different but simultaneous forces twisting the ice beyond its elastic limit. 

 TRACKING: (V.A.)— Following the edge of an ice pack. 

 TRANSECTION GLACIER: (II.A 2.)— Through glacier. 

 TURRET ICE: (I.A.4.f.)— Ropak. 



UNCONFORMITY ICEBERG: (II.A.5.a.)— An iceberg characterized 

 by unconformities below which the ice is of different type from that 

 above. The difference may be very marked, as between blue, water- 

 formed ice and neve, or less marked so as not to be easily distinguishable 

 unless separated by silt-bands. Weathering of this type of iceberg 

 is accelerated by the presence of many crevasses and silt-bands. (Fig. 

 97.) 

 VALLEY GLACIER: (II.A.2.b.)— A stream of land ice that flows toward 

 sea level through definite valleys. See glacier, land ice. (Frontispiece, 

 Figs. 71-74.) 

 VALLEY ICEBERG: (II.A.5.a.) — An iceberg eroded in such a manner 

 that a large U-shaped slot extends through the iceberg with large 

 pinnacles or slabs on either side. Sometimes the slot is awash. These 

 icebergs do not turn over, but sail on as majestically as a well-ballasted 

 ship. Valley icebergs deteriorate chiefly by calving and melting at 

 the water line. When the lightened iceberg rises a series of water 

 lines circling the base is exposed. See iceberg. (Figs. 89, 90.) 

 WALL-SIDED GLACIER: (II.A.2.a.)— A stream of land ice that flows 

 toward sea level unconfined by any marked valley wall. See glacier, 

 land ice. (Fig. 69.) 

 WASH AND STRAIN ICE FOOT: (I.B.l.a.)— An ice loot formed 

 from ice casts and slush and attached to a shelving beach between the 

 high and low water marks. High waves cause the formation to build up 

 above the high water mark later. 

 WASTAGE: (V.C.) — The direct or indirect conversion of ice into water 

 or water vapor. It takes place by evaporation, melting, and calving. 

 WATER OPENING: (I.C.I.)— A break in sea ice that reveals the sea 

 surface. Specific types of water openings are: Crack, lead, polynya, 

 bay, and bight. 



Frequently water openings exist in an ice area with the ice arranged 

 either regularly or haphazardly. No specific term is applied to such 

 water openings. In these cases the concentration of ice is described as 

 scattered, broken, etc., depending upon the ratio of ice to sea surface. 

 WATER SKY: (V.B.) — Dark streaks, patches, or grayness on the under- 

 side of extensive cloud areas due to the absence of reflected light from 

 open water areas. Water sky is darker than land sky. See blink, 

 sky map. (Fig. 43.) 

 WATER SMOKE: (V.B.)— Frost smoke. 

 WEATHERED: (V.B.) — Descriptive of ice that has been destroyed or 



9559340—52—7. 



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