A CHEAP, QUICK AND SAFE WAY OF SURVEYING GLACIERS

The use of a 35 mm or similar camera set up over a theodolite is descr ibed for surveying mountain and polar glaciers where conditions do not allow for extensive detailed surveying or the use of heavy phototheod olites. Though used initially by Spender and Wright in the 1930s on Mo unt Everest and in Greenland and Arctic Canada, but apparently not by others since then, it was again tried our by Wright in Iceland in 1999 . Modern analytical techniques have shown that heights accurate to wit hin 2 m can be obtained from these photographs at distances up to 5 km . In addition, five times as many points can be identified and interse cted in the laboratory from the photographs as was possible using sket ches in difficult field conditions. Some reasons are suggested for the lack of use of this technique by others. The potential of existing su rvey photographs taken in Arctic Canada for large scale surveys of hig h polar glaciers in 1938 is described with the hope that glaciologists and photogrammetrists might undertake their analysis.