Atmospheric Chemistry and Physics www.atmos-chem-phys.net 1680-7316 1680-7324 9 4 2009 10.5194/acp-9-1407-2009 http://www.atmos-chem-phys.net/9/1407/2009/ http://www.atmos-chem-phys.net/9/1407/2009/acp-9-1407-2009.html http://www.atmos-chem-phys.net/9/1407/2009/acp-9-1407-2009.pdf 1407 1417 2009-02-20 Intensification of tropical cyclones in the GFS model J. C. Marín juliocma@atmosfera.unam.mx D. J. Raymond G. B. Raga Centro de Ciencias de la Atmósfera, UNAM, Mexico City, Mexico Physics Department, New Mexico Tech., Socorro, USA Special forecasts from the Global Forecast System (GFS) model were used in this study to evaluate how the intensification process in a tropical cyclone is represented in this model. Several tropical cyclones that developed in 2005 were analyzed in terms of the storm-scale circulation rather than more traditional measures such as maximum wind or minimum central pressure. 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