Greenpeace conducted an extensive study of ocean sequestration of CO2 and found that it might violate international law on waste dumping, do nothing to curb reckless use of hydrocarbon fuels, and potentially cause harm to ecosystems and to shipping.
Greenpeace: "The safety aspects of long term containment in this way also need to be addressed.
Rapid releases of carbon dioxide of volcanic origin have been reported. For example, a release from the crater lake Lake Nyos in Cameroon in 1986 killed more than 1500 people, and livestock was killed up to 14 km from the site (Hanisch, 1998). Even a slow seep of the gas from an aquifer could have serious implications for marine ecology, if not directly for terrestrial systems. If such a seep occurred at the sea-bed, it could cause widespread changes in benthic and water column ecology. Moreover,
to date, none of the proposals has addressed the potential ecological role of these deep formations or indeed described any of the associated ecosystems."
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