Fire Return Interval Departure (Frid) - Mean Percent - Since 1970

Percent FRID (PFRID) quantifies the extent in percentage to which recent fires (i.e., since 1970) are burning at frequencies similar to those that occurred prior to Euro-American settlement, with the mean reference FRI as the basis for comparison. Mean PFRID measures the departure of current FRI from reference mean FRI in percent

Data and Resources

Additional Info

Field Value
Version Version 5.0
Last Updated March 28, 2025, 08:36 (UTC)
Created March 7, 2025, 07:52 (UTC)
category /Fire Dynamics/Functional Fire/Fire Return Interval Departure (FRID)
collection_name California Landscape Metrics
creation_method The current FRI is calculated by dividing the number of years in the fire record (e.g., 2019-1970=49 years inclusive) by the number of fires occurring between 1970 and the current year in a given polygon plus one (CurrentFRI = Number of years/Number of fires +1). The mean reference FRI is an approximation of how often, on average, a given PFR likely burned in the three or four centuries prior to significant Euro-American settlement. This measure does not return to zero when a fire occurs, unlike FRID values used in some other analyses (e.g., NPS FRID Index).
data_units Percent
data_vintage 2022. Includes disturbances through the end of 2022.
date_updated August 2024
element Functional Fire
encoding utf8
file_name FRID_MeanPrct_19702022_202401_T1_v5
format GeoTiff
harvest_object_id 9cbeb440-30d4-4097-a443-addd35bccd3c
harvest_source_id a2637971-af12-457f-ae4a-831d2202a539
harvest_source_title WIFIRE Commons
maximum_value 79.2
metric_definition_and_relevance Percent FRID (PFRID) quantifies the extent in percentage to which recent fires (i.e., since 1970) are burning at frequencies similar to those that occurred prior to Euro-American settlement, with the mean reference FRI as the basis for comparison. Mean PFRID measures the departure of current FRI from reference mean FRI in percent
minimum_value -99.2
pillar Fire Dynamics
spatial {"type": "Polygon", "coordinates": [[[-124.5090833859125, 32.4242698701859], [-113.49380570277376, 32.4242698701859], [-113.49380570277376, 42.1119747450123], [-124.5090833859125, 42.1119747450123], [-124.5090833859125, 32.4242698701859]]]}
sub_element Fire Return Interval Departure (FRID)
tier 1