Abstract

Erebus is an exceptional volcano. It rises nearly 4 km above sea-level, dominating Ross Island, and continuously erupts an unusual magma (phonolite) via a persistent lava lake in the summit crater. But it also goes through phases, lasting months, in which this peaceful behaviour is punctuated by violent explosive eruptions that occur a few times a day. Erebus also represents the largest point source of several reactive gases and particles to the Antarctic troposphere. The volcano is monitored more or less year-round by a network of seismometers and other instruments, and is subject to intense field campaigns each year during the austral summer. Drawing on the results of measurements of gas and heat emissions from the volcano, I will review progress in the development of conceptual models for the evolution, transport and degassing of magma beneath Erebus, discuss the origins of the explosive activity, and examine the evidence for impacts of the emissions of NOx, halogens and sulfur on the atmospheric environment.