Sir,

During the last several decades there has occurred a very noticeable decrease in the flow of the rivers San Juan, Mendoza, Tunuyan, Diamante and Atuel, fed exclusively by snow and ice from the high Cordillera in the Argentine provinces of San Juan and Mendoza. This is a matter of great concern, because these rivers are the only sources of water for the important agriculture of the two provinces.

In order to facilitate a study of the volume decrease of the glaciers on the Argentine side of the high Cordillera between lat. 30° and 36° S., alpinists who have photographed glaciers in this region are kindly requested to send copies with approximate dates, location and other useful information to the Consejo Nacional de Investigaciones Cientificas y Tecnicas, Calle Rivadavia 1917, Buenos Aires, Argentina.

The Consejo would also appreciate receiving information on the possible location in libraries, archives or private collections of older photographs, especially those taken between the turn of the century and 1962, when the whole region was covered by aerial photography.

25 April 1973