Extended Abstract (160K)P2.14
The global increase in blocking occurrences
Anthony R. Lupo, University of Missouri - Columbia, Columbia, MO; and J. V. Clark, K. Puricelli, and A. S. Kelly
Earlier work on the climatological frequency of blocking suggested that in a warmer climate, Northern Hemisphere blocking occurrences would increase, but they would become longer lived and less intense. Additionally, a recent increase in blocking frequency has been found for the Southern Hemisphere, even though other charactersitics, such as duration, and intensity are relatively unchanged. An investigation of recent increases in northern Hemispheric blocking are investigated here and shown to be consistent with earlier model studies. The data set used here was the National Center for Environmental Prediction (NCEP) and National Center for Atmospheric Research (NCAR) gridded re-analyses. The blocking criterion of Lupo and Smith (1995)was used here, and this can be summarized as a combination of a subjective criterion and objective criteria. Initial results show that both hemispehres have witnessed increases in blocking events. In the southern hemisphere, the increases have occurred throughout the year, while in the northern hemisphere, the summer season has witnessed the largest increases.
Poster Session 2, General Climate Studies: Poster Session
Monday, 21 January 2008, 2:30 PM-4:00 PM, Exhibit Hall B
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