Abstract:
Climate variability is among the major environmental challenges of the 21st century. Temporal
and spatial rainfall and temperature variation during cropping season induces an important
challenge to sorghum yield and in turn to food insecurity. Therefore, this paper intends to assess
climate variability and its effects to sorghum yield of Miesso woreda. Both Primary and
secondary data were used. Station data of Temperature and rainfall for the period of 1991- 2019
were used for analysis. Data have been analyzed using coefficient of variation, precipitation
concentration index and regression model. Furthermore, Mann-Kendall test and Standard
normal homogeneity test was used to detect the variability and time series trend of rainfall and
temperature. Result revealed that, 33.3 0C the highest amount of maximum temperature and
whereas 17.9 0C was lowest amount of minimum temperature. The coefficient of variation of
maximum temperature was 1.77 and the coefficient of variation for minimum temperature was
1.36. The highest amount of rainfall was recorded in summer season and the lowest was
recorded in winter. The coefficient of variation of rainfall was highest in winter with CV 98.7
and lowest in summer season. Therefore, the summer season had highest amount of rainfall with
smallest variation. The MK test shows that there is an increasing trend for both minimum and
maximum temperature. The MK test for minimum temperature is statistically significant during
the season of autumn and insignificant on spring, summer, winter, and annual period. In the case
of rainfall all seasons indicate decreasing trend. Monthly results of coefficient of variation
values indicated high rainfall variability. Correlation analysis result showed that the
relationship between climate variables and sorghum yield, rainfall and minimum temperature
have positive correlation with sorghum yield, whereas the correlation between maximum
temperature with sorghum yield is negative. annual regression analysis result indicates that
climate variables accounts for only 2.28% of sorghum yield variation. Whereas, the summer
climate variables accounts for 31.28% sorghum yield variations and the remaining 68.72% of
the variation of sorghum yield could be explained by other climatic and non-climatic factors.
Since there is strong irregularity of rainfall in Miesso Woreda and climate variability has
negative effects on sorghum yield, there is a need to formulate comprehensive policies, and
strategies that specifically address effects of climate variability and mitigation mechanisms
