Toward a UK fire danger rating system: Understanding fuels, fire behaviour and impacts

传统上，野火被视为仅限于南欧或澳大利亚等地区的威胁。然而，全球野火威胁正在扩大，近年来英国对野火危险的认识大幅增加。在2009年4月至2017年3月的八个财政年度中，仅在英格兰，消防和救援服务(FRS)就处理了超过25万起野火事件。个别事件在空间上范围广泛，具有挑战性(如Saddleworth Moor，2018年)，并威胁到财产、交通和其他基础设施，特别是在城乡交界处(如2011年4月/5月，斯温利森林)。据估计，仅英国每年应对植被火灾的费用就高达5500万英镑，其中个别大型事件的费用高达100万英镑。为应对重大火灾季节(如2003年和2011年)，“严重野火”已列入国家风险登记册，并建立了两个跨部门的国家野火论坛(英格兰和威尔士；苏格兰(与北爱尔兰))。这些举措证明，需要适当的基础科学理解和系统来管理和缓解当前和未来的英国野火威胁。最近的气候变化风险评估也强调了野火风险的增加。火灾危险是对影响野火在一个地区引发、蔓延和控制的恒定和可变因素的组合的描述。野火危险评级系统(WFDRS)旨在评估燃料和天气，以提供在这些条件下的易燃性和可能的火灾行为的估计。这些危险等级可以为土地管理者的管理决策提供信息，为FRS团队指导资源计划，并为地方和国家政府的战略规划提供信息。英国没有WFDRS，我们缺乏基本的科学和最终用户的理解，无法有效预测英国目前和未来气候和土地利用情景下发生野火事件的可能性、行为和影响。英格兰和威尔士有英国气象局火灾严重性指数系统(MOFSI)，由气象局仅根据天气预报运行，这一系统完全是为了确定是否应该按照《乡村和路权法案》(2000)所定义的那样，在火灾天气期间关闭开放土地。然而，在2018年英国干旱期间，MOFSI指数没有上升到足以引发遭受严重野火地区的土地关闭。此外，由于英国没有WFDRS，MOFSI背后的算法也被用来向自然灾害伙伴关系每日危险评估提供信息。对最近2018年极端火灾情况的麻木不仁表明，它无法适当地预先警告政府、应急人员和土地所有者。因此，我们需要为英国定制一个WFDRS。该项目将承担建立英国特有的WFDRS所需的基础科学和分析，并由将作为项目合作伙伴的关键利益攸关方提供信息。这必须是为英国燃料、其复杂的土地覆盖马赛克和基础设施以及不断变化的土地利用模式和气候而设计的。

Wildfires have traditionally been perceived as a threat confined to regions such as Southern Europe or Australia. However, the global wildfire threat is expanding and recognition of wildfire hazard in the UK has grown substantially in recent years. In the eight financial years between April 2009 and March 2017 over 250,000 wildfire incidents were dealt with by the Fire and Rescue Services (FRS) in England alone. Individual events have been spatially extensive, challenging to fight (e.g. Saddleworth Moor, 2018), and have threatened property, transport and other infrastructure, especially in the rural-urban interface (e.g. Swinley Forest, April/May 2011). Response costs alone for vegetation fires in Great Britain have been estimated at £55 million per year, with individual large scale events costing up to £1 million. In response to significant fire seasons (e.g. 2003 & 2011), 'severe wildfire' has been included on the National Risk Register and two cross-sector national Wildfire Forums have been established (England and Wales; Scotland (with Northern Ireland)). These initiatives evidence the need for appropriate fundamental scientific understanding and systems to manage and mitigate the current and future UK wildfire threat. The recent Climate Change Risk Assessment has also highlighted the increased risk of wildfires.Fire danger is a description of the combination of both constant and variable factors that affect the initiation, spread, and ease of controlling a wildfire on an area. Wildfire Danger Rating Systems (WFDRS) are designed to assess the fuel and weather to provide estimates of flammability and likely fire behaviour under those conditions. These danger ratings can inform management decisions for land managers, direct resourcing plans for FRS teams, and feed into strategic planning for local and national governments. The UK does not have a WFDRS and we lack the fundamental scientific and end-user understanding to effectively predict the likelihood, behaviour and impact of wildfire incidents in the UK for present and future climate and land use scenarios. England and Wales has the Met Office Fire Severity Index system (MOFSI) operated by the Met Office based on weather forecasts only and this is solely designed to determine if open access land should be closed as defined in the Countryside and Rights of Way Act (2000) during 'exceptional' fire weather. However, during the 2018 UK drought MOFSI indices did not rise sufficiently to trigger land closures in areas that suffered severe wildfires. Additionally, due to the absence of a WFDRS in the UK, the algorithms underlying MOFSI are also used to inform the Natural Hazard Partnership Daily Hazard Assessment. The insensitivity to recent extreme fire conditions of 2018 are indicative of its inability to properly forewarn government, responders and land owners. We therefore need a bespoke WFDRS for the UK. This project will undertake the fundamental science and analyses required for building a UK-specific WFDRS, informed by key stakeholders who will act as project partners. This must be designed for UK fuels, its complex land cover mosaics and infrastructure, and changing land use patterns and climate.