NBIC-ACS Stage 2 Canadian Forest Fire Weather Index - projected scenarios, 20% and 10% annual exceedance probabilities

Canadian Forest Fire Weather Index (FWI) is a fire weather potential index that describes how current weather conditions and recent precipitation patterns could support a landscape fire. While originally was developed for boreal forests, it is now adapted for use in various regions and climates and include other vegetations like grasslands, broadleaf forest and shrublands. FWI calculations are based on Van Wagner & Pickett (1985) and dependent on air temperature, relative humidity, precipitation and wind speed. Returned values start from 0 but don’t have an upper bound constraint. Values above 200 were not anticipated to occur in Canada (Van Wagner (1987) but are regularly reported in Australia. The data provided here is unbounded.
Here we provide predicted upper-bound FWI values across the Australian landscape, defined for a set of annual exceedance probabilities (AEP) modelled using extreme values analysis on more than 43 years of daily data.
The FWI potential rasters represent reasonable worst case extreme conditions. Specifically, the rasters represent the FWI potential for given AEPs of 20%, 10%, 5%, 2% and 1%. These FWI AEPs are based on the projected weather timeseries developed by NBIC using the historical regional weather reanalysis dataset BARRA-R2 [1], and CMIP6-CCAM Regional Climate Models (RCM) [2].
The Regional Climate Models (RCM) considered are:
• ACCESS ESM 1.5
• EC-Earth 3
• CMCC ESM2
• CNRM ESM 2.1
• NCAR CESM2
• NorESM2 MM
The future climate change scenarios considered are:
• Shared Socioeconomic Pathway (SSP) SSP 1-26: Sustainability
• SSP 3-70: Regional Rivalry
• SSP 3-70: Regional Rivalry, using wind speed from the baseline scenario
The combination of RCMs and future climate change scenarios results in a suite of 18 projected FWI potential datasets.
Here we provide predicted upper-bound FWI values across the Australian landscape, defined for a set of annual exceedance probabilities (AEP) modelled using extreme values analysis on more than 43 years of daily data.
The FWI potential rasters represent reasonable worst case extreme conditions. Specifically, the rasters represent the FWI potential for given AEPs of 20%, 10%, 5%, 2% and 1%. These FWI AEPs are based on the projected weather timeseries developed by NBIC using the historical regional weather reanalysis dataset BARRA-R2 [1], and CMIP6-CCAM Regional Climate Models (RCM) [2].
The Regional Climate Models (RCM) considered are:
• ACCESS ESM 1.5
• EC-Earth 3
• CMCC ESM2
• CNRM ESM 2.1
• NCAR CESM2
• NorESM2 MM
The future climate change scenarios considered are:
• Shared Socioeconomic Pathway (SSP) SSP 1-26: Sustainability
• SSP 3-70: Regional Rivalry
• SSP 3-70: Regional Rivalry, using wind speed from the baseline scenario
The combination of RCMs and future climate change scenarios results in a suite of 18 projected FWI potential datasets.