Clams shells can be one of the most accurate weather records

2010/10/01 Elhuyar Zientzia Iturria: Elhuyar aldizkaria

• Zoologia
• Klima

The study of oxygen isotopes in clams shells allows obtaining one of the most accurate climatic records. Most paleoclimatic measurements only provide annual temperature averages. However, clams constantly grow and oxygen isotope levels present in their shells vary depending on the temperature of the waters in which they live. The colder the water, the greater the proportion of 18 isotopes of oxygen. Therefore, registration through clams shells is much more accurate than the annual average. Temperatures can be analyzed at a resolution of less than a week and with the large clams you can obtain daily information.

To reach this conclusion, a group of researchers from the University of Saskatchewan (Canada) has studied the shells of about 26 old clams from the sediment cores in Iceland Bay. Clams normally live between 2 and 9 years, so the proportion of isotopes in each shell also offers a "window" or data on the environmental conditions of the places where they have developed. Technically, they measure water temperature records in shells of molluscs and not air. But both are directly related, especially on the coasts.

This study has already obtained a continuous or continuous record of the samples collected by the researchers in the last 400 years. In addition, the authors of the study claim that it can offer details of 11,000 years ago.