Trends in temperatures in Sub-Saharan Africa. Evidence of global warming

Abstract

Climate change has become a serious environmental matter of global concern. This paper attempts to verify if there is climatic change in Sub-Saharan Africa with the help of monthly station data from January 1901 to December 2020 on the mean temperatures of 48 countries of Sub-Saharan Africa. To do this, we employ fractional integration to account for the data's probable long memory feature. However, because other statistical features such as linear trends and seasonality might also be present in the data, we propose a broad framework that treats these three characteristics (long-range dependence, time trends, and seasonality) in a unified treatment. We first note that long memory is an observed feature in the data and using the original data, the time trends are found to be significant in Southern and Eastern countries, with higher coefficients being observed when the post-War II data are employed. When looking at the anomalies with respect to selected periods, long memory is found in all cases, and a higher number of trends are detected. Thus, 41 countries show significant time trends, with the values being higher again in the post WW2 sample, suggesting that industrialization might have contributed to global warming. The results also indicate some degree of heterogeneity across the African countries.