M. J. Bentley, James A. Smith, S. Jamieson, M. Lindeman, B. Rea, A. Humbert, T. Lane, C. Darvill, J. Lloyd, F. Straneo, V. Helm, D. Roberts
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引用次数: 5
Abstract
Abstract. The Northeast Greenland Ice Stream has recently seen significant
change to its floating margins and has been identified as vulnerable to
future climate warming. Inflow of warm Atlantic Intermediate Water (AIW)
from the continental shelf has been observed in the vicinity of the
Nioghalvfjerdsfjorden (79∘ N) Glacier calving front, but AIW
penetration deep into the ice shelf cavity has not been observed directly.
Here, we report temperature and salinity measurements from profiles in an
epishelf lake, which provide the first direct evidence of AIW proximal to
the grounding line of 79∘ N Glacier, over 50 km from the calving
front. We also report evidence for partial un-grounding of the margin of
79∘ N Glacier taking place at the western end of the epishelf
lake. Comparison of our measurements to those close to the calving front
shows that AIW transits the cavity to reach the grounding line within a few
months. The observations provide support for modelling studies that infer
AIW-driven basal melt proximal to the grounding line and demonstrate that
offshore oceanographic changes can be rapidly transmitted throughout the
sub-ice-shelf cavity, with implications for near-future stability of the ice
stream.
期刊介绍:
The Cryosphere (TC) is a not-for-profit international scientific journal dedicated to the publication and discussion of research articles, short communications, and review papers on all aspects of frozen water and ground on Earth and on other planetary bodies.
The main subject areas are the following:
ice sheets and glaciers;
planetary ice bodies;
permafrost and seasonally frozen ground;
seasonal snow cover;
sea ice;
river and lake ice;
remote sensing, numerical modelling, in situ and laboratory studies of the above and including studies of the interaction of the cryosphere with the rest of the climate system.