Aerosol–Cloud Interaction at the Summit of Mt. Fuji, Japan: Factors Influencing Cloud Droplet Number Concentrations
To investigate interactions between aerosols and clouds, the size and number concentrations of the cloud condensation nuclei (CCN) and the cloud droplets (CDs) were measured at the summit of Mt. Fuji (altitude 3776 m), Japan. The CCN number concentrations (<i>N</i><sub>CCN</sub&...
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-09-01
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| Series: | Applied Sciences |
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| Online Access: | https://www.mdpi.com/2076-3417/11/18/8439 |
| _version_ | 1797520372402225152 |
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| author | Yoko Iwamoto Ayami Watanabe Ryota Kataoka Mitsuo Uematsu Kazuhiko Miura |
| author_facet | Yoko Iwamoto Ayami Watanabe Ryota Kataoka Mitsuo Uematsu Kazuhiko Miura |
| author_sort | Yoko Iwamoto |
| collection | DOAJ |
| description | To investigate interactions between aerosols and clouds, the size and number concentrations of the cloud condensation nuclei (CCN) and the cloud droplets (CDs) were measured at the summit of Mt. Fuji (altitude 3776 m), Japan. The CCN number concentrations (<i>N</i><sub>CCN</sub>) are significantly higher in continental air masses than in air masses from the Pacific Ocean. The hygroscopicity parameter <i>κ</i> did not change much for different air mass origins, indicating that aerosol particles in the free troposphere are well mixed. Based on the CD number concentrations (<i>N</i><sub>CD</sub>), the degree of supersaturation in the ambient air during the cloud-shrouded period was estimated to be 0.15% (25th percentile) to 0.44% (75th percentile). To evaluate factors influencing the <i>N</i><sub>CD</sub>, measured <i>N</i><sub>CD</sub> were compared to ones calculated based on the Köhler theory using aerosol number size distributions, <i>κ</i>, and the degree of supersaturation. The results showed that <i>N</i><sub>CD</sub> could not be reproduced satisfyingly when the mean number size distribution or the mean effective supersaturation were used for the calculation. This study highlights the importance of obtaining information about the degree of supersaturation to predict <i>N</i><sub>CD</sub> in the atmosphere. |
| first_indexed | 2024-03-10T07:55:50Z |
| format | Article |
| id | doaj.art-2239a3d552344ceeb4f67a3d7d483c84 |
| institution | Directory Open Access Journal |
| issn | 2076-3417 |
| language | English |
| last_indexed | 2024-03-10T07:55:50Z |
| publishDate | 2021-09-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Applied Sciences |
| spelling | doaj.art-2239a3d552344ceeb4f67a3d7d483c842023-11-22T11:52:44ZengMDPI AGApplied Sciences2076-34172021-09-011118843910.3390/app11188439Aerosol–Cloud Interaction at the Summit of Mt. Fuji, Japan: Factors Influencing Cloud Droplet Number ConcentrationsYoko Iwamoto0Ayami Watanabe1Ryota Kataoka2Mitsuo Uematsu3Kazuhiko Miura4Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima 739-8521, JapanGraduate School of Science, Tokyo University of Science, Tokyo 162-8601, JapanGraduate School of Science, Tokyo University of Science, Tokyo 162-8601, JapanAtmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa 277-8564, JapanFaculty of Science Division I, Tokyo University of Science, Tokyo 162-8601, JapanTo investigate interactions between aerosols and clouds, the size and number concentrations of the cloud condensation nuclei (CCN) and the cloud droplets (CDs) were measured at the summit of Mt. Fuji (altitude 3776 m), Japan. The CCN number concentrations (<i>N</i><sub>CCN</sub>) are significantly higher in continental air masses than in air masses from the Pacific Ocean. The hygroscopicity parameter <i>κ</i> did not change much for different air mass origins, indicating that aerosol particles in the free troposphere are well mixed. Based on the CD number concentrations (<i>N</i><sub>CD</sub>), the degree of supersaturation in the ambient air during the cloud-shrouded period was estimated to be 0.15% (25th percentile) to 0.44% (75th percentile). To evaluate factors influencing the <i>N</i><sub>CD</sub>, measured <i>N</i><sub>CD</sub> were compared to ones calculated based on the Köhler theory using aerosol number size distributions, <i>κ</i>, and the degree of supersaturation. The results showed that <i>N</i><sub>CD</sub> could not be reproduced satisfyingly when the mean number size distribution or the mean effective supersaturation were used for the calculation. This study highlights the importance of obtaining information about the degree of supersaturation to predict <i>N</i><sub>CD</sub> in the atmosphere.https://www.mdpi.com/2076-3417/11/18/8439cloud condensation nucleihigh alpine sitesize distributionhygroscopicity parameterwater vapor supersaturation |
| spellingShingle | Yoko Iwamoto Ayami Watanabe Ryota Kataoka Mitsuo Uematsu Kazuhiko Miura Aerosol–Cloud Interaction at the Summit of Mt. Fuji, Japan: Factors Influencing Cloud Droplet Number Concentrations Applied Sciences cloud condensation nuclei high alpine site size distribution hygroscopicity parameter water vapor supersaturation |
| title | Aerosol–Cloud Interaction at the Summit of Mt. Fuji, Japan: Factors Influencing Cloud Droplet Number Concentrations |
| title_full | Aerosol–Cloud Interaction at the Summit of Mt. Fuji, Japan: Factors Influencing Cloud Droplet Number Concentrations |
| title_fullStr | Aerosol–Cloud Interaction at the Summit of Mt. Fuji, Japan: Factors Influencing Cloud Droplet Number Concentrations |
| title_full_unstemmed | Aerosol–Cloud Interaction at the Summit of Mt. Fuji, Japan: Factors Influencing Cloud Droplet Number Concentrations |
| title_short | Aerosol–Cloud Interaction at the Summit of Mt. Fuji, Japan: Factors Influencing Cloud Droplet Number Concentrations |
| title_sort | aerosol cloud interaction at the summit of mt fuji japan factors influencing cloud droplet number concentrations |
| topic | cloud condensation nuclei high alpine site size distribution hygroscopicity parameter water vapor supersaturation |
| url | https://www.mdpi.com/2076-3417/11/18/8439 |
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