This research is supported by NASA Grant NNX06AC08G and Dr. Ramesh Kakar of NASA Headquarters. Special thanks to Dr. Chuntao Liu for obtaining the GDAS analyses and 3B42 data and for his help in the development of the figures, and to Ken Knapp for providing the ISSCP B1 North Atlantic basin dataset. Numerous conversations with Dr. Brandon Kerns were helpful in developing this manuscript. The authors wish to acknowledge Dr. Sharon Nicholson and two anonymous reviewers for comments that helped improve this manuscript. This study began as a class project and participating students of the University of Utah include Byoung-Cheol Kim, Xuanli Li, Brian Olsen, Christy Wall, Greg West, and Weixin Xu.
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