Guest Submission: Reply to Temperature Complaints

4-10-15

Dear Mr. Seppa,

I have taken the time to review your ten page paper, and what I can do is discuss some of the curious portions that to me, don't seem to provide meaningful time frames, or solid statistical references.

To begin with, I don't understand your implication that taking temperature readings from one place on Earth instead of from all around the globe is unimportant—such as in the case of the single place readings from the Milan station in Chippewa county that you discuss? It is obviously better to determine long term trends by using the data from numerous stations as well as including homogenized data which takes into regard various non-climate influences, as well as the massive temperature data from satellite readings, which the vast majority of climate scientists have consistently done.

Many of the “facts and figures,” you rely on, seem at best quite questionable. To begin with you state that data from the last 100 years, taken from the Opjorden farm reveal a rise of 1.8 degrees F and also that this rise confirms the results from “various climatic authorities,”and reveals a “clear upward rise over a period of 115 years.” But then you refer to Dr. J Easterbrook who, presented many peer papers at the American Geophysical union meeting in 2008, and whose research has allegedly revealed many warming and cooling trends which have occurred during portions of those last 115 years. However, in conclusion you say that the last period from 1998-2008 is an indication that the past century may “not have been as as catastrophic as predicted by some." And you then claim that a small downward trend ending after those ten years, supports that “strong probability.” So you have taken an upward trend of over 115 years and strongly implied that a recent period of only 10 years may very well, negate it all! How does suggesting that we might soon enter another cooling trend add proof to the contention that global warming as recorded and evaluated by 97% of peer-reviewed and published scientists, is not nearly as dire as they suggest, or may not be happening at all? Ten years of data compared to 115 years of the same, cannot seriously dismiss the overall rise of globally recorded temperatures world wide, nor can it prove that such a rise has little to do with human activities. So why even dwell on such a claim?

I might also note that the 5 differing time periods you use to affirm frequent warming and cooling cycles are very different in length, and can be viewed much differently just by cherry picking data in a different way, i.e. if one includes the first two periods of time as part of one single period—from 1894 to 1945, (a period of 51 years)—one can see that although the ending temperature in 1915 is at, or a little under, 43, at the end of 1945, the final temperature level is listed as at, or a little above, 43. So, if I were to describe a cooling trend by referring to that longer period of time, the evidence would not support the same conclusion—only that temperatures ended a little higher than 43, or at the least, were at the same level as temperatures at the end of 1915. And, if one decides to chop the periods you list, into smaller segments, many more warming and cooling trends can be described within the overall time frame of the periods you (and Dr. Easterbrook) list? I am not saying that all warming and cooling trends must happen over the same amount of time, but your periods range from a high of 32 years, to a low of only ten years between 1998-2009, (depending on which times of year in 1998 and 2009 the measurements are taken from). So the fact that so many different lengths of time are involved just makes me doubt the feasibility of your claims. As you say, the results cannot be proven until after they happen, so why even entertain such a vague theory as if it was extremely significant? I also noticed that the integers you list along the vertical axis of your charts, do not include specific labeling to designate them as either Fahrenheit or Celsius temperatures, and they cover a range of from 36 to 55. But what specific values do those numbers refer to? It seems a bit shoddy of you not to make this clear.

Below is a link to a web article about Donald J. Easterbrook PhD:

http://hot-topic.co.nz/the-incorrigible-easterbrook/

It lists four reasons why Dr. Easterbrook is wrong about global cooling trends and also reveals that he is actually outright dishonest in regards to many of his other claims.

This link for a website article pasted below, also sums up the legitimacy of the Watts study you mention and that much of it is also, just wrong!:

http://www.skepticalscience.com/watts_new_paper_critique.html

“It's worth noting that Peter Thorne of NCDC was interviewed by Andrew Revkin, and discussed three papers which NCDC has recently published (see here, here, here). In the first of those linked papers, they actually conclude that there likely remains a residual cool bias in the adjusted data, and that the adjusted data are consistent with reanalysis data (detailed in the third linked paper). Watts et al. do not address these papers. Ironically Watts responded to that interview by saying that Thorne needs to get out into the real world, but it is Watts et al. who have not accounted for real world effects like TOB, station movement, instrument changes, etc.

In its current form, the Watts paper contains little in the way of useful analysis. There are too many potential sources of bias which are not accounted for, too many apples-to-oranges comparisons, and they cannot draw any conclusions about urban heat influences until their data are homogenized and other non-climate influences are removed.

