ADHI: the African Database of Hydrometric Indices (1950–2018)
The study of large tropical river regimes is extremely useful for evaluating continental land surface models and remote sensing data products, and contributes to the development of operational flood and drought monitoring systems.
In addition, the density of monitoring networks on the African continent is lower compared to other continents. This is a serious issue for hydrologists since the acquisition and experimental analysis of data remain central to understand hydrological processes, their spatio-temporal variability and measure the impacts of climate change on the regime of large African rivers, for example.
For this, the constitution and opening of the African Dataset of Hydrometric Indices (ADHI) is of major scientific relevance.
It aims to provide access to a set of hydrometric indices calculated from data from measuring stations with daily flow data. Covering the last 68 years, this information is very useful to assess the variability of African river flows.
The proposed indices are largely calculated from the SIEREM database and the Global Runoff Data Center (GRDC) station collection. The hydro-climatological data contained in SIEREM are the legacy of the former Laboratoire d'Hydrologie de l'Office de la Recherche Scientifique et Technique Outre-Mer (ORSTOM; now Institut de Recherche pour le Développement, IRD, France). It should be noted that in addition to daily data, the SIEREM database also contains rainfall and instantaneous flows for hundreds of small experimental catchments established mostly in the 1950s and 1960s. Most of the hydrological stations in French-speaking countries have been established and managed for decades by the ORSTOM Institute. At the time of data processing, the SIEREM database included a total of 1046 flow series, many of which are duplicates of the same monitoring station but for different periods.
Since 2020, they are now accessible in the DataSuds data warehouse for the international community while respecting the confidentiality of the original records when they are not allowed to be shared publicly by national authorities.
Number of available stations per year with less than 5 % missing data (a) and number of stations available for different record lengths (b)
