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J Ollrnal o/Glaciology, Vol. 6, No. 45, 1966 SYMPOSIUM ON GLACIER MAPPING OTTAW A, CANA D A, 20 -2 2 SEPTEMBER 1 965 THE Sympos ium on Gl acier Mapping, wh ich was h e ld in Ottawa, Canada, on 20- 22 September 1965, was sponsored jointly by the S ub- Committee on Gl ac iers of the National R esearch Council and the Commi ss ion of Snow and Ice of th e In ternationa l Association of Scientific Hydrology. Dr. G. Hatt ersley-Smith a nd hi s Canadian coll eag ues were r espons ible for the l oca l organization and they are to be co ngratulat ed on their fruitful efforts. The proceedings of the Symposium, including the di scu ss ion, wh ich was recorded, are to be published as a specia l iss ue of the Canadian Journal of Earth Sciences. Some 90 peop le attended; half were from Canada, a fair proportion from the United States, and the rest from Engl and, Germany, France, Peru, Swi tzer l and and the U.S.S.R. Many disciplin es such as cartography, photog ramme tr y, geo logy, geography, gl acio logy, geophysics, hydrology and re mot e sensing were re presented and they led to useful and instructi ve discuss ions. Th e parti cipants were welcomed by Dr. Howlett, Dir ecto r of the Di visi on of App li ed Ph ys ics of the National Research Counc il. Dr. Ma rk Me icr, as one of the Vice -P residents of th e Commiss ion of Snow a nd Ice, gave the open ing a ddr ess, illus trat ed the probl ems of glacier mapping by his own expe rienc es and dr ew special at t en tion to mod e rn re mot e sensing t echniques. Thi s address, the following paper by Dr. Va lter Schy tt on the purpose of glacier mapping a nd the next c ritical yet constructive pap er by Dr. T.]. Bl ac hut and Dr. Fritz MU ll er estab lished the gene ral pa tt ern s of thou ght for th e r est of the Sympos ium. Di scu ss ions following these t hr ee prese nt at ions mad e it cl ear that there were t hr ee lignes deforce- a group pr essing for in ventory type of mapping in relation to the programme of the In ternationa l Hydrologi cal Decade, a noth er int erested mainly in th e d eta il ed techni ca l prob lems of mapping, and ano th er concerned wi th pr ese nting every kind of glac iol og ica l data in the greatest detai l on maps. All groups agreed, h owever, that the cartog rapher and the glac iologist n eede d to co-operate much mor e closely in the futur e in order to appr ec iate each ot he r' s problems in produc ing satisfactory maps . O ver 20 papers were presented in three days an d there was ade quate t im e for discussion after eac h pr ese ntation. Cont inuing wit h the fir st day 's proceed ings, Dr. M. G. Marcus and Mi ss Kar en Ewing (Un iversity of Mi chi gan ) dr ew pa rticular attent ion to the problems of symboliz at ion on glacier maps , probl ems th at were enco unt er ed by Fr itz MU ll er and Peter Kasser in their o utstan din g maps of the Axel H eiberg an d Aletsc h glaciers a nd which ar ise whenever maps are used for storing a nd displaying r esea rch data at r egu lar intervals of time in all field sciences. They re mind ed us, as Co lonel Helk did later, that th e pr incipal purpose of a map was to re-cr eate selectively the landscape, or to give a picture of the su rf ace. Th ey a lso dr ew attent ion to the growing use of comp ut e r- cont rolled plotting m ac hines and th e like lihood that mu ch of the g rowin g volume of quant itative informati on wou ld never leave the mac hin es as maps but re main stored as code d symbols on tapes. Colonel Helk of D ans k Geod<etisk In st itut spoke of th e formidable task hi s sma ll cou ntry faced in compiling an acc ura te map of Greenl and and its ice cap to serve as a basis f or gl ac iological measur ements. T he no rth ern third of the island was st ill imprecisely mapp ed. The mere 25 lin es which expe ditions h ad drawn across th e ice with tr eme ndous efforts were on ly very thin thr eads in a vast desert, from which he wo uld hat e to make a map , and mor eover he warned us against drawing conclusions abo ut th e ice on such weak foundation s. H e was clearly sympath etic to glaciol ogica l i nterests, but awa it ed the da y, not too distant , wh en modern au tomated tech niques were suffici en tly developed to ease his task. Professor R. Chevallier presented a fa ct ual pa per pr e pared by the Frenc h Institut Geograp hie National on the series of thr ee aerial ph otographi c maps of th e Mont Blanc mass if, made to a scale of I : 10 ,000 in 1939, 1952 and 1958. Obs er vat ions on sno ut positions of severa l glaciers, on ch anges in surface elevation and on th e velocities of th e Me r de Glace deduced from ogive movement were given. Ing. W. Ki ck (West Germa ny), follo wing in the fo otst eps of the F in sterwa ld er s, gave us a b ea utifully illu strated talk of hi s pr act ical experiences in ma pping the long-te rm va riations of glaciers in th e Himalaya and in Norway by terrestrial photogrammetry. W e were pleased to see the successive maps prin ted of the Ch ogo Lun gma Glac ier a nd of Tun sb ergda lsb re. o less th an five old st ud ents were present of the Fi nsterwa ld er schoo l, which h ad pion eered terrestria l photogr amme tr y of glac iers, two of them, D6rr er and Rein wa rth , being on th eir way to 45 1

