Preprints
https://doi.org/10.5194/hess-2023-311
https://doi.org/10.5194/hess-2023-311
24 Jan 2024
 | 24 Jan 2024
Status: this preprint is currently under review for the journal HESS.

Assessment of Hydrology Estimates from ERA5 Reanalyses in Benin (West Africa) 

Rene Bodjrenou, Luc Ollivier Sintondji, Yekambessun M’Po N’Tcha, Diane Germain, Francis Esse Azonwade, Aymar Yaovi Bossa, Silvère Fernand Sohindji, Gilbert Hounnou, Edid Amouzouvi, and Arthur Freud Segnon Kpognin

Abstract. In West Africa, the validation of distributed models is limited by the quality and availability of point station data measured in-situ. ERA5 is a climate reanalysis produced by European Centre for Medium-range Weather Forecasts (ECMWF) and suggested to overcome this constraint. This study assessed and compared over the Benin basins at spatial and monthly time scale, the quality of ERA5 and its variant ERA5-Land (namely LAND). ERA5 relies on the single-levels version with 0.25° x 0.25° resolution while LAND is the land surface version with 0.1° x 0.1° resolution. Four variables were collected including runoff, evapotranspiration (ETR), water table depth (WTD), and soil water content (SWC). Point station data were analyzed using the correlation performance evaluators, Mean Absolute Error (m) and Relative Mean Absolute Error (r). The results showed that LAND simulates well the peaks of mean runoff. It showed the best runoff performance in terms of correlation (~0.61) compared with ERA5 (correlation ~0.49). Both reanalysis showed high correlations (generally > 0.80) for SWC, but the correlations obtained from ETR are slightly lower (ERA5~0.58 vs. ERA5-Land~0.54). Correlations were below 0.5 on both reanalyses for WTD with slight overestimation (m=4.73 m for ERA5 vs. m=3.13 m for LAND). This study does not identify any reanalysis that is better than another, both spatially and monthly scale. Nevertheless, this study indicated that the choice of reanalyses must rely on their performance and the given water cycle element. Correcting the variables of these reanalysis could also improve their performance.

Rene Bodjrenou, Luc Ollivier Sintondji, Yekambessun M’Po N’Tcha, Diane Germain, Francis Esse Azonwade, Aymar Yaovi Bossa, Silvère Fernand Sohindji, Gilbert Hounnou, Edid Amouzouvi, and Arthur Freud Segnon Kpognin

Status: open (until 20 Mar 2024)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
Rene Bodjrenou, Luc Ollivier Sintondji, Yekambessun M’Po N’Tcha, Diane Germain, Francis Esse Azonwade, Aymar Yaovi Bossa, Silvère Fernand Sohindji, Gilbert Hounnou, Edid Amouzouvi, and Arthur Freud Segnon Kpognin
Rene Bodjrenou, Luc Ollivier Sintondji, Yekambessun M’Po N’Tcha, Diane Germain, Francis Esse Azonwade, Aymar Yaovi Bossa, Silvère Fernand Sohindji, Gilbert Hounnou, Edid Amouzouvi, and Arthur Freud Segnon Kpognin

Viewed

Total article views: 225 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
178 40 7 225 2 6
  • HTML: 178
  • PDF: 40
  • XML: 7
  • Total: 225
  • BibTeX: 2
  • EndNote: 6
Views and downloads (calculated since 24 Jan 2024)
Cumulative views and downloads (calculated since 24 Jan 2024)

Viewed (geographical distribution)

Total article views: 189 (including HTML, PDF, and XML) Thereof 189 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 25 Feb 2024
Download
Short summary
This study assessed ERA5 reanalysis on runoff, evapotranspiration, water table depth, and soil water content over the Benin basins at spatial scale and monthly time scale. The results showed that the reanalysis simulates well the peaks of mean runoff. It showed the best performance in terms of correlation (>0.50) for runoff, SWC, and ETR. But, the correlations were below 0.5 on the reanalysis for WTD with slight overestimation.