RICO: Gerber scientific (GSI) 1000-hz PVM. Version 1.0

This data set includes airborne measurements obtained from the NSF/NCAR C-130 aircraft during the "Rain in Cumulus Over the Ocean" (RICO) project. This data set contains 1000 hertz PVM data. The files are in netCDF format. Two hot-wire liquid water sensors and a PVM-100 laser-based liquid water sensor were mounted on the C-130 for the program. While all systems performed well, accumulation of salt on the hot-wire elements tended to increase the baseline drift in the raw output. RAF employed a loose-couple processing method to remove the excess drift. Both techniques, hot wire and PVM-100, have a tendency to underestimate the total liquid water in large drops or mixed phase clouds. The effective radius Re of the cloud droplets (XGRFF) is given by Re(um) = 30,000 x XGLWC(g/m^3)/XGSFC(cm^2/m^3). As the values of XGLWC and XGSFC approach zero the noise in the calculated values for Re will approach infinity given Re is the ratio of the two quantities. Thus to get all meaningful values of Re, a conditional statement should be applied to the ratio to avoid excessive noise. The recommended approach is to chose a limiting value of XGLWC below which no value of Re is calculated. With additional care in removing any remaining small offsets in the XGLWC and XGSFC data, the limiting value of XGLWC can be chosen as small as 0.010 g/m^3 for this data set. XGRFF was calculated with an XGLWC threshold of 0.05 and the additional condition that XGSFC>0 to avoid negative radius value.