Collaborative Research: Fire at the Intersection of Global Carbon and Water Cycles

对森林和野火对大气碳排放预算的贡献的现有估计可能高达全球年度化石燃料碳排放的40%。气候变化情景，例如在美国西部大陆等火灾多发地区，表明春季和夏季气温上升，通过较短的积雪融化时间减少水分，这可能导致更长的野火季节在越来越大的地区发生作用。在这项由多学科研究小组开展的工作中提出的前提是，火可能在陆地碳和水循环之间调解几个重要的反馈，但尚未在碳-气候耦合模型中认真考虑。除了降水、干旱、土壤湿度对火灾影响的直接调节，以及从土地利用变化、森林砍伐、牧场维护和农业实践在内的一系列人类活动，还将审查以碳和水循环为中心的一系列生物地球化学和生态系统反馈。这项工作的方法是在国家大气研究中心(NCAR)维护和开发的社区气候系统模型(CCSM)共同土地模型碳和氮(CLM-CN)模型的具体框架内，改进对火灾和与火灾有关的过程的描述。除了在实现几个建模目标方面取得进展外，这一努力还将结合一些教育活动、方案和研讨会，明确旨在为未来的政府间气候变化专门委员会(IPCC)评估做出贡献。这项工作得到了美国国家科学基金会地球系统碳和水征集项目的支持，这是地球科学局提供的跨学科资助机会。

Available estimates of the contribution of forest and wildfires on atmospheric carbon emission budgets may be as high as 40% of the global annual fossil fuel carbon emissions. Climate change scenarios, for example in fire prone regions such as the western continental United States, suggest elevated spring and summertime temperatures, reduced moisture through shorter snowpack melt duration which may lead to longer wildfire seasons acting over increasingly large areas. The premise advanced in this work to be conducted by a multi-disciplinary team of investigators is that fire may mediate several important feedbacks between the terrestrial carbon and water cycles, yet has not yet been seriously considered in coupled carbon-climate models. As well as the direct modulation of fire effects by precipitation, drought, soil moisture, together with a host of human activities ranging from land use changes, deforestation, pasture maintenance and agricultural practice, a range of biogeochemical and ecosystem feedbacks centered on the carbon and water cycles will be examined. The approach of this effort is to improve the representation of fire and fire-related processes within the specific framework of the Community Climate System Model (CCSM) Common Land Model Carbon and Nitrogen (CLM-CN) model, maintained and developed at the National Center for Atmospheric Research (NCAR). As well as progress towards achieving several modeling objectives, this effort will combine a number of educational activities, programs and workshops with an explicit intent of contributing to future IPCC (Intergovernmental Panel on Climate Change) assessments. This work is supported under the NSF Carbon and Water in the Earth System solicitation, an interdisciplinary funding opportunity from the Directorate of Geosciences.