ScienceDaily: By comparing reconstructions of atmospheric carbon dioxide (CO2) concentrations and sea level over the past 40 million years, researchers based at the National Oceanography Centre, Southampton have found that greenhouse gas concentrations similar to the present (almost 400 parts per million) were systematically associated with sea levels at least nine metres above current levels.
The study determined the 'natural equilibrium' sea level for CO2 concentrations ranging between ice-age values of 180...