title: Glacier Melting Increases the Solute Concentrations of Himalayan Glacial Lakes.
abstract: Over the past two decades, we observed a substantial rise in ionic content that was mainly determined by the sulfate concentration at 20 remote high elevation lakes located in central southern Himalaya. At LCN9, which was monitored on an annual basis for the last 20 years, the sulfate concentrations increased over 4-fold. Among the main causes, we exclude a change in the composition of wet atmospheric deposition, as well as a possible influence of decrease in seasonal snow cover duration, which could have exposed larger basin surfaces to alteration processes. Glacier retreat likely was the main factor responsible for the observed increase of sulfate concentrations. We attribute this chemical changes mainly to the sulfide oxidation processes that occur in subglacial environments. Moreover, we observe that the weakened monsoon of the past two decades has only partially contributed to the lakes enrichment through runoff waters that are more concentrated in solutes or lowering the water table, resulting in more rock exposed to air and enhanced mineral oxidation.
authors.affiliation: CNR-Water Research Institute (IRSA), Via del Mulino 19, Brugherio (MB) 20861, Italy.|Ev-K2-CNR Committee, Via San Bernardino, 145, Bergamo 24126, Italy.
authors.forename: Franco
authors.initials: F
authors.lastname: Salerno
authors.affiliation: CNR-Institute of Ecosystem Study (ISE), Largo Tonolli 50, Verbania Pallanza (VB) 28922, Italy.
authors.forename: Michela
authors.initials: M
authors.lastname: Rogora
authors.affiliation: CNR-Water Research Institute (IRSA), Via del Mulino 19, Brugherio (MB) 20861, Italy.
authors.forename: Raffaella
authors.initials: R
authors.lastname: Balestrini
authors.affiliation: CNR-Institute of Ecosystem Study (ISE), Largo Tonolli 50, Verbania Pallanza (VB) 28922, Italy.|Ev-K2-CNR Committee, Via San Bernardino, 145, Bergamo 24126, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Lami
authors.affiliation: CNR-Institute of Ecosystem Study (ISE), Largo Tonolli 50, Verbania Pallanza (VB) 28922, Italy.
authors.forename: Gabriele A
authors.initials: GA
authors.lastname: Tartari
authors.affiliation: CNR-Water Research Institute (IRSA), Via del Mulino 19, Brugherio (MB) 20861, Italy.
authors.forename: Sudeep
authors.initials: S
authors.lastname: Thakuri
authors.affiliation: CNR IRPI-Geohazard Monitoring Group, Strada delle Cacce, 73, 10135 Torino, Italy.
authors.forename: Danilo
authors.initials: D
authors.lastname: Godone
authors.affiliation: Università di Torino , DISAFA and NatRisk, Largo Paolo Braccini 2, 10095, Grugliasco (TO), Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Freppaz
authors.affiliation: CNR-Water Research Institute (IRSA), Via del Mulino 19, Brugherio (MB) 20861, Italy.|Ev-K2-CNR Committee, Via San Bernardino, 145, Bergamo 24126, Italy.
authors.forename: Gianni
authors.initials: G
authors.lastname: Tartari
mesh_terms: D046448:Ice Cover / Q000737:chemistry*; D060106:Lakes; D012914:Snow / Q000737:chemistry; D013431:Sulfates
chemical_list: D013431:Sulfates