A new study by internationally-recognized climate experts Stefan Rahmstorf and Michael Mann shows that human-caused melting of polar ice has slowed down currents in the Atlantic Ocean, particularly since 1970.

The researchers say one result of the slowdown is sea-level rise in cities like New York and Boston, and temperature changes on both sides of the Atlantic.

Mann, who is a professor and the director of the Earth System Science Center at Penn State University, tells  Here & Now’s Jeremy Hobson that the melting fresh water from polar ice could shut down the Gulf Stream much earlier than current climate models predict.

Current climate models project that the Gulf Stream could shut down by the end of the century. However, Mann says his projections suggest it could happen decades from now.

• Nature Climate Change: Exceptional twentieth-century slowdown in Atlantic Ocean overturning circulation

Guest

• Michael Mann, professor and director of the Earth System Science Center at Penn State University, and author of “The Hockey Stick and the Climate Wars: Dispatches From the Front Lines.” He tweets @MichaelEMann.

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