Accession Number : ADA267982


Title :   The Influence of Forest Fire Induced Albedo Differences on the Generation of Mesoscale Circulations


Descriptive Note : Master's thesis


Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH


Personal Author(s) : Knowles, John B


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a267982.pdf


Report Date : May 1993


Pagination or Media Count : 99


Abstract : The development of a mesoscale circulation by the thermal contrast between a fire burned area surrounded by untouched vegetation was simulated by the Regional Atmospheric Modeling System (RAMS) in order to show the circulation's ability to generate clouds and precipitation. The simulations used two fires that occurred during the summer of 1988. The first fire was over 400 square kilometers in size, while the second fire was over 100 square kilometers in size. Results of the 8-hour simulations showed that the thermal differences between the first fire burn area and surrounding unburned area generated a well- developed mesoscale circulation with a vertical updraft speed of over 3.5 m s-1. The simulation also developed clouds and precipitation directly above the circulation center. Simulation of the second fire burn area generated a mesoscale circulation with a vertical updraft speed of over 2.5 m s-1. Although the second simulation did develop clouds and some very light precipitation, it could not be directly tied to the mesoscale circulation itself.


Descriptors :   *ATMOSPHERIC MOTION , *FOREST FIRES , VELOCITY , MATHEMATICAL MODELS , SIMULATION , THERMAL STABILITY , LIGHTNING , ATMOSPHERIC PRECIPITATION , CIRCULATION , SUMMER , ALBEDO , CONVECTION(ATMOSPHERIC) , ATMOSPHERE MODELS , VEGETATION , CASE STUDIES , PRECIPITATION , CLOUDS , WIND , THESES


Subject Categories : Forestry
      Meteorology


Distribution Statement : APPROVED FOR PUBLIC RELEASE