Tucson format
Tucson format or decadal format or rwl format is one of the most common formats for ring width data storing. It is the standard format for ITRDB. It is a text file format. Different extensions are used, such as .rwl, .crn, .tuc and .dec. (.crn is used for derivate chronologies). The name comes from the city Tucson in Arizona.
A Tucson file consists of three lines of meta data followed by an undefined number of data lines (and cores). A data line consist of the core identity (max 8 letters or digits), year of the oldest measurement of the line (4 digits)[1] ring width data, up to ten rings per line. Measurement data is either given with 3 or 4 digits according to resolution. Except the first and last line of each core there are measurements for one decade per line. After the youngest ring there is a "999" as stop mark. Missing data mark is -999.
PMkr12b 1781 120 87 69 122 108 85 125 114 77 PMkr12b 1790 134 131 114 97 117 49 69 100 123 89 PMkr12b 1800 137 89 -999 79 44 38 62 99 68 26 PMkr12b 1810 27 43 51 57 36 999
An example of three digit resolution sample which covers the timespan AD 1781-1814, with a missing ring for AD 1802 (-999). The width of AD 1781 (the first year) annual ring is 1.20 mm and for 1782 AD 0.87 mm.
CDendro interpretation
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See also CDendro naming standard
Limitations of the Tucson format
Notes
- ↑ If 5 digits are needed for the year, ie older than -999, the identity can not be more than 7 letters.