SYMPOSIUM O N GLACIER MAPPING OTTAWA, CANAD A, … · J Ollrnal o/Glaciology, Vol. 6, No. 45, 1966 SYMPOSIUM O N GLACIER MAPPING OTTAWA, CANAD A, 20-22 SEPTEMBER 1965 THE Symposium

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Page 1: SYMPOSIUM O N GLACIER MAPPING OTTAWA, CANAD A, … · J Ollrnal o/Glaciology, Vol. 6, No. 45, 1966 SYMPOSIUM O N GLACIER MAPPING OTTAWA, CANAD A, 20-22 SEPTEMBER 1965 THE Symposium

J Ollrnal o/Glaciology, Vol. 6, No. 45, 1966

SYMPOSIUM O N GLACIER MAPPING OTTAW A, CANA D A, 20 -2 2 SEPTEMBER 1965

THE Symposium on G lacier Mapping, which was h eld in Ottawa, Canada, on 20- 22 September 1965, was sponsored jointly by the Sub-Committee on Glaciers of the National R esearch Council and the Commission of Snow and Ice of the International Association of Scientific H ydrology. Dr. G. Hattersley-Smith and his Canadian colleagues were responsible for the local organization and they are to be congratulated on their fru itfu l efforts. The proceedings of the Symposium, including the discussion, which was recorded, are to be published as a special issue of th e Canadian Journal of Earth Sciences.

Some 90 people attended; half were from Canada, a fair proportion from the United States, and the r est from England, Germany, France, Peru, Switzerland and the U.S.S.R. Many disciplines such as car tography, photogrammetry, geology, geography, glaciology, geophysics, hydrology and remote sensing were represen ted and they led to useful and instructive discussions.

The participants were welcomed by Dr. Howlett, Director of the Division of Applied Phys ics of the National R esearch Council. Dr. Mark Meicr, as one of the Vice-Presidents of the Commission of Snow a nd Ice, gave the open ing address, illustrated the problems of glacier mapping by his own experiences and drew special atten tion to modern r emote sensing tech n iques. This address, the foll owing paper by Dr. Valter Schytt on the purpose of g lacier mapping a nd the next critical yet constructive paper by Dr. T . ] . Blachut and Dr. Fritz MUller es tablished the genera l patterns of thought for the rest of the Symposium. Discussions following these three presentat ions made it clear that there were three lignes deforce- a group pressing for inventory type of mapping in rela tion to the programme of the In ternational Hydrological Decad e, a nother interested mainly in the d etailed technical problems of mapping, and another concerned with presenting every kind of glaciological data in the g reatest detail on maps. All groups agreed, however, that the cartographer and the g lacio logist needed to co-opera te much more closely in the future in order to apprecia te each other's problems in producing satisfactory maps .

