During the past 220 years, prominent signals of non-sea salt sulfate ion (nssSO42-) concentration exceeding the background level, including both marine biogenic and anthropogenic SO42-, were found in shallow ice cores from site H15in East Antarctica and Site-J in southern Greenland.They were mostly correlated with past explosive volcanic eruptions. On the basis of this result and published results of shallow ice cores and snow pits at various locations on the Antarctic and Greenland ice sheets, eight common signals were found, of which six were assigned to the following explosive eruptions: El Chicho´n, Mexico, in 1982; Agung, Indonesia, in 1963; Santa Maria, Guatemala, in 1902; Krakatau, Indonesia, in 1883; Cosiguina, Nicaragua, in 1835; an unknown volcano between 1831 and 1834; Tambora, Indonesia, in 1815; and an unknown volcano in 1809.Volcanic eruptions which have a potential to imprint their signals in both the Antarctic and Greenland ice sheets were characterized by (1) location in low latitudes between 20° N and 10° S, and (2) eruption column height ≥25 km, corresponding to a volcanic explosivity index (VEI) ≥5.
The Annals of Glaciology is a peer-reviewed, thematic journal published 2 to 4 times a year by the International Glaciological Society (IGS). Publication frequency is determined and volume/issue numbers assigned by the IGS Council on a year-to-year basis and with a lead time of 3 to 4 years. The Annals of Glaciology is included in the ISI Science Citation Index from volume 50, number 50 onwards.
Themes can be on any aspect of the study of snow and ice. Individual members can make a suggestion for a theme for an Annals issue to the Secretary General, who will forward it to the IGS Publications Committee. The IGS Publication Committee will make a recommendation for an individual themed Annals issue, together with a potential Annals Chief Editor for that issue, to IGS Council. The IGS Council will make the decision whether to proceed, taking into account the spread of topics and the overall capacity for publication of pages in Annals.