The primary conclusion of the paper, aside from not being supported by the analysis, is simply implausible. The CONUS surface warming trend proposed by the Watts paper appears to be inconsistent with the satellite observations, and overall global trends in raw data do not differ dramatically from those in the adjusted data. Comparing raw to adjusted data globally shows a rather small difference in long-term trends; far smaller than a factor of two.

The flaws we have identified entirely compromise the conclusions of the paper. Ultimately Watts et al. assume that all adjustments are 'spurious' unless due to urban heat influences, when in fact most of their identified discrepancy likely boil down to important adjustments for instrumental changes, TOB, and other influences they have not accounted for in their analysis. Watts et al. attempt to justify their assumption by asserting "well sited stations are adjusted upward to match the already-adjusted poor stations," but this is simply not how the homogenization process is done.

Fortunately McIntyre has acknowledged that TOB must be considered in their analysis, as has Watts, which is a good start, but they must also account for the other biases noted above in order to draw any valid conclusions about urban heat influences.

In conclusion, Watts et al. of course deserve the right to try to make their case in the peer-reviewed literature, however implausible that case appears to be. Therefore, we hope they will consider addressing the important concerns detailed above before they submit the paper to a journal. Otherwise we suspect the paper will not fare well in the peer review process. With said caveats carefully addressed and the conclusions amended if and where necessary, the paper has the potential to be a useful contribution to the climate science literature.”

I would also like to refer you to the skeptical science website at:

http://www.skepticalscience.com/argument.php

Here you will find 176 common climate myth examined by climate scientists. Two which I suggest you read, are nos. 47 and 118, since both the Little Ice Age in England and the Oregon Institute Petition project are both cited in your paper.

In the case of the little ice age, (no 47) , a number of natural variations likely contributed to abnormal cooling, such as increased volcanic activity, and diminished solar output, both of which can cause cooling.

Likewise, myth 118 examines the dubious methodology that the Oregon Petition project utilized, and the actual relevance of the over 31,000 signatures it contains. You should examine this myth for yourself, but just to put it in perspective, one very significant critique of the Oregon petition is that 32,000 signatures sounds impressive, but only represents 0.3% of the ten million science graduates who posses qualifications that satisfy the terms of the petition. Here is paste with more about myth 47.

“Can We Draw a Conclusion?

In truth, not really. The Little Ice Age remains for the present the subject of speculation. The most likely influence during this period is variable output from the sun combined with pronounced volcanic activity. We know that from the end of the LIA to the 1950s the sun’s output increased. But since WW2 the sun has slowly grown quieter, yet the temperature on Earth has gone up.”

So interestingly although from the end of the LIA the sun's output increased until 1950, but has grown quieter in post WW2 years, one would expect to find that after WW2 temperatures decreased accordingly, but that is just not the case.” And, Mr. Seppa, Are you really not aware that climate scientists have consistently utilized various methods to account for common discrepancies that may result from taking readings from different weather station locations in order to arrive at reliable data? These already include station moves, instrument changes, time of observation, urban island heat biases, and various other inhomogeneities over the last 150 years. Despite your apparent opinion that the tens of thousands of scientists who are now accumulating data, are some kind of incompetent and negligent group that would return to the drawing board if Anthony Watts experiments were replicated, but that is far from the truth. Virtually all the factors which might conceivably produce biased results from ground weather stations, have long ago been considered by climate scientists--who affirm the existence of our present, predominately human caused global warming. However, in many cases additional knowledge from new research, has actually revealed bias on the warmer side. Yet if Mr. watt’s research was actually replicated by a significant number of his peers, you can bet that nearly all knowledgeable climate change researchers, would willingly take notice and adjust their projections in order to make them more accurate. For climate change researchers, Its not merely about being right--it's about accurately evaluating their findings and then drawing logical conclusions from them! Here is a link to a web page on the skeptical science site that explains the issues involved with interpreting weather data:

