Geospatial assessments on the relationship between climate variability and crop production are essential for planning adaptation programs to climate change impacts on agriculture production. However, there are limited geostatistical studies related to climate variability’s impacts on crop production, specifically in Malawi. Therefore, this study assesses the effects of climate variability and change on crop production of maize and sweet potato in Mangochi district, Malawi, through the use of geostatistical methods. The study will bring a new scientific perspective in the research area and is important in the development of adaptation programs to climate change impacts on Malawian crop production. Firstly, the analysis was done by using descriptive statistics, multiple regressions, and ANOVA. Then geostatistical methods are applied to assess changes in the patterns of precipitation and temperature and corresponding changes in the maize and sweet potato crop production in Mangochi district, Malawi. Surfaces depicting changes in the total precipitation and average monthly temperature from 2009 to 2018, and changes in maize and sweet potato crop yield from 2009-2010 to 2018-2019 crop years are generated through Ordinary Kriging methods. Performance evaluation of the model is also done. An assessment of the relationships between the surfaces of different precipitation and temperature seasons and the surfaces of varying maize and sweet potato yield seasons is finally done. The results display that there is a significant correlation between precipitation and temperature changes and maize and sweet potato yield changes with notable correlation coefficients and similarity in the patterns. Substantial conformity of the high precipitation and lower temperature zones to the high maize and sweet potato yielding zones is also depicted. However, further exploration of geospatial techniques is needed for a realistic assessment of the effects of climate variability and change on crop production.

Chapter 1: Introduction 1
Chapter 2: Literature review 7
Chapter 3: Study Area and Methods 15
Chapter 4: Results and Discussion 31
Chapter 5: Conclusion and Suggestions 65

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