Preprints
https://doi.org/10.5194/egusphere-2022-1023
https://doi.org/10.5194/egusphere-2022-1023
09 Nov 2022
 | 09 Nov 2022

Further validation of the McClear estimates of the downwelling solar radiation at ground level in cloud-free conditions: The case of the Sub-Saharan Africa and Maldives Archipelago

William Wandji Nyamsi, Yves-Marie Saint-Drenan, Antti Arola, and Lucien Wald

Abstract. Being itself part of the Copernicus Atmosphere Monitoring Service (CAMS), the McClear service provides estimates of the downwelling shortwave irradiance and its direct and diffuse components received at ground level in cloud-free conditions, with inputs on ozone, water vapor and aerosol properties from CAMS. McClear estimates have been validated over several parts of the world by various authors. This article makes a step forward by comparing McClear estimates to measurements performed at 44 ground-based stations located in the Sub-Saharan Africa and Maldives Archipelago in the Indian Ocean. The global irradiances G and its direct component at normal incidence BN from McClear-v3 were compared to 1 min measurements made in cloud-free conditions at the stations. The correlation coefficient is greater than 0.96 for G whereas it is greater than 0.70 at all stations but five for BN. The mean of G is correctly estimated at stations located in arid climates (BSh, BWh, BSk, BWk) and temperate climates without dry season and hot or warm summer (Cfa, Cfb) or with dry and hot summer (Csa) with a relative bias in the range [−1.5, 1.5] %. It is underestimated in tropical climate of monsoon type (Am) and overestimated in tropical climate of savannah type (Aw) and temperate climates with dry winter and hot (Cwa) or warm (Cwb) summer. McClear tends to overestimate the means of BN. The standard deviation of errors for G ranges between 13 W m−2 (1.3 %) and 31 W m−2 (3.7 %) and that for BN ranges between 31 W m−2 (3.0 %) and 70 W m−2 (7.9 %). Both offer small variations in time and space. A review of previous works reveals no significant difference between their results and ours. This work establishes a general overview of the performances of the McClear service.

Publisher's note: Copernicus Publications remains neutral with regard to jurisdictional claims made in the text, published maps, institutional affiliations, or any other geographical representation in this preprint. The responsibility to include appropriate place names lies with the authors.

Journal article(s) based on this preprint

17 Apr 2023
Further validation of the estimates of the downwelling solar radiation at ground level in cloud-free conditions provided by the McClear service: the case of Sub-Saharan Africa and the Maldives Archipelago
William Wandji Nyamsi, Yves-Marie Saint-Drenan, Antti Arola, and Lucien Wald
Atmos. Meas. Tech., 16, 2001–2036, https://doi.org/10.5194/amt-16-2001-2023,https://doi.org/10.5194/amt-16-2001-2023, 2023
Short summary
William Wandji Nyamsi, Yves-Marie Saint-Drenan, Antti Arola, and Lucien Wald

Interactive discussion

Status: closed

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on egusphere-2022-1023', Brighton Mabasa, 01 Dec 2022
    • AC1: 'Reply on RC1', William Wandji, 21 Feb 2023
  • RC2: 'Comment on egusphere-2022-1023', Anonymous Referee #2, 24 Jan 2023
    • AC2: 'Reply on RC2', William Wandji, 21 Feb 2023

Interactive discussion

Status: closed

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on egusphere-2022-1023', Brighton Mabasa, 01 Dec 2022
    • AC1: 'Reply on RC1', William Wandji, 21 Feb 2023
  • RC2: 'Comment on egusphere-2022-1023', Anonymous Referee #2, 24 Jan 2023
    • AC2: 'Reply on RC2', William Wandji, 21 Feb 2023

Peer review completion

AR: Author's response | RR: Referee report | ED: Editor decision | EF: Editorial file upload
AR by William Wandji on behalf of the Authors (21 Feb 2023)  Author's response   Author's tracked changes   Manuscript 
ED: Referee Nomination & Report Request started (23 Feb 2023) by Udo Friess
RR by Anonymous Referee #2 (13 Mar 2023)
ED: Publish as is (14 Mar 2023) by Udo Friess
AR by William Wandji on behalf of the Authors (18 Mar 2023)

Journal article(s) based on this preprint

17 Apr 2023
Further validation of the estimates of the downwelling solar radiation at ground level in cloud-free conditions provided by the McClear service: the case of Sub-Saharan Africa and the Maldives Archipelago
William Wandji Nyamsi, Yves-Marie Saint-Drenan, Antti Arola, and Lucien Wald
Atmos. Meas. Tech., 16, 2001–2036, https://doi.org/10.5194/amt-16-2001-2023,https://doi.org/10.5194/amt-16-2001-2023, 2023
Short summary
William Wandji Nyamsi, Yves-Marie Saint-Drenan, Antti Arola, and Lucien Wald
William Wandji Nyamsi, Yves-Marie Saint-Drenan, Antti Arola, and Lucien Wald

Viewed

Total article views: 457 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
340 103 14 457 46 6 5
  • HTML: 340
  • PDF: 103
  • XML: 14
  • Total: 457
  • Supplement: 46
  • BibTeX: 6
  • EndNote: 5
Views and downloads (calculated since 09 Nov 2022)
Cumulative views and downloads (calculated since 09 Nov 2022)

Viewed (geographical distribution)

Total article views: 447 (including HTML, PDF, and XML) Thereof 447 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 31 Aug 2024
Download

The requested preprint has a corresponding peer-reviewed final revised paper. You are encouraged to refer to the final revised version.

Short summary
The McClear service provides estimates of the surface solar irradiances in cloud-free conditions. By comparing McClear estimates to 1 min measurements performed in the Sub-Saharan Africa and Maldives Archipelago in the Indian Ocean, McClear estimates correctly global and tends to overestimate direct irrradiances. A review of previous works reveals no significant difference between their results and ours. This work establishes a general overview of the performances of the McClear service.