Analysis of Climate Variability in the Central District of Taraba State, North-East, Nigeria

Abstract

Climatic maps have been very difficult to generate in Nigeria, not because of lack of knowledge or expertise, but due to dearth of climatic data. Most of the existing climatic maps are either not reliable or too generalized since Nigerian Meteorological Agency (NIMET) climatic data which is the only reliable climatic data are available only in the state capitals and which were often used to generate climatic maps. In this study, DivaGIS, WorldClim, NASA Power Project and globalweather climatic data of rainfall, temperature, relative humidity and solar radiation were used to generate the spatial patterns, trends and seasonal pattern of each of the aforementioned climatic elements in Taraba State Central District; comprising Bali, Gassol, Gashaka, Gembu, Kurmi and Sardauna LGAs. The results were presented in charts and using the bar chart and the kringing tools of Microsoft Excel package and ArcGIS 10.5 software respectively. Spatial pattern of rainfall of the area revealed that the rainfall pattern are influenced by relief and latitudes as Sardauna which is on the plateau in the South has more rains than Gassol in the North. Mountainous and highland areas were also found to have higher rainfall than the immediate environment. Trends in rainfall was decreasing in Bali, Gashaka and Sardauna LGAs. Rainfall is high from June to September when minimum of 200 mm monthly rainfall are received in all the five LGAs. The spatial pattern of temperature is inversely related to that of rainfall, while trends in temperature is increasing in all the LGAs. Relative humidity has similar spatial/seasonal patterns with that of rainfall, but showing decreasing trends in all the LGAs except Kurmi LGA. The spatial pattern of solar radiation was found to be affected by the aspects of the area as Kurmi LGA at the western side recorded highest amount of solar radiation. The pattern of solar radiation in the study area is seasonal because solar radiation is low (less than 20 mj/m2) in all the LGAs except Kurmi during the rainy season (June – October). It was recommended that ground station climatic data which covers larger areas than in-situ climatic data that are only available in State capitals should be encouraged among the climate analysts to alleviate the problems associated with dearth in in-situ climatic data.