A century reconstruction of the mass balance of Glacier de Sarennes, French Alps

AbstractThe 50 year time series of mass balance on Glacier de Sarennes is one of the longest in the French Alps, and so is often used as a reference for glacier variations in the French Alps. Meteorological data can be used to extend the series backwards in time. Martin (1978) proposed such a reconstruction for the 1882–1977 period. With 50 years of observations, we show that the classical method used by Martin is too dependent on the calibration period. We therefore try to improve the accuracy of this reconstruction using the Vincent and Vallon (1997) method which takes into account the albedo change of the surface during the ablation period (this is called the daily method). This new method appears to be stable in time. Once calibrated, the daily method is applied to reconstruct the 1881–1949 period. The new reconstruction is compared to a volumetric balance between two maps from 1906 and 1981. It appears that both reconstructions (classical and daily) fail to render the trend correctly over a long period of time. The cumulative centred mass balance correlates well (r2 = 0.62) with the hydrological mass-balance series of Aletschgletscher, Switzerland.

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Relative performance of empirical and physical models in assessing the seasonal and annual glacier surface mass balance of Saint-Sorlin Glacier (French Alps)

The Cryosphere ◽

10.5194/tc-12-1367-2018 ◽

2018 ◽

Vol 12 (4) ◽

pp. 1367-1386 ◽

Cited By ~ 8

Author(s):

Marion Réveillet ◽

Delphine Six ◽

Christian Vincent ◽

Antoine Rabatel ◽

Marie Dumont ◽

...

Keyword(s):

Energy Balance ◽

Mass Balance ◽

Meteorological Data ◽

Model Performance ◽

Surface Mass Balance ◽

Glacier Surface ◽

Meteorological Forcing ◽

Surface Mass ◽

French Alps

Abstract. This study focuses on simulations of the seasonal and annual surface mass balance (SMB) of Saint-Sorlin Glacier (French Alps) for the period 1996–2015 using the detailed SURFEX/ISBA-Crocus snowpack model. The model is forced by SAFRAN meteorological reanalysis data, adjusted with automatic weather station (AWS) measurements to ensure that simulations of all the energy balance components, in particular turbulent fluxes, are accurately represented with respect to the measured energy balance. Results indicate good model performance for the simulation of summer SMB when using meteorological forcing adjusted with in situ measurements. Model performance however strongly decreases without in situ meteorological measurements. The sensitivity of the model to meteorological forcing indicates a strong sensitivity to wind speed, higher than the sensitivity to ice albedo. Compared to an empirical approach, the model exhibited better performance for simulations of snow and firn melting in the accumulation area and similar performance in the ablation area when forced with meteorological data adjusted with nearby AWS measurements. When such measurements were not available close to the glacier, the empirical model performed better. Our results suggest that simulations of the evolution of future mass balance using an energy balance model require very accurate meteorological data. Given the uncertainties in the temporal evolution of the relevant meteorological variables and glacier surface properties in the future, empirical approaches based on temperature and precipitation could be more appropriate for simulations of glaciers in the future.

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Climatic drivers of seasonal glacier mass balances: an analysis of 6 decades at Glacier de Sarennes (French Alps)

The Cryosphere Discussions ◽

10.5194/tcd-6-2115-2012 ◽

2012 ◽

Vol 6 (3) ◽

pp. 2115-2160

Author(s):

E. Thibert ◽

N. Eckert ◽

C. Vincent

Keyword(s):

Mass Balance ◽

Meteorological Data ◽

Late Winter ◽

Equilibrium Line Altitude ◽

French Alps ◽

Ice Melt ◽

Air Temperatures ◽

Climatic Drivers ◽

Main Component ◽

Snow And Ice

Abstract. Refined temporal signals are extracted from a glacier winter and summer mass balance series recorded at Glacier de Sarennes (French Alps) using variance decomposition. They are related to local and synoptic meteorological data in terms of interannual variability and structured trends. The winter balance has increased by +23% since 1976 due to more precipitation in early and late winter. The summer balance has decreased since 1982 due to a 43% increase in snow and ice melt. A 24-day lengthening of the ablation period – mainly due to longer ice ablation – is the main component in the overall increase in ablation. In addition, the last 25 yr have seen increases in ablation rates of 14 and 10% for snow and ice respectively. A simple degree-day analysis can account for both the snow/ice melt rate rise and the lengthening of the ablation period as a function of higher air temperatures. From the same analysis, the equilibrium line altitude of this 45° North latitude south-facing glacier has sensitivity to temperature of +93 m °C−1 around its mean elevation of 3100 m a.s.l. over 6 decades. The sensitivity of summer balance to temperature is −0.62 m w.e. yr−1 °C−1 for a typical 125-day long ablation season. Finally, the time structure of winter and summer mass balance terms are connected to NAO anomalies. Best correlations are obtained with winter NAO anomalies. However, they strongly depend on how the NAO signal is smoothed, so that the link between mass-balance seasonal terms and NAO signal remains tenuous and hard to interpret.

