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Abstract. We show a method for determining stratus cloud liquid water profiles using a microwave radiometer and cloud radar. This method is independent of the radar calibration and the cloud-droplet size distribution provided that the sixth moment of the size distribution can be related to the square of the third moment. We have calculated these moments with a wide variety of in situ measurements and show that this is a reasonable assumption. Examples of droplet distributions that meet this requirement are the lognormal and gamma distributions. Frisch et al.[1995] retrieved a constant-with-height drop number concentration as well as an effective radius profile; then, using the assumption of a lognormal function, liquid water profiles were derived. We will show here that (1) the retrieval of liquid water profiles does not require a lognormal droplet distribution and (2) the accuracy of the liquid water profile retrieval is independent of radar calibration errors, provided we can relate the sixth moment to the third moment of the distribution through a power law. Thus this paper presents a generalization of the earlier method of Frisch et al. [1995]. MethodThe liquid water for a droplet distribution is given by

A laser ceilometer, an acoustic sounder, and a microwave radiometer were used to estimate cloud thickness and the adiabatic and integrated liquid water content of shallow stratocumulus clouds continuously for three days using two‐minute averages. Although the observed liquid water path was close to the theoretical adiabatic value for most of the three days, there was one four‐hour period when the liquid water content dropped to about 50% of the adiabatic value. Hourly‐averaged values for a 19‐day period of intensive observations show that the cloud water content was generally close to the adiabatic value. Occasionally there were clouds greater than 300 m in depth in which the water content was clearly less than adiabatic.

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