Development of the Niger Basin Drought Monitor (NBDM) for early warning and concurrent tracking of meteorological, agricultural and hydrological droughts

Okpara, J. N.; Ogunjobi, Kehinde; Adefisan, E. A.

Development of the Niger Basin Drought Monitor (NBDM) for early warning and concurrent tracking of meteorological, agricultural and hydrological droughts

Autores

Okpara, J. N.

Ogunjobi, Kehinde

Adefisan, E. A.

Editor

MDPI

Descripción

Drought remains a phenomenal disaster of critical concerns in West Africa, particularly within the Niger River Basin, due to its insidious, multifaceted, and long-lasting nature. Its continuous severe impacts on communities, combined with the limitations of existing univariate index-based monitoring methods, worsen the challenge. This paper introduces and evaluates a Hybrid Drought Resilience Empirical Model (DREM) that integrates meteorological, agricultural, and hydrological indicators to improve their concurrent monitoring and early warning for effective decision-making in the region. Using reanalysis hydrometeorological data (1980–2016) and community vulnerability records, results show that the DREM-based composite index detects drought earlier than the Standardized Precipitation Index (SPI), with stronger alignment to soil moisture and streamflow variations. The model identifies drought onset when thresholds range from −0.26 to −1.19 over three consecutive months, depending on location, and signals drought termination when thresholds rise between −0.08 and −0.82. The study concludes that the DREM-based composite index provides a more reliable and integrated framework for early drought detection and decision-making across the Niger River Basin, and hence, has proven to be a suitable drought monitor for stakeholders in the Niger Basin which can be relied upon and trusted with high confidence.