Special Issue 1, December 2009
Article Number: 08
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The usefulness of NDVI in the monitoring of drought in the Guinea Savannah Region of Nigeria


E.D. Aweda and Z.D. Adeyewa
Pages 39-45

Abstract—This study employs the use of satellite-derived vegetation index as a drought risk index in the Guinea Savannah region of Nigeria. It examines the relationship between rainfall and the Normalised Difference Vegetation Index (NDVI). An analysis of NDVI and rainfall was done for a period between 19 years (1982 – 2000) across seven (7) stations in this region. The result indicates the anomalies of greenness (i.e. dry and wet periods) for these stations, their respective drought severity indices, and a good correlation between rainfall and NDVI. The degree of wetness and dryness is indicated while it also shows that this region is beginning to experience drought due to the increase in dryness and severity index. A number of recommendations are made that would help to upgrade the methodology as a very useful and effective tool for drought early warning in other regions of Nigeria especially in the Guinea region where drought remains a recurring threat. These include real time observations in various stations in this region and the integration of NDVI with an indicator such as GIS amongst others.

Keywords—anomalies, drought, drought severity, NDVI.