ICE FLOW MEASUREMENTS ON FRANZ JOSEF GLACIER NEW ZEALAND IN 1966

Surface ice-flow rates measured between April and September 1966 near the actively advancing snout of the Franz Josef Glacier show considerable variation over area and with time. Over a distance of 500 m, horizontal components range from 189 ± 4 cm/day to 68.1 ± 1.3 cm/day, and vertical components vary between 70.2 ± 2 cm/day downwards and 11.5 ± 0.6 cm/day upwards. The maximum flow rate of 790 ± 150 cm/day was measured during heavy rain in April 1966, but by May 1966 the flow in the same area had dropped to 189 ± 4 cm/day. The estimated quantity of ice discharged through an inferred cross section confirms that the glacier was much more active in 1966 than in 1956 (45,200 m3/day in August 1966, compared with 17,900 m3/day in March 1956). If the present discharge were maintained, the glacier should recover about half the length lost since the present recession began in 1951. A large kinematic wave (velocity 15.4 ± 1 m/day) suggests an abnormally high ice velocity (7.0 ± 0.4 m/day) , in which condition the Franz Josef Glacier appears not to obey the flow-Jaw for ice. © Taylor & Francis Group, LLC.