2015-01-30

By Paul Homewood

Bill Illis adds some interesting fuel to the debate over temperature adjustments.

As many of you may be aware, I first became aware of this issue in 2012, with the adjustments made in Iceland, such as this one at Reykjavik.



http://data.giss.nasa.gov/cgi-bin/gistemp/show_station.cgi?id=620040300000&dt=1&ds=1

http://data.giss.nasa.gov/cgi-bin/gistemp/show_station.cgi?id=620040300000&dt=1&ds=12

As with all the other sites in Iceland, the GHCN adjustment had effectively removed the inconvenient warm period around 1940, when temperatures were just as high as they have been in the last decades.

In addition, and as a direct result, they also eliminated the extremely cold years of the 1960’s and 70’s, which were so bad that the Icelanders themselves christened them the “sea ice years”, as their Met Office reports:

The 20th century warm period that started in the 1920s ended very abruptly in 1965. It can be divided into three sub-periods, a very warm one to 1942, a colder interval during 1943 to 1952, but it was decisively warm during 1953 to 1964.

The cold period 1965 to 1995 also included a few sub-periods. The so called "sea ice years" 1965 to 1971, a slightly warmer period 1972 till 1978, a very cold interval during 1979 to 1986, but thereafter it became gradually warmer, the last cold year in the sequence being 1995. Since then it has been warm, the warmth culminating in 2002 to 2003. Generally the description above refers to the whole country, but there are slightly diverging details, depending on the source of the cold air.

Many subsequent studies have investigated the cause of the sudden drop in temperature during those years, which were known as “The Great Salinity Anomaly – 1968 to 1982”.

Quite clearly, then, this cold period existed and caused real problems. It was not a measurement error, or a station move, that needed to be “homogenised” out of existence.

However, Bill kept a record of the GHCN adjustment page for Reykjavik, as it was published in February 2014. He compares this with the January 17th and January 29th versions for this year.

The charts can be better viewed by clicking on the links.



21st Feb 2014

http://s17.postimg.org/v8rjasxfj/Reykjavik_62004030000.gif



17th January 2015

http://s12.postimg.org/3zv0kfn0d/Reykjovik_2015_62004030000.gif

29th January 2015

http://s10.postimg.org/z3og0cwhl/Reykjovik_Jan29_2015_62004030000.gif

If you compare the trend line of the middle graph, on the right (i.e the yellowy thing), there is more than 2C of warming over the full period since 1900. Yet last February there was a lot less than 2C.

The latest trend is even greater than the one GHCN came up with a fortnight ago! In particular, there has been a step up in the warming adjustment during the 1970’s. ( Last year’s version kept the same figure through from 1970.

What this boils down to is that GHCN are making things up as they go along.

They have adjusted historic temperatures, supposedly because they have found anomalies with them, which they assume are wrong. But worse than this is that having adjusted them once, they go back and adjust them again and again.

This makes a mockery of their claim that their homogenisation procedures produce accurate temperature assessments, if they keep having to alter their results.

Apparently, the latest defence of these adjustments from the likes of Kevin Cowton is that they are “calibrating data”. This choice of words is no doubt designed to persuade people that what they are doing is somehow legitimate and accurate. Oxford Dictionary gives this definition of “calibrate”:-

Correlate the readings of (an instrument) with those of a standard in order to check the instrument’s accuracy.

This, most decidedly, is what they are not doing, as they have no means of knowing what the “standard” is. All they are doing is changing the temperature records of places like Reykjavik, without any evidence that they are wrong, and making them match those of other places, maybe hundreds of miles away, on the assumption that:

a) There is any connection or correlation between them

b) That the other places have accurate records.

The fact that they have now had three different versions of Reykjavik’s record in the last year clearly proves that their “calibration” has no accuracy, and therefore no value.

Meanwhile, the only people who can give a full and proper explanation of what they have done with the Paraguayan stations, and why, are NOAA themselves. I requested this information a week ago, but apart from a standard confirmation of receipt of my request, have had no further response.

I also did the same in 2012, with the Icelandic examples, chased many times, and received many assurances that my request would be answered. Unsurprisingly, NOAA never did come up with an answer.

I won’t be holding my breath this time either.

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