A new study of fossil fuel shows that the warming of the polar oceans during the Eocene period was much greater than the scientists have previously estimated. Eocene is a greenhouse period that helps in determining the Earth's future climate.
Researchers studied the chemical composition of fossilized foraminifera which are tiny single-celled animals that lived in shallow tropical waters. They were able to precisely figure out tropical sea surface temperatures and seawater chemistry during the Eocene Epoch period which lasted from 56 million years ago to 34 million years ago. Researched were able to calibrate the estimates from previous studies that determined polar conditions to prove that the tropical oceans did warm up in the Eocene period but not as much as polar oceans. The disparity between the two values might further raise the possibility that the estimates of future polar warming might be too low. The fact that the Polar Regions are warming at a much higher rate than the tropics is something that needs to be considered in various climate models. When the Eocene period started, the concentration of carbon dioxide in the atmosphere was 560 parts per million, which is twice of pre-industrial levels. The global average temperature was more than 8 degrees Celsius warmer than today. This makes the Eocene period quite a good period to test the understanding of our climate system. The difference between polar and tropical temperatures during the Eocene period was around 20 degrees Celsius while today it is around 28 degrees Celsius.