2-hysteria has been proven to be a scam beyond doubt?
Three words – “arctic sea ice”. SLB
Oh my Goooorsh..! HOT? Heat??? WTF! (World Trade Federation)!!!
Doesn’t anyone see the problem? TEMPERATURE…INTENSIVE VARIABLE.
HEAT = Temperature + Humidity + Air Pressure = ENERGY CONTENT PER CUBIC METER.
What where the HUMIDITIES in the 1930’s, WHAT ARE THE HUMIDITIES NOW.
If, say for a trivial simple example, it was 86 F and 60% RH in the 1930’s throughout, it would be
roughly 25% HOTTER IN TERMS OF THE ENERGY CONTENT OF A CUBIC METER OF
AIR than would be 105 Degrees and 10% RH.
Yet, by the IMPLICIT DEFINITION HERE… the 105 DEGREE AVERAGE WOULD BE HOTTER.
Excuse me, must go and bang head on wall now…in frustration.
“An inept language usage can never yield a precise communication.” Annon.
[most folk on here don’t really appreciate the need for shouting to make one’s point . . thanks . . kbmod]
It’s shameful that the media isn’t emphasizing that it was hotter in the 1930’s than now. It is also shameful that they don’t emphasize that the central USA is not the entire globe. The globe, overall, has been in a slight cooling trend since 1998.
It’s called ‘global warming’, not, ‘non-record heat for one month in central USA while overall the earth is cooling warming’.
I bristle every time I hear a media meterologist or talking head refer to the present temperature in comparison to “normal”. I absolute fume at the introduction of the word “normal” to describe a mean or median event. The word normal gives people the false sense that things, temperatures, are static events, when really, the “normal” of weather speak is nothing more than a rolling, probably ill contrived, average. This is the kind of crap that gives AGW legs. From “normal” temperature, we get “normal” weather, and therefore “normal” climate, when, in truth there is no such thing.. The AMS, being largely responsible for this, I believe, needs to fix the reporting. Its not over the heads of the audience for the on-air weathertroll to say that today is “85, slightly warmer than today’s 30 yr rolling aveage of 80”. Then perhaps people would begin to understand what weather and climate really is.
http://www.aquapulser.com says:
August 25, 2012 at 7:33 am
“[most folk on here don’t really appreciate the need for shouting to make one’s point . . thanks . . kbmod]”
Maybe. However, he is at least partially right. Temperature by itself doesn’t mean a whole lot, and the physical significance of a spatial average of temperatures is very questionable. However, the equation “HEAT = Temperature + Humidity + Air Pressure” does not have the right units.
I’m not a thermo guy, so I’m not entirely sure how the equation should read, but I think it should be a weighted integral (or, weighted discrete sum since we only have discrete data) with the weights determined by some measure of local heat capacity.
Paul Coppin says:
August 25, 2012 at 9:54 am
Good point.
I checked our airport sensor for the month of July. Not much to see there. One cold extreme, one hot extreme record, the rest bouncing between and within the bands for normal and extremes. And that’s for the airport. So we seem to be…normal…for an airport.
http://www.wrh.noaa.gov/climate/temp_graphs.php?stn=KPDT&wfo=pdt
Why would anyone believe that the conditions of 1936 would not occur again? The fact that they occurred once establishes that they are part of natural variability. Everyone knows that the conditions of 1936 will occur again and that the conditions of 2012 will occur again.
The only answer to my question is because there exists a rich and powerful lobby which constantly bombards everyone with the belief that our day is unique in all of human history. They argue that even if 2012 is a repeat of 1936 and was to be expected at some point, the occurrence of 2012 is more evidence that our times are unique. In other words, they take the fact of natural variability for evidence that natural variability no longer operates in our day. Whew!
