Glacier Studies in Alaska, 1957
Glacier Studies in Alaska, 1957
Melvin G. Marcus*
UNTIL recent years, glacier studies by
American scientists have been concentrated in the Southeastern Alaska region. Members of the American Alpine Club have followed these activities with some interest and many members have participated in research projects. In the past decade, there has been a shift of public and scientific interest to the more remote polar glaciers of Greenland and Antarctica. This has been particularly true during the current International Geophysical Year. The investigation of temperate alpine and piedmont glaciers remains, however, an important and vital phase of this international program.†
As in the past, considerable attention is being concentrated on the numerous glaciers in Southeastern Alaska. A fairly continuous program of glacier studies has been maintained in this area and some records date as early as the late 19th Century. Present studies, therefore, bring earlier records up to date and provide a continuity of observation that may eventually yield a greater knowledge of the nature and behavior of glaciers. Also, expeditions are attracted to the region because of its accessibility. A large number of glaciers, many investigated in the past, are easily reached by boat. Field personnel need only leave their craft for short periods of time in order to photograph and measure the glacier fronts. Glaciers and ice fields associated with the more recent projects are usually only a short hop by ski- or floatplane from major Alaskan cities.
Four field parties studied glaciers in Alaska in 1957. Although the activities of these groups were widely divergent, nevertheless they all sought greater understanding of glaciers and their physical and biological environments. The differences in immediate objectives, however, necessitate a separate discussion of each project.
This project has as its primary objective the preparation of large scale (1:5000 and/or 1:10,000) maps of nine selected Alaskan glaciers. Glacial surfaces and valley bottoms will be mapped at a contour interval of two meters. In some instances it will be possible to plot one-meter contour intervals for more accurate portrayal of glacial features. Since air photo- grammetric methods are being supplemented by ground photogrammetry, the results should be extremely precise and accurate. It is expected that this precision will be particularly valuable if future studies are effected on the same glaciers. Later mapping of similar quality will, for example, provide means by which changes in glacial mass and configuration may be accurately computed.
This is the first time that Alaskan glaciers have been mapped at a large scale. Although nine glaciers were selected, only three were surveyed in
These were Worthington Glacier near Thompson Pass, Polychrome Glacier in Mt. McKinley National Park, and West Gulkana Glacier in the Delta River area. Work was partially completed in the Nizina region of the Skolai Mountains and on Salmona Glacier of the Kenai Peninsula. Selection of the remaining glaciers is tentative; but size, location, and accessibility will influence the final decisions. At least one more summer will be required to complete the field work. Meanwhile, field data is being plotted at the Institute of Geodesy, Photogrammetry, and Cartography at Ohio State University by James B. Case. The final maps will be drafted at the American Geographical Society.
Juneau Ice Field Research Project
The Juneau Ice Field Research Project completed its ninth year of glacio- logical and related studies during 1957. Research for the fourth consecutive year was carried out mainly on Lemon Creek Glacier, one of the stations in the North American Glaciology Program of the International Geophysical Year. Studies were conducted during two observation periods, the first lasting from 5 to 17 June and the second from 1 to 16 September. A total of six men participated. The Jamesway Hut research station at the head of the glacier was again occupied and a ski-wheel Super Piper Cruiser assisted in transporting equipment and personnel to and from the campsite.
The project’s four main objectives were to (1) determine the hydro- logical budget of Lemon Creek Glacier; (2) determine the three dimensional field of motion over the glacier surface; (3) reconstruct the variations in size of the glacier during the last several centuries; and (4) maintain the photographic record of the margins and firn lines of the Lemon Creek and related glaciers. The latter included photographic coverage of the Lemon Creek, Mendenhall, Herbert, Eagle, Gilkey, Norris, Taku, Hole- in-the-Wall, and East and West Twin glaciers. In addition, U. S. Navy aircraft photographed Lemon Creek Glacier for purposes of mapping. A final map of the glacier will be drafted at Ohio State University this year.
