| Popis: |
Wildland fire behavior is highly dependent upon local meteorological conditions. While topography and the state of available fuels also influence fire behavior and spread, near-surface atmospheric conditions in proximity to wildland fires are the most dynamic determining variables for wildfire evolution. Recent episodes of drought across the southern High Plains have contributed to unprecedented wildfire activity in the region’s grasslands, including within the Texas Tech University West Texas Mesonet (WTM) domain. The juxtaposition of this meso-network with the occurrence of numerous wind-driven wildfires has provided a unique dataset of proximity meteorological observations useful in analyzing fire start environments. This study presents statistical analyses of WTM 2-m relative humidity and 6-m wind speed, parameters utilized in local Red Flag fire weather warning criteria, along with 2-m temperature in temporal and spatial proximity to 99 wind-driven grassland wildfire starts which occurred between January 2006 and May 2010. Since the state of vegetative fuels also influences fire behavior, but is dependent upon local weather, the proximity observations are used to calculate fine dead-fuel moisture and to examine pre-conditioning potential per the preceding humidity recoveries for each documented fire start. A comparison of the meteorological observations to local Red Flag warning criteria, which was met or exceeded for critical values of relative humidity and wind speed in 64% of the surveyed fire starts, also is included. Furthermore, seasonal and diurnal tendencies for local wind-driven wildfire activity are noted. |
