Methods of sequestering carbon dioxide (CO2) are provided. Aspects of the methods include contacting a CO2 containing gaseous stream with an aqueous medium under conditions sufficient to produce a bicarbonate rich product. The resultant bicarbonate rich product (or a component thereof) is then combined with a cation source under conditions sufficient to produce a solid carbonate composition and product CO2 gas, followed by injection of the product CO2 gas into a subsurface geological location to sequester CO2. Also provided are systems configured for carrying out the methods.