Glaciers
The main requirements for the study sites are that old terrestrial and/or aerial photography is available, and a long series of glaciological and meteorological records exist. Other important factors are the availability of ground survey records, accessibility of the glaciers and the possibility to construct a ground control network. Finally the study sites' relevance for global change studies must be evaluated. The project uses two kinds of study glaciers: 1) study sites, which are used for methodology and monitoring system development, and 2) test sites, in which the monitoring system is tested. The test sites are in the same region as the study sites.
Study sites
The Svartisen ice caps (13E59' E; 66E40' N, 221 km2 and 148 km2) are situated in a maritime climate close to the Atlantic Coast in Nordland, Northern Norway. The altitudinal range is from 7 to 1600 m a.s.l. Annual precipitation in the area is more than 2000 mm along the coast declining rapidly inland to less than 1000 mm on the eastern side of East Svartisen. West Svartisen and East Svartisen have a range of glaciological data going back almost a century, such as changes in front position of two of the outlet glaciers of West Svartisen (Engabreen and Fondalsbreen) back to 1903 and 1906 respectively as well as meteorological data from a nearby meteorlogical station (Glomfjord)going back to 1920. The study site for methodology and monitoring system development is Engabreen (38 km2) in the West Svartisen. Apart from changes in front position, the glaciological data includes mass balance measurements on Engabreen since 1970, as well as mass balance measurements on several of the other outlet glaciers and smaller glaciers for shorter periods. Engabreen is well covered by aerial photographs. The earliest date back to 1945 and there are also photographs from 1968, 1978, 1983 and 1985. In the 1990s, Engabreen was photographed several years, which provides a good basis for comparison between mass-balance studies and stereophotogrammetric outputs. Additional data sets include bottom topography for West Svartisen and surface topography from 1968 and 1985 for West Svartisen. There exist front position maps from several outlets of East Svartisen.
The Hintereisferner is a typical valley glacier with a simple geometry in the Central Eastern Alps, Tyrolia, Austria. The glacier extends from 2500 m to 3700 m elevation and covers about 8 km2. Its volume is about 0.5 km3 of ice and its maximum thickness was 250 m in 1996. It has been studied since the late 19th century. Terrestrial photogrammetric surveys has been made 18 times since 1894 and accurate maps (1:10.000) has been printed in 1894, 1920 and 1979. Original photographs and sketch maps of that time are stored in the archives of various scientific institutes and can be retrieved for re-evaluation with modern techniques. The most complete data exist at the Commission for Glaciology, Bavarian Academy of Sciences, Germany. An uninterrupted series of annual velocity measurements dates back to 1894, the ice depth was determined by mechanical drilling in 1902 and by radio-echo sounding in 1982–96. Annual mass balance measurements were initiated in 1952 and meteorological records of surrounding valley stations started in the middle of the last century. The Institute of Meteorology and Geophysics of the University of Innsbruck operates a research station next to the glacier at 3050 m altitude, housing up to eight people Similar kind of old photographic datasets, maps and complete analyses exist from a neighbouring glacier, Vernagtferner.
Test Sites
The test sites are located on the Svartisen ice cap in Northern Norway and on Oetztal in Austria adjacent to the study sites. The reason for selecting test sites in the same region is to avoid data acquisition and purchasing costs.The Svartisen area provides numerous dissimilar glacier outlets for testing. In a relatively small area, the eastern glaciers are retreating while the western glaciers are expanding. In Oetztal, the nearby glaciers Vernagtferner and Kesselwandferner, are as well studied as Hintereisferner itself, thus providing good comparison data.