Enhanced prediction of extreme fire weather conditions in spring using the Hot-Dry-Windy Index in Alberta, Canada
Kyle G. Elliott A * , Mike D. Flannigan B and Cordy Tymstra AA
B
Abstract
Fire weather indices forecast fire behaviour and provide valuable information for wildland fire prevention, preparedness, and suppression. However, these indices do not directly account for atmospheric conditions aloft. The province of Alberta, Canada has experienced extreme fire weather conditions during spring for decades, leading to the continued occurrence of disastrous wildland fires.
We examined the Hot-Dry-Windy Index (HDWI) and spread days over the first 4 days of 80 large wildland fires that started in May 1990–2019 in Alberta.
HDWI values were calculated using ERA5 reanalysis data from the 1000, 975 and 950 hPa levels. Differences between HDWI distributions on spread days and non-spread days were examined using permutation tests. Initial Spread Index was also examined as it is considered an important Fire Weather Index System value for wildland fire spread during spring in Alberta.
Higher median HDWI values were observed on spread days than non-spread days, where median Initial Spread Index values showed little to no difference.
This analysis suggests that HDWI can contribute to the prediction of significant spring wildland fire spread in Alberta.
Forecasted HDWI and HDWI climatologies may provide additional decision support for wildland fire management agencies.
Keywords: Alberta, Canada, fire weather, HDWI, Hot-Dry-Windy Index, prediction, spring wildfires, wildfire spread, wildland fire.
References
Alexander ME (2010) Surface fire spread potential in trembling aspen during summer in the Boreal Forest Region of Canada. The Forestry Chronicle 86(2), 200-212.
| Crossref | Google Scholar |
Beverly JL, Flannigan MD, Stocks BJ, Bothwell P (2011) The association between Northern Hemisphere climate patterns and interannual variability in Canadian wildfire activity. Canadian Journal of Forest Research 41, 2193-2201.
| Crossref | Google Scholar |
Bolton D (1980) The computation of equivalent potential temperature. Monthly Weather Review 108, 1046-1053.
| Crossref | Google Scholar |
Chrosciewicz Z (1986) Foliar moisture content variations in four coniferous tree species of central Alberta. Canadian Journal of Forest Research 16, 157-162.
| Crossref | Google Scholar |
CDS (Copernicus Climate Data Store) (2021) ERA5 hourly data on pressure levels from 1959 to present. Available at https://cds.climate.copernicus.eu/datasets/reanalysis-era5-pressure-levels?tab=overview
Flannigan MD, Logan KA, Amiro BD, Skinner WR, Stocks BJ (2005) Future area burned in Canada. Climatic Change 72, 1-16.
| Crossref | Google Scholar |
Flannigan MD, Stocks B, Turetsky M, Wotton M (2009) Impacts of climate change on fire activity and fire management in the circumboreal forest. Global Change Biology 15, 549-560.
| Crossref | Google Scholar |
Flat Top Complex Wildfire Review Committee (2012) Flat Top Complex Review. Environment and Sustainable Resource Development, May 2012. Available at https://open.alberta.ca/publications/9781460102732
Government of Alberta (2019) ‘Historical data.’ (Alberta Forestry, Parks and Tourism, Wildfire: Edmonton, AB, Canada) Available at https://www.alberta.ca/wildfire-maps-and-data.aspx#jumplinks-2
Government of Alberta (2023) ‘Fire Weather Index Legend.’ (Alberta Forestry and Parks, Alberta Wildfire: Edmonton, AB, Canada) Available at https://www.alberta.ca/fire-danger
Hanes CC, Wang X, Jain P, Parisien M-A, Little JM, Flannigan MD (2018) Fire-regime changes in Canada over the last half century. Canadian Journal of Forest Research 49, 256-269.
| Crossref | Google Scholar |
Hanes CC, Wotton BM, Woolford DG, Martell DL (2020) Preceding fall drought conditions and overwinter precipitation effects on spring wildland fire activity in Canada. Fire 3, 24.
| Crossref | Google Scholar |
Killough D (2021) Hot-Dry-Windy Index offers improvement for fire prediction. Forestnet.com, TimberWest Magazine, January/February Issue: 34–36. Available at https://issuu.com/forestnet2/docs/01-02.21_tw_issueweb
McDonald JM, Srock AF, Charney JJ (2018) Development and application of a Hot-Dry-Windy Index (HDW) climatology. Atmosphere 9, 285.
| Crossref | Google Scholar |
McElhinny M, Beckers JF, Hanes C, Flannigan MD, Jain P (2020) A high-resolution reanalysis of global fire weather from 1979 to 2018 – overwintering the Drought Code. Earth System Science Data 12, 1823-1833.
| Crossref | Google Scholar |
Parisien M-A, Barber QE, Flannigan MD, Jain P (2023) Broadleaf tree phenology and springtime wildfire occurrence in boreal Canada. Global Change Biology 29, 6106-6119.
| Crossref | Google Scholar | PubMed |
Podur J, Wotton BM (2011) Defining fire spread event days for fire-growth modelling. International Journal of Wildland Fire 20, 497-507.
| Crossref | Google Scholar |
R Core Team (2020) ‘R: A language and environment for statistical computing.’ (R Foundation for Statistical Computing: Vienna, Austria) Available at https://www.R-project.org/
Srock AF, Charney JJ, Potter BE, Goodrick SL (2018) The Hot-Dry-Windy Index: a new fire weather index. Atmosphere 9, 279.
| Crossref | Google Scholar |
Stocks BJ, Mason JA, Todd JB, Bosch EM, Wotton BM, Amiro BD, Flannigan MD, Hirsch KG, Logan KA, Martell DL, Skinner WR (2002) Large forest fires in Canada, 1959-1997. Journal of Geophysical Research 108, 8149 2002.
| Crossref | Google Scholar |
Tymstra C, Woolford DG, Flannigan MD (2019) Statistical surveillance thresholds for enhanced situational awareness of spring wildland fire activity in Alberta, Canada. Journal of Environmental Statistics 9(4), 1-26.
| Google Scholar |
Tymstra C, Jain P, Flannigan MD (2021) Characterisation of initial fire weather conditions for large spring wildfires in Alberta, Canada. International Journal of Wildland Fire 30, 823-835.
| Crossref | Google Scholar |
United States Department of Agriculture (2022) Hot-Dry-Windy Index. Real-Time Product Suite website. Available at https://hdwindex.fs2c.usda.gov/abouthdw.html
Wang X, Thompson DK, Marshall GA, Tymstra C, Carr R, Flannigan MD (2015) Increasing frequency of extreme fire weather in Canada with climate change. Climatic Change 130, 573-586.
| Crossref | Google Scholar |
Wexler A (1976) Vapor pressure formulation for water in range 0 to 100°C. A revision. Journal of Research of the National Bureau of Standards—A. Physics and Chemistry 80A, 775-785.
| Crossref | Google Scholar | PubMed |
Wotton BM (2009) Interpreting and using outputs from the Canadian Forest Fire Danger Rating System in research applications. Environmental Ecology Statistics 16, 107-131.
| Crossref | Google Scholar |