ICE RAMPART: (III.) — An irregular ridge on a sloping shore formed 

 by lake ice pushing a portion of the marginal material to a higher 

 level. See lake ice. 



ICE RIND: (I.A.3.b.)— Ice crust. 



ICE RIVER: (I I. A.)— Glacier. 



ICE RUN: (IV.) — The initial stage in the breakup of river ice. A weak 

 section of ice floats free of its anchorage and releases the water stored 

 above it. This extra water floats the next section free, releasing more 

 stored water. All at once the whole river begins to move, the apparently 

 solid cakes crumbling into brash as they strike the bank and against each 

 other. A few ice cakes from shaded locations are still hard and strong. 

 Armed with gravel and boulders frozen into their bottoms, they crash 

 on bridge piers and grind wooden structures to matchsticks. However, 

 the greater part of the ice disintegrates into rotten ice that melts while 

 one watches it. The next day the river is running clear from bank to 

 bank, with only a solitary ice cake lodged here and there on a sand 

 bar. Breakup on rivers. usually occurs 3 or 4 weeks after the mean air 

 temperature has risen above 32 °F. Cf. debacle, 



ICE SHEET: (II.A.l.a.) — Any large area of continuous ice overlying a 

 land surface. See continental ice. 



ICE SPICULE: (I.A.3., II., III., IV., or V.B.)— A needle-like ice crystal. 



ICE STORM: (V.B.) — A storm in which falling rain freezes as soon as 

 it touches any object (Figure 108) . 



ICE STREAM: 



(1) (II.A.)— Glacier. 



(2) (I.A.l.f.)— Belt. 



(3) (II.A.) — Ice tongue. 



ICE TABLE: (V.C.)— A mass of level ice. 

 ICE TONGUE: 



(1) (II.A.3.b.) — The extension of a valley glacier from the catchment 

 basin to the terminus, i.e., the whole body of the glacier (Frontis- 

 piece). 



(2) (II.A.l.d.) — A steep, narrow cliff of ice, rising high above glacial 

 neve and extending upward toward the higher mountain peaks. 



ICE TONGUE AFLOAT: (II.A.3.b.)— Extensions of the ice of glaciers 

 that persist so far out to sea that their ends are afloat. An ice tongue 

 afloat is perhaps the most striking of all the antarctic land ice forms. 

 There is only one good example in the arctic. 



The characteristics of the ice tongue afloat are, first and foremost, 

 the long sub-triangular shape, and second, a contour very gently convex 

 from side to side and shelving gradually from the shore towards the 

 sea end until the free floating portion is reached, when the upper surface 

 becomes a horizontal plane. Crevasses are usually few at the seaward 



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