  The impact of extreme climate such as drought and flooding on agriculture,
tourism, migration and peace in Nigeria is immense. There is the need to study
the trend and statistics for better planning, preparation and adaptation. In
this study, the statistical and temporal variation of climatic indices
Standardized Precipitation Index (SPI ) and Standardized Precipitation
Evapotranspiration Index (SPEI) were computed for eighteen (18) stations
covering four climatic zones (Sahel, Midland, Guinea Savannah and Coastal) of
tropical Nigeria. Precipitation, minimum and maximum temperature from 1980 -
2010 obtained from the archives of the Nigerian Meteorological Services were
used to compute both the SPI and SPEI indices at 1-, 3- 6- and 12-month
timescales. The temporal variation of drought indices showed that droughts were
more prominent at 6- and 12-months timescales. SPI and SPEI were found to be
better correlated at longer timescales than short time scales. Predominant
small, positive and significant trend across the region suggest an increasing
trend due to climate change.
