Gustiness and its influence on wildfire

自1999年以来，在美国林务局的支持下，我与犹他州大学和国家标准与技术研究所的同事开发了两种不同的数值工具来研究野火行为。第一个是一个简单的操作野火行为和野火蔓延率模型与3维，非流体静力学，云解析数值预报模型，解决了火灾对流和周围的大气，燃料和地形之间的相互作用的耦合。第二个是一个耦合的流体动力学数值有效的模型来预测当地的空气流动和烟雾产生与大气传输/野火行为模型的基础上的质量，动量和能量守恒的原则，对待火灾燃烧在一个更物理的方式，而不是基于经验和规定的配方，表征当前的操作野火模型。我们计划使用这两种工具来建立什么过程决定表面阵风和表面阵风如何影响荒地火灾行为。 阵风的确定是重要的火灾天气预报，特别是对于严重的荒地火灾事件，和阵风有影响的荒地火灾管理的许多方面。风阵风，例如，影响表演和设计的禁止烧伤。 当阵风超过给定阈值时，由于风引起的严重和不稳定的火灾行为，可以预期非常危险和不可控制的火灾行为。 一个准确的估计是非常宝贵的，以防止或限制由于突然严重的火灾行为的危险，并帮助组织荒地消防队员的安全援助。我们强调，通过使用这些数值工具，我们可以第一次研究野火行为，燃烧和烟雾的许多不同方面的演变，在多个尺度下，并在受控条件下。

Since 1999 I have, with the support of the US Forest Service, and colleagues at the University of Utah and the National Institute for Standards and Technology, developed two different numerical tools for studying wildfire behavior. The first is a coupling of simple operational wildfire behavior and wildfire spread rate models with a 3-dimensional, non-hydrostatic, cloud-resolving numerical prediction model, that resolves the interactions between convection from the fire and the surrounding atmosphere, fuel, and topography. The second is a coupling of a hydrodynamical numerically efficient model to predict local air flow and smoke production with an atmospheric transport/wildfire behavior model based on the principals of conservation of mass, momentum, and energy, that treats fire combusion in a more physical fashion, and not based on the empirical and prescribed formulations that characterize current operational wildfire models. We plan to use both these tools to to establish what processes determine surface wind gusts and how surface wind gustiness influences wildland fire behavior.  Determination of wind gusts is important to fire weather forecasting, especially for severe wildland fire events, and gustiness has implications for many aspects of wildland fire management. Wind gustiness, for instance, influences the performing and design of perscribed burns.  When gusts exceed a given threshold, very dangerous and uncontrollable fire behavior can be expected due to wind-induced severe and erratic fire behavior.  An accurate estimate is invaluable to prevent or limit the danger due to sudden severe fire behavior, and an aid to help organize the safety of wildland fire fighters. We emphasize that by using these numerical tools we can study for the first time the evolution of many different aspects of wildfire behavior, combustion, and smoke, at multiple scales, and under controlled conditions.