Ocean Science www.ocean-sci.net 1812-0784 1812-0792 5 3 2009 10.5194/os-5-313-2009 http://www.ocean-sci.net/5/313/2009/ http://www.ocean-sci.net/5/313/2009/os-5-313-2009.html http://www.ocean-sci.net/5/313/2009/os-5-313-2009.pdf 313 327 2009-08-20 Regional impacts of ocean color on tropical Pacific variability W. Anderson whit.anderson@noaa.gov A. Gnanadesikan A. Wittenberg NOAA Geophysical Fluid Dynamics Laboratory, Princeton NJ, USA The role of the penetration length scale of shortwave radiation into the surface ocean and its impact on tropical Pacific variability is investigated with a fully coupled ocean, atmosphere, land and ice model. Previous work has shown that removal of all ocean color results in a system that tends strongly towards an El Niño state. Results from a suite of surface chlorophyll perturbation experiments show that the mean state and variability of the tropical Pacific is highly sensitive to the concentration and distribution of ocean chlorophyll. 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