T/F Topography can directly and indirectly affect fuels and their availability for combustion. - Answer - True Of the three primary environmental factors that influence fire behavior, which is the least variable? - Answer - Topography The least critical form of heat transfer that influences rate of spread in a running wild land fire is: - Answer - Conduction The point to which a combustible material must be heated to produce self-sustaining combustion is known as the: - Answer - Ignition temperature Fireline intensity is dependent upon: - Answer - All of the above. Fuel size Fuel moisture Fuel temperature Fuel compactness and arrangement T/F Two requirements for long range spotting are wind and a well developed convection column. - Answer - True A fire that advances through canopies of brush and trees is known as a: - Answer - Crown fire Fire is burning in litter on top of the ground, but occasionally carries into the crowns of individual trees, which produces burning embers that start new fires outside the fire perimeter. - Answer - Surface fire with torching and spotting. This study source was downloaded by 100000887544919 from CourseHero.com on 07-14-2024 11:15:07 GMT -05:00 https://www.coursehero.com/file/226214955/S-290-Final-Exam-Questions-Verified-Answers-Graded-A-Latest-2024docx/ Fire begins burning into the crowns and spreads through the canopy. There is a sudden increase in fireline intensity where the fire controls it's environment. At one point flames can be seen carried high into the convection column with a whirling motion. - Answer - Ground fire with smoldering and flare ups. T/F Upward moving air contracts and warms. - Answer - False As air sinks, it. - Answer - Increases in pressure, warms and compresses. Why do dry climates usually have lower nighttime temperatures than humid climates? - Answer - Because there is less water vapor in the air to absorb and reflect heat back to the surface at night. T/F On average the RH doubles with each 20F decrease of temperature, or halves with each 20F increase in temperature. - Answer - True T/F The lowest RH occurs with the highest temperature. - Answer - True T/F RH is usually lower on north aspects. - Answer - False T/F Cloudiness has little affect on relative humidity and temperature. - Answer - False T/F The type of vegetation has little affect on temperature and humidity. - Answer - False T/F RH measures the amount of moisture in the air. - Answer - True S/U Clouds form in layers. - Answer - Stable S/U Gusty winds - Answer - Unstable S/U Smoke column spreads out after limited rise. - Answer - Stable S/U Clouds grow vertically - Answer - Unstable S/U Firebrands are lifted into convection column. - Answer - Unstable T/F Temperature decreases with an increase in elevation when an inversion is present. - Answer - False What is the general effect of stable air on wild land fires? - Answer - Fire activity decreases What conditions will occur under a surface inversion during the morning hours? - Answer - All of the above Temperatures are cool, winds are calm or light