In terms of manpower and economic resources the seemingly esoteric field of ionospheric research was one of the largest ongoing scientific activities in post war Greenland. Because of its ability to reflect radio waves the ionosphere is of vital importance for radio communication. In the arctic region and especially inside the auroral zone the ionospheric conditions are particularly complex and periods with high absorption of radio waves (“blackout”) occurs frequently and in periods with maximal northern light activity total “blackout” of normal HF radio communication can last up to a week. The necessity of reliable radio communications is of primary importance to commercial fishing and flight, and also for all kinds of military operations. For this reason more than 100 ionospheric stations were being operated all around the world in the mid 1960s. Of these a total of nine or ten active sites were placed in Greenland (Brun 1966).
This subproject will explore the extent and variety of ionospheric research in Greenland. From the very beginning in 1950 the activities grew up as a cooperative Danish-American effort. The first Danish run ionospheric station was erected in 1951 in Godhavn. The year before the U.S. authorities had built their first station in Narsarsuaq, which was eventually handed over to Danish scientists in 1957. From these and other minor facilities ionospheric properties were measured on daily basis and data were sent to the American forecast centre in Boulder, Colorado and the North Atlantic Radio Warning Services. A substantial amount of ionospheric research was also conducted at DTU and DMI in Copenhagen.
In the late 1950s the U.S. military became increasingly more interested in very low frequency (VLF) communication. It is well known that key military communication systems used the VLF band, in particular OMEGA (among other things used for communication with submarines) and SLFCS (the Survivable Low Frequency Communications System developed in the 1960s to provide a secure communications system in the event of nuclear attack). Since the properties of the ionosphere within the auroral zone resembles those that occur during and after a nuclear war the northern region facilitated unique possibilities for testing the reliability and survivability of electronic equipment. Another military interest in VLF ionospheric data was due to its usefulness in atmospheric nuclear test surveillance (Taagholt & Bach 1975; Wilkes & Øberg 1982; Wilkes & Gleditsch 1987).
From 1957 Danish researchers took up studies of arctic VLF radio noise phenomena. In 1964 a new VLF facility was erected at the Danish part of Thule Air Base, which two years later merged with a similar neighbouring U.S. station handed over to the Danes. The research activities were frequently presented as basic science, which is undoubtedly true in some cases. However it is unclear to what extent these efforts related to U.S. and NATO military R&D. Danish efforts in the field is known in many occasions to have been heavily supported by the U.S. NSF, U.S. National Bureau of Standards and various U.S. military bodies. Parallels between American and Danish research interests can bee seen, but what are the links, if there are any? (Brun 1966; Taagholt 1972; Taagholt & Bach 1975; Taagholt 1977; Taagholt 2002; Knudsen 2009).
This subproject will focus on the process of cooperative network building that took place around the Greenland ionospheric research. To what extent did the military presence and interests foster possibilities for ionospheric research? Did it influence the choice of research topics? And how did it affect the scientific ethos? What links existed between Danish efforts and U.S. military interests? Where did researchers go when the military interests declined? A rapid survey suggests that some key-figures during the 1980s (and even before) turned to related environmental topics as ozone layer physics and climate science.
