New cloud physics instrumentation requirements

The Air Force requirements for in situ cloud physics measurements are reviewed, and areas of instrumentation deficiency are pointed out. One area is in the melting zone, where present instrumentation fails to provide adequate total ice/water content values. Presently, two research instruments - the TWCI and EWER - designed to obtain total ice/water mass directly are being test flown. Another area is the measurement of particles in thin cirrus clouds, where the particle numbers are generally smaller than foreseen in the requirements, and particle sizes are not adequately sampled. A major area also is the measurement of very large particles of clusters in the melting and snow regions to determine upper cutoff values for size spectra.