Reanalysing the 2007–19 glaciological mass-balance series of Mera Glacier, Nepal, Central Himalaya, using geodetic mass balance

Patrick Wagnon (1) , Fanny Brun (1) , Arbindra Khadka (2) , Etienne Berthier (3) , Dibas Shrestha (2) , Christian Vincent (1) , Yves Arnaud (1) , Delphine Six (1) , Amaury Dehecq (1) , Martin Ménégoz (1) , Vincent Jomelli (4)

1 IGE - Institut des Géosciences de l’Environnement
2 Tribhuvan University
3 LEGOS - Laboratoire d'études en Géophysique et océanographie spatiales
4 CEREGE - Centre européen de recherche et d'enseignement des géosciences de l'environnement

The 2007-19 glaciological mass-balance series of Mera Glacier in the Everest Region, East Nepal, is reanalysed using the geodetic mass balance assessed by differencing two DEMs obtained from Pléiades stereo-images acquired in November 2012 and in October 2018. The glaciological glacier-wide annual mass balance of Mera Glacier has to be systematically decreased by 0.11 m w.e. a −1 to match the geodetic mass balance. We attribute part of the positive bias of the glaciological mass balance to an over-estimation of the accumulation above 5520 m a.s.l., likely due to a measurement network unable to capture its spatial variability. Over the period 2007-19, Mera Glacier has lost mass at a rate of −0.41 ± 0.20 m w.e. a −1 , in general agreement with regional averages for the central Himalaya. We observe a succession of negative mass-balance years since 2013.

Mots clés: Glacier mass balance; glacier monitoring; mountain glaciers

Domaines: Sciences de l'environnement

Patrick Wagnon, Fanny Brun, Arbindra Khadka, Etienne Berthier, Dibas Shrestha, et al.. Reanalysing the 2007–19 glaciological mass-balance series of Mera Glacier, Nepal, Central Himalaya, using geodetic mass balance. Journal of Glaciology, 2021, 67 (261), pp.117-125. ⟨10.1017/jog.2020.88⟩. ⟨hal-03051883⟩