Jurassic records warn of risk to marine life from global warming

The risk posed by global warming and rising ocean temperatures to the future health of the world’s marine ecosystem has been highlighted by scientists studying fossil records. Researchers at Plymouth University believe that findings from fieldwork along the North Yorkshire coast reveal strong parallels between the Early Jurassic era of 180 million years ago and current climate predictions over the next century. Through geology and palaeontology, they’ve shown how higher temperatures and lower oxygen levels caused drastic changes to marine communities, and that while the Jurassic seas eventually recovered from the effects of global warming, the marine ecosystems that returned were noticeably different from before. The results of the Natural Environment Research Council-funded project are revealed for the first time in this month’s PLOS ONE scientific journal. Richard Twitchett, from the University’s School of Geography, Earth and Environmental Sciences, and a member of its Marine Institute, said: “Our study of fossil marine ecosystems shows that if global warming is severe enough and lasts long enough it may cause the extinction of marine life, which irreversibly changes the composition of marine ecosystems. Twitchett, with Plymouth colleagues Silvia Danise and Marie-Emilie Clemence, undertook fieldwork between Whitby and Staithes, studying the different sedimentary rocks and the marine fossils they contained. This provided information about the environmental conditions on the sea floor at the time the rocks were laid down.