Data and code from: Wildfire exposure and hazard in the wildland-urban interface
Data files
Sep 25, 2026 version files 226.62 GB
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data.zip
226.59 GB
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README.md
9.41 KB
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results.zip
29.36 MB
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src.zip
16.68 KB
Abstract
In the decades since the wildland-urban interface (WUI) was first introduced as a priority area in wildfire management, a number of methods for mapping this zone have been developed that each rely on different approaches for identifying the spatial relationship between human habitation and wildland vegetation. Concurrently, simulation-based approaches to identifying values at risk have emerged to estimate wildfire hazard - that is, the likelihood and expected intensity of wildfire - based on fuels, topography, weather, and historical wildfire occurrence.
The aim of this study is to investigate differences between WUI mapping methods, including a novel approach based on historical property records. The WUI mapping method developed herein is based on structure densities from a dataset of historical settlement within the conterminous United States (HISDAC-US). This approach allows for the construction of a longitudinal set of WUI maps from 2000 through 2020 at five-year timesteps, enabling the assessment of regional growth patterns.
I tabulate the spatial extent, population, and number of structures identified as WUI by four different mapping methods within a range of simulated wildfire hazard levels, across a 10x10 km grid that spans the conterminous United States (CONUS). This allows for the comparison of not only values at risk within areas identified as WUI, but also the level of wildfire hazard faced by these values.
Project: Cadastral WUI Map
Author: Reed Humphrey
Source code
1. Dissolve GACC boundaries
src/dissolve_gacc_bounds.R
- Dissolves boundaries within GACCs.
- Input:
data/raw/NIFC_Bounds/National_PSA_Final_dissolved_20250113.gpkg
- Output:
data/raw/NIFC_Bounds/gacc_bounds.gpkg
2. Spatially index the Radeloff WUI map
src/index_radeloff.R
- Converts the Radeloff WUI map to a spatially-indexed GeoPackage to optimize subsequent queries.
- Input:
data/raw/Radeloff_WUI/RDS-2015-0012-4.zip
- Output:
data/raw/Radeloff_WUI/CONUS_WUI_block_1990_2020_change_v4.gpkg
3. Create the CONUS grid
src/create_conus_grid.R
- Creates a 10-kilometer grid across CONUS to be used for tabulations of values at risk.
- Input:
- TIGER/Line state boundaries (
data/raw/TIGER_Line/tl_2025_us_state)
- TIGER/Line state boundaries (
- Output:
- Multiple written to
data/processed/conus_grid
- Multiple written to
4. Construct the cadastral WUI map
src/classify_cadastral_wui.R
- Classifies WUI across CONUS using cadastral method.
- Input:
- HISDAC-US Built-up Property Locations (
data/raw/HISDAC-US/BUPL) - NLCD Annual datasets (
data/raw/NLCD)
- HISDAC-US Built-up Property Locations (
- Output:
- Multiple written to
data/processed/cadastral_wui
- Multiple written to
5. Tabulate values at risk
src/tab_values_by_wui_hazard.R
- Tabulates values at risk by WUI class and hazard level within the CONUS grid
- Input:
- WUI maps:
- Cadastral WUI map (
data/processed/cadastral_wui) - Radeloff WUI map (
data/raw/Radeloff_WUI) - Carlson WUI map (
data/raw/Carlson_WUI) - Chen WUI map (
data/raw/Chen_WUI)
- Cadastral WUI map (
- Hazard maps:
- Wildfire Risk to Communities (
data/raw/WRC_v2)
- Wildfire Risk to Communities (
- Values at risk:
- HISDAC-US Built-up Property Locations (
data/raw/HISDAC-US/BUPL) - HISDAC-US Built-up Property Records (
data/raw/HISDAC-US/BUPR) - HISDAC-US Land Use Counts (
data/raw/HISDAC-US/LU_Count) - WorldPop (
data/raw/WorldPop)
- HISDAC-US Built-up Property Locations (
- WUI maps:
- Output:
- Multiple written to
data/processed/values_by_wui_hazard
- Multiple written to
6. Summarize values at risk
src/sum_values_at_risk.R
- Summarizes the tabulations of values at risk into three statistics per WUI class and value at risk: total, expected annual exposed, and 90th percentile RPS.
