A prime input variable to uncoupled ice-sheet models, or for estimating the
mass budget of present-day ice sheets, is the distribution of net surface
mass balance. In most eases this is extrapolated from relatively few direct
measurements over a limited time period, and parameterised in terms of
continentality, surface elevation and other broad-scale indicators. Between
1989 and 1995 a series of oversnow traverses around the interior of the
Lambert Glacier basin gathered a comprehensive set of data on snow
accumulation and surface properties, surface climatology, ice-sheet
velocities, elevations and thicknesses. Above the 2000 m level accumulation
averages were found to be 76 kg ma−2a−1
(σ = 74), much lower than at similar elevations in
Wilkes Land. The traverse route contains three distinct accumulation
regimes: a relatively high accumulation zone along the western side despite
higher average elevations, a very low accumulation zone in the south due to
the effect of inereased continentality and an eastern sector that exhibits a
rain-shadow effect in predominantly easterly wind fields. Inter-annual
variability is high- with 1993 a colder year, recording only half the longer
term average accumulation over the portion of the route that was
measured.