As human-caused greenhouse gas emissions continue to rise beyond limits for what our species has experienced, researchers are looking to a mystery in the past to answer questions about what may lay ahead.
This work, published today in Nature Communications by an international team of scientists, is part of a project called the 2nd Pliocene Model Intercomparison Project, or PlioMIP2.
The team focused on the climate of the Pliocene, over 3 million years ago, the last time Earth has seen concentrations of over 400 PPM CO2 in the atmosphere, similar to today’s concentrations. The Pliocene prompts a long-standing question, says UConn Department of Geosciences researcher and lead author Ran Feng: despite the similarity to the present-day, why were dry areas like the Sahel in Africa and Northern China much wetter and greener in the Pliocene than they are today?
The Pliocene was warmer than present-day conditions by 2 to 3°C, and everything we know about the physics of the climate system suggests the Pliocene should have been drier in the subtropics, says co-author Tripti Bhattacharya, Thonis Family Professor of Earth and Environmental Sciences at Syracuse University.
Read more at: University of Connecticut
A map showing the biome and ice sheet distribution of the mid-Pliocene. (Photo Credit: Ran Feng)