Composition and mixing state of Arctic aerosol and cloud residual particles from long-term single-particle observations at Zeppelin Observatory, Svalbard
<p>The Arctic region is sensitive to climate change and is warming faster than the global average. Aerosol particles change cloud properties by acting as cloud condensation nuclei and ice-nucleating particles, thus influencing the Arctic climate system. Therefore, understanding the aerosol par...
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2022-11-01
|
| Series: | Atmospheric Chemistry and Physics |
| Online Access: | https://acp.copernicus.org/articles/22/14421/2022/acp-22-14421-2022.pdf |
| Summary: | <p>The Arctic region is sensitive to climate change and is
warming faster than the global average. Aerosol particles change cloud
properties by acting as cloud condensation nuclei and ice-nucleating
particles, thus influencing the Arctic climate system. Therefore,
understanding the aerosol particle properties in the Arctic is needed to
interpret and simulate their influences on climate. In this study, we
collected ambient aerosol particles using whole-air and PM<span class="inline-formula"><sub>10</sub></span> inlets and
residual particles of cloud droplets and ice crystals from Arctic low-level
clouds (typically, all-liquid or mixed-phase clouds) using a counterflow
virtual impactor inlet at the Zeppelin Observatory near Ny-Ålesund,
Svalbard, within a time frame of 4 years. We measured the composition and
mixing state of individual fine-mode particles in 239 samples using
transmission electron microscopy. On the basis of their composition, the
aerosol and cloud residual particles were classified as mineral dust, sea
salt, K-bearing, sulfate, and carbonaceous particles. The number fraction of
aerosol particles showed seasonal changes, with sulfate dominating in summer
and sea salt increasing in winter. There was no measurable difference in the
fractions between ambient aerosol and cloud residual particles collected at
ambient temperatures above 0 <span class="inline-formula"><sup>∘</sup></span>C. On the other hand, cloud residual
samples collected at ambient temperatures below 0 <span class="inline-formula"><sup>∘</sup></span>C had several
times more sea salt and mineral dust particles and fewer sulfates than
ambient aerosol samples, suggesting that sea spray and mineral dust
particles may influence the formation of cloud particles in Arctic
mixed-phase clouds. We also found that 43 % of mineral dust particles from
cloud residual samples were mixed with sea salt, whereas only 18 % of
mineral dust particles in ambient aerosol samples were mixed with sea salt.
This study highlights the variety in aerosol compositions and mixing states
that influence or are influenced by aerosol–cloud interactions in Arctic
low-level clouds.</p> |
|---|---|
| ISSN: | 1680-7316 1680-7324 |