Decay of a long-term monitored glacier: Careser Glacier (Ortles-Cevedale, European Alps)

摘要

The continuation of valuable, long-term glacierobservation series is threatened by the accelerated mass losswhich currently affects a large portion of so-called “benchmark”glaciers. In this work we present the evolution of theCareser Glacier, from the beginning of systematic observationat the end of the 19th century to its current conditionin 2012. In addition to having one of the longest and richestobservation records among the Italian glaciers, Careser isunique in the Italian Alps for its 46 yr mass balance seriesthat started in 1967. In the present study, variations in thelength, area and volume of the glacier since 1897 are examined,updating and validating the series of direct mass balanceobservations and adding to the mass balance record intothe past using the geodetic method. The glacier is currentlystrongly out of balance and in rapid decay; its average massloss rate over the last 3 decades was 1.5m water equivalentper year, increasing to 2.0m water equivalent per year in thelast decade. Although these rates are not representative at aregional scale, year-to-year variations in mass balance showan unexpected increase in correlation with other glaciers inthe Alps, during the last 3 decades. If mass loss continuesat this pace, the glacier will disappear within a few decades,putting an end to this unique observation series.