Forest fire regimes across boreal Eastern North America and Northern Europe (BENANE): towards understanding long-term dynamics, climate drivers, and future trends of forest fire activity

火驱动着北方森林的动态和生态系统功能，并直接影响全球碳平衡和大气痕量气体的浓度。了解火灾活动的多尺度控制对于合理地模拟该生物群过去和未来的动态，特别是它对未来气候变化的反应是至关重要的。我的研究的主要长期目标是有助于理解作为生物地理和气候因素的函数的环北方火灾活动的长期动态。这一知识应当能够对未来的火灾活动进行合理的建模，特别是将大规模大气环流模式缩小到对未来森林火灾活动的估计中，并评估北方生物群在一系列气候条件下的复原力。拟议的项目侧重于北美东部和北欧(BENANE)的北方森林，这项研究的进展在很大程度上受到以下因素的限制：(A)缺乏足够的参考数据集；(B)对复杂的气候--火灾联系的了解有限。拟议的项目将：(A)一方面建立气候变异性、分区域生物地理和火灾活动区域模式之间的机械关系，另一方面特别侧重于整个贝纳内地区火灾活动增加的年份和时期，(B)校准一个基于过程的建模框架，以预测和分析未来气候对贝纳内火灾活动的影响，包括碳排放动态、植被组成和动态变化、森林碳平衡以及森林生物量和生产力。我的总体假设是，尽管贝宁境内的生物地理差异，主要干扰事件类型(地表和林下替代火灾)的差异，以及所考虑的大地理尺度，但次区域火灾活动存在强烈的遥相关模式，可以在多个时间尺度上回顾观察到这种模式。这种连通性源于本纳岛上空的大范围大气环流异常，这与涉及北大西洋的系统能量状态的变化和相关的大气压力模式有关。

Fire drives the dynamics and ecosystem functions of the boreal forest and directly affects global carbon balance and concentrations of the atmospheric trace gases. Understanding multi-scale controls of fire activity is paramount for sound mechanistic modeling of past and future dynamics of this biome, and particularly - its response to future climatic changes. The main long-term objective of my research is to contribute towards understanding of long-term dynamics of circumboreal fire activity as a function of biogeographical and climatic factors. This knowledge should allow for sound modelling of the future fire activity, and specifically - in downscaling the large-scale atmospheric circulation patterns into estimates of future forest fire activity and assessing the resilience of the boreal biome under a range of climate conditions. The proposed project focuses on the boreal forests of Eastern North America and Northern Europe (BENANE), where the progress in this research is largely limited by (a) the availability of adequate reference datasets, and (b) limited understanding of complex climate-fire linkages. The proposed project will (A) establish a mechanistic relationship between climate variability, sub-regional biogeography, on one hand, and regional patterns of fire activity, on the other, putting a particular focus on years and periods with increased fire activity across BENANE region, and (B) calibrate a process-based modeling framework to project and analyze the effects of future climate on fire activity in BENANE, including dynamics of carbon emissions, changes in composition and dynamics of vegetation, forest carbon balance, and forest biomass and productivity. My overall hypothesis is that despite biogeographical differences within BENANE, differences in the dominating type of disturbance events (surface vs. stand replacing fires) and large geographical scale under consideration, there is a strong teleconnectivity patterns in sub-regional fire activity, which could be observed restrospecitvely at multiple temporal scales. This connectivity stems from large scale atmospheric circulation anomalies over the BENANE, which are related to the changes in the energy states of the system involving Northern Atlantic Ocean and associated atmospheric pressure patterns.