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Tree Ring

The World Data Service for Paleoclimatology manages the International Tree-Ring Data Bank (ITRDB), the world's largest public archive of tree ring data.  Oversight is provided by the ITRDB Advisory Committee. The ITRDB includes raw ring width, wood density, isotope measurements, and site growth index chronologies from more than 5,000 sites on six continents. Reconstructed climate parameters are also available for some areas.

Tree Ring image

Accessing Data at the World Data Service for Paleoclimatology

Search Tree Ring Data

Search through tree ring studies using Investigator, Title, Location Name, Tree Species, and Latitude/Longitude bounds.

Launch Tree Ring Data Search

Search All Paleoclimatology Data

Access a free text search of our entire archive.

Launch Paleo Data Search

Interactive Map

Select study locations by region, proximity to a point, or text-based attributes.

Launch Interactive Map

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.

Download .KMZ File

NCEI Paleo Web Service

Use the NCEI Paleo Web Service to access tree ring study metadata records.

API Documentation

Contributing Data

To contribute to the ITRDB, review our instructions for contributing data. Prospective data providers can email to submit data and study description information in decadal format. If the data files do not include header information, please also complete the metadata portion of our data contribution template (available at the link below) and email template along with the decadal format data files.

Other Resources

Additional sources for data and information on tree rings.