Ice thickness and volume changes across the Southern Alps, New Zealand, from the little ice age to present.

ABSTRACT: Rapid changes observed today in mountain glaciers need to be put into a longer-term context to understand global sea-level contributions, regional climate-glacier systems and local landscape evolution. In this study we determined volume changes for 400 mountain glaciers across the Southern Alps, New Zealand for three time periods; pre-industrial "Little Ice Age (LIA)" to 1978, 1978 to 2009 and 2009 to 2019. At least 60 km³ ± 12 km³ or between 41 and 62% of the LIA total ice volume has been lost. The rate of mass loss has nearly doubled from - 0.4 m w.e year^-1 during 1,600 to 1978 to - 0.7 m w.e year^-1 at present. In comparison Patagonia has lost just 11% of it's LIA volume. Glacier ice in the Southern Alps has become restricted to higher elevations and to large debris-covered ablation tongues terminating in lakes. The accelerating rate of ice loss reflects regional-specific climate conditions and suggests that peak glacial meltwater production is imminent if not already passed, which has profound implications for water resources and riverine habitats.

SUBMITTER: Carrivick JL 

PROVIDER: S-EPMC7415160 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature