 This means that the island is highly geologically active with many volcanoes including Hekla, Eldgjá, Herðubreið, and Eldfell.The volcanic eruption of Laki in 1783–1784 caused a famine that killed nearly a quarter of the island's population.In addition, the eruption caused dust clouds and haze to appear over most of Europe and parts of Asia and Africa for several months afterward, and affected climates in other areas.