Wind Shear 4 : An extremely rapid change of either wind speed or direction or both, in any direction, conventionally expressed as vertical wind or horizontal wind shear
Ilan Kelman (ed.), Vulnerability and Resilience Definitions and References, Version 2, 2007. http://www.islandvulnerability.org/docs/vulnres.pd f, (Vulnr and Resilience - Brit) {524}