scholarly journals Observed versus predicted fire behavior in an Alaskan black spruce forest ecosystem: an experimental fire case study

Fire Ecology ◽  
2019 ◽  
Vol 15 (1) ◽  
Author(s):  
Stacy A. Drury
Keyword(s):  
Black Spruce ◽  
Fire Behavior ◽  
Flame Length ◽  
Behavior Modeling ◽  
Fire Intensity ◽  
Modeling Tools ◽  
Rate Of Spread ◽  
Fire Behavior Modeling ◽  
Modeling Systems ◽  
Hazard And Risk

Abstract Background Fire managers tasked with assessing the hazard and risk of wildfire in Alaska, USA, tend to have more confidence in fire behavior prediction modeling systems developed in Canada than similar systems developed in the US. In 1992, Canadian fire behavior systems were adopted for modeling fire hazard and risk in Alaska and are used by fire suppression specialists and fire planners working within the state. However, as new US-based fire behavior modeling tools are developed, Alaskan fire managers are encouraged to adopt the use of US-based systems. Few studies exist in the scientific literature that inform fire managers as to the efficacy of fire behavior modeling tools in Alaska. In this study, I provide information to aid fire managers when tasked with deciding which system for modeling fire behavior is most appropriate for their use. On the Magitchlie Creek Fire in Alaska, I systematically collected fire behavior characteristics within a black spruce (Picea mariana [Mill.] Britton, Sterns & Poggenb.) ecosystem under head fire conditions. I compared my fire behavior observations including flame length, rate of spread, and head fire intensity with fire behavior predictions from the US fire modeling system BehavePlus, and three Canadian systems: RedAPP, CanFIRE, and the Crown Fire Initiation and Spread system (CFIS). Results All four modeling systems produced reasonable rate of spread predictions although the Canadian systems provided predictions slightly closer to the observed fire behavior. The Canadian fire behavior prediction modeling systems RedAPP and CanFIRE provided more accurate predictions of head fire intensity and fire type than BehavePlus or CFIS. Conclusions The most appropriate fire behavior modeling system for use in Alaskan black spruce ecosystems depends on what type of questions are being asked. For determining the rate of fire movement across a landscape, REDapp, CanFIRE, CFIS, or BehavePlus can all be expected to provide reasonably accurate estimates of rate of spread. If fire managers are interested in using predicted flame length or energy produced for informing decisions such as which firefighting tactics will be successful, or for evaluating the ecological impacts due to burning, then the Canadian fire modeling systems outperformed BehavePlus in this case study.

Examining fire behavior in mesquite - acacia shrublands

2005 ◽  
Vol 14 (2) ◽  
pp. 131 ◽  
Author(s):  
Tamara J. Streeks ◽  
M. Keith Owens ◽  
Steve G. Whisenant
Keyword(s):  
Flame Temperature ◽  
Fire Behavior ◽  
Fire Spread ◽  
Flame Length ◽  
South Texas ◽  
Fire Intensity ◽  
Rate Of Spread ◽  
Vegetation Shift ◽  
Naturally Occurring ◽  
Behavior Systems

The vegetation of South Texas has changed from mesquite savanna to mixed mesquite–acacia (Prosopis–Acacia) shrubland over the last 150 years. Fire reduction, due to lack of fine fuel and suppression of naturally occurring fires, is cited as one of the primary causes for this vegetation shift. Fire behavior, primarily rate of spread and fire intensity, is poorly understood in these communities, so fire prescriptions have not been developed. We evaluated two current fire behavior systems (BEHAVE and the CSIRO fire spread and fire danger calculator) and three models developed for shrublands to determine how well they predicted rate of spread and flame length during three summer fires within mesquite–acacia shrublands. We also used geostatistical analyses to examine the spatial pattern of net heat, flame temperature and fuel characteristics. The CSIRO forest model under-predicted the rate of fire spread by an average of 5.43 m min−1 and over-predicted flame lengths by 0.2 m while the BEHAVE brush model under-predicted rate of spread by an average of 6.57 m min−1 and flame lengths by an average of 0.33 m. The three shrubland models did not consistently predict the rate of spread in these plant communities. Net heat and flame temperature were related to the amount of 10-h fuel on the site, but were not related to the cover of grasses, forbs, shrubs, or apparent continuity of fine fuel. Fuel loads were typical of South Texas shrublands, in that they were uneven and spatially inconsistent, which resulted in an unpredictable fire pattern.

