Seasonal cycles and long-term trends of arctic tropospheric aerosols based on CALIPSO lidar observations

Wenrui Yao; Ke Gui; Yu Zheng; Lei Li; Yaqiang Wang; Huizheng Che; Xiaoye Zhang

doi:10.1016/j.envres.2022.114613

Seasonal cycles and long-term trends of arctic tropospheric aerosols based on CALIPSO lidar observations

Environ Res. 2023 Jan 1;216(Pt 2):114613. doi: 10.1016/j.envres.2022.114613. Epub 2022 Oct 20.

Authors

Wenrui Yao¹, Ke Gui², Yu Zheng³, Lei Li³, Yaqiang Wang³, Huizheng Che⁴, Xiaoye Zhang³

Affiliations

¹ State Key Laboratory of Severe Weather & Key Laboratory of Atmospheric Chemistry of CMA, Chinese Academy of Meteorological Sciences, Beijing, 100081, China; Department of Atmospheric and Oceanic Sciences & Institute of Atmospheric Sciences, Fudan University, Shanghai, 200438, China.
² State Key Laboratory of Severe Weather & Key Laboratory of Atmospheric Chemistry of CMA, Chinese Academy of Meteorological Sciences, Beijing, 100081, China. Electronic address: guik@cma.gov.cn.
³ State Key Laboratory of Severe Weather & Key Laboratory of Atmospheric Chemistry of CMA, Chinese Academy of Meteorological Sciences, Beijing, 100081, China.
⁴ State Key Laboratory of Severe Weather & Key Laboratory of Atmospheric Chemistry of CMA, Chinese Academy of Meteorological Sciences, Beijing, 100081, China. Electronic address: chehz@cma.gov.cn.

PMID: 36272597
DOI: 10.1016/j.envres.2022.114613

Abstract

Notable warming trends have been observed in the Arctic, with tropospheric aerosols being one of the key drivers. Here the seasonal cycles of three-dimensional (3D) distributions of aerosol extinction coefficients (AECs) and frequency of occurrences (FoOs) for different aerosol subtypes in the troposphere over the Arctic from 2007 to 2019 are characterized capitalizing on Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) Level-3 gridded aerosol profile product. Seasonal contributions of total and type-dependent aerosols through their partitioning within the planetary boundary layer (PBL) and free troposphere (FT) are also quantified utilizing the Modern-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2) PBL height data. The results show substantial seasonal and geographical dependence in the distribution of aerosols over the Arctic. Sulfate, black carbon (BC), and organic carbon (OC) contribute most of the total AEC, with Eurasia being the largest contributor. The vertical structure of AECs and FoOs over the Arctic demonstrates that the vertical influence of aerosols is higher in eastern Siberia and North America than in northern Eurasia and its coasts. When the total aerosol optical depth (TAOD) is partitioned into the PBL and FT, results indicate that the contributions of TAOD within the FT tend to be more significant, especially in summer, with the FT contributes 64.2% and 69.2% of TAOD over the lower (i.e., 60° N-70° N) and high (i.e., north of 70° N) Arctic, respectively. Additionally, seasonal trend analyses suggest Arctic TAOD exhibits a multi-year negative trend in winter, spring, and autumn and a positive trend in summer during 2007-2019, due to an overall decrease in sulfate from weakened anthropogenic emissions and a significant increase in BC and OC from enhanced biomass burning activities. Overall, this study has potential implications for understanding the seasonal cycles and trends in Arctic aerosols.

Keywords: Arctic; CALIPSO; Frequency of occurrence; Tropospheric aerosols; Vertical distribution.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Aerosols / analysis
Air Pollutants* / analysis
Carbon
Environmental Monitoring / methods
Retrospective Studies
Seasons
Soot / analysis
Sulfates

Substances

Air Pollutants
Aerosols
Soot
Carbon
Sulfates