Meteorological Applications

Clear air turbulence over South Africa

M P de Villiers  a1 and van Heerden  a2
a1 South African Weather Bureau, Private Bag X97, Pretoria, South Africa
a2 University of Pretoria, Department of Civil Engineering, Pretoria, South Africa

Article author query
van heerden j   [Google Scholar] 


Clear air turbulence (CAT) at high altitude remains a hazard to aviation which can result in passenger injury and aircraft damage. Two limited surveys of CAT events over South Africa, 1993-1995 (inclusive) and 1998, are used to illustrate the most likely synoptic conditions under which CAT can be expected. A case study of CAT associated with an upper-air trough and a mountain wave is presented. The study also evaluates the effectiveness of the Ellrod Turbulence Index (ETI) derived from model data provided by the UK Met. Office. A forecast of ETI derived from the Global Spectral Model of the United States National Center for Environmental Prediction (NCEP) is also reviewed.