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1. Introduction Wildland fires often occur in forested environments. Fire spread and smoke dispersion through these environments are affected by ambient and fire-induced atmospheric circulations, which, in turn, are influenced by the presence of forest vegetation ( Albini and Baughman 1979 ; Ryan 2002 ; Taylor et al. 2004 ; Kiefer et al. 2014 ; Seto et al. 2014 ; Heilman et al. 2015 ). The properties of atmospheric mean and turbulent circulations inside forest vegetation layers in the
1. Introduction Wildland fires often occur in forested environments. Fire spread and smoke dispersion through these environments are affected by ambient and fire-induced atmospheric circulations, which, in turn, are influenced by the presence of forest vegetation ( Albini and Baughman 1979 ; Ryan 2002 ; Taylor et al. 2004 ; Kiefer et al. 2014 ; Seto et al. 2014 ; Heilman et al. 2015 ). The properties of atmospheric mean and turbulent circulations inside forest vegetation layers in the
, to inform land-planning and life-safety management policies, and to issue warnings to the general public. In Australia, where wildfires are more commonly called bushfires, the fire danger rating systems of McArthur (1966 , 1967) are used. These systems combine weather and fuel information to calculate an index of fire danger that is used to define the fire danger rating. Of the two fire danger rating systems in use in Australia, we constrain our focus to the forest fire danger index (FFDI
, to inform land-planning and life-safety management policies, and to issue warnings to the general public. In Australia, where wildfires are more commonly called bushfires, the fire danger rating systems of McArthur (1966 , 1967) are used. These systems combine weather and fuel information to calculate an index of fire danger that is used to define the fire danger rating. Of the two fire danger rating systems in use in Australia, we constrain our focus to the forest fire danger index (FFDI
1. Introduction Atmospheric turbulence regimes in the vicinity of wildland fires, which often occur in forested environments, can affect fire behavior and the dispersion of smoke ( Clements et al. 2008 ; Mandel et al. 2009 ; Sun et al. 2009 ; Goodrick et al. 2013 ; Simpson et al. 2016 ). Fortunately, recent observational studies during wildland fire events have made great strides in improving our understanding of the evolution and properties of fire-induced atmospheric turbulence regimes
1. Introduction Atmospheric turbulence regimes in the vicinity of wildland fires, which often occur in forested environments, can affect fire behavior and the dispersion of smoke ( Clements et al. 2008 ; Mandel et al. 2009 ; Sun et al. 2009 ; Goodrick et al. 2013 ; Simpson et al. 2016 ). Fortunately, recent observational studies during wildland fire events have made great strides in improving our understanding of the evolution and properties of fire-induced atmospheric turbulence regimes
disproportionate amount to the total vertical turbulent heat-flux fields within forest vegetation layers. Although studies of sweep–ejection dynamics in the lower ABL have been numerous over the last four decades, little is known about the sweep–ejection dynamics that occur in the highly perturbed environment surrounding wildland fires. Beer (1991) and Pimont et al. (2009) noted that coherent turbulent structures leading to turbulent heat- and momentum-flux sweep and ejection events within forest
disproportionate amount to the total vertical turbulent heat-flux fields within forest vegetation layers. Although studies of sweep–ejection dynamics in the lower ABL have been numerous over the last four decades, little is known about the sweep–ejection dynamics that occur in the highly perturbed environment surrounding wildland fires. Beer (1991) and Pimont et al. (2009) noted that coherent turbulent structures leading to turbulent heat- and momentum-flux sweep and ejection events within forest
1. Introduction Wildland fire is a dominant disturbance regime in Canadian forests, particularly in the boreal forest region where fire is a process critical to the very existence of primary boreal species such as pine, spruce, and aspen and is responsible for shaping landscape diversity and influencing energy flows and biogeochemical cycling ( Stocks et al. 2002 ). Stocks et al. (1996) examined the spatial distribution of large fires in Canada during the 1980s when an average of almost 10
1. Introduction Wildland fire is a dominant disturbance regime in Canadian forests, particularly in the boreal forest region where fire is a process critical to the very existence of primary boreal species such as pine, spruce, and aspen and is responsible for shaping landscape diversity and influencing energy flows and biogeochemical cycling ( Stocks et al. 2002 ). Stocks et al. (1996) examined the spatial distribution of large fires in Canada during the 1980s when an average of almost 10
