This paper reports on a quantitative simulation to measure the possible implications of climate change in Africa. The simulation employs forecasts of future atmospheric carbon dioxide for 2100, drawing implications for agricultural productivity and economic performance in Africa.The paper makes the following main points:African farmers have adapted to a certain amount of climate variability, but climate change may well force large regions of marginal agriculture out of production in Africathe agriculture sector is a major contributor to the current economy of most African countries, averaging 21% and ranging from 10% to 70% of the GDPevidence suggests that African agriculture is very vulnerable to climate changethe simulation suggests that the impacts of climate change can range from a potential loss of $25 billion to a loss of $194 billion per year, depending on the climate sensitivity usedthe most pessimistic forecast suggests that African countries may lose 47% of their agricultural revenue because of global warmingdespite the large size of these climate impacts, it should be noted that the impacts are expected to be a small fraction of future GDPagriculture should be a small fraction of GDP in Africa by 2100, with the expected growth in other sectors of the economythe damage from climate change to African agriculture is expected to range from 0.13% to 2% of GDP by 2100.[adapted from author]