Iceland’s Territorial Sea Baselines, Volcanic Eruptions and Sea Level Rise

Abstract Volcanic eruptions can have various consequences, including in the field of the international law of the sea. This article addresses the impact that two volcanic eruptions had on the baselines for measuring the breadth of Iceland’s territorial sea. First, the impact of the eruption in 1918 in Katla was addressed by the Supreme Court of Iceland in 1922 which confirmed a district court decision stating that the territorial sea line was not a fixed or determined line on the sea but changed with avulsions and accretions. Second, the sudden appearance of the volcanic island Surtsey in 1963 affected the drawing of straight baselines along the southwestern coast of Iceland. This article addresses the impact of these eruptions on the territorial sea baseline and explains their relevance for current challenges in international law.