Aerosol indirect effects on continental low-level clouds over Sweden and Finland
Sporre, Moa LU
; Swietlicki, Erik
LU
; Glantz, P.
and Kulmala, M.
(2014)
In Atmospheric Chemistry and Physics
14(22).
p.12167-12179
- Abstract
- Aerosol effects on low-level clouds over the Nordic Countries are investigated by combining in situ ground-based aerosol measurements with remote sensing data of clouds and precipitation. Ten years of number size distribution data from two aerosol measurement stations (Vavihill, Sweden and Hyytiälä, Finland) provide aerosol number concentrations in the atmospheric boundary layer. This is combined with cloud satellite data from the Moderate Resolution Imaging Spectroradiometer and weather radar data from the Baltic Sea Experiment. Also, how the meteorological conditions affect the clouds is investigated using reanalysis data from the European Centre for Medium-Range Weather Forecasts.
The cloud droplet effective radius... (More) - Aerosol effects on low-level clouds over the Nordic Countries are investigated by combining in situ ground-based aerosol measurements with remote sensing data of clouds and precipitation. Ten years of number size distribution data from two aerosol measurement stations (Vavihill, Sweden and Hyytiälä, Finland) provide aerosol number concentrations in the atmospheric boundary layer. This is combined with cloud satellite data from the Moderate Resolution Imaging Spectroradiometer and weather radar data from the Baltic Sea Experiment. Also, how the meteorological conditions affect the clouds is investigated using reanalysis data from the European Centre for Medium-Range Weather Forecasts.
The cloud droplet effective radius is found to decrease when the aerosol number concentration increases, while the cloud optical thickness does not vary with boundary layer aerosol number concentrations. Furthermore, the aerosol–cloud interaction parameter (ACI), a measure of how the effective radius is influenced by the number concentration of cloud active particles, is found to be somewhere between 0.10 and 0.18 and the magnitude of the ACI is greatest when the number concentration of particles with a diameter larger than 130 nm is used. Lower precipitation intensity in the weather radar images is associated with higher aerosol number concentrations. In addition, at Hyytiälä the particle number concentrations is generally higher for non-precipitating cases than for precipitating cases. The apparent absence of the first indirect effect of aerosols on low-level clouds over land raises questions regarding the magnitude of the indirect aerosol radiative forcing. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/4857371
- author
- Sporre, Moa
LU
; Swietlicki, Erik
LU
; Glantz, P.
and Kulmala, M.
- organization
- publishing date
- 2014
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Atmospheric Chemistry and Physics
- volume
- 14
- issue
- 22
- pages
- 12167 - 12179
- publisher
- Copernicus GmbH
- external identifiers
-
- wos:000345290700011
- scopus:85007004577
- ISSN
- 1680-7324
- DOI
- 10.5194/acp-14-12167-2014
- language
- English
- LU publication?
- yes
- additional info
- The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Nuclear Physics (Faculty of Technology) (011013007)
- id
- c24f10d4-b2da-4e52-aae8-1011ac0451c7 (old id 4857371)
- alternative location
- http://www.atmos-chem-phys.net/14/12167/2014/
- date added to LUP
- 2016-04-01 10:00:40
- date last changed
- 2022-02-02 05:32:26
@article{c24f10d4-b2da-4e52-aae8-1011ac0451c7,
abstract = {{Aerosol effects on low-level clouds over the Nordic Countries are investigated by combining in situ ground-based aerosol measurements with remote sensing data of clouds and precipitation. Ten years of number size distribution data from two aerosol measurement stations (Vavihill, Sweden and Hyytiälä, Finland) provide aerosol number concentrations in the atmospheric boundary layer. This is combined with cloud satellite data from the Moderate Resolution Imaging Spectroradiometer and weather radar data from the Baltic Sea Experiment. Also, how the meteorological conditions affect the clouds is investigated using reanalysis data from the European Centre for Medium-Range Weather Forecasts. <br/><br>
<br/><br>
The cloud droplet effective radius is found to decrease when the aerosol number concentration increases, while the cloud optical thickness does not vary with boundary layer aerosol number concentrations. Furthermore, the aerosol–cloud interaction parameter (ACI), a measure of how the effective radius is influenced by the number concentration of cloud active particles, is found to be somewhere between 0.10 and 0.18 and the magnitude of the ACI is greatest when the number concentration of particles with a diameter larger than 130 nm is used. Lower precipitation intensity in the weather radar images is associated with higher aerosol number concentrations. In addition, at Hyytiälä the particle number concentrations is generally higher for non-precipitating cases than for precipitating cases. The apparent absence of the first indirect effect of aerosols on low-level clouds over land raises questions regarding the magnitude of the indirect aerosol radiative forcing.}},
author = {{Sporre, Moa and Swietlicki, Erik and Glantz, P. and Kulmala, M.}},
issn = {{1680-7324}},
language = {{eng}},
number = {{22}},
pages = {{12167--12179}},
publisher = {{Copernicus GmbH}},
series = {{Atmospheric Chemistry and Physics}},
title = {{Aerosol indirect effects on continental low-level clouds over Sweden and Finland}},
url = {{http://dx.doi.org/10.5194/acp-14-12167-2014}},
doi = {{10.5194/acp-14-12167-2014}},
volume = {{14}},
year = {{2014}},
}