So hot lately it even makes things plural – like “…the world champion Miami Heats ….” (as USA Pres. Obama revealed 27 June 2012)
Paul Coppin says:
August 25, 2012 at 9:54 am
Very well said. Very important. Yes the terminology of TV meteorology was ripe for exploitation by the hysterical warmists and it remains so today. Someone in meteorology should make a name for himself by promoting reforms in terminology. Of course, promoting reform will be tough because TV meteorology serves the pocket book of TV station owners and they thrive on sensationalism. But the task is doable. (It is so sad but telling that so-called scientists such as Hansen exploit TV terminology as a matter of course.)
I’ve noticed a strange thing. When I ask people, who seem keen to proclaim some new “record high temperature”, what temperature they think it should be, or what temperature they would like it to be, they become much more reticent. Or even if I ask how rapidly they would like it to change, if at all.
I acknowledge that such things are beyond my jurisdiction. But it seems doubly strange that so many who think science advances by a process of taking a vote, should be so unwilling to express their thoughts or desires when asked to do so.
Lovely bells and whistles and obscure verbiage. However, an easily identifiable point or conclusion would be appreciated – but only in an English translation.
Looking at station temperature records for Prescott, AZ (http://www.wrcc.dri.edu/cgi-bin/cliMAIN.pl?azpres) I see the all-time record high temperature of 105°F was in July 1925. Intellicast historic records agree (http://www.intellicast.com/Local/History.aspx?location=USAZ0178). But when I look at NOAA records for daily max highest (http://www.ncdc.noaa.gov/extremes/records/daily/maxt/1925/07/00?sts%5B%5D=AZ#records_look_up), there is no record high temperature for July 1925 in Prescott.
The same is true for record high of 104°F in June 1924. NOAA says: “didn’t happen.”
Makes me wonder how many of the record number of record highs in July 2012 were actually records.
Paul Coppin said (August 25, 2012 at 9:54 am)
“…I bristle every time I hear a media meterologist or talking head refer to the present temperature in comparison to “normal”. I absolute fume at the introduction of the word “normal” to describe a mean or median event. The word normal gives people the false sense that things, temperatures, are static events, when really, the “normal” of weather speak is nothing more than a rolling, probably ill contrived, average…”
To this, I agree. The scientists can’t even agree what the global 20th century average is. So who’s to say if today’s temperatures are above or below “normal”?
How can “data homogenization” produce a more accurate Temperature record ?
The most accurate Temperature record is the set of numbers that a set of technicians / scientists / engineers / whatever , wrote down after looking at their thermometers. Anything else is bogus; commonly referred to as “falsification”, also known as ” lying / cheating / fakery / whatever, ”
When actual experimentally recorded measurements, are deliberately replaced with made up numbers that were recorded by nobody anywhere, that does not comprise “data gathering.” It is scientific fraud.
Corporate officers of public companies are incarcerated in Federal penitentiaries for “data homogenization.”
Pointing a T&V camera at Britt Hume sitting in an arm chair, with his legs and feet prominently crossed in the characteristic Moslem salute, and flapping his mouth off, in an emulation of Walter Cronkite; rather than pointing that camera at an Olympic Athlete in competition; and presenting this as “The Olympic Games “; that is what “data homogenization” is.
Here in Canada, a magazine article openly said that the 1950’s had record breakers, not 2012. Yes, it was hot, but not all of the U.S. was blistering as it was in the 1930’s. Most parts of the States were cool and had rain. It was no Dustbowl. It makes me angry how people say July was a “record breaker”, when it wasn’t even that! People just jump to conclusions. The alarmists no doubt are calling this past July “a shape of things to come” while conviniently calling us “deniers”.
On another note, it seems H.G. Wells’ pessimisms were indeed correct.
george e smith,
As usual, a very perceptive comment.
This is not directly related to July record temperatures but it is related to the records of teperatures.
In 2007 and in 2012 I got the list of record highs and lows for Columbus Ohio. I’ve compared the record highs that covered up to 2007. Here are the changes made. (I hope this copy/paste works right.)
