You are here

Tree Ring

Diagram of tree-rings                   Extending a chronology through crossdating                   Bristlecone pine

The International Tree-Ring Data Bank (ITRDB) is the world's largest archive of tree ring data, managed by NCDC's Paleoclimatology Branch and the World Data Center for Paleoclimatology. The ITRDB includes raw ring width, wood density, isotope measurements, and site growth index chronologies. Over 3,000 sites on six continents are included. Reconstructed climate parameters are also available for some areas.

Obtaining Data at the World Data Center   

Search Datasets

  • Tree Ring Search Engine
    ​Search through tree ring studies using Investigator, Title, Location Name, Tree Species, and Latitude/Longitude bounds.
  • Google Earth Map
    Locate and download tree ring studies using a Google Earth map interface. Google Earth must be installed to use this search tool.
  • Search All Paleoclimatology Data
    A free text search of our entire study archive.

Browse Datasets

Contributing Data                             

Investigators who wish to contribute their data to the ITRDB can find information on contributing below. Data and study description information can be contributed via the contribution form or by emailing data to

Other Data Archives

Additional sources for data and information on tree rings.