30 Topographic Effects on Precipitation
Part 3. Meteorology and Climatology
Published Online: 15 APR 2006
Copyright © 2005 John Wiley & Sons, Ltd
Encyclopedia of Hydrological Sciences
How to Cite
Austin, G. L. and Dirks, K. N. 2006. Topographic Effects on Precipitation. Encyclopedia of Hydrological Sciences. 3:30.
- Published Online: 15 APR 2006
Topography and orography can drastically alter the wind patterns in the atmosphere that in turn can have a major effect on the geographical distribution of precipitation. The processes involved include the upslope enhancement of existing rainfall or the triggering of new rainfall in mountainous regions, and the effect of temperature or humidity contrasts between boundary layer air masses over land and oceanic areas. These processes can result in rainfall patterns ranging from a single triggered thunderstorm to widespread torrential rainfall, as occur when tropical cyclone air masses are pushed up steep coastal mountain ranges. Since the magnitude and distribution of the resulting precipitation pattern can depend critically on the wind speed and direction, as well as the terrain itself, the topographical precipitation processes often determine not only the climatic rainfall patterns of a region but also the interannual variability of this distribution.
- barrier flow;
- lee vortices;
- lee waves;
- monsoon circulations;
- rainfall enhancement;
- sea breeze;
- triggered convection