First, we would like to thank the wildland fire advisory group. Their wisdom and guidance helped us build the dataset as it currently exists. Currently, there are multiple, freely available fire datasets that identify wildfire and prescribed fire burned areas across the United States. However, these datasets are all limited in some way. Their time periods could cover only a couple of decades or they may have stopped collecting data many years ago. Their spatial footprints may be limited to a specific geographic area or agency. Their attribute data may be limited to nothing more than a polygon and a year. None of the existing datasets provides a comprehensive picture of fires that have burned throughout the last few centuries. Our dataset uses these existing layers and utilizes a series of both manual processes and ArcGIS Python (arcpy) scripts to merge these existing datasets into a single dataset that encompasses the known wildfires and prescribed fires within the United States and certain territories. Forty different fire layers were utilized in this dataset. First, these datasets were ranked by order of observed quality (Tiers). The datasets were given a common set of attribute fields and as many of these fields were populated as possible within each dataset. All fire layers were then merged together (the merged dataset) by their common attributes to created a merged dataset containing all fire polygons. Polygons were then processed in order of Tier (1-8) so that overlapping polygons in the same year and Tier were dissolved together. Overlapping polygons in subsequent Tiers were removed from the dataset. Attributes from the original datasets of all intersecting polygons in the same year across all Tiers were also merged so that all attributes from all Tiers were included, but only the polygons from the highest ranking Tier were dissolved to form the fire polygon. The resulting product (the combined dataset) has only one fire per year in a given area with one set of attributes. While it combines wildfire data from 40 wildfire layers and therefore has more complete information on wildfires than the datasets that went into it, this dataset has also has its own set of limitations. Please see the Data Quality attributes within the metadata record for additional information on this dataset's limitations. Overall, we believe this dataset is designed be to a comprehensive collection of fire boundaries within the United States and provides a more thorough and complete picture of fires across the United States when compared to the datasets that went into it.

First, we would like to thank the wildland fire advisory group. Their wisdom and guidance helped us build the dataset as it currently exists. This dataset is comprised of two different zip files. Zip File 1: The data within this zip file are composed of two wildland fire datasets. (1) A merged dataset consisting of 40 different wildfire and prescribed fire layers. The original 40 layers were all freely obtained from the internet or provided to the authors free of charge with permission to use them. The merged layers were altered to contain a consistent set of attributes including names, IDs, and dates. This raw merged dataset contains all original polygons many of which are duplicates of the same fire. This dataset also contains all the errors, inconsistencies, and other issues that caused some of the data to be excluded from the combined dataset. Care should be used when working with this dataset as individual records may contain errors that can be more easily identified in the combined dataset. (2) A combined wildland fire polygon dataset composed of both wildfires and prescribed fires ranging in years from mid 1800s to the present that was created by merging and dissolving fire information from 40 different original wildfire datasets to create one of the most comprehensive wildfire datasets available. Attributes describing fires that were reported in the various sources are also merged, including fire names, fire codes, fire IDs, fire dates, fire causes. Zip File 2: The fire polygons were turned into 30 meter rasters representing various summary counts: (a) count of all wildland fires that burned a pixel, (b) count of wildfires that burned a pixel, (c) the first year a wildfire burned a pixel, (d) the most recent year a wildfire burned a pixel, and (e) count of prescribed fires that burned a pixel.

First, we would like to thank the wildland fire advisory group. Their wisdom and guidance helped us build the dataset as it currently exists. This dataset is comprised of two different zip files. Zip File 1: The data within this zip file are composed of two wildland fire datasets. (1) A merged dataset consisting of 40 different wildfire and prescribed fire layers. The original 40 layers were all freely obtained from the internet or provided to the authors free of charge with permission to use them. The merged layers were altered to contain a consistent set of attributes including names, IDs, and dates. This raw merged dataset contains all original polygons many of which are duplicates of the same fire. This dataset also contains all the errors, inconsistencies, and other issues that caused some of the data to be excluded from the combined dataset. Care should be used when working with this dataset as individual records may contain errors that can be more easily identified in the combined dataset. (2) A combined wildland fire polygon dataset composed of both wildfires and prescribed fires ranging in years from mid 1800s to the present that was created by merging and dissolving fire information from 40 different original wildfire datasets to create one of the most comprehensive wildfire datasets available. Attributes describing fires that were reported in the various sources are also merged, including fire names, fire codes, fire IDs, fire dates, fire causes. Zip File 2: The fire polygons were turned into 30 meter rasters representing various summary counts: (a) count of all wildland fires that burned a pixel, (b) count of wildfires that burned a pixel, (c) the first year a wildfire burned a pixel, (d) the most recent year a wildfire burned a pixel, and (e) count of prescribed fires that burned a pixel.

