Milton Mount McKinley Range Expedition, Glaciological Research on the North Fork of the Eldridge Glacier
Milton Mount McKinley Range Expedition
Glaciological Research on the North Fork of the Eldridge Glacier
H. Adams Carter and David L. Atherton
"Science be hanged!" I stated flatly, expressing in one terse sentence the sentiments of the Non-Scientists. The scene: camp on Alaska’s Mount Crillon; the date: mid-July, 1934. However, there was work enough for all. The “silly” Scientists continued to measure the rate that the glacier was pushing down into Crillon Lake and played fourth of July all summer by exploding dynamite to see how thick the ice really was. “As if you couldn’t see that it’s moving fast, with all that ice breaking off into the lake! And what matters is the surface, not the thickness of the ice!” With that we Non-Scientists set out back-packing for the next camp at eleven p.m. in order to make a sizable detour by way of a virgin summit before our return to this camp.
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“No climbing yet!” I stated equally firmly. The scene: camp on the north fork of the Eldridge Glacier, 20 miles east of Mount McKinley; the date: late June, 1960. “We didn’t get those grants§ to make the first ascent of the “Matherhorn.” Besides, that 50° ice slope that leads up to Station Brooks will polish our technique for climbs later.”
Such was the metamorphosis of at least one mountaineer. Here we were, undertaking the kind of field research which twenty-six years before I had scorned. In the intervening years I had come to realize the importance of glaciological research and also the essential part that mountaineering plays in it. The scientific work gives the mountaineer an additional useful purpose. On the other hand, the non-mountaineering scientist simply can not operate safely and successfully in many mountainous regions. It would be hazardous for him to climb to high observation points up precipitous slopes or to cross heavily crevassed glaciers without either a knowledge of climbing techniques or a mountaineer to guide him. All the members of the Milton Mount McKinley Range Expedition, to a greater or lesser extent, combined both scientific and mountaineering interests. We were all anxious to carry out the glaciological program and at the same time we wanted to climb some of the towering peaks about us. Our scientific leader was David Atherton, veteran of Cambridge University glaciological expeditions to Iceland and Greenland. To balance him, our other Englishman, Brian Wilson, had his degree in physics from Oxford. He had come as an exchange master from Clifton College to Milton Academy with the secret resolve to visit the Alaska Range before returning to England. Equally well set off against each other were our undergraduate members, Harvard’s Nat Goodhue and Yale’s Doug Bingham. The latter, our skilled radio operator, was returning with me to the McKinley region for the third time. Tom Bisbee and I, both schoolmasters at Milton Academy, completed the roster.
On June 27 Don Sheldon landed us one by one in his Piper Super Cub at 6500 feet in the upper basin of the Eldridge Glacier not far from our Icefall Camp of 1958. (See A.A.J., 1959, 11:2, pp. 201-7.) Next morning David and I were climbing onto a knife-edged snow ridge above the ice slope to reoccupy Station Brooks. “What a chute down into the icefall that would be,” said David. "And how can you talk about a station on bed rock on the ridge top? The only rock here is where the slope is too steep to hold snow." Perplexed, I scanned the ridge. “It should be right here,” I answered and just at that moment caught sight of a wooden peg emerging an inch above the surface. This top inch of our four-foot survey stake which rose out of the huge cairn on the wind-swept ridge gave us our first proof of how much snow had piled up in this region since we had been there two years before. This had been a rock ridge, but the snowfall during the last two years had greatly exceeded the amount that could melt off it during the short summer. A quick glance at our previous photographic panoramas confirmed our suspicions that the whole snow level on the glacier was appreciably higher. Everywhere rock outcrops had either diminished or disappeared altogether. The peak across the way could now best be climbed without touching rock on what two years before had been a rock ridge.
