Articles | Volume 11, issue 1
Research article
22 Jan 2018
Research article |  | 22 Jan 2018

Hotplate precipitation gauge calibrations and field measurements

Nicholas Zelasko, Adam Wettlaufer, Bujidmaa Borkhuu, Matthew Burkhart, Leah S. Campbell, W. James Steenburgh, and Jefferson R. Snider

Abstract. First introduced in 2003, approximately 70 Yankee Environmental Systems (YES) hotplate precipitation gauges have been purchased by researchers and operational meteorologists. A version of the YES hotplate is described in Rasmussen et al. (2011; R11). Presented here is testing of a newer version of the hotplate; this device is equipped with longwave and shortwave radiation sensors. Hotplate surface temperature, coefficients describing natural and forced convective sensible energy transfer, and radiative properties (longwave emissivity and shortwave reflectance) are reported for two of the new-version YES hotplates. These parameters are applied in a new algorithm and are used to derive liquid-equivalent accumulations (snowfall and rainfall), and these accumulations are compared to values derived by the internal algorithm used in the YES hotplates (hotplate-derived accumulations). In contrast with R11, the new algorithm accounts for radiative terms in a hotplate's energy budget, applies an energy conversion factor which does not differ from a theoretical energy conversion factor, and applies a surface area that is correct for the YES hotplate. Radiative effects are shown to be relatively unimportant for the precipitation events analyzed. In addition, this work documents a 10 % difference between the hotplate-derived and new-algorithm-derived accumulations. This difference seems consistent with R11's application of a hotplate surface area that deviates from the actual surface area of the YES hotplate and with R11's recommendation for an energy conversion factor that differs from that calculated using thermodynamic theory.

Short summary
The hotplate precipitation gauge has the potential to solve some problems with conventional precipitation gauge measurements, especially for snowfall. This paper extends the seminal published work, Rasmussen et al. (2011). We assert that the precipitation rate algorithm we have developed for the hotplate is an improvement on that which was previously published.