indigenous people controlling fires locally and igniting fires for management of the land ( Anderson 2006 ; van Wagtendonk 2007 ). When European colonizers decimated the Native population, began logging forests and tilling grasslands, and brought livestock to graze, the vegetation and fire regime in the west were altered significantly. In the early twentieth century, the U.S. Forest Service (USFS) set out to completely suppress all fires on USFS land ( Marlon et al. 2012 ; van Wagtendonk 2007 ). This
indigenous people controlling fires locally and igniting fires for management of the land ( Anderson 2006 ; van Wagtendonk 2007 ). When European colonizers decimated the Native population, began logging forests and tilling grasslands, and brought livestock to graze, the vegetation and fire regime in the west were altered significantly. In the early twentieth century, the U.S. Forest Service (USFS) set out to completely suppress all fires on USFS land ( Marlon et al. 2012 ; van Wagtendonk 2007 ). This
MARCH, 1921. MONTHLY WEATHER REVIEW.EVAPORATION AND FOREST FIRES.By E. N. MUNNS, Forest Examiner. 5s/. 5'73 : 6 34.7. %3'149(California District U. 8. Forest Service, Feb. 17,1021.)EYNOp8IB.Hitherto a arently, little attempt has been made by foresters and t% correlate the factors of climate and forest fires. The m:&z%%is paper ia to show that the occurrence and spread of large fmt fires are coincident with a greatly increased rate of evapora.tion or a decrease in vapor preesure
MARCH, 1921. MONTHLY WEATHER REVIEW.EVAPORATION AND FOREST FIRES.By E. N. MUNNS, Forest Examiner. 5s/. 5'73 : 6 34.7. %3'149(California District U. 8. Forest Service, Feb. 17,1021.)EYNOp8IB.Hitherto a arently, little attempt has been made by foresters and t% correlate the factors of climate and forest fires. The m:&z%%is paper ia to show that the occurrence and spread of large fmt fires are coincident with a greatly increased rate of evapora.tion or a decrease in vapor preesure
1. Introduction Wildfire activity is strongly affected by four factors: fuels, climate/weather, ignition agents, and people ( Flannigan et al. 2005 ). Where fuel is available, weather is the most important factor in shaping fire regimes in many areas of the world ( Flannigan et al. 2009 ). Fires are a global phenomenon extending from the boreal forests of Canada and Siberia down to Amazonia and the central African rain forests. Especially in a savanna ecoclimate, such as the Sahel and west
1. Introduction Wildfire activity is strongly affected by four factors: fuels, climate/weather, ignition agents, and people ( Flannigan et al. 2005 ). Where fuel is available, weather is the most important factor in shaping fire regimes in many areas of the world ( Flannigan et al. 2009 ). Fires are a global phenomenon extending from the boreal forests of Canada and Siberia down to Amazonia and the central African rain forests. Especially in a savanna ecoclimate, such as the Sahel and west
reliability of its quantities varies substantially. Air temperature estimated from the reanalysis showed the lowest biases and standard deviation of errors; in the meantime, the accuracy of the precipitation and wind required for FWI calculation is substantially lower because of their high variability at a small spatial scale ( Decker et al. 2012 ; Akinsanola et al. 2017 , Beck et al. 2017 ). In addition, FWI was developed in Canada to reflect the behavior of forest fires and was calibrated for 16 major
reliability of its quantities varies substantially. Air temperature estimated from the reanalysis showed the lowest biases and standard deviation of errors; in the meantime, the accuracy of the precipitation and wind required for FWI calculation is substantially lower because of their high variability at a small spatial scale ( Decker et al. 2012 ; Akinsanola et al. 2017 , Beck et al. 2017 ). In addition, FWI was developed in Canada to reflect the behavior of forest fires and was calibrated for 16 major
1. Introduction The Canadian Forest Fire Weather Index (FWI) System ( Van Wagner 1987 ) has been in use across Canada for the past 30 years in the daily operations of fire management agencies ( http://cwfis.cfs.nrcan.gc.ca/ ). The FWI System uses daily weather observations (temperature, rainfall, relative humidity, and wind velocity) to estimate the moisture content of three different fuel classes and uses these to generate a set of relative indicators of potential rate of fire spread, fire
1. Introduction The Canadian Forest Fire Weather Index (FWI) System ( Van Wagner 1987 ) has been in use across Canada for the past 30 years in the daily operations of fire management agencies ( http://cwfis.cfs.nrcan.gc.ca/ ). The FWI System uses daily weather observations (temperature, rainfall, relative humidity, and wind velocity) to estimate the moisture content of three different fuel classes and uses these to generate a set of relative indicators of potential rate of fire spread, fire