http://www.skepticalscience.com/print.php?n=2879

Overall your paper is full of important omissions as well as failures to adequately identify the data you site. One example is your mention of the claim that Watt's observations have shown that the new latex paint on shelters caused an increase of .3 degrees F for minimum temperatures, and an .8 F increase for maximum temperatures, but inexplicably you fail to mention what those maximum and minimum temperatures are, or what temperatures they are increases or decreases from? Admittedly the increases and decreases themselves would seem to be the most important, but it's a bit negligent to leave out the actual temperatures themselves, since they might be of obvious importance to those wanting to know all of the specifics. And although you report that Watt's experiments in regards to this supposedly unique study, involved three weather stations, do you expect us to believe that such a small sampling of stations can produce relevant results concerning warning around the globe? Also, after affirming that Watt's experiments involved three different weather reading stations, you make no mention of just where each of them are located. As a person who lives in Superior, WI. I can testify to the fact that frequently, those of us near the lake shore, experience temperatures more than 20 degrees colder than do those living only a few miles inland. So obviously even minor location differences can cause major differences in temperature readings.

Your insistence that climate scientists appear unwilling to to attempt replication of experiments that “refute their basic contentions,” and your implication that “political” motives are driving this supposed refusal, are matters of grave concern. That's because they unfairly imply that scientists are deliberately trying to deceive the public for some unknown end. Nothing could be farther from the truth!

Firstly I would like to ask you what you specifically mean by this allegation, and to provide some of the hows and whys that could motivate learned scientists to seek participation in some sort of massive conspiracy? Rather than just continuing to make this allegation, could you please specifically describe what the goals of this supposed plot are, and how these are going to be accomplished? Many of us would like to know more than just vague allegations involving financial gain, partisan attempts to control the future energy markets of the world, or supposed obedience to pressures from a government that is determined to force their compliance. Tell us instead the whys, whats, and wheres, if you want to remain credible. And if you want to claim that the perfectly feasible assumption that energy companies with very apparent motivations for wanting to avoid jeopardizing the vast wealth they hold in today’s markets, cannot also be credibly implicated as participants in a well contrived conspiracy aimed at discrediting the work of climate scientists, please tell us why?

The projections made by climate scientists concerning today's weather extremes were first advanced in the 1970s and 1980s, and except for some temporary controversy about whether the climate would warm or cool (partly because aerosols were then part of the equation), most past climate scientists projected today’s volatile and extreme weather conditions more than 30 years ago! So if they knew they were advancing a hoax, how then did many of them luck out, and actually live to see their projections validated? Did they use a time machine to visit the post 2000 climate and then go back to 1980 in order to make predictions with use of such extraordinary knowledge? And if the government indeed, has a stake in forcing scientists to provide information beneficial to it, then are these puppet masters conservative Republicans, liberal democrats, or something else in between? And, why have scientists who affirm man's role in today's weather extremes never changed their message, even though several Democrat and Republican governments have since occupied the White House? If those who were under Clinton's thumb never changed their opinions despite the ensuing Presidency of George W. Bush, how could either party be eagerly compliant with the contentions of such a vast conspiracy? Again, give us specifics about how climate researchers intend to benefit by gaining control the future economy. As well as why none of them came forward after Bush's rejection of the Kyoto agreement to expose the liberal coercion that Democrats supposedly forced upon them? And, why do Republicans not also fit the role of conspirators, since many of them align with the desires of big oil, big coal, and big energy companies?

Unlike many climate change deniers, or (contrarians), if you prefer, who have direct connections to think-tanks (funded at least in part), by big oil and big coal special interests, learned scientists who originally made correct predictions thirty or more years ago, aren't likely to live to enjoy the fruits of their supposed treachery, yet deniers who keep insisting on the advancing a reality that promises to usher in even more global temperature increases, along with risking human vulnerability to those extreme weather conditions—like tornadoes, hurricane, droughts, floods, blizzards and so many of the other extremes we are now seeing—presently prosper from their associations with wealthy politically influential sources!

The truth is that climate science has always affirmed that climate change is as old as the earth, and that, specific weather events neither prove nor disprove global warming. They have also long realized that large temperature increases have occurred in previous geological eras, and have always admitted that they do not know all the answers. But, when climate science is described as settled science, this concept primarily refers to the basic fact that global warming is happening, and that we human beings are its major cause. When almost 100 percent of reputable scientists agree on this fact, then that is when one can consider the pertinent issues about this reality to be over and done with. Of course many other unknowns exist, but that does not exclude the fact that, what we now know, is that if we don't take steps to mitigate this potentially disastrous threat, we may be blowing a rare chance to shape Earth's future positively for all of us.

