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Show - 1 - A recent report on current avalanche research in Europe ( l) has described and illustrated a chemical method of measuring mean temperatures over long periods in the field. At the time that report was prepared, complete technical details were not available. This information has recently been received from Switzerland, and the present Miscellaneous Report has been prepared to disseminate details to research foresters who may find the method useful, Many aspects of microclimate ( avalanche control, reforestation, timberline ecology, fire conditions) can be studied to best advantage if mean air and soil temperatures are available for many different sites in a given locality. Ordinary methods of instrumentation for collecting mean temperature data, such as thermographs or recording thermometers, are complex and costly when used for simultaneous measurements at many different sites. The chemical method described below utilizes, a small, simple and inexpensive sensing element which permits widespread temperature observations with minimum cost and effort. This method, based on the temperature- dependency of sugar inversion, was first introduced some 20 years ago, but information on it apparently has not received wide distribution. At present the method is being used in the comprehensive study of avalanche prevention, reforestation and timberline ecology being carried out by agencies of the Swiss government on the Stillberg Project near Davos, Switzerland. Fundamentals of the method and its field application are discussed in a paper by Pallman and Frei, ( 2) published in 1943. The pertinent sections of this paper are translated and presented below. A New Principle and Method of Temperature Measurement Until now there have been several proven methods available for temperature measurement: |
