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Radar Observations of the Formation and Evolution of Bow Echoes

出版	Brian Preiss, 2006
URL	http://books.google.com.hk/books?id=j7Ys0AEACAAJ&hl=&source=gbs_api

註釋Bow echoes are named for their bow shaped radar echo, and generally have damaging winds associated with them. The formation and evolution of 52 bow echo events, occurring in 2003 in the Northern Plains and Upper Mississippi Valley, were examined, using radar reflectivity data, for the initial mode as well as the type and the longevity of the bow echo. It was found that 47% of bow echoes evolved from weakly organized cells, 25% from organized cell groups, 24% from squall lines, and 4% from supercells. The most common bow echo evolution was from weakly organized cells to classic bow echoes, 25% of the total cases. It was also found that the longest lived bow echoes in this study evolved from weakly organized cells. Bow echoes that evolved from weakly organized cells had an average longevity of 390 minutes as compared with 252 minutes for squall lines, 191 minutes for organized cell groups, and 40 minutes for supercells.