Geography Reference
In-Depth Information
As part of the IPY, a multi-national team investigated the geological history of the mountain
range. One of the key findings is that the ice sheets covering the mountains are growing at
the base, whereby widespread re-freezing contributes to the consolidation of the base of the
ice sheet. As one of the scientists, Robin Bell of Columbia University, remarked:
Water has always been known to be important to ice sheet dynamics, but mostly as a
lubricant. As ice sheets change, we want to predict how they will change. Our results show
that models [attempting to understand the future trajectory of ice-sheet stability] must
include water [and its potential role] beneath.
Sub-glacial water, far from being marginal, holds the key to better understanding ice-sheet
dynamics, especially when then linked to debates about the impact of global warming on the
Antarctic and future sea level change.
The freezing and re-freezing of sub-glacial water not only contributes to ice-sheet dynamics
and their modelling but also initially confused researchers who were puzzled by the
existence of a series of re-frozen structures underneath the ice sheet - no one believed that
water moving underneath a great mass of ice sheet could fundamentally alter its structure.
As water was being melted and re-frozen, under the ice sheet, it was being transported uphill
towards mountain ridges where the ice sheet was thinner. On re-freezing, new structures
were being fashioned at the base of the ice sheet - creating what were termed 'ghostly
mountains'. Consequently, older ice is pushed to the surface of the ice sheet, thus making it
more accessible for scientists to access evidence of past climates.
The role of re-freezing will continue to be a major area of future research in both the
Antarctic and Greenland ice sheets. The distribution of water under the ice sheet is now
understood to be absolutely critical to understanding ice-sheet dynamics and whether it will
be easier to predict future decay or not. This was not the case even a decade ago.
2. Million Year Plus Ice Core Project (MY+)
While the 'Million Year Plus Ice Core Project' sounds like a marketing gimmick, it actually
highlights something rather important about what we understand about the earth's oldest ice.
It is emblematic of the work of the International Partnerships in Ice Core Sciences (IPICS),
which is a group of scientists from over 20 countries with an active interest in the topic.
Four priority projects, including this one, have been identified, with the aim of trying to
retrieve ice over 1-1.5 million years old from the East Antarctic plateau in particular.
