Chemical Temperature Integration

Abstract

The sugar-inversion method (Pallmann method) of deriving mean temperatures related the reaction velocity of sucrose hydrolysis to temperature by means of an Arrhenius-type equation. The method was tested for precision, accuracy and adaptability to climatological networks. Twenty-milliliter glass ampoules filled with a clear sucrose solution were used as temperature sensors. The sensors were virtually unaffected by shortwave radiation. Precision of the method for half-month periods in forested terrain was ±0.02C. Absolute accuracy of the method was severely affected by the nonlinearity of sensor response; this was circumvented by use of empirical corrections based on the temperature mean and amplitude. At five standard climate stations, arithmetic mean temperatures for half-month periods (1967?1968) were predicted with an average error of 0.37?0.64C in summer (over mean temperatures of 30 to 10C) and 0.86?1.05C in winter (over mean temperatures of 10 to ?10C). The Pallmann method of temperature integration is simple and economical. With the addition of 150 gm liter?1 sodium chloride to the sucrose solution, the method is usable in all seasons.