Comparison of the Energy Efficiency between Typhoon Bolaven and Typhoon Tembin in 2012, Korea

Both Typhoon Bolaven and Typhoon Tembin hit Korea severely in 2012. Typhoon Bolaven was regarded as the most powerful storm to strike the Korean Peninsula in nearly a decade, with wind gusts measured up to 186 km h-1. After forming as tropical depression on August 19, 2012, Bolaven was steadily intensified up to category 4 -equivalent typhoon. Then steady weakening continued as Bolaven approached to the Korean Peninsula and it eventually made landfall in North Korea late on August 28 before transitioning into an extratropical cyclone. Typhoon Tembin was a strong tropical cyclone which unusually made landfall Taiwan twice and made landfall over South Korea on August 30 before becoming extratropical storm. This typhoon was followed to the Fujiwhara effect after Typhoon Bolaven. It was a typhoon with the pressure of 975hPa and the maximum wind speed of 45m s-1 .

Although two typhoons passed in similar time in August, the type of damages on Korean peninsula were clearly different. Typhoon Bolaven had severe rainfall all over Korea including Jeju Island with more than 250 mm in 2 days. However, Typhoon Tembin moved northeasterly with wind speed of 45 km h-1 and brought more damages from strong wind.

In this study, the energy efficiencies were calculated and compared to see their inner structures to cause damages in Korean peninsula. To compare each energy efficiency between two typhoons, dual Doppler analyses by S-band radars were used to retrieve the wind fields. Also, the sounding temperature data were used to investigate the different atmospheric structures between the convective regions associated with the TC center, the principal rain band, and the region between them.

These results will be presented in detail at the conference poster session.