Except for one day, whenever the weather was even passable for the next three weeks, we worked hard on our glaciological studies. We set up lines of stakes across the glacier and measured its rate and type of flow; we drilled and studied snow cores down to depths of 50 feet; we laboriously dug snow pits to observe the snow and took its specific gravity and temperature; we trekked over 20 miles down the glacier to the junction of the main Eldridge to study an ice-dammed lake; we duplicated dozens of photographs to show changes in icefalls and in snow and ice cover; we investigated wave ogives in icefalls. Much of this involved mountaineering problems, but we fell into none of the gaping crevasses in the icefalls nor plunged down any ice slopes, although I cut my fingers to the bone when a handful of slate came out on a steep rock slope. Anyone who does not avoid the frost-shattered stuff that masquerades as rock in the region needs his head examined. But permanent stations must be on bed rock and you have to climb to them. So much for this aspect, as it is well covered by the glaciological note which follows.
Pure mountaineering as such occupied only three days. On one day, still 1000 feet below the summit of a 9000-foot peak, we beat an ignominious retreat and rappelled back down the ice slope and over the bergschrund when it appeared that a foot of slush, with blue ice beneath it, was ready to avalanche off the steep slopes directly above us. On the other two days we reached our summits. On July 3 we left camp at three a.m., heading for what we had long called the “Matherhorn”; this is the higher of two 11,000-foot peaks that lie east of Mount Mather and are connected to it by a ridge. We wound our way up the basin past enormous crevasses towards Mather’s northeast face. My diary reads as follows: “As we approached what appeared to be an unbroken wall festooned with séracs, the slope increased. Crust gave way to wind-blown powder. Then, as we climbed, the hidden valley between Mather and the “Matherhorn” gradually opened. The peaks above looked as if some giant child had tried to plaster the precipitous walls but lacked the skill to do more than to gob the snow on in colossal ice blocks. The only place that I have ever seen that looks more like the Cordillera Blanca is that range itself. While we crossed swaths of fallen avalanche blocks, we looked anxiously up at others still precariously in place that seemed to hang a thousand feet or more right over our heads.” Snow conditions were ideal as we cramponed up the ever steepening headwall to the col between Mather and our peak. On the far side of the col, the cliffs dropped to a sickening hole, where lay the head of the main Eldridge Glacier. Clouds scudded in and out among the seemingly unclimbable peaks which surrounded it. Above us, our heavily corniced ridge looked short but spectacular. Well out on the hidden valley side and away from the cornice, we made quick work of the remaining 500 feet. Once on top, we had a rude shock. The ridge dropped off for some 750 feet into a wide col or really a plateau from the far side of which rose a second peak, just a few feet higher than where we stood. Though the clouds were piling in thicker and thicker, we headed down the ridge, across the plateau and up the steep face on the far side. As we sat on the summit, the clouds reassuringly opened to let us see that we sat on the highest point. A traverse down a steep face let us descend into the hidden valley.
On July 17 we climbed Peak 9152, 4½ miles northeast of Mather and the last of the major summits on the Muldrow-Eldridge divide between Mount Mather and Anderson Pass to be climbed. (Only a month later the second ascent was made from the Muldrow side as will be seen elsewhere in this Journal.) We approached the mountain up a glacier that heads up in a cirque on its western face, gained the southwestern ridge on the right and climbed on steep but excellent snow in a high, blustery wind. The fleeting clouds continued to play hide and seek, and we wondered whether this was our day. As we neared the summit, the ridge emerged from the mists. Since the ice we had seen gleaming from below was only on the surface, we kicked or cut easily into the firm snow under it. Finally, perched on the summit, a long, slightly corniced ridge, we gloried in the only perfect weather of the day and absorbed a most fantastic panorama. To the east, McKinley rose majestically over the summit of Peak 10,200. Mather dominated our glacier along with the “Mather- horn” and the other 11,000er. Everywhere but in the distant plains to the north lay a maze of steep, jagged, glistening snow spires, except where they were cut by the ribbon-candy stripes of the Muldrow Glacier and the north fork of the Eldridge far below us. We traversed along the far side of the summit and climbed down the northeast ridge and over a second summit before we dropped down a steep slope back to the cirque and to camp.
Our weather was not particularly favorable when viewed as a whole. Clouds and storms prevented any work on nineteen of the thirty-seven days we were in the field. However, we did manage to work on all but seven of the first twenty-five days. It was during the last twelve that it stormed incessantly.
