Insights into the Optical and Physical Characteristics of Low Clouds and Aerosols in Africa from Satellite Lidar Measurements
This study presents a systematic analysis of the optical-physical properties of low clouds and their vertical interaction mechanisms with aerosols over three African sub-regions (A: North African Desert; B: Congo Basin; C: Southeastern Plateau and Coastal Zone) using CALIPSO satellite vertical obser...
Saved in:
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2025-06-01
|
| Series: | Atmosphere |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2073-4433/16/6/717 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1849435218655576064 |
|---|---|
| author | Bo Su Dekai Lin Xiaozhe Lv Shuo Kong Wenkai Song Miao Zhang |
| author_facet | Bo Su Dekai Lin Xiaozhe Lv Shuo Kong Wenkai Song Miao Zhang |
| author_sort | Bo Su |
| collection | DOAJ |
| description | This study presents a systematic analysis of the optical-physical properties of low clouds and their vertical interaction mechanisms with aerosols over three African sub-regions (A: North African Desert; B: Congo Basin; C: Southeastern Plateau and Coastal Zone) using CALIPSO satellite vertical observations taken between 2006 and 2021. The results revealed distinct spatiotemporal variations: For example, the low-cloud aerosol optical depth (AOD) in Region A peaked during December–February, while Regions B and C exhibited higher values from June to November, with elevated dry-season and daytime levels. A positive correlation emerged between low-cloud AOD and its fractional contribution. Regional contrasts in low-cloud vertical structure were evident, with Region C showing the highest seasonal mean cloud base/top heights and Region A the lowest. The depolarisation ratio of low clouds was higher in desert areas (Region A) but lower in rainforest regions (Region B), while the SRlc (Low-cloud spectral reflectance ratio) was maximised in the Congo Basin (Region B), with wet-season and daytime enhancements. The near-surface aerosol AOD in Regions A and B was positively correlated with low-cloud AOD proportion (PAOD<sub>lc</sub>). Across all regions, the near-surface aerosol layer top height showed positive correlations with the low-cloud base height and vertical extent, while the height of the bottom of the near-surface aerosol layer was positively aligned with the low-cloud base height. For Region C, there were negative correlations between near-surface aerosol layer heights and PAOD<sub>lc</sub>, whereas the springtime aerosol parameters in Region A exhibited positive PAOD<sub>lc</sub> correlations. These findings advance the current understanding of aerosol sources and ecosystem impacts, and provide critical insights for refining aerosol and low-cloud parameterisations in climate models. |
| format | Article |
| id | doaj-art-e345e14dc61e4d18bd614f94d2135e8d |
| institution | Kabale University |
| issn | 2073-4433 |
| language | English |
| publishDate | 2025-06-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Atmosphere |
| spelling | doaj-art-e345e14dc61e4d18bd614f94d2135e8d2025-08-20T03:26:21ZengMDPI AGAtmosphere2073-44332025-06-0116671710.3390/atmos16060717Insights into the Optical and Physical Characteristics of Low Clouds and Aerosols in Africa from Satellite Lidar MeasurementsBo Su0Dekai Lin1Xiaozhe Lv2Shuo Kong3Wenkai Song4Miao Zhang5Academy of Remote Sensing Technology and Application, Nanyang Normal University, Wolong Road No. 1638, Nanyang 473061, ChinaAcademy of Remote Sensing Technology and Application, Nanyang Normal University, Wolong Road No. 1638, Nanyang 473061, ChinaAcademy of Remote Sensing Technology and Application, Nanyang Normal University, Wolong Road No. 1638, Nanyang 473061, ChinaAcademy of Remote Sensing Technology and Application, Nanyang Normal University, Wolong Road No. 1638, Nanyang 473061, ChinaAcademy of Remote Sensing Technology and Application, Nanyang Normal University, Wolong Road No. 1638, Nanyang 473061, ChinaAcademy of Remote Sensing Technology and Application, Nanyang Normal University, Wolong Road No. 