Fig. 3
From: Estimating WUI exposure probability to a nearby wildfire
Illustration of four potential focal area selections: a creating straight lines to connect a WUI block and corresponding fire perimeters; b forming rectangular focal areas; c connecting boundaries between fire perimeters and WUI as focal zones; d creating funnel-shaped focal analysis areas (used in this study). In d, the three funnels form a “cluster.” Because the main axis of each funnel matches the unique shortest-distance-line between a WUI and a specific fire perimeter, the three funnels may overlap partially. The smallest funnel (delineated by dashed blue lines) in d is formed by the “closest” fire perimeter in the cluster