A word in your shell like...

Finding a seashell is one of the many pleasures of a summer holiday on the coast - but many people will not be aware that they have found a unique record of the climate.

Not just a holiday souvenir – shells can climactic record keepers

For one German scientist however these hard calcium shells provide a profound insight into the history of our earth and especially into the climate of the past. Professor Bernd Schöne - a palaeontologist from Mainz University - thinks that by examining shells he can reconstruct the climatic history of the past 500 years.

“We can demonstrate, for example, that the North Sea has become one degree warmer over the past hundred years, probably an effect attributable to humans,” said Schöne.

Molluskan sclerochronology – as the technique is called - is still in its infancy. However, Schöne thinks that before long we shall know what climatic fluctuations took place in the North Sea and the North Atlantic in past millennia and what exactly has changed since then.

Shells are a unique climate archive as they have clearly delineated growth patterns that show changing nutritional conditions, temperature fluctuations and environmental pollution. And it isn’t just local information that can be gleaned from their study - shells are found all over the world, in the polar regions and at the equator, on land and in the ocean, in deeper waters and on ocean shelves, and in rivers, streams and lakes.

“Shells are simply everywhere and, depending on their location, they provide us with important information about climatic developments. They serve as records of volcanic eruptions in Iceland or the occurrence of a hurricane in Florida; they can, for example, even tell us whether the early Indian tribes on the western coast of Canada collected mollusks during full moon, crescent moon or new moon periods,” said Schöne.