It is believed that the 1957 field party set some sort of record for operational efficiency on a project of this type. All of the rather imposing list of objectives were accomplished during the relatively short, split field-season. There was, in fact, sufficient time remaining to enlarge upon the scheduled program. Since such complete success is uncommon, it is worth mentioning some of the contributing causes. A long stretch of clear weather in June undoubtedly increased field effectiveness, but this was balanced in September when only four days were considered adequate for normal field operation. It was possible during periods of bad weather, however, to pursue phases of research that did not require unobstructed visibility. The usual risks of glacial travel under low visibility conditions were greatly reduced by familiarity with the terrain, frequent use of trail markers, and the fact that it was never necessary to travel more than a few miles from camp. Furthermore, the existence of a nearby dry hut offers greater inducement to storm travel than does a waterlogged tent-camp. The presence of the hut and the small size of the party (never more than four men in the field) also reduced the logistical problems that so frequently plague scientific as well as mountaineering projects of this type. Finally, it should be noted that all of the personnel were competent mountaineers and no time was lost in training. Since the project was operating under optimum conditions, bom of eight years experience in the same area and a wealth of equipment, it seems unlikely that such success can be easily duplicated in an unfamiliar region. The experience does, however, indicate once again some of the advantages inherent in a small, well-trained party following a carefully planned program.
The final year of the Juneau Ice Field Research Project is planned for
A full summer field season is expected and the current sequence of observations on the various glaciers will be completed. In addition, a Juneau to Skagway traverse of the Ice Field is planned for the purpose of gathering ecological, glaciological, and geological information.
Project 4.2 is a reconnaissance survey of numerous accessible glaciers in Southeastern Alaska, particularly those that have been studied previously. In 1957, the field party of seven examined 15 glaciers (Portage, Oxyria, Raven, Spencer, Bartlett, Trail, Black Rapids, Cantwell, Castner, Gulkana, Muldrow, Tazlina, Kennecott, Worthington, and Valdez) during the last days of June, the month of July, and early August. Travel was by automobile or aircraft. From August 13 until September 5, studies were made of the glaciers in Prince William Sound, the party operating from the limit purse-seiner Valiant Maid out of Cordova. This latter investigation was the principal goal of the summer’s activities and followed up the work of the Harriman Expedition in the late 1890’s, the surveys of Grant and Higgins, of the Geologic Survey, and of Tarr and Martin in the early 1900’s, and the expeditions of William O. Field in 1931 and 1935. In addition, a new set of aerial photographs were obtained from the United States Navy to supplement earlier vertical and oblique photographs taken in 1941, 1951, and 1954.
Principal methods of investigation and documentation were survey mapping, record photography, and botanical dating. Surveying was accomplished using a Wild T-12 Pocket Theodolite. Stations were established at prominent rock positions around the terminus. Horizontal and vertical angles were then determined between these stations as well as from the stations to prominent points on the glacier. The triangulation network thus established provided the base for a roughly accurate map of current features. These maps, when drawn to completion, are useful for plotting additional data, locating stations, and comparing existing conditions of the terminus with those evidenced by older or future maps. Photographic documentation was accomplished by taking pictures in panoramic series from permanent stations, usually the same ones occupied for survey mapping. The resultant photographs may be compared to others of a different date to detect changes in terrain and vegetation as well as in the glacier.
Botanical dating was used to establish the dates of previous glacier advances. This is normally accomplished by coring or sectioning certain trees, counting the annual rings to determine their age, and then adding a corrective figure for the time required for the tree to become established. Trees on recessional or terminal moraines are usually selected for dating since they normally indicate a period of glacial stability, whereas the less pronounced topography of the inter-moraine outwash reflects poorly defined stages of recession.
The project will continue through the International Geophysical Year, but the program will not be as ambitious as in 1957. Next summer, the 4.2 group will probably investigate glaciers in the Juneau, Glacier Bay, Skagway and Yakutat areas. When the final surveys are completed and the data is processed, it is quite likely that Project 4.2 will have produced the most extensive and comprehensive record of Alaskan glaciation to date.
The primary purpose of Project 4.17 is to make a detailed study of McCall Glacier in the Brooks Range of Alaska. Particular emphasis is being placed on the study of the glacier’s micro-climate with the aim of developing correlations with the Arctic Ice Pack. Research on the polar McCall Glacier should also provide some interesting comparisons with the temperate Blue Glacier in the Olympic Mountains which is also being investigated in detail (Projects 4.1 and 4.3). Although operations were suspended after the death of Richard Hubley, Senior Scientist on the project, it is expected that a four-man party will return to the glacier this spring.
* The writer wishes to express his thanks to Charles C. Morrison and Calvin J. Heusser for their help in providing information for this article.
† See "Glacier Studies During the International Geophysical Year,” by Richard C. Hubley, A.A.J., 1957, vol. 10, No. 2 (Issue 31).