| Summary: | An assessment of the glaciological and meteorological characteristics of Dome A, the summit of the East Antarctic ice sheet, is made based on field investigations during the austral summer of 2004/05. Knowledge of these characteristics is critical for future international studies such as deep ice-core drilling. The assessment shows that: (1) Dome A is characterized by a very low 10 m depth firn temperature, ?58.3°C (nearly 3°C lower than at EPICA Dome C and 1°C lower than at Vostok). (2) Automatic weather station (AWS) measurements of snow surface height and reference layers in a snow pit indicate the present-day snow accumulation rate at Dome A is within the range 1?3 cm w.e.a?1. Densification models suggest a range of 1?2 cm w.e.a?1. This is lower than at other sites along the ice divide of East Antarctica (IDEA). Annual layers at Dome A are thus potentially thinner than at other sites, so that a longer record is preserved in a given ice thickness. (3) The average wind speed observed at Dome A (<4 m s?1) is lower than at other sites along IDEA. Together, these parameters, combined with radio-echo sounding data and information on the subglacial drainage distribution beneath Dome A, suggest Dome A as a candidate site for obtaining the oldest ice core. journal article
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