First, we would like to thank the wildland fire advisory group. Their wisdom and guidance helped us build the dataset as it currently exists. Currently, there are multiple, freely available wildland fire datasets that identify wildfire and prescribed fire areas across the United States. However, these datasets are all limited in some way. Time periods, spatial extents, attributes, and maintenance for these datasets are highly variable, and none of the existing datasets provide a comprehensive picture of wildfires that have burned since the 1800s. Utilizing a series of both manual processes and ArcGIS Python (arcpy) scripts, we merged 40 of these disparate datasets into a single dataset that encompasses the known wildfires within the United States from the 1800s to the present. These datasets were ranked by order of observed quality, and overlapping polygons in the same year were used individually or dissolved together with other polygons based on ranked quality (see individual steps in the polygon metadata for full details). The fire polygons were turned into 30 meter rasters representing various summary counts: (a) count of all wildland fires that burned a pixel, (b) count of wildfires that burned a pixel, (c) the first year a wildfire burned a pixel, (d) the most recent year a wildfire burned a pixel, and (e) count of prescribed fires that burned a pixel.

First, we would like to thank the wildland fire advisory group. Their wisdom and guidance helped us build the dataset as it currently exists. Currently, there are multiple, freely available wildland fire datasets that identify wildfire and prescribed fire areas across the United States. However, these datasets are all limited in some way. Time periods, spatial extents, attributes, and maintenance for these datasets are highly variable, and none of the existing datasets provide a comprehensive picture of wildfires that have burned since the 1800s. Utilizing a series of both manual processes and ArcGIS Python (arcpy) scripts, we merged 40 of these disparate datasets into a single dataset that encompasses the known wildfires within the United States from the 1800s to the present. These datasets were ranked by order of observed quality, and overlapping polygons in the same year were used individually or dissolved together with other polygons based on ranked quality (see individual steps in the polygon metadata for full details). The fire polygons were turned into 30 meter rasters representing various summary counts: (a) count of all wildland fires that burned a pixel, (b) count of wildfires that burned a pixel, (c) the first year a wildfire burned a pixel, (d) the most recent year a wildfire burned a pixel, and (e) count of prescribed fires that burned a pixel.

This dataset is comprised of four different zip files. Zip File 1: A combined wildfire polygon dataset ranging in years from 1878-2019 (142 years) that was created by merging and dissolving fire information from 12 different original wildfire datasets to create one of the most comprehensive wildfire datasets available. Attributes describing fires that were reported in the various source data, including fire name, fire code, ignition date, controlled date, containment date, and fire cause, were included in this product’s attribute table. Zip Files 2-4: The fire polygons were turned into 30 meter rasters with the values representing area burned in each year (128 yearly rasters total, as some years in the 1800s had no fires recorded). Three rasters were calculated from the yearly rasters: (a) their yearly values were turned to 1 and these values were summed to create a count of the number of times burned, (b) the first time a pixel burned was selected to create a first year burned raster, and (c) the last time a pixel burned was selected to create a most recent year burned raster. These calculations were done for the contiguous US, Alaska, and Hawaii separately in order to reduce file size and download time. Each of the zipped files contains the three rasters for one of the following locations: contiguous US, Alaska, and Hawaii.

This dataset is comprised of four different zip files. Zip File 1: A combined wildfire polygon dataset ranging in years from 1878-2019 (142 years) that was created by merging and dissolving fire information from 12 different original wildfire datasets to create one of the most comprehensive wildfire datasets available. Attributes describing fires that were reported in the various source data, including fire name, fire code, ignition date, controlled date, containment date, and fire cause, were included in this product’s attribute table. Zip Files 2-4: The fire polygons were turned into 30 meter rasters with the values representing area burned in each year (128 yearly rasters total, as some years in the 1800s had no fires recorded). Three rasters were calculated from the yearly rasters: (a) their yearly values were turned to 1 and these values were summed to create a count of the number of times burned, (b) the first time a pixel burned was selected to create a first year burned raster, and (c) the last time a pixel burned was selected to create a most recent year burned raster. These calculations were done for the contiguous US, Alaska, and Hawaii separately in order to reduce file size and download time. Each of the zipped files contains the three rasters for one of the following locations: contiguous US, Alaska, and Hawaii.

