This study investigated how Mediterranean cyclones impact chlorophyll-a dynamics. Using reanalysis data, ARGO floats, and satellite imagery, we found that slow-moving cyclones significantly uplift the deep chlorophyll maximum. Upwelling and air-sea heat exchange were key mechanisms driving this uplift, enhancing nutrient availability and primary productivity. These findings highlight the strong influence of cyclone intensity and movement on biogeochemical processes in the Mediterranean Sea.