NOAA NCEI Paleoclimatology / International Tree-Ring Data Bank (ITRDB) Selected raw ring-width measurement files Mirror snapshot fetched 2026-05 from: https://www.ncei.noaa.gov/pub/data/paleo/treering/measurements/ Citation -------- Cite the original contributor identified in each .rwl file header. The ITRDB data bank itself should be cited as: Grissino-Mayer, H.D. and Fritts, H.C. (1997). "The International Tree-Ring Data Bank: an enhanced global database serving the global scientific community." The Holocene 7(2): 235-238. NOAA / NCEI Paleoclimatology Program -- International Tree-Ring Data Bank. https://www.ncei.noaa.gov/products/paleoclimatology/tree-ring File format ----------- All files are in the standard Tucson decadal format (.rwl). Each line encodes one decade of measurements for a single radius: v1 v2 v3 v4 v5 v6 v7 v8 v9 v10 Measurements are integer values, units 0.01 mm or 0.001 mm depending on the contributor instrument calibration (the header line declares the precision). The terminator value 999 (or -9999 in some series) marks the inner end of a radius. Series included --------------- ak001.rwl Alaska -- white spruce (Picea glauca), Sheenjek River ak068.rwl Alaska -- white spruce, Firth River ca534.rwl California -- giant sequoia (Sequoiadendron giganteum) ca535.rwl California -- Great Basin bristlecone pine, Methuselah Walk nm572.rwl New Mexico -- Douglas-fir, El Malpais swit200.rwl Switzerland -- larch (Larix decidua), Lotschental Valley wa066.rwl Washington -- mountain hemlock, Mount Rainier nepa001.rwl Nepal -- Himalayan fir (Abies spectabilis) Selection criteria ------------------ Series were chosen by hand for teaching use: long chronologies, well- documented crossdating, and broad coverage of the conventional Northern Hemisphere dendroclimate latitudes. This is not a representative sample of the ITRDB.