Showers of small, hard pieces of ice have been crumbling away for an hour, cascading 300 feet down the sheer glacier wall. Rifts at the edge of the weakening section darken. Without warning, the great blue frosted chunk of rim pulls away. It seems to hang suspended while thunder from the crack reverberates in the fjord; then, in slow motion, it slides down the face. Spray explodes out from the base while the top has barely begun its fall, and a great wave sets off toward the opposite bank.
Resonant booming and the hollow clatter of ice mix with the high strident calls of Arctic terns as Hubbard Glacier drops chunk after chunk from its six-mile face into the mouth of the Russell Fjord.
The wave drenches the bank where we ten tourists are standing. We had been kayaking for six days on a trip with Alaska Discovery through Nunatak and Russell Fjords. We traveled with the minimum of technology, and we had no means of contact with the outside world.
Local bush pilot Mike Ivers flew us in, with our two leaders, in a small float plane from Yakutat. Yakutat itself is remote, jutting out into the Atlantic to receive some of Alaska's most ferocious weather. It also lies on a major fault line that has been the scene of recent earthquakes.
Our destination was a narrow beach below the bare, steep-sloping rock on the side of Nunatak Fjord. The beach is actually a toehold of regeneration for the land. A glacier has the greatest erosive impact of any natural force, scouring bedrock with its gritty undersurface and the pressure of its enormous weight.
The scale of the original glacier was plain from the size of the fjord as we set out. From my kayak in the middle of the fjord, I could barely see the others in our party. Those on the edge were minute specks of orange and yellow life jackets, almost lost against the deep blue water.
We were following in the tracks of Nunatak Glacier - now retreated into the separate arms of the East Nunatak and West Nunatak. We camped above West Nunatak - in one of the most beautiful places I have ever seen.
Two days later, at the junction of Nunatak and Russell Fjords, we dozed in the constant Alaskan sun, waiting for the wind to diminish. We waited in vain, eventually setting out Russell, battling the wind and the 15-foot tide that flowed in from the Atlantic.
The joy of kayaking is an integral part of this trip. It is easy to fall into the rhythm of paddling, breaking and swirling the water - sometimes marbled green like the endpaper of an old book, or scattered with small chunks of blue ice.
The passage across the fjord was a grueling, yet satisfying, hour. When we reached land, we saw fresh wolf and bear tracks in the wet sand.
Hubbard Glacier is slowly advancing, narrowing the entrance to the fjord. The tide is forced through at enormous velocity, swirling big icebergs along with it. We were able to paddle to the bank facing Hubbard only by split-second timing, using the 15 minutes of slack tide. Even so, the boats were swept brusquely ashore by the wash of waves from continual calving, the breaking away of glacial ice.
The next day on Osier Island, a tiny knob less than a quarter of a mile from the face, I spent all day on a rocky promontory close to the ice.
Arctic terns posed in the sun before diving into the water at the glacier's base. The water was racing toward high tide, and suddenly I understood why a long stretch was smooth and free of ice. The current was sucking floating ice under the glacier and spitting the pieces out far down the face.
On the side of the knob facing the glacier, I saw a highland meadow and left my niche to climb up to it. The ground was thick with wild strawberries, yellow dryas, salmonberries, magenta fireweed, and the pink bells of wintergreen.
I startled a pair of willow ptarmigans and their chicks. The white feathers of the male against the mottled brown of his head seemed scant reminder of snow and ice and winter.
It is always dangerous to come close to a glacier face. I had spent the day looking at small falls clatter steadily down, isolating one section of the rim. We were an hour away from the island when the whole face slid away in a succession of cannon shots. A wave curled up over the rocks, crashing against the forested knob where I had been sitting, flinging ice and spray high into the meadow.
Alaska's wilderness is not a ''protected environment.'' The knowledge of your guides is critical; we had left before the sun softened the glacier's face enough to make it fall.
There are other spectacular wilderness trips but nowhere else did I see the drama I experienced at Hubbard.
The trip described costs $625, plus $150 air charter from Yakutat. It is not necessary to have had previous kayaking experience; the Kleppers are extremely stable boats, and two full days are devoted to traveling in the quiet of Nunatak Fjord to accustom trip members to the technique.
Alaska Discovery has never had a serious client injury, despite the fact that it specializes in bringing people into direct contact with wilderness.
For further information, contact Alaska Discovery, PO Box 26-CM, Gustavus, Alaska 99826. Telephone (907) 697-3431.