Wildland fire event polygons for 2004-2017 reconciled in SmartFire 2 for the EPA Air Quality Times Series (EQUATES) modeling project (https://doi.org/10.1016/j.dib.2023.109022). These event polygons represent a combination of properties from a collection of remotely sensed and ground-based fire activity datasets. The primary underlying fire activity datasets for the fire event polygons are the Hazard Mapping System (HMS) remote sense fire product (https://www.ospo.noaa.gov/Products/land/hms.html), SIT-ICS/209 Incident Reports (https://www.wildfire.gov/application/sit209), GeoMAC Fire Event polygons (https://data-nifc.opendata.arcgis.com/datasets/nifc::historic-perimeters-combined-2000-2018-geomac/about), and the Monitoring Trends in Burn Severity (MTBS) burn scar event perimeters (https://www.mtbs.gov/direct-download). This dataset includes events identified as over wildland and does not contain biomass burning events over agricultural areas, such as crop residue field burns. Additionally, certain grass fires, such as the annual prescribed fires in the Flint Hills region, have been removed for inclusion in a separate processing stream. Some minor updates have been made to the dataset since the publishing of the EQUATES emission inventories including removal of known errors related to issues in the underlying activity. This dataset is associated with the following publication: Beidler, J., G. Pouliot, and K. Foley. 2004-2017 Geospatial Dataset of Wild and Prescribed Fire Activity Over the Conterminous United States. Data in Brief. Elsevier B.V., Amsterdam, NETHERLANDS, 56: 110856, (2024).

The Fire Regime Groups layer characterizes the presumed historical fire regimes within landscapes based on interactions between vegetation dynamics, fire spread, fire effects, and spatial context (Hann and others 2004). Fire regime group definitions have been altered from previous applications (Hann & Bunnell 2001; Schmidt and others 2002; Wildland Fire Communicator's Guide) to best approximate the definitions outlined in the Interagency FRCC Guidebook. These definitions were refined to create discrete, mutually exclusive criteria. This layer was created by linking the LANDFIRE Biophysical Settings (BpS) layer to the Fire Regime Group rulesets. This geospatial product should display a reasonable approximation of Fire Regime Group, as documented in the Refresh Model Tracker. The Historical Fire Regime Groups data layer categorizes simulated mean fire return intervals and fire severities into five fire regimes defined in the Interagency Fire Regime Condition Class Guidebook. The classes are defined as follows: Fire Regime I: 0 to 35 year frequency, low to mixed severity Fire Regime II: 0 to 35 year frequency, replacement severity Fire Regime III: 35 to 200 year frequency, low to mixed severity Fire Regime IV: 35 to 200 year frequency, replacement severity Fire Regime V: 200+ year frequency, any severity Additional data layer values were included to represent Water (111), Snow / Ice (112), Barren (131), and Sparsely Vegetated (132). Vegetated areas that never burned during the simulations were included in the category "Indeterminate Fire Regime Characteristics" (133); these vegetation types either had no defined fire behavior or had extremely low probabilities of fire ignition.

The Fire Regime Groups layer characterizes the presumed historical fire regimes within landscapes based on interactions between vegetation dynamics, fire spread, fire effects, and spatial context (Hann and others 2004). Fire regime group definitions have been altered from previous applications (Hann & Bunnell 2001; Schmidt and others 2002; Wildland Fire Communicator's Guide) to best approximate the definitions outlined in the Interagency FRCC Guidebook. These definitions were refined to create discrete, mutually exclusive criteria. This layer was created by linking the LANDFIRE Biophysical Settings (BpS) layer to the Fire Regime Group rulesets. This geospatial product should display a reasonable approximation of Fire Regime Group, as documented in the Refresh Model Tracker. The Historical Fire Regime Groups data layer categorizes simulated mean fire return intervals and fire severities into five fire regimes defined in the Interagency Fire Regime Condition Class Guidebook. The classes are defined as follows: Fire Regime I: 0 to 35 year frequency, low to mixed severity Fire Regime II: 0 to 35 year frequency, replacement severity Fire Regime III: 35 to 200 year frequency, low to mixed severity Fire Regime IV: 35 to 200 year frequency, replacement severity Fire Regime V: 200+ year frequency, any severity Additional data layer values were included to represent Water (111), Snow / Ice (112), Barren (131), and Sparsely Vegetated (132). Vegetated areas that never burned during the simulations were included in the category "Indeterminate Fire Regime Characteristics" (133); these vegetation types either had no defined fire behavior or had extremely low probabilities of fire ignition.