气候变化领域集成服务门户(CCPortal): Modeling the global radiative effect of brown carbon: A potentially larger heating source in the tropical free troposphere than black carbon

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DOI	10.5194/acp-20-1901-2020
	Modeling the global radiative effect of brown carbon: A potentially larger heating source in the tropical free troposphere than black carbon
	Zhang A.; Wang Y.; Zhang Y.; Weber R.J.; Song Y.; Ke Z.; Zou Y.
发表日期	2020
ISSN	16807316
起始页码	1901
结束页码	1920
卷号	20 期号:4
英文摘要	Carbonaceous aerosols significantly affect global radiative forcing and climate through absorption and the scattering of sunlight. Black carbon (BC) and brown carbon (BrC) are light-absorbing carbonaceous aerosols. The direct radiative effect (DRE) of BrC is uncertain. A recent study suggests that BrC absorption is comparable to BC in the upper troposphere over biomass burning regions and that the resulting radiative heating tends to stabilize the atmosphere. Yet current climate models do not include proper physical and chemical treatments of BrC. In this study, we derived a BrC global biomass burning emission inventory on the basis of the Global Fire Emissions Database version 4 (GFED4), developed a module to simulate the light absorption of BrC in the Community Atmosphere Model version 5 (CAM5) of the Community Earth System Model (CESM), and investigated the photobleaching effect and convective transport of BrC on the basis of Studies of Emissions, Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys (SEAC4RS) and Deep Convective Clouds and Chemistry Project (DC3) measurements. The model simulations of BC were also evaluated using HIAPER (High- Performance Instrumented Airborne Platform for Environmental Research) Pole-to-Pole Observations (HIPPO) measurements. We found that globally BrC is a significant absorber, the DRE of which is 0.10Wm-2, more than 25% of BC DRE (+39Wm-2). Most significantly, model results indicated that BrC atmospheric heating in the tropical mid and upper troposphere is larger than that of BC. The source of tropical BrC is mainly from wildfires, which are more prevalent in the tropical regions than higher latitudes and release much more BrC relative to BC than industrial sources. While BC atmospheric heating is skewed towards the northern midlatitude lower atmosphere, BrC heating is more centered in the tropical free troposphere. A possible mechanism for the enhanced convective transport of BrC is that hydrophobic high molecular weight BrC becomes a larger fraction of the BrC and less easily activated in a cloud as the aerosol ages. The contribution of BrC heating to the Hadley circulation and latitudinal expansion of the tropics is likely comparable to BC heating. © 2020 American Institute of Physics Inc.. All rights reserved.
关键词	aerosol biomass burning black carbon brown carbon climate modeling emission inventory heating modeling radiative forcing troposphere
语种	英语
来源机构	Atmospheric Chemistry and Physics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/132229
推荐引用方式 GB/T 7714	Zhang A.,Wang Y.,Zhang Y.,et al. Modeling the global radiative effect of brown carbon: A potentially larger heating source in the tropical free troposphere than black carbon[J]. Atmospheric Chemistry and Physics,2020,20(4).
APA	Zhang A..,Wang Y..,Zhang Y..,Weber R.J..,Song Y..,...&Zou Y..(2020).Modeling the global radiative effect of brown carbon: A potentially larger heating source in the tropical free troposphere than black carbon.,20(4).
MLA	Zhang A.,et al."Modeling the global radiative effect of brown carbon: A potentially larger heating source in the tropical free troposphere than black carbon".20.4(2020).