SUMMARY
The scientific evidence of rainfall and temperature variability with their significant impacts on crops yield isnow stronger than ever. It is even more so on cassava that serves as staple food in most parts of SouthwesternNigeria. Hence, this study, aimed at using Kriging interpolation and other geospatial analysis techniques toassess and map the spatiotemporal variation to investigate the relationship between the yield of cassava andtemperature and rainfall for the period 17 years (1991 – 2007) in South Western, Nigeria. Data for an annualyield of cassava for all the time period were collected from the Federal Ministry of Agriculture, Nigeria,while data on the weather (temperature and rainfall) in the Southwestern states of Nigeria were obtainedfrom the archives of the Nigerian Meteorological Services (NIMET) on an annual basis. ArcGIS (9.2version) was used to analyze the annual temperature, rainfall and cassava yield data. Spatial variation mapswere generated using Kringing method of Interpolation. Existing Map of Nigeria in JP2 format is importedinto the ArcGIS software. The mean rainfall variation maps show the areas which cut cross across Lagos andpart of Ogun states have the highest mean rainfall value range of 134.3 – 137.3 cm while the area havinglowest mean rainfall value range of 107.6 – 110.6 cm. Mean cassava yield geospatial variation map showareas with the highest cassava yield of 16.9 – 17.8 tones with areas with the lowest cassava yield of 9.6 – 10.4tonnes. For mean temperature variation maps, the area which cross cut across through Ekiti and part ofOndo states have the lowest mean temperature value range of 31.3 – 31.4 0 C while areas, mainly in Ogunstate has the highest mean temperature value range of 31.9 – 32.00 C. Mean cassava yield geospatialvariation map depicts the areas with the highest cassava yield of 16.9 – 17.8 tonnes, while the area with thelowest cassava yields of 9.6 - 10.4 tones. The results from these assessment and analysis will help cassavafarmers so as to make better cassava farming plan despite the varying weather condition as to ensure smartagriculture.