ANGEO Annales Geophysicae ANGEO 1432-0576 Copernicus GmbH Göttingen, Germany 10.5194/angeo-28-141-2010 Wind profiler observations on orographic effects of typhoon wind structure modification over Taiwan (120.38° E, 22.6° N) Pan C. J. 1 Krishna Reddy K. 2 Lai H. C. 3 Yang S. S. 1 Wong C. J. 4 Institute of Space Science, National Central University, Taiwan Department of Physics, Yogi Vemana University, Kadapa, India Dept. of Eng. & Manag. of Advanced Tech., Chang Jung Christian University, Taiwan School of Physics, Universiti Sains Malaysia, Malaysia 18 01 2010 28 1 141 147 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.ann-geophys.net/28/141/2010/angeo-28-141-2010.html The full text article is available as a PDF file from http://www.ann-geophys.net/28/141/2010/angeo-28-141-2010.pdf

The interaction of the storm circulation with the Central Mountain Range (CMR) of Taiwan is studied with a wind profiler located at the leeside during the invasions of two (Kaemi (200605) and Bopha (200609)) typhoons. The moderate typhoon Kaemi upgraded from a tropical depression on 21 July 2006. It then was made landfall at 15:45 UTC on 24 July 2006 near Cheng-Kung. The weak typhoon Bopha formed at about 12:00 UTC on 5 August 2006 and also landed near Cheng-Kung at around 19:20 UTC on 8 August. A new finding from both typhoons is the vortex splitting into upper and lower parts with the two typhoons that have passed the observation site nearly. For the typhoon Kaemi, demarcation height of the upper-level vortex and lower level is at 2.8 km and passed the site about 3 h earlier than the low-level one. For the typhoon Bopha, the center of the lower-level vortex at 3.5 km locates to the north of the upper-level one at 5.2 km. The re-organization of the split vortexes is found in typhoon Kaemi but not for typhoon Bopha.

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