While it is still (currently, at the beginning of October) a relatively quiet hurricane season in the Atlantic basin, tropical cyclones and typhoons have been very active in the western Pacific, perhaps augmented by the El Niño conditions.
In early August, Typhoon Morakot dropped heavy rainfall in Taiwan (Fig. 1), causing heavy floods and landslides. Heavy property damage and many human casualties were reported. More recently, Typhoon Ketsana passed over the Philippines, resulting in record breaking floods in the capital city Manila.
Figure 1. Accumulated rainfall during the passage of Typhoon Morakot over Taiwan, August 7-8, 2009. (Source: TOVAS —
http://disc2.nascom.nasa.gov/Giovanni/tovas/realtime.3B42RT_daily.shtml)
Currently, there are two active super typhoons (Fig. 2), Parma and Melor, near the Philippines. Super typhoons are defined as typhoons that reach maximum sustained 1-minute surface winds of at least 65 m/s (130 kt, 150 mph). A super typhoon is the equivalent of a strong Saffir-Simpson category 4 or category 5 hurricane in the Atlantic basin, according to the U.S. Joint Typhoon Warning Center. Parma was classified in the super typhoon category on October 1, but had weakened to a tropical storm by October 5. Melor was a massive circular storm on October 5, with a track headed toward Japan.
Figure 2. Animation of super typhoons Parma (western storm over the northern Phillipines) and Melor (eastern storm approaching the northern Marianas) on October 3, 2009. (Source: Hurricane Data Analysis Tool — http://disc.sci.gsfc.nasa.gov/hurricane/data-holdings/trmm_quikscat_analysis.shtml)
NASA Earth Observatory has additional imagery of both super typhoons, including a QuikSCAT wind vector image of Parma:
Typhoon Parma
Typhoon Melor
Atmos Composition
