Danish National Museum

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Dendrochronological reports by the Danish National Museum in Copenhagen are published continuously. They sometimes include measurement data, either as list of numbers or as diagrams, from which data of often good quality is possible to retrieve with CooRecorder). Especially many of the Norwegian reports often contains data, see SNorwQ.

The Museum also has published the westDK oak chronology for Jylland and Fyn (AD 200-1986).


How to retrieve data from the curve diagrams

The reports are in PDF-format and before the diagrams can be read with CooRecorder the pages containing curve diagrams has to be converted into jpg-format. This conversion may be done with e.g GSview[1]. Using a high resolution is recommended, e.g. 600 dpi.

The curve diagrams are logarithmic. A few of them have two labeled levels at the y-axis, e.g. 20 and 200. In those cases the calibration double point label should be "SCALE 0.2 2.0 Log" (CooRecorder operates with mm but the y-axis labels in the report are in 1/100 mm). Always put the first double point (1:1) at the lower mark and the second (1:2) at the higher.

In most cases, however, only the label "1" is given, which is difficult to interpret. Fortunately there are a few reports which contain the same data in table form and as curve diagram[2]. Those makes it possible to find out an optimal label useful for all curve diagrams of this type. The label should be "SCALE 0.52 1 Log", and the first double point (1:1) at the lower "bottom mark" of the y-axis and the second (1:2) at the mark labeled "1".


  1. Wikipedia (English) article about GSview
  2. NNU report 2006:3 (A8614) and NNU report 2006:8 (A8627)