In­flu­ence of car­bon di­ox­ide leak­age on the seabed


Storing carbon dioxide (CO2) deep below the seabed is one way to counteract the increasing concentration of CO2 in the atmosphere. But what happens if such storage sites begin to leak and CO2 escapes through the seafloor? Answers to this question have now been provided by a study dealing with the effects of CO2 emissions on the inhabitants of sandy seabed areas.

Day-in, day-out, we re­lease nearly 100 mil­lion tons of car­bon di­ox­ide (CO2) into the at­mo­sphere. One pos­sible meas­ure against stead­ily in­creas­ing green­house gases is known as CCS (car­bon cap­ture and stor­age): Here, the car­bon di­ox­ide is cap­tured, prefer­ably dir­ectly at the power plant, and sub­sequently stored deep in the ground or be­neath the seabed. However, this method poses the risk of reser­voirs leak­ing and al­low­ing car­bon di­ox­ide to es­cape from the ground into the en­vir­on­ment. The European research project ECO2, co­ordin­ated at GEO­MAR Helm­holtz Centre for Ocean Re­search Kiel, ad­dresses the ques­tion of how mar­ine eco­sys­tems re­act to such CO2-leaks. The field study of an in­ter­na­tional group of re­search­ers headed by Massimili­ano Mol­ari from the Max Planck In­sti­tute for Mar­ine Mi­cro­bi­o­logy in Bre­men and Katja Guilini from the Uni­versity of Ghent in Bel­gium, now pub­lished in Science Advances, re­veals how leak­ing CO2 af­fects the seabed hab­itat and its in­hab­it­ants.

For their study, the re­search­ers vis­ited nat­ural leaks of CO2 in the sandy seabed off the coast of Si­cily. They com­pared the local eco­sys­tem with loc­a­tions without CO2-vent­ing. In ad­di­tion, they ex­changed sand between sites with and without CO2-vent­ing in or­der to study how the bot­tom-dwell­ers re­spond and if they can ad­apt. Their con­clu­sion: In­creased CO2 levels drastic­ally al­ter the eco­sys­tem.

Continue reading at Max Planck Institute for Marine Microbiology

Image via C. Lott, HYDRA