气候变化领域集成服务门户(CCPortal): Exploring the elevated water vapor signal associated with the free tropospheric biomass burning plume over the southeast Atlantic Ocean

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DOI	10.5194/acp-21-9643-2021
	Exploring the elevated water vapor signal associated with the free tropospheric biomass burning plume over the southeast Atlantic Ocean
	Pistone K.; Zuidema P.; Wood R.; Diamond M.; Da Silva A.M.; Ferrada G.; Saide P.E.; Ueyama R.; Ryoo J.-M.; Pfister L.; Podolske J.; Noone D.; Bennett R.; Stith E.; Carmichael G.; Redemann J.; Flynn C.; Leblanc S.; Segal-Rozenhaimer M.; Shinozuka Y.
发表日期	2021
ISSN	1680-7316
起始页码	9643
结束页码	9668
卷号	21 期号:12
英文摘要	In southern Africa, widespread agricultural fires produce substantial biomass burning (BB) emissions over the region. The seasonal smoke plumes associated with these emissions are then advected westward over the persistent stratocumulus cloud deck in the southeast Atlantic (SEA) Ocean, resulting in aerosol effects which vary with time and location. Much work has focused on the effects of these aerosol plumes, but previous studies have also described an elevated free tropospheric water vapor signal over the SEA. Water vapor influences climate in its own right, and it is especially important to consider atmospheric water vapor when quantifying aerosol-cloud interactions and aerosol radiative effects. Here we present airborne observations made during the NASA ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS) campaign over the SEA Ocean. In observations collected from multiple independent instruments on the NASA P-3 aircraft (from near-surface to 6-7gkm), we observe a strongly linear correlation between pollution indicators (carbon monoxide (CO) and aerosol loading) and atmospheric water vapor content, seen at all altitudes above the boundary layer. The focus of the current study is on the especially strong correlation observed during the ORACLES-2016 deployment (out of Walvis Bay, Namibia), but a similar relationship is also observed in the August 2017 and October 2018 ORACLES deployments. Using reanalyses from the European Centre for Medium-Range Weather Forecasts (ECMWF) and Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2), and specialized WRF-Chem simulations, we trace the plume-vapor relationship to an initial humid, smoky continental source region, where it mixes with clean, dry upper tropospheric air and then is subjected to conditions of strong westward advection, namely the southern African easterly jet (AEJ-S). Our analysis indicates that air masses likely left the continent with the same relationship between water vapor and carbon monoxide as was observed by aircraft. This linear relationship developed over the continent due to daytime convection within a deep continental boundary layer (up to g1/45-6gkm) and mixing with higher-altitude air, which resulted in fairly consistent vertical gradients in CO and water vapor, decreasing with altitude and varying in time, but this water vapor does not originate as a product of the BB combustion itself. Due to a combination of conditions and mixing between the smoky, moist continental boundary layer and the dry and fairly clean upper-troposphere air above (g1/46gkm), the smoky, humid air is transported by strong zonal winds and then advected over the SEA (to the ORACLES flight region) following largely isentropic trajectories. Hybrid Single-Particle Lagrangian Integrated Trajectory model (HYSPLIT) back trajectories support this interpretation. This work thus gives insights into the conditions and processes which cause water vapor to covary with plume strength. Better understanding of this relationship, including how it varies spatially and temporally, is important to accurately quantify direct, semi-direct, and indirect aerosol effects over this region. © Author(s) 2021.
语种	英语
scopus关键词	aerosol composition; aerosol formation; atmospheric plume; biomass burning; carbon emission; satellite data; stratocumulus; troposphere; water vapor; Atlantic Ocean; Atlantic Ocean (Southeast); Namibia
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/246780
作者单位	Bay Area Environmental Research Institute, Moffett Field, CA, United States; NASA Ames Research Center, Moffett Field, CA, United States; Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, United States; Department of Atmospheric Sciences, University of Washington, Seattle, WA, United States; NASA Goddard Space Flight Center, Greenbelt, MD, United States; Center for Global and Regional Environmental Research, The University of Iowa, Iowa City, IA, United States; Department of Atmospheric and Oceanic Sciences, University of California Los Angeles, Los Angeles, CA, United States; Institute of the Environment and Sustainability, University of California Los Angeles, Los Angeles, CA, United States; Science and Technology Corporation, Moffett Field, CA, United States; Department of Physics, University of Auckland, Auckland, New Zealand; College of Earth, Ocean and Atmospheric Sciences, Oregon State UniversityOR, United States; School of Meteorology, University of Oklahoma, Nor...
推荐引用方式 GB/T 7714	Pistone K.,Zuidema P.,Wood R.,et al. Exploring the elevated water vapor signal associated with the free tropospheric biomass burning plume over the southeast Atlantic Ocean[J],2021,21(12).
APA	Pistone K..,Zuidema P..,Wood R..,Diamond M..,Da Silva A.M..,...&Shinozuka Y..(2021).Exploring the elevated water vapor signal associated with the free tropospheric biomass burning plume over the southeast Atlantic Ocean.ATMOSPHERIC CHEMISTRY AND PHYSICS,21(12).
MLA	Pistone K.,et al."Exploring the elevated water vapor signal associated with the free tropospheric biomass burning plume over the southeast Atlantic Ocean".ATMOSPHERIC CHEMISTRY AND PHYSICS 21.12(2021).