Skip to main content Accessibility help
×
Home
Hostname: page-component-78bd46657c-2z7pd Total loading time: 0.204 Render date: 2021-05-06T14:10:07.643Z Has data issue: true Feature Flags: { "shouldUseShareProductTool": true, "shouldUseHypothesis": true, "isUnsiloEnabled": true, "metricsAbstractViews": false, "figures": false, "newCiteModal": false, "newCitedByModal": true }

Throughflow water velocities in Austre Okstindbreen, Norway

Published online by Cambridge University Press:  30 January 2017

A. D. Knighton
Affiliation:
Department of Geography, University of Sheffield, Sheffield S10 2TN, England
W. H. Theakstone
Affiliation:
Department of Geography, University of Manchester, Manchester M13 9PL, England
Rights & Permissions[Opens in a new window]

Abstract

Type
Correspondence
Copyright
Copyright © International Glaciological Society 1978

Sir,

The velocity with which melt water moves through a glacier is largely determined by the internal drainage characteristics of that glacier. Measurements of throughflow times were made in August 1977 in the ablation area of Austre Okstindbreen, the main outlet glacier of the Okstindan ice cap in Norway (lat. 66° 02' N., long. 14° 19' E.). Instantaneous injections of fluorescein dye were made at three sites where supraglacial streams entered moulins (Fig. 1). Largely because of problems associated with dissipation of the dye trace, only one reliable result was obtained, that being from the point furthest up-glacier at site 1. Using a straight-line distance between the injection and outflow points of 1.4 km, a throughflow velocity of 1.8 m s-1 was calculated. Dye was injected into the moulin at 13.40 h, a time of day when throughflow velocities may be at a maximum (Reference Behrens, Behrens., Bergmann, Moser, Ambach and Jochum.Behrens and others, 1975)· Less reliable estimates of throughflow velocity ranged from 0.6 to 1.9 m s-1 for site 2, whilst the dye trace was never sighted at the outflow point after repeated injections at site 3.

Fig. 1. Map of the lower part of Austre Okstindbreen with points of dye injection indicated. Surface contours are given in metres. The main directions of surface drainage are shown, with the dashed line indicating a major drainage divide.

The measured velocity of 1.8 m s-1 appears relatively high when compared with similar measurements made elsewhere. Reference StenborgStenborg (1939) obtained average velocity values ranging from 0.5 to 0.7 m s-1 over distances of up to 1.7 km from the snout of Mikkaglaciären. Reference Behrens, Behrens., Bergmann, Moser, Ambach and Jochum.Behrens and others (1975) reported values for the Hintereisferner of between 0.47 and 1.11 ms-1 which were consistent over two summer seasons, suggesting that the internal drainage system changed little over that period; a diurnal cycle of throughflow velocities at Hintereisferner included a maximum at about 14.00 h and a minimum at 05.30 h. Reference Krimmel, Krimmel, Tangborn and Meier.Krimmel and others (1973) found that, at South Cascade Glacier, the mean velocity of dye tracer injected into moulins (0.29 m s-1) was within the velocity range of supraglacial streams (0.17 to 0.42 m s-1). The high velocity value recorded at Austre Okstindbreen presumably reflects unimpeded drainage between site 1 and the glacier snout, which in turn probably implies deep penetration of the moulin and the existence of a well-defined subglacial stream. It is interesting to note that mean velocities calculated from measurements made with a current meter in several of the surface streams rarely exceeded 2 ms-1, suggesting that the drainage characteristics of surface and sub-surface melt water are similar in certain respects, the presence of flow in some form of channel being of particular importance.

References

Behrens, H., and others. 1975. On the water channels of the internal drainage system of the Hintereisferner, Ötztal Alps, Austria, by Behrens., H. Bergmann, H. Moser, H. Ambach, W. and Jochum., O Journal of Glaciology, Vol. 14, No. 72, p. 375-82.CrossRefGoogle Scholar
Krimmel, R.M., and others. 1973. Water flow through a temperate glacier, [by] Krimmel, R. M. Tangborn, W. V. and Meier., M. F. (In [International Hydrological Decade. The role of snow and ice in hydrology. Proceedings of the Banff symposia, September 1972. Paris, UNESCO; Geneva, WMO; Budapest, IASH, p. 401-16 (IAHS-AISH Publication No. 107.))Google Scholar
Stenborg, T. 1969. Studies of the internal drainage of glaciers. Geografiska Annaler. Vol. 51A, Nos. 1-2, p. 13-41.CrossRefGoogle Scholar
You have Access

Send article to Kindle

To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about sending to your Kindle.

Note you can select to send to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

Throughflow water velocities in Austre Okstindbreen, Norway
Available formats
×

Send article to Dropbox

To send this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Dropbox.

Throughflow water velocities in Austre Okstindbreen, Norway
Available formats
×

Send article to Google Drive

To send this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Google Drive.

Throughflow water velocities in Austre Okstindbreen, Norway
Available formats
×
×

Reply to: Submit a response


Your details


Conflicting interests

Do you have any conflicting interests? *