Ragnar Stefánsson (1938 - 2024)

 Ragnar Stefánsson (1938 - 2024)

Our friend and colleague Ragnar Stefánsson passed away on 25 June 2024 at the age of 85.

For decades Ragnar Stefánsson was the face of seismology and earthquakes in the public life in Iceland, a country on a plate boundary where seismic and volcanic activity is a part of everyday life. Ragnar “skjálfti” would be on the screen or the front page of the papers every time there was a significant earthquake or an eruption worth commenting on. He was an iconic person, known to everybody.

Ragnar was born in Reykjavík on 14 August 1938 and got his primary education there. After his high school years he went to Uppsala University in Sweden to study mathematics and physics and got a fil. cand. degree in geophysics in 1962. He then moved back to Iceland to take up a position of head of the Division of Geophysics at the Icelandic Meteorological Office. He continued his graduate work in Uppsala in 1963 and obtained a fil. lic degree in 1966 under Markus Båth. The subject of his thesis was the focal mechanisms of two large earthquakes on the Mid-Atlantic Ridge system, the magnitude 6.9 event of 1962 on the Vema Fracture Zone, and the magnitude 6.9 event of 1963 off the north coast of Iceland. Based on a study of seismograms from numerous seismic stations distributed around the globe Ragnar was able to demonstrate strike- slip faulting as the source mechanism of these events. This study was published in Tectonophysics in 1966, a year before the classical paper of Sykes (1967) that explained transform faulting on the Atlantic plate boundary.

After his PhD Ragnar returned to the Icelandic Meteorological Office as a head of the Geophysical Department. The main task was the operation of the small seismic network, maintenance and interpretation of seismograms. The increasing volcanic activity in the sixties and seventies required attention, with eruptions of Surtsey, Hekla, and Heimaey. A new generation of analog seismographs allowed expansion of the seismograph network in cooperation with the research group at the Science Institute of the University of Iceland and other groups. The new network of over 40 stations allowed more accurate location of epicenters throughout the whole country.

In the late 1980s, when the digital revolution got underway in seismology, Ragnar had the initiative to join forces with the leading seismologists in the other Nordic Countries, Norway, Denmark, Sweden and Finland, to design and implement a state-of-the-art seismograph network in the South Iceland Seismic Zone, the transform plate boundary linking the rift zones of Iceland to the mid-Atlantic ridge system. This is the source area of the most destructive earthquakes in Iceland ́s history, and there were indications that a new series of large earthquakes was imminent. The project got funded jointly by the Nordic Countries and the new seismic system, the SIL-system, became operational around 1990. The emphasis was on automatic date analysis and to lower the detection threshold as much as possible. The data and results were made publicly available on a webpage in order to stimulate the public interest and awareness. The project was highly successful, and the network was expanded to the rest of the country in the following years. The IMO seismic website, vedur.is, is one of the most visited ones in Iceland.

In 2004 Ragnar moved to Svarfaðardalur in North Iceland to start up and head a new Research Branch for the Icelandic Meteorological Office at the University of Akureyri and in 2006 he became a research professor in Earthquake and Volcanic Hazards at the University of Akureyri until his retirement in 2008.

The first published results of the SIL-system operation (Stefánsson et al., 1993) confirmed the indications of an impending series of large earthquakes in the South Iceland Seismic Zone. The earthquake sequence began on the National Day, June 17 in 2000 with an M 6.5 earthquake followed by a series of triggered events and aftershocks along a 90 km long section of the plate boundary. This anticipated earthquake sequence strengthened the general belief in Iceland that earthquakes could be forecast given the attention and the quality data provided by the new SIL-system. The SIL-project was subsequently followed by several co-operative projects of large groups of European seismologists where Ragnar played a leading role, and funded mostly by the European Union. These projects, such as FORESIGHT and PREPARED, were designed around different aspects of earthquake and volcano forecasting and monitoring. The projects led to numerous peer-reviewed research papers. Ragnar spent his years after retirement summarizing the results in two books, one in English for the scientific community, „Advances in Earthquake Prediction, Research and Risk Mitigation“, published by Springer-Verlag in 2011, and the other in Icelandic, meant for the local population „Hvenær kemur sá stóri?“ (When will the big one occur?), He got the Icelandic literature price for academic books in 2022 for this book. A book by Ragnar on his personal life was published in 2013.

All through his life, Ragnar took an active part in the political scene in Iceland. The cold war following the Second World War had a great polarizing impact on Icelandic politics, and the NATO military base in Iceland was an important issue. Ragnar became well known for his persistent resistance against the American military presence in Iceland. This opposition did not, however, prevent him from running a WWSSN seismic station in Akureyri for the US Geological Survey. The main mission of the WWSS Network was to provide a check on the Russian development of nuclear weapons. Ragnar was the chairman of Fylkingin, the socialist campaign league, during most of 1966 – 1984. In 1999 he was also one of the founders of the political party VG, a left, green party. VG subsequently participated in the Government of Iceland for a good part of the time period until 2024, often in the leading role. After moving to Svarfaðardalur Ragnar participated in the local politics there. He was one of the founding members and chairman of Framfarafélag Dalvíkurbyggðar (Dalvík progressive association), and during 2003 – 2008 also the chairman of Landsbyggðin lifi (Rural communities association).

Ragnar had a large family. With his first wife, Astrid Malmström, a college teacher, whom he married in 1961, he had three children, Kristína, Stefán Áki, and Gunnar Bjarni. With Björk Gísladóttir he had a daughter, Bryndís Hrönn. With his second wife, Ingibjörg Hjartardóttir, a writer, whom he married in 1990, he had two stepsons, Hugleikur and Þormóður. He had altogether 10 grandchildren. Ragnar Stefánsson was a colourful person who enriched the life of people around him. He is missed by his family, friends, colleagues and the Icelandic people.

Páll Einarsson and Steinunn S. Jakobsdóttir