Climate change was defined as a statistically significant variation in the mean state of climate. Accordingly, with regards to rainfall, a working hypothesis that reads as: there is a statistically significant change (increase/decrease) in the mean annual and seasonal rainfall values at weather stations was forwarded for testing. Eight years (2001-2008) annual and seasonal rainfall data of 17 weather stations from most parts of Ethiopia were used for the purpose. Setting the significance level at 0.05, the simple correlation and regression techniques were used to reach results. Most stations from the western part of Ethiopia were seen to exhibit statistically significant increasing trend in annual rainfall receipt. Albeit not significantly, northward and eastward from here, the receipt was also seen tending first to increase then decrease. This tendency was observed to overlap with the traditional distribution of rainfall in the country. The alternating of dry and wet years and the more localizing of wet years than dry years were identified. The four seasons considered observed statistically significant and not significant increasing and decreasing trends in seasonal rainfall receipt at the respective stations. Most conspicuously, 94% of the total number of stations considered in this study show increasing trend in autumn rainfall receipt. Based on the findings of the study, some conclusions policy makers may be taking into consideration were finally drawn.

 

Key words: Annual, Ethiopia, rainfall, seasonal, significant.