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DOI	10.5194/acp-19-1685-2019
	Biomass-burning smoke heights over the Amazon observed from space
	Gonzalez-Alonso L.; Martin M.V.; Kahn R.A.
发表日期	2019
ISSN	16807316
起始页码	1685
结束页码	1702
卷号	19 期号:3
英文摘要	We characterise the vertical distribution of biomass-burning emissions across the Amazon during the biomass-burning season (July-November) with an extensive climatology of smoke plumes derived from MISR and MODIS (2005-2012) and CALIOP (2006-2012) observations. Smoke plume heights exhibit substantial variability, spanning a few hundred metres up to 6 km above the terrain. However, the majority of the smoke is located at altitudes below 2.5 km. About 60 % of smoke plumes are observed in drought years, 40 %-50 % at the peak month of the burning season (September) and 94 % over tropical forest and savanna regions, with respect to the total number of smoke plume observations. At the time of the MISR observations (10:00-11:00 LT), the highest plumes are detected over grassland fires (with an averaged maximum plume height of ∼1100 m) and the lowest plumes occur over tropical forest fires (∼800 m). A similar pattern is found later in the day (14:00-15:00 LT) with CALIOP, although at higher altitudes (2300 m grassland vs. 2000 m tropical forest), as CALIOP typically detects smoke at higher altitudes due to its later overpass time, associated with a deeper planetary boundary layer, possibly more energetic fires, and greater sensitivity to thin aerosol layers. On average, 3 %-20 % of the fires inject smoke into the free troposphere; this percentage tends to increase toward the end of the burning season (November: 15 %-40 %). We find a well-defined seasonal cycle between MISR plume heights, MODIS fire radiative power and atmospheric stability across the main biomes of the Amazon, with higher smoke plumes, more intense fires and reduced atmospheric stability conditions toward the end of the burning season. Lower smoke plume heights are detected during drought (800 m) compared to non-drought (1100 m) conditions, in particular over tropical forest and savanna fires. Drought conditions favour understory fires over tropical forest, which tend to produce smouldering combustion and low smoke injection heights. Droughts also seem to favour deeper boundary layers and the percentage of smoke plumes that reach the free troposphere is lower during these dry conditions. Consistent with previous studies, the MISR mid-visible aerosol optical depth demonstrates that smoke makes a significant contribution to the total aerosol loading over the Amazon, which in combination with lower injection heights in drought periods has important implications for air quality. This work highlights the importance of biome type, fire properties and atmospheric and drought conditions for plume dynamics and smoke loading. In addition, our study demonstrates the value of combining observations of MISR and CALIOP constraints on the vertical distribution of smoke from biomass burning over the Amazon. © 2019 Author(s).
语种	英语
scopus关键词	aerosol; atmospheric chemistry; biomass burning; boundary layer; CALIOP; climatology; MISR; MODIS; smoke; vertical distribution; Amazonia
来源期刊	Atmospheric Chemistry and Physics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/144658
作者单位	Chemical and Biological Engineering Department, University of Sheffield, United Kingdom; Leverhulme Centre for Climate Change Mitigation, Animal Plant Sciences Department, University of Sheffield, United Kingdom; Climate and Radiation Laboratory, Code 613, NASA Goddard Space Flight Center, United States
推荐引用方式 GB/T 7714	Gonzalez-Alonso L.,Martin M.V.,Kahn R.A.. Biomass-burning smoke heights over the Amazon observed from space[J],2019,19(3).
APA	Gonzalez-Alonso L.,Martin M.V.,&Kahn R.A..(2019).Biomass-burning smoke heights over the Amazon observed from space.Atmospheric Chemistry and Physics,19(3).
MLA	Gonzalez-Alonso L.,et al."Biomass-burning smoke heights over the Amazon observed from space".Atmospheric Chemistry and Physics 19.3(2019).