Ablation of ice-cored moraine in a humid, maritime climate : Fox Glacier, New Zealand

Auteur(s) et Affiliation(s)



Description :
To evaluate the effects of varying debris-cover and climate on ice-melt in a maritime mid-latitude setting, an 11-day ablation stake study was undertaken on ice-cored moraine at Fox Glacier. Ablation rates varied with enhancement of melt-rate under thin debris-covers. Air temperature from nearby Franz Josef Glacier allowed for a simple degree-day approach to ablation calculations, with regression relationships indicating air temperature is the key climatic control on melt. Digital elevation models produced from topographic surveys of the ice-cored moraine over the following months indicated that ablation rates progressively decreased over time, probably due to melt-out of englacial debris increasing debris-cover thickness. The morphology of the sandur appears to be strongly determined by episodic high-magnitude fluvial flows (jökulhlaups), in conjunction with surface melt. Thus, hummocky moraine appears to be a transient landform in this climatic setting.


Type de document :
Article de périodique

Source :
Geografiska annaler. Series A. Physical geography, issn : 0435-3676, 2012, vol. 94, n°. 3, p. 339-349, nombre de pages : 11, Références bibliographiques : 2 p.

Date :
2012

Editeur :
Pays édition : Suede, Stockholm, Svenska sällskapet för antropologi och geografi