Collaborative Research: Measurement and Modeling of Brown Carbon (BrC) from Boreal Forest Wildfires in Alaska

该项目的重点是表征北极生物质燃烧产生的棕色碳（BrC）的排放、光学特性和辐射影响。假设北极的BrC是不同的，因为北方森林火灾往往是阴燃的，这是由于地下生物量的大量消耗，以及北极气溶胶的光化学处理较慢，这是由于平流层臭氧对紫外线的强烈吸收（光路较长）。对北极地区发现的BrC特性的进一步了解将使化学传输模型能够更好地评估北方森林火灾中BrC的直接辐射影响。研究将集中在三个方面：(1)北方森林火灾中BrC的发射和光学特性；(2)北极地区有机气溶胶和黑碳的排放和物理性质；(3)北极生物质燃烧对地表辐射收支的影响。该项目包括度量和建模组件。本项目收集的数据将与在北极设有站点的两个长期监测网络——改进网络和化学物种形成网络——的数据进行比较。该项目的结果将与位于阿拉斯加费尔班克斯大学的阿拉斯加火灾科学联盟共享，以帮助将结果传播给该州的跨部门火灾管理社区。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This project is focused on characterizing the emissions, optical properties and radiative impacts of brown carbon (BrC) from biomass burning in the Arctic. The hypothesis is that BrC in the Arctic is different because boreal forest fires tend to be smoldering due to the large consumption of below-ground biomass, and the photochemical processing of aerosol in the Arctic is slower due to the strong UV absorption by stratospheric ozone (longer light path). The improved understanding of the properties of BrC found in the Arctic will enable chemical transport modeling to better assess the direct radiative effects of BrC from boreal forest fires.The research will focus on three topics: (1) the emissions and optical properties of BrC from boreal forest fires; (2) the emissions and physical properties of organic aerosol and black carbon in the Arctic; and (3) the influence of Arctic biomass burning on the radiative budget at the surface. The project includes both a measurement and a modeling component. Data collected in this project data will be compared with that from two long-term monitoring networks with sites in the Arctic, the IMPROVE network and the Chemical Speciation Network. The results of the project will be shared with the Alaska Fire Science Consortium, based at University of Alaska Fairbanks, to help disseminate the results to the interagency fire management community in the state.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.