Change in simultaneous occurrence of 1000+ Acre and 75th Percentile fires, comparing 1984-2001 to 2002-2019. Both maps are divided into regions, with each region representing one GACC. The left panel corresponds to all large fires (ALF, 1000+ acres) while the right panel corresponds to 75th percentile fires (VLF), as determined for each GACC. The shading of each region indicates the change in number of ALF or VLF, respectively, between the two time periods. Red represents an increased number of fires, while blue represents a decreased number of fires. More large fires (1000 acres or greater) occurred during the peak month of simultaneity in the more recent time period, i.e., in 2002-2019 relative to 1984-2001. Statistical significance of the change in number of fires is denoted with asterisks, (*) corresponds to p < 0.05, (**) corresponds to p < 0.01 and (***) correspond to p < 0.001. Data on simultaneous wildfire occurrence come from the Monitoring Trends and Burn Severity (MTBS) project. Approach is based on Podschwit & Cullen (2020) https://doi.org/10.1071/WF19150. This visualization was made as part of NSF Growing Convergence Project 2019762.
Simultaneous Occurrence of 1000+ Acre Fires in US Regions comparing 1984-2001 and 2002-2019
