Sigfús J Johnsen, a long standing IGS member and Seligman Crystal recipient has died at the age of 73
Sigfús was born 27 April 1940 in Iceland. He completed his BSc degree in physics and mathematics from the University of Copenhagen in 1960 and an MSc in experimental physics from the same university in 1966. Following his studies he worked at the University of Copenhagen for thirteen years before he was employed as a ‘docent’ of geophysics at the University of Iceland where he was subsequently appointed as a Professor in 1987. Sigfús moved back to Denmark in 1997 where he has been a key member of what is now the Center for Ice and Climate in the Niels Bohr Institute at the University of Copenhagen. He also maintained a close collaboration with the Science Institute and subsequently the Institute of Earth Sciences at the University of Iceland.
Throughout most of his scientific career, Sigfús was deeply involved in the various research aspects of the Greenland ice cores and the glaciology of the Greenland ice sheet. He was internationally respected for his untiring and dedicated work within that field. He was the main instigator in the development of the Istuk deep ice core drill and participated in 36 ice coring expeditions onto the Greenland Ice Sheet. A great many scientists of various nationalities have learned the art of deep ice coring from Sigfús and have applied that knowledge worldwide. Sigfús was an ever-present “drill-master” and scientific expert throughout the Greenland ice core projects at Dye-3 (GISP), GRIP, NorthGRIP and most recently NEEM.
In addition to various international acknowledgements for his pioneering work on the design and development of deep ice core drills, Sigfús is also renowned for his interpretations of various scientific data on the physics of glaciers and the development of global climate change during the last 150 thousand years. Sigfús has authored in excess of 200 scientific papers including 35 that have been published in Nature and Science. He is in the elite group of scientists defined as ‘highly cited researcher’.
Sigfús was awarded the Seligman Crystal by the Society in 1997 for his outstanding contribution to glaciology. Margrét Þórhildur, Queen of Denmark, appointed him to the Knights Order of ‘Dannebrog’ for his contribution to science. Sigfús was also the recipient of the ‘Hans Oeschger’ medal of the European Geophysical Society (EGS).
In 2010 Sigfús was awarded an Honorary Doctoral Degree from the Department of Earth Sciences, University of Iceland and was made an Honorary Member of the Icelandic Glaciological Society.
He is survived by his wife, Pálína Matthildur Kristinsdóttir, their three children, Kristinn, Jóhann and Valgerður Guðrún, their spouses and grandchildren. A full obituary will be published in a forthcoming issue of ICE.