Most of the concerns about climate change have focused on the amount of greenhouse gases that have been released into the atmosphere. But in a new study published in Science, a group of Rutgers researchers have found that circulation of the ocean plays an equally important role in regulating Earth’s climate… The ocean conveyor system, Rutgers scientists believe, changed at the same time as a major expansion in the volume of the glaciers in the northern hemisphere as well as a substantial fall in sea levels. It was the Antarctic ice, they argue, that cut off heat exchange at the ocean’s surface and forced it into deep water. They believe this caused global climate change at that time, not carbon dioxide in the atmosphere… “We argue that it was the establishment of the modern deep ocean circulation — the ocean conveyor — about 2.7 million years ago, and not a major change in carbon dioxide concentration in the atmosphere that triggered an expansion of the ice sheets in the northern hemisphere,” says Stella Woodard, lead author and a post-doctoral researcher in the Department of Marine and Coastal Sciences. Their findings, based on ocean sediment core samples between 2.5 million and 3.3 million years old, provide scientists with a deeper understanding of the mechanisms of climate change today.