Thus possibly can mountaineers thoroughly enjoy themselves and at the same time, under the guidance of a trained glaciologist, make their little contribution to science. A summary of the glaciological work follows.
H. A. C.
The scientific work of the expedition was, of course, somewhat hampered by poor weather; in particular, higher altitude firn investigations and a short trip to the upper main Eldridge Glacier had to be abandoned. However, despite the uncertainties of the daily gamble as to whether the conditions would clear and hold sufficiently for us to observe if we climbed to our station, we were very lucky in our guesses and were able to make good use of the weather that we actually had.
Meteorological observations were made at our camp at 6500 feet. These results supported the theory that the main accumulation period in this region is during the autumn and that the winter, though cold, produces comparatively little precipitation. Local conditions have an unusually big effect on the weather as was strikingly demonstrated to us one day when we observed above us, clouds at different altitudes travelling in three different directions.
Measurements of firn temperatures were all very close to the freezing point indicating that, despite its location, the glacier was of the temperate alpine type rather than the cold polar type. This was explained as being produced by the small winter precipitation and the winter cold wave being later destroyed by the summer ablation prior to the next accumulation season. This type of summer accumulation pattern is particularly susceptible to small climatic variations which may produce big variations in the annual accumulation by altering the proportions of the precipitation occurring as rain or as snow.
Velocity profiles were observed which gave a maximum velocity of 600 feet per annum. There was considerable slip at the edges of the glacier which is in accordance with the high velocity to width ratio of 1:6.
Examination of firn stratification was difficult on account of the numerous ice bands that are formed during the accumulation period; however, numerous holes were drilled and cores examined. Correlations were obtained and annual layers estimated and these appeared to correlate with the meteorological records for the region. Annual precipitation was found to vary widely with an approximate mean of 20 inches of water. It is suggested that these large variations in precipitation, which have a tendency to form groups of “lean” and “fat” years, might be sufficient to initiate the rapid advance of a potentially unstable glacier.
A wave ogive system, emanating from a cwm glacier by camp, was examined, being of particular interest as it was completely above the firn line. The cwm was fed by avalanche slopes and it is probable that there are considerable seasonal fluctuations in its outflow and that the variations produce the waves which appear to be of the simple annual type.
Comparison of reference photographs with those taken on the reconnaissance expedition showed that in the higher parts of the collecting zone there had been considerable recent increase in the ice and snow coverage. Examination of the glacier itself led to the conclusion that, despite wasting of the lower tributary glaciers, the main north fork was in a comparatively healthy condition. In the case of a high altitude glacier system of this type climatic amelioration accompanied by increased precipitation would generally favour initially an advance of the glacier.
A very interesting investigation was made of an ice-dammed lake near the junction of the north fork of the Eldridge with the main Eldridge glacier. The lake has a system of small raised beaches for 350 feet above its low summer level caused by the periodic filling and emptying of the lake, which is drained by a river alternating between a channel over the ice beside the lateral moraine and a sub glacial tunnel. These provide an indication of the glacial history over the last two hundred years or so and suggest that the glacier is at present not far from its maximum height. Incidentally, the repeated reversion of the river to the sub-glacial tunnel is strong evidence for the tunnel being reformed each time in the same course so that an esker may be in the process of formation beneath the glacier.
The scientific report of the expedition’s field work has been submitted for publication in the Journal of Glaciology.
D. L. A.
Summary of Statistics
Area: North fork of Eldridge Glacier, Alaska Range.
“Matherhorn,” 11,000 feet, July 3, 1960 (whole party)—first ascent. Peak 9152, July 17, 1960 (whole party)—first ascent.
Personnel: H. Adams Carter, leader; David L. Atherton, scientific director; Douglas K. Bingham, Thomas Bisbee, Nathaniel M. Goodhue, Jr., Brian J. Wilson.
§Grants-in-aid were generously provided by the Arthur Gilkey Research Fund of the American Alpine Club, by the Mount Everest Foundation and by the Harvard Travellers Club. Glaciological and surveying instruments were lent by the U. S. Army’s SIPRE and by the American Geographical Society. Our scientific sponsor was the American Alpine Club.