O ver 20 papers were presented in three days and there was adequate t ime for discussion after each presentation.

Continuing with the first day 's proceed ings, Dr. M. G. Marcus and Miss Karen Ewing (University of Michigan) drew pa rticular attention to the problem s o f symbolization on glacier maps, problems that were encountered by Fritz MU ller and Peter Kasser in their outstanding maps of the Axel H eiberg and Aletsch glaciers a nd which ar ise whenever maps a re used for storing and displaying research data at regula r intervals of time in all field sciences. They reminded us, as Colonel H elk did later, that the principal purpose of a map was to re-create selectively the landscape, or to g ive a picture of the surface. T hey a lso drew attention to the growing use of computer-controlled plotting m achines and the likelihood that much of the growing volume of quantitative information would never leave the machines as maps b ut remain stored as coded symbols on tapes.

Colonel Helk of D ansk Geod<etisk Institut spoke of the formidabl e task his small cou ntry faced in compiling an accura te map of Greenland and its ice cap to serve as a basis for glaciological measurem ents. T he northern third of the island was still imprecisely mapped. T he mere 25 lines which expeditions had drawn across the ice with tremendous efforts were on ly very thin threads in a vast desert, from which he would hate to m ake a map, and moreover he warned us against drawing conclusions about the ice on such weak foundations. H e was clearly sympathetic to glaciological interests, but awaited the day, not too distant, when modern a u tomated techniques were sufficiently developed to ease his task.

Professor R. Chevallier presented a factual paper prepared by the French Institut Geographie National on the series of three aerial p hotographi c maps of the Mont Blanc massif, made to a scale of I : 10,000 in 1939, 1952 a nd 1958. Observations on snou t positions of several glaciers, on changes in surface elevation and on the velocities of the Mer de G lace deduced from ogive movement were g iven.

Ing. W. Kick (W est Germany), foll owing in the foo tsteps of th e Finsterwalders, gave us a beautifully illustrated talk of his p ractical experiences in mapping the long-term variations of glaciers in the Hima laya and in Norway by terrestria l photogrammetry. W e were pleased to see the successive maps printed of the Chogo Lungma Glacier and of Tunsbergdalsb re.

o less than five old students were present of the F insterwalder school, which had pioneered terrestrial photogrammetry of glaciers, two of them, D6rrer and Reinwarth, being on their way to

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452 JOURNAL OF GLACIOLOGY

Antarctica with the U.S. expedition. At the close of the meeting it was agreed that if possible the Proceedings should be d edicated to the memory of the late Richard Finsterwalder.

Another ofR. Finsterwalder's old students, Dr. G. Konecny (New Brunswick University) presented his experiences with photogrammetric and electronic surveys of the Athabaska, Saskatchewan, Per Ardua and Otto-Fjord (Ellesmere Island) Glaciers, of the Ward Hunt Ice Shelf, of parts of several Alaskan glaciers and of Mount K ennedy. He clearly had a large fund of recent experiences with terrestrial and aerial photogrammetry and of the use of electronic surveying instruments under a variety of conditions. He drew special attention to the high and variable cost of existing glacier maps and of the need to use the most economical m ethods in order to complete the great task that lies ahead.

Unfortunately, on account of the Allelein glacier incident in Switzerland which Professor R. Haefeli d escribed to us, Peter Kasser could not be present to open the meeting on the second day. His paper with Hans Rothlisberger on their problems in preparing the recent map of the Aletschgletscher was presented by Fritz Muller, who had been closely associated with the field work. H e stressed the great difficulties and expense they encountered in establishing and maintaining on foot the artificial glacier markers for the aerial survey. Dr. 0strem later told us how h e had overcome this problem during the mapping of Josterdalsbre by dropping hundreds of paper packets of powdered ochre from small low­flying aircraft immediately ahead of the photographic plane. His success seemed to be the result of careful planning and a share of good luck with the weather.

The Aletsch mapping again brought out the difficulties of defining precisely a glacier boundary when it is confused with dead ice, moraine or fresh snow. This problem n eeds an arbitrary decision with international agreement.

