Fig 1.
A schematic illustration of how to derive the set of fuel breaks that constitutes a fire’s ignition polygon.
Fig 2.
Southern California landscape.
World Hillshade is used in the figure’s background (Sources: Esri, Airbus DS, USGS, NGA, NASA, CGIAR, N Robinson, NCEAS, NLS, OS, NMA, Geodatastyrelsen, Rijkswaterstaat, GSA, Geoland, FEMA, Intermap, and the GIS User Community).
Fig 3.
Illustration of data processing for 1 of 53,906 FSIM fires.
A: Intersecting fuel breaks with the fire footprint to identify the ignition polygon and its associated fuel breaks. B: Intersecting the ignition polygon with the fire flame length raster to identify the highest flame length along the fuel break segments enclosing the ignition polygon.
Fig 4.
Objective function values of the optimal solutions.
A: Maximizing AFB, all fires. B: Maximizing AFB, no large fires. C: Maximizing AWB, all fires. D: Maximizing AWB, no large fires. Note that the unit is “million fire acres” in A and C, while it is “thousand WUI acres” in B and D. Numbers are shown for the green lines only.
Fig 5.
Proportion (percentage) of number of fires being contained in the optimal solutions.
A: Maximizing AFB, all fires. B: Maximizing AFB, no large fires. C: Maximizing AWB, all fires. D: Maximizing AWB, no large fires. Note that in A and C, the percentage is calculated by the number of contained fires divided by 53,906; while in B and D, the percentage is calculated by the number of contained fires divided by 43,124. Percentages are shown for the green lines only.
Fig 6.
Some optimization treatment layouts considering the objective function of maximizing AWB and 20% largest fires are excluded.
A: Treating 10% FBN length. B: Treating 30% FBN length. C: Treating 50% FBN length. This figure only shows a portion of the Southern California landscape. More detailed solutions are presented in S3.4, S3.5 Figs in S3 Appendix. World Hillshade is used in the figure’s background (Sources: Esri, Airbus DS, USGS, NGA, NASA, CGIAR, N Robinson, NCEAS, NLS, OS, NMA, Geodatastyrelsen, Rijkswaterstaat, GSA, Geoland, FEMA, Intermap, and the GIS User Community).
Fig 7.
Comparing solutions from the optimization (OPT) models and the rule-based selection (RBS) models.
A: Maximizing AFB, all fires. B: Maximizing AFB, no large fires. C: Maximizing AWB, all fires. D: Maximizing AWB, no large fires. Note that solutions presented here are rescaled (divided by the objective function values from the RBS models). The original solutions can be found in Table S3.1 in S3 Appendix.