A statistical approach to field measurements of the chemical evolution of cold (<0°C) snow cover

Two statistical methods for the analysis of data on the evolution of the chemical composition of cold snow (<0°C) in the field (Lac Laflamme, Quebec) were compared. The methods used on the data were regression analysis (One sample per sampling date over a long cold period) and ANOVA (replicate samples on a restricted number of sampling dates over shorter periods). The relative power of the tests to determine the detectable amplitude of chemical changes was derived from the theoretical power of the tests under comparable conditions of sampling (number of observations) and from the estimated error variances of the measured data.