Effect of Carbon Dioxide Concentration on Cereal Yield in Sudan

To estimate the long-term effect of carbon dioxide (CO 2 ) emission on cereal yield in Sudan, we employed an autoregressive distributed lagged (ARDL) bound test for cointegration analysis. The ARDL results reveal evidence of cointegration between the dependent variable (cereals yield) and two independent variables (CO 2 emission) and agricultural GDP. The estimation results of the error correction model indicate that change in CO 2 has a positive and significant impact on the cereal yield in the long and short terms, as 1% increase in CO 2 leads to a cereal yield increase by 3% in the short term and by 0.7% in the long term. This result adds two important findings to the existing literature: First, the positive impact of CO 2 on cereal yield in Sudan supports previous research findings in other countries of warm and arid climates. Second, the effect of CO 2 on cereal yield differs from short to long term, as our finding indicates that CO 2 has a greater positive effect in the short term compared to that in the long term, implying that the effect of CO 2 on cereal yields is not linear, as commonly perceived, but it decreases as time duration extends to longer periods. This may be due to the CO 2 effect on global warming that emanates from cumulative CO 2 concentration, which leaves a disproportionate impact on crops over time.