Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Climate change

Carbon drop in snail shell shock

Free-swimming snails show shell damage in water conditions that are likely to become more prevalent as the climate warms. By 2050, the top 200 metres of the Southern Ocean are likely to become under-saturated in a form of calcium carbonate called aragonite — a component of many shells. If aragonite structures are placed in waters in which the saturation state is less than one, they gradually dissolve.


Geraint Tarling of the British Antarctic Survey in Cambridge, UK, and his team analysed the shells of Limacina helicina antarctica pteropods (pictured) captured from the top 200 metres in an upwelling region of the Southern Ocean in 2008. Their shells were thinner and more porous than those captured elsewhere. In the laboratory, eight days of immersion in waters with a saturation state of between 0.94 and 1.12 produced similar levels of damage. Aragonite-shelled animals, important to food and carbon cycles, may decline sooner than expected in the Southern Ocean, the authors say.

Nature Geosci. (2012)

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Carbon drop in snail shell shock. Nature 491, 640 (2012).

Download citation


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing