𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Parametrization of the effect of drizzle upon the droplet effective radius in stratocumulus clouds

✍ Scribed by Robert Wood

Publisher
John Wiley and Sons
Year
2000
Tongue
English
Weight
824 KB
Volume
126
Category
Article
ISSN
0035-9009

No coin nor oath required. For personal study only.

✦ Synopsis

Abstract

A method is presented to parametrize the effects of drizzle upon the droplet effective radius in stratocumulus clouds. The cloud‐droplet size distribution in stratocumulus is represented by the sum of a modified Gamma distribution to represent the small (radius <20 μm) droplets and an exponential Marsh all‐Palmer‐type distribution to represent the large (drizzle) droplets. Using this approach a relationship is derived to account for the effect of drizzle upon k, the cube of the ratio between the volume and effective radius. Observational evidence from flights in a range of different air‐mass types is presented to validate the approach. The results suggest that the value of k pertaining to the small droplets is better parametrized as a function of volume radius rather than of droplet concentration. The results also suggest that, as the ratio of liquid‐water content contained in the large droplets to that in the small droplets increases beyond 0.05, the value of it decreases significantly. This results in an underprediction of the effective radius if commonly used parametrizations for k are used.

📜 SIMILAR VOLUMES

A model of the development of droplet ef
A model of the development of droplet effective radius in convective cloud
✍ T. W. Choularton; K. N. Bower 📂 Article 📅 1993 🏛 John Wiley and Sons 🌐 English ⚖ 792 KB

## Abstract A model is presented of a growing cumulus turret which is used to investigate the sensitivity of the droplet effective radius in a convective cloud to variations in the cloud‐base temperature, the liquid‐water content, the vertical wind speed at cloud base, the cloud condensation nucleu

Laboratory studies of the effects of mix
Laboratory studies of the effects of mixing on the evolution of cloud droplet spectra
✍ J. Latham; R. L. Reed 📂 Article 📅 1977 🏛 John Wiley and Sons 🌐 English ⚖ 651 KB

## Abstract Experiments were performed in which a cloud of droplets formed by condensation was drawn slowly down a cylindrical tube of length 5 m. the effect on the spectrum of mixing‐in humidified but undersaturated air was studied. The most striking observation was that the mixing process was hi

The effect of temperature and humidity f
The effect of temperature and humidity fluctuations on the liquid water path of non-precipitating closed-cell stratocumulus clouds
✍ Stephan R. de Roode; Alexander Los 📂 Article 📅 2008 🏛 John Wiley and Sons 🌐 English ⚖ 728 KB

## Abstract The spatial variability of the liquid water path (LWP) is analyzed from a large‐eddy simulation of the diurnal cycle of stratocumulus clouds as observed during FIRE I. In stratocumulus clouds, the temperature and the total specific humidity cannot fluctuate independently, but are tightl

The effect of revised collision efficien
The effect of revised collision efficiencies on the growth of cloud droplets by coalescence
✍ J. T. Bartlett 📂 Article 📅 1970 🏛 John Wiley and Sons 🌐 English ⚖ 378 KB

## Abstract The collection efficiencies of water drops falling in still air have been recalculated by Hocking and Jonas (1970). In this paper these revised values have been used to estimate the rate of production of large droplets (__r__ > 30 μm) by coalescence. It is found that there is an increas