Effect of Climate Change on Maize Supply in Ghana, 1970-2002

Abstract

Societies which depend upon agriculture for their livelihood may face the perils of climate change (Global Wanning), especially developing countries in the tropics and subtropics where some crops are already near their maximum temperature tolerance and where dry land and non-irrigated agriculture predominate. Yields will tend to decrease with even nominal amounts of climate change. Agriculture in Ghana is largely rain fed, therefore changes in climate in the form of changes in rainfall for example, may affect agricultural supply especially crops, maize inclusive. This study examines the effects of climate change, using rainfall and temperature as climate variables, on maize supply in Ghana. Annual time series data on temperature, rainfall, and output of maize, prices o f maize, rice, cassava and fertiliser covering the period 1970-2002 are used. The error correction model and Granger Causality Test were employed in the analysis. The results of the study show that climate change in the form of change in rainfall exerts a statistically significant effect on supply of maize. The study further confirms that rainfall is essential during crop growth, and the critical major period o f rainfall is the best time to plant to avoid water stress and pest infestation. The study closes with some policy recommendations and suggestions for future research.