Isotopic constraints on atmospheric sulfate formation pathways in the Mt. Everest region, southern Tibetan Plateau
-
Published:2021-06-01
Issue:10
Volume:21
Page:8357-8376
-
ISSN:1680-7324
-
Container-title:Atmospheric Chemistry and Physics
-
language:en
-
Short-container-title:Atmos. Chem. Phys.
Author:
Wang Kun, Hattori ShoheiORCID, Lin MangORCID, Ishino SakikoORCID, Alexander BeckyORCID, Kamezaki KazukiORCID, Yoshida NaohiroORCID, Kang Shichang
Abstract
Abstract. As an important atmosphere constituent, sulfate aerosols exert profound impacts on climate, the ecological environment, and human health. The Tibetan Plateau (TP), identified as the “Third Pole”, contains the largest land ice masses outside the poles and has attracted widespread attention for its environment and climatic change. However, the mechanisms of sulfate formation in this specific region still remain poorly characterized. An oxygen-17 anomaly (Δ17O) has been used as a probe to constrain the relative importance of different pathways leading to sulfate formation. Here, we report the Δ17O values in atmospheric sulfate collected at a remote site in the Mt. Everest region to decipher the possible formation mechanisms of sulfate in such a pristine environment. Throughout the sampling campaign (April–September 2018), the Δ17O in non-dust sulfate show an average of 1.7 ‰±0.5 ‰, which is higher than most existing data on modern atmospheric sulfate. The seasonality of Δ17O in non-dust sulfate exhibits high values in the pre-monsoon and low values in the monsoon, opposite to the seasonality in Δ17O for both sulfate and nitrate (i.e., minima in the warm season and maxima in the cold season) observed from diverse geographic sites. This high Δ17O in non-dust sulfate found in this region clearly indicates the important role of the S(IV)+O3 pathway in atmospheric sulfate formation promoted by conditions of high cloud water pH. Overall, our study provides an observational constraint on atmospheric acidity in altering sulfate formation pathways, particularly in dust-rich environments, and such identification of key processes provides an important basis for a better understanding of the sulfur cycle in the TP.
Funder
Japan Society for the Promotion of Science National Science Foundation National Natural Science Foundation of China
Publisher
Copernicus GmbH
Subject
Atmospheric Science
Reference115 articles.
1. Alexander, B., Savarino, J., Barkov, N., Delmas, R., and Thiemens, M.: Climate driven changes in the oxidation pathways of atmospheric sulfur, Geophys. Res. Lett., 29, 1685, https://doi.org/10.1029/2002GL014879, 2002. 2. Alexander, B., Park, R. J., Jacob, D. J., Li, Q., Yantosca, R. M., Savarino, J., Lee, C., and Thiemens, M.: Sulfate formation in sea-salt aerosols: Constraints from oxygen isotopes, J. Geophys. Res.-Atmos., 110, D10307, https://doi.org/10.1029/2004JD005659, 2005. 3. Alexander, B., Park, R. J., Jacob, D. J., and Gong, S.: Transition metal-catalyzed oxidation of atmospheric sulfur: Global implications for the sulfur budget, J. Geophys. Res., 114, D02309, https://doi.org/10.1029/2008JD010486, 2009. 4. Alexander, B., Allman, D., Amos, H., Fairlie, T., Dachs, J., Hegg, D. A., and Sletten, R. S.: Isotopic constraints on the formation pathways of sulfate aerosol in the marine boundary layer of the subtropical northeast Atlantic Ocean, J. Geophys. Res.-Atmos., 117, D06304, https://doi.org/10.1029/2011JD016773, 2012. 5. Banzhaf, S., Schaap, M., Kerschbaumer, A., Reimer, E., Stern, R., Van Der Swaluw, E., and Builtjes, P.: Implementation and evaluation of pH-dependent cloud chemistry and wet deposition in the chemical transport model REM-Calgrid, Atmos. Environ., 49, 378–390, https://doi.org/10.1016/j.atmosenv.2011.10.069, 2012.
Cited by
18 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献
|
|