Measuring cloud properties from meteorological radiosondes RESUBMITTED

Measuring cloud properties from meteorological radiosondes

K.A. Nicoll1, R.G. Harrison1 and S.Kneifel2

1Department of Meteorology, University of Reading, Reading, UK 2 Department of Atmospheric and Oceanic Sciences, McGill University, Montreal, Canada

Observations of in-situ cloud properties are an essential aspect of cloud microphysics studies. Meteorological balloons and small unmanned aerial vehicles readily provide a platform from which high resolution cloud measurements can be made, both in the vertical and horizontal directions. Currently, however, one limiting factor in the use of these platforms for cloud studies is the lack of availability of lightweight, low power sensors. This work describes a number of small, inexpensive and disposable instruments for cloud detection, which are designed for use alongside conventional meteorological radiosondes such as the Vaisala RS92 radiosonde. Data values from the extra sensors are sent across the existing UHF radio link synchronously with the standard radiosonde data such as temperature, pressure, RH and GPS, using the specially designed PANDORA interface. No extra hardware at the ground station is required. Cloud properties measured with these sensors include solar radiation, visual range, supercooled liquid water content, turbulence and electric charge. This work will described each of these sensors in turn and present data from a number of in-cloud flights demonstrating their operation.