The world has always experienced large climatic changes including pervasive warming temperatures, but what concerns climate scientists of today is the unprecedented RATE of warming, which Is presently more rapid than at any other time in Earth's history. The reason people like me, insist on getting this message across, is that, we are concerned about the future of our children and those of all successive generations. We don't do this for money or political power, but rather to ensure basic survival for all of our fellow human beings. And Mr. Seppa, if you bother to really check out the answers to your unsubstantiated claims, you will understand that not taking positive steps towards preserving the future, is the most devastating failure we will ever face!

Peter W. Johnson

Mr. Seppa’s original letter follows. The original was a pdf file and much of the format has been lost. I will continue to work on it in an attempt to reproduce it more faithfully:

Global Warming (or is it Cooling?) in Milan (Draft)

by Dale Seppa Updated 3-15-2014

If anyone disputes my findings based on the long-term, Milan temperature data please get your own complete data, redo the math, redo the graphs and show me where my error is.  To those that make statements such as; "This is only one place on the earth and when you look at the whole earth it is different"  I urge you to get the unaltered, long-term, data from any other place you wish and see what the trends were there.  The data is easily available at https://weather- warehouse.com/.  Storrs, CT and Superior, WI have records for over a hundred years and I am sure there are many others.  It is important to find locations that have remained in the same place and have not had structures, parking lots etc., built alongside the weather station enclosure.   I believe that the data sets at Weather Warehouse have not been "adjusted" (read "altered") by outside forces but that would be part of your investigation.

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To establish temperature trends at any place on the globe it is necessary to have accurate data over a long period of time.  In Minnesota we are extremely fortunate that there is a source of long-term, continuous, temperature records from rural Milan in Chippewa County.  The Milan records run from the late nineteenth century to the present day.  These records are of great value for people in all walks of life including, of course, professionals that study weather and/or climate.  In the words of Mr. Peter Boulay; “At the State Climatology office, we always use the Milan record as one of the best records in the state for anything that's going on with climate, Since it's always been in one family - it's always been a very good record, a well-behaved record over time, and one we can use for watching climate.”1

The Milan weather observer station is on the Opjorden family farm where a family member has been responsible for the accuracy of the daily data since 1893. The saga began in that year when Mr. O. K. Opjorden first started taking the readings.  Later his daughter Ragna took the responsibility for five years until her brother Torfinn took over and maintained the readings for fifty-seven consecutive years.  He was succeeded by his son Luther, who with the help of his wife Martha and occasional help from a neighbor, has held the reins since 1982.2

Mr. Boulay told me that it is the oldest weather observation station, in Minnesota, that remains in the hands of the original family.  Other reports show it as the oldest one in Minnesota without any qualification.3   It may well be one of less than a dozen, in the entire United States which has been continuously attended by one family for well over a century.

The Opjorden family has won numerous awards from the National Weather Service, including the prestigious Thomas Jefferson Award as well as accolades from scientists and the news media throughout the state and nation.  The last award was, in a way, the most important because in addition to the dedication and work of the Opjorden family it has one requirement that is hard to meet – time.  Excellence and dedication are not enough to win this award; it takes time – a lot of time. The Family Heritage Award is given only to families that have continuously maintained the required records for more than 100 years.4   The award was

presented to Mr. Luther Opjorden, his wife Martha and Ms. Deb Hanson on November 8, 2005 at the Opjorden family farm.

From left with Opie, the dog, are Steve Buan, HPM, NWS Chanhassen, MN; Deb Hanson, Substitute Weather Observer; Pete Boulay, Minnesota DNR Assistant State Climatologist; Craig Edwards, Retired MIC; and Martha and Luther Opjorden, Milan Observers. Photo courtesy of the Milan Standard Watson Journal.

The National Weather Service and indeed the entire state and nation owe a debt of gratitude for this family’s remarkable commitment and the valuable information they have recorded for the benefit of all.5   Without these records it would be difficult, if not impossible, to view trends in temperature and precipitation in the Milan area throughout the years, decades and indeed, with the Opjordens – more than a century.

As only one example of the value of the records, Mr. Boulay, the DNR Assistant State Climatologist, was able to look at the records and determine the average daily temperature has increased at the Opjorden farm about 1.8o Fahrenheit over the past 100 odd years.6   The trend line on the first chart will show how the records substantiate the temperature trend7 mentioned by Mr. Boulay.

