Bjørn G. Andersen


Bjørn Grothaug Andersen was a Norwegian professor of Quaternary geology and glaciology who made foundational contributions to glacial geology and the understanding of climate change.

Life and career

Andersen was the son of Knut Severin Andersen b. Grothaug, from Hornindal in Nordfjord, who was a gardener in Stavanger, and Elise Andersen b. Rafoss from Stavanger. Because his father was a gardener they had a car, which was rare at the time, and using this they went on skiing in the winter and fishing in the summer. He enjoyed going for long skiing tours in the mountains in Stavanger, when he was young, and several times he crossed Trollgaren in Ryfylke, this marvelous moraine that is appropriate to its name. He wondered how it was formed, and was told by the local farmer that it was really Trolls that had set up the meandering fence of huge boulders, far above the tree line. The curiosity for this natural phenomenon in addition to many others in turn led to his interest for the Ice Age.
In 1951 he married the physiotherapist Astrid E. Kruse Andersen. After a Research Fellowship at Yale University under Richard Foster Flint in 1954–1956, Andersen was a professor of Quaternary geology at the University of Oslo from 1956 to 1970, then at the University of Bergen from 1970 to 1982. Then he returned to the University of Oslo and worked there for 9 years until retirement. He headed the geological institutes both in Oslo and Bergen. He was responsible for the geological education of more than 30 year groups of students, and he continued to participate in academic society until autumn 2011, when he had developed cancer and was in poor health. Andersen was a sought after lecturer and was acclaimed by his students, some of whom he kept in contact with until his death in January 2012.

Contributions to Quaternary geology

At the University of Bergen, Andersen played a central role in building up the study of Quaternary geology. His students and the university benefited from his international contacts and he conducted filed trips to the Antarctic, South America and New Zealand. Most of all his contribution was to reveal the foundation of Scandinavian landscapes.
Andersen's first expedition to the South Pole came in a period of small Norwegian interest in the Antarctic after the great achievements of Roald Amundsen in 1911–1912. Andersen was the second Norwegian to visit the Pole after the Amundsen expedition. An American expedition which reached the Pole a week before him honored his achievements by naming a mountain escarpment Andersen Escarpment after him.
During the fieldworks for his Master's thesis "Om isens tilbaketrekking i området mellom Lysefjorden og Jøsenfjorden i Ryfylke", with Werner Werenskiold as advisor, he found among other things that Trollgaren was a moraine, and that it was formed in the early Holocene, probably about 11,000 years ago. Here he met his youth curiosity. Andersen broke new ground both methodologically and theoretically with this work. He developed a method for stereoscopic analysis of aerial photos in the assessment of moraines. During the 1950s and 1960s he assessed the moraines in most of Norway, from Lindesnes to Troms. The assessment of the moraines of Jæren and the rest of the south coast of Norway was the basis of his PhD thesis "Sørlandet i sen- og postglacial tid", under guidance of Olaf Holtedahl, defended in 1960.
Andersen discovered an until then unknown area of Rogaland containing rock of the Cambrian-Silurian age on a much lower level than the surrounding bedrock. His collected fossiles from this area were deposited in the Paleontologic Museum at Tøyen in Oslo. In this material Professor Gunnar Henningsmoen discovered an until then unknown trilobite species, which was given the name for Andersen. During this fieldwork in the Lysefjord area, Andersen developed a method for determination of climatic conditions from the reconstruction of Ice Age glaciers which is still used by geologists and geographers.
Andersen's first paper is one of the most basic papers in Norwegian glacial geology, even though it was published before C-14 dating was available. The Younger Dryas glacier of the Lysefjord was reconstructed in three dimensions and compared with the glaciers in Greenland today. Further, the highest side moraines were used to determine the equilibrium line of the paleo-glaciers and thus its lowering by comparison with today's glaciers. In this way he was able to estimate the decrease of summer temperature with surprising accuracy. These decreased temperatures were in compliance with the findings of botanist Knut Fægri at the Younger Dryas glacier of Jæren.

Mountain preservation and hiking

Andersen was an active mountain walker bouth professionally and for leisure. As young he went on hikes together with his father and his older brothers. Later he trawled the mountain wilds with his wife in areas like Jotunheimen, Rondane and Dovrefjell, and professionally, as Quaternary geologist he mapped the major mountain regions in Norway during the 1950s and 1960s. He also had a major part in the preservation efforts in Øvre Pasvik, Saltfjellet–Svartisen, Børgefjell, Jostedalsbreen and Hardangervidda, among others. His work in these areas was an important input in the struggle for opening the National parks there.

After retirement

Andersen was a dedicated glaciologist all of his adult life. He accompanied a party of scientists doing field studies in Chile in 1991–99, and in New Zealand in 2000–08, led by the American Quaternary geologist Professor George H. Denton of the University of Maine. These studies led to a series of publications, among them papers in the prestigious international scientific journals Nature and Science. This was in addition to two books on glacial geology, one about the Ice Age in Norway: Istider i Norge, 2000, and an international textbook on the Ice Age World in 1997.
Late summer 2005, Andersen went on a trip to Greenland together with George Denton and a group of scientists. They wanted to measure the ice coverage in connection to climatic change.
In the summer of 2011 Andersen presented the results of the New Zealand research at a geological conference in Switzerland. There he also discussed the continuation of his Norwegian fieldwork, and in September–October joined a joint Norwegian-US exploratory expedition to Lysefjord led by Jan Mangerud and George Denton which investigated the application of a new dating method to the moraines he charted in the 1950s for his Master's.

Honors

Scientific publications