Exploratory analysis of the variables affecting initial attack hot-spotting containment rate

1991 ◽  
Vol 21 (4) ◽  
pp. 540-544 ◽  
Author(s):  
Peter J. Murphy ◽  
Paul M. Woodard ◽  
Dennis Quintilio ◽  
Stephen J. Titus
Keyword(s):  
Forest Cover ◽  
Black Spruce ◽  
Fire Behavior ◽  
Correlation Coefficients ◽  
Flame Length ◽  
Weather Variables ◽  
Weather Index ◽  
Fire Weather Index ◽  
Rate Of Spread ◽  
Forest Cover Types

Hot-spotting containment rates were determined for 18 fires of various intensities in two common boreal forest cover types: 8 in jack pine (Pinusbanksiana Lamb.) and 10 in black spruce (Piceamariana (Mill.) B.S.P.). Hot-spotting containment rates did not differ significantly between the two cover types. Correlation coefficients showed that hot-spotting containment rates were more closely related to fire behavior than to weather variables measured as part of the Canadian Forest Fire Weather Index System. Hot-spotting containment rate (HCR; m/man-hour) may be predicted based on rate of spread (ROS; m/min) and flame length (FL; m) using the following model: HCR = exp(6.0140 – 0.1830ROS – 0.1201FL). This model was fitted using weighted nonlinear regression; the R2-value was 0.76.

scholarly journals COMPORTAMENTO DO FOGO, EM CONDIÇÕES DE LABORATÓRIO, EM COMBUSTÍVEIS PROVENIENTES DE UM POVOAMENTO DE Pinus elliottii L.

FLORESTA ◽  
2004 ◽  
Vol 34 (2) ◽  
Author(s):  
Luciana Valle De Loro ◽  
Nelson Akira Hiramatsu
Keyword(s):  
Laboratory Test ◽  
Fire Behavior ◽  
Pinus Elliottii ◽  
Fire Spread ◽  
Flame Length ◽  
Flame Height ◽  
Fire Intensity ◽  
Forest Fuels ◽  
Rate Of Spread ◽  
Fire Laboratory

De um povoamento de Pinus elliottii localizado na Fazenda Canguiri-UFPR, foram coletadas seis amostras de material combustível superficial. Este material foi separado em classes, pesado e levado para o laboratório. Efetuou-se a queima da classe acículas num leito de areia no laboratorio, em seis queimas, sendo cada queima com acículas proveniente de cada uma das amostras coletadas. Foram medidas a altura, o comprimento e a velocidade de propagação do fogo. Aplicou-se para cada queima cerca de 746 g de acículas, equivalente a 0,678 Kg/m2, com uma espessura média de 3 cm. Foram obtidos como dados médios: velocidade de propagação de 0,00423 m/s, comprimento da chama de 35,22 cm e altura de 38,79 cm, resultando numa intensidade do fogo igual a 57,07 kW/m. O resíduo médio ficou na ordem de 40,3 %. FIRE BEHAVIOR, IN LABORATORY CONDITIONS, OF FOREST FUELS FROM A Pinus elliottii L. STAND Abstract Pinus elliottii needles from a stand located at Fazenda Canguiri-UFPR were collected to run a laboratory test on fire behavior. The fuel from six samples was separated in classes, weight, and taken to the Federal University of Paraná Forest Fire Laboratory. The pine needles were burned in a sand bed. About 746.0g of each one of the six samples, equivalent to 0.678kg.m-2 and 3cm depth, were used in each fire run. Flame height and length, and rate of spread were measured. The average values obtained were: fire spread, 0,00423 m.s-1, flame length, 35,22cm, and flame height, 38,79cm. Fire intensity was of 57,07 kW.m-1 and residual fuel content about 40,3%.

Flame characteristics of wind-driven surface fires

1986 ◽  
Vol 16 (6) ◽  
pp. 1293-1300 ◽  
Author(s):  
Ralph M. Nelson Jr. ◽  
Carl W. Adkins
Keyword(s):  
Boundary Layer ◽  
Tilt Angle ◽  
Fire Behavior ◽  
Flame Length ◽  
Fire Intensity ◽  
Square Root ◽  
Pine Needle ◽  
Weather Variables ◽  
Practical Applications ◽  
Surface Fires

Twenty-two fires in a laboratory wind tunnel and 8 field fires were studied with video techniques to determine relationships between their flame characteristics and fire behavior. The laboratory fires were in pine needle fuel beds with and without an overlying stratum of live vegetation. These fuels simulated 2-year roughs in southeastern fuel types. The field bums were in 1- and 2-year roughs in similar fuels. Byram's fire intensity ranged from 98 to 590 kW/m in the laboratory, and from 355 to 2755 kW/m in the field. Flame lengths were proportional to the square root of fire intensity when fuel consumption exceeded 0.5 kg/m2, in agreement with predictions from buoyant flame theory. However, for burns in the needle layer (consumption approximately 0.5 kg/m2), flame lengths were constant at about 0.5 m, regardless of intensity. Similar values were observed on two of the field fires. It is speculated that flame length is limited by a boundary layer pattern for the overall flow, even though the flames themselves did not exhibit boundary layer characteristics. Also, laboratory correlations of flame tilt angle and fire intensity with other fire and weather variables depart from buoyant flame theory. Further study under field conditions is needed before relationships involving flame tilt angle, fire intensity, and wind speed should be used in practical applications.