Newer-April ’12 Older-’07 (did not include ties)
6-Jan 68 1946 Jan-06 69 1946 Same year but “new” record 1*F lower
9-Jan 62 1946 Jan-09 65 1946 Same year but “new” record 3*F lower
31-Jan 66 2002 Jan-31 62 1917 “New” record 4*F higher but not in ’07 list
4-Feb 61 1962 Feb-04 66 1946 “New” tied records 5*F lower
4-Feb 61 1991
23-Mar 81 1907 Mar-23 76 1966 “New” record 5*F higher but not in ’07 list
25-Mar 84 1929 Mar-25 85 1945 “New” record 1*F lower
5-Apr 82 1947 Apr-05 83 1947 “New” tied records 1*F lower
5-Apr 82 1988
6-Apr 83 1929 Apr-06 82 1929 Same year but “new” record 1*F higher
19-Apr 85 1958 Apr-19 86 1941 “New” tied records 1*F lower
19-Apr 85 2002
16-May 91 1900 May-16 96 1900 Same year but “new” record 5*F lower
30-May 93 1953 May-30 95 1915 “New” record 2*F lower
31-Jul 100 1999 Jul-31 96 1954 “New” record 4*F higher but not in ’07 list
11-Aug 96 1926 Aug-11 98 1944 “New” tied records 2*F lower
11-Aug 96 1944
18-Aug 94 1916 Aug-18 96 1940 “New” tied records 2*F lower
18-Aug 94 1922
18-Aug 94 1940
23-Sep 90 1941 Sep-23 91 1945 “New” tied records 1*F lower
23-Sep 90 1945
23-Sep 90 1961
9-Oct 88 1939 Oct-09 89 1939 Same year but “new” record 1*F lower
10-Nov 72 1949 Nov-10 71 1998 “New” record 1*F higher but not in ’07 list
12-Nov 75 1849 Nov-12 74 1879 “New” record 1*F higher but not in ’07 list
12-Dec 65 1949 Dec-12 64 1949 Same year but “new” record 1*F lower
22-Dec 62 1941 Dec-22 63 1941 Same year but “new” record 1*F lower
29-Dec 64 1984 Dec-29 67 1889 “New” record 5*F lower
It’s 2012. Do you know what your records are?
Still an exercise in futility, since an “anomaly” of a mean temperature for the globe, is as meaningless as the mean temperature itself.
While all that heat was baking much of the contiguous US, we were abnormally cool in the Pacififc Northwest, and I don’t think much of the rest of the world was having issues. All of this is much ado about nothing.
That’s not correct. If the data need to be homogenized, it is not falsification.
Data have to be homogenized all of the time. We couldn’t interpret seismic reflection data if we did not homogenize it. If I have two different 2d seismic profiles, shot with different sources, recorded with totally different instruments and field geometries, there is a very high probability that I will have to adjust the data from one profile to tie the other. That is homogenization.
The problem isn’t the fact that the GHCN and USHCN data are homogenized to account for changes in recording parameters. The problem is that the homogenization process appears to be very flawed and that the homogenization adjustment is of the same magnitude as the asserted anomaly.
This is akin to drilling a prospect when the structural relief of the target horizon is the same as the mistie correction (homogenization) of two seismic surveys.
Yes, you are comparing weather events, not climate events.
Your method has essentially removed the long-term trend. In the paragraph you wrote that I’ve cited here is the seed for a much simpler calculation that would do a better job comparing climate instead of weather events.
Select a 30 year period (or 360 months) that includes 1936 – select to get the 30-year period with the highest average temperature. Now calculate the average for the most recent 30 years. You can do this for annual, seasonal or monthly temperatures, and you will still have a climatology instead of a weather comparison.
When measuring weather events, there will always be extremes in the past that compare to today. When talking about climate change, you should talk about long-term trends and long-term averages. This is the point you make yourself as quoted.
I think you will find that if you follow the better method implied by your quote, the difference in climatology will make concerns about adjustments moot.