31 Models of Clouds, Precipitation and Storms
Part 3. Meteorology and Climatology
Published Online: 15 APR 2006
Copyright © 2005 John Wiley & Sons, Ltd
Encyclopedia of Hydrological Sciences
How to Cite
Flossmann, A. I. 2006. Models of Clouds, Precipitation and Storms. Encyclopedia of Hydrological Sciences. 3:31.
- Published Online: 15 APR 2006
Clouds play an important role for life on earth. Apart from influencing, for example, the radiative balance of the atmosphere and the lifetime of atmospheric trace constituents, they are the essential element in the hydrological cycle. Clouds transport the evaporated water of the oceans to the continents where the precipitation releases the water load. This release of water can be more or less vigorous depending on the energy stored in the cloud in the form of condensed hydrometeors (liquid or solid). This energy depends on the amount of available moisture and the way the vertical lifting necessary for cloud formation proceeds. We distinguish here mainly two different forms with varying extensions on the horizontal scale: the gentle uplift associated to the large-scale lifting, for example at a frontal zone, and the vigorous small-scale ascent associated with convection, knowing that also mixed forms of the lifting occur.
This article provides an introduction to the complex subject of modeling clouds, the production of precipitation, and the development of cloud and storm systems. The elements intervening in cloud modeling are exposed, starting from a description of the physical phenomena. On the basis of the occurring scale problem, a number of approaches for simplification are presented. These simplifications concern the dynamics as well as the microphysics. Bulk and bin modeling approaches are explained, as well as cumulus parameterizations. Some numerical problems are discussed. This approach gives an insight into current state-of-the-art cloud modeling and the necessary balance between the degree of parameterization, the number of physical and chemical processes relevant to a particular problem, and the available computing resources.
- microphysics processes;
- modeling techniques;
- bulk microphysics;
- bin microphysics;
- cumulus parameterization;
- numerical techniques