CO 2 clathrate hydrate is a crystalline material composed of water cages around a CO 2 molecule. CO 2 gas hydrates are naturally occurring on Earth and are a likely phase on Mars as well as other cold planetary bodies. CO 2 hydrates have minor effects on terrestrial atmospheric composition, but may be a major reservoir for greenhouse gases on Mars. In this study, CO 2 hydrate formation and dissociation rates were measured experimentally on ultrapure and CO 2 infused water ice (ice containing previously trapped CO 2 gas bubbles). Overall, increasing pressure and temperature increased CO 2 consumption rates, indicating enhanced hydrate formation rates. CO 2 consumption and release rates both increased significantly in infused ice experiments as did the overall amount of CO 2 consumed. CO 2 bubbles formed during freezing of the infused ice likely provided more surface area for hydrate nucleation, increasing the rate of formation. Higher dissociation rates in infused ice experiments compared to ultrapure ice may be due to the higher concentration of hydrate originally formed in the bubble-filled samples. These results suggest that CO 2 hydrate formation in natural, gas-rich ice occurs significantly faster than previously assumed. In addition, formation rates would be maximized and dissociation rates minimized at Mars equatorial conditions, perhaps leading to long-term storage of atmospheric CO 2 in localized clathrate reservoirs.