21 Mar 2022
21 Mar 2022
Status: this preprint is currently under review for the journal ACP.

A decadal assessment of the climatology of aerosol and cloud properties over South Africa

Abdulaziz Tunde Yakubu and Naven Chetty Abdulaziz Tunde Yakubu and Naven Chetty
  • Discipline of Physics, School of Chemistry and Physics, University of KwaZulu-Natal, Pietermaritzburg, 3209, South Africa

Abstract. Aerosol-cloud interaction (ACI) plays an essential role in understanding precipitation occurrence and climate change but remains poorly understood. Conducting a climatology study on a regional or global scale constitutes a prospect better to understand ACI and its influence on precipitation and climate. This study analysed the characteristics of ACI over South Africa based on two instruments Moderate Resolution Imaging Spectroradiometer (MODIS) and Multiangle Imaging Spectroradiometer (MISR) onboard Terra satellite, and ground-based meteorology data from South Africa Weather Service (SAWS) between 2007–2016. The region mainly splits into the upper, central, and lower sub-regions based on the aerosol loading characteristics. Findings from the study show that depending on the atmospheric conditions, aerosol exhibits dual features of increasing and decreasing the potential formation of precipitating clouds. However, more often, fine-mode predominated aerosols suppress rain-bearing clouds. Furthermore, cloud top height (CTH) demonstrates upward increment from the lower to the upper part of the region, and the cloud fraction (CF) is in the downward direction. Both the CF and CTH display the characteristic enhancers of the precipitation intensity, mainly when the initial conditions necessary for rain-bearing occurs. Besides, cloud optical depth (COD) depends significantly on the liquid water path (LWP) and is suggestively associated with the aerosol-vapour ratio ingested into the cloud. Also notably, the temperature over the entire region generally increased steadily and continuously from 2013.

Abdulaziz Tunde Yakubu and Naven Chetty

Status: open (extended)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on acp-2021-796', Anonymous Referee #3, 02 May 2022 reply

Abdulaziz Tunde Yakubu and Naven Chetty

Abdulaziz Tunde Yakubu and Naven Chetty


Total article views: 262 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
207 47 8 262 2 2
  • HTML: 207
  • PDF: 47
  • XML: 8
  • Total: 262
  • BibTeX: 2
  • EndNote: 2
Views and downloads (calculated since 21 Mar 2022)
Cumulative views and downloads (calculated since 21 Mar 2022)

Viewed (geographical distribution)

Total article views: 231 (including HTML, PDF, and XML) Thereof 231 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
Latest update: 27 May 2022
Short summary
This study examined the source of atmospheric aerosols and their role in forming clouds and rainfall over South Africa. The research provided answers to the cause of low precipitation, mainly linked to drought and water shortages experienced over the region. Further insight into the cause of occasional flooding that occurs in other parts of the area is provided. Finally, the study described the relationship between aerosol-cloud-precipitation based on observation over the region.