Fig. 5
From: Wildfire probability estimated from recent climate and fine fuels across the big sagebrush region
Assessment of model performance at extreme climate conditions, showing low (blue) and high (red) values of the three climate predictors. Main panels show observed (circles) and predicted (triangles) mean annual wildfire probability across a range of aboveground biomass of (a, c, e) annual grasses and forbs and (b, d, f) perennial grasses and forbs. Corresponding fire return intervals (FRI) are shown on the secondary (right) y-axis. Data are shown separately for pixels having low (< 20th percentile; reds) or high (> 80th percentile; blues) levels of a, b mean temperature; c, d annual precipitation; and e, f proportion summer precipitation (PSP). Biomass values were binned by percentile, and the mean observed and predicted annual wildfire probability is shown for each percentile of biomass. To illustrate, the right-most red circle in panel a shows the mean observed wildfire probability across pixels with low precipitation (< 20th percentile) where biomass of annuals is between the 99th and 100th percentile, and the right-most yellow triangle in that panel shows the mean predicted wildfire probability for those same pixels. Each point on the figure represents the mean of ~ 50,000 observations. Best fit lines in the main panels were generated using locally estimated scatterplot smoothing and are included to help visualize the trends in the data. In the insets, the mean observed and predicted annual wildfire probability (%) values shown in the main panels are plotted against each other (1:1 line shown for reference), with colors representing data from areas with low (red) and high (blue) levels of the respective climate variable. The 20th (low) and 80th (high) percentiles of the climate variables were 6.7 °C and 10.9 °C temperature, 226 mm and 420 mm precipitation, and 0.104 and 0.321 PSP, respectively