Estimation of Byram’s Fire Intensity and Rate of Spread from Spaceborne Remote Sensing Data in a Savanna Landscape

Fire ◽  
2021 ◽  
Vol 4 (4) ◽  
pp. 65
Author(s):  
Gernot Ruecker ◽  
David Leimbach ◽  
Joachim Tiemann
Keyword(s):  
Remote Sensing ◽  
Fuel Consumption ◽  
Spatial Resolution ◽  
Fire Behavior ◽  
Remote Sensing Data ◽  
Fire Intensity ◽  
Rate Of Spread ◽  
Radiative Power ◽  
Sentinel 2 ◽  
Fire Radiative Power

Fire behavior is well described by a fire’s direction, rate of spread, and its energy release rate. Fire intensity as defined by Byram (1959) is the most commonly used term describing fire behavior in the wildfire community. It is, however, difficult to observe from space. Here, we assess fire spread and fire radiative power using infrared sensors with different spatial, spectral and temporal resolutions. The sensors used offer either high spatial resolution (Sentinel-2) for fire detection, but a low temporal resolution, moderate spatial resolution and daily observations (VIIRS), and high temporal resolution with low spatial resolution and fire radiative power retrievals (Meteosat SEVIRI). We extracted fire fronts from Sentinel-2 (using the shortwave infrared bands) and use the available fire products for S-NPP VIIRS and Meteosat SEVIRI. Rate of spread was analyzed by measuring the displacement of fire fronts between the mid-morning Sentinel-2 overpasses and the early afternoon VIIRS overpasses. We retrieved FRP from 15-min Meteosat SEVIRI observations and estimated total fire radiative energy release over the observed fire fronts. This was then converted to total fuel consumption, and, by making use of Sentinel-2-derived burned area, to fuel consumption per unit area. Using rate of spread and fuel consumption per unit area, Byram’s fire intensity could be derived. We tested this approach on a small number of fires in a frequently burning West African savanna landscape. Comparison to field experiments in the area showed similar numbers between field observations and remote-sensing-derived estimates. To the authors’ knowledge, this is the first direct estimate of Byram’s fire intensity from spaceborne remote sensing data. Shortcomings of the presented approach, foundations of an error budget, and potential further development, also considering upcoming sensor systems, are discussed.

scholarly journals Modeling sub-boreal forest canopy bulk density in Minnesota, USA, using synthetic aperture radar and optical satellite sensor data

Fire Ecology ◽  
2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Peter T. Wolter ◽  
Jacob J. Olbrich ◽  
Patricia J. Johnson
Keyword(s):  
Fire Behavior ◽  
Ground Level ◽  
Behavior Modeling ◽  
Remote Detection ◽  
Sensor Data ◽  
Fire Behavior Modeling ◽  
Fuel Density ◽  
National Estimates ◽  
Satellite Sensor Data ◽  
Satellite Sensor

