PaleoEvent Data Standards for Dendrochronology Workshop


Registration deadline: 30 April 2017
Workshop dates: 10-14 September 2017

Registration form


We announce a PAGES sponsored workshop from the 10-14 September 2017 at the Manitou Experimental Forest (MEF), Woodland Park, Colorado to develop a new data management framework applicable to fire history and all other tree-ring paleoevent data.  This framework will provide for robust metadata records and be current with leading data management standards. 

This is an open workshop with a maximum of 15 participants.  Please register your interest by April 30, 2017.  PAGES will review the set of registrants and make final decisions about participants to ensure diversity. Some travel support is available.


Many factors influence tree growth.  Some, like soil type, are essentially unvarying in the context of a tree’s lifespan.  Climate varies annually and its influence on tree growth is the focus of many dendrochronological studies.  Over the lifespan of a tree many events can happen and indicators related to the events are recorded in tree rings:  fires cause scars, earth movements tilt trees and cause eccentric growth, late frosts cause frost rings, and insect outbreaks can suppress growth.  Collectively a series of event indicators are paleoevent chronologies.  Perhaps the most well-known paleoevent chronologies are fire histories based on fire-scarred trees.  

Data collection creates the need for data management.  Good data management should fulfill two goals:  to facilitate data storage and analysis for the investigator and to archive the data.  Fire history data are often stored in FHX(2) text files.  (Investigators sometimes use the FHX format to record other events, like insect outbreaks.)  The public database for fire history data is the International Multiproxy Paleofire Database (the IMPD, hosted by NOAA); it uses the FHX format.  The FHX format has limitations: metadata is not mandatory or standardized; managers at the IMPD store metadata in an auxiliary database.  Metadata is associated with the site, not samples, and only one indicator per year per sample can be recorded.  For example, a fire might be indicated by a scar positioned in the early earlywood and the appearance of traumatic resin ducts, following by a growth release.  In FHX format, the only information that could be recorded would be that there was a scar in the early earlywood.  

The need to define various indicators of events in tree rings requires the thoughtful input of specialists in several disciplines.  Indicators of defoliating insects include light rings (no latewood) and narrow growth.  Events that eliminate competing trees result in growth releases and regeneration of new trees.  Tree decapitation can indicate rockfall impact close to the ground.  In certain situations it will be impossible to discern which specific event occurred but this process of characterizing the indicators of events will both describe and enumerate them.

In this workshop we propose to begin a new data management framework for fire history and other tree-ring paleoevent chronologies.  Data in FHX format were first analyzed in the FHX2 software (2) and more recently in FHAES(3).  FHAES uses the FHX format but also uses the Tree Ring Data Standard (TRiDaS)(4) through the TRiCYCLE dendro converter library(5).  The new framework will be based on TRiDaS(5) and provide for robust metadata records(6), the capacity to record multiple event types, and more than one attribute per year per sample.

Workshop goals

We will build a new data management framework applicable to all dendrochronological paleo-event data, providing for robust metadata records, and current with leading data management standards.  The work will be collaborative, using a crowd-curation approach to gather content with an international, interdisciplinary group.  In the workshop we will conduct charrettes to develop data standards, metadata standards, and a common terminology, i.e. controlled vocabularies. 

We will outline workshop products, create timelines, and make writing assignments for products.  Workshop results will be used to guide the development of both TRiDaS and Linked Paleo Data (LiPD)(6).  The organizers have discussed using it as a new paleo-event data archive with managers at the NOAA World Data Service for Paleoclimatology; a representative will attend the workshop. 

Who should participate?

We seek scientists or professionals with diverse experience in event-related tree-ring studies (entomology, fire, geosciences, meteorology, and hydrology) that have applied evidence of events (wood anatomy, scarring, and growth change) or have data management skills (controlled vocabularies, linked data, XML schema, etc.).  We encourage early-career scientists and those residing in developing countries to participate. 

Expected products

  • Workshop report for PAGES
  • Extension to the TRiDaS data model to accurately describe paleoevent data
  • Manuscript for peer-reviewed journal; description of this framework and a potential new archive
  • The ultimate goal of this work is the creation of a public archive for dendrochronological paleoevent data, potentially via NOAA NCEI.


Elaine Kennedy Sutherland ( - USDA Forest Service, Rocky Mountain Research Station)
Peter Brewer ( - University of Arizona, Laboratory of Tree-Ring Research).


(1) DeSantis RD et al. 2013. Ag. For. Met. 178:120-128
(2) Grissino-Mayer HD. 2001. Tree-Ring Res. 57:115-124
(3) Brewer PW et al. 2016. Fire History Analysis and Exploration System, 2.0.2
(4) Jansma E et al. 2010. Dendrochronologia 28:99-130
(5) Brewer PW et al. 2011. Tree-Ring Res. 67:135-144

(6) Emile-Geay J et al. 2016. PAGES Magazine 24:47