Return Periods of Drought Intensities in Some Stations in Northern Nigeria

Abstract

This study was on the return periods of the various drought intensities. This study was done with the intension of highlighting the likely return periods of these intensities (invisible, mild, moderate, severe and extreme) and call attention of the various stakeholders like farmers, herders and government at various levels to these. This situation will enable them to put in place individual and collective policies and measures in place to combat the droughts when they arrive. The Bhalme and Mooley Drought Index (BMDI) was used to indentify the intensities for the drought years in eight selected stations in the study area. It also showed the number of times that all intensities appeared during the study period. Thereafter the Return Period statistical tool was applied to the result from the BMDI. The outcome of the application of the return statistical tool being the likely years that all the intensities are to return to the study area. The result showed that the lesser the intensity the higher the likely rate of return. Results also indicated that drought of all intensities are likely to reoccur at faster rates in the region as a whole than within stations without extreme droughts.

KEY WORDS: Return Periods, Invisible, Mild, Moderate, Severe, Extreme, BMDI