Washington, June 18 (IANS) Scientists have found the apparent role of carbon dioxide in the intensification of the Ice Ages and corresponding temperature changes in the tropical oceans.
The research, led by a team of Brown University, has established that the climate in the tropics over the last 2.7 million years changed with the cyclical spread and retreat of ice sheets thousands of miles away in the Northern Hemisphere.
The research team, including scientists from Luther College in Iowa, Lafayette College in Pennsylvania and the University of Hong Kong, analysed cores taken from the seabed at four locations in the tropical oceans: the Arabian Sea, the South China Sea, the eastern Pacific and the equatorial Atlantic Ocean.
These showed that climate patterns in the tropics have mirrored Ice Age cycles for the last 2.7 million years and that carbon dioxide has played a leading role in determining global climate patterns.
Researchers zeroed in on tropical ocean surface temperatures because these vast bodies, which make up roughly half of the world’s oceans, orchestrate the amount of water in the air and rainfall patterns worldwide, as well as the concentration of water vapour, said a Brown University release.
‘We think we have the simplest explanation for the link between the Ice Ages and the tropics over that time and the apparent role of carbon dioxide in the intensification of Ice Ages and corresponding changes in the tropics,’ said Timothy Herbert of Brown University.