1638, Nanyang 473061, ChinaThis study presents a systematic analysis of the optical-physical properties of low clouds and their vertical interaction mechanisms with aerosols over three African sub-regions (A: North African Desert; B: Congo Basin; C: Southeastern Plateau and Coastal Zone) using CALIPSO satellite vertical observations taken between 2006 and 2021. The results revealed distinct spatiotemporal variations: For example, the low-cloud aerosol optical depth (AOD) in Region A peaked during December–February, while Regions B and C exhibited higher values from June to November, with elevated dry-season and daytime levels. A positive correlation emerged between low-cloud AOD and its fractional contribution. Regional contrasts in low-cloud vertical structure were evident, with Region C showing the highest seasonal mean cloud base/top heights and Region A the lowest. The depolarisation ratio of low clouds was higher in desert areas (Region A) but lower in rainforest regions (Region B), while the SRlc (Low-cloud spectral reflectance ratio) was maximised in the Congo Basin (Region B), with wet-season and daytime enhancements. The near-surface aerosol AOD in Regions A and B was positively correlated with low-cloud AOD proportion (PAOD<sub>lc</sub>). Across all regions, the near-surface aerosol layer top height showed positive correlations with the low-cloud base height and vertical extent, while the height of the bottom of the near-surface aerosol layer was positively aligned with the low-cloud base height. For Region C, there were negative correlations between near-surface aerosol layer heights and PAOD<sub>lc</sub>, whereas the springtime aerosol parameters in Region A exhibited positive PAOD<sub>lc</sub> correlations. These findings advance the current understanding of aerosol sources and ecosystem impacts, and provide critical insights for refining aerosol and low-cloud parameterisations in climate models.https://www.mdpi.com/2073-4433/16/6/717low cloudsaerosoloptical propertyvertical distributionCALIPSO satellite |
| spellingShingle | Bo Su Dekai Lin Xiaozhe Lv Shuo Kong Wenkai Song Miao Zhang Insights into the Optical and Physical Characteristics of Low Clouds and Aerosols in Africa from Satellite Lidar Measurements Atmosphere low clouds aerosol optical property vertical distribution CALIPSO satellite |
| title | Insights into the Optical and Physical Characteristics of Low Clouds and Aerosols in Africa from Satellite Lidar Measurements |
| title_full | Insights into the Optical and Physical Characteristics of Low Clouds and Aerosols in Africa from Satellite Lidar Measurements |
| title_fullStr | Insights into the Optical and Physical Characteristics of Low Clouds and Aerosols in Africa from Satellite Lidar Measurements |
| title_full_unstemmed | Insights into the Optical and Physical Characteristics of Low Clouds and Aerosols in Africa from Satellite Lidar Measurements |
| title_short | Insights into the Optical and Physical Characteristics of Low Clouds and Aerosols in Africa from Satellite Lidar Measurements |
| title_sort | insights into the optical and physical characteristics of low clouds and aerosols in africa from satellite lidar measurements |
| topic | low clouds aerosol optical property vertical distribution CALIPSO satellite |
| url | https://www.mdpi.com/2073-4433/16/6/717 |
| work_keys_str_mv | AT bosu insightsintotheopticalandphysicalcharacteristicsoflowcloudsandaerosolsinafricafromsatellitelidarmeasurements AT dekailin insightsintotheopticalandphysicalcharacteristicsoflowcloudsandaerosolsinafricafromsatellitelidarmeasurements AT xiaozhelv insightsintotheopticalandphysicalcharacteristicsoflowcloudsandaerosolsinafricafromsatellitelidarmeasurements AT shuokong insightsintotheopticalandphysicalcharacteristicsoflowcloudsandaerosolsinafricafromsatellitelidarmeasurements AT wenkaisong insightsintotheopticalandphysicalcharacteristicsoflowcloudsandaerosolsinafricafromsatellitelidarmeasurements AT miaozhang insightsintotheopticalandphysicalcharacteristicsoflowcloudsandaerosolsinafricafromsatellitelidarmeasurements |