Roll forward, Franz Josef, you magnetic river of ice

Press, 28 September 1988, Page 22

Roll forward, Franz Josef, you magnetic river of ice

The present advance of the Franz Josef and Fox glaciers may help to boost the West Coast’s sagging tourist trade. TRISH McCORMACK reports.

Peter McCormack, a veteran Franz Josef guide, has been recording the glacier’s ebb and flow since the 19505. The 1980 s have seen his predictions of a glacial advance come true. He and his wife, Elizabeth, have been taking photographs of the local advance. Since 1983 the Franz Josef Glacier has advanced more than half a kilometre. It had slipped back further than ever before in the 19705. Westland National Park measurements, made regularly, indicate that the glacier pushed forward as rapidly as two metres a day during a peak period in 1984. This winter, there has been a steady advance of two to three metres a month. Both Franz Josef and Fox glaciers are now flowing over alluvial gravels, which has prob-

ably sped their rate of advance. During past advances, they flowed along bedrock and pushed alluvial gravels or moraine in front of them. The glacier valleys are undergoing dynamic change. Successive visits show a landscape that is altered almost day by day. It is more than 100 years since the first records were made in the glacier region. In 1872, Prime Minister William Fox made a perilous horseback journey through rivers and round coastal bluffs. He did some fine paintings of glacier country. Westland explorers Charles Douglas and A. P. Harper com-

pleted the first Franz Josef Glacier survey in the 1890 s. The first tourist excursions to the glaciers were made in the 1900 s. Tracks and bridges were built, and a spectacular gallery was built around rock walls on the true right of the valley. The end of the century’s first decade saw a significant advance of ice moving relentlessly towards the gallery. Despite attempts to hack and even blast the ice away, the gallery was completely destroyed. The glacier flowed round one side of Sentinel Rock, which is some two kilometres down valley from the present glacier

terminal. In 1913 Defiance Hut was built on the true left of the glacier, allowing tourists to spend a night in the mountains. Unfortunately, a period of substantial glacial retreat followed. The glacier shrunk, causing ancient moraine — on which the hut was sited — to subside. The hut was resited on solid rock, but further glacier shrinkage made it almost impossible to reach it. By the mid-19305, the glacier had advanced again. It regained about half of its volume lost between 1893 and 1920. A further retreat was recorded

between 1934 and 1946; a lake formed on the western side of the valley. This was countered by an advance of 400 metres between 1946 and 1951. The advancing ice bulldozed moraine in front, and filled the lake. The glacier then retreated substantially between 1951 and 1965. Glacier enthusiasts tend to regard retreat with disappointment and advance with enthusiasm. They were greatly excited over the spectacular 1965-67 advance: the glacier gained an extra 375 metres and regained about 20 per cent of the volume that had been lost since 1909. A new tourist hotel was being built to give views of the glacier, but as it neared completion the glacier had slipped out of sight. Then, just before the hotel was opened, the glacier reappeared. It seemed to give its blessing to this new tourist enterprise. It also gave the new Franz Josef Hotel a flying start as it attracted publicity. The road was completed over ’ the Haast Pass, which further enhanced tourism. But the glacier again began to retreat, falling back further than ever. A glacier advances when heavy snowfalls on its neve, or upper snowfield, allow a growth in ice that exceeds ice lost through melting. The story of glacier access is just as dynamic as that of advance and retreat. The glacial lake formed during the 1930 s retreat effectively blocked access and a rowboat had to be used. This operation ended when an iceberg shot up dramatically from the lake bottom, nearly swamping the boat. A high track was then made round the rock face — on the true left of the valley, winding its way above the Trident waterfall. In the 1970 s it became impossible to reach the glacier from this side. An impressive engineering feat was accomplished with the building of Fletcher Bridge over a short but spectacular gorge which gave access via the glacier’s true right. In 1981 it became impractical to get on to the glacier from the bottom. Local people led a campaign to establish a heli-hike operation, with a helicopter landing point part way up the glacier on Luncheon Rock. A hut was built there, in a place chosen as

a safe building site, well out of the way of possible glacial advance. The large rock area had not been touched by the 1960 s advance. When the heli-hike operation started, it was necessary to climb some distance from the hut site down to the glacier. But from 1983, the glacier began a steady climb up to hut level and eventually towered above it. The

hut was cut in half so it could be moved to a safer position. However, the glacier moved first. A two-tonne block of ice knocked half of the hut a. distance of some 25 metres. It was comparatively undamaged, and the relocation was completed. But the glacier had not finished its work, and went on to completely cover Luncheon Rock. The hut had to be flown out. ,

Peter McCormack is confident that the latest advance is not over, and could continue for several years. Although there has been little snow on the low hills, there have been big snow buildups in the glacier neves and cold summers. Even the Fletcher Bridge, once a half-hour walk from the glacier terminal, could be threatened by advancing ice.