Mark Meier (U.S . Geological Survey) related some of the interpretations that could be made from his re-mapping of the South Cascade, Nisqually and Klawatti Glaciers. R eaders will already know some of this important work from publications in the Journal. H e drew attention to the problems of attaining sufficient accuracy in elevations from vertical aerial photographs of steep glaciers and to the orthophoto map. The latter is an interesting development in photogrammetric technique which he thought was of considerable value in glacier mapping. The map is virtually a large photograph, accurately rectified, and produced by a machine that automatically eliminates the effects of relief and camera tilt .

William O . Field (American Geographical Society) gave an illustrated summary of his extensive series of records of the variations of glacier termini in southern Alaska, which have been carried out at frequent intervals by simple and inexpensive ground surveys and photographs since 193 I. He emphasized the need to co-ordinate this type of work and to document the records for future use.

G. Petrie and R. J. Price (Glasgow University) were interested in the use of photogrammetry for both glaciological and geomorphological purposes and presented their experiences in using topo­graphical plotting equipment of second-order accuracy in mapping the changes in the Casement Glacier and its surroundings in Alaska from photographs taken in [948 and [962 with very little ground control. A fortuitous pattern of sea inlets provided level control. In their view, periodic surveys of a large number of glaciers can only be accomplished in a r easonable time and economically by using the topographical plotting machines which are much more widely available than the high precision machines that some photogrammetrists consider necessary for glacier mapping.

Mr. Doudin from the Soviet Embassy presented the paper by his Russian colleagues, Professor Avsyuk, Dr. Vinogradov and Miss Kravtsova, which gave a survey of the extent of the glacier mapping programme in their country. Three types of maps are being pursued. On the general topographical maps at scales ranging from I: 25,000 to I : [00,000 conventional glacier symbols are steadily being introduced and it has been necessary to get co-operation with glaciologists to obtain correct interpreta­tion of the field data. The most recent maps of this type cover the T'ien-shan, the polar Urals, EI'brus and the coastal belt of East Antarctica. Special glaciological maps are being produced in association with field research and will cover Zemlya Frantsa-Iosifa and EI'brus. These maps apparently include all kinds of glaciological data and from their description seem to be more comprehensive than those produced so far in other countries. In the case of EI'brus and the Antarctic special atlases are being compiled.

It was a great pity that no Soviet maps were included in the display of glaciological maps arranged at the Symposium, but we certainly look forward to seeing them as soon as they becom e available.

Professor A. J . Brandenburger gave a brief account of the extensive programme of glacier surveying carried out by Ohio State University. It included maps of many Alaskan glaciers, several in the western

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SYMPOS I UM O N GLACIER MAPPING, OTTAWA, CANADA 453

United States and the Ice Field Ranges, Yukon T erritory. Aerial photogrammetric measurements of ice motion on Byrd G lacier and on a line between " Byrd" station and th e Whitmore Mountains in Antarctica were also reported . Both of the latter projects involve aerial triangulation and stand ard errors of ± 3 m . and ± 5 m. respectively were claimed. The maximum speed of Byrd Glacier proved to be 2· 3 m. per day. The second measurement from "Byrd" station is to be made this season.

Professor R. Haefeli (Switzerland) opened the third day's meeting by recalling the various maps that had been prepared of the Unteraargletscher since 1842 and interpreting several features of its behaviour. He also had some interes ting deductions about the ogives and the ice motion of the Aletschgletscher following its recent deta iled mapping.

Professor R. P. Goldthwait (Ohio State University) then gave an account of a re-survey of the ice cliff in Nunatarssuaq (North Greenland) and a reinterpretation of its behaviour.

Dr. A. O. Poulin (U.S. Cold R egions R esearch and Engineering Laboratory) and Mr. T. A . Harwood (Defence Research Board, Ottawa) showed us some fascinating comparisons between conventional aerial photographs and infrared thermal imagery of Arctic ice features such as frozen lakes and the Ward Hunt Ice Shelf. The potential value was clearly demonstrated of therma l views taken in the dark for estimating surface temperatures of ice and snow masses, thickness of ice over water and possibly hidden crevasses.

