Response times of ice-sheet surface heights to changes in the rate of Antarctic firn compaction caused by accumulation and temperature variations

摘要: Variations in accumulation rate A s(t) and temperature T at the surface of firn cause changes compaction (FC) height H(t) that do not involve mass, therefore need to be accounted for deriving mass from measured H(t). As effects propagate into firn, FC is affected with a highly variable complex response time. The during measurement periods depend on history prior measurements. Consequently, knowledge times climate perturbations important estimate required length time series used models. We use our numerical model, which time-dependent both rate, examine rates change dH(t)/dt variations using sample data selected sites Antarctica. Our results show dH(t)/dt, are particular interest, much shorter than responses Typical several years <20 years. faster warmer higher-accumulation areas such as Byrd Station, West Antarctica (4 years), slower colder lower-accumulation Vostok, East (18 years). (0.9 year 2.2 Vostok), but corresponding persist longer. associated density significantly preserved density–depth profiles. For typical fluctuations weather, satellite observations since 1982 meteorological 1979 essentially sufficient correct measurements beginning 1992.