Publisert 18.02.2016 , sist oppdatert 09.01.2023

Length change measurements

Length change measurements from reference point at Engabreen 23rd October 2021. Photo: Stein Engen / NVE.

Glacier length changes are a proxy for glacier area changes, and there by the result of mass balance changes. Long-term records indicate long-term volume changes. Length change records from a number of glaciers indicate the development of all the glaciers.

Background and method
The first systematic lengt change measurements were initiated around 1900 at Jostedalsbreen, Folgefonna, Svartisen, Okstindbreen, in Skjomen and in Jotunheimen by J. Rekstad at Bergen Museum (now Univerity of Bergen), P.A. Øyen at University of Oslo and Adolf Hoel at Norwegian Geological Survey . The monitoring was continued by K. Fægri and W. Werenskiold, and later by Olav Liestøl and Jon Ove Hagen at Norwegian Polar Institute. Since 1994, Hydrology Department at NVE has been responsible for the monitoring programme.

The distance from a fixed point (cairn, painted mark, reference bolt, or similar) to the glacier is measured in the same direction annually. The line should preferably represent a central flow line.

The length change observations are stored in NVE data base and are available under "Glacier data". The results are published in NVE report serie Glaciological investigations in Norway, and reported to World Glacier Monitoring Service (WGMS) and  published in their 'Fluctuations of Glaciers’ (FoG). 

 Litterature (selected)

Andreassen, L.M., H. Elvehøy, B. Kjøllmoen, and J.M.C. Belart, 2020. Glacier change in Norway since the 1960s - an overview of mass balance, area, length and surface elevation changes. Journal of Glaciology, 1-16https://doi.org/10.1017/jog.2020.10.

Fægri, K. 1940: Forandringer ved norske breer 1937-39. Bergen Museums Årbok 1939-40. Naturvidenskapelig rekke. Nr 3.

Hoel, A. & Werenskiold, W.1962: Glaciers and snowfields in Norway. Norsk Polarinstitutt Skrifter Nr.114, 291 s.

Kjøllmoen, B. (ed.), 2019: Glaciological investigations in Norway in 2018. NVE Report No.46/2019.

Liestøl, O. 1964. Noen resultater av bremålinger i Norge i 1963. Norsk Polarinstitutt Årbok 1963., s. 185-192.

Rekstad, J., 1904: Fra Jostedalsbræen. Bergens Museums Aarbog 1904, No 1, 1-69.

Rekstad, J., 1910: Forandringer ved norske breer i aaret 1908-09. Bergens Museum Årbok 1910, 2-12.

Øyen, P.A., 1906: Klima- und Gletcherschwankungen in Norwegen. Zeitschrift fur Gletcherkunde, Eiszeitforschung und Geschichte. 1: 46-61.