Mr. A. H. Waite (U.S. Army E lectronics Laboratory) d escribed the recent developments and astonishing achievem ents in radio sounding of ice thicknesses. He reported reflections from cold ice as thick as 3,000 metres and seemed confident that the thickest ice in the world could be sounded with little modification. Plans to carry out rapid aerial radar surveys of surface and bottom ice contours in Greenland and later in Antarctica were announced.

An even more enterprising proposal was made by Dr. Gordon Robin (Scott Polar R esearch Institute) . He wanted to put a radio altimeter in a satellite on a polar orbit to obtain an a ltitude m ap of the surface and the bottom of the Antarctic ice sheet and claimed that the cost would be a fraction of that of any other survey method . The economics of the alternative projects in the Antarctic n eed serious and unbiased consideration before either project is mounted.

During the early stages of the Symposium at the sugges tion of the meeting, a small ad hoc committee was formed to crystallize the needs and implications of the discussions. The committee consisted of Dr. M. F. Meier, Dr. V. Schytt, Dr. F . MUller, Dr. G. H a ttersley-Smith a nd the writer. They drafted a series of resolutions, which, after amendment, were fin a lly adopted at the closing seSSIOn. These resolutions are given below.

W . H. WARD Secretary, Commission of Snow a nd I ce

R esolutions adopted b y the Symposium on Glacier Mapping of the I UGG-IASH Commission on Snow and Ice, 20-22 September 1965.

The Symposium on G lacier Mapping, sponsored by the IUGG-IASH Commission on Snow and Ice, in Ottawa, 20-22 September 1965, adopted the following resolu tions, and requests the Commission to take appropria te further action to implement these resolutions.

I. The Symposium recognizes the value of the resolution, adopted by the Council for the IHD, on a World Inventory of Perennial and Annual Snow and I ce M asses. T he Symposium recommends that the Commission urge UNESCO to encourage the member states to support glacier mapping activities that a re an integral and necessary part of this IHD programme, and recommends that these mapping activities include: (a) small-scale maps, showing the distribution of glaciers, from which total glacier areas can be determined ; (b) larger-scale contour maps of as m any glaciers as possible in representative areas drawn with sufficient accuracy for valid comparisons of mass changes, at intervals of about ten years. For a ll maps, the date, means of survey, and accuracy should be specified, and glaciers should be included with (but differentiated from) other masses of snow and ice which persist for more tha n one year.

2. The Symposium strongly emphasizes the need for d etailed, large-scale glaciological maps of representative glaciers, including their complete drainage basins, particularly for the purposes of the study of the glacier-climate rela tionship as part of the IHD programme, and as a necessary background for many other scientific a nd technological programmes associated with glaciers. A scale I: 10,000 or larger is desirable.

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454 JOURNAL OF GLACIOLOGY

3. Considering the importance in some areas of glaciers as water resources, as elements of attraction or danger to mankind, and as elements in the natural environment, the Symposium recognizes the great need for proper delineation of glaciers on maps of standard topographical series, and urges government agencies responsible for topographical surveys and international organizations such as UNESCO to pay special attention to the continually changing forms of glaciers and the proper distinction between glaciers and ephemeral or persistent snow masses.

4. The Symposium recommends tha t the Commission consider the formation of a Committee on Glacier Mapping to have a continuing responsibility to inves tigate, promote the study of, and report on new techniques for glacier mapping and other ways to record and present spatically distributed glaciological information. This Committee should work in liaison with other groups in similar fields .

5. The Symposium calls to the attention of the Commission the need for (a) a manual on glacier mapping ; (b) a standardization of symbols on glacier maps; (c) preparation of recommendations for international exchange of glaciological maps and data, especially those relating to international programmes such as the IHD.

6. The Symposium on Glacier Mapping requests the Subcommittee on Glaciers, National Research Council of Canada, to explore means of giving suitable recognition to Sebastian and Richard Finster­walder in the Proceedings of the Symposium.

7. The Symposium recognizes the great value of bringing photogrammetrists, cartographers, glaciologists, and other interested persons together for these discussions, and expresses its gratitude to the National R esearch Council of Canada and to the Organizing Committee .