Derivation of an adjustment factor map for the estimation of the water equivalent of snowfall from ruler measurements in Canada

This paper provides an updated fresh snowfall water equivalent adjustment factor (ρswe) map for Canada to allow the estimation of solid precipitation amount from ruler measurements of the depth of freshly fallen snow, which has been the standard method for measuring snowfall since Canadian climate measurements began in the middle of the nineteenth century. The ρswe map is created based on the comparison of corrected solid Nipher gauge precipitation to snowfall ruler depth measurements at 175 stations with more than 20 years of concurrent observations. The Nipher gauge correction process involved a careful analysis of station metadata to obtain precise information on anemometer heights and the dates that Nipher gauges were activated. The updated fresh snowfall water equivalent adjustment factor map allows estimates of ρswe to be obtained for all long‐term climate stations in Canada. The spatial pattern is consistent with processes influencing the density of fresh snowfall and its initial settling ...