scholarly journals The Existence of Multiple Steady States in the Flow of Large Ice Masses

1980 ◽  
Vol 25 (91) ◽  
pp. 183-184 ◽  
Author(s):  
A. C. Fowler

AbstractWe discuss the possibility of the occurrence of thermal instability in ice sheets and glaciers. This may arise from the non-linear viscous heating term, which could provide for the existence of multiple steady states in the flow and temperature fields: a word of warning is given about the applicability of these ideas.

1980 ◽  
Vol 25 (91) ◽  
pp. 183-184 ◽  
Author(s):  
A. C. Fowler

AbstractWe discuss the possibility of the occurrence of thermal instability in ice sheets and glaciers. This may arise from the non-linear viscous heating term, which could provide for the existence of multiple steady states in the flow and temperature fields: a word of warning is given about the applicability of these ideas.


1986 ◽  
Vol 8 ◽  
pp. 141-145 ◽  
Author(s):  
K.C. Partington ◽  
C.G. Rapley

Satellite-borne, radar altimeters have already demonstrated an ability to produce high-precision, topographic maps of the ice sheets. Seasat operated in a tracking mode, designed for use over oceans, but successfully tracked much of the flatter regions of the ice sheet to ± 72° latitude. ERS-1 will extend coverage to ± 82° latitude and will be equipped with an ocean mode similar to that of Seasat and an ice mode designed to permit tracking of the steeper, peripheral regions. The ocean mode will be used over the flatter regions, because of its greater precision.Altimeter performance over the ice sheets has been investigated through a study of Seasat tracking behaviour and the use of an altimeter performance simulator, with a view to assessing the likely performance of ERS-1 and the design of improved tracking systems. Analysis of Seasat data shows that lock was frequently lost, as a result of possessing a non-linear height error signal over the width of the range window. Having lost lock, the tracker frequently failed to transfer rapidly and effectively to track mode. Use of the altimeter performance simulator confirms many of the findings from Seasat data and it is being used to facilitate data interpretation and mapping, through the modelling of waveform sequence.


2012 ◽  
Vol 17 (6) ◽  
pp. 1227-1251 ◽  
Author(s):  
Eric W. Bond ◽  
Kazumichi Iwasa ◽  
Kazuo Nishimura

We extend the dynamic Heckscher–Ohlin model in Bond et al. [Economic Theory(48, 171–204, 2011)] and show that if the labor-intensive good is inferior, then there may exist multiple steady states in autarky and poverty traps can arise. Poverty traps for the world economy, in the form of Pareto-dominated steady states, are also shown to exist. We show that the opening of trade can have the effect of pulling the initially poorer country out of a poverty trap, with both countries having steady state capital stocks exceeding the autarky level. However, trade can also pull an initially richer country into a poverty trap. These possibilities are a sharp contrast with dynamic Heckscher–Ohlin models with normality in consumption, where the country with the larger (smaller) capital stock than the other will reach a steady state where the level of welfare is higher (lower) than in the autarkic steady state.


Sign in / Sign up

Export Citation Format

Share Document