UC Riverside

Wildfires are common phenomena and most recently they are occurring at record breaking scale and intensity. In addition, the rapid expansion of human populations closer to the wildland has placed people and structures at risk when wildfires occur. In Southern California, wildfires are primarily fueled by chaparral shrubs. The chaparral fires are typically classified as crown fires, a dual layer type of wildfire composed of an elevated live fuel layer, known as crown layer, and a layer of dead fuel located above ground, called the surface fuel layer. Since the fire spread is typically most severe once it reaches the live crown fuels, understanding the conditions for the flame transition process from surface to crown is paramount. This presentation features work aiming to produce greater understanding of the processes via which chaparral crown fires ignite, transition and spread. To this purpose, a wind tunnel scale study was designed to assess the impact of wind speed and surface-crown fuel layer distance on fire behavior. It will be shown how different experimental parameters affect transition conditions, spread behavior and flame geometry. The regional scale study explores wildfire behavior and examines ways to deploy laboratory findings with the plethora of existing satellite data to derive data driven models of fire behavior. An effort to present fire science to the elementary school age students via physics-based video game will also be explained.