Fire-Mediated Changes in the Arctic System: Interactions of Changing Climate and Human Activities

也许人类面临的最紧迫挑战是了解决定区域系统复原力极限的因素，这些系统在生物物理和社会驱动因素方面正在发生方向性变化。这项研究计划将记录火灾的变化，特别是人类活动对北极气候系统及其人类居民的影响。研究将集中在阿拉斯加和育空地区，这是一个大的区域系统，其中火灾是主要的干扰机制。拟议的研究在几个层面上具有智力价值：1。它将评估人类活动在阿拉斯加-育空地区火灾状况中不断变化的作用，因为这是由人对火灾的影响（点火和灭火）以及火灾对人的影响（包括经济影响）的变化决定的（例如，工资、财产风险）和生态系统服务（例如，游戏，浆果，木柴，木材，气候反馈）。2.它将评估气候和人类引起的火灾状况变化对对气候十分重要的陆地表面特性的影响。这是人类层面研究与气候反馈研究之间的关键联系。3.它将记录阿拉斯加-育空地区气候反馈的过去和未来可能发生的变化，这些变化是由气候变暖以及气候和人类引起的火灾状况变化造成的。它将比较（a）微量气体通量与水/能量交换和（B）北极与北方景观对大气加热的贡献。这是第一次比较北极内外人类活动对北极气候系统的作用。 这项研究对评估社区和道路附近当前灭火政策的短期和长期后果具有广泛的影响。北美的火灾管理目前正在努力解决与荒地-城市界面有关的问题。这种建模工作是第一个明确表示动态景观火灾演替模型中的抑制的工作之一，并将提供一种管理工具，用于评估不同火灾管理策略的后果（即，反应性与预防性）用于当前和未来的火灾状态。由于消防工资在农村社区经济中的重要性，这对维持生计活动的可持续性产生了影响。它还将评估北方地区以外的人类活动造成的总体气候反馈（全球变暖），并与人类与北方地区火灾状况相互作用造成的影响进行比较。由于火灾引起的植被变化可能是少数几个大的负反馈高纬度变暖，火灾管理提供了一个潜在的工具，以减轻这种变暖。然而，这一缓解战略的效用取决于火灾对气候和人类福祉的净影响。这项研究是第一次尝试评估这种激进的区域规模的努力，以减少高纬度气候变暖的潜在影响。这项研究通过整合自然科学和社会科学，并将当地居民纳入我们的研究团队，加强了跨学科研究。这些都是将人类层面研究有效纳入北极系统科学的重要步骤。

Perhaps the most urgent challenge facing humanity is to understand the factors determining the limits to resilience of regional systems that are changing directionally in biophysical and social drivers. This research program will document the changing role of fire, particularly as affected by human activities, on the Arctic Climate System and its human residents. The research will focus on Alaska and Yukon Territory, a large regional system in which fire is the dominant disturbance mechanism. The proposed research has intellectual merit at several levels: 1. It will assess the changing role of human activities in the fire regime of the Alaska- Yukon region as this is determined by changes in the effects of people on fire (ignition and suppression) and the effects of fire on people, including economics (e.g., wages, property risk) and ecosystem services (e.g., game, berries, firewood, timber, climate feedbacks). 2. It will evaluate the consequences of climate- and human-induced changes in fire regime on land-surface properties that are important to climate. This is a critical link between research on human dimensions and research on climate feedbacks. 3. It will document the past and plausible future changes in climate feedbacks in the Alaska-Yukon region that result from climate warming and from climate- and human- induced changes in fire regime. It will compare the contribution to atmospheric heating that comes from (a) trace-gas fluxes vs. water/energy exchange and (b) arctic vs. boreal landscapes. This is the first comparison of the role of human activities within and outside the Arctic on the Arctic Climate System. This research has broad implications for assessment of both the short- and long-term consequences of the current policy of fire suppression near communities and roads. Fire management in North America is currently struggling with issues related to the wildland-urban interface. This modeling effort is one of the first to explicitly represent suppression in a dynamic landscape fire succession model and will provide a management tool for assessing the consequences of different fire management strategies (i.e., reactive versus preventative) for present and future fire regimes. Because of the importance of fire-fighting wages in the economy of rural communities, this has implications for the sustainability of subsistence activities. It will also assess the overall climate feedbacks caused by human activities outside northern regions (global warming) as compared to effects resulting from human interactions with the fire regime of northern regions. Because fire-induced changes in vegetation may be one of the few large negative feedbacks to high-latitude warming, fire management provides a potential tool to mitigate this warming. The utility of this mitigation strategy depends, however, on the net effects of fire on climate and on human welfare. This study is the first attempt to assess the potential impacts of such a radical regional-scale effort to reduce high-latitude climate warming. This research enhances interdisciplinary research by integrating natural and social sciences and including local residents in our research team. These are important steps in effective inclusion of human-dimensions research in Arctic System Science.