Fire weather and lightning fires in a changing climate

野火在加拿大是一种常见的现象，在过去的十年中，每年平均有8000起火灾烧毁200万公顷土地。这一地区的大部分烧毁的结果，林更新高强度冠火灾。 这些高强度的火灾可能对社区产生重大影响;例如，2011年的奴湖和2003年的基洛纳火灾造成的损失高达数亿美元。 这项研究将集中在三个相关的研究，检查火灾天气，燃料水分，闪电，火灾发生预测和气候变化。这些研究的目的是：1）开发一种混合方法，利用气象站、雷达和闪电活动，通过气象站观测值、闪电活动水平（作为降水的替代）和降水雷达数据，2）开发和确定加拿大1-3天闪电预报模型的准确性，（3）为加拿大开发一个1-3天的闪电火灾发生预测系统，然后使用该预测系统沿着未来气候的一般环流模式来估计21世纪剩余时间的闪电和闪电火灾发生。 火灾天气的最大挑战之一是确定气象站之间的天气状况，特别是降水的位置和数量。在火灾季节，大部分降水是对流性质的;阵雨和雷阵雨在空间和时间上变化很大。加拿大火灾天气指数系统中的燃料湿度是通过对温度、降水、风速和相对湿度的观测来确定的。在这个时候，我们只解决降水，因为它是最大的不确定性的来源时，计算燃料水分和火灾危险的景观。我们将根据天气观测、雷达和闪电活动改进降水量估计。 闪电引起的火灾发生预测模型已经存在多年，大多数模型使用过去24小时观察到的闪电活动和观察到的燃料湿度来估计火灾发生。未来一两天的预报是可能的，但这些预报是针对延滞火灾（在地下闷烧，但在天气条件有利之前不会发展为火焰燃烧的火灾），基于观测到的闪电和来自天气预报的预测燃料水分。 目前的方法是有限的，因为它不考虑额外的闪电在火灾发生预测。将为加拿大开发一个为期三天的闪电预报模型。 将为加拿大开发一个闪电引起的火灾发生预测系统。使用这个火灾发生预测系统和三天闪电预报模型沿着与大气环流模型数据，我们将模拟闪电和闪电引起的火灾发生为21世纪世纪的其余部分。 拟议的工作将推动火灾研究的进步，从而为日常火灾管理活动带来有意义的变化，这将有助于保护加拿大人和我们的社区。

Wildland fire is a common occurrence in Canada with 8000 fires burning 2 million hectares on average every year during the past decade. Most of this area burned results from stand-renewing high-intensity crown fires. These high intensity fires can have significant impact on communities; for example, the fires in Slave Lake in 2011 and Kelowna in 2003 sustained damages measured in 100s of millions of dollars. This research will focus on three related studies examining fire weather, fuel moisture, lightning, fire occurrence prediction and climate change. The objectives of these studies are to: 1) develop a blended method using weather stations, radar and lightning activity to estimate total storm precipitation across the landscape through the interpolation of weather stations observations, the level of lightning activity ( as a proxy for precipitation) and precipitation radar data, 2) develop and determine the accuracy of a 1-3 day lightning forecast model for Canada, and 3) develop a 1-3 day lightning-caused fire occurrence prediction system for Canada and then use this prediction system along with General Circulations Models of future climate to estimate the lightning and the lightning – caused fire occurrence for the rest of the 21st century. One of the largest challenges with the fire weather is determining the weather conditions between weather stations and in particular the location and amount of precipitation. During the fire season much of the precipitation is convective in nature; showers and thundershowers that are highly variable in space and time. Fuel moisture in the Canadian Fire Weather Index System is determined by observations of temperature, precipitation, wind speed and relative humidity. At this time, we are addressing only precipitation because it is the source of the largest uncertainty when calculating fuel moisture and fire danger across the landscape. We will develop improved precipitation estimates from the weather observations, radar and lightning activity. Lightning-caused fire occurrence prediction models have been available for years and most models use observed lightning activity from the last 24 hours and observed fuel moisture to estimate fire starts. Forecasts for the next day or two are possible but these forecasts are for hold-over fires (fires that smoulder underground but don’t progress to flaming combustion until the weather conditions are conducive) based on the observed lightning and forecasted fuel moisture derived from weather forecasts. This current approach is limited as it does not consider additional lightning in the fire occurrence prediction. A three day lightning forecast model will be developed for Canada. A lightning-caused fire occurrence prediction system will be developed for Canada. Using this fire occurrence prediction system and the three day lightning forecast model along with General Circulation Model data we will model lightning and lighting-caused fire occurrence for the rest of the 21st century. The proposed work will lead to advances in fire research that will result in meaningful changes in day-to-day fire management activities that will help protect Canadians and our communities.