1894             Milan             1951          Warming           2008

This trend line seems to tie in nicely with some of the many global warming theories propounded by various climate science “authorities”.  There it is, in red and blue, right before your very eyes; a clear upward rise in a period of a hundred and fifteen years, right there in Milan, Chippewa County, Minnesota.

But, is a rise of less than a couple of degrees Fahrenheit in a period of 115 years adequate confirmation of the multitude of catastrophic anthropogenic global warming claims (CAGW)? Thirty thousand U.S. citizens trained in science; including over 9,000 PhDs, don’t think so.8 One example of these skeptics is Donald J. Easterbrook, Ph.D., who presented one of his many peer-reviewed papers at the American Geophysical Union Fall Meeting in 2008.  Dr.

Easterbrook, Emeritus Professor of Geology at Western Washington University entitled the paper; “Solar Influence on Recurring Global, Decadal, Climate Cycles Recorded by Glacial Fluctuations, Ice Cores, Sea Surface Temperatures, and Historic Measurements Over the Past Millennium.”  His basic contentions are well stated in the abstract so I show them below, exactly as presented therein.

“The Medieval Warm Period and Little Ice Age are well known examples of such climate changes, but in addition, at least 23 periods of climatic warming and cooling have occurred in the past 500 years.  Each period of warming or cooling lasted about 25-30 years (average 27 years).  Two cycles of global warming and two of global cooling have occurred during the past century, and the global cooling that has occurred since 1998 is exactly in phase with the long term pattern.  Global cooling occurred from 1880 to ~1915; global warming occurred from ~1915 to ~1945; global cooling occurred from ~1945-1977; global warming occurred from 1977 to 1998; and global cooling has occurred since 1998.  All of these global climate changes show exceptionally good correlation with solar variation since the Little Ice Age 400 years ago.”

As can be seen from the abstract, Dr. Easterbrook states that we have passed through four periods of “climate change” since 1880 and that we are well into the fifth one.

The five periods shown in the charts below are:

~1894 to ~1915 -  Cooling

~1915 to ~1945 -  Warming

~1945 to ~1977 -  Cooling

~1977 to ~1998 -  Warming

~1998 to ~2009 -  Cooling

The explanation for this cooling/warming phenomenon lies in the title of his paper and is detailed in the paper itself so I will comment only on the trends as shown by the Milan records. All charts used shown below are based on the mean daily temperatures from the Milan records as retained at the NOAA Midwestern Regional Climate Center9 and, in my opinion, seem to substantiate the conclusions of Dr. Easterbrook.10   If you look carefully at the following charts you will see a clear correlation of the trend lines with the periods outlined by him.

1894             Milan            1904              Cooling          1915

1915             Milan             1930          Warming           1945

1945             Milan             1961          Cooling             1977

1977             Milan             1988          Warming           1998

1998             Milan             2003          Cooling             2008

The trend line on the 1998–2008 chart shows quite clearly there is a strong probability that the “global warming” the past century may not have been the catastrophe predicted by some.  It would appear, looking at Easterbrook’s paper and the temperature trends from Milan, that a cycle of global cooling started about 1998 and that its effects will be obvious in the not too distant future.  Obviously, these cycles span lengthy periods and therefore are not provable until after they happen. Climate changes, and always has, for billions of years.                                                                                        But, be that as it may, this is not the end of the story of global warming in Milan or for that matter, for the entire world.

Anthony Watts has been a meteorologist for thirty years and in addition to the tens of thousands of hours he has devoted to his profession, his spare time is spent as an anthropogenic global warming skeptic.  He is not alone in this endeavor as he has a band of loyal followers that give much of their free time to acquire data for him.  This is on an unpaid volunteer basis, as they pursue their self-appointed quest for truth.

Watts recently published a 31 page paper entitled; “Is The U.S. Surface Temperature Record Reliable”.  There is too much in his work to discuss herein but one of his principal points is that after about 1979 the U.S. Weather Service made a change in the specification for the paint used for the instrument shelters found at the volunteer weather stations in the United States.  These shelters house the thermometers and other instruments used at the weather station.  His contention is that the change in paint caused a significant rise in the recorded temperatures.

While "climate scientists" often rely on proxies and computer models, Watts uses experimentation and observation, with actual temperatures from real thermometers to make his determinations.  He purchased three of the weather-station, instrument shelters and left one with bare wood as a control, painted one with the whitewash that they used pre-1979, and painted the third with the post-1979 latex paint.  Specifications given for the thermometers used in the experiment appear to be state of the art.