Abstract Background National estimates of canopy bulk density (CBD; kg m−3) for fire behavior modeling are generated and supported by the LANDFIRE program. However, locally derived estimates of CBD at finer scales are preferred over national estimates if they exist, as the absolute accuracy of the LANDFIRE CBD product is low and varies regionally. Active sensors (e.g., lidar or radar) are better suited for this task, as passive sensors are ill equipped to detect differences among key vertical fuel structures, such as coniferous surface fuels (≤2 m high) and canopy fuels above this threshold—a key categorical fuel distinction in fire behavior modeling. However, previous efforts to map CBD using lidar sensor data in the Superior National Forest (SNF) of Minnesota, USA, yielded substandard results. Therefore, we use a combination of dormant-season synthetic aperture radar (SAR) and optical satellite sensor data to (1) expand detectability of coniferous fuels among mixed forest canopies to improve the accuracy of CBD modeling and (2) better understand the influence of surface fuels in this regard. Response variables included FuelCalc output and indirect estimates of maximum burnable fuel based on canopy gap fraction (CGF) measured at ground level and 2 m above ground level. Results SAR variables were important predictors of CBD and total fuel density (TFD) in all independent model calibrations with ground data, in which we define TFD as the sum of CBD and primarily live coniferous surface fuel density (SFD) 0 to 2 m above ground. Exploratory estimates of TFD appeared biased to the presence of sapling-stage conifer fuel on measures of CGF at the ground level. Thus, modeling efforts to calibrate SFD with satellite sensor data failed. Both CGF-based and FuelCalc-based field estimates of CBD yielded close unity with satellite-calibrated estimates, although substantial differences in data distributions existed. Estimates of CBD from the widest CGF zenith angle range (0 to 38°) correlated best with FuelCalc-based CBD estimates, while both resulted in maximum biomass values that exceeded those considered typical for the SNF. Model results from the narrowest zenith angle range (0 to 7°) produced estimates of CBD that were more in line with values considered typical. LANDFIRE’s estimates of CBD were weakly, but significantly (P = 0.05), correlated to both narrow- and wide-angle CGF-based estimates of CBD, but not with FuelCalc-based estimates. Conclusions The combined use of field estimates of CBD, based on indirect measures of CGF according to Keane et al. (Canadian Journal of Forest Research 35:724–739, 2005), with SAR and optical satellite sensor data demonstrates the potential of this method for mapping CBD in the Upper Midwest, USA. Results suggested that the presence of live, coniferous surface fuels neither confounds remote detection nor precludes mapping of CBD in this region using SAR satellite sensor data, as C- and L-band idiosyncrasies likely limit the visibility of these smaller understory fuels from space. Nevertheless, research using direct measures of burnable SFD for calibrations with SAR satellite sensor data should be conducted to more definitively answer this remote detection question, as we suspect substantial bias among measures of CGF from ground level when estimating SFD as the difference between TFD and CBD.

Fire Weather and Smoke Management

2000 ◽  
Author(s):  
C. David Whiteman
Keyword(s):  
Forest Canopy ◽  
Wildland Fire ◽  
Fire Suppression ◽  
Fire Behavior ◽  
Plant Succession ◽  
Fire Intensity ◽  
Rate Of Spread ◽  
Resource Managers ◽  
Insect Infestations ◽  
Ecological Objectives

Wildland fires consume large areas of forest and grasslands every year. Fires are described in terms of fire behavior, which includes rate of spread and fire intensity. A fire that spreads rapidly burns less of the available fuel per square unit of area than a fire that moves slowly and allows the flaming front a longer residence time. A fire with flames that reach only two feet above the ground produces less heat and is less destructive than an intense fire that crowns, that is, has long flames and burns at the top (i.e., crown) of the forest canopy (figure 13.1). Fire suppression activities are initiated when a wildfire threatens people, property, or natural areas that need protection. These activities include dropping water or chemicals on a fire and establishing a fire line around the fire. A fire line is a zone along a fire’s edge where there is little or no fuel available to the fire. Roads, cliffs, rivers, and lakes can be part of a fire line, or land can be cleared by firefighters. Backfires may be set within the fire line to burn toward the fire, widening the fire line and reducing the likelihood of the fire spreading beyond it (figures 13.2 and 13.3). Fires can cross a fire line if the intensity is high or if spotting occurs, that is, if the wind carries burning material (firebrands) beyond the fire and across the fire line (figure 13.4). A wildland fire can be very destructive, but it can also be beneficial and may be used by land resource managers to accomplish specific ecological objectives. For example, smaller fires can reduce the danger of a large catastrophic fire by burning off underbrush. Fire can also be used to prepare land for planting, to control the spread of disease or insect infestations, to benefit plant species that are dependent on fire, to influence plant succession, or to alter the nutrients in the soil. When a fire is used to manage land resources, it is called a prescribed fire.

Fire behavior in immature jack pine

1987 ◽  
Vol 17 (1) ◽  
pp. 80-86 ◽  
Author(s):  
B.J. Stocks
Keyword(s):  
Forest Fire ◽  
Fire Behavior ◽  
Jack Pine ◽  
Quantitative Prediction ◽  
Fire Intensity ◽  
Fire Weather ◽  
Strongly Correlated ◽  
Fire Weather Index ◽  
Rate Of Spread ◽  
Forest Fire Management

A series of experimental fires, each 0.4 ha in size, was conducted between 1975 and 1981 in an unthinned stand of immature jack pine (1948 origin) in central Ontario to gather quantitative fire behavior data for forest fire management purposes. Twelve fires were conducted over a broad range of burning conditions. Fire behavior and impact characteristics (i.e., rate of spread, fuel consumption, and frontal fire intensity) were found to be strongly correlated with fire weather severity as expressed through various component codes and indices of the Canadian Forest Fire Weather Index (FWI) System. This type of experimental fire information, along with wildfire data, is being used in the development of guidelines for quantitative prediction of fire behavior in major Canadian forest fuel types.

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