Paper short abstract:

Attempting to repair ecosystems or maintain planetary inhabitability in the face of climate crises, the ocean's material capacity of absorbing CO2 is mobilised as hope-giving matter of concern for being utilized as a carbon sink via technoscientific practices of cultivating and sinking macroalgae.

Paper long abstract:

Under the impression of the ongoing loss of livelihoods, extinction of species and destruction of entire ecosystems the longing for hope is strong. To that end, the ocean as a projective empty and wide space provides a canvas and is being mobilised for various – at times speculative – technoscientific attempts to enabling livable futures.

My approach focusses less on the ocean as providing resources, but on (imaginations of) its capacity of reducing the harmful greenhouse gas carbon dioxide. These capacities are tried to be fostered by enhanced cultivation of macroalgae to absorb carbon dioxide from the surrounding water via photosynthesis and to finally sequestering carbon dioxide by sinking biomass in the deep sea. Herewith comes the implicit hope and explicit goal of healing damaged ecosystems by reducing atmospheric carbon dioxide through so called “negative emission technologies”. A side effect links to economic processes of carbon accounting and trading that does play a crucial role in oceanic future making.

This is a wonderful example of how materialities like the seawater, lifeforms such as algae, solar radiation, and chemical substances such as carbon dioxide are being (re)negotiated for enabling hopeful oceanic and planetary futures. Especially at the intersection of technoscientific (knowledge) practices and ecological crises which are at play, oceanic future making can be investigated fruitfully.

E-mail address: graul@em.uni-frankfurt.de , Format: Traditional presentation.