The Scavenging of Radon Progeny by Snow and Rain
Abstract
In the previous paper Greenfield et al. show that changes in atmospheric gamma radiation rates due to radon progeny adsorbed by rain measured at 6-20 m above ground can be used as a real-time monitor of rain and snow precipitation rates in several locations around the world. In New Zealand, at the Ardmore Field Station operated by the University of Auckland, a gamma ray detection system of the sort described earlier was installed 6 m up a meteorological tower carrying the usual wind speed, wind direction, temperature, humidity and rainfall measuring equipment and attached to a data logger. In addition, a vertically pointing X Band meteorological radar was deployed together with three rain-drop size spectrum measuring devices (disdrometers) at the ground. The microphysical data obtained, particularly from the radar and the disdrometers, allows the construction of a case by case one-dimensional cloud physics model so that the hydrometeor size spectrum, surface area and fall speeds can be depicted in a reasonably realistic way. This then allows modeling of the scavenging processes by the snow and rain in a more quantitative way thus enabling a program of detailed investigation of the microphysical processes involved in the hypothesis presented in the earlier paper: that this mechanism allows gamma ray count rates to be used as a surrogate for rainfall rates. Interesting questions related to the spatial representativeness of various rainfall data sets can also be pursued.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2003
- Bibcode:
- 2003APS..MARH14010A