Highly Hygroscopic Aerosols Facilitate Summer and Early‐Autumn Cloud Formation at Extremely Low Concentrations Over the Central Arctic Ocean

Author:

Duplessis P.1ORCID,Karlsson L.23,Baccarini A.45ORCID,Wheeler M.6ORCID,Leaitch W. R.7ORCID,Svenningsson B.8,Leck C.39,Schmale J.4,Zieger P.23ORCID,Chang R. Y.‐W.1ORCID

Affiliation:

1. Department of Physics and Atmospheric Science Dalhousie University Halifax NS Canada

2. Department of Environmental Science Stockholm University Stockholm Sweden

3. Bolin Centre for Climate Research Stockholm University Stockholm Sweden

4. Extreme Environments Research Laboratory École Polytechnique fédérale de Lausanne Sion Switzerland

5. Now at Laboratory for Atmospheric Processes and their Impact École Polytechnique fédérale de Lausanne Lausanne Switzerland

6. Air Quality Division Environment and Climate Change Canada Toronto ON Canada

7. Climate Research Division Environment and Climate Change Canada Toronto ON Canada

8. Department of Physics Lund University Lund Sweden

9. Department of Meteorology Stockholm University Stockholm Sweden

Abstract

AbstractArctic clouds are sensitive to atmospheric particles since these are sometimes in such low concentrations that clouds cannot always form under supersaturated water vapor conditions. This is especially true in the late summer, when aerosol concentrations are generally very low in the high Arctic. The environment changes rapidly around freeze‐up as the open waters close and snow starts accumulating on ice. We investigated droplet formation during eight significant fog events in the central Arctic Ocean, north of 80°, from August 12 to 19 September 2018 during the Arctic Ocean 2018 expedition onboard the icebreaker Oden. Calculated hygroscopicity parameters (κ) for the entire study were very high (up to κ = 0.85 ± 0.13), notably after freeze‐up, suggesting that atmospheric particles were very cloud condensation nuclei (CCN)‐active. At least one of the events showed that surface clouds were able to form and persist for at least a couple hours at aerosol concentrations less than 10 cm−3, which was previously suggested to be the minimum for cloud formation. Among these events that were considered limited in CCN, effective radii were generally larger than in the high CCN cases. In some of the fog events, droplet residuals particles did not reactivate under supersaturations up to 0.95%, suggesting either in‐droplet reactions decreased hygroscopicity, or an ambient supersaturation above 1%. These results provide insight into droplet formation during the clean late‐summer and fall of the high Arctic with limited influence from continental sources.

Funder

Ocean Frontier Institute

Knut och Alice Wallenbergs Stiftelse

Swiss Polar Institute

Ferring

Canada Research Chairs

Publisher

American Geophysical Union (AGU)

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3