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Climatic drivers of seasonal glacier mass balances: an analysis of 6 decades at Glacier de Sarennes (French Alps)

The Cryosphere ◽

10.5194/tc-7-47-2013 ◽

2013 ◽

Vol 7 (1) ◽

pp. 47-66 ◽

Cited By ~ 38

Author(s):

E. Thibert ◽

N. Eckert ◽

C. Vincent

Keyword(s):

Mass Balance ◽

Large Scale ◽

Meteorological Data ◽

Low Frequency ◽

Late Winter ◽

Equilibrium Line Altitude ◽

French Alps ◽

Ice Melt ◽

Main Component ◽

Snow And Ice

Abstract. Refined temporal signals extracted from a winter and summer mass balance series recorded at Glacier de Sarennes (French Alps) using variance decomposition are related to local meteorological data and large-scale North Atlantic Oscillation (NAO) anomalies in terms of interannual variability, trends of the low-frequency signals, and breaks in the time series. The winter balance has increased by &plus;23% since 1976 due to more precipitation in early and late winter. The summer balance has decreased since 1982 due to a 43% increase in snow and ice melt. A 24-day lengthening of the ablation period – mainly due to longer ice ablation – is the main component in the overall increase in ablation. In addition, the last 25 yr have seen increases in ablation rates of 14 and 10% for snow and ice, respectively. A simple degree-day analysis can account for both the snow/ice melt rate rise and the lengthening of the ablation period as a function of higher air temperatures. From the same analysis, the equilibrium-line altitude of this 45° N latitude south-facing glacier has a sensitivity to temperature of &plus;93 m °C−1 around its mean elevation of 3100 m a.s.l. over 6 decades. The sensitivity of summer balance to temperature is −0.62 m w.e. yr−1 °C−1 for a typical 125-day-long ablation season. Finally, the correlation of winter and summer mass balance terms with NAO anomalies is investigated. Singularly, highest values are obtained between winter NAO anomalies and summer balance. Winter NAO anomalies and winter balance and precipitation are almost disconnected. However, these results strongly depend on how the NAO signal is smoothed, so that the link between Sarennes mass balance seasonal terms and NAO signal remains tenuous and hard to interpret.

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Glacier mass balance determination by remote sensing in the French Alps: progress and limitation for time series monitoring

IGARSS 2003. 2003 IEEE International Geoscience and Remote Sensing Symposium. Proceedings (IEEE Cat. No.03CH37477) ◽

10.1109/igarss.2003.1294523 ◽

2004 ◽

Cited By ~ 2

Author(s):

J.-P. Dedieu ◽

A. Rabatel ◽

C. Vincent ◽

F. Valla ◽

E. Thibert ◽

...

Keyword(s):

Remote Sensing ◽

Time Series ◽

Mass Balance ◽

Glacier Mass Balance ◽

French Alps

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25 years (1981–2005) of equilibrium-line altitude and mass-balance reconstruction on Glacier Blanc, French Alps, using remote-sensing methods and meteorological data

Journal of Glaciology ◽

10.3189/002214308784886063 ◽

2008 ◽

Vol 54 (185) ◽

pp. 307-314 ◽

Cited By ~ 51

Author(s):

Antoine Rabatel ◽

Jean-Pierre Dedieu ◽

Emmanuel Thibert ◽

Anne Letréguilly ◽

Christian Vincent

Keyword(s):

Remote Sensing ◽

Mass Balance ◽

Satellite Images ◽

Meteorological Data ◽

Equilibrium Line ◽

Surface Mass Balance ◽

Mass Balances ◽

Equilibrium Line Altitude ◽

Surface Mass ◽

French Alps

AbstractAnnual equilibrium-line altitude (ELA) and surface mass balance of Glacier Blanc, Ecrins region, French Alps, were reconstructed from a 25 year time series of satellite images (1981–2005). The remote-sensing method used was based on identification of the snowline, which is easy to discern on optical satellite images taken at the end of the ablation season. In addition, surface mass balances at the ELA were reconstructed for the same period using meteorological data from three nearby weather stations. A comparison of the two types of series reveals a correlation of r > 0.67 at the 0.01 level of significance. Furthermore, the surface mass balances obtained from remote-sensing data are consistent with those obtained from field measurements on five other French glaciers (r = 0.76, p < 0.01). Also consistent for Glacier Blanc is the total mass loss (10.8 m w.e.) over the studied period. However, the surface mass balances obtained with the remote-sensing method show lower interannual variability. Given that the remote-sensing method is based on changes in the ELA, this difference probably results from the lower sensitivity of the surface mass balance to climate parameters at the ELA.

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