Icebergs in Florida? A discovery in the Atlantic may unravel our explanation of climate change

Scarring of the ocean floor off the Atlantic coast gives indication that enormous icebergs once reached as far south as Florida.

by John Tyburski

Copyright © Daily Digest News, KPR Media, LLC. All rights reserved.

First published at Daily Digest News on October 14, 2014

How about something really cool? A new report documents evidence for ancient gigantic icebergs off the Atlantic coast, having once traveled as far south as Florida. The ocean floor off the coasts of South Carolina, Georgia, and Florida is scarred with V-shaped trenches cut by huge icebergs brought down thousands of years ago by staggering arctic flooding from the north.

Approximately 20,000 years ago, giant fresh water lakes covered what is now Canada, and their frigid waters were held in by ice dams. Lakes the size of the Caspian Sea sometimes broke through their dams and flooded southward into the Atlantic ocean, carrying with them fleets of jagged icebergs. The trenches cut along the Atlantic coast suggests the icebergs came as far south as Florida.

This new discovery, published this week in the journal Nature Geoscience, will likely change thw ay scientists understand global warming, ice cap melting, and ocean currents.

“The mechanisms of climate change and ocean currents are more complex than we previously thought,” study author Jenna Hill, a marine scientist at Coastal Carolina University, said in a statement. “It helps us understand how future ice sheet melt from Greenland may affect global climate.”

Co-author Alan Condron said that the ocean floor scours indicate that the icebergs may have been up to 1,000 feet thick, the size of those one can only find off the coast of Greenland today.

“Previous research would have suggested the meltwater would have gone much further north, so people weren’t expecting the subtropics to become fresher,” said Condron, an oceanographer at the University of Massachusetts, Amherst. “This actually has enormous implications for that model and for what triggers climate change.”

“This new research shows that much of the meltwater from the Greenland ice sheet may be redistributed by narrow coastal currents and circulate through subtropical regions prior to reaching the subpolar ocean,” Condron added.