- Input:
- Tabulations in
data/processed/values_by_wui_hazard
- Tabulations in
- Output:
- Multiple written to
data/processed/values_at_risk
- Multiple written to
7. Describe values at risk
src/describe_values_at_risk.R
src/describe_values_at_risk.Rmd
- Conducts descriptive analyses of values at risk
- Input:
- Multiple
- Output:
- Knitted PDF and PNGs written to
results/values_at_risk
- Knitted PDF and PNGs written to
8. Compare structure counts
src/compare_structure_counts.R
src/compare_structure_counts.Rmd
- Compares structure counts across source datasets
- Input:
- Multiple
- Output:
- Knitted PDF written to
results/structure_count_comparisons
- Knitted PDF written to
Data
Raw
Landcover
data/raw/NLCD/Annual_NLCD_LndCov_YYYY_CU_C1V0.tif
- NLCD Landcover classes for 2000, 2005, 2010, 2015, and 2020 (U.S. Geological Survey 2025)
- Downloaded from https://www.mrlc.gov/data
Values at risk
data/raw/HISDAC-US/BUPL/YYYY_BUPL.tif
- Built-up Property Locations for 2000, 2005, 2010, 2015, and 2020 (Ahn et al. 2024)
- Downloaded from https://dataverse.harvard.edu/dataset.xhtml?persistentId=doi:10.7910/DVN/U2P66Z
data/raw/HISDAC-US/BUPR/YYYY_BUPR.tif
- Built-up Property Records for 2000, 2005, 2010, 2015, and 2020 (Ahn et al. 2024)
- Downloaded from https://dataverse.harvard.edu/dataset.xhtml?persistentId=doi:10.7910/DVN/45B8IU
data/raw/HISDAC-US/NobuiltYear.tif
- Property records with unknown year built (Ahn et al. 2024)
- Downloaded from https://dataverse.harvard.edu/dataset.xhtml?persistentId=doi:10.7910/DVN/HHFM5E
data/raw/HISDAC-US/LU_Count/RO/Count_YYYY_RO.tif
data/raw/HISDAC-US/LU_Count/RI/Count_YYYY_RI.tif
- Residential owned (RO) and residential income (RI) property records for 2000, 2005, 2010, 2015, and 2020 (Ahn et al. 2024)
- Downloaded from https://dataverse.harvard.edu/dataset.xhtml?persistentId=doi:10.7910/DVN/PRJBUF
data/raw/WorldPop/usa_ppp_YYYY_UNadj.tif
- Population rasters for the United States for 2000, 2005, 2010, 2015, and 2020 (WorldPop and Bondarenko 2020)
- Downloaded from:
Comparison WUI maps
data/raw/Radeloff_WUI
- Zonal WUI maps for 1990, 2000, 2010, 2020 (Radeloff et al. 2023)
RDS-2015-0012-4.zipdownloaded from https://www.fs.usda.gov/rds/archive/catalog/RDS-2015-0012-4CONUS_WUI_block_1990_2020_change_v4.gpkgconverted from the zipped GDB by the scriptsrc/index_radeloff.R
data/raw/Carlson_WUI
- Point-based WUI map for ~2015 (Carlson et al. 2022)
- Downloaded from https://www.sciencebase.gov/catalog/item/617bfb43d34ea58c3c70038f
data/raw/Chen_WUI
- Raster WUI maps for 2000, 2005, 2010, 2015, and 2020 (Chen et al. 2024)
- Downloaded from https://datahub.hku.hk/projects/GlobalWUI/191163
Wildfire hazard
data/raw/WRC_v2
- Burn probability (BP) and risk to potential structures (RPS) layers from the WRC dataset, second edition (Scott et al. 2024)
- Downloaded from https://www.fs.usda.gov/rds/archive/catalog/RDS-2020-0016-2
Boundaries
data/raw/NIFC_Bounds
- Boundaries for Geographic Area Coordination Centers (GACCs)
National_PSA_Final_dissolved_20250113.gpkgdownloaded from https://data-nifc.opendata.arcgis.com/datasets/nifc::predictive-service-area-psa-boundaries-public/aboutgacc_bounds.gpkgdissolved by the scriptsrc/dissolve_gacc_bounds.R
data/raw/TIGER_Line/tl_2025_us_state
- TIGER/Line state boundaries (U.S. Census Bureau 2025)
- Downloaded from https://www.census.gov/geographies/mapping-files/time-series/geo/tiger-line-file.2025.html
Processed
CONUS grid
data/processed/conus_grid
- Raster and GeoPackage with CONUS grid cell numbers & boundaries.
- Produced by
src/create_conus_grid.R
Cadastral WUI map
data/processed/cadastral_wui
- Five rasters per timestep:
- Percentage of wildland vegetation (
wildpct_YYYY.tif) - Indicator layer for contiguous patches of wildland vegetation above the size & vegetation cover thresholds (
wildpatch_YYYY.tif) - Buffered patches of wildland vegetation (
wildbuffer_YYYY.tif) - Structure density (
strdens_YYYY.tif) - Final cadastral WUI classifications (
cadastral_wui_YYYY.tif)
- Percentage of wildland vegetation (
- Produced by
src/classify_cadastral_wui.R
Tabulations of values at risk
data/processed/values_by_wui_hazard
- One raster per WUI map & timestep with layers for each value at risk, stratified by WUI and hazard class
- Produced by
src/tab_values_by_wui_hazard.R
Summarized values at risk
data/processed/values_at_risk
- One raster per WUI map & timestep, with summary statistics for each value at risk: total and 90th percentile RPS.
- Produced by
src/sum_values_at_risk.R
Structure count comparisons
data/processed/structure_count_comparisons
- Rasters with BUPL/BUPR/HU counts aggregated across 10-km grid
- Rasters with BUPR built year missingness and data quality
- Produced by
src/compare_structure_counts.R
Results
Cadastral WUI maps
results/cadastral_wui_maps
- Maps that show/compare the cadastral WUI classifications for different years
Input data maps
results/input_data_maps
- Maps that illustrate the various input data sources for the example location of Bend, OR
Structure count comparisons
results/structure_count_comparisons
- Comparisons of the number of structures in source datasets (BUPL/BUPR/NBY/HU) & year-built missingness
- Data quality map for the BUPR data
Values at risk
results/values_at_risk
- Tables and figures used in the manuscript to compare values at risk under different mapping methods
WUI comparison maps
results/wui_comp_maps
- Maps that compare WUI classifications between different methods