His observations showed that the new latex paint on the shelters caused an increase of .3o F for minimum temperatures and an .8o F increase for maximum temperatures.  In his words; “This is a big difference, especially when we consider that the concern over anthropogenic global warming was triggered by what these stations reported was an increase of about 1.2o F over the entire twentieth century.”  If his experiment is replicated and proven to be valid I suspect there will be a few climate scientists going back to the drawing board.  Unfortunately, it seems, to me, that many “climate scientists” appear unwilling to attempt replication of experiments that refute their basic contentions.  But that is a political/financial phenomenon that should not be touched on in a paper of this nature.

Is the article produced by Watts the definitive document that we should use to determine the course of climate science?  Certainly not - nor is the peer reviewed paper of Easterbrook sufficient.  We cannot even say with any certainty what temperatures were in Milan 200 years ago let alone guess world temperatures 200 years in the future.  I believe it would be far more pertinent to solve the climate mysteries of the past such as the Medieval Warm Period and the Little Ice Age before we delve too deeply into the climate prediction business, particularly when the “climate models” from the 70s, 80s, 90s and early part of the 20th century have been proven woefully inaccurate.                 Can we, as a nation, afford to spend trillions of dollars of taxpayer funds based on hypothetical numbers, failed predictions and unproven speculation?

Global Warming is not “settled science”.  Anyone that says it is “settled” does not understand enough about science to make comments let alone scientific decisions. “Science is never settled, in any field, because it is the nature of science to theorize and test and then prove or disprove…

– continuously!”11   How can “climate science” be a “settled science” when thirty thousand

people, trained in science, were willing to sign a petition to the contrary? 8 Any reader with basic research skills can easily find hundreds of peer reviewed papers, as well as thousands of non- peer reviewed articles that cast doubt on, or completely refute one or more of the contentions of catastrophic anthropogenic global warming (CAGW) fanatics.

What should we believe when we are told; “The Science is settled” – no more questions allowed?  There is no doubt what the answer would be if we could ask; “Galileo, Newton and Einstein, to name a few of science’s luminaries who dissented from popular views and paved new paths toward understanding the mysteries of the universe.”

/30

Note Jan 8, 2014 -  If the readings for 2009 thru 2014 were added and the graphs updated I believe the results would be even more dramatic.  I understand that even the "climate scientists" at the IPCC have now realized that world temperatures have fallen for eighteen years.  At least a few qualified scientists have expressed the possibility that we are entering a new Maunder Minimum although I would imagine they will name if for someone else.  Mann Minimum might be a cool name.

1 Minnesota Farm Guide, October 26, 2007

2 Minnesota Farm Guide, October 26, 2007

3 Duluth News Tribune, January 7, 2010.  Mr. Peter Boulay just wrote me 2/08/2010 and said it is the longest still in one family.

4 National Weather Service Instruction 10-1314, November 3, 2008

5 The National Cooperative Observer, Winter, 2007

6 Minnesota Farm Guide, October 26, 2007

7 Trend lines will vary depending on which  reading or calculated temperature is used.  Some of the temperatures recorded or calculated are highest, lowest, highest low, daily mean, etc., etc.

8 The petition project is found at www.petitionproject.org.  There are many sites that laud and an equal or greater number that decry this project.  Nevertheless, I have personally checked the names of dozens of the Minnesota signers and they have, as they said, degrees in science including atmospheric  scientists, physicists, geographers, agronomists, medical doctors and others.

9   I have used derived numbers from the “Mean Daily Temperature.   There are many different temperatures recorded and calculated.  For daily records this includes (among others) lowest, highest, warmest minimum,

coldest maximum, average minimum and the mean temperatures as calculated from some of the other temperatures.  At any rate it seems as though no matter which data set you use the trends are about the same.   10 Although the Opjorden data is as good as it gets there were a few readings that are missing in the Mean Daily data set that I used.  Out of 1368 readings there were 6 missing.  For these “Not Recorded” readings I substituted a number.  I was extremely cautious when I did this.  I used a process of seeking the data elsewhere,

comparison with previous and following years and common sense.  I am satisfied in my own mind that these few substituted readings will be accepted by anyone with some basic mathematical knowledge..

11  http://www.rathergate.com/?p=4273