High‐latitude eruptions cast shadow over the African monsoon and the flow of the Nile

摘要: [1] Nile River records indicate very low flow following the 1783–1784 Laki volcanic eruption, as well after other high-latitude eruptions. As shown by climate model simulations of significant cooling (−1° to −3°C) Northern Hemisphere land masses during boreal summer 1783 resulted in a strong dynamical effect weakening African and Indian monsoon circulations, with precipitation anomalies −1 −3 mm/day over Sahel Africa, thus producing Nile flow. Future eruptions would significantly impact food water supplies these areas. Using observations River, this new understanding is used support date 939 for beginning eruption Eldgja volcano Iceland, largest past 1500 years.