Seasonal updraft speeds change cloud droplet number concentrations in low-level clouds over the western North Atlantic

S. Kirschler; C. Voigt; B. Anderson; R. Campos Braga; G. Chen; A. F. Corral; E. Crosbie; H. Dadashazar; R. A. Ferrare; V. Hahn; J. Hendricks; S. Kaufmann; R. Moore; M. L. Pöhlker; C. Robinson; A. J. Scarino; D. Schollmayer; M. A. Shook; K. L. Thornhill; E. Winstead; L. D. Ziemba; A. Sorooshian

doi:10.5194/acp-22-8299-2022

Back

Seasonal updraft speeds change cloud droplet number concentrations in low-level clouds over the western North Atlantic

Journal article

Open access

Peer reviewed

Seasonal updraft speeds change cloud droplet number concentrations in low-level clouds over the western North Atlantic

S. Kirschler, C. Voigt, B. Anderson, R. Campos Braga, G. Chen, A. F. Corral, E. Crosbie, H. Dadashazar, R. A. Ferrare, V. Hahn, …

Atmospheric chemistry and physics, Vol.22, pp.8299-8319

28/06/2022

DOI: https://doi.org/10.5194/acp-22-8299-2022

Appears in Recent Faculty of Science and Engineering Publications

Files and links (2)

pdf

Seasonal updraft speeds change cloud droplet number concentrations in low-level clouds over the western North Atlantic3.12 MBDownload View

Published (Version of record)CC BY V4.0, Open Access

url

Seasonal updraft speeds change cloud droplet number concentrations in low-level clouds over the western North AtlanticView

Published (Version of record)CC BY V4.0, Open

Metrics

43 File views/ downloads

18 Record Views

9 Times Cited - Web of Science

See more details

UN Sustainable Development Goals (SDGs)

This output has contributed to the advancement of the following goals:

Source: InCites

Abstract

Science and Technology

Environment

To determine the impact of dynamic and aerosol processes on marine low clouds, we examine the seasonal impact of updraft speed w and cloud condensation nuclei concentration at 0.43 % supersaturation (NCCN0.43 % ) on the cloud droplet number concentration (NC) of low-level clouds over the western North Atlantic Ocean. Aerosol and cloud properties were measured with instruments on board the NASA LaRC Falcon HU-25 during the ACTIVATE (Aerosol Cloud meTeorology Interactions oVer the western ATlantic Experiment) mission in summer (August) and winter (February–March) 2020. The data are grouped into different NCCN0.43 % loadings, and the density functions of NC and w near the cloud bases are compared. For low updrafts (w < 1.3 m s−1), NC in winter is mainly limited by the updraft speed and in summer additionally by aerosols. At larger updrafts (w > 3 m s−1), NC is impacted by the aerosol population, while at clean marine conditions cloud nucleation is aerosol-limited, and for high NCCN0.43 % it is influenced by aerosols and updraft. The aerosol size distribution in winter shows a bimodal distribution in clean marine environments, which transforms to a unimodal distribution in high NCCN0.43 % due to chemical and physical aerosol processes, whereas unimodal distributions prevail in summer, with a significant difference in their aerosol concentration and composition. The increase of NCCN0.43 % is accompanied with an increase of organic aerosol and sulphate compounds in both seasons. We demonstrate that NC can be explained by cloud condensation nuclei activation through upwards processed air masses with varying fractions of activated aerosols. The activation highly depends on w and thus supersaturation between the different seasons, while the aerosol size distribution additionally affects NC within a season. Our results quantify the seasonal influence of w and NCCN0.43 % on NC and can be used to improve the representation of low marine clouds in models.

Details

Title: Seasonal updraft speeds change cloud droplet number concentrations in low-level clouds over the western North Atlantic
Creators: S. Kirschler - Institute of Geosciences Johannes Gutenberg University Mainz
C. Voigt - Institute of Geosciences Johannes Gutenberg University Mainz
B. Anderson - Langley Research Center
R. Campos Braga - Southern Cross University
G. Chen - Langley Research Center
A. F. Corral - Department of Chemical and Environmental Engineering, University of Arizona, Tucson, Arizona, USA
E. Crosbie - Langley Research Center
H. Dadashazar - Department of Chemical and Environmental Engineering, University of Arizona, Tucson, Arizona, USA
R. A. Ferrare - Langley Research Center
V. Hahn - Institute of Geosciences Johannes Gutenberg University Mainz
J. Hendricks - Institut für Physik der Atmosphäre, Deutsches Zentrum für Luft- und Raumfahrt (DLR), Oberpfaffenhofen, Germany
S. Kaufmann - Institute of Geosciences Johannes Gutenberg University Mainz
R. Moore - Langley Research Center
M. L. Pöhlker - Faculty
C. Robinson - Langley Research Center
A. J. Scarino - Langley Research Center
D. Schollmayer - Institute of Geosciences Johannes Gutenberg University Mainz
M. A. Shook - Langley Research Center
K. L. Thornhill - Langley Research Center
E. Winstead - Langley Research Center
L. D. Ziemba - Langley Research Center
A. Sorooshian - Department of Chemical and Environmental Engineering, University of Arizona, Tucson, Arizona, USA
Publication Details: Atmospheric chemistry and physics, Vol.22, pp.8299-8319
Publisher: Copernicus Publications
Grant note: This research has been supported by the Earth Sciences Division (grant no. 80NSSC19K0442), the Helmholtz-Gemeinschaft (grant no. W2/W3-060) and the Deutsche Forschungsgemeinschaft (grant nos. TRR 301 – Project-ID 428312742 and SPP 1294 HALO – VO 1504/7-1). The article processing charges for this open-access publication were covered by the German Aerospace Center (DLR).
Identifiers: 991013036351302368
Academic Unit: Faculty of Science and Engineering
Language: English
Resource Type: Journal article

Seasonal updraft speeds change cloud droplet number concentrations in low-level clouds over the western North Atlantic

Files and links (2)

Metrics

UN Sustainable Development Goals (SDGs)

Abstract

Details

Southern Cross University Social media