| Use of the word "trick" was not intended to imply any deception TegenArgument1 #41348 The word "trick" is commonly used in scientific literature to signify a clever method or approach as opposed to a means to deceive. |
Climatic Research Unit statement:
"One particular, illegally obtained, email relates to the preparation of a figure for the WMO Statement on the Status of the Global Climate in 1999. This email referred to a “trick” of adding recent instrumental data to the end of temperature reconstructions that were based on proxy data. The requirement for the WMO Statement was for up-to-date evidence showing how temperatures may have changed over the last 1000 years. To produce temperature series that were completely up-to-date (i.e. through to 1999) it was necessary to combine the temperature reconstructions with the instrumental record, because the temperature reconstructions from proxy data ended many years earlier whereas the instrumental record is updated every month. The use of the word “trick” was not intended to imply any deception.
Phil Jones comments further: “One of the three temperature reconstructions was based entirely on a particular set of tree-ring data that shows a strong correlation with temperature from the 19th century through to the mid-20th century, but does not show a realistic trend of temperature after 1960. This is well known and is called the ‘decline’ or ‘divergence’. The use of the term ‘hiding the decline’ was in an email written in haste. CRU has not sought to hide the decline. Indeed, CRU has published a number of articles that both illustrate, and discuss the implications of, this recent tree-ring decline, including the article that is listed in the legend of the WMO Statement figure. It is because of this trend in these tree-ring data that we know does not represent temperature change that I only show this series up to 1960 in the WMO Statement.”
The ‘decline’ in this set of tree-ring data should not be taken to mean that there is any problem with the instrumental temperature data. As for the tree-ring decline, various manifestations of this phenomenon have been discussed by numerous authors, and its implications are clearly signposted in Chapter 6 of the IPCC AR4 report.
Included here is a copy of the figure used in the WMO statement, together with an alternative version where the climate reconstructions and the instrumental temperatures are shown separately."
"The WMO1999 figure (top) with climate reconstructions and instrumental temperatures merged, and a version (bottom) with the climate reconstructions (coloured) and instrumental temperatures (annual & summer in black) shown separately."
|