Open AccessProperties of strong off‐shore Borneo vortices: a composite analysis of flow pattern and composition as captured by ERA‐Interim
Author(s) -
Braesicke Peter,
See Hai Ooi,
Abu Samah Azizan
Publication year - 2012
Publication title -
atmospheric science letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.951
H-Index - 45
ISSN - 1530-261X
DOI - 10.1002/asl.372
Subject(s) - vortex , shore , relative humidity , tropopause , atmospheric sciences , climatology , environmental science , latitude , meteorology , flow (mathematics) , vorticity , humidity , geology , geography , oceanography , physics , mechanics , troposphere , geodesy
The Borneo vortex (BV) is an important source of extreme weather for Malaysia. We describe climatological properties of strong off‐shore BVs using a potential vorticity (PV) threshold analysis of ERA‐Interim data. The composite BV at the location of most likely high PV occurrence has a warm core with enhanced specific humidity between 800 and 200 hPa, and a dry layer above. Two effects contribute to this structure: Air is vertically transported upwards in the BV whilst precipitating and the large scale flow in which the BV is embedded advect dry, ozone‐rich air from the equatorial tropical tropopause layer towards higher latitudes. Copyright © 2012 Royal Meteorological Society