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Title: Surface and free tropospheric sources of methanesulfonic acid over the tropical Pacific Ocean

Abstract

The production of sulfate aerosols through marine sulfur chemistry is critical to the climate system. However, not all sulfur compounds have been studied in detail. One such compound is methanesulfonic acid (MSA). In this study, we use a one-dimensional chemical transport model to analyze observed vertical profiles of gas-phase MSA during the Pacific Atmospheric Sulfur Experiment (PASE). The observed sharp decrease in MSA from the surface to 600m implies a surface source of 4.0×107 molecules/cm2/s. Evidence suggests that this source is photolytically enhanced. We also find that the observed large increase of MSA from the boundary layer into the lower free troposphere (1000-2000m) results mainly from the degassing of MSA from dehydrated aerosols. We estimate a source of 1.2×107 molecules/cm2/s through this pathway. This source of soluble MSA potentially provides an important precursor for new particle formation in the free troposphere over tropics, affecting the climate system through aerosol-cloud interactions.

Authors:
; ; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1172464
Report Number(s):
PNNL-SA-104715
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Geophysical Research Letters, 41(14):5239-5245
Country of Publication:
United States
Language:
English

Citation Formats

Zhang, Yuzhong, Wang, Yuhang, Gray, Burton A., Gu, Dasa, Mauldin, L., Cantrell, Chris, and Bandy, Alan R.. Surface and free tropospheric sources of methanesulfonic acid over the tropical Pacific Ocean. United States: N. p., 2014. Web. doi:10.1002/2014GL060934.
Zhang, Yuzhong, Wang, Yuhang, Gray, Burton A., Gu, Dasa, Mauldin, L., Cantrell, Chris, & Bandy, Alan R.. Surface and free tropospheric sources of methanesulfonic acid over the tropical Pacific Ocean. United States. doi:10.1002/2014GL060934.
Zhang, Yuzhong, Wang, Yuhang, Gray, Burton A., Gu, Dasa, Mauldin, L., Cantrell, Chris, and Bandy, Alan R.. Mon . "Surface and free tropospheric sources of methanesulfonic acid over the tropical Pacific Ocean". United States. doi:10.1002/2014GL060934.
@article{osti_1172464,
title = {Surface and free tropospheric sources of methanesulfonic acid over the tropical Pacific Ocean},
author = {Zhang, Yuzhong and Wang, Yuhang and Gray, Burton A. and Gu, Dasa and Mauldin, L. and Cantrell, Chris and Bandy, Alan R.},
abstractNote = {The production of sulfate aerosols through marine sulfur chemistry is critical to the climate system. However, not all sulfur compounds have been studied in detail. One such compound is methanesulfonic acid (MSA). In this study, we use a one-dimensional chemical transport model to analyze observed vertical profiles of gas-phase MSA during the Pacific Atmospheric Sulfur Experiment (PASE). The observed sharp decrease in MSA from the surface to 600m implies a surface source of 4.0×107 molecules/cm2/s. Evidence suggests that this source is photolytically enhanced. We also find that the observed large increase of MSA from the boundary layer into the lower free troposphere (1000-2000m) results mainly from the degassing of MSA from dehydrated aerosols. We estimate a source of 1.2×107 molecules/cm2/s through this pathway. This source of soluble MSA potentially provides an important precursor for new particle formation in the free troposphere over tropics, affecting the climate system through aerosol-cloud interactions.},
doi = {10.1002/2014GL060934},
journal = {Geophysical Research Letters, 41(14):5239-5245},
number = ,
volume = ,
place = {United States},
year = {Mon Jul 28 00:00:00 EDT 2014},
month = {Mon Jul 28 00:00:00 EDT 2014}
}
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