Most of the glaciological work in 1951 was carried out on Nigardsbreen in Jostedalen, and in Jotunheimen. A party was stationed at Nigardsbreen and carried out photogrammetric measurements of the movements of the glaciers. In addition the meteorologist, Ole Amble, conducted measurements of the katabatic wind on Nigardsbreen. This was accomplished by shooting small clouds of smoke into the air and tracing them with a film camera..
Last year’s measurements of the changes in volume of Storbreen in Jotunheimen were continued. A deficiency of 0.5 × 106 tons per km.2 was recorded in spite of the cold summer. This is due to the exceptionally small quantities of precipitation in the mountains last winter.
Professor H. U. Sverdrup, at whose request this report is written, has asked me to mention the maps showing the accumulation of snow, which the Norwegian meteorological authorities are preparing every month during winter and spring. The maps show the total quantity of accumulated snow as a percentage of a normal year. They are not based on direct measurements, but on observations at the permanent meteorological stations. They cover the whole country and are designed for three heights, 400 m., 800 m. and 1200 m. In the glacier regions maps will also be prepared for heights of 1600 m. and 2000 m. These latter will be important for the study of the variations of the glaciers in Norway. During the Symposium of the I.U.G.G. in Brussels some weeks ago the meteorologist A. Jakhelln delivered a lecture giving a more detailed report on the maps.
I am also enclosing a copy of a rubbing which I made on a remainder of dead ice at Nigardsbreen. The dead ice is now to be found about 1000 m. from the edge of the glacier, forming an island in the water at the front of the glacier. From photographs of older date it is apparent that it had been separated from the living glacier as early as about 1933, and thus it is about eighteen years old. The crystals were of an equal size all over the area of 2 m.2 which was open for observation. The remainder was covered by a bed of sand, 50 cm. thick.Footnote *