Glacier melt, air temperature, and energy balance in different climates: The Bolivian Tropics, the French Alps, and northern Sweden

International audience This study investigates the physical basis of temperature-index models for three glaciers in contrasting climates: Zongo (16°S, 5050 m, Bolivian Tropics), St Sorlin (45°N, 2760 m, French Alps), and Storglaciären (67°N, 1370 m, northern Sweden). The daily energy fluxes were com...

Full description

Bibliographic Details
Published in:Journal of Geophysical Research
Main Authors: Sicart, Jean-Emmanuel, Hock, Regine, Six, Delphine
Other Authors: Glaciers et ressources en eau d'altitude - Indicateurs climatiques et environnementaux (GREATICE), Geophysical Institute Fairbanks, University of Alaska Fairbanks (UAF), Department of Earth Sciences Uppsala, Uppsala University, Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), ANR-05-JCJC-0135,TAG,Relation climat-glacier : flux turbulents et processus d'interactions dynamiques entre l'atmopshère et le climat(2005)
Format: Article in Journal/Newspaper
Language:English
Published: HAL CCSD 2008
Subjects:
Online Access:https://insu.hal.science/insu-00381076
https://insu.hal.science/insu-00381076/document
https://insu.hal.science/insu-00381076/file/2008JD010406.pdf
https://doi.org/10.1029/2008JD010406
Description
Summary:International audience This study investigates the physical basis of temperature-index models for three glaciers in contrasting climates: Zongo (16°S, 5050 m, Bolivian Tropics), St Sorlin (45°N, 2760 m, French Alps), and Storglaciären (67°N, 1370 m, northern Sweden). The daily energy fluxes were computed during melt seasons and correlated with each other and with air temperature on and outside the glacier. The relative contribution of each flux to the correlations between temperature and melt energy was assessed. At Zongo, net short-wave radiation controls the variability of the energy balance and is poorly correlated to temperature. On tropical glaciers, temperature remains low and varies little, melt energy is poorly correlated to temperature, and degree-day models are not appropriate to simulate daily melting. At the yearly scale, the temperature is better correlated to the mass balance because it integrates the ablation and the accumulation processes over a long time period. At Sorlin, the turbulent sensible heat flux is greater because of higher temperatures, but melt variability is still controlled by short-wave radiation. Temperature correlates well with melt energy mainly through short-wave radiation, probably because of diurnal advection of warm air from the valley. At Storglaciären, high correlations between temperature and melt energy result from substantial variability of the sensible and latent heat fluxes (which both supply energy to the glacier), and their good correlations with temperature. In the three climates, long-wave irradiance is the main source of energy, but its variability is small and poorly correlated to the temperature mainly because cloud emissions dominate its variability.